PREDATOR-PREY INTERACTIONS BETWEEN LEPSIELLA (BEDEVA) PAIVAE (GASTROPODA: MURICIDAE) AND KATELYSIA SCALARINA (BIVALVIA: VENERIDAE) IN PRINCESS ROYAL HARBOUR, WESTERN AUSTRALIA

• Published in: Journal of Molluscan Studies
• Main Author: MORTON, BRIAN
• Format: Text
• Language: English
• Published: Oxford University Press 2005
• Subjects: Article; Southern Ocean; Austral; Sandy Beach
• Online Access: http://mollus.oxfordjournals.org/cgi/content/short/eyi049v1; https://doi.org/10.1093/mollus/eyi049

On a sandy beach at Shoal Bay in Princess Royal Harbour, Albany, southwestern Western Australia, lives a small muricid gastropod that feeds virtually monotonically on the overwhelmingly dominant resident bivalve Katelysia scalarina. Lepsiella paivae lives buried in the sand and attacks its prey within it. Because of its small size (<13 mm shell height), bivalve prey is also small and this study demonstrates a preference for K. scalarina of 5 mm shell length, i.e. juveniles. Laboratory experiments also suggested a possible preference for attack of the right valve. Lepsiella paivae can and does, however, attack larger prey (up to 15 mm shell length), but cannot consume them completely. A second visit to Princess Royal Harbour in the Austral winter, when there was no juvenile K. scalarina present, showed L. paivae to be attacking at the sand surface, also by drilling, the small (<4 mm) gastropod Hydrococcus brazieri (Hydrococcidae). SEM studies of experimentally determined drill holes of L. paivae show them to be of variable form, some straight sided, others bevelled (like a naticid) and < 500 µm in diameter. On this sheltered Southern Ocean beach, therefore, L. paivae has specialized to attack juvenile bivalves by burrowing after them. It can, however, attack other species opportunistically on the sand surface when seasonally favoured juvenile bivalve prey are not present.