You searched for +publisher:"Dalhousie University" +contributor:("Hal Whitehead").
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Dalhousie University
1.
MacIsaac, Kevin Gregory.
The Larger Pelagic Crustacea of the Gully Submarine
Canyon.
Degree: MS, Department of Biology, 2011, Dalhousie University
URL: http://hdl.handle.net/10222/14245 
► The larger pelagic crustacean fauna of the Gully submarine canyon is described for the first time, based on three annual summer surveys. The larger Crustacea…
(more)
▼ The larger pelagic crustacean fauna of the Gully
submarine canyon is described for the first time, based on three
annual summer surveys. The larger Crustacea are a significant part
of the Gully fauna, and are dominated by cold temperate species, in
particular the northern krill Meganyctiphanes norvegica and the
decapod Sergestes arcticus. In all, at least 69 species were
collected from the surface to bathypelagic depths, with seventeen
being new Canadian records. With the exception of M. norvegica,
inter-annual variation in the dominant species was minor. The
species assemblage varied primarily with depth surveyed and diel
cycle, and not year. Comparing the larger pelagic crustaceans in
the Gully and over the adjacent continental slope showed that
overall species number, biomass, and abundance were all greater in
the canyon, the biomass of S. arcticus particularly showing a
positive “Gully effect”.
Advisors/Committee Members: Tracey Sutton (external-examiner), Hal Whitehead (graduate-coordinator), Ian McLaren, Sandra Walde, Hal Whitehead (thesis-reader), Ellen Kenchington (thesis-supervisor), Not Applicable (ethics-approval), Not Applicable (manuscripts), Not Applicable (copyright-release).
Subjects/Keywords: Pelagic Crustacea; micronekton; The Gully; submarine
canyon; vertical distribution; species assemblage; annotated
species list; new species records; rare species; Meganyctiphanes
norvegica; Sergestes arcticus
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APA (6th Edition):
MacIsaac, K. G. (2011). The Larger Pelagic Crustacea of the Gully Submarine
Canyon. (Masters Thesis). Dalhousie University. Retrieved from http://hdl.handle.net/10222/14245
Chicago Manual of Style (16th Edition):
MacIsaac, Kevin Gregory. “The Larger Pelagic Crustacea of the Gully Submarine
Canyon.” 2011. Masters Thesis, Dalhousie University. Accessed April 12, 2021.
http://hdl.handle.net/10222/14245.
MLA Handbook (7th Edition):
MacIsaac, Kevin Gregory. “The Larger Pelagic Crustacea of the Gully Submarine
Canyon.” 2011. Web. 12 Apr 2021.
Vancouver:
MacIsaac KG. The Larger Pelagic Crustacea of the Gully Submarine
Canyon. [Internet] [Masters thesis]. Dalhousie University; 2011. [cited 2021 Apr 12].
Available from: http://hdl.handle.net/10222/14245.
Council of Science Editors:
MacIsaac KG. The Larger Pelagic Crustacea of the Gully Submarine
Canyon. [Masters Thesis]. Dalhousie University; 2011. Available from: http://hdl.handle.net/10222/14245
Dalhousie University
2.
O'Brien, Kristin.
POPULATION STATUS AND SOCIAL STRUCTURE OF NORTHERN
BOTTLENOSE WHALES (HYPEROODON AMPULLATUS) ON THE SCOTIAN
SHELF.
Degree: MS, Department of Biology, 2013, Dalhousie University
URL: http://hdl.handle.net/10222/35342
► I examined the dynamics of an endangered population of northern bottlenose whales over a 23-year period during which its prime habitat, the Gully canyon, was…
(more)
▼ I examined the dynamics of an endangered population of
northern bottlenose whales over a 23-year period during which its
prime habitat, the Gully canyon, was made a Marine Protected Area
(MPA). Using mark-recapture techniques on photo-identifications I
estimate a current population of 116 animals (95% CI=101-130). The
population size and sex-ratio have remained stable since before the
MPA designation suggesting this population is persisting. I used
photo-identifications and high definition videography to examine
the social organization of northern bottlenose whales, including
behavioural synchrony. Relationships are highly variable; most
associations are short-lived, but there are also long-term
preferred associations lasting from several years (female/immature
dyads) to over a decade (mature male dyads). I found little, if
any, division of the social community. Synchronized breathing is
common, precise, and appears to vary with behaivoural context.
Although speculative, synchronized breathing might play a role the
maintenance of general social relationships within this
population.
Advisors/Committee Members: n/a (external-examiner), Hal Whitehead (graduate-coordinator), Marty Leonard (thesis-reader), Don Bowen (thesis-reader), Hal Whitehead (thesis-supervisor), Not Applicable (ethics-approval), Yes (manuscripts), Yes (copyright-release).
Subjects/Keywords: Cetacean; Beaked whale; Marine Protected Area; Photo-identification
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APA (6th Edition):
O'Brien, K. (2013). POPULATION STATUS AND SOCIAL STRUCTURE OF NORTHERN
BOTTLENOSE WHALES (HYPEROODON AMPULLATUS) ON THE SCOTIAN
SHELF. (Masters Thesis). Dalhousie University. Retrieved from http://hdl.handle.net/10222/35342
Chicago Manual of Style (16th Edition):
O'Brien, Kristin. “POPULATION STATUS AND SOCIAL STRUCTURE OF NORTHERN
BOTTLENOSE WHALES (HYPEROODON AMPULLATUS) ON THE SCOTIAN
SHELF.” 2013. Masters Thesis, Dalhousie University. Accessed April 12, 2021.
http://hdl.handle.net/10222/35342.
MLA Handbook (7th Edition):
O'Brien, Kristin. “POPULATION STATUS AND SOCIAL STRUCTURE OF NORTHERN
BOTTLENOSE WHALES (HYPEROODON AMPULLATUS) ON THE SCOTIAN
SHELF.” 2013. Web. 12 Apr 2021.
Vancouver:
O'Brien K. POPULATION STATUS AND SOCIAL STRUCTURE OF NORTHERN
BOTTLENOSE WHALES (HYPEROODON AMPULLATUS) ON THE SCOTIAN
SHELF. [Internet] [Masters thesis]. Dalhousie University; 2013. [cited 2021 Apr 12].
Available from: http://hdl.handle.net/10222/35342.
Council of Science Editors:
O'Brien K. POPULATION STATUS AND SOCIAL STRUCTURE OF NORTHERN
BOTTLENOSE WHALES (HYPEROODON AMPULLATUS) ON THE SCOTIAN
SHELF. [Masters Thesis]. Dalhousie University; 2013. Available from: http://hdl.handle.net/10222/35342
Dalhousie University
3.
Milligan, Marina.
Fine-scale distribution, habitat use, and movements of sperm
whales.
Degree: MS, Department of Biology, 2013, Dalhousie University
URL: http://hdl.handle.net/10222/36305
► Sperm whales (Physeter macrocephalus) are nomadic species typically studied across broad (>100km) spatial scales. In this study, I model fine-scale (or submesocale) habitat preferences, determine…
(more)
▼ Sperm whales (Physeter macrocephalus) are nomadic
species typically studied across broad (>100km) spatial scales.
In this study, I model fine-scale (or submesocale) habitat
preferences, determine how organization into distinctive units of
associating female and juveniles influences habitat use, and
describe how movements change across the 24-hour cycle. This study
concerns a well-studied population of sperm whales off Dominica in
the Eastern Caribbean. Statistical models suggest that overall
habitat use is rather homogenous, and social behaviour is best
predicted by the presence of mature males. Variation among social
units in the amount of time spent, and space occupied, within the
study area indicates habitat preferences at the level of the social
unit. Finally, movements are influenced by the diurnal cycle, as
whales tend to move from inshore to offshore at dusk. This study
betters our understanding of sperm whale habitat decisions over
fine-scales, and has implication for conservation and management
strategies.
Advisors/Committee Members: n/a (external-examiner), Hal Whitehead (graduate-coordinator), Ian Jonsen (thesis-reader), Marlon Lewis (thesis-reader), Hal Whitehead (thesis-supervisor), Not Applicable (ethics-approval), Not Applicable (manuscripts), Not Applicable (copyright-release).
Subjects/Keywords: sperm whale; Physeter macrocepahlus; habitat; movement; nomad; generalized estimating equations; social unit; social behaviour; defecation rate; anthropogenic disturbance; diurnal cycle
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APA (6th Edition):
Milligan, M. (2013). Fine-scale distribution, habitat use, and movements of sperm
whales. (Masters Thesis). Dalhousie University. Retrieved from http://hdl.handle.net/10222/36305
Chicago Manual of Style (16th Edition):
Milligan, Marina. “Fine-scale distribution, habitat use, and movements of sperm
whales.” 2013. Masters Thesis, Dalhousie University. Accessed April 12, 2021.
http://hdl.handle.net/10222/36305.
MLA Handbook (7th Edition):
Milligan, Marina. “Fine-scale distribution, habitat use, and movements of sperm
whales.” 2013. Web. 12 Apr 2021.
Vancouver:
Milligan M. Fine-scale distribution, habitat use, and movements of sperm
whales. [Internet] [Masters thesis]. Dalhousie University; 2013. [cited 2021 Apr 12].
Available from: http://hdl.handle.net/10222/36305.
Council of Science Editors:
Milligan M. Fine-scale distribution, habitat use, and movements of sperm
whales. [Masters Thesis]. Dalhousie University; 2013. Available from: http://hdl.handle.net/10222/36305
Dalhousie University
4.
Keith, David.
FORECASTING FUTURES - THE EFFECT OF AGE, ABUNDANCE, AND
HARVESTING ON THE LONG-TERM SUSTAINABILITY OF MARINE FISHES.
Degree: PhD, Department of Biology, 2014, Dalhousie University
URL: http://hdl.handle.net/10222/53966
► In the first part of this thesis I attempt to address some of the concerns regarding the stock-recruitment relationship that have been voiced over the…
(more)
▼ In the first part of this thesis I attempt to address
some of the concerns regarding the stock-recruitment relationship
that have been voiced over the last 50 years. In chapter 2 I
revisit the shape of the stock-recruitment relationship at low
abundance. I show that at these low abundances an increase in
productivity is not ubiquitous. In many populations the dynamics
are essentially density independent after the populations decline
below 40% of maximum historic SSB, and in some species the
productivity actually starts to decline below this threshold. Given
the weakening of compensation in many populations, in chapter 3 I
examine how per capita harvest mortality changes with abundance.
The results show that in the majority of populations, per capita
mortality continues to increase with declines in abundance. In
Chapter 4, I attempt to address concerns that have been raised
about the effect of age structure on recruitment. Here, I break
down the relationship to determine whether there is an effect of
first time (virgin) or repeat spawners in terms of average size,
and the relative abundance of large and small fish. The results
suggest that these age-specific components of the spawning stock
contribute differentially to recruitment across a wide range of
species and populations. In Chapters 5 and 6 I change the focus and
use a technique widely used in terrestrial ecology to estimate both
the risk of collapse and the probability of persistence for
numerous populations of Atlantic cod (Gadus morhua) and Atlantic
herring (Clupea harengus). In chapter 5 the models indicate that
periods of unusually elevated recruitment are vital to the
persistence of all the populations analyzed. In Chapter 6, I look
specifically at the potential impact that different management
actions and environmental variability may have on population
recovery for an endangered Atlantic cod population in the Gulf of
St. Lawrence. Throughout this thesis, I attempt to address problems
in fisheries science from a more ecological perspective than that
traditionally used in fisheries science. More collaboration between
ecologist scientists and fisheries scientist will only help to
improve our understanding of population dynamics in both marine and
terrestrial ecosystems.
Advisors/Committee Members: Dr. Andrew Cooper (external-examiner), Dr. Hal Whitehead (graduate-coordinator), Dr. Nancy Shackell (thesis-reader), Dr. Hal Whitehead (thesis-reader), Dr. Jeff Hutchings (thesis-supervisor), Not Applicable (ethics-approval), Yes (manuscripts), Yes (copyright-release).
Subjects/Keywords: Fisheries; Biology; Ecology; Population viability analysis; Allee effect; recovery; harvesting
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APA (6th Edition):
Keith, D. (2014). FORECASTING FUTURES - THE EFFECT OF AGE, ABUNDANCE, AND
HARVESTING ON THE LONG-TERM SUSTAINABILITY OF MARINE FISHES. (Doctoral Dissertation). Dalhousie University. Retrieved from http://hdl.handle.net/10222/53966
Chicago Manual of Style (16th Edition):
Keith, David. “FORECASTING FUTURES - THE EFFECT OF AGE, ABUNDANCE, AND
HARVESTING ON THE LONG-TERM SUSTAINABILITY OF MARINE FISHES.” 2014. Doctoral Dissertation, Dalhousie University. Accessed April 12, 2021.
http://hdl.handle.net/10222/53966.
MLA Handbook (7th Edition):
Keith, David. “FORECASTING FUTURES - THE EFFECT OF AGE, ABUNDANCE, AND
HARVESTING ON THE LONG-TERM SUSTAINABILITY OF MARINE FISHES.” 2014. Web. 12 Apr 2021.
Vancouver:
Keith D. FORECASTING FUTURES - THE EFFECT OF AGE, ABUNDANCE, AND
HARVESTING ON THE LONG-TERM SUSTAINABILITY OF MARINE FISHES. [Internet] [Doctoral dissertation]. Dalhousie University; 2014. [cited 2021 Apr 12].
Available from: http://hdl.handle.net/10222/53966.
