a b s t r a c tBiodiversity declines in Southeast Asia have led to predictions that many vertebrate species will become extinct within 50 years. Examples of quantified deterioration in species status remain scarce, however. The Southeast Asian geographical range of the Endangered Green peafowl is still contracting due to hunting pressure and habitat disturbance. In Vietnam, the main population lies in the southcentral region with a relatively high density reported in 1998. The aim of this study was to assess the species' current status in Yok Don and Cat Tien National Parks, which are thought to contain the most important Vietnamese populations. We used line and point transects to investigate the density and analyze habitat selection and effects of human activity. The Yok Don population has decreased sharply during the past 15 years, while in Cat Tien, the estimated density was higher. Animals were most numerous close to water sources and lowest where cattle numbers were highest and ground vegetation cover absent. Here we document a significant negative population change in a previously widespread vertebrate species. Although comparisons of population data over long periods are rare, we demonstrate that taking advantage of opportunities to resurvey species can quantify population declines.

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SummaryThe endangered Green Peafowl Pavo muticus is one of the most threatened vertebrate species in South-East Asia and has undergone a rapid decline in both distribution and population density. The remaining populations are mostly limited to protected areas where an understanding of their ecological requirements is required to ensure that conservation management is effective. To clarify this, we investigated their population status and ecological requirements in Huai Kha Khaeng Wildlife Sanctuary, western Thailand. Line transect surveys across five sections of the Sanctuary revealed variation in population density, apparently linked to recent levels of human activity and management. Comparison of encounter rates along transects with those recorded in similar surveys conducted 21 years previously showed an increase in numbers in most of the peripheral areas of the sanctuary whilst numbers in the core area have remained stable. Using camera trapping and radio tracking to investigate habitat selection all year round, our results showed that the Green Peafowl preferred areas with an open understorey but a high percentage cover of ground vegetation. During the breeding season they preferred to cluster near streams to establish a display site, whilst in the non-breeding season they ranged more widely but still preferred areas of open understorey and high ground cover. We present some evidence of temporary avoidance of areas recently frequented by large predators (tiger and common leopard). Our results suggest that increased patrols to control hunting help to allow Green Peafowl populations to recover. We suggest that measures that allow recovery of populations of species such as Green Peafowl will ultimately enhance large predator conservation through increasing their prey base.

The remaining large patches of lowland forest in Tanintharyi, southern Myanmar, are the last global stronghold for the Endangered Gurney's pitta Hydrornis gurneyi. Except for a few individuals, the remaining population is now restricted to this forest, below 150 m altitude, mostly within the Nga Wun, Lenya, and Parchan Reserved Forests. However, as in much of South-east Asia, Tanintharyi has been subjected to extensive deforestation, particularly for oil palm cultivation. The aim of this research was to determine the extent of remaining habitat suitable for Gurney's pitta. During January–October 2016 we revisited 142 locations (of 147) where the species was detected during 2003–2012, and found it in only 41 of those locations (29%); in all other locations the forest had been cleared. We measured the decline of suitable habitat since 1999 by examining all available intact forest in areas with elevations < 150 m and slope < 10 °. In less than 2 decades suitable habitat has declined from 3,225 to 656 km2 (80%). Protection of remaining lowland forest is now critical. Although the expansion of oil palm cultivation has slowed since its peak in the early 2000s, two national parks proposed by the Myanmar government in 2002, which would potentially offer legal protection for most of the remaining Gurney's pitta habitat, remain on hold because of political uncertainties. We recommend an alternative conservation approach for this species, based on an Indigenous Community Conserved Area model, and further research to improve knowledge of the species and to determine how it could be saved from extinction.

The green peafowl Pavo muticus is a highly threatened galliform species that was historically distributed widely across South-east Asia. Evidence shows a recent population decline and range contraction for this species, linked with habitat degradation and over-exploitation. This study aimed to determine the current known distribution across mainland South-east Asia and investigate potential habitat that could host remaining viable populations and contribute to the long-term survival of the species. We used locations from historical and recent records and habitat variables from a geographical information system database to model the probability of occurrence and classify key localities according to their relative importance for the species. Our results showed that the green peafowl probably occurs in less than % of its historical range across mainland South-east Asia and that remaining locations are fragmented. Four confirmed and two potential stronghold populations were identified for the species, based on the localities with high capacity to contribute to its long-term survival in large contiguous patches. These were in central Myanmar, western and northern Thailand, eastern Cambodia/south-central Viet Nam and northern Cambodia/southern Lao. Threats vary amongst countries, with continued habitat loss and degradation in many areas and hunting particularly acute in Viet Nam, Cambodia and Lao. Most of the remaining populations are in protected areas but the protection level varies widely. We propose conservation actions for each stronghold population, in accordance with the nature of the threats and protection level in each area, to prevent the local extinction of this species.