Suchergebnisse

We examined the impact of habitat degradation (removal of surface rocks) on an
endangered snake species (Hoplocephalus bungaroides,
Elapidae) at 23 sites in south-eastern Australia, by quantifying the impact of
rock removal on (i) the availability of suitable shelter-sites for the snakes
and their major prey species (the velvet gecko,
Oedura lesueurii), and (ii) the numbers of snakes and
geckos. Our survey showed that both the snakes and the geckos prefer rocks
lying on other rocks, rather than on soil, and select rocks of particular
sizes. The rocks removed by bush-rock collectors overlap considerably in size
(diameter and thickness) and substrate (rock on rock) with those used by
broad-headed snakes and velvet geckos. Multivariate path analysis suggests
that population densities of broad-headed snakes (as measured by capture
rates) may be determined primarily by gecko numbers, which in turn depend upon
availability of suitable rocks. In some sites, rock numbers were substantially
reduced by anthropogenic disturbance. Thus, our survey data suggest that
bush-rock removal has contributed to the endangerment of
H. bungaroides.