siphon nipping of the bivalve amiantis purpurata by the electric ray discopyge tschudii in mar del plata, argentina

Autor:	Juan Pablo Livore, Pablo E. Penchaszadeh, Florencia Arrighetti
Rok vydání:	2005
Předmět:	education.field_of_study biology Ecology Population Electric ray Zoology Aquatic Science Bivalvia biology.organism_classification Chondrichthyes Discopyge tschudii Siphon Discopyge education Mollusca
Zdroj:	Journal of the Marine Biological Association of the United Kingdom. 85:1151-1154
ISSN:	1469-7769 0025-3154
DOI:	10.1017/s0025315405012221
Popis:	a total of 67 discopyge tschudii was captured. individuals were sexed, measured and their stomach content analysed. siphon tips of the bivalve amiantis purpurata from each stomach were individually counted, weighed and their length and width measured. the size–frequency distribution of the local population of a. purpurata was surveyed for two years. siphons of a. purpurata were the main food item in 90% of individuals having stomach contents. the clam population was markedly bimodal, with 24 mm and 46 mm mean shell length for the younger and older size-classes, respectively. grazing by d. tschudii on a. purpurata varied with size and sex of the fish. small rays mainly ingested small siphons and large rays large siphons. nipped siphon tips were longer in male than in female rays.
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_________::f3b5d33e859069d7b5a7181baaa6755a https://doi.org/10.1017/s0025315405012221 Zobrazit plný text záznamu