Priority contribution. The rediscovery of Gurney's Pitta Pitta gurneyi in Myanmar and an estimate of its population size based on remaining forest cover

Abstract

A preliminary survey for Gurney's Pitta Pitta gurneyi was undertaken at five sites within the species' historical range in the Tanintharyi (Tenasserim) Division of Myanmar from 14 to 24 May 2003. During the surveys, Gurney's Pittas were heard and/or observed at four sites with a maximum of 10–12 pairs recorded at one site. Birds were encountered in logged primary and secondary forest below 100 m on flat ground, sometimes less than 10 m from forest edge. All encounters were within 2 km of the main trans-Tanintharyi highway. Landsat satellite imagery was used to map remaining lowland forests and Gurney's Pitta habitat in the Tanintharyi Division. Our analysis demonstrated that only 4,705 km2 of lowland forest remain with about 3,496 km2 in flat areas with slopes < 10°. On the basis of previously reported population densities, these habitats may support a population of 5,152–8,586 pairs. Much of the remaining habitat is restricted to small and fragmented patches < 1 km2 in area. The five largest patches have a total area of 1,431 km2 and range in size from 137 to 467 km2. This survey demonstrated that Gurney's Pitta still occurs within its historical range in Myanmar, although probably not at any of the historical collecting localities visited. The global population of Gurney's Pitta is at least 100% greater than the latest published estimate. This survey has also shown that the Gurney's Pitta population in southern Tanintharyi Division is under pressure from forest conversion to oil palm. Contrary to the situation in neighbouring Thailand, sufficient forest remains to establish landscape level protected areas covering a broad ecological continuum. Securing populations of Gurney's Pitta within either expanded or entirely new protected areas must be the best chance for the species and the Sundaic flora and fauna of which it is part.

The distribution and conservation of Gurney’s Pitta Pitta gurneyi in Myanmar

“…It is associated primarily with lowland Sundaic forest and appears to be able to survive, or even benefit from, a degree of forest disturbance (Round and Brockelman 1998, Donald et al 2009). While the future of the tiny population in southern Thailand remains precarious, surveys of southern Myanmar in 2003, 2007 and 2008 suggested that the species is relatively widespread and not uncommon in lowland Sundaic forests, although rapid forest loss in parts of the region means that the species’ future there is far from secure (Eames et al 2005, Donald et al 2009). These surveys suggested that the species occurs at higher altitudes and latitudes than previously suggested (Collar et al 1986, Round 1995, Collar et al 2001), with no evidence of a decline in occurrence probability up to the maximum visited altitude of 226 m asl (Donald et al 2009).…”

When is an “Extinct” Species Really Extinct? Gauging the Search Efforts for Hawaiian Forest Birds and the Ivory-Billed Woodpecker

“…The Bermuda Petrel (Petrodroma cahow) was considered extinct by 1621, but a small breeding colony was discovered in 1951 (Murphy and Mowbray 1951). Gurney's Pitta (Pitta gurneyi) in Myanmar (Eames et al 2005), a freshwater pearl mussel (Margaritifera margaritifera) in Portugal (Reis 2003), the Cherry-throated Tanager (Nemosia rourei) in Brazil (Bauer et al 2000), Bulmer's fruit bat (Aproteles bulmerae) in Papua New Guinea (Flannery 1994), Wollemi pine (Wollemia nobilis) in Australia (Woodford 2002)-all were thought to be extinct for decades or known only from fossil remains until rediscovered in recent years. In fact, the phenomenon of prematurely declaring species extinct is common enough to have been christened "Romeo's error" (Collar 1998) and the "Lazarus effect" (Keith and Burgman 2004).…”

First Record of the Spiny Turtle (Heosemys spinosa) in Myanmar

“…Coastal Tanintharyi Region is characterized by low human population densities and extensive mangrove forests (Eames et al 2005;Giesen et al 2006). Although most land near villages and towns is devoted to rice agriculture, extensive seasonally inundated wetlands remain in the floodplains of rivers that originate along the Thai-Myanmar border and flow into the Andaman Sea.…”

“…Although most land near villages and towns is devoted to rice agriculture, extensive seasonally inundated wetlands remain in the floodplains of rivers that originate along the Thai-Myanmar border and flow into the Andaman Sea. Widespread deforestation is underway in many areas of Tanintharyi Region as a result of government policies that encourage conversion of natural forest to oil palm (Elaeis guineensis) plantations (Eames et al 2005).…”

“…By far the greatest threat to H. spinosa is the widespread conversion of natural forest to oil palm plantations currently underway throughout much of southern Myanmar. Government plans called for the conversion of 231,500 ha of natural forest to oil palm plantations by 2008 (Eames et al 2005), although whether or not this goal has been attained remains unclear. Nonetheless, our own observations indicate that land clearance continues unabated, even within areas of nominally protected land such as reserved forests (Platt et al 2012).…”