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The distribution and relative abundance of stream fishes in the upper Manyame River, Zimbabwe, in relation to land use, pollution and exotic predators
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: B Gratwicke --- Department of Biological Sciences, Zimbabwe BE Marshall --- Department of Biological Sciences, Zimbabwe T Nhiwatiwa --- Department of Biological Sciences, ZimbabweA survey of the upper Manyame River catchment, middle Zambezi system, Zimbabwe, yielded a total of 22 fish species from 48 stations. The most widespread species (present at >20 stations) were Marcusenius macrolepidotus, Barbus paludinosus, Labeo cylindricus, Clarias gariepinus and... -
The effect of largemouth bass Micropterus salmoides on aquatic macro-invertebrate communities in the Wit River, Eastern Cape, South Africa
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: PSR Weyl --- Department of Zoology and Entomology, South Africa FC de Moor --- Department of Zoology and Entomology, South Africa MP Hill --- Department of Zoology and Entomology, South Africa OLF Weyl --- , South AfricaFish predation is one of the driving forces of freshwater invertebrate community structures, with alien predators having a pronounced effect. A quantitative assessment of aquatic invertebrates in the Wit River, Sundays River catchment, Eastern Cape, South Africa, was undertaken to... -
Ecosystem considerations of the KwaZulu-Natal sardine run
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: L Hutchings --- Oceans and Coasts, Department of Environmental Affairs, South Africa T Morris --- Bayworld, Port Elizabeth Museum, South Africa CD van der Lingen --- Marine Research Institute, South Africa SJ Lamberth --- Branch Fisheries, Department of Agriculture, South Africa AD Connell --- , South Africa S Taljaard --- , South Africa L van Niekerk --- , South AfricaThe annual winter sardine run along the South African east coast impacts the KwaZulu-Natal (KZN) coastal system in a variety of ways. These include ecological impacts, such as enrichment of a largely oligotrophic environment, competition between migrant sardine Sardinops sagax,... -
The effect of fish predation on benthic macroinvertebrates in a seasonal stream in north-western Zimbabwe
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: Albert Chakona Brian Marshall Luc BrendonckThe cumulative impact of the entire fish assemblage on benthic macroinvertebrate assemblages was investigated over four months in a removal experiment in isolated pools that persist through the dry season, in an intermittent stream in north-western Zimbabwe. Macroinvertebrate taxonomic richness... -
Do inter-colony differences in Cape fur seal foraging behaviour reflect large-scale changes in the northern Benguela ecosystem?
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: M Skern-Mauritzen --- , Norway SP Kirkman --- Animal Demography Unit, Department of Zoology, South Africa E Olsen --- , Norway A Bjørge --- , Norway L Drapeau --- , France MA Meÿer --- Department of Environmental Affairs, South Africa J-P Roux --- Ministry of Fisheries and Marine Resources, Namibia S Swanson --- Department of Environmental Affairs, South Africa WH Oosthuizen --- Department of Environmental Affairs, South AfricaThe northern Benguela ecosystem adjoining Namibia has undergone considerable changes in recent decades, with reductions and northwards shifts of key prey species that have had severe implications for marine top predator populations. We investigated how such environmental variability may impact... -
Food abundance explains the breeding season of a tropical shorebird, the Crab Plover Dromas ardeola
Item type: Journal Article • Journal: Ostrich: Journal of African Ornithology • Authors: Giuseppe De Marchi --- Dipartimento di Scienze della Terra e dell'Ambiente, Italy Giorgio Chiozzi --- Museo Civico di Storia Naturale, Italy Dawit Semere --- Research Division, Eritrea Yohannes Mebrahtu --- Research Division, Eritrea Farhad Hosseini Tayefeh --- Department of the Environment Provincial Office, Iran Mohammed Almalki --- Department of Biology, College of Science, Kingdom of Saudi Arabia Mauro Fasola --- Dipartimento di Scienze della Terra e dell'Ambiente, ItalyThe timing of breeding in birds is a life-history trait that generally depends on food availability, but other factors may play a role, particularly in tropical areas where food availability is less seasonal than in temperate or polar areas. We... -
Trophic relationships of hake (Merluccius capensis and M. paradoxus) and sharks (Centrophorus squamosus, Deania calcea and D. profundorum) in the Northern (Namibia) Benguela Current region
Item type: Journal Article • Journal: African Zoology • Authors: Johannes A Iitembu --- Department of Fisheries and Aquatic Sciences, Namibia Nicole B Richoux --- Department of Zoology and Entomology, South AfricaThe trophic relationships of two hake species (Merluccius capensis and M. paradoxus) and three shark species (Centrophorus squamosus, Deania calcea and D. profundorum) were investigated using nitrogen and carbon stable isotope signatures (δ15N and δ13C) of their muscle tissues. The... -
Macroinvertebrate communities associated with duckweed (Lemnaceae) in two Eastern Cape rivers, South Africa
