endangered species

Endemic biota of native grasslands commonly co-exist with introduced grazing mammals, and often this is seen as a conservation threat. The endangered pygmy bluetongue lizard (Tiliqua adelaidensis) is restricted to remnants of native grassland in the mid-north of South Australia, with a long history of sheep grazing. Pygmy bluetongue lizards use ambush predation from their burrow entrances, and prey capture may be more efficient in a habitat with low vegetation density. We experimentally investigated changes in predatory behaviour in this lizard, with different grass density.

Black-fronted tern (Chlidonias albostriatus) breeding populations on braided rivers in the South Island, New Zealand, are assumed to be in decline as their habitat comes under increasing pressure from exotic pests, hydroelectric power development and water abstraction. We collated 326 index counts of black-fronted terns from 2313 km of surveys on 84 rivers throughout their breeding range to test this assumption. Black-fronted terns were observed on 73% (n = 61) of rivers surveyed, and the sum of the most recent counts was 8325 birds.