We report the 1st use of a satellite transmitter to track the endemic New Zealand falcon (Falco novaeseelandiae). The movements of an adult female bush falcon in Kaingaroa Forest east of Lake Taupo, central North Island were monitored during a 3-year period from Feb 2002. The geolocations of the falcon were mapped and revealed that the falcon remained close to her nesting territory throughout the study. The home range included an area of c. 200 km2. The falcon nested in pine compartments (0–3 years old) for 3 consecutive years; her nests averaged 5 km apart. After nightfall the falcon was located within the 95% isopleth of her home range, highlighting her sedentary nature. During the breeding season the falcon appeared to wander outside of her home range, with the furthest recorded distance from its centre being 137 km. Throughout the 3 years, observations suggest the falcon preferred to stay close to open areas, which may be related to the frequency of hunting opportunities.
Following the translocation of North Is kokako (Callaeas cinera wilsoni) to Kapiti I, southern North Is, New Zealand, Department of Conservation staff noted that most pairs were forming between individuals that came from the same source origin. This study investigated whether geographic variation in dialects influenced mate selection and, ultimately, pair formation on Kapiti I. Between Nov 1999 and Mar 2001 songs of male kokako that had paired and were resident at a single site were recorded. In addition, recordings were obtained from the Department of Conservation of birds in the source areas. Analysis of the songs indicated that kokako songs were typical of their areas of origin at the time of translocation and differed from songs of birds from different source areas. Translocated female kokako preferentially chose males whose repertoire was typical of the acoustic environment they experienced before translocation. Song analysis and pair formation of kokako born on Kapiti I indicates that the observed assortative mating was a temporary phenomenon in the years after translocation, which did not continue following juvenile recruitment.
New Zealand average atmospheric temperature showed little increase from the 1850s onwards for almost 100 years, but increased rapidly after c.1940. The increase in temperatures was accompanied, at least in parts of New Zealand, by an increase in precipitation,. We investigated the relationship between the arrival years (1st breeding) of the bird species that self-introduced to New Zealand during the 20th century and the period of turpentine increase. Because these birds come from Australia the warming might be a prerequisite to colonize New Zealand. When considering the 1st breeding years as events in a univariate point process the process is non-stationary and the rate function has its estimated maximum in 1953. This estimate may indicate that the sequence of invasions of New Zealand by additional bind species could be a response to climate changes although the coincidence is on its own not sufficient to prove that climate changes have affected the self-introduction of birds from Australia into New Zealand. Alternative and additional explanations are discussed.
The grey warbler (Gerygone igata) is the main host of the shining cuckoo (Chrysoccocyx lucidus) in New Zealand. I describe 4 observations of egg-laying by shining cuckoos in the nests of grey warblers, and 2 observations of adult cuckoos evicting, or attempting to evict, nestling warblers from non-parasitised nests. Nest were parasitised from 0658 to 1731 h NZDT, and the cuckoos took 5–18 s to lay their egg. In 3 nests in which it could be determined, the cuckoo left the nest with an egg in its bill. Warblers were present at 2 nests during parasitism and responded by attacking the cuckoo. Cuckoos evicted nestlings by pulling them out through the nest entrance and throwing them on the ground. Head- wounds on evicted chicks suggest they were pecked. Nestling eviction by adult shining cuckoos has not been previously reported and it may be a strategy to increase nest availability by inducing hosts to relay.
Gray studied the last natural mainland population of kakapo in Fiordland in the 1970s. Between 1974 and 1977 all 15 male birds located occupied home ranges high on the sides of valleys in areas of diverse vegetation associated with the tree line or avalanche and alluvial fans. Track-and-bowl systems were frequently positioned on the crests of ridges and knolls on well-drained sunny slopes. Studies of feeding sign and of faecal content using cuticle analysis provided detail of kakapo diet, confirming the bird to be an herbivore. About 80 species of plants were eaten in Fiordland. The kakapo bill is adapted to crushing and extracting nutrients and retaining fibre which is expelled as distinctive ‘chews’. A preliminary study of the nutrients in kakapo food suggested that the birds selected the most nutritious plant parts and species.