Population structure and growth of polydorid polychaetes that infest cultured abalone Haliotis midae
- Simon, Carol A, Booth, Anthony J
- Authors: Simon, Carol A , Booth, Anthony J
- Date: 2010
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/125731 , vital:35812 , https://doi.10.2989/AJMS.2007.29.3.16.346
- Description: Polydorid polychaetes can infest cultured abalone thereby reducing productivity. In order to effectively control these pests, their reproductive biology must be understood. The population dynamics and reproduction of polydorids infesting abalone Haliotis midae from two farms in South Africa is described using a length-based, age-structured model. Shells were infested mainly by introduced Boccardia proboscidea. Polydora hoplura and Dipolydora capensis were also present but in numbers too few to identify factors influencing infestation. At both farms, B. proboscidea lived for a minimum of 12 months. Growth rate, size at maturity, maximum size, infestation intensity, recruitment, percentage of the population brooding and mortality appear to be affected by abalone feeding regime and water temperature, and these factors need to be considered in controlling infestation. Brooders and recruits were present throughout the year, but increased significantly during mid- to late winter/early spring when water temperature and day length increased. Treatment measures should therefore be implemented throughout the year but with increased effort when water temperature increases.
- Full Text:
- Date Issued: 2010
Population structure and growth of polydorid polychaetes that infest cultured abalone Haliotis midae
- Authors: Simon, Carol A , Booth, Anthony J
- Date: 2010
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/125731 , vital:35812 , https://doi.10.2989/AJMS.2007.29.3.16.346
- Description: Polydorid polychaetes can infest cultured abalone thereby reducing productivity. In order to effectively control these pests, their reproductive biology must be understood. The population dynamics and reproduction of polydorids infesting abalone Haliotis midae from two farms in South Africa is described using a length-based, age-structured model. Shells were infested mainly by introduced Boccardia proboscidea. Polydora hoplura and Dipolydora capensis were also present but in numbers too few to identify factors influencing infestation. At both farms, B. proboscidea lived for a minimum of 12 months. Growth rate, size at maturity, maximum size, infestation intensity, recruitment, percentage of the population brooding and mortality appear to be affected by abalone feeding regime and water temperature, and these factors need to be considered in controlling infestation. Brooders and recruits were present throughout the year, but increased significantly during mid- to late winter/early spring when water temperature and day length increased. Treatment measures should therefore be implemented throughout the year but with increased effort when water temperature increases.
- Full Text:
- Date Issued: 2010
The genus Boccardia (Polychaeta: Spionidae) associated with mollusc shells on the south coast of South Africa
- Simon, Carol A, Worsfold, T M, Lange, Louise, Sterley, Jessica A
- Authors: Simon, Carol A , Worsfold, T M , Lange, Louise , Sterley, Jessica A
- Date: 2010
- Language: English
- Type: text , Article
- Identifier: vital:6873 , http://hdl.handle.net/10962/d1011620 , http://dx.doi.org/10.1017/S0025315409990452
- Description: Three species of Boccardia (B. polybranchia, B. pseudonatrix and B. proboscidea) were associated with mollusc shells on the south and south-east coasts of South Africa. Boccardia polybranchia was widely distributed along the coast and falls within the known distribution range of this species. Comparisons with material from other, international, locations showed that some specimens have been misidentified. No characters could be found to characterize distinct species for different regions within the range of B. polybranchia, as currently recognized. Boccardia pseudonatrix was found only at the most eastern site, increasing its known distribution range. Boccardia proboscidea, a non-indigenous species, was found only on abalone farms and was most abundant in the west.
- Full Text:
- Date Issued: 2010
- Authors: Simon, Carol A , Worsfold, T M , Lange, Louise , Sterley, Jessica A
- Date: 2010
- Language: English
- Type: text , Article
- Identifier: vital:6873 , http://hdl.handle.net/10962/d1011620 , http://dx.doi.org/10.1017/S0025315409990452
- Description: Three species of Boccardia (B. polybranchia, B. pseudonatrix and B. proboscidea) were associated with mollusc shells on the south and south-east coasts of South Africa. Boccardia polybranchia was widely distributed along the coast and falls within the known distribution range of this species. Comparisons with material from other, international, locations showed that some specimens have been misidentified. No characters could be found to characterize distinct species for different regions within the range of B. polybranchia, as currently recognized. Boccardia pseudonatrix was found only at the most eastern site, increasing its known distribution range. Boccardia proboscidea, a non-indigenous species, was found only on abalone farms and was most abundant in the west.
- Full Text:
- Date Issued: 2010
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