We report Records Appraisal Committee (RAC) decisions regarding Unusual Bird Reports received between 1 Jan 2011 and 31 Dec 2012. Among the 137 submissions accepted by the RAC were the 1st New Zealand record of Pacific gull (Larus pacificus), the 2nd record of emperor penguin (Aptenodytes forsteri), and the 3rd & 4th records of a crane (Grus sp., unidentifiable to species). Other notable records included the 1st accepted sighting of a South Island kokako (Callaeas cinerea) since 1967, the 1st record of New Zealand dabchicks (Poliocephalus rufopectus) breeding in the South Island since 1941, and the 1st records of Snares crested penguin (Eudyptes robustus) from the Auckland Islands, sooty albatross (Phoebetria fusca) from the Chatham Islands, white-faced heron (Egretta novaehollandiae) from Antipodes Island, and Australian coot (Fulica atra) and common sandpiper (Tringa hypoleuca) from Stewart Island. In addition, notable influxes of plumed whistling ducks (Dendrocygna eytoni), great shearwaters (Puffinus gravis), Australian pelicans (Pelecanus conspicillatus), gull-billed terns (Gelochelidon nilotica) and Arctic terns (Sterna paradisaea) occurred during 2011-12.
The shore plover (Thinornis novaeseelandiae) is a highly threatened shorebird endemic to New Zealand. It is particularly susceptible to introduced mammalian predators, and has a very small total population and a very limited range. This paper lists the translocations that have formed the core of the shore plover recovery programme over the past 22 years, and summarises the outcomes. In the early 1990s, a captive population was established in mainland New Zealand using birds reared from eggs transferred from the last self-sustaining wild population on the Chatham Islands. Since 1994, captive-bred birds have been released on 5 offshore islands around the New Zealand mainland in attempts to found new populations. There have also been transfers of wild-bred birds from South East I to Mangere I in the Chatham Is. Between 1994 and April 2012, 404 juvenile and 28 adult shore plover have been released at a total of 6 sites. Birds bred at 4 of the 6 sites, and breeding populations established at 3 of them. However, recent mammalian predator incursions at 1 (and probably 2) of those, and habitat limitation at the 3rd, mean that the translocated populations are all currently small (6 pairs or less), and their long-term future is uncertain. Other challenges faced during the programme include avian predation of released birds, high rates of dispersal, and outbreaks of avian pox. In spite of recent setbacks, the risk of extinction for the species has gradually been reduced. Since 1990, a self-sustaining captive population has been set up, the number of breeding pairs has increased, and the number of breeding populations in the wild has risen from 2 to 4 (although 1 is currently facing extirpation). Features of the shore plover programme that have contributed to these outcomes are outlined. Aspects of shore plover ecology revealed by the translocations are noted. While progress has been made, existing populations will need to grow, and further populations will need to be established before the shore plover’s threat ranking improves.
Bone samples from 2 surviving populations of New Zealand’s endemic and endangered brown teal (Anas chlorotis) had a much smaller distribution of stable isotopic values (δ13C, δ15N) than those from Holocene-age fossil bones of the same species. Comparison with δ13C and δ15N values from 2 other taxa of known ecologies indicated that some brown teal were forest floor omnivores. The results indicate that the riparian and estuarine wetlands occupied by present natural populations represent only an extreme, truncated part of the species’ potential habitat. To aid present conservation efforts we suggest that brown teal be released into forested areas and islands managed as mammal-free enclaves to test whether modern birds can survive in habitats once occupied by now-extirpated populations. Palaeoecological studies, including stable isotope analyses, can be used to identify conservation options not obvious from research on declining remnant populations in anthropogenic environments.
A number of studies have found that birds in urban areas alter singing behaviour, possibly to increase signal transmission and avoid masking by high levels of anthropogenic background noise. However, few studies have focused on how these song differences might be interpreted by receivers. We investigated differences in song between populations of urban and rural Australian magpies (Gymnorhina tibicen), an Australian species abundant in both habitats. First, we compared urban and rural magpie songs to determine if magpies shift the frequency, duration and output of songs in response to anthropogenic noise. Unlike some songbirds, urban magpies did not shift minimum frequencies to avoid masking, however they did sing shorter songs. We then played back unfamiliar urban and rural songs to groups of both urban and rural magpies, and monitored their territorial responses. Results showed that differences in song across both habitats do not affect receiver responses, indicating that magpies from both urban and rural habitats can readily communicate with each other. Interestingly, rural magpies responded with more aggression to rural songs than to either urban songs or to control songs. We propose that the flexibility of Australian magpie songs aids this species in its ability to adapt successfully to urban environments.
