[First paragraph…] Occurring on both Auckland and Campbell Is. (52°32.4’S, 169°8.7’E; 11,300 ha), the Auckland Is pipit (Anthus novaeseelandiae aucklandicus G.R. Gray) is a subspecies of the New Zealand pipit, Anthus novaeseelandiae novaeseelandiae Gmelin (Turbott 1990). At Campbell Is, the pipit is restricted to small offshore islets. A similarly restricted distribution of this southern subspecies to offshore stacks at Campbell Is is reported by Heather & Robertson (1996), and Foggo (1984) who suggested that this situation is caused by the effects of Norway rat (Rattus norvegicus) and cat (Felis silvestris catus) predation. Foggo (1984) noted that the inability of pipits to co-exist with rats on subantarctic islands has been demonstrated in South Georgia by Pye & Bonner (1980). Foggo & Meurk (1981) commented that it is likely that rats and cats have eliminated this species from the main island. Deliberate burning of vegetation as a farming practice in the early 19th century (Wilmshurst et al. 2004) may also have restricted the distribution of the pipit. Foggo (1984) collected pipits on Dent Is in 1975 and reported that they “were immediately obvious and very tame” during a brief helicopter visit to the summit of Jacquemart Is in 1980 (Foggo & Meurk 1981), adding that on each of these offshore islands the birds had fulvous plumage. Thompson et al. (2005) encountered pipits at 2 locations on Campbell Is in 2003 and that they were distributed more extensively in 2004, 2 main centres being around Penguin Bay in the southwest, and towards the south around Eboulé Peak.
Forbes’ parakeet (Cyanoramphus forbesi) is an endangered taxon now endemic to Mangere I and Little Mangere I in the Chatham Is group, 500 km east of New Zealand. This taxon exists now as a single mixed population consisting of Forbes’ parakeets, Chatham I red-crowned parakeets (C. novaezelandiae chathamensis) and their hybrids (Taylor 1975; Nixon 1982; Chan et al. 2006). Increased attention on the conservation of Forbes’ parakeets followed from the presentation of allozyme and mitochondrial DNA control region genetic evidence which suggested that Forbes’ parakeet should be elevated from a subspecies of yellow-crowned parakeet (C. auriceps forbesi) to full species status (Triggs & Daugherty 1996; Boon et al. 2000).
[First paragraphs …] The ‘sandspit’ on the True Right bank of the Manawatu River, in Foxton Beach Village, (175°14’E 40°30’S) is a significant roosting site for migratory and resident waders, gulls, terns, pied stilts (Himantopus himantopus), royal spoonbills (Platalea regia), shags, ducks, and other birds. The ‘sandspit’ is 2-5 ha, depending on the state of the tide, c.1 km from the Tasman Sea, It is surrounded on 3 sides by the main course of the river and by tidal flats, and as well as this natural isolation, it is protected as a “bird sanctuary” by local bye-laws.
On 14 Jan 2006, I observed a flock of 29 wrybills (Anarhynchus frontalis) arrive on the ‘sandspit’, rest briefly, then take flight again and leave the area. The weather was sunny and warm, with a light south-easterly wind, and visibility was good. The tide was rising, being about mid-tide when the birds arrived. The wrybill flock arrived at c.0930 in a compact group and landed on dry sand above high water mark c.20 m in front of my position on the western edge of the ‘sandspit’. The birds settled quickly after landing and, with a few exceptions, they scarcely moved but remained close together,with c.½ of the birds resting on 1 leg. However, the birds in the flock were sufficiently separated to be counted easily using 9 × 25 binoculars. No birds attempted to feed and the flock was silent when resting. The flock rested slightly apart from the numerous lesser knots (Calidris canutus), variable oystercatchers (Haematopus unicolor), bar-tailed godwits (Limosa lapponica), pied stilts (Himantopus himantopus), and several Pacific golden plovers (Pluvialis fulva) that were also roosting on the sandspit. After about 10 min, the wrybills departed, with a few calling as they took flight. The flock quickly gained height to 10–25 m and headed south-west along the river towards the sea, returning the way they had come.
We collected and collated more than 2400 records of the rock wren Xenicus gilviventris, covering the period 1912-2005. These records allowed past and present distribution patterns to be mapped and compared. Areas from which birds have apparently disappeared were identified. The rock wren was common once on mountain ranges along or close to the Southern Alps, South Island, New Zealand, but have been recorded less frequently in many areas after 1980. More numerous records from some areas and during some decades could have resulted from differences in search effort and from inconsistency in record keeping. Nevertheless, there were consistent anecdotal accounts of decline, evidence of predation by stoats and mice, unsuccessful searches in previous strongholds and the recent extinction of 5 confamilial species indicate that the rock wren should be regarded as a threatened species.
