Articles by Author: J Adams

Search results for J Adams

We found 47 results for you
  1. The function of the hygroscopic awn of <em>Themeda triandra</em> <sup>1</sup>

    Item type: Journal Article • Journal: Journal of the Grassland Society of Southern Africa
    The hygroscopic awn of species such as Themeda triandra is widely believed to be a device ensuring the early burial of its seed. This belief has been extensively tested and no tendency for such self‐burial has been found. It has...
  2. Monitoring of seabirds in the Benguela upwelling system: can seabirds be used as indicators and predictors of change in the marine environment?

    Monitoring of seabirds in the Benguela upwelling system: can seabirds be used as indicators and predictors of change in the marine environment?

    Item type: Journal Article • Journal: South African Journal of Marine Science
    Historical and contemporary data on Benguela seabirds assumed to be responsive to changes in food availability are reviewed as potential indicators and predictors of change in the ecosystem. Cyclic variations in the annual yields of seabird products evident at decadal...
  3. Trends in pelagic fish populations of the Saldanha Bay region, southern Benguela upwelling system, 1980–1990: a predator's perspective

    Trends in pelagic fish populations of the Saldanha Bay region, southern Benguela upwelling system, 1980–1990: a predator's perspective

    Item type: Journal Article • Journal: South African Journal of Marine Science
    Changes in monthly and annual prey species composition of African penguins Spheniscus demersus are described from 1 454 stomach samples collected from two breeding islands in the Saldanha Bay region of the southern Benguela upwelling system between 1980 and 1990...
  4. Foraging effort and prey choice in Cape gannets

    Foraging effort and prey choice in Cape gannets

    Item type: Journal Article • Journal: South African Journal of Marine Science
    In order to test the hypothesis that sardine Sardinops sagax are the preferred prey of Cape gannets Morus capensis, the link between foraging effort and prey choice was evaluated by simultaneously monitoring the activity and the diet of adult birds...
  5. REVIEW

    REVIEW

    Item type: Journal Article • Journal: Ostrich: Journal of African Ornithology
  6. Disturbance of incubating African Black Oystercatchers: is heating of exposed eggs a problem?

    Disturbance of incubating African Black Oystercatchers: is heating of exposed eggs a problem?

    Item type: Journal Article • Journal: Ostrich: Journal of African Ornithology
    Adams, N.J., Kerley, G.I.H. & Watson, J.J. 1999. Disturbance of incubating African Black Oystercatchers: is heating of exposed eggs a problem? Ostrich 70(3&4): 225–228.
  7. Influence of sward defoliation and soil disturbance on seedling emergence and survival in the Southern Tall Grassveld

    Influence of sward defoliation and soil disturbance on seedling emergence and survival in the Southern Tall Grassveld

    Item type: Journal Article • Journal: African Journal of Range & Forage Science
    Seedling emergence, survival and species composition were recorded on vegetation subjected to seven practicably feasible soil and defoliation treatments. Soil disturbance, with defoliation removal, produced the greatest number of emergents; these also had the best survivorship compared to other treatments...
  8. Reforming communal rangeland policy in southern Africa: challenges, dilemmas and opportunities

    Reforming communal rangeland policy in southern Africa: challenges, dilemmas and opportunities

    Item type: Journal Article • Journal: African Journal of Range & Forage Science
    In the savanna rangelands of southern Africa, the debate about land reform tends to be about the redistribution of formerly freehold ranches and fencing-off the rangeland commons into ranches for better-off African farmers. The position of those who favour privatisation...
  9. Towards reduced herbicide use in forest vegetation management

    Towards reduced herbicide use in forest vegetation management

    Item type: Journal Article • Journal: The Southern African Forestry Journal
    Mechanical, manual, thermal, biological and chemical methods of managing forest vegetation have, to a large extent, been developed independently. The effectiveness and relatively low cost of chemical herbicides, however, have led to systems of vegetation management that rely on their...