Articles by Author: D Robertson Andersson

Search results for D Robertson Andersson

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  1. Effects of wild and farm-grown macroalgae on the growth of juvenile South African abalone <em>Haliotis midae</em> Linnaeus

    Effects of wild and farm-grown macroalgae on the growth of juvenile South African abalone <em>Haliotis midae</em> Linnaeus

    Item type: Journal Article • Journal: African Journal of Aquatic Science
    The effect of various macroalgal diets on the growth of grow-out (>20 mm shell length) South African abalone Haliotis midae was investigated on a commercial abalone farm. The experiment consisted of four treatments: fresh kelp blades (Ecklonia maxima (Osbeck) Papenfuss)...
  2. Rapid assessment of tissue nitrogen in cultivated <em>Gracilaria gracilis</em> (Rhodophyta) and <em>Ulva lactuca</em> (Chlorophyta)

    Rapid assessment of tissue nitrogen in cultivated <em>Gracilaria gracilis</em> (Rhodophyta) and <em>Ulva lactuca</em> (Chlorophyta)

    Item type: Journal Article • Journal: African Journal of Aquatic Science
    Tissue nitrogen content and thallus colour were quantified using a rapid assessment method based on the Pantone® matt uncoated formula guide for raft-cultivated Gracilaria gracilis Steentoft, Irvine ef Farnham at Saldanha Bay and tank-cultivated Ulva lactuca Linnaeus at Jacobsbaai in...
  3. Changes in recreational shore anglers’ attitudes towards, and awareness of, linefish management along the KwaZulu-Natal coast, South Africa

    Changes in recreational shore anglers’ attitudes towards, and awareness of, linefish management along the KwaZulu-Natal coast, South Africa

    Item type: Journal Article • Journal: African Journal of Marine Science
    Management of recreational fisheries cannot be based on biological and stock assessment data alone but needs to include appropriate social aspects (including knowledge, attitudes and behaviour) of anglers within the fishery. The primary purpose of this study was to evaluate...
  4. Evapotranspirasie in drie plantgemeenskappe van ‘n <em>Rhigozum trichotomum</em> habitat te upington

    Item type: Journal Article • Journal: Journal of the Grassland Society of Southern Africa
    Evapotranspirasie in drie plantgemeenskappe van ‘n R. trichotomum habitat, naamlik, suiwer gras, suiwer R. trichotomum en ‘n gemengde stand van R. trichotomum en gras is gedurende die 1985–86 groeiseisoen bestudeer. Drie persele van elke plantgemeenskap is hidrologies geisoleer, besproei en...
  5. Die effek van plantpopulasie op die saadopbrengs van sonneblomkultivars

    Die effek van plantpopulasie op die saadopbrengs van sonneblomkultivars

    Item type: Journal Article • Journal: South African Journal of Plant and Soil
    'n Aantal sonneblombasters is vergelyk by drie plantpopulasies oor twee seisoene te Ermelo, Sandvet en Warmbad. Die doel was om die kompensasievermoë van kultivars te bepaal vir 'n swak stand. Onder laepotensiaal-toestande was die kultivar X plantpopulasie-interaksie nie beduidend nie,...
  6. Population estimates of the crab <em>Scylla serrata</em> (Forskål, 1755) (Decapoda: Portunidae) in two closed estuaries in Natal, South Africa, from mark-recapture methods

    Population estimates of the crab <em>Scylla serrata</em> (Forskål, 1755) (Decapoda: Portunidae) in two closed estuaries in Natal, South Africa, from mark-recapture methods

    Item type: Journal Article • Journal: South African Journal of Marine Science
    The abundance of Scylla serrata in two closed estuaries, the Mhlanga and the Msimbazi, in Natal, South Africa, was estimated by means of the mark-recapture models of Chao, Burnham and Overton, and Petersen. In view of the size-related variability in...
  7. Short Notes

    Short Notes

    Item type: Journal Article • Journal: Ostrich: Journal of African Ornithology
  8. SHORT NOTES

    SHORT NOTES

    Item type: Journal Article • Journal: Ostrich: Journal of African Ornithology
  9. ASPECTS OF THE POPULATION DYNAMICS OF CAPE VULTURES IN THE CAPE PROVINCE

    ASPECTS OF THE POPULATION DYNAMICS OF CAPE VULTURES IN THE CAPE PROVINCE

    Item type: Journal Article • Journal: Ostrich: Journal of African Ornithology
    Robertson, A. S. 1984. Aspects of the population dynamics of Cape Vultures in the Cape Province. Ostrich 55: 196–206.
  10. OBSERVATIONS ON THE POST-FLEDGING DEPENDENCE PERIOD OF CAPE VULTURES

    OBSERVATIONS ON THE POST-FLEDGING DEPENDENCE PERIOD OF CAPE VULTURES

    Item type: Journal Article • Journal: Ostrich: Journal of African Ornithology
    Robertson, A. S. 1985. Observations on the post-fledging dependence period of Cape Vultures. Ostrich 56: 58–66.