Symbols were corrupted in the captions of several figures; captions with the correct symbols are reproduced below…
The timing and breeding success of starlings (Sturnus vulgaris) in nest boxes was monitored simultaneously at 5 localities representing northern, central, and southern New Zealand. The northern locality, (Kaikohe, 35° 25’S) was monitored for 2 consecutive years; the others, of which Winton (46° 10’S) was the southernmost, for 4 consecutive years. The median date for the laying of Oct clutches was always earlier at Winton except in 1978 when it was 4 Oct at both Kaikohe and Winton. In any 1 year the size of Oct clutches (4.43 pooled over all years and localities) and the number of young in successful broods was always greater at Winton than elsewhere. In both 1977 and 1978 the difference in laying dates between Ohau and Waikanae (only 27 km apart) was greater than between Kaikohe and Winton at opposite ends of the country. The 5 localities showed no consistent trend, one with another, in their respective median laying dates from 1 year to another. The mortality of chicks was highest at Kaikohe, except for Belmont in 1978 when the 65% mortality was attributed to stoats (Mustela erminea). The laying of 2nd clutches has a very weak genetic basis and is probably a response to environmental factors.
The Campbell Is snipe (Coenocorypha undescribed sp.) was unknown to science until its discovery on 19 ha Jacquemart I in 1997. Following the successful eradication of Norway rats (Rattus norvegicus) from 11,268 ha Campbell I in 2001, there was increasing evidence that snipe had begun to recolonise the main island: footprints were found at Monument Harbour in 2003, and a fully-feathered dependent chick was captured nearby in Mar 2005. A survey of Campbell Is snipe recolonising Campbell I was undertaken by the authors and a trained bird-locater dog during 7-15 Jan 2006. We confirmed the presence of snipe and their successful breeding at 2 sites: the outlet to Six Foot Lake (head of Monument Harbour), and near the mouth of Kirk Stream at the head of Six Foot Lake. We estimated at least 22 adult snipe to be present. Twelve adult snipe were caught, along with 5 dependent chicks with estimated ages ranging from 8 to 37 d. One snipe nest was found. Subsequent sightings in Feb 2006 revealed at least 2 snipe to be present on the north-western shores of Perseverance Harbour, c. 3 km north of where we recorded them. We document the successful re-establishment of snipe on Campbell I within 5 years of rat eradication, and recommend that their natural recolonisation be left to continue unaided.
Seasonal changes in home range size and habitat selection of kakapo (Strigops habroptilus) were investigated on Maud Island. Kakapo were radio-tracked at night in each of the four seasons between December 2000 and October 2001. Home ranges were estimated for four adult males, three juvenile males and two juvenile females in each season and for nine females in summer, each based on 20 radio-fixes per season. Home range size varied from 1.8 to 145.0 ha using the minimum convex polygon method. Home ranges were smallest in winter. Habitat selection was determined by overlaying the kakapo locations and home ranges on a vegetation map of the island. For each season selection ratios were calculated for each vegetation community. Pine plantation (Pinus radiata) was selected for in summer, whereas the treeland community dominated by five-finger (Pseudopanax arboreus) was selected for in the autumn. Dense pole stands of manuka (Leptospemum scoparium) and pasture communities were avoided by kakapo.
We studied the New Zealand morepork (Ninox novaeseelandiae) over 2 breeding seasons on Mokoia I, Lake Rotorua, North Island, New Zealand. Ten pairs were monitored in the 1995/96 breeding season and 8 in the 1996/97 season. Nest sites included tree cavities, hollows amongst tree fern fronds, nest boxes provided for saddleback (Philesturnus carunculatus) and scrapes on the ground. Nest cavities were 0-5.2 m agl. Clutch size was 1-3 eggs; egg dimensions averaged 39.0 mm × 32.9 mm. The incubation period for 1 clutch was at least 24 days. Only females were observed to incubate eggs and brood nestlings; males roosted nearby. Two chicks were weighed and measured throughout their development and the nestling period was determined for 1 chick. Nestling development is described. Breeding success was lower in the year after a poisoning operation to eradicate mice from the island. Juvenile mortality was high after fledging. The dispersal of 3 juveniles was monitored, and females appeared to move earlier and disperse farther than males.
The context of modern conservation management of kakapo is introduced and a brief overview of the research presented in this special issue of Notornis is provided.
182 bird taxa have been recorded from the Chatham Is archipelago, including 32 reported here that are additional to the most recently published reviews in 1990 and 1994. Nine of these new records are from subfossil bone deposits; the remaining 23 are new records of vagrants or colonists, although 2 result from taxonomic revision of albatross species, where it is not clear how many terminal taxa had been recorded before 1994. Antipodean albatross (Diomedea antipodensis), Salvin’s mollymawk (Thalassarche salvini), and Indian yellow-nosed mollymawk (T. carteri) were recorded breeding on the Chatham Is for the 1st time since 1994, with the latter being the 1st breeding record for the New Zealand region. Notable among the list of over 100 vagrant species recorded from the Chatham Is are the only New Zealand records to date of Atlantic yellow-nosed mollymawk (T. chlororhynchos), and willie wagtail (Rhipidura leucophrys).
