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    Non-breeding ecology of New Zealand falcon (Falco novaeseelandiae) in a pine plantation forest : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Zoology at Massey University, Manawatu, New Zealand
    (Massey University, 2017) Horikoshi, Chifuyu
    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 activities. 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, however, the possibility of 1080 secondary poisoning was not entirely cleared. The survival rate of adult Kaingaroa falcons was 80% and that of juveniles was 29%. All divorces (40%) were initiated by females leaving their territories regardless of reproductive outcomes, while males exhibited greater mate and site fidelity. A high rate of extra‐pair interaction occurred by females (71%) but was absent in males. Female’s extra‐pair interaction implemented as their strategy for securing breeding opportunities. In contrast, the mate‐guarding strategy may be the most effective male’s mating strategy in the Kaingaroa falcon population. Male’s vigilant personality likely enhanced mateguarding performance. Home‐range overlap was greater in pairs that retained partners than pairs that divorced. Winter courtship displays were used for pair formation (the process of establishing a social bond) rather than pair bonding (the process of maintaining a social bond), and also used for intra‐sexual competition over females. A rapid rotation of habitat quality and sufficient prey availability in the area may shape falcons’ various mating systems. A further long‐term continual monitoring that includes the juvenile falcons is required to measure the effects of 1080 poison on the Kaingaroa falcon population. A welldesigned harvesting regime could enable the timber industry to contribute importantly to the conservation of this threatened New Zealand raptor.
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    An investigation of causes of disease among wild and captive New Zealand falcons (Falco novaeseelandiae), Australasian harriers (Circus approximans) and moreporks (Ninox novaseelandiae) : a thesis presented in partial fulfilment of the requirements for the degree of Master of Veterinary Science at Massey University, Turitea, Palmerston North, New Zealand
    (Massey University, 2014) Mirza, Vaseem
    Infectious disease can play a role in the population dynamics of wildlife species. The introduction of exotic birds and mammals into New Zealand has led to the introduction of novel diseases into the New Zealand avifauna such as avian malaria and toxoplasmosis. However the role of disease in New Zealand’s raptor population has not been widely reported. This study aims at investigating the presence and prevalence of disease among wild and captive New Zealand falcons (Falco novaeseelandiae), Australasian harrier (Circus approximans) and moreporks (Ninox novaeseelandiae). A retrospective study of post-­‐mortem databases (the Huia database and the Massey University post-­‐mortem database) undertaken to determine the major causes of mortality in New Zealand’s raptors between 1990 and 2014 revealed that trauma and infectious agents were the most frequently encountered causes of death in these birds. However, except for a single case report of serratospiculosis in a New Zealand falcon observed by Green et al in 2006, no other infectious agents have been reported among the country’s raptors to date in the peer reviewed literature. During the review of post-­‐mortem records, organisms like Mycobacterium avium, Serratospiculum sp, Sarcocystis spp, Trichomonas galllinae and several unidentified helminths were identified as contributing or definite causes of mortality in all three species of raptors. But neither Plasmodium spp nor Toxoplasma gondii infections have been demonstrated in these birds so far. Therefore, a separate study was designed to determine the presence of these pathogens in New Zealand falcon, Australasian harrier and morepork tissues, using established molecular techniques. Molecular analysis of archived New Zealand raptor tissues confirmed the presence of both Plasmodium spp (10/117; 8.5%) and T. gondii (9/117; 7.7%) in all three species of raptors. Plasmodium strains identified were P. elongatum GRW6, P. sp AFTRU5, and P. relictum GRW4 and SGS1. Surprisingly, two Australasian harriers and one morepork tested for the presence of both Plasmodium spp and T. gondii as concomitant infections. However, it is unknown whether any of the positive tested birds suffered from clinical infections, since post-­‐mortem records had no record of clinical signs of disease associated with either infections in these birds. Once the presence of the aforementioned pathogens among New Zealand raptors was established, an attempt was made to investigate their presence among live raptor populations as well. Blood samples were collected from raptors being admitted to Wildbase Hospital, Massey University, Palmerston North and Wingspan-­‐ Birds of Prey Research Centre, Rotorua. Molecular analysis of these samples by PCR did not reveal the presence of Plasmodium spp in any of the ii tested birds, but one New Zealand falcon, Australasian harrier and morepork each tested positive for the presence of T. gondii. Interestingly, none of the positive birds showed any signs of clinical illness that may be associated with toxoplasmosis in raptors. We also analysed faecal samples and throat swabs from these birds to determine the presence of pathogens like Caryospora spp, Serratospiculum spp, Salmonella spp and T. gallinae, since many of these organisms have been detected in New Zealand and are also found affecting raptors in other parts of the world. However, apart from eggs resembling Capillaria spp, none of the other pathogens listed above were identified. My study has some limitations such as a small sample size and a geographic bias in terms of birds being submitted to Massey University, Palmerston North for post-­‐mortem analysis. But this research may be regarded as the first report of Plasmodium spp and T. gondii infections among New Zealand’s three well-­‐known raptor species and further research is required to determine the prevalence of these pathogens among the country’s total raptor population, pathogenicity of the organisms towards them and the role of these birds in the epidemiology of these diseases within New Zealand
