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.