Council of Science Editors:
Keith D. FORECASTING FUTURES - THE EFFECT OF AGE, ABUNDANCE, AND
HARVESTING ON THE LONG-TERM SUSTAINABILITY OF MARINE FISHES. [Doctoral Dissertation]. Dalhousie University; 2014. Available from: http://hdl.handle.net/10222/53966
Dalhousie University
5.
Burns, Lynne.
Dynamics of autumn swarming and population structure of
little brown and northern Myotis bats (Myotis lucifugus and M.
septentrionalis).
Degree: PhD, Department of Biology, 2014, Dalhousie University
URL: http://hdl.handle.net/10222/53211
► As a fundamental unit in evolutionary ecology and the base unit for management, the population is of immense interest in understanding a species’ ecology. Individuals…
(more)
▼ As a fundamental unit in evolutionary ecology and the
base unit for management, the population is of immense interest in
understanding a species’ ecology. Individuals are the foundation of
populations where their diversity in behaviours can scale up to
variation in other traits that characterize population dynamics.
Understanding the variation of individuals in their behaviours and
traits within a population (i.e., their structure) is therefore of
great importance in characterizing populations. Bats are highly
vagile and gregarious animals that show variation among sex and age
classes in many stages of their annual cycle that are best
understood during the summer and winter seasons. In this thesis I
explored the dynamics in activity of two temperate bats, little
brown Myotis (M. lucifugus) and northern Myotis (M.
septentrionalis) during swarming in autumn to characterize aspects
of their population structures. To examine intersexual differences
in swarming activities bats were captured and tagged at multiple
swarming sites to characterize intersexual differences in the
frequency and extent of re-use of swarming sites. I explored the
associations among sex and age classes of each species to test
predictions of hypotheses on the functions of swarming of gene flow
and information transfer from mother bats to offspring. Lastly, I
characterized population genetic structure of M. lucifugus to study
the reproductive cohesion of bats - gene flow- among swarming
sites. Male bats were found to have higher swarming activity
compared to females which may reflect males spending more time
devoted to swarming to maximize mating opportunities. Predictable
age and sex class groups were found during swarming where
young-of-the-year were found to have the highest associations with
other bats and most preferentially with other young-of-the-year.
Adult male and female bats were most often captured alone, but when
males were captured they showed preference for grouping with other
males, including male M. lucifugus having preferred male associates
across nights. Genetic data for M. lucifugus were suggestive of
high gene flow and thus a high degree of reproductive connectivity
among swarming sites. Together these results provide information of
how variation among individuals contributes to population
structure.
Advisors/Committee Members: Dr. Gareth Jones (external-examiner), Dr. Hal Whitehead (graduate-coordinator), Dr. Marty Leonard (thesis-reader), Dr. Timothy Frasier (thesis-reader), Dr. Hugh Broders, Dr. Hal Whitehead (thesis-supervisor), Received (ethics-approval), Yes (manuscripts), Yes (copyright-release).
Subjects/Keywords: population biology
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APA ·
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APA (6th Edition):
Burns, L. (2014). Dynamics of autumn swarming and population structure of
little brown and northern Myotis bats (Myotis lucifugus and M.
septentrionalis). (Doctoral Dissertation). Dalhousie University. Retrieved from http://hdl.handle.net/10222/53211
Chicago Manual of Style (16th Edition):
Burns, Lynne. “Dynamics of autumn swarming and population structure of
little brown and northern Myotis bats (Myotis lucifugus and M.
septentrionalis).” 2014. Doctoral Dissertation, Dalhousie University. Accessed April 12, 2021.
http://hdl.handle.net/10222/53211.
MLA Handbook (7th Edition):
Burns, Lynne. “Dynamics of autumn swarming and population structure of
little brown and northern Myotis bats (Myotis lucifugus and M.
septentrionalis).” 2014. Web. 12 Apr 2021.
Vancouver:
Burns L. Dynamics of autumn swarming and population structure of
little brown and northern Myotis bats (Myotis lucifugus and M.
septentrionalis). [Internet] [Doctoral dissertation]. Dalhousie University; 2014. [cited 2021 Apr 12].
Available from: http://hdl.handle.net/10222/53211.
Council of Science Editors:
Burns L. Dynamics of autumn swarming and population structure of
little brown and northern Myotis bats (Myotis lucifugus and M.
septentrionalis). [Doctoral Dissertation]. Dalhousie University; 2014. Available from: http://hdl.handle.net/10222/53211
Dalhousie University
6.
Magera, Anna M.
Marine Mammal Population Recoveries and Critical
Factors.
Degree: MS, Department of Biology, 2011, Dalhousie University
URL: http://hdl.handle.net/10222/13330
► Of all the marine taxa, marine mammals seem to have benefited the most from a paradigm shift from exploitation to conservation. This thesis provides the…
(more)
▼ Of all the marine taxa, marine mammals seem to have
benefited the most from a paradigm shift from exploitation to
conservation. This thesis provides the first quantitative
assessment for marine mammals of (1) global, publicly available
population-level abundance data, (2) abundance trends, (3) the
relationship between decline and recovery, and (4) critical factors
to recovery. I compiled a database of 143 population abundance time
series. Using robust linear regression, I found approximately one
third (35%) were significantly increasing and recovering. For
populations with historical estimates (n=47), I also found a
negative relationship between decline and recovery. With the
significant population trends (n=43), I used a variety of modeling
approaches—classification trees, generalized linear models (GLMs)
and generalized additive models (GAMs) —to assess the relationship
between hypothesized intrinsic and extrinsic critical factors and
recovery. The results suggest the ongoing importance of wildlife
proximity and accessibility to humans in determining population
recovery.
Advisors/Committee Members: Dr. Tim Gerrodette (external-examiner), Dr. Hal Whitehead (graduate-coordinator), Dr. Jeff Hutchings (thesis-reader), Dr. Hal Whitehead (thesis-reader), Dr. Heike Lotze & Dr. Joanna Mills Flemming (thesis-supervisor), Not Applicable (ethics-approval), Yes (manuscripts), Not Applicable (copyright-release).
Subjects/Keywords: marine; mammal; recovery; conservation; management; trend; model
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APA (6th Edition):
Magera, A. M. (2011). Marine Mammal Population Recoveries and Critical
Factors. (Masters Thesis). Dalhousie University. Retrieved from http://hdl.handle.net/10222/13330
Chicago Manual of Style (16th Edition):
Magera, Anna M. “Marine Mammal Population Recoveries and Critical
Factors.” 2011. Masters Thesis, Dalhousie University. Accessed April 12, 2021.
http://hdl.handle.net/10222/13330.
MLA Handbook (7th Edition):
Magera, Anna M. “Marine Mammal Population Recoveries and Critical
Factors.” 2011. Web. 12 Apr 2021.
Vancouver:
Magera AM. Marine Mammal Population Recoveries and Critical
Factors. [Internet] [Masters thesis]. Dalhousie University; 2011. [cited 2021 Apr 12].
Available from: http://hdl.handle.net/10222/13330.
Council of Science Editors:
Magera AM. Marine Mammal Population Recoveries and Critical
Factors. [Masters Thesis]. Dalhousie University; 2011. Available from: http://hdl.handle.net/10222/13330
Dalhousie University
7.
Davies, Trevor.
Population Status of Exploited Marine Fish
Populations.
Degree: PhD, Department of Biology, 2014, Dalhousie University
URL: http://hdl.handle.net/10222/56042
► Estimating the population status and trajectory of marine fishes is hampered by limited data and the assumptions needed to augment these data gaps can have…
(more)
▼ Estimating the population status and trajectory of
marine fishes is hampered by limited data and the assumptions
needed to augment these data gaps can have broad implications. Poor
management decisions based on poor inference can have far reaching
socio-economic and ecosystem consequences. Here, I examine critical
assumptions commonly employed in fisheries models and how they
affect our beliefs on the population status of exploited marine
fisheries. The assumption that catch rates are proportional to
abundance is a critical assumption that can influence estimates of
stock status. In chapter 3, this assumption is evaluated via a
state-space modelling framework to obtain better estimates of the
stock status of cusk (Brosme brosme) by incorporating multiple
population time series in the estimation of population biomass. By
relaxing the assumption that catch rates were directly proportional
to population biomass, I found that the research trawl survey was
likely hyperdepleted, thus exaggerating estimates of population
decline. Indeed, previous estimates of population decline based
solely on the the research trawl survey were 93% compared to my
estimate of 64% once non-proportionality was incorporated in the
modelling structure. In chapter 4, I model the spatial distribution
and population trajectory of different size classes of thorny skate
(Amblyraja radiata) to test for density dependent habitat selection
(DDHS). I found large declines in both abundance and distribution
for all size classes with the greatest declines observed in large
juvenile and adult size classes. I found strong evidence for DDHS
for the large juvenile and adult size classes, however, small
juveniles exhibited limited changes in distribution associated with
changes in abundance. In chapter 5, I examine how biological
reference points used by fisheries to monitor harvest
sustainability compare to those developed by conservation
organizations, such as the IUCN Red List, to estimate extinction
risk. I show that the two approaches frequently arrive at similar
categorizations of stock status and differences are primarily a
result of decline thresholds used to trigger conservation action.
Conservation and fisheries metrics aligned well (70.5% to 80.7% for
riskier and more conservative reference points respectively)
despite their mathematical disconnect in decline thresholds. My
analyses suggest conservation and fisheries scientists will agree
on the status of exploited marine fishes in most cases, leaving
only the question of appropriate management responses for
populations of mutual concern still unresolved.
Advisors/Committee Members: Dr. Olaf P. Jensen (external-examiner), Dr. Hal Whitehead (graduate-coordinator), Dr. Joanna Mills Flemming (thesis-reader), Dr. Sandra Walde (thesis-reader), Dr. Ian Jonsen (thesis-reader), Dr. Hal Whitehead (thesis-supervisor), Dr. Doug Swain (thesis-supervisor), Not Applicable (ethics-approval), Yes (manuscripts), Not Applicable (copyright-release).
Subjects/Keywords: fisheries; data poor; cusk; reference points
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APA (6th Edition):
Davies, T. (2014). Population Status of Exploited Marine Fish
Populations. (Doctoral Dissertation). Dalhousie University. Retrieved from http://hdl.handle.net/10222/56042
Chicago Manual of Style (16th Edition):
Davies, Trevor. “Population Status of Exploited Marine Fish
Populations.” 2014. Doctoral Dissertation, Dalhousie University. Accessed April 12, 2021.
http://hdl.handle.net/10222/56042.
MLA Handbook (7th Edition):
Davies, Trevor. “Population Status of Exploited Marine Fish
Populations.” 2014. Web. 12 Apr 2021.
Vancouver:
Davies T. Population Status of Exploited Marine Fish
Populations. [Internet] [Doctoral dissertation]. Dalhousie University; 2014. [cited 2021 Apr 12].
Available from: http://hdl.handle.net/10222/56042.
Council of Science Editors:
Davies T. Population Status of Exploited Marine Fish
Populations. [Doctoral Dissertation]. Dalhousie University; 2014. Available from: http://hdl.handle.net/10222/56042
Dalhousie University
8.
MacDonald, William.
GENOMIC IMPRINTING IN Drosophila melanogaster: EPIGENETIC
REGULATION OF THE Dp(1;f)LJ9 IMPRINTED DOMAIN.
Degree: PhD, Department of Biology, 2010, Dalhousie University
URL: http://hdl.handle.net/10222/13023
► Genomic imprinting is an epigenetic phenomenon whereby the expression of a gene, chromosomal region, or entire chromosome, depends on the sex of the transmitting parent.…
(more)
▼ Genomic imprinting is an epigenetic phenomenon whereby
the expression of a gene, chromosomal region, or entire chromosome,
depends on the sex of the transmitting parent. Imprinting results
in an otherwise fully functional gene being transcriptionally
silenced when transmitted by one parent, yet the same gene, with
identical DNA sequence, is active when transmitted by the other.
Thus, the gene retains an imprint or “memory” of its genetic
history, which is reversible and reset each successive generation
by passage through the germline. Within this thesis, I present my
findings that show genomic imprinting in Drosophila is regulated by
distinct epigenetic mechanisms at different stages of
embryogenesis, suggesting the requirement of a transitional stage
to stabilize the imprint between establishment in the germline and
maintenance in the soma. I futher show that Drosophila utilize
epigenetic mechanisms that are involved in regulating genomic
imprinting in mammals and plants, such as DNA methylation, histone
modification, antisense RNA, and chromatin insulators. These
findings demonstrate convergence of the epigenetic mechanisms that
regulate genomic imprinting in diverse organisms.
Advisors/Committee Members: Dr. Denise Clark (external-examiner), Dr. Hal Whitehead (graduate-coordinator), Dr. Mark Johnston (thesis-reader), Dr. Bill Pohajdak (thesis-reader), Dr. Vett Lloyd (thesis-supervisor), Not Applicable (ethics-approval), Yes (manuscripts), Yes (copyright-release).
Subjects/Keywords: Drosophila; Imprinting; Epigenetics
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APA (6th Edition):
MacDonald, W. (2010). GENOMIC IMPRINTING IN Drosophila melanogaster: EPIGENETIC
REGULATION OF THE Dp(1;f)LJ9 IMPRINTED DOMAIN. (Doctoral Dissertation). Dalhousie University. Retrieved from http://hdl.handle.net/10222/13023
Chicago Manual of Style (16th Edition):
MacDonald, William. “GENOMIC IMPRINTING IN Drosophila melanogaster: EPIGENETIC
REGULATION OF THE Dp(1;f)LJ9 IMPRINTED DOMAIN.” 2010. Doctoral Dissertation, Dalhousie University. Accessed April 12, 2021.
http://hdl.handle.net/10222/13023.
