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Records of all mollymawk sightings on Bollons Island, Antipodes Islands, are reviewed. Data are provided to confirm the breeding record for Black-browed Mollymawk Diomedea melanophrys melanophrys and add a new breeding record for the NZ White-capped (Shy) Mollymawk Diomedea cauta steadi.

When interpreting counts of forest birds it is seldom possible to distinguish the effects of changing density from those of changing conspicuousness; these often arise from the birds’ singing and calling. To investigate this, birds first seen were recorded separately from those first heard when counting birds in forest of the Orongorongo Valley, Wellington, New Zealand. Apparent changes in the frequency of Paradise Duck (Tadorna variegata) in the river valley, and of the Song Thrush (Turdus philomelos), Whitehead (Mohoua albicilla), Grey Warbler (Gerygone igata) and Chaffinch (Fringilla coelebs) in the forest coincided with changes in the frequency of their singing or calling; they were considered suspect. Changes in the frequency of the Black-backed Gull (Larus dominicanus) on the riverbed, and of N.Z. Pigeon (Hemiphaga novaeseelandiae), Blackbird (Turdus merula), Fantail (Rhipidura fuliginosa), Silvereye (Zosterops lateralis), Bellbird (Anthornis melanura), Tui (Prosthemadera novaeseelandiae), and Australian Magpie (Gymnorhina tibicen) did not show a similar correlation. Special study of the ways in which birds either advertise or conceal themselves is needed. Correction factors may never compensate completely for the effects of the birds’ varying conspicuousness.

Captive Weka (Gallirallus australis) were offered two species of native frogs (Leiopelma hochstetteri and L. archeyi) as prey. The anti-predator behaviour and/or gland secretions of the frogs were sufficient to avoid damage and allow them to escape. The leaf litter habitats where frogs occur in the Coromandel Ranges are least likely to be favoured by Weka. Objects under which frogs were found were heavier than those generally moved by Weka while foraging. Weka seem to constitute less of a risk to frogs than earlier believed.

We studied Cape Pigeons Daption capense at The Snares, one of its northern most breeding sites, from pre-laying to fledging during 1985/86 and 1986/87, and compared our data with those from other localities. At The Snares, mean laying dates were 10 November 1985 and 8 November 1986, mean hatching date was 25 December 1985, mean fledging date was 14 February 1986, breeding success was 58.7% in 1985/86 and 50.0% in 1986/87, and adult male annual survival was 94%. Laying mainly begins later at higher latitude breeding sites and there are differences in pre-laying colony attendance between some populations. Incubation and nestling periods are similar throughout the species’ range suggesting an inherent rather than environmentally-induced explanation for the relatively short nesting season of fulmars compared to other petrels.

During 1994, participants in the Beach Patrol Scheme patrolled 3253 km of the New Zealand coastline. 5477 dead seabirds of 55 species, plus 121 individuals of 25 non- seabird species were found. Unusual finds were the first New Zealand record of a Newell’s Shearwater (Puffinus newelli), one Soft-plumaged Petrel (Pterodroma mollis) and one Eastern Little Tern (Sterna albifrons sinensis). Large numbers of Kerguelen Petrels (Lugensa brevirostris), Flesh-footed Shearwaters (Puffinus carneipes) and Buller’s Mollymawks (Diomedea bulleri) were beach-cast in 1994. Fisheries-related mortality was identified for some seabirds found on beach patrols.

The Saddleback (Philesturnus carunculatus) is now confined to New Zealand offshore islands free of the introduced carnivorous mammals, i.e. rats, feral cats and mustelids, which are assumed to have exterminated the species on the mainland during the last century. The North Island Saddleback (Philesturnus carunculatus rufusater) coexists with the Polynesian rat (Rattus exulans) while the South Island Saddleback (P c. carunculatus) thrives only on rat-free islands. An experimental transfer to Kapiti island, where Norway (R. norvegicus) and Polynesian rats occur, provided an opportunity to test the hypothesis that North Island Saddlebacks could coexist with both rat species. I compared the survival of Saddlebacks on Kapiti Island wlth that on Cuvier and Little Barrier Islands where the only rodent is R. exulans. On Kapiti Island, Saddlebacks suffered high mortality, and despite high productivity, there was insufficient recruitment of young to balance losses of adults. Significantly more nests sited less than one metre above the ground were preyed on by rats on Kapiti Island than on Cuvier and Little Barrier Islands. Saddlebacks on Kapiti Island which roosted in high or secure cavities survived longer than those birds which roosted in low or vulnerable places. These observations are consistent with the ground-foraging and predatory behaviour of R. norvegicus. On Kapiti Island, 21 rat-killed birds were found at nests and roosts, whereas no rat-killed birds were found at nests and roosts on Cuvier and Little Barrier Islands, although the contents of some nests were preyed on by R. exulans. On Kapiti Island, R. norvegicus faeces were found with the remains of several dead birds, providing direct evidence that this rat was the predator. The poor survival and recruitment of Saddlebacks on Kapiti Island, coupled with observations of rat-killed birds and plundered nests near the ground, suggest that Saddlebacks are unable to coexist with both rat species, and that R. norvegicus is probably an important predator. The cavity nesting and roosting habits of the Saddleback make this species especially vulnerable to mammalian predators.

In October-November 1992 the island of Mangaia, Cook Islands, was surveyed for Tanga’eo (Halcyon tuta ruficollaris). The Tanga’eo was found to be primarily a forest bird, preferring continuous forest canopy. Its abundance was influenced by forest type, extent, and degree of habitat modification. A number of potential threats to the survival of Tanga’eo were identified including habitat loss and disturbance by Common Mynas (Acridotheres tristis). A brief survey of rodents was carried out. Although the Tanga’eo population was estimated to have been between 250 and 450 birds, low numbers of birds in apparently suitable forest in the southwest of Mangaia indicate that further research is needed to determine population trends and conservation requirements.