SummaryAn effective conservation strategy for a species requires knowledge of its biology and life history. This applies to the endangered Ma’oma’o Gymnomyza samoensis, a honeyeater endemic to the Samoan archipelago. Now locally extinct in American Samoa, this species is currently found only in declining numbers on the islands of Upolu and Savai’i in Samoa. Despite being endangered, the life history and breeding behaviour of the Ma’oma’o has not been documented previously. Here we examine Ma’oma’o nesting and breeding biology, which are unique among studied honeyeaters and unusual for passerines in general. Ma’oma’o lay only a single egg per clutch and have an extended breeding season that occurs outside the rainy season and peaks during budburst. Allometric analysis of the length of the nesting period of different honeyeaters versus adult body weight showed that Ma’oma’o remain in the nest for a longer period than expected for their body size. The post-fledging dependency period of 2.5–3 months was also extended compared to other honeyeater species. No Ma’oma’o were observed re-nesting after successfully raising a chick, though pairs attempted to re-nest following breeding failure. Despite the extended breeding season, the maximum annual reproductive capacity of Ma’oma’o is limited by their one-egg clutch and failure to nest again after fledging one chick. We discuss how these slow life history traits can influence conservation strategies, affect monitoring and limit recovery.

Habitat fragmentation and invasive species are two of the greatest threats to species diversity worldwide. This is particularly relevant for oceanic islands with vulnerable endemics. Here, we examine how habitat fragmentation influences nest predation by Rattus spp. on cup-nesting birds in Samoan forests. We determined models for predicting predation rates by Rattus on artificial nests at two scales: (i) the position of the bird's nest within the landscape (e.g. proximity to mixed crop plantations, distance to forest edge); and (ii) the microhabitat in the immediate vicinity of the nest (e.g. nest height, ground cover, slope). Nest cameras showed only one mammal predator, the black rat (Rattus rattus), predating artificial nests. The optimal model predicting nest predation rates by black rats included a landscape variable, proximity to plantations and a local nest site variable, the percentage of low (<15 cm) ground cover surrounding the nest tree. Predation rates were 22 ± 13% higher for nests in forest edges near mixed crop plantations than in edges without plantations. In contrast, predation rates did not vary significantly between edge habitat where the matrix did not contain plantations, and interior forest sites (>1 km from the edge). As ground cover reduced, nest predation rates increased. Waxtags containing either coconut or peanut butter were used as a second method for assessing nest predation. The rates at which these were chewed followed patterns similar to the predation of the artificial nests. Rural development in Samoa will increase the proportion of forest edge near plantations. Our results suggest that this will increase the proportion of forest birds that experience nest predation from black rats. Further research is required to determine if rat control is needed to maintain even interior forest sites populations of predator-sensitive bird species on South Pacific islands.

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On 6 January 2004, Tropical Cyclone Heta devastated much of the South Pacific island nation of Niue. The forest suffered extensive damage, particularly to the north-western sector, with many trees uprooted and others stripped of branches and foliage. Even though some patches of forest in the southeast sustained little damage, many lupe (Pacific pigeon, Ducula pacifica) and kulukulu (purple-crowned fruit dove, Ptilinopus porphyraceus) entered eastern villages in search of food and water after the cyclone, a very unusual behavior. This paper details our findings from a survey of some of Niue's forest birds carried out during September 2004 and compares these with results from a similar survey in September 1994. Five-minute point count data, an index of conspicuousness, from three transects showed that heahea (Polynesian triller, Lalage maculosa) were more abundant in 2004 than in 1994, that the results were variable from transect to transect for miti (Polynesian starling, Aplonis tabuensis) and kulukulu, but that significantly fewer lupe were detected along all three transects in 2004 than previously. We tentatively suggest that the decline in the lupe population was caused mainly by unsustainable human hunting during 1994-2004, rather than mortality caused by the cyclone.

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