MLA Handbook (7th Edition):
MacDonald, William. “GENOMIC IMPRINTING IN Drosophila melanogaster: EPIGENETIC
REGULATION OF THE Dp(1;f)LJ9 IMPRINTED DOMAIN.” 2010. Web. 12 Apr 2021.
Vancouver:
MacDonald W. GENOMIC IMPRINTING IN Drosophila melanogaster: EPIGENETIC
REGULATION OF THE Dp(1;f)LJ9 IMPRINTED DOMAIN. [Internet] [Doctoral dissertation]. Dalhousie University; 2010. [cited 2021 Apr 12].
Available from: http://hdl.handle.net/10222/13023.
Council of Science Editors:
MacDonald W. GENOMIC IMPRINTING IN Drosophila melanogaster: EPIGENETIC
REGULATION OF THE Dp(1;f)LJ9 IMPRINTED DOMAIN. [Doctoral Dissertation]. Dalhousie University; 2010. Available from: http://hdl.handle.net/10222/13023
Dalhousie University
9.
Bay, Rachael.
Analysis of Functional Constraint and Recombination in Gene
Sequences of the Cyanobacteria Prochlorococcus.
Degree: MS, Department of Biology, 2010, Dalhousie University
URL: http://hdl.handle.net/10222/13021
► Lineages of the cyanobacteria Prochlorococcus marinus have diverged into two genetically distinct ‘ecotypes,’ high-light adapted (HL) and low-light adapted (LL), which thrive under different environmental…
(more)
▼ Lineages of the cyanobacteria Prochlorococcus marinus
have diverged into two genetically distinct ‘ecotypes,’ high-light
adapted (HL) and low-light adapted (LL), which thrive under
different environmental conditions. This type of niche
differentiation in prokaryotes is often accompanied by genetic and
genomic divergence. Differential selection pressure associated with
ecotype divergence can be analyzed using models of codon evolution.
However, some characteristics of the Prochlorococcus genome violate
underlying assumptions of these models. For example, high levels of
recombination between bacterial strains are known to cause false
positives for codon models. Therefore, it is important that
statistical methods for detecting recombination be reliable. In
Chapter 2, I evaluate a set of recombination detection methods
under four different scenarios related to functional divergence: 1)
varying tree shape, 2) positive selection, 3) non-stationary
evolution, and 4) varying levels of recombination and
divergence.
Advisors/Committee Members: Dr. Jonathan Wright (external-examiner), Dr. Hal Whitehead (graduate-coordinator), Dr. Katherine Dunn (thesis-reader), Dr. Andrew Roger (thesis-reader), Dr. Joseph Bielawski (thesis-supervisor), Not Applicable (ethics-approval), Not Applicable (manuscripts), Not Applicable (copyright-release).
Subjects/Keywords: Cyanobacteria; Recombination; Natural Selection
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APA (6th Edition):
Bay, R. (2010). Analysis of Functional Constraint and Recombination in Gene
Sequences of the Cyanobacteria Prochlorococcus. (Masters Thesis). Dalhousie University. Retrieved from http://hdl.handle.net/10222/13021
Chicago Manual of Style (16th Edition):
Bay, Rachael. “Analysis of Functional Constraint and Recombination in Gene
Sequences of the Cyanobacteria Prochlorococcus.” 2010. Masters Thesis, Dalhousie University. Accessed April 12, 2021.
http://hdl.handle.net/10222/13021.
MLA Handbook (7th Edition):
Bay, Rachael. “Analysis of Functional Constraint and Recombination in Gene
Sequences of the Cyanobacteria Prochlorococcus.” 2010. Web. 12 Apr 2021.
Vancouver:
Bay R. Analysis of Functional Constraint and Recombination in Gene
Sequences of the Cyanobacteria Prochlorococcus. [Internet] [Masters thesis]. Dalhousie University; 2010. [cited 2021 Apr 12].
Available from: http://hdl.handle.net/10222/13021.
Council of Science Editors:
Bay R. Analysis of Functional Constraint and Recombination in Gene
Sequences of the Cyanobacteria Prochlorococcus. [Masters Thesis]. Dalhousie University; 2010. Available from: http://hdl.handle.net/10222/13021
Dalhousie University
10.
McEachern, Lori A.
INTER-KINGDOM EPIGENETICS: CHARACTERIZATION OF MAIZE B1
TANDEM REPEAT-MEDIATED SILENCING IN DROSOPHILA MELANOGASTER.
Degree: PhD, Department of Biology, 2010, Dalhousie University
URL: http://hdl.handle.net/10222/13036
► Transgenic organisms are a valuable tool for studying epigenetics, as they provide significant insight into the evolutionary conservation of epigenetic control sequences, the interacting proteins,…
(more)
▼ Transgenic organisms are a valuable tool for studying
epigenetics, as they provide significant insight into the
evolutionary conservation of epigenetic control sequences, the
interacting proteins, and the underlying molecular mechanisms.
Paramutation is an epigenetic phenomenon in which the epigenetic
status and expression level of one allele is heritably altered
after pairing with another. At the b1 locus in maize, a control
region consisting of seven 853 bp tandem repeats is required for
paramutation. To study the conservation of the epigenetic
mechanisms underlying maize b1 paramutation, I created transgenic
Drosophila carrying the maize b1 control region flanked by FRT
sites and adjacent to the Drosophila white reporter gene. The maize
b1 tandem repeats caused epigenetic silencing in Drosophila, as
white expression consistently increased following repeat removal. A
single copy of the tandem repeat sequence was sufficient to cause
silencing, and silencing strength increased as the number of
repeats increased. Trans interactions, such as pairing-sensitive
silencing, were also observed and appear to require a threshold
number of b1 tandem repeats, similar to paramutation in maize.
Analysis of transcription from the repeats showed that the b1
tandem repeats are transcribed from both strands in Drosophila, as
they are in maize. Bidirectional transcription was found to extend
to the regions flanking the repeats, and persisted in “repeats-out”
transgenes following repeat removal. However, aberrant
transcription was lost when a zero-repeat transgene was moved to a
new genomic position, suggesting that it may be due to an
epigenetic mark that is retained from the previous silenced state.
A search for modifiers of b1 repeat-mediated silencing demonstrated
that Polycomb group proteins are involved. Together, these results
indicate considerable conservation of an epigenetic silencing
process between the plant and animal kingdoms. Genomic imprinting
is a related epigenetic process in which parent-specific epigenetic
states are inherited and maintained in progeny. The conservation of
epigenetic mechanisms was further explored via an in-depth review
of the molecular mechanisms underlying genomic imprinting in
plants, mammals and insects, and identification of potentially
imprinted genes in Drosophila by microarray analysis.
Advisors/Committee Members: Dr. Lori Wallrath (external-examiner), Dr. Hal Whitehead (graduate-coordinator), Dr. Bill Pohajdak (thesis-reader), Dr. Ian Meinertzhagen (thesis-reader), Dr. Vett Lloyd (thesis-supervisor), Not Applicable (ethics-approval), Yes (manuscripts), Yes (copyright-release).
Subjects/Keywords: Epigenetics; Drosophila melanogaster; Paramutation; Tandem repeats; Transcription; Silencing; Genomic imprinting
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APA ·
Chicago ·
MLA ·
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CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
McEachern, L. A. (2010). INTER-KINGDOM EPIGENETICS: CHARACTERIZATION OF MAIZE B1
TANDEM REPEAT-MEDIATED SILENCING IN DROSOPHILA MELANOGASTER. (Doctoral Dissertation). Dalhousie University. Retrieved from http://hdl.handle.net/10222/13036
Chicago Manual of Style (16th Edition):
McEachern, Lori A. “INTER-KINGDOM EPIGENETICS: CHARACTERIZATION OF MAIZE B1
TANDEM REPEAT-MEDIATED SILENCING IN DROSOPHILA MELANOGASTER.” 2010. Doctoral Dissertation, Dalhousie University. Accessed April 12, 2021.
http://hdl.handle.net/10222/13036.
MLA Handbook (7th Edition):
McEachern, Lori A. “INTER-KINGDOM EPIGENETICS: CHARACTERIZATION OF MAIZE B1
TANDEM REPEAT-MEDIATED SILENCING IN DROSOPHILA MELANOGASTER.” 2010. Web. 12 Apr 2021.
Vancouver:
McEachern LA. INTER-KINGDOM EPIGENETICS: CHARACTERIZATION OF MAIZE B1
TANDEM REPEAT-MEDIATED SILENCING IN DROSOPHILA MELANOGASTER. [Internet] [Doctoral dissertation]. Dalhousie University; 2010. [cited 2021 Apr 12].
Available from: http://hdl.handle.net/10222/13036.
Council of Science Editors:
McEachern LA. INTER-KINGDOM EPIGENETICS: CHARACTERIZATION OF MAIZE B1
TANDEM REPEAT-MEDIATED SILENCING IN DROSOPHILA MELANOGASTER. [Doctoral Dissertation]. Dalhousie University; 2010. Available from: http://hdl.handle.net/10222/13036
Dalhousie University
11.
Tuck, Constance.
Scaling up to food webs: Effects of temperature on structure
and function along a latitudinal gradient.
Degree: MS, Department of Biology, 2010, Dalhousie University
URL: http://hdl.handle.net/10222/13047
► Global warming will affect every level of biological organization from the metabolism of individuals to the functioning of ecosystems. I explored the effects of warming…
(more)
▼ Global warming will affect every level of biological
organization from the metabolism of individuals to the functioning
of ecosystems. I explored the effects of warming on three rock-pool
meioinvertebrate communities along a latitudinal gradient
(temperate, tropical, and sub-Arctic regions) to determine effects
on community and food-web structure and functioning. Warming
affected regions differently, having a positive effect on
sub-Arctic communities, a negative effect on temperate communities,
and intermediate responses in tropical communities in terms of
abundance, stability and extinction frequency. Differences in
structural properties of the food webs supported the insurance
hypothesis: that greater redundancy in webs results in greater
stability, and helped to explain why the tropical community was
more stable than the temperate community in warmed treatments. My
study highlights the importance of considering differential
response of species and communities from different latitudes and
the importance of food web structure in predicting species response
to global climate change.
Advisors/Committee Members: Madhur Anand (external-examiner), Paul Bentzen (graduate-coordinator), Hal Whitehead (thesis-reader), Sina Adl (thesis-reader), Jeffrey Hutchings (thesis-reader), Tamara Romanuk (thesis-supervisor), Not Applicable (ethics-approval), Not Applicable (manuscripts), Not Applicable (copyright-release).
Subjects/Keywords: Food webs; climate change; latitudinal gradient
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APA (6th Edition):
Tuck, C. (2010). Scaling up to food webs: Effects of temperature on structure
and function along a latitudinal gradient. (Masters Thesis). Dalhousie University. Retrieved from http://hdl.handle.net/10222/13047
Chicago Manual of Style (16th Edition):
Tuck, Constance. “Scaling up to food webs: Effects of temperature on structure
and function along a latitudinal gradient.” 2010. Masters Thesis, Dalhousie University. Accessed April 12, 2021.
http://hdl.handle.net/10222/13047.
MLA Handbook (7th Edition):
Tuck, Constance. “Scaling up to food webs: Effects of temperature on structure
and function along a latitudinal gradient.” 2010. Web. 12 Apr 2021.
Vancouver:
Tuck C. Scaling up to food webs: Effects of temperature on structure
and function along a latitudinal gradient. [Internet] [Masters thesis]. Dalhousie University; 2010. [cited 2021 Apr 12].
Available from: http://hdl.handle.net/10222/13047.
Council of Science Editors:
Tuck C. Scaling up to food webs: Effects of temperature on structure
and function along a latitudinal gradient. [Masters Thesis]. Dalhousie University; 2010. Available from: http://hdl.handle.net/10222/13047
Dalhousie University
12.
Campbell, Véronik.
Dynamics of Species Extinction and Recovery in Multi-Trophic
Aquatic Systems.
Degree: MS, Department of Biology, 2010, Dalhousie University
URL: http://hdl.handle.net/10222/13106
► The current rate of species extinction is higher than at any other time in Earth’s history. Despite our understanding of the causes and consequences of…
(more)
▼ The current rate of species extinction is higher than
at any other time in Earth’s history. Despite our understanding of
the causes and consequences of extinction and the development of
numerous species conservation plans, it is surprising how little we
know about the dynamics of extinction and recovery. Here, I explore
the dynamics of population extinction and recovery across a range
of meio-invertebrate species embedded in aquatic multi-trophic
communities under external pressure. My results indicate that
external mortality frequency has a negative impact on the dynamics
of population extinction and recovery and suggest that it may be
possible to predict patterns of population extinction from patterns
of population growth as well as patterns of recovery from patterns
of population collapse. My findings provide a valuable empirical
basis from which we may increase our understanding of the factors
influencing extinction risk and recovery potential to develop
sustainable management strategies.
Advisors/Committee Members: Diane Srivastava (external-examiner), Hal Whitehead (graduate-coordinator), Sina Adl (thesis-reader), Sandra Walde (thesis-reader), Boris Worm (thesis-reader), Tamara Romanuk (thesis-supervisor), Not Applicable (ethics-approval), Not Applicable (manuscripts), Not Applicable (copyright-release).
Subjects/Keywords: Extinction; recovery; population dynamics; collapse;
extinction dynamics; recovery dynamics; zooplankton;
microcosm
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APA ·
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MLA ·
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CSE |
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Manager
APA (6th Edition):
Campbell, V. (2010). Dynamics of Species Extinction and Recovery in Multi-Trophic
Aquatic Systems. (Masters Thesis). Dalhousie University. Retrieved from http://hdl.handle.net/10222/13106
Chicago Manual of Style (16th Edition):
Campbell, Véronik. “Dynamics of Species Extinction and Recovery in Multi-Trophic
Aquatic Systems.” 2010. Masters Thesis, Dalhousie University. Accessed April 12, 2021.
http://hdl.handle.net/10222/13106.
