The Gambia River estuary: A reference point for estuarine fish assemblages studies in West Africa

The northern coast of Brazil has more than 30 estuaries distributed along 650 km of coastline. These conditions favor the presence of relatively large fish communities in estuarine environments, but published information on the fish fauna in tidal creeks in northern Brazil is only available for some mangrove systems, and comparative studies between fish estuarine communities in different tidal creeks are less common. The choice of the study area was based on the fact that it has been poorly investigated with regard to estuarine fish fauna in comparison in mangrove tidal creeks using the same fishing gear. The objective of the present study was to compare the composition of the relative biomass of taxonomic, functional and ecological guilds of fish assemblages occurring in estuarine systems along the northern coast of Brazil. The study area of the present comparative analysis extended from the southeastern edge of the Marajoara Gulf to the western edge of the Maranhense Gulf. A comparative analysis among different estuarine systems was performed using data from other studies. The abundance of juveniles was greater in the Caeté, Curuçá and Cururuca estuaries than other estuaries. Cluster analysis separated the estuaries into two distinct groups and significant differences between these groups only exist in relation to geographical proximity. The present investigation indicates that the coastal region between the states of Pará and Maranhão is characterized by high dynamics and environmental heterogeneity, particularly with regard to changes in river discharge and tidal fluctuations. The present results underscore the importance of ecological information on ichthyofauna in tropical estuaries in order to include appropriate descriptors in conservation or restoration processes of marine communities and habitats.

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Aflatoxin Exposure and Viral Hepatitis in the Etiology of Liver Cirrhosis in The Gambia, West Africa

Environmental Health Perspectives ◽

10.1289/ehp.11661 ◽

2008 ◽

Vol 116 (11) ◽

pp. 1553-1557 ◽

Cited By ~ 29

Author(s):

Mark H. Kuniholm ◽

Olufunmilayo A. Lesi ◽

Maimuna Mendy ◽

Aliu O. Akano ◽

Omar Sam ◽

...

Keyword(s):

Liver Cirrhosis ◽

West Africa ◽

Viral Hepatitis ◽

The Gambia

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The contribution of environmental factors to fish assemblages in the Río Acahuapa, a small drainage in Central America

Neotropical Ichthyology ◽

10.1590/1982-0224-20170023 ◽

2017 ◽

Vol 15 (3) ◽

Cited By ~ 1

Author(s):

Francisco S. Álvarez ◽

Wilfredo A. Matamoros ◽

Francisco A. Chicas

Keyword(s):

Fish Species ◽

Habitat Structure ◽

Fish Assemblages ◽

Species Abundance ◽

Main Channel ◽

Estuarine Fish ◽

Species Origin ◽

High Temperature Water ◽

Distribution Of Fish ◽

Temperature Water

ABSTRACT The ichthyofauna of the Río Acahuapa was analyzed sampling 17 sites that included the basin main channel and its tributaries. Fish were collected using dip-nets, seine-nets and electrofishing. Fish standard length and species abundance were recorded. Species origin and salinity tolerance criteria were used to classify fish species. Water physicochemical variables, habitat structure and sampling sites elevation were recorded. A total of 33 fish species were registered, 12.1% are primary, 45.5% are secondary and 42.4% are of marine derivation. Fish species richness declined with increase of elevation (R2=0.55, p=0.0006). Two assemblages of fishes were identified: the first one associated to sites of low elevations (19-184 masl), composed mainly of secondary and marine-estuarine fish species related with high temperature, water velocity, river width, dissolved oxygen and low sand and silt substrate cover; the second one associated to sites of middle and higher elevations (185-519 masl), composed by primary and secondary freshwater fishes related with high pH, logs and rocks substrate cover. In summary, elevation and environmental variables contributed to the composition and distribution of fish in the Río Acahuapa.

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