The biogeography and evolution of Australian land snails

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“…Snails were found to be only nocturnally active, as previously noted by Jahnsen (1967), Shea (1978) and Bishop (1981), and were more likely to be active and to move greater distances on rainy nights than dry nights, consistent with earlier comments by Jahnsen (1967). McMichael and Iredale (1959) reported that, in general, the large land snail species from eastern Australian rainforests are very sensitive to dry conditions, appearing only at night and after rain and hiding away in moist places at other times.…”

“…Many gardeners would probably attest to the veracity of the correlation between snail activity and wet nights. Bishop's (1981) description of H. falconeri as a ground living species not climbing more than 0.5 m was also supported by the present study, with almost 90% of all movement recorded over the course of the study occurring on the ground surface and most climbing limited to passage over low obstacles, such as tree roots and fallen logs. Unlike sympatric land snail and slug species, such as Thersites novaehollandiae (Camaenidae) and Triboniophorus graeffei (Athoracophoridae), which can often be observed at moderate to high heights on tree trunks as well as on the ground (personal observations), H. falconeri does not appear to forage or shelter in trees.…”

“…Jahnsen (1967) suggested that the selection of secure diurnal shelter sites was essential for H. falconeri to avoid predation by diurnal ground foraging rainforest birds and reported finding snails sheltering under large rocks and slabs of fallen timber. Bishop (1981) reported that H. falconeri preferred diurnal shelter sites among the twisted roots of strangler fig trees, implying a high degree of active site selection. The results presented here do not support the notion of active and frequent selection of secure diurnal shelter sites.…”

“…McMichael and Iredale (1959) noted that whereas the taxonomic study of Australia's land and freshwater Mollusca was far from complete, their ecology had received practically no attention. Bishop (1981) noted that the majority of Australian land snail research had focused on taxonomic studies based largely on shell morphology, to the neglect of biological or ecological studies of the living animals. Smith (1992) noted that a large proportion of Australia's terrestrial and freshwater mollusc species had never been observed in their natural habitat, with no information available on even their basic biology.…”

“…Shea (1978) noted that H. falconeri was nocturnal, hiding by day under logs, heaps of leaves and sticks. Bishop (1981) described H. falconeri as a ground feeding species, not climbing more than 50 cm or so. He noted that it was very difficult to find by day, with a preference for giant strangler figs as diurnal shelter sites, but easily found at night on the ground around fig trees.…”