A preliminary survey of the estuaries on the south coast of South Africa, Cape St Blaize, Mossel Bay - Robberg Peninsula, Plettenberg Bay, with particular reference to the fish fauna
- James, Nicola Caroline, Harrison, T D
- Authors: James, Nicola Caroline , Harrison, T D
- Date: 2008
- Language: English
- Type: text , Article
- Identifier: vital:7141 , http://hdl.handle.net/10962/d1011834
- Description: The coastal river systems on the south coast of South Africa from Cape St Blaize to Robberg Peninsula were surveyed during October and November 1994. The ichthyofaunal and physico-chemical characteristics of each system are presented and their suitability as estuarine nursery areas is discussed. Five systems (Rooi, Meul, Grooteiland, Kranshoek and Crooks) are outlets of small coastal streams and probably provide little or no habitat for either resident estuarine or migrant marine fishes owing to their small size. Four systems (Maalgate, Gwaing, Skaapkop and Kaaimans) are located within deeply incised valleys and have a permanent connection with the sea. The amount of marginal and intertidal habitat available to fishes, however, is limited due to their morphology. Six systems (Hartenbos, Groot Brak, Touw, Swartvlei, Goukamma and Noetsie) are intermittently open to the sea. Although the Touw and Swartvlei are connected to coastal lake systems, flow within these estuaries is not sufficient to prevent the build up of a sand barrier at the mouth. The Hartenbos, Groot Brak, Goukamma, and Noetsie are also periodically closed by a sand bar. The construction of a dam in the lower catchment of the Groot Brak has affected the hydrology of the system. The two remaining estuaries (Klein Brak and Knysna) are permanently open. In addition to strong tidal currents, the fixing of the mouth of the Knysna Estuary between rocky headlands also serves to maintain a permanent connection with the sea. Mugilidae and Sparidae were represented by the greatest number of species, and also dominated catches numerically and by mass. The fish fauna of all the estuaries surveyed were dominated by the juveniles of estuarine-dependent marine species and estuarine-resident species were also well represented in catches. The estuaries surveyed provide a vital habitat for both marine migrant species and resident species, most of which are endemic to the region.
- Full Text:
- Date Issued: 2008
- Authors: James, Nicola Caroline , Harrison, T D
- Date: 2008
- Language: English
- Type: text , Article
- Identifier: vital:7141 , http://hdl.handle.net/10962/d1011834
- Description: The coastal river systems on the south coast of South Africa from Cape St Blaize to Robberg Peninsula were surveyed during October and November 1994. The ichthyofaunal and physico-chemical characteristics of each system are presented and their suitability as estuarine nursery areas is discussed. Five systems (Rooi, Meul, Grooteiland, Kranshoek and Crooks) are outlets of small coastal streams and probably provide little or no habitat for either resident estuarine or migrant marine fishes owing to their small size. Four systems (Maalgate, Gwaing, Skaapkop and Kaaimans) are located within deeply incised valleys and have a permanent connection with the sea. The amount of marginal and intertidal habitat available to fishes, however, is limited due to their morphology. Six systems (Hartenbos, Groot Brak, Touw, Swartvlei, Goukamma and Noetsie) are intermittently open to the sea. Although the Touw and Swartvlei are connected to coastal lake systems, flow within these estuaries is not sufficient to prevent the build up of a sand barrier at the mouth. The Hartenbos, Groot Brak, Goukamma, and Noetsie are also periodically closed by a sand bar. The construction of a dam in the lower catchment of the Groot Brak has affected the hydrology of the system. The two remaining estuaries (Klein Brak and Knysna) are permanently open. In addition to strong tidal currents, the fixing of the mouth of the Knysna Estuary between rocky headlands also serves to maintain a permanent connection with the sea. Mugilidae and Sparidae were represented by the greatest number of species, and also dominated catches numerically and by mass. The fish fauna of all the estuaries surveyed were dominated by the juveniles of estuarine-dependent marine species and estuarine-resident species were also well represented in catches. The estuaries surveyed provide a vital habitat for both marine migrant species and resident species, most of which are endemic to the region.
