Are saltflats suitable supplementary nesting habitats for Malaysian Plovers Charadrius peronii threatened by beach habitat loss in Thailand?

Abstract

Resort development and coastal beach erosion have led to declines in beach breeding habitat for the near-threatened Malaysian Plover (Charadrius peronii) in the Gulf of Thailand. Semi-natural saltflats may provide supplementary nesting areas. We compared the environmental conditions, incubation behaviour and nesting success of plovers breeding on sandy beaches and saltflats in Thailand. In total we monitored 21 and nine nesting attempts in 2004 (beaches and saltflats, respectively) and 26 and 22 nesting attempts in 2005. Despite higher air temperatures in the saltflats (P < 0.0001), we detected no significant differences in nest attendance (P = 0.542 and P = 0.885 for 2004 and 2005, respectively), number of incubator changes between parents (P = 0.776 and P = 0.823) or number of parental nest departures (P = 0.087 and P = 0.712) during 120 incubation observations on 55 nests. There was also no difference in hatching success between beaches in 2004 (beach = 0.65, saltflat = 0.55; P = 0.692, n = 26) and 2005 (beach = 0.46, saltflat = 0.35; P = 0.539, n = 41). These results suggest that saltflats may provide nesting habitat for Malaysian Plovers and could help enhance overall hatching success rates by reducing nesting densities on beaches. Although there are few remaining intact saltflats in coastal Thailand, there are currently vast areas of abandoned tiger prawn aquaculture ponds that could be rehabilitated into saltflats at relatively low cost. Given the large area of disused aquaculture ponds throughout Thailand and South-East Asia and the substantial human pressure on coastal habitats, there could be considerable conservation benefits to the restoration of aquaculture ponds.