MLA Handbook (7th Edition):
Campbell, Véronik. “Dynamics of Species Extinction and Recovery in Multi-Trophic
Aquatic Systems.” 2010. Web. 12 Apr 2021.
Vancouver:
Campbell V. Dynamics of Species Extinction and Recovery in Multi-Trophic
Aquatic Systems. [Internet] [Masters thesis]. Dalhousie University; 2010. [cited 2021 Apr 12].
Available from: http://hdl.handle.net/10222/13106.
Council of Science Editors:
Campbell V. Dynamics of Species Extinction and Recovery in Multi-Trophic
Aquatic Systems. [Masters Thesis]. Dalhousie University; 2010. Available from: http://hdl.handle.net/10222/13106
Dalhousie University
13.
Yorke, Alana F.
Interactions Between an Invasive Epiphytic Bryozoan and
Species of Rocky Subtidal Habitats of Nova Scotia.
Degree: MS, Department of Biology, 2010, Dalhousie University
URL: http://hdl.handle.net/10222/13111
► In Nova Scotia subtidal habitats, the invasive bryozoan Membranipora membranacea interacts with native bryozoan Electra pilosa on kelps, which offer high space availability but are…
(more)
▼ In Nova Scotia subtidal habitats, the invasive
bryozoan Membranipora membranacea interacts with native bryozoan
Electra pilosa on kelps, which offer high space availability but
are highly dynamic, and on non-kelp algae, which provide low space
but high stability. Settlers and colony cover of M. membranacea at
various stages critical to its population dynamics, as well as
relative abundance and encounter outcomes of M. membranacea and E.
pilosa, were quantified on these substrates. I also examined the
effects of various factors on growth rates of E. pilosa. For M.
membranacea populations, the roles of kelp and non-kelp substrates
varied intra- and inter-annually, as well as spatially.
Membranipora membranacea was relatively more abundant on kelps than
on Fucus, likely due to large colony size, faster growth, and
strong overgrowth abilities. While kelps provide spatial resources
for seasonal peaks in abundance of M. membranacea, non-kelp refuges
can preserve local populations in time.
Advisors/Committee Members: Ricardo Scrosati (external-examiner), Hal Whitehead (graduate-coordinator), Robert Scheibling (thesis-reader), Sandra Walde (thesis-reader), Claudio DiBacco (thesis-reader), Anna Metaxas (thesis-supervisor), Not Applicable (ethics-approval), Yes (manuscripts), Not Applicable (copyright-release).
Subjects/Keywords: invasive species; population dynamics; benthic colonial organisms; rocky subtidal habitats; Membranipora membranacea; Electra pilosa; fucoids; kelp; native species; growth; competition
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APA (6th Edition):
Yorke, A. F. (2010). Interactions Between an Invasive Epiphytic Bryozoan and
Species of Rocky Subtidal Habitats of Nova Scotia. (Masters Thesis). Dalhousie University. Retrieved from http://hdl.handle.net/10222/13111
Chicago Manual of Style (16th Edition):
Yorke, Alana F. “Interactions Between an Invasive Epiphytic Bryozoan and
Species of Rocky Subtidal Habitats of Nova Scotia.” 2010. Masters Thesis, Dalhousie University. Accessed April 12, 2021.
http://hdl.handle.net/10222/13111.
MLA Handbook (7th Edition):
Yorke, Alana F. “Interactions Between an Invasive Epiphytic Bryozoan and
Species of Rocky Subtidal Habitats of Nova Scotia.” 2010. Web. 12 Apr 2021.
Vancouver:
Yorke AF. Interactions Between an Invasive Epiphytic Bryozoan and
Species of Rocky Subtidal Habitats of Nova Scotia. [Internet] [Masters thesis]. Dalhousie University; 2010. [cited 2021 Apr 12].
Available from: http://hdl.handle.net/10222/13111.
Council of Science Editors:
Yorke AF. Interactions Between an Invasive Epiphytic Bryozoan and
Species of Rocky Subtidal Habitats of Nova Scotia. [Masters Thesis]. Dalhousie University; 2010. Available from: http://hdl.handle.net/10222/13111
Dalhousie University
14.
Mogensen, Stephanie.
Maternal Fitness Consequences of Different Causative Agents
of Offspring Mortality in Early Life.
Degree: MS, Department of Biology, 2010, Dalhousie University
URL: http://hdl.handle.net/10222/13133
► Maternal effects can be key determinants of female fitness through their influence on early life survival. In salmonids, three main sources of mortality in early…
(more)
▼ Maternal effects can be key determinants of female
fitness through their influence on early life survival. In
salmonids, three main sources of mortality in early life can be
attributed to redd superimposition, predation, and starvation
(meditated by territory limitation). The influence of different
agents of mortality will depend on maternal phenotype (e.g. body
size) and within-season reproductive timing. An individual-based
model, incorporating both stochastic and deterministic processes,
was developed to assess how the relationships between maternal
fitness, maternal phenotype (body size) and spawning timing were
affected by these different sources of mortality. I found that
maternal size influenced fitness under some, but not all
circumstances. Larger size was beneficial when predation mortality
was low, territories were limited, and/or spawner density was high.
Spawning time also influenced maternal fitness; early spawned
juveniles were favoured when territories were limited, whereas
later spawned juveniles were favoured when predation mortality was
high. Component Allee effects at low spawned densities were also
detected in some simulations. These results suggest that the
fitness consequences of maternal phenotype depend on the sources of
mortality present. The fact that these context-dependent sources of
offspring mortality in early life may vary between habitats or
between years increases the difficulty in identifying the
correlates of maternal fitness in salmonid fishes.
Advisors/Committee Members: Marco A. Rodríguez (external-examiner), Hal Whitehead (graduate-coordinator), Sandra Walde (thesis-reader), Christophe herbinger (thesis-reader), Jeff Hutchings (thesis-supervisor), Not Applicable (ethics-approval), Not Applicable (manuscripts), Not Applicable (copyright-release).
Subjects/Keywords: Maternal effects; salmonids
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MLA ·
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APA (6th Edition):
Mogensen, S. (2010). Maternal Fitness Consequences of Different Causative Agents
of Offspring Mortality in Early Life. (Masters Thesis). Dalhousie University. Retrieved from http://hdl.handle.net/10222/13133
Chicago Manual of Style (16th Edition):
Mogensen, Stephanie. “Maternal Fitness Consequences of Different Causative Agents
of Offspring Mortality in Early Life.” 2010. Masters Thesis, Dalhousie University. Accessed April 12, 2021.
http://hdl.handle.net/10222/13133.
MLA Handbook (7th Edition):
Mogensen, Stephanie. “Maternal Fitness Consequences of Different Causative Agents
of Offspring Mortality in Early Life.” 2010. Web. 12 Apr 2021.
Vancouver:
Mogensen S. Maternal Fitness Consequences of Different Causative Agents
of Offspring Mortality in Early Life. [Internet] [Masters thesis]. Dalhousie University; 2010. [cited 2021 Apr 12].
Available from: http://hdl.handle.net/10222/13133.
Council of Science Editors:
Mogensen S. Maternal Fitness Consequences of Different Causative Agents
of Offspring Mortality in Early Life. [Masters Thesis]. Dalhousie University; 2010. Available from: http://hdl.handle.net/10222/13133
Dalhousie University
15.
Fairhurst, Elizabeth.
The Effect of Nest Acoustics on the Begging Calls of
Nestling Tree Swallows.
Degree: MS, Department of Biology, 2010, Dalhousie University
URL: http://hdl.handle.net/10222/13135
► Animals’ long-distance acoustic signal structure minimizes habitat-specific attenuation and distortion, but it is unknown how environmental acoustics shape the signals of dependent young, or short-range…
(more)
▼ Animals’ long-distance acoustic signal structure
minimizes habitat-specific attenuation and distortion, but it is
unknown how environmental acoustics shape the signals of dependent
young, or short-range signals generally. I investigated the
influence of the nest environment on nestling tree swallows’
begging calls by relating nest reverberation and resonance to nest
structure; relating call features to nest reverberation, resonance
and structure; and testing whether call structure reduced
distortion in the home nest. Reverberation was stronger in wider
cavities with intact ceilings. Nestlings used shorter calls in more
reverberant cavities, and longer calls with higher middle frequency
and lower minimum frequency in wider cavities with smoother walls,
but did not adjust call frequency in relation to resonance. Calls
originally produced in a given nest did not transmit with less
distortion than calls originally produced in other nests. These
findings suggest that the nest environment may shape the structure
of begging calls.
Advisors/Committee Members: Peter McGregor (external-examiner), Hal Whitehead (graduate-coordinator), Andrew Horn (thesis-reader), Leslie Phillmore (thesis-reader), Marty Leonard (thesis-supervisor), Received (ethics-approval), Not Applicable (manuscripts), Not Applicable (copyright-release).
Subjects/Keywords: acoustics; begging; Tachycineta bicolor
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APA ·
Chicago ·
MLA ·
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Manager
APA (6th Edition):
Fairhurst, E. (2010). The Effect of Nest Acoustics on the Begging Calls of
Nestling Tree Swallows. (Masters Thesis). Dalhousie University. Retrieved from http://hdl.handle.net/10222/13135
Chicago Manual of Style (16th Edition):
Fairhurst, Elizabeth. “The Effect of Nest Acoustics on the Begging Calls of
Nestling Tree Swallows.” 2010. Masters Thesis, Dalhousie University. Accessed April 12, 2021.
http://hdl.handle.net/10222/13135.
MLA Handbook (7th Edition):
Fairhurst, Elizabeth. “The Effect of Nest Acoustics on the Begging Calls of
Nestling Tree Swallows.” 2010. Web. 12 Apr 2021.
Vancouver:
Fairhurst E. The Effect of Nest Acoustics on the Begging Calls of
Nestling Tree Swallows. [Internet] [Masters thesis]. Dalhousie University; 2010. [cited 2021 Apr 12].
Available from: http://hdl.handle.net/10222/13135.
Council of Science Editors:
Fairhurst E. The Effect of Nest Acoustics on the Begging Calls of
Nestling Tree Swallows. [Masters Thesis]. Dalhousie University; 2010. Available from: http://hdl.handle.net/10222/13135
Dalhousie University
16.
Ferretti, Francesco.
THE ROLE OF SHARKS IN MARINE ECOSYSTEMS: EVALUATING
OVEREXPLOITED MARINE FISH COMMUNITIES TO DETECT LONG-TERM EFFECTS
OF PREDATOR REMOVAL.
Degree: PhD, Department of Biology, 2010, Dalhousie University
URL: http://hdl.handle.net/10222/13171
► Elasmobranchs are among the oldest and most successful predators in the ocean, yet one of the most vulnerable to the direct and indirect effects of…
(more)
▼ Elasmobranchs are among the oldest and most successful
predators in the ocean, yet one of the most vulnerable to the
direct and indirect effects of fishing. Many populations are
rapidly declining around the world, and an increasing number is
listed as threatened or endangered. The broader ecosystem
consequences of these declines, and whether other marine predators
can replace sharks, are open questions. In this thesis, I used a
diverse set of data and modeling techniques to analyze long-term
changes in elasmobranch populations in the Mediterranean Sea, and
the consequences of shark declines on marine ecosystems. Because of
its long history of fishing, the Mediterranean offers a unique
perspective on the response of marine communities to exploitation
over long time scales. Here, I reconstructed the history of
elasmobranch exploitation over the past 200 years in pelagic,
coastal and demersal communities. Results were combined
meta-analytically to derive a general pattern of change for the
entire region. Overall, I detected multiple cases of regional
species extirpations, a strong correlation between historical
intensity of exploitation and the stage of community degradation,
and some cases of compensatory species increases. My results
suggest that compared to other marine ecosystems worldwide, the
Mediterranean Sea might be in an advanced stage of
overexploitation. To gain more general conclusions about the
patterns and consequences of shark declines in the ocean, I
reviewed and reanalyzed documented changes in exploited
elasmobranch communities around the world, and synthesized the
effects of sharks on their prey and wider communities. This work
revealed that sharks are abundant and diverse in little exploited
or unexploited marine ecosystems but vulnerable to even light
levels of fishing. The decline in large sharks has reduced natural
mortality in a range of their prey, contributing to changes in
abundance, distribution, and behaviour of marine megafauna that
have few other predators. In some cases, this has resulted in
cascading changes in prey populations and food-web structure.
Overall, my thesis greatly enhanced our knowledge about the
critical state of elasmobranchs in the Mediterranean Sea and the
consequences of the declines of these important marine predators on
marine ecosystems.
Advisors/Committee Members: Jeremy Collie (external-examiner), Hal Whitehead (graduate-coordinator), Boris Worm (thesis-reader), Edward Susko (thesis-reader), Heike K. Lotze and Andrew A. Rosenberg (thesis-supervisor), Not Applicable (ethics-approval), Yes (manuscripts), Yes (copyright-release).
