Search results for "Lepomis"

2002

We carried out enclosure experiments to assess the potential deleterious effects of the alien species common carp (Cyprinus carpio L.), mosquitofish (Gambusia holbrookii Gir.), and pumpkinseed sunfish (Lepomis gibbosus L.) on water quality and food web in a severely degraded floodplain wetland, the Spanish National Park Las Tablas de Daimiel. With addition of either carp or pumpkinseed sunfish, chlorophyll a and turbidity levels, as well as concentrations of total phosphorus and total nitrogen increased. The magnitude of this increase depended on fish species and was severest in the carp treatment. Mosquitofish did not significantly affect water quality. In the treatments with fish, cyclopo…

Fish communities and food web interactions in some shallow Mediterranean lakes

2003

Fish communities of five shallow Spanish Mediterranean lakes were studied and stomach content analysed to determine the foraging pattern of each species and the influence on the lake food web. Lakes ranged from 0.5 to 2300 ha with less than 3 m mean depth, while the trophic state varied from mesotrophy to hypertrophy. We fished during summer 2000 and 2001, and for one lake also during spring 2002. Almost no piscivores species were recorded and in general omnivorous species dominated independently of lake trophic state. Fish dietary differences were found among lakes and prey availabilities. Maximum fish biomass and diversity were found in the Albufera lake, where mugilids (Mugil cephalus an…