MASS MORTALITIES AFFECTING POPULATIONS OF THE YELLOW CLAM

VÁZQUEZ NURIA; FIORI SANDRA; ARZUL ISABELLE; CARCEDO CECILIA; CREMONTE FLORENCIA

JOURNAL OF SHELLFISH RESEARCH

NATL SHELLFISHERIES ASSOC

Año: 2016 vol. 35 p. 739 - 745

0730-8000

The yellow clam Amarilladesma mactroides (Deshayes, 1854) is considered a vulnerable species since the mid-1990s.Populations have experienced mass mortalities throughout their entire range of distribution (23?41S) along exposed sandy beaches ofAtlantic South America. Detrimental anthropogenic impacts have further contributed to failure of populations to make a recovery. Todetermine the factors involved in these events, density prior to a mortality event was calculated and live yellow clams encompassingmostof its geographic range distribution were analyzed histologically to describe parasites and pathologies. Moreover, moribund specimenswere analyzed by molecular techniques to test for the presence of the virus OsHV-1. A mortality event was recorded after a maximumdensity of 127 clams/m2 was attained. No clear pattern was found between the prevalence and intensity of infection and localities,mortality events, or sampling season. Although OsHV-1 was not observed in any of the yellow clams tested, the possibility that anotherviral agent was implicated cannot be ruled out. The presence of bacteria of the genus Vibrio in combination