Subjects/Keywords: Elasmobranchs; extinction risk; generalized linear models;
historical population trends; meta-analysis; overfishing;
predators; top-down control; ecological role; ecosystem; fishing;
mesopredator release; predation; risk effects; trophic cascades;
sharks; trawl surveys
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APA (6th Edition):
Ferretti, F. (2010). THE ROLE OF SHARKS IN MARINE ECOSYSTEMS: EVALUATING
OVEREXPLOITED MARINE FISH COMMUNITIES TO DETECT LONG-TERM EFFECTS
OF PREDATOR REMOVAL. (Doctoral Dissertation). Dalhousie University. Retrieved from http://hdl.handle.net/10222/13171
Chicago Manual of Style (16th Edition):
Ferretti, Francesco. “THE ROLE OF SHARKS IN MARINE ECOSYSTEMS: EVALUATING
OVEREXPLOITED MARINE FISH COMMUNITIES TO DETECT LONG-TERM EFFECTS
OF PREDATOR REMOVAL.” 2010. Doctoral Dissertation, Dalhousie University. Accessed April 12, 2021.
http://hdl.handle.net/10222/13171.
MLA Handbook (7th Edition):
Ferretti, Francesco. “THE ROLE OF SHARKS IN MARINE ECOSYSTEMS: EVALUATING
OVEREXPLOITED MARINE FISH COMMUNITIES TO DETECT LONG-TERM EFFECTS
OF PREDATOR REMOVAL.” 2010. Web. 12 Apr 2021.
Vancouver:
Ferretti F. THE ROLE OF SHARKS IN MARINE ECOSYSTEMS: EVALUATING
OVEREXPLOITED MARINE FISH COMMUNITIES TO DETECT LONG-TERM EFFECTS
OF PREDATOR REMOVAL. [Internet] [Doctoral dissertation]. Dalhousie University; 2010. [cited 2021 Apr 12].
Available from: http://hdl.handle.net/10222/13171.
Council of Science Editors:
Ferretti F. THE ROLE OF SHARKS IN MARINE ECOSYSTEMS: EVALUATING
OVEREXPLOITED MARINE FISH COMMUNITIES TO DETECT LONG-TERM EFFECTS
OF PREDATOR REMOVAL. [Doctoral Dissertation]. Dalhousie University; 2010. Available from: http://hdl.handle.net/10222/13171
Dalhousie University
17.
Beazley, Lindsay.
Reproductive Biology of the Deep-Water Gorgonian Coral
Acanella arbuscula from the Northwest Atlantic.
Degree: MS, Department of Biology, 2011, Dalhousie University
URL: http://hdl.handle.net/10222/13265
► This thesis examined the reproductive biology of the poorly-known deep-water gorgonian Acanella arbuscula from the Northwest Atlantic. Colonies were collected from The Gully in 2007…
(more)
▼ This thesis examined the reproductive biology of the
poorly-known deep-water gorgonian Acanella arbuscula from the
Northwest Atlantic. Colonies were collected from The Gully in 2007
and 2010 between 914 and 1860 m depth, and the Flemish Cap in 2009
between 671 and 1264 m. Mean polyp fecundity was relatively high
for both females and males, and the large oocyte size suggests that
A. arbuscula produces lecithotrophic larvae. This species may have
overlapping periodic or seasonal cycles of gametogenesis, and the
absence of planulae suggests that A. arbuscula is a broadcast
spawner. No spatial variation in the reproductive characteristics
of this species was found, suggesting that environmental conditions
are similar between the two sites. Female polyp fecundity decreased
with increasing depth, which may be due to the high cost of
producing oocytes versus sperm. The relatively high mean polyp
fecundity, probable lecithotrophic larval development, and
broadcast spawning may allow for the wide dispersal and settlement
of A. arbuscula across the North Atlantic.
Advisors/Committee Members: Paul A. Tyler (external-examiner), Hal Whitehead (graduate-coordinator), Roger Croll, Anna Metaxas, Ellen Kenchington (thesis-reader), Ellen Kenchington (thesis-supervisor), Not Applicable (ethics-approval), Not Applicable (manuscripts), Not Applicable (copyright-release).
Subjects/Keywords: Deep-water; Gorgonian; Coral; Reproduction;
Histology
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APA (6th Edition):
Beazley, L. (2011). Reproductive Biology of the Deep-Water Gorgonian Coral
Acanella arbuscula from the Northwest Atlantic. (Masters Thesis). Dalhousie University. Retrieved from http://hdl.handle.net/10222/13265
Chicago Manual of Style (16th Edition):
Beazley, Lindsay. “Reproductive Biology of the Deep-Water Gorgonian Coral
Acanella arbuscula from the Northwest Atlantic.” 2011. Masters Thesis, Dalhousie University. Accessed April 12, 2021.
http://hdl.handle.net/10222/13265.
MLA Handbook (7th Edition):
Beazley, Lindsay. “Reproductive Biology of the Deep-Water Gorgonian Coral
Acanella arbuscula from the Northwest Atlantic.” 2011. Web. 12 Apr 2021.
Vancouver:
Beazley L. Reproductive Biology of the Deep-Water Gorgonian Coral
Acanella arbuscula from the Northwest Atlantic. [Internet] [Masters thesis]. Dalhousie University; 2011. [cited 2021 Apr 12].
Available from: http://hdl.handle.net/10222/13265.
Council of Science Editors:
Beazley L. Reproductive Biology of the Deep-Water Gorgonian Coral
Acanella arbuscula from the Northwest Atlantic. [Masters Thesis]. Dalhousie University; 2011. Available from: http://hdl.handle.net/10222/13265
Dalhousie University
18.
Robinson, Sarah L.
ECOSYSTEM FUNCTIONS AND PLANT COMMUNITY STRUCTURE OF URBAN
SPONTANEOUS VEGETATION.
Degree: MS, Department of Biology, 2011, Dalhousie University
URL: http://hdl.handle.net/10222/13425
► This thesis set out to investigate the processes that determine the richness and composition of plant communities of spontaneously colonized derelict land in Metro Halifax,…
(more)
▼ This thesis set out to investigate the processes that
determine the richness and composition of plant communities of
spontaneously colonized derelict land in Metro Halifax, Nova
Scotia. As urbanization rates continue to rise urban spontaneous
vegetation (USV) communities are becoming more common. While
typically considered to have no or negative economic value, USV
contributes to a variety of ecosystem services not captured in
current urban ecosystem models. Vascular plant composition and
aboitic conditions of three urban communities (USV, forest and
lawn) are described in Chapter 2. USV is diverse and unique, but
the abiotic variables measured were not strong predictors of plant
diversity. In Chapter 3, ecosystem services provided by the three
urban habitats were quantified and compared, showing USV provides
several ecosystem services that complement other urban habitats.
Studies of urban biodiversity aid in the understanding of the
effects of urbanization on biota and serve as a foundation for
encouraging diverse communities of organisms within cities. Factors
influencing the distribution and composition of USV communities
could be vital for preserving native species by incorporating such
knowledge into planning and urban development systems. USV should
be considered an asset to urban greening initiatives, providing a
low-cost, low maintenance approach to landscape planning, while
providing a number of ecosystem benefits not provided by
traditional elements of landscape design.
Advisors/Committee Members: Dr. Roy Montgomery (external-examiner), Dr. Hal Whitehead (graduate-coordinator), Dr. Bill Freedman (thesis-reader), Dr. Bob Latta (thesis-reader), Dr. Jeremy Lundholm (thesis-supervisor), Not Applicable (ethics-approval), Yes (manuscripts), Not Applicable (copyright-release).
Subjects/Keywords: Urban biodiversity; brownfield
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MLA ·
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CSE |
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APA (6th Edition):
Robinson, S. L. (2011). ECOSYSTEM FUNCTIONS AND PLANT COMMUNITY STRUCTURE OF URBAN
SPONTANEOUS VEGETATION. (Masters Thesis). Dalhousie University. Retrieved from http://hdl.handle.net/10222/13425
Chicago Manual of Style (16th Edition):
Robinson, Sarah L. “ECOSYSTEM FUNCTIONS AND PLANT COMMUNITY STRUCTURE OF URBAN
SPONTANEOUS VEGETATION.” 2011. Masters Thesis, Dalhousie University. Accessed April 12, 2021.
http://hdl.handle.net/10222/13425.
MLA Handbook (7th Edition):
Robinson, Sarah L. “ECOSYSTEM FUNCTIONS AND PLANT COMMUNITY STRUCTURE OF URBAN
SPONTANEOUS VEGETATION.” 2011. Web. 12 Apr 2021.
Vancouver:
Robinson SL. ECOSYSTEM FUNCTIONS AND PLANT COMMUNITY STRUCTURE OF URBAN
SPONTANEOUS VEGETATION. [Internet] [Masters thesis]. Dalhousie University; 2011. [cited 2021 Apr 12].
Available from: http://hdl.handle.net/10222/13425.
Council of Science Editors:
Robinson SL. ECOSYSTEM FUNCTIONS AND PLANT COMMUNITY STRUCTURE OF URBAN
SPONTANEOUS VEGETATION. [Masters Thesis]. Dalhousie University; 2011. Available from: http://hdl.handle.net/10222/13425
Dalhousie University
19.
Reynolds, Craig.
The Effect of Acidification on the Survival of American
Eel.
Degree: MS, Department of Biology, 2011, Dalhousie University
URL: http://hdl.handle.net/10222/13573
► The geographic range of the panmictic American eel (Anguilla rostrata) has contracted in recent years because of the pronounced decline in recruitment of glass eels…
(more)
▼ The geographic range of the panmictic American eel
(Anguilla rostrata) has contracted in recent years because of the
pronounced decline in recruitment of glass eels and elvers to the
Laurentian Basin. In consequence, the American eel was assessed in
2006 as a species of special concern by the Committee on the Status
of Endangered Wildlife in Canada (COSEWIC). The evident sensitivity
of American eel status to elver recruitment highlights the
importance of understanding both the mechanisms contributing to the
delivery of glass eels from the Sargasso Sea to continental waters
and mortality following their recruitment to coastal and inland
waterways. The potential for variability in environmental quality
at localized geographic scales to affect American eel productivity
and hence the status of the species and the fisheries it supports
is not fully understood. The Atlantic coast of Nova Scotia is an
ideal location to examine the relationship between water quality
and American eel productivity. Within Nova Scotia there is wide
natural variation in freshwater pH, which has been further
increased in recent years by the effects of acid precipitation.
This variation occurs over a small geographic range of several
hundred kilometres that overlaps an area of high elver influx. As
low environmental pH is known to adversely affect aquatic
ecosystems, it has been identified as a possible threat to elver
survival. In this study, the effect of low pH on elver survival was
examined in both laboratory and field based trials using wild glass
eel/elvers that were captured upon entry to fresh water. Trials
examined the mortality rate of elvers at pH levels within the range
of 4.0 - 7.0 over a 10 day period. The relationship between elver
development and mortality at low pH was also examined through
pigmentation analysis. Laboratory and field based studies resulted
in zero mortality among elvers in natural and artificial acidic
environments with pH levels as low as 4.0., thus indicating that
the American eel is fully acid tolerant upon initial migration into
fresh water. Sub-lethal effects of acidification were explored by
examining the hematological parameters of river resident
yellow-phase American eels exposed to varying levels of acidity in
the laboratory. The level of acidification proved not to be a
factor in determining both hematocrit and blood plasma osmolarity
levels, as there were no significant differences in these variables
between eels exposed to acidic conditions and those exposed to
control neutral pH conditions. These results suggest that through
the use of a highly effective mechanism for regulating blood ion
concentration, the eel is able to tolerate low pH
conditions.
Advisors/Committee Members: Dr. David Cairns (external-examiner), Dr. Hal Whitehead (graduate-coordinator), Dr. Rod Bradford (thesis-reader), Dr. Daniel Ruzzante (thesis-reader), Dr. Paul Bentzen (thesis-supervisor), Not Applicable (ethics-approval), Not Applicable (manuscripts), Not Applicable (copyright-release).
Subjects/Keywords: American Eel; Acidification; Conservation
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APA ·
Chicago ·
MLA ·
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CSE |
Export
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Manager
APA (6th Edition):
Reynolds, C. (2011). The Effect of Acidification on the Survival of American
Eel. (Masters Thesis). Dalhousie University. Retrieved from http://hdl.handle.net/10222/13573
Chicago Manual of Style (16th Edition):
Reynolds, Craig. “The Effect of Acidification on the Survival of American
Eel.” 2011. Masters Thesis, Dalhousie University. Accessed April 12, 2021.
http://hdl.handle.net/10222/13573.
MLA Handbook (7th Edition):
Reynolds, Craig. “The Effect of Acidification on the Survival of American
Eel.” 2011. Web. 12 Apr 2021.
Vancouver:
Reynolds C. The Effect of Acidification on the Survival of American
Eel. [Internet] [Masters thesis]. Dalhousie University; 2011. [cited 2021 Apr 12].
Available from: http://hdl.handle.net/10222/13573.
Council of Science Editors:
Reynolds C. The Effect of Acidification on the Survival of American
Eel. [Masters Thesis]. Dalhousie University; 2011. Available from: http://hdl.handle.net/10222/13573
Dalhousie University
20.
Reithmeier, Laura.
Facilitation of Ectomycorrhizal Colonization of Picea
mariana by Alternate Host Plants above Treeline.
Degree: MS, Department of Biology, 2011, Dalhousie University
URL: http://hdl.handle.net/10222/14144
► The availability of ectomycorrhizal fungi (ECMF) to conifer seedlings above the present treeline is likely related to the presence of alternate ECMF host plants, including…
(more)
▼ The availability of ectomycorrhizal fungi (ECMF) to
conifer seedlings above the present treeline is likely related to
the presence of alternate ECMF host plants, including Betula
glandulosa, Arctostaphylos alpina, and Salix herbacea. The ECMF
inoculum potential of soils from above treeline that either
supported (host) or lacked (non-host) an alternate host plant was
assessed by growing Picea mariana as ECMF bait seedlings in
field-collected soils under controlled conditions. Seedlings became
colonized when grown in both host and non-host soils, but ECMF
percent colonization, richness, and diversity were higher for those
grown in host soils. The ECMF community in Arctostaphylos host
soils was most similar to the community in forest soils. Seedling
growth varied among the different soil types, but was mainly
influenced by percent ECMF colonization and soil nutrients.
