| Citation |
BirdLife International 2019. Hydrornis gurneyi . The IUCN Red List of Threatened Species 2019: e.T22698628A157110021. https://dx.doi.org/10.2305/IUCN.UK.2019-3.RLTS.T22698628A157110021.en. Downloaded on 12 February 2020. |
Description |
JUSTIFICATION
Gurney
s Pitta is evaluated as Critically Endangered as the current very rapid estimated rate decline in the population is projected to increase further over the following 13 years due to the lack of legal protection of the remaining small areas of flat, lowland forest suitable for the species. There is a high risk of rapid conversion of virtually all remaining habitat to plantations, which could plausibly take place over just a few years.
RANGE DESCRIPTION
Pitta gurneyi is now restricted to few remaining areas of lowland forest in Tenasserim, Myanmar, following what appears to be its extinction within adjacent peninsular Thailand. The species was only discovered in Myanmar in 2003, when it was found at four sites with a maximum of 10-12 pairs at one location (BirdLife International 2003, Eames et al. 2005). It was found to be not uncommon at some sites, and on the basis of previously reported population densities and extent of suitable habitat, the population was estimated to number 5,152-8,586 pairs (Eames et al. 2005). In 2007-2008, the species was recorded at 101 census points in Myanmar (Donald et al. 2009). Since 1999, an estimated 81% of the available intact lowland flat forest within the range has been lost, primarily through conversion to plantations for palm oil or rubber. The extent of remaining suitable habitat was estimated at 656 km2 in 2015 (Lay Win et al. 2015). In tandem with this habitat loss, 2016 surveys revisiting 141 points where the species had been recorded between 2003 and 2012 found that it remained only at 41 of these sites (Shwe et al. 2018.).
Historically it was apparently common in Thailand, but there were no field observations in Thailand between 1952 and 1986 (BirdLife International 2001). Since 1986, intensive surveys found it in at least five localities, although it disappeared from all but one of these, Khao Nor Chuchi, in the late 1990s. This population has declined from 44-45 pairs in 1986 to just nine pairs in 1997, most of which are outside protected-area boundaries. Detailed work in 2003-2007 recorded birds at 27 sites in Khao Nor Chuchi, and a further survey of the area in 2009 found 12 individuals responding to tape playback (Anon. 2009, Donald et al. 2009). Intensive surveys of the site in 2015 and 2016 recorded no individuals, until a single female was recorded in April 2016 (P. Insua-Cao in litt. 2016). The outlook for the population in Thailand is regarded as bleak (J. Eames in litt. 2012, P. Round in litt. 2012, Round 2014): the species is thought to be functionally extinct in the country (Round 2014, P. Insua-Cao in litt. 2016).
DESCRIPTION
In Myanmar, on the basis of previously reported population densities and extent of suitable habitat, the population was estimated in 2004 to be 5,152-8,586 pairs, equating to 10,300-17,100 mature individuals, or roughly 15,000-26,000 individuals in total. More recently it has become evident that the species has suffered very rapid declines and the population in 2019 is much lower, and is now believed to be fewer than 2,500 mature individuals and may be even fewer, although there has not been an attempt to update the population estimate using the same methodology (C. Zöckler in litt. 2015, Lay Win et al. 2015, T. D. W. Aung in litt. 2016). As such, the population is currently placed in the band 1,000-2,500 mature individuals.
Trend Justification: A very rapid decline has been estimated over the past three generations from a repeat survey of almost all presence sites, owing to very high rates of deforestation. This population decline is expected to become extremely rapid over the next ten years on the basis of the expected rate of deforestation in Myanmar, following uncertainty over the future status of the protected areas that are the last refuge for the population.
HABITAT AND ECOLOGY
It occurs in a range of forest habitats (Donald et al. 2014) including primary and secondary, regenerating, lowland semi-evergreen and bamboo forest, usually below 160 m (although with records up to 259 m [Donald et al. 2014]) in flat areas with slopes less than ten degrees, with an understorey containing Salacca palms, in which it nests. Recent research suggests the species uses different habitat types in Thailand and Myanmar, which is encouraging for habitat restoration work (Donald 2008). Territories are centered on gulley systems where moist conditions prevail year-round, usually with access to water, and often close to forest edge. It is likely to show "a heavy reliance on earthworms", in line with other members of the genus. It breeds during the wet season, between April and October.
THREATS
The key reason for its decline has been the almost total clearance of lowland forest in southern Myanmar and peninsular Thailand through clear-felling for timber, unofficial logging and conversion to croplands, fruit orchards, coffee, rubber and oil-palm plantations. Conversion of flat forest to oil-palm plantation in Myanmar is ongoing in southern Tenasserim with large concessions including significant tracts of Lenya Reserve Forest (P. Insua-Cao in litt. 2016; see also Donald et al. 2015). An added complication is that future deforestation rates will also be strongly influenced by internal politics in the region and the strength of the insurgency groups (P. Donald in litt. 2007). A concerning recent development is the removal of the status of Proposed National Park for Lenya Reserve Forest (T. D. W. Aung in litt. 2019), indicating that the hope that this will become a strictly protected area is unwarranted.
In Thailand at least, snare-line trapping for the cage-bird trade was also a serious threat, and there are reports of targeted trapping in Myanmar to supply demand from Thailand (P. Insua-Cao in litt. 2016). Predation by cat snakes (Boiga spp.) appears to limit reproductive success in Thailand. These predators are native, but may be present at a higher-than-natural density, having been favoured by habitat fragmentation in the area (Donald et al. 2009).
CONSERVATION ACTIONS
Conservation Actions Underway
CITES Appendix I. In Myanmar there is an ongoing project aimed at conserving remaining lowland forest in southern Tenasserim commenced in 2013, led by Fauna & Flora International with plans to designate Lenya National Park and its proposed extension, which together cover most of the Gurney Pitta’s habitat. In addition the project is seeking to engage major plantation concession holders within the landscape (P. Insua-Cao in litt. 2016).Much effort was exerted in Thailand following its rediscovery in Thailand, which quantified the population by 1989, designated Khao Nor Chuchi as first a Non-Hunting Area in 1987, then a Wildlife Sanctuary in 1993. However, economic incentives continued to govern land-use decisions, and despite a comprehensive series of projects the population continued to decline (Round 2014). The process and key tree species for habitat restoration are understood and have been tested around Khao Nor Chuchi (Elliott et al. 2008), and a tree nursery was created (Anon. 2009). A species recovery plan was produced for Thailand in 2002; and an updated plan is under development focusing on captive breeding of individuals from Myanmar for reintroduction.
Conservation Actions Proposed
Monitor population trends through regular surveys at known sites. Monitor rates of habitat loss and degradation within the speciess known range. Monitor levels of trapping. Effectively protect Lenya National Park and its extension as a matter of urgency. Strengthen law enforcement at the Thai-Myanmar border crossing to mitigate against illegal logging and the trade in caged birds (P. Insua-Cao in litt. 2016). Engage with plantation concession holders in Myanmar to set aside habitat and allow forest corridors to link habitat (P. Insua-Cao in litt. 2016). Establish an in situ protection unit with direct responsibility for safeguarding all remaining habitat, to facilitate cooperation with sanctuary officials and strengthen management and community participation. Restore forest at Khao Nor Chuchi and establish habitat corridors as first steps towards a captive breeding programme to reintroduce a viable population to Thailand (P. Insua-Cao in litt. 2016). |
