This paper describes the activity of garden, bush and riverine birds in the western Hutt hills, 1981-92. The area is 15 km north of Wellington, 7 km north of the Hutt River estuary, and 15 km south of Pauatahanui Inlet, Porirua Harbour, on the southwest coast of the North Island. Observation is based on 35 years’ residence and >12 500 10-min counts conducted between 1981 and 1992. Species first seen each day are distinguished from those first heard. Whenever possible the birds’ food was recorded. The western hills have fewer native passerines than similar habitat on the eastern hills. Several species increased or decreased during the study. Some apparent decline was attributed to the author’s hearing loss. Wind reduced bird detection. Nectar of New Zealand flax (Phormium spp.) was eaten by silvereyes (Zosterops lateralis), tui (Prosthemadera novaeseelandiae) and starlings (Sturnus vulgaris) at different times. In the study area there were about 0.9 cats (Felis catus) per household, a potential predator on birds.
We investigated the use of call count surveys to monitor weka numbers for management purposes. A Generalised Linear Model based on data from 111 nights of listening for weka at Rakauroa (North Island, New Zealand) showed that the number of calls recorded was influenced by listening site and month, but not by wind direction, wind strength, cloud cover, phase of the moon, rainfall or temperature. Mean number of calls heard was highest between December and March, with a peak in January. More birds were heard from certain listening sites. Although there was no correlation between any of the environmental variables and weka calling, wind, and rain may have reduced the audibility of weka in other studies. The estimated probability of detecting weka was 60-80% (mean = 728). At least 3 nights at each listening station were necessary to improve the census accuracy. Call counts of weka at Rakauroa between 1993 and 1997 showed a decline in the number of weka.
The total population of North Island weka (Gallirallus australis greyi) is about 4150 adults spread over five islands, one North Island population, and a number of captive birds in aviaries and mainland island programmes. Between 77% and 84% of the adult weka population are on Kawau Island. Density changes in the Mansion House Historic Reserve, and anecdotal records suggest that adult weka populations on Kawau Island has fluctuated between c.2100 and c.5000 during 1992-1999. The largest declines occurred within 12 months of the 1990-91 and 1997-98 droughts.
A captive-breeding programme was begun in August 1991 to breed North Island weka (Gallirallus australis greyi) for release at a North Island site. A total of 101 weka were released between October 1992 and January 1996 at Karangahake Gorge, southern Coromandel. The project was abandoned in March 1996 after dogs and ferrets (Mustela furo) killed many of the birds.
Rhys Philip Buckingham (MNZM) Member of the New Zealand Order of Merit, For Services to Ecology. David Edgar Crockett Companion of the Queen’s Service Order, For Public Services.
The South Island saddleback (Philesturnus carunculatus carunculatus) is one of two subspecies of the New Zealand saddleback. Despite the endangered status of this subspecies, it was not studied in detail until 1994, when 26 birds were released onto Motuara Island in the Marlborough Sounds of New Zealand. I report the foraging behaviour and diet of this reintroduced population during the first breeding season after release. South Island saddlebacks used their bills in a variety of ways when foraging, and were predominantly insectivorous. They obtained most food from the ground and five-finger (Pseudopanax arboreus), and the number of prey captured generally reflected the amount of time saddlebacks spent on foraging substrates. North and South Island saddlebacks are very similar in terms of foraging behaviour, prey handling techniques and types of invertebrate prey consumed. The foraging patterns and diet of South Island saddlebacks on Motuara Island differed from all potential competitors. I conclude that the success of the South Island saddleback transfer to Motuara Island should not be threatened by a lack of food or foraging opportunities.