Non-breeding ecology of New Zealand falcon (Falco novaeseelandiae) in a pine plantation forest.
Degree: PhD, Zoology, 2017, Massey University
Deforestation and conversion to intensive agriculture historically caused a large
reduction in numbers of the New Zealand falcon or Kārearea (Falco novaeseelandiae),
resulting in its current classification as Nationally Vulnerable. Several studies in
plantation forests have documented the ecological benefits of limited timber
harvesting on diversities of avian species through providing habitat heterogeneity.
New Zealand falcons occur in managed plantation forests. To date, however, detailed
information regarding falcon prey abundance, habitat use, home‐range size, and
breeding behaviour has been limited to their breeding season. Little is known about
their winter use of managed forests and how forest operations affect their survival and
reproductive ability by restricting their mating system.
I investigated a falcon population living in a large plantation forest, Kaingaroa forest
through addressing the following questions: (1) how changes in forest structures
influence falcons’ habitat use and home‐range size in relation to winter prey
abundance and availability, (2) how the reduction in habitat heterogeneity by largescale
harvesting affects falcon’s home‐range size and overlap, (3) the risk of secondary
poisoning from 1080 operations and falcon annual survival, and (4) how constraints by
changes in the forest structure and compositions shape the mating system of the
Kaingaroa falcon population. I used radio‐tracking data to establish the extent and
habitat composition of winter home‐ranges, and monitoring survival of falcons before
and after 1080 poisoning operations. I used transect surveys to assess the availability
of potential prey birds, and behavioural observation to measure pair breeding
I found that falcons used the ecotone between mature‐pine stands and young‐pine
stands (the edge‐habitat) most frequently followed by their hunting ground (youngpine
stands – 0–3‐year‐old pine trees). Total prey abundance was similar across all
habitats and sizes of open fields. The dynamic changes to forest structure created by
clear‐cutting and its effect on prey accessibility are the most profound factor
influencing falcon space use. Winter home‐range sizes of forest falcons (used
Kaingaroa exclusively) were smaller than those of farmland falcons, which used
farmland > 10 % of total tracking duration. I found that falcons used smaller home
ranges when the forest provided the edge‐habitats that were concentrated among
mature‐pine stands through creating open‐patches less than 3 km2 that are distributed
closely (< 3 km apart). Results indicate that timber forests could hold a greater number
of falcons with these forest compositions. Thirty‐seven adult New Zealand falcons
were exposed to carrot bait 1080 poison during the three winter months (May–
August), and 17 adult falcons were exposed to cereal bait 1080 poison by aerial
droppings in 2013 and 2014, and all these falcons except one survived. One radiotagged
male died and although a toxicology test found not 1080 residues,…
Subjects/Keywords: New Zealand falcon;
Kaingoroa State Forest;
Research Subject Categories::NATURAL SCIENCES::Biology::Terrestrial, freshwater and marine ecology::Ethology and behavioural ecology
to Zotero / EndNote / Reference
APA (6th Edition):
Horikoshi, C. (2017). Non-breeding ecology of New Zealand falcon (Falco novaeseelandiae) in a pine plantation forest. (Doctoral Dissertation). Massey University. Retrieved from http://hdl.handle.net/10179/12292
Chicago Manual of Style (16th Edition):
Horikoshi, Chifuyu. “Non-breeding ecology of New Zealand falcon (Falco novaeseelandiae) in a pine plantation forest.” 2017. Doctoral Dissertation, Massey University. Accessed July 02, 2020.
MLA Handbook (7th Edition):
Horikoshi, Chifuyu. “Non-breeding ecology of New Zealand falcon (Falco novaeseelandiae) in a pine plantation forest.” 2017. Web. 02 Jul 2020.
Horikoshi C. Non-breeding ecology of New Zealand falcon (Falco novaeseelandiae) in a pine plantation forest. [Internet] [Doctoral dissertation]. Massey University; 2017. [cited 2020 Jul 02].
Available from: http://hdl.handle.net/10179/12292.
Council of Science Editors:
Horikoshi C. Non-breeding ecology of New Zealand falcon (Falco novaeseelandiae) in a pine plantation forest. [Doctoral Dissertation]. Massey University; 2017. Available from: http://hdl.handle.net/10179/12292