A unique Pterodroma petrel shot at sea near the Antipodes Islands in 1926 has features intermediate between white-headed petrel (Pterodroma lessonii) and soft-plumaged petrel (Pt. mollis). Its mitochondrial DNA indicates that its mother was a Pt. mollis and we conclude that it is a hybrid. We theorise that Pt. mollis had begun colonising Antipodes Island by the 1920s and some pairing with the locally abundant congeneric Pt. lessonii occurred. Hybridisation in Procellariiformes is rare worldwide but several cases have now been reported from the New Zealand region.
Transfers of North Island robin (Petroica longipes) and North Island tomtit (P. macrocephala toitoi) were undertaken from various sites around the Wellington region to within the mammal-proof fence at the Zealandia-Karori Sanctuary from 2001-2004. Differing methodologies were trialled to test translocation protocols for these species. Robin translocations (34 males and 42 females from Kapiti I translocated in 2000 and 2001) were straightforward and robins established in the sanctuary despite the fence not being a physical barrier to dispersal. They bred from the first season and numbers have since increased rapidly. Tomtits were transferred from 2 source populations (Kapiti I and Akatarawas; 39 males and 12 females over 4 years from 2001-2004) but failed to establish. To hold tomtits in an aviary and avoid aggression it was necessary to keep sexes apart. Although successful tomtit breeding was observed both within and outside the sanctuary, predation pressure was higher outside the sanctuary. A progressive move of tomtit territories out of the sanctuary may have been a response to increasing aggression from the expanding robin population.
Information was collected from a small population of peafowl living in Mansion House Historic Reserve, Kawau Island, from 1995 to 2010. Peacocks used an exploded lek breeding system, and displayed at areas where human and natural foods occurred. Mating took place between late Sep and mid Dec. Breeding was successful in the presence of a substantial North Island weka (Gallirallus australis greyi) population. An average of 1.4 (SE = 0.6, n = 10) young were fledged per successful clutch. In the winter of 2004, all peahens disappeared and the population thereafter comprised only males. Despite the absence of females, peacocks continued to display for 5 years after all peahens were lost. The breeding biology of this introduced population appears to be similar to that in their native range.
A total of 3,455 southern black-backed gull (Larus dominicanus dominicanus) chicks were banded at 4 Canterbury localities between 1959 and 1993: Ashley River 1,239; Waimakariri River 219; Motunau Island 1,997. Only 180 (5.2%) of these chicks were recovered, 3.0% of the river colony chicks and 6.9% of the Motunau Island chicks. Three-quarters of recoveries were in rural environments with most others on the coast; 14 had been shot or trapped and killed. The oldest recovery from the river colonies was 6.1 years old but this may be an underestimate due to wear and loss of aluminium bands used early in the study period; Motunau Island birds were found up to 25.7 years after banding. Birds dispersed widely from the Wairarapa to Southland travelling up to 486 km. Recoveries of first year birds off-colony averaged 96 km which is more than the older birds, 54 km; 7/10 birds that travelled over 200 km were first year birds. On average, Motunau Island birds were found further from the natal colony than birds from the river colonies. My results indicate that dispersal distances and direction of black-backed gulls are variable, and that dispersal can occur between the North and South Islands.
We conducted counts of spotted shags (Stictocarbo punctatus) at Matiu/Somes and Mokopuna islands in Wellington Harbour quarterly during the period from 2002-05 and sporadically at these sites and at Makaro/Ward Island during 2007 -12. This population is important as it is one of the few North Island breeding areas, and one of only 2 in the Wellington region. Shag numbers appear to have been stable or possibly declining during this period, with fluctuations between both months and years. An average of 210 individuals was noted during 12 comprehensive counts, with a maximum of 354 spotted shags in 2004. Breeding occurred during late winter and spring in 2010 and 2012. We recommend ongoing monitoring of this population as an important population at a New Zealand level, which is accessible and easily counted from a boat.
