Population, reproductive and ecological aspects of the music volute Voluta musica (Caenogastropoda: Volutidae) in northeastern Venezuela

Voluta musica is considered an endangered species in Venezuela for two main reasons: collectors appreciate shells and its incidental catch in fishery of Arca zebra. Population and ecological parameters including abundance, distribution, reproduction, length-frequency distributions, color pattern of shells and influence of biotic and abiotic factors on density were estimated through observations by line transect samples. Between February/2008 and January/2009, 178 individuals were collected, with an average total length of 56.4 ± 28.3 mm, in Coche Island and coast of the Araya peninsula. Average monthly density was 0.037 ± 0.17 org/m with a maximum value in September (0.12 org/m) and a minimum in October (0.0067 org/m). GLM showed that the factors with high influence on densities were: absence of A. seminuda, presence of muddy-fine grain sand and medium-grain sand bottoms, the zone corresponding to the channel between Coche Island and Morro de Chacopata. Egg capsules were found in dead shells of A. seminuda, Pinna carnea and Anadara floridana. The number of egg capsules found indicates a spawning period between June and November with a peak in August. We recommend estimating catches of music volutes in the ark shellfishery to assess the impact of this activity on their populations.