Effects of protection on the demographic structure and abundance of Epinephelus marginatus (Lowe, 1834). Evidence from the Cabrera Archipelago National Park (West Central Mediterranean)
This study investigates the effects of the cessation of fishing on the density, size structure and depth distribution of dusky grouper, Epinephelus marginatus (Lowe, 1834) (formerly E. guaza) in the Cabrera Archipelago National Park (Balearic lslands, Western Mediterranean). Underwater visual counts...
| Autores: | , , , , |
|---|---|
| Tipo de recurso: | artículo |
| Fecha de publicación: | 1999 |
| País: | España |
| Institución: | Consejo Superior de Investigaciones Científicas (CSIC) |
| Repositorio: | DIGITAL.CSIC. Repositorio Institucional del CSIC |
| OAI Identifier: | oai:dnet:digitalcsic_::e22de101405a692220c812d72ebbf1d4 |
| Acceso en línea: | http://hdl.handle.net/10261/317741 |
| Access Level: | acceso abierto |
| Palabra clave: | Centro Oceanográfico de Baleares Epinephelus marginatus Medio Marino effects of protection marine reserve Mediterranean Sea effets de la protection réserve marine mer Méditerranée |
| Sumario: | This study investigates the effects of the cessation of fishing on the density, size structure and depth distribution of dusky grouper, Epinephelus marginatus (Lowe, 1834) (formerly E. guaza) in the Cabrera Archipelago National Park (Balearic lslands, Western Mediterranean). Underwater visual counts of E. marginatus were carried out on rocky substrates at depths of 5-10 m and 20-25 m during the summers of 1996 and 1998. Counts were done in areas of the Park closed to all fishing (since 1995) and closed only to sport fishing (since 1991) and in locations outside the Park open to all fishing. The two depth strata were chosen to evaluate possible bathymetric changes in distribution and size structure of E. marginatus as a result of the protection measures. In the Park, mean density of dusky grouper was higher in 1998 than in 1996. The size distribution also differed between the two time periods exhibiting a tendency towards rebuilding the natural size structure over time. The comparison of the E. marginatus population in the Park with those in areas open to all fishing corroborates the increase in mean density reported in other studies of Mediterranean marine protected areas. The size composition in exploited areas evidences a narrowing of the size structure with the virtual disappearance of small and large individuals. The results of the temporal and spatial comparisons suggest a strong response to protection or “reserve effect” in the population of E. marginatus in the Cabrera Archipelago National Park. |
|---|