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    Spatial partitioning of morphological and genetic variation in the New Zealand falcon (Falco novaeseelandiae) : a thesis presented in partial fulfilment of the requirements for the degree of Master of Science in Conservation Biology, Massey University, Palmerston North
    (Massey University, 2014) Olley, Lena
    The New Zealand falcon (Falco novaeseelandiae) is a medium sized falcon endemic to New Zealand. New Zealand falcons have a flexible ecology, inhabiting a variety of habitats including bush, coastlines, mountains, open tussock land, farm land and exotic pine forests. Phylogenetic analysis suggests the New Zealand falcon is not sister to or related closely to any species in either Australia or South America as proposed in earlier research. Neither does it appear to fit within in any other major group such as the heirofalcons or the kestrels. The New Zealand falcon is currently defined as a single variable species with three recognised morphs or races that are referred to as the Bush, Eastern and Southern these appear to differ in colour and size. This proposal was established in 1977 and has since become generally accepted. However, there are alternative hypotheses as to how this variation is size may be spatially partitioned across the New Zealand landscape. A reassessment of the morphometric data in New Zealand falcons is needed to identify how this morphological variance is distributed. Specifically, to identify any evidence for three distinct morphs, in contrast to the alternative hypothesis of a gradient in size consistent with Bergmann’s rule. The analysis suggests that there is little support for the occurrence of three morphs of New Zealand falcon; instead, there is a distinct difference in size between the North and South Islands. There is some evidence of a gradual change corresponding to latitude but this appears to be minimal. Mean wing lengths are significantly longer in male and female falcons in the South Island compared to those in the North Island. To understand if the size difference between the North and South Islands is an effect of an adaptive response and to examine the extent of gene flow occurring between the two islands a study of neutral genetic markers is needed. Evidence of genetic structure was tested for among New Zealand falcon populations using nuclear and mitochondrial data. Little support for any population structuring was identified. Evidence from this analysis suggests that the falcons are responding to particular environmental conditions within each island resulting in a change in size, however high juvenile dispersal may be preventing the partitioning of gene flow between the North and South Islands.
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    The behaviour and development of New Zealand falcons (Falco novaeseelandiae) nesting in a plantation forest : a thesis presented in partial fulfillment of the requirements for the degree of Master of Science in Conservation Biology at Massey University, Palmerston North, New Zealand
    (Massey University, 2008) Thomas, Andrew Christopher Wyllie
    Information on the breeding behaviour and development of wild New Zealand falcons (Falco novaeseelandiae) is scarce. It has recently been shown that the species frequently uses plantation forests for breeding purposes and a better understanding of falcons breeding behaviour has implications for forestry harvesting practices as well as strategies to conserve the species. In this study the breeding behaviour and development of New Zealand falcons were recorded at two nests in Kaingaroa Forest, an extensive plantation forest, using direct hide observations. Both nests were observed during the later part of incubation, the entire nestling and early post-fledging periods. Nest observations were recorded during a four-month period between 5 November 2006 and 2 March 2007. Incubation was shared between parents and it was observed that the male provided about 30% of the total time on the eggs. The male‟s investment during the incubation period was primarily incubation of the eggs to allow the female time to hunt. Incubation remained constant after the laying of the last egg in the clutch despite a stoat (Mustela erminea) attempting to predate the eggs. During incubation, the male provided only occasional prey for the female. Brooding was also shared by both parents. The male, however, contributed only 10% of the total brooding time, mostly during the first seven days of the nestling period. Brooding activity was high for up to the first six days, before gradually declining until the chicks reached 14 days old at which point it ceased. This decline in brooding coincided with the chicks‟ development of thermo-regulation. The mean prey delivery rate was 0.82 prey items per hour and the mean feeding rate was slightly higher at 0.90 feeds per hour. Assisted feeding of the chicks was almost always undertaken by the female. The male‟s primary role during the nestling period was prey delivery. During the early nestling period the female spent the majority of the time brooding chicks. As the nestling period progressed, however, this role shifted primarily to hunting for the young. By establishing a set of guidelines for forest managers and captive breeders, this study makes a strong direct contribution to the management and conservation of the New Zealand falcon. This study establishes development milestones for breeding events, including the duration of the breeding cycle that will assist forestry managers to minimise their impact upon nesting birds.
