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Alien and invasive fresh water Gastropoda in South Africa
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: CC Appleton --- , South AfricaTen species of freshwater gastropod have been introduced into South Africa, mostly through the aquarium trade. Two of these, Lymnaea columella (Lymnaeidae) and Physa acuta (Physidae), have been invasive in river systems across the country for many years, probably since... -
Benthic macrofauna community composition, abundance and distribution in the Tanzanian and Ugandan inshore and offshore waters of Lake Victoria
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: GW Ngupula --- , Tanzania R Kayanda --- , TanzaniaBenthic macroinvertebrate community composition was investigated in 2008 at 55 stations at various depths in the nearshore and offshore waters of Lake Victoria, in relation to dissolved oxygen, pH, temperature, chlorophyll a and conductivity. Macroinvertebrate abundance was higher in the... -
Population dynamics and ecology of freshwater gastropods in the highveld and lowveld regions of Zimbabwe, with emphasis on schistosome and amphistome intermediate hosts
Item type: Journal Article • Journal: African Zoology • Authors: G. Chingwena --- Department of Paraclinical Veterinary Studies, Zimbabwe S. Mukaratirwa --- Department of Paraclinical Veterinary Studies, Zimbabwe M. Chimbari --- University of Zimbabwe Lake Kariba Research Station, Zimbabwe T. K. Kristensen --- Danish Bilharziasis Laboratory, Denmark H. Madsen --- Danish Bilharziasis Laboratory, DenmarkFrom November 1998 to October 2000, patterns of distribution and seasonal population fluctuations of snails and factors influencing them were investigated in six dams and six streams in the highveld region, and in nine dams in the lowveld region of... -
Quantification of shell banding polymorphism in the East African tree snail Sitala jenynsi (Pulmonata: Ariophantidae)
Item type: Journal Article • Journal: African Zoology • Authors: Peter F. Kasigwa --- Department of Zoology, Tanzania John A. Allen --- School of Biological Sciences, University of Southampton, U.K.In eastern Africa, populations of the tree snail Sitala jenynsi are monomorphic, dimorphic or trimorphic for the width of the upper brown band on their shells.We measured the variation in the width of this band in several populations and analysed... -
Plant selection and grazing activity of the invasive snail Theba pisana in coastal Algoa Bay, South Africa
Item type: Journal Article • Journal: African Zoology • Authors: Sean van Elden --- DST–NRF Research Chair in Shallow Water Ecosystems, South Africa Nelson AF Miranda --- DST–NRF Research Chair in Shallow Water Ecosystems, South Africa Renzo Perissinotto --- DST–NRF Research Chair in Shallow Water Ecosystems, South Africa Janine B Adams --- Department of Botany, South AfricaThe land snail Theba pisana is a coastal species native to the Mediterranean but has been introduced to regions all over the world, including South Africa and Australia, where it is considered a pest. This study examines the diet of... -
Surfing in the sandy-beach whelk Bullia digitalis (Dillwyn)
Item type: Journal Article • Journal: African Zoology • Authors: A.C. Brown --- Department of Zoology, South AfricaA brief, integrated summary is presented of published and unpublished work relevant to surfing (swash riding) in intertidal members of the genus Bullia (Caenogastropoda), together with previously unreported investigations of the specific gravity of B. digitalis and the directional control... -
The effect of low-level kelp supplementation on digestive enzyme activity levels in cultured abalone Haliotis midae fed formulated feeds
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: A Nel --- Department of Ichthyology and Fisheries Science, South Africa BI Pletschke --- Department of Biochemistry and Microbiology, South Africa PJ Britz --- Department of Ichthyology and Fisheries Science, South AfricaPrevious studies have found that macroalgal inclusion in formulated diets for cultured abalone improves feed utilisation, and it was suggested that seaweed-associated bacteria supply enzymes that aid in the animal's digestion. In the present study, we hypothesised that kelp supplementation... -
Latitudinal gradients and poleward expansion of mangrove ecosystems in South Africa: 50 years after Macnae’s first assessment
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: N Peer --- DST/NRF Research Chair in Shallow-Water Ecosystems, South Africa A Rajkaran --- Department of Biodiversity and Conservation Biology, South Africa NAF Miranda --- DST/NRF Research Chair in Shallow-Water Ecosystems, South Africa RH Taylor --- Department of Hydrology, South Africa B Newman --- CSIR Natural Resources and the Environment, South Africa F Porri --- South African Institute for Aquatic Biodiversity (SAIAB), South Africa JL Raw --- Department of Botany, South Africa SP Mbense --- Department of Botany, South Africa JB Adams --- Department of Botany, South Africa R Perissinotto --- DST/NRF Research Chair in Shallow-Water Ecosystems, South AfricaMangroves occur in South African estuaries at their poleward distribution limits, extending into temperate habitats. In 1963, William Macnae published the first comprehensive assessment of mangrove swamps in South Africa and made firsthand observations of these mangrove ecosystems. This article... -
Investigating the effects of hypersalinity on the cardiac performance of the invasive gastropod Melanoides tuberculata (Müller, 1774)
Item type: Journal Article • Journal: African Zoology • Authors: TJ de Haas --- , South Africa LJ Connell --- , South Africa R Greenfield --- , South AfricaAnthropogenic activities have propelled the exploitation of natural environments, which along with climate change have resulted in salinity intrusion to freshwater ecosystems worldwide. To determine the extent the hypersalinity stressor has on freshwater ecosystems, physiological cardiac responses in the freshwater...