Regionally nested patterns of fish assemblages in floodplain lakes of the Magdalena river (Colombia).

摘要: We investigated if fish assemblages in neotropical floodplain lakes (cienagas) exhibit nestedness, and thus offer support to the managers of natural resources area for their decision making. The location was middle section Magdalena river, Colombia. applied nested subset analysis series 30 cienagas (27 connected main river three isolated). All were identified taxonomically field matrix presence–absence all used study pattern nestedness. most diverse order Characiformes (20 species), followed by Siluriformes (19 species). Characidae Loricaridae richest families. species found studied migratory (17), sedentary (33). Two (Caquetaia kraussii Cyphocharax magdalenae) widespread across archipelago (100% incidence). Nestedness showed that distribution over spatial gradient (840 km) is significantly nested. deemed hospitable Simiti, El Llanito, Canaletal. Roughly, 13 out 50 caught show markedly idiosyncratic distributions. resulting dataset a strong nestedness Magdalenese fishes, differed from random assemblages. Out measurements taken cienagas, only size (area) local richness are related range patterns (r=–0.59 –0.90, respectively, at p < 0.01). Differential extinction suggested as cause assemblage, when reorganized occurring habitat islands correlated with island area. Our results consistent this hypothesis.