Ecological traits and conservation biology of five fossorial 'sand-swimming' snake species (Simoselaps : Elapidae) in south-western Australia

Although small, nocturnal, fossorial snakes are a significant component of the reptile fauna in many parts of the world, their biology is poorly known . An 11-year pit-trapping study in urban bushland remnants near the city of Perth, Western Australia, provided data from > 500 captures of small fosso rial snakes of the genus Simoselaps. The five species differed in relative abundances and in distribution, both among localities and among habitats wi thin a single locality. For example, three saurophagous taxa (Simoselaps be rtholdi, S. bimaculatus, S. calonotos) were most abundant in Banksia woodla nd, whereas two species that feed on reptile eggs (S. semifasciatus, S. fas ciolatus) were most abundant in coastal heath. Capture rates for most speci es were low (for three of the five species, < one specimen captured per 100 0 trapdays), and these taxa may be genuinely rare in most of the habitats t hat we surveyed. Activity patterns were highly seasonal, with little activi ty in winter or in midsummer. The two oophagous species showed a more restr icted activity period (late spring-early summer) than did species with broa der dietary habits. In the most abundant taxon (Simoselaps bertholdi), male s were active mainly during spring (the mating season) and females during a utumn, after oviposition. Capture rates and body condition of the captured snakes varied substantially among seasons and across years. Low capture rat es mean that very prolonged surveys are needed to determine reliably whethe r or not a taxon occurs on any given site.