Role of food availability in the bathymetric distribution of the starfish "Marthasterias glacialis" (Lamk.) on reefs of northern Portugal
We examined whether the abundance and size of the starfish Marthasterias glacialis (Lamk.) exhibit a depth-dependent partitioning on subtidal reefs. We tested the hypothesis that differences in food availability can result in habitat partitioning along a depth gradient. The abundance and size of M....
| Autores: | , |
|---|---|
| Tipo de recurso: | artículo |
| Fecha de publicación: | 2012 |
| País: | España |
| Repositorio: | accedaCRIS portal de investigación de la Universidad de las Palmas de Gran Canaria |
| OAI Identifier: | oai:accedacris.ulpgc.es:10553/57431 |
| Acceso en línea: | http://hdl.handle.net/10553/11437 http://hdl.handle.net/10553/57431 http://dialnet.unirioja.es/servlet/articulo?codigo=5290311 |
| Access Level: | acceso abierto |
| Palabra clave: | 2401 Biología animal (zoología) Starfish Vertical distribution Segregation Food availability Spatial patterns Portugal |
| Sumario: | We examined whether the abundance and size of the starfish Marthasterias glacialis (Lamk.) exhibit a depth-dependent partitioning on subtidal reefs. We tested the hypothesis that differences in food availability can result in habitat partitioning along a depth gradient. The abundance and size of M. glacialis was registered at 4 depth strata: 0-4 m, 4-8 m, 8-12 m, and >12 m; we also recorded the number of food items that they were preying on. The abundance and size of M. glacialis decreased with depth. Mussels (Mytilus galloprivincialis) were the most preyed food item across all depth strata, followed by gastropods, sea urchins and barnacles; M. glacialis also consumed a significantly larger amount of mussels in feeding experiments compared with sea urchins and gastropods. The abundance of M. galloprivincialis beds decreased with depth. The clear link between the decrease in abundance and size of M. glacialis with depth and the decay of the most consumed prey (mussels) suggest that food availability may play an important role in the vertical distribution of this starfish, though wave-associated turbulence in the first few metres of the subtidal could also limit the abundance of M. glacialis. |
|---|