63 research outputs found

    Tuna Baitfish and the Pole-and-line Industry in Kiribati

    Get PDF
    Livestock Production/Industries, Resource /Energy Economics and Policy,

    A new freshwater Goby (Teleostei: Gobiidae) from the Pongolo floodplain, Zululand, South Africa

    Get PDF
    A new freshwater goby, Mugilogobius pongolensis sp. n. is described and figured as a species new to southern and eastern Africa. This record extends the zoogeographcal distribution of Mugilogobius Smitt, 1899, from the Indonesian archipelago and South Australia to the Indian Ocean and the eastern coast of Africa

    Species identification, distribution and abundance of Gerreidae (Teleostei) Bleeker,1859 in the estuaries of Natal

    Get PDF
    Comparison of published meristic and taxonomic data with measurements taken from specimens collected from Natal estuaries have provided information for an identification key to the Gerres of southern Africa. Body markings were different on each species of fry (< 40 mm S.L.) as well as immatures and adults (> 40 mm S.L.). A comparison of otoliths from the different species showed that they can be used to Identify specimens from a standard length of 20 mm. Turbidity may be a factor limiting the distribution of the genus in estuaries. The known distribution of Gerres species in the estuaries of southern Africa is given. The species of Gerres which is dominant in a particular locality depends on the salinity

    The feeding ecology of Ambassidae (Osteichthyes: Perciformes) in Natal estuaries

    Get PDF
    The diets of three species of Ambassis in six estuaries of southern Africa were investigated using four methods of stomach content analysis. Diets varied from one estuary to another as the faunal composition changed according to physical conditions. Ecological separation among the species is achieved to a large extent through diet alone. While all Ambassis feed mainly on a wide variety of zooplankters, Ambassis productus and A. natalensis are also piscivorous and insectivorous respectively. Seasonal analysis of diet showed that A. gymnocephalus feeds mainly on fish eggs during winter (June-August). The possible impact of egg predation on fish numbers at St Lucia is discussed. Feeding periodicity was investigated using dry mass and volumetric methods. All Ambassisshowed similar bimodal feeding intensities during the night with peaks in early evening and early morning. Food selection at different levels in the water column showed that all Ambassis feed mainly on food in suspension. Additionally A. natalensis feeds on surface prey while A. productus takes ben-thic prey. It is postulated that interaction between Ambassis and filter-feeding planktivores in St Lucia is minimal due to feeding strategies and feeding periodicity. In addition the impact of the piscivorous predatory role played by Ambassis on estuarine fish communities is emphasized

    Analysis of fish assemblages in sectors along a salinity gradient based on species, families and functional groups

    Full text link
    • …
    corecore