Articles by Author: Mj Gibbons

Search results for Mj Gibbons

We found 27 results for you
  1. Video observations on the habitat association of demersal nekton in the midshelf benthic environment off the Orange River, Namibia

    Video observations on the habitat association of demersal nekton in the midshelf benthic environment off the Orange River, Namibia

    Item type: Journal Article • Journal: South African Journal of Marine Science
    A semi-quantitative assessment is made of the animals observed in archived videotapes taken from the research submersible Jago, during diamond mining and exploratory surveys off the mouth of the Orange River on the west coast of southern Africa (28°15′S, 29°11′S)...
  2. Determination of moult stage in the South African West Coast rock lobster <em>Jasus lalandii</em> (h. Milne Edwards) (Crustacea: Decapoda)

    Determination of moult stage in the South African West Coast rock lobster <em>Jasus lalandii</em> (h. Milne Edwards) (Crustacea: Decapoda)

    Item type: Journal Article • Journal: South African Journal of Marine Science
    Nine stages and substages of post-, inter- and premoult were distinguished in the West Coast rock lobster Jasus lalandii by microscopic examination of the cuticle, epidermal retraction and setal development in the pleopods. The postmoult condition is characterized by progressive...
  3. Genetic and morphological variation of the lanternfish <em>Lampanyctodes hectoris</em> (Myctophiformes: Myctophidae) off southern Africa

    Genetic and morphological variation of the lanternfish <em>Lampanyctodes hectoris</em> (Myctophiformes: Myctophidae) off southern Africa

    Item type: Journal Article • Journal: South African Journal of Marine Science
    Genetic and morphological variation within the southern African population of Lampanyctodes hectoris was analysed. A total of 15 enzymes, encoding 22 isozyme loci, was examined (n = 327); seven were polymorphic. The percentage of polymorphic loci ranged from 13.6 to...
  4. An improved quantitative method for estimating intertidal meiofaunal standing stock on an exposed rocky shore

    An improved quantitative method for estimating intertidal meiofaunal standing stock on an exposed rocky shore

    Item type: Journal Article • Journal: South African Journal of Marine Science
    A method for sampling the meiofauna of rocky shores on a quantitative per unit area basis is proposed, making such data comparable with those for macrofauna and sediment meiofauna. To date, densities of rocky-shore meiofauna have been estimated by counting...
  5. Tidal migration of <em>Porcellidium</em> (Copepoda: Harpacticoida) on fronds of the rocky shore alga <em>Gigartina radula</em> (Esper) J. Agardh (Gigartinales: Rhodophyta)

    Tidal migration of <em>Porcellidium</em> (Copepoda: Harpacticoida) on fronds of the rocky shore alga <em>Gigartina radula</em> (Esper) J. Agardh (Gigartinales: Rhodophyta)

    Item type: Journal Article • Journal: South African Journal of Marine Science
    Movement of the harpacticoid copepod Porcellidium sp. on blades of Gigartina radula was monitored over a 24-h tidal cycle. A comparison was made between plants in pools and those on tidally exposed rock. In general, Porcellidium move to the base...
  6. Community structure and trophic ecology of euphausiids in the Benguela ecosystem

    Community structure and trophic ecology of euphausiids in the Benguela ecosystem

    Item type: Journal Article • Journal: South African Journal of Marine Science
    Current knowledge of the community structure, life history strategies and trophodynamics of euphausiids in the Benguela ecosystem is synthesized. Three species dominate, Euphausia lucens over the shelf region of the southern Benguela, Euphausia hanseni over the outer shelf off Namibia...
  7. Tropidc ecology of carnivorous zooplankton in the Benguela

    Tropidc ecology of carnivorous zooplankton in the Benguela

    Item type: Journal Article • Journal: South African Journal of Marine Science
    Carnivorous zooplankton in the Benguela system have tended to be ignored by all but early taxonomists and a handful of recent researchers. An attempt is made here to address the importance of carnivores in this system but, because the database...
  8. Feeding and vertical migration of the chaetognath <em>Sagitta friderici</em> (Ritter-Zahony, 1911) in the southern Benguela during spring 1987, with notes on seasonal variability of feeding ecology

    Feeding and vertical migration of the chaetognath <em>Sagitta friderici</em> (Ritter-Zahony, 1911) in the southern Benguela during spring 1987, with notes on seasonal variability of feeding ecology

    Item type: Journal Article • Journal: South African Journal of Marine Science
    The feeding biology and the vertical migration of Sagitta friderici were examined over 24 h at two stations in the southern Benguela during spring (October) 1987. Together with studies conducted during summer (February 1991) and winter (May 1984), they serve...
  9. Some observations on the pelagic decapod <em>Pasiphaea semispinosa</em> Holthuis 1951 in the Benguela upwelling system

    Some observations on the pelagic decapod <em>Pasiphaea semispinosa</em> Holthuis 1951 in the Benguela upwelling system

    Item type: Journal Article • Journal: South African Journal of Marine Science
    Information on vertical and horizontal distribution patterns, abundance and morphology of the decapod Pasiphaea semispinosa in the Benguela upwelling system is presented. P. semispinosa is the dominant pelagic decapod in the system, occurring between 19 and 32°S along the mid...
  10. Observations on euphausiid assemblages of the south coast of South Africa

    Observations on euphausiid assemblages of the south coast of South Africa

    Item type: Journal Article • Journal: South African Journal of Marine Science
    A total of 24 species of euphausiid was collected during a survey along the South African south coast during January 1992. Communities over the Agulhas Bank were of low diversity and abundance and were dominated by Nyctiphanes capensis. Those at...