The reproduction of kakapo (Strigops habroptilus) on offshore island refuges was monitored between 1990 and 2002. Productivity was primarily determined by the proportion of females that nested each breeding year. Within the same island, the proportion of females nesting each breeding year ranged between 33 – 95% but, as a proportion of the total female population, was just 5 – 42% between 1990 and 1999. The deliberate placement of the entire adult female population on Codfish Island (Whenua Hou) in anticipation of an exceptional fruit crop resulted in 95% of them nesting in 2002, raising 24 fledglings and increasing the total population by 39%. Although efforts to increase the frequency of kakapo breeding by providing supplementary food have been unsuccessful, nesting and fledging success increased significantly following the introduction of new, more intensive, management methods in 1995. Hatching success has, however, remained poor, with just 42% of eggs hatching. Comparison with related parrot species suggests that the kakapo’s hatching success is unusually low, perhaps because of inbreeding. Despite infrequent breeding and poor hatching success, the kakapo population has increased by 69% from 51 birds in 1995 to 86 in 2002. The female population has increased from 21 birds in 1995 to 41 in 2002, 20 of which are presently less than 10 years old.
Since the last review of kakapo biology, published 50 years ago, much has been learnt as a result of the transfer of all known individuals to offshore islands, and their intensive management to increase adult survival and productivity. This review summarises information on a diversity of topics, including taxonomy, plumage, moult, mass, anatomy, physiology, reasons for decline in distribution, present numbers and status, sex ratio, habitat, home range, foraging activities, diet, voice, breeding biology, nesting success, sexual maturity, and adult survival. In addition, those kakapo attributes that compromise its long-term survival in present-day New Zealand are discussed, along with management practises developed to overcome these problems.
Colony attendance and behaviour of non-breeding Buller’s albatrosses (Thalassarche bulleri) were studied at 2 Snares Is colonies in 2000-2004. Non-breeders comprised 31-32% of birds ashore in Mar-May (incubation to early chick-rearing), 44% in Jul (late chick-rearing), and 51% overall. Among non-breeders, the proportion of adults that had been recorded breeding in previous years decreased from 47% in Mar to 4% in Jul, with prebreeders (known-age birds that had not been observed breeding) dominating the composition overall (80%). The percentage of surviving birds seen ashore was 59% among prebreeders aged 6 years (modal age of first return), 88% among experienced prebreeders (birds that had been recorded ashore in >1 breeding season), 86% among remating (widowed or divorced) adults, and 63% among sabbatical (birds that had been recorded breeding in previous years, but were not breeding in the year of observation) adults. Colony attendance period was shortest among inexperienced prebreeders (latest birds to arrive), longest among 3rd year (i.e. known-age birds recorded ashore for the 3rd year) prebreeders (early arrival, late departure), and intermediate among last-time prebreeders and former breeders (early arrival, departure in mid-season). Failed breeders attended for up to 3 months, but departed after May irrespective of failure date. Birds stayed ashore for longer and at sea for shorter periods as they gained experience; the percentage of days ashore increased up to the 3rd prebreeding year, and was higher in males than females. Movements between colonies and subcolonies were most frequent during the first 3 prebreeding years. Prebreeders frequently joined display groups during their first 2 years (34% of observations in May), and associated with a nest site in May-Jul of their 3rd year. Among remating adults, displaying was most frequent in females and early in the season (Mar); their behaviour converged towards that of paired adults by May. Attendance patterns and behaviour were broadly similar to those of other albatrosses, except for earlier departure during the last prebreeding year not previously reported in an annually breeding species.
Sixteen of 26 hand-reared kakapo chicks (62%) have been successfully returned to the wild. These chicks were initially kept in thermostatically-controlled brooders, then in plastic tubs in an air-conditioned room, and finally a pen in an unheated room prior to transfer to an outdoor pen and release in the wild. Brooding temperature was progressively reduced to simulate the progressively longer period kakapo chicks spend in the nest without brooding. Humidity was maintained at 80% to simulate that measured in kakapo nests. Some chicks fed a relatively high fat diet within their first 20 days after hatching developed fatty liver disease; subsequently, chicks less than 45 days of age were fed a lower fat diet and older chicks gradually converted to a higher fat diet. Normal gut flora was successfully established in chicks by adding small quantities of adult kakapo faeces that had been screened for diseases and parasites. The growth rate of hand-reared chicks was significantly slower than that of parent-reared chicks during the first 40 days after hatching but there was no significant difference in growth rate in older chicks. Half the disparity in the growth rates of hand-reared and parent-reared chicks was due to the fact that most hand-reared chicks were suffering from ill health or injury before being taken into captivity. Two male chicks reared in isolation from other kakapo display varying degrees of sexual attraction to humans. The only sexually mature hand-reared female chick has mated and hatched a chick in the wild. Hand-reared kakapo comprised 40% of all chicks fledged since 1990 and presently comprise 20% of the total population of 86 birds.