Longitudinal structure, density and production rates of a neotropical stream fish assemblage: the river Ubatiba in the Serra do Mar, southeast Brazil

Abstract

Spatio‐temporal variations in the structure, density, biomass and production rates of fish were assessed in the neotropical River Ubatiba (Serra do Mar, southeast Brazil). Electrofishing techniques and the length‐frequency method were shown to be reliable for the assessment of (ish numbers and production rates in these running waters of medium conductivity. Eighteen fish species of small size and prolonged spawning period were broadly distributed throughout the river catchment. Over the year, the assemblage structure was persistent along the river. Water column omnivore and algae/detritivore species dominated in density (15086‐70330 ind. ha−1), whereas three omnivores and a piscivorous species accounted for 70% of the production (51.5‐250.4 kg ha−1 yr−1). Comparison of production rates among, tropical, temperate and Mediterranean stream fish assemblages indicate lower rates in tropical streams and an inverse relationship between production and species diversity, lower production rates in high‐diversity tropical streams vs higher rates in low‐diversity Mediterranean streams, with intermediate rates in temperate streams of intermediate diversity.

Ichthyofauna of Rio Jurubatuba, Santos, São Paulo: a high diversity refuge in impacted lands

“…Almost all Siluriformes sampled are also endemic of the Atlantic Rainforest. This well illustrates the high endemism of fishes in this biome pointed out by many authors (Bizerril 1994, Mazzoni & Lobón-Cerviá 2000, Sabino & Silva 2004, Sazima 2004, Oyakawa et al 2006. Besides the high endemism of the ichthyofauna in the study area, four species are listed as vulnerable or in danger in local lists, including Hollandichthys multifasciatus (Rio Grande do Sul), Acentronichthys leptos (Rio de Janeiro and Espírito Santo), Kryptolebias caudomarginatus and K. ocellatus (both in Rio de Janeiro) (Buckup et al 2007).…”

“…Despite of not being vaslty explored from an ichthyofaunistic point of view, the Atlantic Rainforest is known to possess a fish fauna characterized by a high level of endemism (Bizerril 1994, Mazzoni & Lobón-Cerviá 2000, Sazima 2004). The high number of endemic fish species in the coastal rivers of the Atlantic Forest is an aggravating factor in respect to the conservation policies of these areas as this biome is located in the most populated regions of the country, making these rivers especially vulnerable to anthropogenic impacts (Bizerril 1994, Mazzoni & Lobón-Cerviá 2000, Gerhard et al 2004.…”

“…Detailed publications regarding fish communities of the Atlantic Rainforest include basins from the states of Bahia, Rio de Janeiro, São Paulo, Paraná and Rio Grande do Sul (Costa 1987, Buck & Sazima 1995, Araújo 1996, Aranha et al 1998, Mazzoni & Lobón-Cerviá 2000, Esteves & Lobón-Cerviá 2001, Fogaça et al 2003, Vilella et al 2004 (Sabino & Castro 1990, Uieda, V.S. & Uieda, W. 2001, Sabino & Silva 2004, Oyakawa et al 2006, leaving a lack in the knowledge regarding the vast central portion, highly impacted by human activities.…”

“…The high number of endemic fish species in the coastal rivers of the Atlantic Forest is an aggravating factor in respect to the conservation policies of these areas as this biome is located in the most populated regions of the country, making these rivers especially vulnerable to anthropogenic impacts (Bizerril 1994, Mazzoni & Lobón-Cerviá 2000, Gerhard et al 2004.…”

Composition and structure of fish assemblage from Passa Cinco stream, Corumbataí river sub-basin, SP, Brazil

“…Spatial patterns of species distribution have been addressed in several studies (Uieda, 1984;Garutti, 1988;Uieda and Barreto, 1999;Silvano et al, 2000;Mazzoni and Lobón-Cerviá, 2000;Uieda and Uieda, 2001;Pavanelli and Caramaschi, 2003;Castro et al, 2003;Súarez and Petrere, 2003;Súarez and Petrere, 2005;Castro et al, 2004;Casatti, 2005;Braga and Andrade, 2005;Cetra and Petrere, 2006) that, in general, reported an increase in species diversity since the headwaters to the mouth in fish communities at different locations. The relationship between habitat and community composition was presented by Montag et al (1997), Benedito-Cecilio et al (2004) and Gomiero and Braga (2006), which showed the correlations between habitat diversity and general conditions in the environment.…”