Nest‐site selection by crocodiles at a rocky site in the Australian tropics: Making the best of a bad lot

摘要: Most animals select nest sites non-randomly, reflecting benefits of specific locations or incubation conditions for offspring viability as well risks costs to the reproducing adult. If few no available offer suitable conditions, we expect make best a bad lot, by selecting that provide available. In tropical north-western Australia, freshwater crocodiles (Crocodylus johnstoni: Crocodylidae) in large artificial lake (Lake Argyle) experience this challenge: types used species other parts its range (moist, shaded sandy soils, far from water's edge) are scarce. Measurements 89 crocodile nests and test holes (abandoned attempts at nesting) Lake Argyle, 28 on nearby Ord River, show most areas along lakeshore too steep rocky nesting. Crocodiles therefore forced sun-exposed, dry gravelly substrates, close edge. Comparisons actual within such nesting actively less rocky, hydrically, stable thermal regimes. Those hydric attributes allow successful development offspring. The ability Argyle flexibly modify their nest-site selection criteria, under severe constraints enforced open landscape, critical species' success exploiting opportunity created dam's construction.