- Full Text:
- Date Issued: 2008
Global diversity of mayflies (Ephemeroptera, Insecta) in freshwater
- Barber-James, Helen M, Gattolliat, J-L, Sartori, Michel, Hubbard, Michael D
- Authors: Barber-James, Helen M , Gattolliat, J-L , Sartori, Michel , Hubbard, Michael D
- Date: 2008
- Language: English
- Type: text , Article
- Identifier: vital:6895 , http://hdl.handle.net/10962/d1011655
- Description: The extant global Ephemeroptera fauna is represented by over 3,000 described species in 42 families and more than 400 genera. The highest generic diversity occurs in the Neotropics, with a correspondingly high species diversity, while the Palaearctic has the lowest generic diversity, but a high species diversity. Such distribution patterns may relate to how long evolutionary processes have been carrying on in isolation in a bioregion. Over an extended period, there may be extinction of species, but evolution of more genera. Dramatic extinction events such as the K-T mass extinction have affected current mayfly diversity and distribution. Climatic history plays an important role in the rate of speciation in an area, with regions which have been climatically stable over long periods having fewer species per genus, when compared to regions subjected to climatic stresses, such as glaciation. A total of 13 families are endemic to specific bioregions, with eight among them being monospecific. Most of these have restricted distributions which may be the result of them being the relict of a previously more diverse, but presently almost completely extinct family, or may be the consequence of vicariance events, resulting from evolution due to long-term isolation.
- Full Text:
- Date Issued: 2008
- Authors: Barber-James, Helen M , Gattolliat, J-L , Sartori, Michel , Hubbard, Michael D
- Date: 2008
- Language: English
- Type: text , Article
- Identifier: vital:6895 , http://hdl.handle.net/10962/d1011655
- Description: The extant global Ephemeroptera fauna is represented by over 3,000 described species in 42 families and more than 400 genera. The highest generic diversity occurs in the Neotropics, with a correspondingly high species diversity, while the Palaearctic has the lowest generic diversity, but a high species diversity. Such distribution patterns may relate to how long evolutionary processes have been carrying on in isolation in a bioregion. Over an extended period, there may be extinction of species, but evolution of more genera. Dramatic extinction events such as the K-T mass extinction have affected current mayfly diversity and distribution. Climatic history plays an important role in the rate of speciation in an area, with regions which have been climatically stable over long periods having fewer species per genus, when compared to regions subjected to climatic stresses, such as glaciation. A total of 13 families are endemic to specific bioregions, with eight among them being monospecific. Most of these have restricted distributions which may be the result of them being the relict of a previously more diverse, but presently almost completely extinct family, or may be the consequence of vicariance events, resulting from evolution due to long-term isolation.
- Full Text:
- Date Issued: 2008
Impediments to the delivery of socioeconomic rights in South Africa
- Authors: Roodt, Monty J
- Date: 2008
- Language: English
- Type: Conference paper
- Identifier: vital:6318 , http://hdl.handle.net/10962/d1011315
- Description: [from the Introduction] The purpose of including Second and Third Generation (STG) rights in a constitution is to provide guidelines to lawmakers to formulate policy and to enable the courts to intervene where these policies are not being implemented satisfactorily. In theory these rights allow citizens to demand from the state access to basic needs, such as adequate land, housing, education, health care, nutrition, and social security. However, this inclusion of rights in the constitution often does not translate into action. The first reason for this is that Second and Third Generation rights may clash with First Generation rights. For example the right to private property may, and in South Africa does, contradict the need for land for the majority. The major problem is whether the policies flowing out of Second and Third Generation rights are pursued with enough vigour by governments, the private sector, primary groups and individuals to overcome this contradiction. In many countries in the world it is the poorest sections of the population, and as Mamdani (1996) pointed out, migrant non-citizens, that bear the brunt of administrative and bureaucratic bungling and neglect.
- Full Text:
- Date Issued: 2008
- Authors: Roodt, Monty J
- Date: 2008
- Language: English
- Type: Conference paper
- Identifier: vital:6318 , http://hdl.handle.net/10962/d1011315
- Description: [from the Introduction] The purpose of including Second and Third Generation (STG) rights in a constitution is to provide guidelines to lawmakers to formulate policy and to enable the courts to intervene where these policies are not being implemented satisfactorily. In theory these rights allow citizens to demand from the state access to basic needs, such as adequate land, housing, education, health care, nutrition, and social security. However, this inclusion of rights in the constitution often does not translate into action. The first reason for this is that Second and Third Generation rights may clash with First Generation rights. For example the right to private property may, and in South Africa does, contradict the need for land for the majority. The major problem is whether the policies flowing out of Second and Third Generation rights are pursued with enough vigour by governments, the private sector, primary groups and individuals to overcome this contradiction. In many countries in the world it is the poorest sections of the population, and as Mamdani (1996) pointed out, migrant non-citizens, that bear the brunt of administrative and bureaucratic bungling and neglect.