Alternate ECMF host plants will likely act as important sources of
fungal inoculum, potentially improving conifer seedling
establishment and growth.
Advisors/Committee Members: Dr. Keith Egger (external-examiner), Dr. Hal Whitehead (graduate-coordinator), Dr. Sina Adl (thesis-reader), Dr. Robert Latta (thesis-reader), Dr. Gavin Kernaghan (thesis-supervisor), Not Applicable (ethics-approval), Not Applicable (manuscripts), Not Applicable (copyright-release).
Subjects/Keywords: Mycorrhizae; Black spruce; Climate change; Forest migration; Labrador Highlands
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APA (6th Edition):
Reithmeier, L. (2011). Facilitation of Ectomycorrhizal Colonization of Picea
mariana by Alternate Host Plants above Treeline. (Masters Thesis). Dalhousie University. Retrieved from http://hdl.handle.net/10222/14144
Chicago Manual of Style (16th Edition):
Reithmeier, Laura. “Facilitation of Ectomycorrhizal Colonization of Picea
mariana by Alternate Host Plants above Treeline.” 2011. Masters Thesis, Dalhousie University. Accessed April 12, 2021.
http://hdl.handle.net/10222/14144.
MLA Handbook (7th Edition):
Reithmeier, Laura. “Facilitation of Ectomycorrhizal Colonization of Picea
mariana by Alternate Host Plants above Treeline.” 2011. Web. 12 Apr 2021.
Vancouver:
Reithmeier L. Facilitation of Ectomycorrhizal Colonization of Picea
mariana by Alternate Host Plants above Treeline. [Internet] [Masters thesis]. Dalhousie University; 2011. [cited 2021 Apr 12].
Available from: http://hdl.handle.net/10222/14144.
Council of Science Editors:
Reithmeier L. Facilitation of Ectomycorrhizal Colonization of Picea
mariana by Alternate Host Plants above Treeline. [Masters Thesis]. Dalhousie University; 2011. Available from: http://hdl.handle.net/10222/14144
Dalhousie University
21.
Wright, Charles Stewart IV.
A STUDY OF THE ROLE OF INTRAGUILD PREDATION IN THE
POPULATION DYNAMICS OF THREE SPECIES OF RHYACOPHILA.
Degree: MS, Department of Biology, 2011, Dalhousie University
URL: http://hdl.handle.net/10222/14146
► Intraguild (IG) predation, where species within the same guild prey on each other, is common in aquatic communities. I used the abundance and distributional patterns…
(more)
▼ Intraguild (IG) predation, where species within the
same guild prey on each other, is common in aquatic communities. I
used the abundance and distributional patterns of three species of
Rhyacophila (Trichoptera), derived from a survey of 25 streams in
Nova Scotia, Canada, to test several predictions of IG theory. I
first sampled microhabitats and conducted behavioural observations
to establish that the species do co-occur and prey on each other.
Abundance patterns did not conform to two key model predictions:
(1) Neither of the IG prey (R. minor, R. vibox) was excluded from
the most productive streams, and (2) IG prey densities were not
inversely related to productivity in streams with the IG predator
(R. fuscula). It remains possible that intraguild predation occurs
between these species of Rhyacophilia, the measured abundances do
not indicate any measurable effects from IGP, the abundance being
determined instead by the availability of prey.
Advisors/Committee Members: Donna Giberson (external-examiner), Hal Whitehead (graduate-coordinator), Cindy Staicer (thesis-reader), Patricia Lane (thesis-reader), Sandra Walde (thesis-supervisor), Not Applicable (ethics-approval), Not Applicable (manuscripts), Not Applicable (copyright-release).
Subjects/Keywords: Biology; streams; predation; intraguild
predation
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APA ·
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MLA ·
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APA (6th Edition):
Wright, C. S. I. (2011). A STUDY OF THE ROLE OF INTRAGUILD PREDATION IN THE
POPULATION DYNAMICS OF THREE SPECIES OF RHYACOPHILA. (Masters Thesis). Dalhousie University. Retrieved from http://hdl.handle.net/10222/14146
Chicago Manual of Style (16th Edition):
Wright, Charles Stewart IV. “A STUDY OF THE ROLE OF INTRAGUILD PREDATION IN THE
POPULATION DYNAMICS OF THREE SPECIES OF RHYACOPHILA.” 2011. Masters Thesis, Dalhousie University. Accessed April 12, 2021.
http://hdl.handle.net/10222/14146.
MLA Handbook (7th Edition):
Wright, Charles Stewart IV. “A STUDY OF THE ROLE OF INTRAGUILD PREDATION IN THE
POPULATION DYNAMICS OF THREE SPECIES OF RHYACOPHILA.” 2011. Web. 12 Apr 2021.
Vancouver:
Wright CSI. A STUDY OF THE ROLE OF INTRAGUILD PREDATION IN THE
POPULATION DYNAMICS OF THREE SPECIES OF RHYACOPHILA. [Internet] [Masters thesis]. Dalhousie University; 2011. [cited 2021 Apr 12].
Available from: http://hdl.handle.net/10222/14146.
Council of Science Editors:
Wright CSI. A STUDY OF THE ROLE OF INTRAGUILD PREDATION IN THE
POPULATION DYNAMICS OF THREE SPECIES OF RHYACOPHILA. [Masters Thesis]. Dalhousie University; 2011. Available from: http://hdl.handle.net/10222/14146
Dalhousie University
22.
MacEachern, Kathryn Anne.
A Comparison of Categorical vs. Fractional Parental
Allocation Based on Microsatellite Markers to Estimate Reproductive
Success and Inbreeding Levels Over Three Generations of Selective
Breeding in a Closed Population of Rainbow Trout (Oncorhynchus
mykiss).
Degree: MS, Department of Biology, 2011, Dalhousie University
URL: http://hdl.handle.net/10222/14356
► MSc Thesis
The aim of this project was to assess three DNA-marker based pedigree reconstruction approaches and their associated challenges, strengths and weaknesses by conducting…
(more)
▼ MSc Thesis
The aim of this project was to assess three DNA-marker
based pedigree reconstruction approaches and their associated
challenges, strengths and weaknesses by conducting a retrospective
analysis of a real, three generation rainbow trout (Oncorhynchus
mykiss) pedigree from the SPA hatchery. Molecular genetic data at
as few as three or four loci was used to infer relatedness among
individuals and between generations in the reconstruction of the
three full pedigrees. Parentage and pedigree reconstruction was
estimated, for the quasi-categorical (exclusion-based and
LOD-based) approaches via the program CERVUS 3.0 and for the
fractional approach via a software (PIPEDIGREE), developed for this
project. The fractional pedigree method appeared superior,
particularly for the estimation of inbreeding levels. This
retrospective analysis was able to demonstrate, under different
pedigree reconstruction approaches, that the semi-selective,
on-farm breeding scheme implemented at the time was successful in
limiting the level of inbreeding increase and identifying possibly
superior broodstock.
Advisors/Committee Members: N/A (external-examiner), Hal Whitehead (graduate-coordinator), Daniel Ruzzante (thesis-reader), Paul Bentzen (thesis-reader), Christophe Herbinger (thesis-supervisor), Not Applicable (ethics-approval), Not Applicable (manuscripts), Not Applicable (copyright-release).
Subjects/Keywords: Subject Not Available
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APA ·
Chicago ·
MLA ·
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Manager
APA (6th Edition):
MacEachern, K. A. (2011). A Comparison of Categorical vs. Fractional Parental
Allocation Based on Microsatellite Markers to Estimate Reproductive
Success and Inbreeding Levels Over Three Generations of Selective
Breeding in a Closed Population of Rainbow Trout (Oncorhynchus
mykiss). (Masters Thesis). Dalhousie University. Retrieved from http://hdl.handle.net/10222/14356
Chicago Manual of Style (16th Edition):
MacEachern, Kathryn Anne. “A Comparison of Categorical vs. Fractional Parental
Allocation Based on Microsatellite Markers to Estimate Reproductive
Success and Inbreeding Levels Over Three Generations of Selective
Breeding in a Closed Population of Rainbow Trout (Oncorhynchus
mykiss).” 2011. Masters Thesis, Dalhousie University. Accessed April 12, 2021.
http://hdl.handle.net/10222/14356.
MLA Handbook (7th Edition):
MacEachern, Kathryn Anne. “A Comparison of Categorical vs. Fractional Parental
Allocation Based on Microsatellite Markers to Estimate Reproductive
Success and Inbreeding Levels Over Three Generations of Selective
Breeding in a Closed Population of Rainbow Trout (Oncorhynchus
mykiss).” 2011. Web. 12 Apr 2021.
Vancouver:
MacEachern KA. A Comparison of Categorical vs. Fractional Parental
Allocation Based on Microsatellite Markers to Estimate Reproductive
Success and Inbreeding Levels Over Three Generations of Selective
Breeding in a Closed Population of Rainbow Trout (Oncorhynchus
mykiss). [Internet] [Masters thesis]. Dalhousie University; 2011. [cited 2021 Apr 12].
Available from: http://hdl.handle.net/10222/14356.
Council of Science Editors:
MacEachern KA. A Comparison of Categorical vs. Fractional Parental
Allocation Based on Microsatellite Markers to Estimate Reproductive
Success and Inbreeding Levels Over Three Generations of Selective
Breeding in a Closed Population of Rainbow Trout (Oncorhynchus
mykiss). [Masters Thesis]. Dalhousie University; 2011. Available from: http://hdl.handle.net/10222/14356
Dalhousie University
23.
AuCoin, Lacey R.
Fractionation of carbon isotopes during fatty acid
metabolism in Atlantic pollock (Pollachius virens).
Degree: MS, Department of Biology, 2011, Dalhousie University
URL: http://hdl.handle.net/10222/14370
► Feeding experiments were conducted on Atlantic pollock (Pollachius virens) to examine the variability in tissue fatty acid (FA) composition and stable carbon isotope fractionation of…
(more)
▼ Feeding experiments were conducted on Atlantic pollock
(Pollachius virens) to examine the variability in tissue fatty acid
(FA) composition and stable carbon isotope fractionation of FA
during digestion, assimilation and mobilization of lipids. The FA
profiles and compound-specific carbon isotopes of chylomicrons,
liver, muscle and fasted serum were compared to diet. FA analysis
demonstrated similarity among tissue groups despite differences in
feeding states. The FA results indicate the blood of post-prandial
fish may serve as an alternative to tissue biopsies for the
estimation of marine fish diets with compound-specific isotope
analysis (CSIA). Despite similarity among FA profiles, the carbon
isotope discrimination factors of FA varied independently, which
suggests that fractionation is influenced by the degree to which
individual FA are oxidized. These results provide preliminary
information that is necessary in order to use CSIA to estimate the
effects of fish diets.
Advisors/Committee Members: n/a (external-examiner), Dr. Hal Whitehead (graduate-coordinator), Dr. Sanotsh Lall (thesis-reader), Dr. Susan Ziegler (thesis-reader), Dr. Suzanne Budge (thesis-supervisor), Received (ethics-approval), Not Applicable (manuscripts), Not Applicable (copyright-release).
Subjects/Keywords: carbon isotope analysis; fatty acid analysis; essential fatty acids; compound-specific isotope analysis
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APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
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Manager
APA (6th Edition):
AuCoin, L. R. (2011). Fractionation of carbon isotopes during fatty acid
metabolism in Atlantic pollock (Pollachius virens). (Masters Thesis). Dalhousie University. Retrieved from http://hdl.handle.net/10222/14370
Chicago Manual of Style (16th Edition):
AuCoin, Lacey R. “Fractionation of carbon isotopes during fatty acid
metabolism in Atlantic pollock (Pollachius virens).” 2011. Masters Thesis, Dalhousie University. Accessed April 12, 2021.
http://hdl.handle.net/10222/14370.
MLA Handbook (7th Edition):
AuCoin, Lacey R. “Fractionation of carbon isotopes during fatty acid
metabolism in Atlantic pollock (Pollachius virens).” 2011. Web. 12 Apr 2021.
Vancouver:
AuCoin LR. Fractionation of carbon isotopes during fatty acid
metabolism in Atlantic pollock (Pollachius virens). [Internet] [Masters thesis]. Dalhousie University; 2011. [cited 2021 Apr 12].
Available from: http://hdl.handle.net/10222/14370.
Council of Science Editors:
AuCoin LR. Fractionation of carbon isotopes during fatty acid
metabolism in Atlantic pollock (Pollachius virens). [Masters Thesis]. Dalhousie University; 2011. Available from: http://hdl.handle.net/10222/14370
Dalhousie University
24.
Krumhansl, Kira.
Detrital Production in Kelp Beds.