In New Zealand, translocation of native species is increasingly being proposed and carried out by community groups as well as the Department of Conservation (DOC). Usually a formal translocation proposal needs to be prepared and approved. Trends in the number and type of proposals approved during 2002-2010 are discussed. Over 300 translocation proposals were approved in this period. Many proposals consisted of more than one transfer. In 2002, proposals from community groups and joint proposals with DOC made up 16% of the approved proposals. In 2005 this had increased to 58%, but it dropped down to 38% in 2007 and in 2010 it had again increased to 71%. Proposals to move birds made up the largest proportion of applications (74%), followed by reptiles (15%), plants (6%) and invertebrates (5%). Kiwi (Apteryx spp.), robin (Petroica spp.), North Island kokako (Callaeas wilsoni) and seabird species (including Procellariformes, Spheniscidae and Laridae) were the most commonly translocated species. In response to the increased number of applications from community groups to carry out translocations, DOC has revised and improved the process for carrying out native species translocation projects.
We present the first detailed data on the Great Barrier Island (GBI) sub-population of the northern New Zealand dotterel (NNZD; Charadrius obscurus aquilonius). The breeding season population has averaged 48 birds (range: 41– 64) since 2000. At Awana on GBI, productivity has averaged >1.0 fledged chick per pair-year. The apparent survivorship of adult birds was less than that in the North Auckland sub-population. After breeding, most GBI birds congregated at Whangapoua Estuary/Okiwi Spit in the north of the island, making this a site of international importance under the Ramsar Convention (1971). The post-breeding population of c.56 birds (range: 41 – 77) was augmented by local juveniles and input from elsewhere. Banding returns provided evidence of movement between GBI and the adjacent mainland sub-population on the Coromandel Peninsula. There was no evidence that fewer predatory mammal species on GBI benefits the species at present. Conservation emphasis should focus on controlling mammalian predators and managing human impacts at breeding sites, especially early in the breeding season.
Pipit (Anthus novaeseelandiae) numbers and distribution were assessed at 7 sites near Whangarei, Northland. Foot surveys located significantly more pipits than car surveys at my study site on Ormiston Road. Car-based surveys identified Ormiston Road as a pipit site 88% of the time in summer, and other subsequent car surveys recorded pipits at rates of 0.06 – 0.07 birds/km on Whangarei roads. Calling and breeding behaviours commenced in August but no fledged young were seen before January. Monitored pairs fledged between 0 and 1 young per pair between 1999-00 and 2002-03. Pipits were generally recorded during the breeding season at densities of less than 1.6 birds/km, but up to 16.7 birds/km post breeding.
Reliable techniques need to be developed for monitoring the distribution and abundance of the endangered Australasian bittern (matuku, Botaurus poiciloptilus). We trialed 2 complementary methods for estimating the number of booming Australasian bitterns: acoustic triangulation from fixed listening stations, and using kayaks to quietly approach booming birds. Trials were conducted over 2 booming seasons (2011 and 2012) at Hatuma Lake, Hawkes Bay. The 2 methods gave similar estimates of the number of bitterns using Hatuma Lake (2011: 8-9 bitterns by triangulation and 9-10 bitterns by close approaches; 2012: 8-9 bitterns using triangulation and 7-8 bitterns by close approaches). We recommend using close approaches because there appeared to be less count-error or a combination of the 2 methods to estimate numbers of Australasian bitterns on small wetlands (
The Chatham Islands tui (Prosthemadera novaeseelandiae chathamensis) is a large forest honeyeater with a threat ranking of nationally endangered. It is restricted to a single population commuting between Pitt and South East Islands, with an estimated global population of 260 adults. We carried out a translocation of 54 juvenile tui from South East Island (42 females, 12 males) to the Awatotara Valley, Chatham Island in March 2009 (14 birds) and February 2010 (40 birds). Tui were held captive in an aviary for 2-8 days on the source island, and 3-6 days at the release site. Tui lost weight in captivity prior to transfer, but birds held for longer periods recouped more weight than those held briefly. Post-release survival was high; all birds from the 2009 cohort survived their first winter to breed at the release site. Survival of the 2010 cohort was less (54%), but this may have been due to our reduced ability to detect birds following wider dispersal. This translocation was part of a community project and has seen unprecedented support from the Chatham Island community and is a major step forward in the development of community driven conservation in the Chatham Islands.