open access

https://hdl.handle.net/2115/86983

Prey utilization by Neptunea arthritica (Caenogastropoda: Buccinidae) : predation on gastropods and size-related variation

英語

2021-06

Oxford University Press

The Journal of molluscan studies

87

eyab016

The whelk Neptunea arthritica (Buccinidae) is a common fishery species in Hokkaido, northern Japan. Although ecological information is needed for fisheries management, there is only one paper examining the foraging ecology of this species and it reported that N. arthritica preyed mainly on the invasive mussel Mytilus galloprovincialis. To date, no studies have examined utilization of native prey species by this whelk. Here, we report the findings of a study on the native prey utilization by N. arthritica in an area where M. galloprovincialis is not present. We conducted line transect sampling every month from May 2018 to May 2019 on the western coast of Hakodate Bay, southwestern Hokkaido, Japan. Prey items were composed mostly of gastropods (72%), followed by bivalves (24%) and only a small amount of carrion (<4%). Overlapping spatial distributions were observed among size classes of N. arthritica, while the prey utilization varied with body size. Small individuals (<30 mm in shell height) preyed mainly on the small colloniid gastropod Homalopoma sangarense, while larger individuals (>40 mm) preyed mainly on two tegulid gastropods (C,hlorostoma lischkei and Omphalius rusticus) and two venerid bivalves (Rotothaca euglypta and Ruditapes philippinarum). There were positive size relationships between whelk body size and prey size for prey categories (Vetigastropoda, Caenogastropoda and Bivalvia) and even for the same prey species (H. sangarense, O. rusticus and P. euglypta). These results suggest that N. arthritica is a predator of mobile gastropods, especially during its early life stage, in areas without the invasive Mediterranean mussel. It is possible that the foraging strategy of N. arthritica may differ quite markedly between areas with and without the invasive mussel.

学術雑誌論文

Author's Original

This is a pre-copyedited, author-produced version of an article accepted for publication in "The Journal of molluscan studies" following peer review. The version of record "Prey utilization by Neptunea arthritica (Caenogastropoda: Buccinidae): predation on gastropods and size-related variation" is available online at: https://academic.oup.com/mollus/article/87/2/eyab016/6285210.

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