Degree: PhD, Department of Biology, 2012, Dalhousie University
URL: http://hdl.handle.net/10222/14444
► Detrital subsidy from highly productive kelp beds and forests to adjacent habitats represents a major form of connectivity between coastal ecosystems that regulates regional patterns…
(more)
▼ Detrital subsidy from highly productive kelp beds and
forests to adjacent habitats represents a major form of
connectivity between coastal ecosystems that regulates regional
patterns of community organization and production. In this thesis,
I investigated environmental and biological factors that influence
the rate of detrital production in Nova Scotian kelp beds, with
emphasis on the role of invasive species in altering these
dynamics. The rate of blade erosion of the dominant kelp species
(Saccharina latissima and Laminaria digitata) increased
significantly with the level of encrustation by the invasive
bryozoan Membranipora membranacea and the extent of grazing damage
by the native snail Lacuna vincta, and by increased water
temperature and site exposure. The rate of detrital production (as
dry mass) ranged from 0.5 to 1.71 kg m-2 y-1 across 5 sites, and
increased linearly with kelp bed biomass. Spatial variation in the
total level of grazing damage on kelp blades by L. vincta was
explained in part by a negative relationship with site exposure,
and the distribution of grazing along blades was regulated by kelp
growth rate and the associated production of grazing-deterrent
polyphenolics. Grazing damage by L. vincta that exceeded 0.5 to
1.0% of blade area caused increased rates of erosion during heavy
wave action associated with a passing hurricane. The maximum stress
before breakage, toughness, and extensibility of blade tissues
decreased with the degree of encrustation by M. membranacea or
grazing damage by L. vincta, which cause degradation and removal of
the outer cell layers of kelp tissues, resulting in stress
concentration and breakage at lower force applications than
required to break undamaged tissues. The invasive green alga Codium
fragile and S. latissima differed with respect to nutritional
quality and changes in biochemical composition that occurred over
the course of degradation on a sandy bottom adjacent to a kelp bed.
Macrofaunal communities colonizing detrital deposits responded to
these differences. These findings demonstrate that invasive species
can alter the quantity and quality of detritus produced from
subtidal kelp beds, and that their community-level effects can
extend well beyond the invaded habitats via the export of
detritus.
Advisors/Committee Members: Dr. Jon Witman (external-examiner), Dr. Hal Whitehead (graduate-coordinator), Dr. Heike Lotze, Dr. Tamara Romanuk, Dr. Jon Grant (thesis-reader), Dr. Robert Scheibling (thesis-supervisor), Not Applicable (ethics-approval), Yes (manuscripts), Yes (copyright-release).
Subjects/Keywords: Kelp; detritus; connectivity; resource subsidy; invasive
species; Membranipora; Codium
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APA (6th Edition):
Krumhansl, K. (2012). Detrital Production in Kelp Beds. (Doctoral Dissertation). Dalhousie University. Retrieved from http://hdl.handle.net/10222/14444
Chicago Manual of Style (16th Edition):
Krumhansl, Kira. “Detrital Production in Kelp Beds.” 2012. Doctoral Dissertation, Dalhousie University. Accessed April 12, 2021.
http://hdl.handle.net/10222/14444.
MLA Handbook (7th Edition):
Krumhansl, Kira. “Detrital Production in Kelp Beds.” 2012. Web. 12 Apr 2021.
Vancouver:
Krumhansl K. Detrital Production in Kelp Beds. [Internet] [Doctoral dissertation]. Dalhousie University; 2012. [cited 2021 Apr 12].
Available from: http://hdl.handle.net/10222/14444.
Council of Science Editors:
Krumhansl K. Detrital Production in Kelp Beds. [Doctoral Dissertation]. Dalhousie University; 2012. Available from: http://hdl.handle.net/10222/14444
Dalhousie University
25.
Boudreau, Stephanie Anne.
EXPLAINING VARIATION IN AMERICAN LOBSTER (HOMARUS
AMERICANUS) AND SNOW CRAB (CHIONOECETES OPILIO) ABUNDANCE IN THE
NORTHWEST ATLANTIC OCEAN.
Degree: PhD, Department of Biology, 2012, Dalhousie University
URL: http://hdl.handle.net/10222/14603
► In this thesis I assessed the causes of long-term changes in two large, commercially important decapod crustacean populations, American lobster (Homarus americanus) and snow crab…
(more)
▼ In this thesis I assessed the causes of long-term
changes in two large, commercially important decapod crustacean
populations, American lobster (Homarus americanus) and snow crab
(Chionoecetes opilio), in the northwest (NW) Atlantic Ocean. By
combining available time-series data, including commercial
landings, research surveys, and local ecological knowledge (LEK), I
explored the causes of an observed ecosystem shift in the NW
Atlantic (~1950–2009) which entailed a region-wide decline of
groundfish and an increase in benthic invertebrates, including
these decapods. Three hypotheses were examined to explain the
increase in decapod abundance: (1) the predation hypothesis,
whereby a decrease in predatory groundfish led to an increase in
their decapod prey (top-down effects); (2) the climate hypothesis,
whereby changes in temperature or other climatic variables helped
to increase decapod numbers (bottom-up effects); and (3) the
anthropogenic hypothesis, whereby changes in fishing pressure drove
decapod population dynamics. I explored these hypotheses separately
for lobster and snow crab, which may experience different
ecological and commercial pressures. First, I investigated the
interactions between predatory groundfish and lobster in the
inshore region of southwest Nova Scotia. Long-term
fisheries-independent abundance indices for lobsters and their
predators are available for Gulf of Maine (GOM) waters in the USA,
but not in Canada. To address research gaps I designed and executed
a survey to collect the LEK of lobster fishermen fishing in the
Canadian GOM. Forty-two fishermen were interviewed. Corresponding
survey results from the USA were compared to the LEK results. Both
sources provided evidence for a top-down effect (predation
release), contributing to observed increases in GOM lobster
abundance and landings. Second, I explored relationships between
lobster abundance and landings in the NW Atlantic as they may
relate to temporal changes in predators, temperature, climate
(North Atlantic Oscillation Index, NAOI), and fishing. Available
landings data and fisheries-independent abundance estimates were
collated to investigate trends in lobster abundance and catch.
Links between lobster, groundfish, temperature and climate indices
were explored using mixed effects models. Results offered partial
support for the predation hypothesis, namely in the waters off
Newfoundland, Nova Scotia, and southern New England as well as
broad support for a climate effect on early life stages. This
effect appeared related to a region-wide climate signal, the NAOI,
but was independent of changes in water temperature. Fishing effort
appeared to be following lobster abundance, rather than regulating
abundance in a consistent way. Third, variation in snow crab
abundance was examined through meta-analysis of time-series data of
cod and crab abundance and temperature. Temperature had opposing
effects on the two species: snow crab abundance was negatively
correlated with temperature whereas cod and temperature were
positively related.…
Advisors/Committee Members: Richard A. Wahle (external-examiner), Hal Whitehead (graduate-coordinator), Heike K. Lotze, Sandra J. Walde, M. John Tremblay (thesis-reader), Boris Worm (thesis-supervisor), Received (ethics-approval), Yes (manuscripts), Yes (copyright-release).
Subjects/Keywords: Local ecological knowledge; American lobster; Gulf of
Maine; Ecosystem effects of fishing; Atlantic cod; Decapods;
Lobster; Crab; Trophic-cascades; Ecosystem effects; Anthropogenic
effects; Species interactions; Predation; Climate; Snow crab;
Meta-analysis; Northwest Atlantic Ocean; Top-down interactions;
Time series analysis; Fisheries; Ocean temperature
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Chicago ·
MLA ·
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CSE |
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Manager
APA (6th Edition):
Boudreau, S. A. (2012). EXPLAINING VARIATION IN AMERICAN LOBSTER (HOMARUS
AMERICANUS) AND SNOW CRAB (CHIONOECETES OPILIO) ABUNDANCE IN THE
NORTHWEST ATLANTIC OCEAN. (Doctoral Dissertation). Dalhousie University. Retrieved from http://hdl.handle.net/10222/14603
Chicago Manual of Style (16th Edition):
Boudreau, Stephanie Anne. “EXPLAINING VARIATION IN AMERICAN LOBSTER (HOMARUS
AMERICANUS) AND SNOW CRAB (CHIONOECETES OPILIO) ABUNDANCE IN THE
NORTHWEST ATLANTIC OCEAN.” 2012. Doctoral Dissertation, Dalhousie University. Accessed April 12, 2021.
http://hdl.handle.net/10222/14603.
MLA Handbook (7th Edition):
Boudreau, Stephanie Anne. “EXPLAINING VARIATION IN AMERICAN LOBSTER (HOMARUS
AMERICANUS) AND SNOW CRAB (CHIONOECETES OPILIO) ABUNDANCE IN THE
NORTHWEST ATLANTIC OCEAN.” 2012. Web. 12 Apr 2021.
Vancouver:
Boudreau SA. EXPLAINING VARIATION IN AMERICAN LOBSTER (HOMARUS
AMERICANUS) AND SNOW CRAB (CHIONOECETES OPILIO) ABUNDANCE IN THE
NORTHWEST ATLANTIC OCEAN. [Internet] [Doctoral dissertation]. Dalhousie University; 2012. [cited 2021 Apr 12].
Available from: http://hdl.handle.net/10222/14603.
Council of Science Editors:
Boudreau SA. EXPLAINING VARIATION IN AMERICAN LOBSTER (HOMARUS
AMERICANUS) AND SNOW CRAB (CHIONOECETES OPILIO) ABUNDANCE IN THE
NORTHWEST ATLANTIC OCEAN. [Doctoral Dissertation]. Dalhousie University; 2012. Available from: http://hdl.handle.net/10222/14603
Dalhousie University
26.
Demko, Alana.
Temporal and individual song variation in the Canada Warbler
(Cardellina canadensis).
Degree: MS, Department of Biology, 2012, Dalhousie University
URL: http://hdl.handle.net/10222/14610
► Song repertoire structure, organization, and use were studied in 68 male Canada Warblers (Cardellina canadensis) in a breeding population in New Hampshire in 2010-2011. On…
(more)
▼ Song repertoire structure, organization, and use were
studied in 68 male Canada Warblers (Cardellina canadensis) in a
breeding population in New Hampshire in 2010-2011. On average,
males had complex repertoires of 12 phrases and 55 variants.
Repertoire sharing was negatively related to distance between
territories, and positively related to longer territory tenure,
evidence that males learn songs from neighbours. Males used two
singing modes: (I) slow, regular delivery of less variable songs,
and (II) fast, intermittent delivery of more variable songs
interspersed with chips. Males used Mode I when unpaired and when
near females, and Mode II at dawn and during territory disputes, a
pattern similar to other warbler species with two song categories.
Detectability (whether a male sang) differed little between 1-, 3-,
5-, and 10-min count intervals. Song output and detectability were
highest at dawn and in unpaired males, and lowest in paired males
late in the season.
Advisors/Committee Members: Dr. Hal Whitehead (graduate-coordinator), Dr. Marty Leonard (thesis-reader), Dr. Leslie Phillmore (thesis-reader), Dr. Cindy Staicer (thesis-supervisor), Received (ethics-approval), No (manuscripts), No (copyright-release).
Subjects/Keywords: Canada Warbler; Cardellina canadensis; vocal behaviour;
song; Parulidae; detectability; singing modes; song sharing;
repertoire
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Chicago ·
MLA ·
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CSE |
Export
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Manager
APA (6th Edition):
Demko, A. (2012). Temporal and individual song variation in the Canada Warbler
(Cardellina canadensis). (Masters Thesis). Dalhousie University. Retrieved from http://hdl.handle.net/10222/14610
Chicago Manual of Style (16th Edition):
Demko, Alana. “Temporal and individual song variation in the Canada Warbler
(Cardellina canadensis).” 2012. Masters Thesis, Dalhousie University. Accessed April 12, 2021.
http://hdl.handle.net/10222/14610.
MLA Handbook (7th Edition):
Demko, Alana. “Temporal and individual song variation in the Canada Warbler
(Cardellina canadensis).” 2012. Web. 12 Apr 2021.
Vancouver:
Demko A. Temporal and individual song variation in the Canada Warbler
(Cardellina canadensis). [Internet] [Masters thesis]. Dalhousie University; 2012. [cited 2021 Apr 12].
Available from: http://hdl.handle.net/10222/14610.
Council of Science Editors:
Demko A. Temporal and individual song variation in the Canada Warbler
(Cardellina canadensis). [Masters Thesis]. Dalhousie University; 2012. Available from: http://hdl.handle.net/10222/14610
Dalhousie University
27.
Kozela, Christopher Paul.
ENVIRONMENT-DEPENDENT CAUSES AND CONSEQUENCES OF MUTATION IN
SACCHAROMYCES CEREVISIAE.
Degree: PhD, Department of Biology, 2012, Dalhousie University
URL: http://hdl.handle.net/10222/14821
► Environmental effects on mutation have been documented for many years but have concentrated on agents that directly interact with DNA. Mutation research in its early…
(more)
▼ Environmental effects on mutation have been documented
for many years but have concentrated on agents that directly
interact with DNA. Mutation research in its early history
investigated a variety of more mundane environmental factors at
levels that inhibited biological function and attempted to
characterize their mutagenicity. This thesis revisits these old
questions armed with more modern methods. It consists of one review
chapter and three experimental chapters. The review chapter
proposes that biological organization itself acts to direct
mutation pressure, and that many mutations are context dependent
within this organization. Experimentally, I performed an
approximately 1,500-generation mutation accumulation (MA)
experiment using the budding yeast Saccharomyces cerevisiae as an
evolutionary genetic model. This thesis investigates the rates and
distribution of effects of new mutations on fitness when they
accumulate under a moderate salt stress. The first experimental
section describes the production of the MA lines, measures the
diploid fitness traits mitotic growth rate and sporulation, and
uses changes in fitness among replicate lines to infer mutation
parameters affecting these traits. Mutation rate estimates for
these traits were roughly doubled in the salt stress treatment. The
proportion of beneficial mutations was high for mutations affecting
sporulation in both MA treatments but zero for growth rate.