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: PC Muskett --- Department of Zoology and Entomology, South Africa JM Hill --- Department of Zoology and Entomology, South Africa PSR Weyl --- Department of Zoology and Entomology, South AfricaThe functional feeding groups and diversity of macroinvertebrate communities associated with duckweed mats in the New Years River (two sites) and Bloukrans River (two sites), Eastern Cape province, South Africa, were assessed. Duckweed (Lemnaceae) is a ubiquitous family of floating... -
Identification of land predators of African Penguins Spheniscus demersus through post-mortem examination
Item type: Journal Article • Journal: Ostrich: Journal of African Ornithology • Authors: Ralph ET Vanstreels --- Marine Apex Predator Research Unit, Institute for Coastal and Marine Research, South Africa Nola J Parsons --- Southern African Foundation for the Conservation of Coastal Birds, South Africa Cuan McGeorge --- Stony Point Nature Reserve, South Africa Renata Hurtado --- Southern African Foundation for the Conservation of Coastal Birds, South Africa Katrin Ludynia --- Southern African Foundation for the Conservation of Coastal Birds, South Africa Lauren Waller --- Southern African Foundation for the Conservation of Coastal Birds, South Africa Monique Ruthenberg --- Hottentots Holland Nature Reserve, South Africa Arne Purves --- Environmental Management Department, Transport and Urban Development Authority, South Africa Lorien Pichegru --- Marine Apex Predator Research Unit, Institute for Coastal and Marine Research, South Africa Pierre A Pistorius --- Marine Apex Predator Research Unit, Institute for Coastal and Marine Research, South AfricaThe African Penguin Spheniscus demersus is an endangered seabird endemic to southern Africa, and killing sprees by terrestrial predators have been one of the main threats for its mainland colonies. The methods employed to manage predators may differ depending on... -
When the flathead mullet left St Lucia
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: AK Whitfield --- , South AfricaThe St Lucia estuarine system on the east coast of South Africa is a declared World Heritage Site and Ramsar Site of International Importance. A major ecological feature of St Lucia during the last century was the annual spawning migration... -
Fear at the top: killer whale predation drives white shark absence at South Africa’s largest aggregation site
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: AV Towner --- , South Africa RGA Watson --- , South Africa AA Kock --- , South Africa Y Papastamatiou --- , United States M Sturup --- , South Africa E Gennari --- , South Africa K Baker --- , South Africa T Booth --- , South Africa M Dicken --- , South Africa W Chivell --- , South Africa S Elwen --- , South Africa T Kaschke --- , South Africa D Edwards --- , South Africa MJ Smale --- , South AfricaRisk-induced fear effects exerted by top predators are pervasive in terrestrial and marine systems, with lasting impacts on ecosystem structure and function. The loss of top predators can disrupt ecosystems and trigger trophic cascades, but the introduction of novel apex... -
New records and a notable observation of potentially predator-avoiding amplectic behaviour in Boophis erythrodactylus from Madagascar
Item type: Journal Article • Journal: African Journal of Herpetology • Authors: Robin Kurian Abraham --- Biodiversity Institute and Department of Ecology and Evolutionary Biology, University of Kansas, United States Carl Richard Hutter --- Biodiversity Institute and Department of Ecology and Evolutionary Biology, University of Kansas, United StatesThe Red-fingered Bright-eyed Frog Boophis erythrodactylus is an endemic, range-restricted arboreal frog found only in the eastern rainforests of Madagascar. We report new localities for this species, along with locality records for its sister species B. tasymena, including localities where... -
Predation on chameleons in Madagascar: a review
Item type: Journal Article • Journal: African Journal of Herpetology • Authors: Richard K. B. Jenkins --- School of Biological Sciences, University of Aberdeen, UK Jeanneney Rabearivony --- The Peregrine Fund, Madagascar Hajanirina Rakotomanana --- University of Antananarivo, MadagascarWe reviewed the diet of nocturnal and diurnal chameleon predators on Madagascar from the available literature and identified 28 species. Diurnal raptors were the main predators of chameleons, although the literature was biased towards birds and probably underestimated predation by... -
Distribution and site fidelity of four endemic catshark species in Walker Bay, South Africa
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: TL Johnson --- , South Africa JC de Bresser --- , South Africa E Cottrant --- , South Africa NJ Drobniewska --- , South Africa TG Paulet --- , South Africa LG Underhill --- University of Cape Town, South AfricaCatsharks (family Scyliorhinidae) and the recently reclassified deepwater catsharks (family Pentanchidae) are two of the largest families of elasmobranchs and include species that function as important mesopredators in almost all marine ecosystems. This study focuses on four species endemic to...