- Full Text:
- Date Issued: 2008
The Cultural Use of the Wild Olive Tree by the amaXhosa People in the Eastern Cape Province of South Africa:
- Cocks, Michelle L, Dold, Anthony P
- Authors: Cocks, Michelle L , Dold, Anthony P
- Date: 2008
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/141314 , vital:37961 , DOI: 10.1558/jsrnc.v2i3.292
- Description: The cultural meanings of harvested plants have for the most part been ignored in academic research on non-timber forest products (NTFPs) in southern Africa. Historically scientists have tended to ignore the complex relationships between nature and culture. Given the country's unique political and economic past and the current search for sustainable use of natural resources, a focus on the convergence of natural science and cultural diversity is important at this time. Empirical data on cultural practices is being collected in order to develop fresh and relevant insights into the complex relationships between culture and bítKÜversity. The purpose of this paper is to demonstrate that the concept of culture needs to be brought into our understanding of the role of NTFPs. We dtxrument the use and value of a specific tree, Olea europaea L. subsp. africana (Mill.) P,S. Green, called Umiicjuma in the Xhosa language, for cultural purposes, by both rural and urban households.
- Full Text:
- Date Issued: 2008
- Authors: Cocks, Michelle L , Dold, Anthony P
- Date: 2008
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/141314 , vital:37961 , DOI: 10.1558/jsrnc.v2i3.292
- Description: The cultural meanings of harvested plants have for the most part been ignored in academic research on non-timber forest products (NTFPs) in southern Africa. Historically scientists have tended to ignore the complex relationships between nature and culture. Given the country's unique political and economic past and the current search for sustainable use of natural resources, a focus on the convergence of natural science and cultural diversity is important at this time. Empirical data on cultural practices is being collected in order to develop fresh and relevant insights into the complex relationships between culture and bítKÜversity. The purpose of this paper is to demonstrate that the concept of culture needs to be brought into our understanding of the role of NTFPs. We dtxrument the use and value of a specific tree, Olea europaea L. subsp. africana (Mill.) P,S. Green, called Umiicjuma in the Xhosa language, for cultural purposes, by both rural and urban households.
- Full Text:
- Date Issued: 2008
The Late Glacial and Holocene avifauna of the island of St Helena, South Atlantic Ocean
- Authors: Lewis, Colin A
- Date: 2008
- Language: English
- Type: Article
- Identifier: vital:6702 , http://hdl.handle.net/10962/d1006738
- Description: Bird bones from unconsolidated sediments provide a record of the changing avifauna of St Helena from the Late Glacial, at ~ 14000BP, until the present. Changes in avifauna apparently reflect climatic and associated ecological conditions, as well as the effects of human occupation since the island was discovered in 1502. Introduced mammals decimated birds in the seventeenth century and seven endemic species are now extinct, while seven other species are locally extinct. At least nine species that now breed on St Helena have been introduced anthropogenically to the island since it was discovered. The failure to find evidence of native songbirds in the former woodlands of the interior of the island deserves explanation.
- Full Text:
- Date Issued: 2008
- Authors: Lewis, Colin A
- Date: 2008
- Language: English
- Type: Article
- Identifier: vital:6702 , http://hdl.handle.net/10962/d1006738
- Description: Bird bones from unconsolidated sediments provide a record of the changing avifauna of St Helena from the Late Glacial, at ~ 14000BP, until the present. Changes in avifauna apparently reflect climatic and associated ecological conditions, as well as the effects of human occupation since the island was discovered in 1502. Introduced mammals decimated birds in the seventeenth century and seven endemic species are now extinct, while seven other species are locally extinct. At least nine species that now breed on St Helena have been introduced anthropogenically to the island since it was discovered. The failure to find evidence of native songbirds in the former woodlands of the interior of the island deserves explanation.
- Full Text:
- Date Issued: 2008
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