Abstract

MENDEZ, María M; ROBLEDO, Jorgelina  and  VAN DER MOLEN, Silvina. Infaunal communities associated to the razor clam Ensis macha: water-jet fishing impact. Ecol. austral [online]. 2017, vol.27, n.3, pp.474-481. ISSN 1667-782X.

Razor clams (genus Ensis) are exploited worldwide through a variety of fishing gears. The environmental impacts produced by these fisheries include changes in the sediment physical characteristics and the water column, as well as the effects on the associated communities and on the target species. The impact mainly depends on the fishing gear, the type of habitat and the fishing intensity. San José gulf (Península Valdés, Chubut) fishermen use the water-jet technique, which involves the injection of water into the substrate to extract the razor clams. Although the exploitation of this resource in the San José gulf is still incipient, it is important to study the impact of this fishery in order to establish appropriate management measures to related the technique used and to the gulf environment, before the fishery grows. Thus, the aim of this study was to experimentally evaluate the impact of Ensis macha water-jet fishing on the benthic communities associated with its beds in San José gulf. The composition of the benthic fauna was compared in two beds, one with extractive activity and another as control, at the time of fishing and after a year. Comparisons showed no differences in the initial time between the impacted bed and the control one, while after a year of the fishing activity the differences in the communities' composition of both beds were significant. The control bed was characterized by polychaetes, amphipods and stomatopods, while the bivalves and gastropods were representative of the impacted bed. The results found are useful in suggesting conservation and management measures to avoid degradation of local biodiversity.

Keywords : Patagonia; Suficiencia taxonómica.