... Charles L. Griffiths, Tamara B. Robinson, and Angela Mead ... Invest Rep Div Sea Fish S Afr 2... more ... Charles L. Griffiths, Tamara B. Robinson, and Angela Mead ... Invest Rep Div Sea Fish S Afr 20:84102 Laird MC, Griffiths CL (2008) Present distribution and abundance of the ... Linnean Society, London, 241 pp McQuaid CD (1996) Biology of the gastropod family Littorinidae. II. ...
Some 33 marine crustaceans are currently known or suspected to have been introduced to South Afri... more Some 33 marine crustaceans are currently known or suspected to have been introduced to South Africa, with additional species regularly being discovered. The current list, including cryptogenic forms, comprises two barnacles, one copepod, 11 isopods, 17 amphipods and two crabs. We tabulate these species and examine their temporal patterns of discovery and current spatial distributions. The earliest introductions are thought to have arrived in dry ballast, or on wooden vessels, either boring into the wood itself, or as fouling. More recent introductions include species suspected to have arrived via ballast water, or along with farmed oysters. Most introduced crustaceans are confined to the few harbours and sheltered sites along this linear and wave-exposed coastline. Only two are known to cause significant ecological or economic impacts. The Pacific barnacle Balanus glandula has invaded over 400 km of open coast and altered community structure there, while the European shore crab Carcinus maenas has caused significant ecological disruption in the limited sites where it is now abundant. Future risks include the almost inevitable spread of C. maenas to additional sheltered sites, and introductions of additional species, especially via ballast water. Ballast water treatment and replacement of imported oyster spat by locally-cultured stock are among measures recommended to limit further introductions.
... Additionally, because ballast water is usually loaded in shallow, often turbid port areas, si... more ... Additionally, because ballast water is usually loaded in shallow, often turbid port areas, significant amounts of sediment can be loaded along with the water. ... There has also been less survey work on the east coast than in the west. ... Hewitt, CL, Gollasch, S. & Minchin, D. 2009. ...
No geographcally or taxonomically comprehensive census of marine alien species has ever been unde... more No geographcally or taxonomically comprehensive census of marine alien species has ever been undertaken in South Africa and the state of knowledge of the taxonomy of many marine invertebrate groups remains poor in this region (Gibbons 1999), compromising the ability to detect introduced species. Given these constraints, 22 confirmed extant marine aliens, plus 18 cryptogenic species, have been recorded from South African waters to date, with one additional species recently found in on-land mariculture facilities (Simon and Booth, in press). The true number of introduced species may well exceed these estimates by several times (see also Chap. 2, Carlton). All 22 of the marine alien species reported from the wild support well-established populations, but the majority of these remain restricted to the few sheltered bays, estuaries and harbours on this wave-exposed coastline. Interestingly, only three species are known to have become invasive (defined here as having spread significantly beyond their points of origin). These are the Mediterranean mussel Mytilus galloprovincialis, the European green crab Carcinus maenas(Griffiths et al. 1992; Robinson et al. 2005a) and the recently detected barnacle Balanus glandula(Laird and Griffiths, 2008). A list of species known to be introduced to the region, and which presently support populations is given in Table 23.1. Sites mentioned in this chapter are shown in Fig. 23.1. The various established species are discussed by taxonomic group below.
... Charles L. Griffiths, Tamara B. Robinson, and Angela Mead ... Invest Rep Div Sea Fish S Afr 2... more ... Charles L. Griffiths, Tamara B. Robinson, and Angela Mead ... Invest Rep Div Sea Fish S Afr 20:84102 Laird MC, Griffiths CL (2008) Present distribution and abundance of the ... Linnean Society, London, 241 pp McQuaid CD (1996) Biology of the gastropod family Littorinidae. II. ...
Some 33 marine crustaceans are currently known or suspected to have been introduced to South Afri... more Some 33 marine crustaceans are currently known or suspected to have been introduced to South Africa, with additional species regularly being discovered. The current list, including cryptogenic forms, comprises two barnacles, one copepod, 11 isopods, 17 amphipods and two crabs. We tabulate these species and examine their temporal patterns of discovery and current spatial distributions. The earliest introductions are thought to have arrived in dry ballast, or on wooden vessels, either boring into the wood itself, or as fouling. More recent introductions include species suspected to have arrived via ballast water, or along with farmed oysters. Most introduced crustaceans are confined to the few harbours and sheltered sites along this linear and wave-exposed coastline. Only two are known to cause significant ecological or economic impacts. The Pacific barnacle Balanus glandula has invaded over 400 km of open coast and altered community structure there, while the European shore crab Carcinus maenas has caused significant ecological disruption in the limited sites where it is now abundant. Future risks include the almost inevitable spread of C. maenas to additional sheltered sites, and introductions of additional species, especially via ballast water. Ballast water treatment and replacement of imported oyster spat by locally-cultured stock are among measures recommended to limit further introductions.
... Additionally, because ballast water is usually loaded in shallow, often turbid port areas, si... more ... Additionally, because ballast water is usually loaded in shallow, often turbid port areas, significant amounts of sediment can be loaded along with the water. ... There has also been less survey work on the east coast than in the west. ... Hewitt, CL, Gollasch, S. & Minchin, D. 2009. ...
No geographcally or taxonomically comprehensive census of marine alien species has ever been unde... more No geographcally or taxonomically comprehensive census of marine alien species has ever been undertaken in South Africa and the state of knowledge of the taxonomy of many marine invertebrate groups remains poor in this region (Gibbons 1999), compromising the ability to detect introduced species. Given these constraints, 22 confirmed extant marine aliens, plus 18 cryptogenic species, have been recorded from South African waters to date, with one additional species recently found in on-land mariculture facilities (Simon and Booth, in press). The true number of introduced species may well exceed these estimates by several times (see also Chap. 2, Carlton). All 22 of the marine alien species reported from the wild support well-established populations, but the majority of these remain restricted to the few sheltered bays, estuaries and harbours on this wave-exposed coastline. Interestingly, only three species are known to have become invasive (defined here as having spread significantly beyond their points of origin). These are the Mediterranean mussel Mytilus galloprovincialis, the European green crab Carcinus maenas(Griffiths et al. 1992; Robinson et al. 2005a) and the recently detected barnacle Balanus glandula(Laird and Griffiths, 2008). A list of species known to be introduced to the region, and which presently support populations is given in Table 23.1. Sites mentioned in this chapter are shown in Fig. 23.1. The various established species are discussed by taxonomic group below.
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