A Report on the Status of the Herpetofauna of the Commonwealth of Dominica, West Indies

Home , Anolis cristatellus, Anolis oculatus, Leptodactylus fallax

A report on the status of the herpetofauna of the Commonwealth of Dominica, West Indies

Anita Malhotra1,3, Roger S. Thorpe1, Eric Hypolite2, Arlington James2

1 School of Biological Sciences, University of Wales Bangor, Gwynedd LL57 2UW, UK 2 Forestry, Wildlife and Parks Division, Botanic Gardens, Roseau, Commonwealth of Dominica 3 Corresponding author; e-mail: [email protected]

Abstract. We review the status of the herpetofauna of the Commonwealth of Dominica, which is often cited as having the most complete extant herpetofauna of all the Lesser Antillean islands, a region which has suffered much historical extinction. Recent years have seen a number of threats of grave concern to island and regional endemic species, the chief of these being the arrival of chytridiomycosis on this island with negative effects on the mountain chicken Leptodactylus fallax, and the establishment of a non-native Greater Antillean anole, Anolis cristatellus, which has succeeded in displacing the native endemic Anolis oculatus from a part of the island in less than a decade.

Key words: Anolis cristatellus; Anolis oculatus; chytridiomycosis; habitat loss; Iguana delicatissima; invasive species; Leptodactylus fallax; Lesser Antilles; mountain chicken.

Introduction: General Ecology of Dominica Dominica is one of the largest of the eastern Caribbean islands. However, by most standards it is a small island, being only 48 km long and 24 km at its widest point. It has a maximum altitude of 1447 m (Morne Diablotin) and several peaks over 1000 m distributed from the extreme northern to the southern tip (ﬁg. 1). It receives an extremely high rainfall (in excess of 10,000 mm on the highest peaks). The spatial and temporal variation in the distribution of rainfall determines the distribution of varying habitats on the island (Lang, 1967). Reptiles form a signiﬁcant part of its fauna, and it is one of the few Lesser Antillean islands that appears to have retained its original reptile and amphibian fauna over the last 200 years. Xerophytic (or xeric) woodland (often misleadingly referred to as dry scrub woodland) occurs in areas of low rainfall (<2000 mm) with a pronounced dry season, predominantly on the Caribbean (leeward) coast. The vegetation is char- acterised by deciduous species, which shed their leaves during the dry season (Feb- ruary to May). There are few epiphytes (except in localised areas where a moister

Figure 1. Map of Dominica, showing signiﬁcant peaks (triangles), protected areas, the three main population centres and other points of interest including those mentioned in the text (squares). The range of the invading Anolis cristatellus as of February 2006 is shown by stippling. Within this range, the native Anolis oculatus is presently absent or very rare.