Asad, S., A. Wilting, J. Siku & M.-O. Rödel

Possible spatial separation at macro-habitat scales between two congeneric Psammodynastes species, including observations of fishing behaviour in Psammodynastes pictus. pp. 411-415.

Abstract. Separation at spatio-temporal scales can permit the co-existence of morphologically similar species within the same habitat. Furthermore, competition for food resources in the same environment can lead to separation via specialised hunting strategies. Here, we analysed micro (perch sites) and macro (habitat use) scale data for two co-occurring, con-generic snake species, Psammodynastes pictus and Psammodynastes pulverulentus, to delineate patterns of separation. Additionally, we present an observation of a successful fishing event, and two possible instances of fishing behaviour in P. pictus. Although our dataset was limited (n = 38), we found significant separation in proximity to streams and stream size between both species. Psammodynastes pictus was found within closer proximity to water than P. pulverulentus, with P. pictus preferring wider deeper streams than P. pulverulentus. This data, along with the observed fishing event, suggests that P. pictus is more associated with aquatic habitats and their resources than P. pulverulentus. This may allow the two species to occupy different niches in the same habitat without competition. 

Key words. Squamata, Serpentes, Pseudaspididae, Psammodynastes, fishing, ambush behaviour, habitat-separation.