Predator–prey interactions from in situ time-lapse observations of a sublittoral mussel bed in the Gulf of Trieste (Northern Adriatic)

摘要: Abstract Hexaplex trunculus (Linnaeus, 1758) is one of the most abundant and widespread muricid gastropods in Northern Adriatic Sea, but relatively little known about feeding ecology this predator. We examined activity H. on a sublittoral mussel bed at 24 m depth through situ time-lapse observations bulk samples. The camera photographed 0.25 m2 section 6-min intervals for ~ 23 h. Photos were frame-by-frame gastropod movement activities, especially interactions between Mytilus galloprovincialis (Lamarck, 1819). Our survey indicates high activity-levels sea floor: all made minor movements, major left field view during study-interval. On average, individuals remained stationary only 7.3 h. Two predation attempts involving conspecific competition documented, was consuming onset deployment. Additionally, 487 M. from four diver-taken quadrates measured traces marginal chipping drilling predation. surface samples ranged 11.1 mm to 95.5 mm length, had significantly different average shell length others. 114 collected measured. 22.1 mm 86.1 mm mean did not differ among samples, though they overwhelmingly medium large. Predation frequency (the ratio successfully preyed upon bivalves total number sampled) studied site (> 55%), large preferred mode drilling, supporting earlier laboratory studies showing preference strategy. Prey effectiveness failed predatory attacks attacks) also (63.8%), no evidence size refuge found. Feeding highly facultative, calling caution when using drill holes estimate intensities; whenever possible, multiple modes should be considered.