Predation on egg capsules of Emphasis Type="Itali

Authors: Andrea Roche Matías Maggioni Maite Narvarte

Publish Date: 2011/08/23

Volume: 158, Issue: 12, Pages: 2787-2793

PDF Link

Abstract

Among the diverse patterns of energy allocation to the offspring of gastropods the presence of egg capsules to protect embryos is common Females of the edible snail Zidona dufresnei attach egg capsules to hard substrates in shallow Argentine Patagonian waters 40°45′S 64°56′W during springsummer Embryonic development takes about 30 days at 22°C In this study three likely capsule predator species and the marks left by each on egg capsule walls were identified in laboratory experiments in February 2010 Abundances of predators and egg capsules with evidence of predation were assessed in the field in the summers of 2010 and 2011 Under laboratory conditions N = 10 replicates per treatment and control the predation rate by the chiton Chaetopleura isabellei was the highest up to 90 followed by the gastropod Tegula patagonica and the crab Neohelice granulata ~20 each Nearly 60 of 41 capsules found in the field showed signs of predation According to the marks identified in the laboratory C isabellei was responsible for 79 of this predation and T patagonica for the rest Predation appears to be important during the encapsulated early life and could be an agent for selecting for resistant capsule walls and a relatively shorter development timeWe thank the staff of the Instituto de Biología Marina y Pesquera Almirante Storni Ministry of Production of Río Negro Province and National University of Comahue Argentina We also thank two anonymous reviewers who made useful comments on the original version of the manuscript This research was supported by Project PICTStart up 1575 Agencia Nacional de Promoción Científica y Tecnológica

Keywords: