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Providing evidence to improve practice

Individual study: Rebuilding viable spawner patches of the overfished Spisula solida (Mollusca: Bivalvia): a preliminary contribution to fishery sustainability

Published source details

Joaquim S., Gaspar M.B., Matias D., Ben-Hamadou R. & Arnold W.S. (2008) Rebuilding viable spawner patches of the overfished Spisula solida (Mollusca: Bivalvia): a preliminary contribution to fishery sustainability. ICES Journal of Marine Science, 65, 60-64


This study is summarised as evidence for the intervention(s) shown on the right. The icon shows which synopsis it is relevant to.

Translocate species - Translocate molluscs Subtidal Benthic Invertebrate Conservation

A replicated, site comparison study in 2003–2004 of two sites off the coast of Algarve, North Atlantic Ocean, southern Portugal (Joaquim et al. 2008) found that after translocation, clams Spisuloa solida were in similar condition to clams in the source site, and that despite increased mortality over time 45% survived up to a year. Before translocation, the condition of all clams was 6.3 (ratio without units). After three months, conditions were similar for translocated (6.4–6.5) and source site clams (7.4–7.8). Survival of translocated clams was 65-85% after two weeks, 52-60% after three months, and 45% after a year. Size of translocated clams did not affect survival or condition. In 2003, a total of 4,000 clams were translocated from a source site to two 50 m2 plots in a depleted site (1 clam/m2) inside an area closed to fishing. Each plot was sub-divided into fifty 1 m2 subplots. Clams, divided into sublegal (<25 mm shell length) and legal (>25 mm) size groups, were equally distributed to each subplot. After two weeks and three months, all clams/subplot were counted, and the condition index of 10 clams/subplot assessed. Clam condition was also assessed for the source site. After a year, all clams in the translocation site were counted.

(Summarised by Anaëlle Lemasson)