Measurements of haploid viability and haploid growth rate on
strains derived from the diploid MA lines were used to infer
mutation parameters. Mutation rates affecting haploid growth were
ten-fold higher in our salt-line derivatives than those derived
from the non-stress treatment. Variance component analysis
identified a large fraction of genetic variation arising from
differences among haploids within the same tetrad. This component
was significantly larger in the salt MA treatment than the
non-stress treatment. MA lines were subjected to a novel weak-acid
stress. Mutation rate estimates were 38-fold higher in the salt MA
treatment when lines were tested under acid stress.
Cross-environmental genetic correlation for growth in acid stress
versus standard media was significantly different between the two
MA treatments suggesting that both MA environment and test
environment are important factors when considering mutational
effects on fitness.
Advisors/Committee Members: David Hall (external-examiner), Hal Whitehead (graduate-coordinator), Robert Latta (thesis-reader), Robert Lee (thesis-reader), Mark O. Johnston (thesis-supervisor), Not Applicable (ethics-approval), Not Applicable (manuscripts), Not Applicable (copyright-release).
Subjects/Keywords: Evolutionary Genetics; Mutation; Environmental Stress
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APA ·
Chicago ·
MLA ·
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CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Kozela, C. P. (2012). ENVIRONMENT-DEPENDENT CAUSES AND CONSEQUENCES OF MUTATION IN
SACCHAROMYCES CEREVISIAE. (Doctoral Dissertation). Dalhousie University. Retrieved from http://hdl.handle.net/10222/14821
Chicago Manual of Style (16th Edition):
Kozela, Christopher Paul. “ENVIRONMENT-DEPENDENT CAUSES AND CONSEQUENCES OF MUTATION IN
SACCHAROMYCES CEREVISIAE.” 2012. Doctoral Dissertation, Dalhousie University. Accessed April 12, 2021.
http://hdl.handle.net/10222/14821.
MLA Handbook (7th Edition):
Kozela, Christopher Paul. “ENVIRONMENT-DEPENDENT CAUSES AND CONSEQUENCES OF MUTATION IN
SACCHAROMYCES CEREVISIAE.” 2012. Web. 12 Apr 2021.
Vancouver:
Kozela CP. ENVIRONMENT-DEPENDENT CAUSES AND CONSEQUENCES OF MUTATION IN
SACCHAROMYCES CEREVISIAE. [Internet] [Doctoral dissertation]. Dalhousie University; 2012. [cited 2021 Apr 12].
Available from: http://hdl.handle.net/10222/14821.
Council of Science Editors:
Kozela CP. ENVIRONMENT-DEPENDENT CAUSES AND CONSEQUENCES OF MUTATION IN
SACCHAROMYCES CEREVISIAE. [Doctoral Dissertation]. Dalhousie University; 2012. Available from: http://hdl.handle.net/10222/14821
Dalhousie University
28.
Farmer, Robert Gordon.
Observer error in citizen ornithology.
Degree: PhD, Department of Biology, 2012, Dalhousie University
URL: http://hdl.handle.net/10222/15414
► Citizen science, which uses volunteer observers in research, is fast becoming standard practice in ecology. In this thesis, I begin with an essay reviewing the…
(more)
▼ Citizen science, which uses volunteer observers in
research, is fast becoming standard practice in ecology. In this
thesis, I begin with an essay reviewing the benefits and
limitations of citizen science, and then measure the influence of
several forms of observer error that might bias ornithological
citizen science. Using an internet-based survey, I first found that
observer skill level can predict the nature of false-positive
detections, where self-identified experts tend to falsely detect
more rare species and moderately-skilled observers tend to falsely
detect more common species. I also found that overconfidence is
widespread among all skill levels, and hence that observer
confidence is an unreliable indication of data quality. Using
existing North American databases, I then found that older
observers tend to detect fewer birds than younger observers –
especially if the birds' peak call frequencies exceed 6 kHz – and
that published long-term population trend estimates and
high-pitched (>= 6 kHz) peak bird vocalization frequencies are
negatively correlated. Taken together, these data suggest that both
hearing loss and other sensory changes might be negatively biasing
long-term trend estimates. In the next chapter, I measured how
observer experience can bias detection data. In solitary observers,
I found that detections tend to increase over the first 5 years of
service (e.g. learning effects), after which they decline
consistently (e.g. observer senescence). Conversely, among survey
groups that may be motivated to exceed a previous year's species
count, I found that species richness tends to increase consistently
with consecutive survey years. In this case, individual sensory
deficits may be offset by group participation. Lastly, I
re-evaluated the established assumption that the quality of new
volunteers on North American Breeding Bird Survey routes is
increasing over time. I showed that the existing measure of
“quality” ignores variable lengths of observer service, and that,
after accounting for this variable, “quality” is unchanging.
Throughout this thesis, I also show how generalized additive mixed
models can address these biases statistically. My findings offer
new opportunities to improve the accuracy and relevance of citizen
science, and by extension, the effectiveness of wildlife
conservation and management.
Advisors/Committee Members: Charles M. Francis (external-examiner), Hal Whitehead (graduate-coordinator), Marty Leonard (thesis-reader), Andy Horn (thesis-reader), Joanna Mills Flemming (thesis-reader), Marty Leonard (thesis-supervisor), Received (ethics-approval), Yes (manuscripts), Not Applicable (copyright-release).
Subjects/Keywords: long-term surveys; citizen science; observer effects; bias; detection probability; wildlife management; bioacoustics; birdsong
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APA ·
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MLA ·
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Manager
APA (6th Edition):
Farmer, R. G. (2012). Observer error in citizen ornithology. (Doctoral Dissertation). Dalhousie University. Retrieved from http://hdl.handle.net/10222/15414
Chicago Manual of Style (16th Edition):
Farmer, Robert Gordon. “Observer error in citizen ornithology.” 2012. Doctoral Dissertation, Dalhousie University. Accessed April 12, 2021.
http://hdl.handle.net/10222/15414.
MLA Handbook (7th Edition):
Farmer, Robert Gordon. “Observer error in citizen ornithology.” 2012. Web. 12 Apr 2021.
Vancouver:
Farmer RG. Observer error in citizen ornithology. [Internet] [Doctoral dissertation]. Dalhousie University; 2012. [cited 2021 Apr 12].
Available from: http://hdl.handle.net/10222/15414.
Council of Science Editors:
Farmer RG. Observer error in citizen ornithology. [Doctoral Dissertation]. Dalhousie University; 2012. Available from: http://hdl.handle.net/10222/15414
Dalhousie University
29.
Beaulieu, Gabrielle.
The Implications of Predator Management for an Endangered
Shorebird; Do Nest Exclosures Affect the Behaviour of Piping
Plovers and their Predators?.
Degree: MS, Department of Biology, 2012, Dalhousie University
URL: http://hdl.handle.net/10222/15520
► Predators are a threat to many ground-nesting shorebirds, although it remains largely unknown how they interact with passive predator management techniques such as nest exclosures.…
(more)
▼ Predators are a threat to many ground-nesting
shorebirds, although it remains largely unknown how they interact
with passive predator management techniques such as nest
exclosures. I examined the effects of nest exclosures on incubating
Piping Plovers (Charadrius melodus melodus) and their predators on
nesting beaches in Kouchibouguac and PEI National Parks. A
combination of behavioural observations, video monitoring of nests
and an artificial nest experiment was used to examine the effects
of nest exclosures in this study system. The behaviour of Piping
Plovers did not differ between exclosed and unexclosed nests,
although different types of predators seemed to have an effect on
plover nest attentiveness. Predators visited exclosed nests more
often than unexclosed nests and spent more time in the vicinity of
exclosed nests than unexclosed nests. Since increased adult
mortality and nest abandonment have been documented at exclosed
Piping Plover nests, as well as nests of other shorebirds, the
results of this study provide evidence of a link between predator
harassment and these negative effects.
Advisors/Committee Members: n/a (external-examiner), Hal Whitehead (graduate-coordinator), Leslie Phillmore, Colleen Barber and Cheri Gratto-Trevor (thesis-reader), Marty Leonard and Deborah Austin (thesis-supervisor), Not Applicable (ethics-approval), Not Applicable (manuscripts), Not Applicable (copyright-release).
Subjects/Keywords: Piping Plover; nest exclosure; predator; remote video
camera; artificial nest experiment; National Park
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APA ·
Chicago ·
MLA ·
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CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Beaulieu, G. (2012). The Implications of Predator Management for an Endangered
Shorebird; Do Nest Exclosures Affect the Behaviour of Piping
Plovers and their Predators?. (Masters Thesis). Dalhousie University. Retrieved from http://hdl.handle.net/10222/15520
Chicago Manual of Style (16th Edition):
Beaulieu, Gabrielle. “The Implications of Predator Management for an Endangered
Shorebird; Do Nest Exclosures Affect the Behaviour of Piping
Plovers and their Predators?.” 2012. Masters Thesis, Dalhousie University. Accessed April 12, 2021.
http://hdl.handle.net/10222/15520.
MLA Handbook (7th Edition):
Beaulieu, Gabrielle. “The Implications of Predator Management for an Endangered
Shorebird; Do Nest Exclosures Affect the Behaviour of Piping
Plovers and their Predators?.” 2012. Web. 12 Apr 2021.
Vancouver:
Beaulieu G. The Implications of Predator Management for an Endangered
Shorebird; Do Nest Exclosures Affect the Behaviour of Piping
Plovers and their Predators?. [Internet] [Masters thesis]. Dalhousie University; 2012. [cited 2021 Apr 12].
Available from: http://hdl.handle.net/10222/15520.
Council of Science Editors:
Beaulieu G. The Implications of Predator Management for an Endangered
Shorebird; Do Nest Exclosures Affect the Behaviour of Piping
Plovers and their Predators?. [Masters Thesis]. Dalhousie University; 2012. Available from: http://hdl.handle.net/10222/15520
Dalhousie University
30.
Johnstone, Devon.
LONG-TERM EVIDENCE THAT PRECOCIOUS PARR CAN SIGNIFICANTLY
INCREASE THE EFFECTIVE SIZE OF A POPULATION OF ATLANTIC SALMON
(SALMO SALAR).
Degree: MS, Department of Biology, 2012, Dalhousie University
URL: http://hdl.handle.net/10222/15321
► I describe temporal changes in the genetic composition of a small anadromous Atlantic salmon (Salmo salar) population from South Newfoundland, an area where salmon populations…
(more)
▼ I describe temporal changes in the genetic composition
of a small anadromous Atlantic salmon (Salmo salar) population from
South Newfoundland, an area where salmon populations are considered
as Threatened (COSEWIC 2010). I examined the genetic variability
(13 microsatellite loci) in 869 out-migrating smolt and
post-spawning kelt samples, collected from 1985 to 2011 for a total
of 22 annual collections and a 30 year span of assigned cohorts. I
estimated the annual effective number of breeders (Nb) and the
generational effective population size (Ne) through genetic methods
and demographically using the anadromous sex ratio. Comparisons
between genetic and demographic estimates show that the anadromous
spawners inadequately explain the observed Ne estimates, suggesting
that mature male parr are significantly increasing Nb and Ne over
the study period. Spawning as parr appears to be a viable and
important strategy in the near absence of anadromous
males.
Advisors/Committee Members: Daniel Heath (external-examiner), Hal Whitehead (graduate-coordinator), Jeff Hutchings (thesis-reader), Paul Bentzen (thesis-reader), Daniel Ruzzante (thesis-supervisor), Not Applicable (ethics-approval), Not Applicable (manuscripts), Not Applicable (copyright-release).
Subjects/Keywords: Atlantic salmon; microsatellite; effective population size; genetics; parr; conservation; genetic monitoring
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APA ·
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MLA ·
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CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Johnstone, D. (2012). LONG-TERM EVIDENCE THAT PRECOCIOUS PARR CAN SIGNIFICANTLY
INCREASE THE EFFECTIVE SIZE OF A POPULATION OF ATLANTIC SALMON
(SALMO SALAR). (Masters Thesis). Dalhousie University. Retrieved from http://hdl.handle.net/10222/15321
Chicago Manual of Style (16th Edition):
Johnstone, Devon. “LONG-TERM EVIDENCE THAT PRECOCIOUS PARR CAN SIGNIFICANTLY
INCREASE THE EFFECTIVE SIZE OF A POPULATION OF ATLANTIC SALMON
(SALMO SALAR).” 2012. Masters Thesis, Dalhousie University. Accessed April 12, 2021.
http://hdl.handle.net/10222/15321.
MLA Handbook (7th Edition):
Johnstone, Devon. “LONG-TERM EVIDENCE THAT PRECOCIOUS PARR CAN SIGNIFICANTLY
INCREASE THE EFFECTIVE SIZE OF A POPULATION OF ATLANTIC SALMON
(SALMO SALAR).” 2012. Web. 12 Apr 2021.
Vancouver:
Johnstone D. LONG-TERM EVIDENCE THAT PRECOCIOUS PARR CAN SIGNIFICANTLY
INCREASE THE EFFECTIVE SIZE OF A POPULATION OF ATLANTIC SALMON
(SALMO SALAR). [Internet] [Masters thesis]. Dalhousie University; 2012. [cited 2021 Apr 12].
Available from: http://hdl.handle.net/10222/15321.
Council of Science Editors:
Johnstone D. LONG-TERM EVIDENCE THAT PRECOCIOUS PARR CAN SIGNIFICANTLY
INCREASE THE EFFECTIVE SIZE OF A POPULATION OF ATLANTIC SALMON
(SALMO SALAR). [Masters Thesis]. Dalhousie University; 2012. Available from: http://hdl.handle.net/10222/15321
◁ [1] [2] [3] ▶
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Open Access Theses and Dissertations