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    An application of satellite tracking technologies to conserve wildlife : a case study approach : a dissertation presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Natural Resource Management at Massey University, Palmerston North, New Zealand
    (Massey University, 2010) Thomas, Bindi; Thomas, Bindi
    Wildlife management is an important area of conservation and has become a priority for many countries and organisations around the world. One of the fundamental components of a sound wildlife management plan is a good understanding of a species’ behaviour and habitat. For animals within inaccessible environments, satellite tracking provides a powerful tool for revealing information on animal movements and their habitat requirements. In this dissertation, the conservation benefits and technical effectiveness of satellite tracking are examined through four case studies representing a diverse range of threatened species studied for periods between six months and five years. The studies revealed important ecological insights on the in situ movement and behaviour of the African elephant (Loxodonta africana), Kruger National Park, South Africa; the New Zealand bush falcon (Falco novaeseelandiae), Central North Island, New Zealand; the estuarine crocodile (Crocodylus porosus), Darwin, Australia; and the northern royal albatross (Diomedea sanfordi), Taiaroa Head, New Zealand and Chile. For each of these studies, satellite telemetry provided location data enabling analyses of the animals’ movements and home ranges, and these analyses inform specific management recommendations. For example, the long time series study on African elephants highlighted the importance of developing reciprocal animal management policies where cross-boundary movements of animals occurred between adjacent parks. The strengths and weaknesses of different satellite tracking systems are compared and guidelines developed to assist wildlife managers in selecting the best technology to suit their research needs. An assessment of the trade-offs between the technical features built into transmitters and the associated cost is also presented. The study shows how the use of satellite tracking systems provides conservation agencies with a better understanding of wildlife behaviour and strengthens their ability to improve wildlife management planning.
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    The ecological requirements of the New Zealand falcon (Falco novaseelandiae) in plantation forestry : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Zoology at Massey University, Palmerston North, New Zealand
    (Massey University, 2007) Seaton, Richard
    Commercial pine plantations made up of exotic tree species are increasingly recognised as habitats that can contribute significantly to the conservation of indigenous biodiversity in New Zealand. Encouraging this biodiversity by employing sympathetic forestry management techniques not only offers benefits for indigenous flora and fauna but can also be economically advantageous for the forestry industry. The New Zealand falcon (Falco novaeseelandiae) or Karearea, is a threatened species, endemic to the islands of New Zealand, that has recently been discovered breeding in pine plantations. This research determines the ecological requirements of New Zealand falcons in this habitat, enabling recommendations for sympathetic forestry management to be made. Plantation forests that create a mosaic of pine stand ages across a plantation, offer suitable habitat for breeding New Zealand falcons by providing abundant nest sites, promoting high abundances of avian prey and creating favourable conditions for hunting. The diet of falcons within pine forests consisted primarily of birds, of which the majority were exotic passerines. Prey abundances were highest along pine stand edges. Both sexes preferentially hunted along pine stand edges between stands less than four years old and stands more than 20 years old. Pairs also preferentially nested along these borders, particularly within and along the edges of pine stands less than two years old. Within pine stands, nest sites were always located on the ground. Introduced predators and some forestry operations negatively affected breeding success. Nevertheless, productivity was higher than recorded for other habitats and female falcons were recorded successfully breeding in their first year for the first time. High prey densities and availabilities are suggested as the primary explanation for this. The extent of juvenile dispersal strongly suggests that pine plantations supplement populations in surrounding areas where falcons are in decline. This research demonstrates that changes to the existing forestry operational practices can influence the success of the breeding population. This research establishes that if commercial pine plantations are suitably managed, they can support extremely high falcon densities. Plantation forests therefore have a significant role to play in the future conservation of this species.