Browsing by Author "Walters, Michele"

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    The implications of the reclassification of South African wildlife species as farm animals
    (ASSAf, 2020-01-29) Somers, Michael J.; Walters, Michele; Measey, John; Turner, Andrew A.; Venter, Jan A.; Nel, Lizanne; Kerley, Graham I. H.; Taylor, W. Andrew; Moodley, Yoshan; Strauss, W. Maartin
    The Government Gazette No. 42464 dated 17 May 20191 amended Table 7 of the Animal Improvement Act (Act no. 62 of 1998), which lists breeds of animals, to include at least 32 new wild animal species, including 24 indigenous mammals. The list includes threatened and rare species such as cheetah, white and black rhinoceros, and suni. Some alien species such as lechwe, various deer species and rabbits are also included. The cornerstone of the original Act is ‘To provide for the breeding, identification and utilisation of genetically superior animals to improve the production and performance of animals in the interest of the Republic; and to provide for matters connected therewith.’ By declaring these wild animals as landrace breeds (in Table 7 of the regulations), the Act implies that they are locally developed breeds. The Act typically provides for landrace breeds to be bred and ‘genetically improved’ to obtain superior domesticated animals with enhanced production and performance. Similarly, provision is made for the Breeders Association to lay claim to the breed and to establish specific breed standards for animals to be included in stud books. Animals declared as landrace breeds can also be used for genetic manipulation, embryo harvesting, in-vitro fertilisation and embryo transfers. As indigenous species of wildlife are included in the recent amendment to the Act, the amendment is flawed. Here we point out numerous concerns in the new legislation, including the process of consultation, and argue that the law will not improve the genetics of the species mentioned but will have considerable negative genetic consequences and pose ecological and economic risks. We also suggest that this new law is in direct conflict with other biodiversity laws in South Africa.
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    Post-dispersal fate of Acacia seeds in an African savanna
    (Southern African Wildlife Management Association (SAWMA), 2005-10) Walters, Michele; Milton, Suzanne J.; Somers, Michael J.; Midgley, Jeremy J.
    African Acacia species are often major contributors to the progressive increase in the woody component of savannas, a phenomenon commonly referred to as bush encroachment. In Hluhluwe-iMfolozi Park, the numbers of adult Acacia nilotica (L.) Willd. Ex Del. subsp. kraussiana(Benth.) Brenan trees per hectare far exceed those of A. karroo Hayne adults. The relative dominance is reversed in the juvenile stage with A. karroo outnumbering A. nilotica threefold outside closed woodlands. We experimentally investigated the effects of location, structural habitat type, species, predator type and rodent presence on the level of post-dispersal seed predation in an attempt to explain species dominance in Hluhluwe-iMfolozi Park. Post-dispersal predation of A. karroo seeds (21.8%) was higher than that of A. nilotica (12.7%). Predation levels depended on site, structural habitat type, level of protection from different predator types and rodent presence/absence. There was more rodent predation in tall grass areas (26.0%) than grazing lawn (10.7%) or canopy areas (15.2%), and most seeds (19.7%) were lost from unprotected control groups. Rodent presence was a significant factor in a model aiming to determine reasons for unexplained seed disappearance. Post-dispersal predation of seeds could not account for the differences in success between A. karroo and A. nilotica in Hluhluwe-iMfolozi Park.
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    Seed ecology as a determinant of population structure in some Southern African Savanna Acacia species
    (Stellenbosch : Stellenbosch University, 2002-12) Walters, Michele; Milton, S. J.; Midgley, J. J.; Stellenbosch University. Faculty of AgriSciences. Dept. of Agricultural Economics.
    ENGLISH ABSTRACT: African Acacia species are often major contributors to the progressive increase in the woody component of savannas, a phenomenon commonly referred to as bush encroachment. In Hluhluwe- Umfolozi Park, the numbers of adult Acacia nilotica (L.) Willd. Ex Del. trees per hectare far exceed (by III) that of A. karroo Hayne adults. The relative dominance is reversed in the juvenile stage with A. karroo (725 ha') outnumbering A. nilotica (225 ha-I) threefold outside closed woodlands. African acacias produce large quantities of seed and may have large soil-stored seed banks. They suffer pre-dispersal predation by bruchid beetles and may be either wind or animal dispersed. Once dispersed they are vulnerable to post-dispersal attack. This study tested several hypotheses regarding various aspects of seed ecology of A. karroo and A. nilotica. The null hypothesis that seed ecology does not contribute to the success of A. karroo over A. nilotica, was tested. Acacia karroo trees were smaller (mean basal diameter: 7.8 cm) than A. ni/otica trees (mean basal diameter: 18.5 cm) on average, but produced more seeds (A. karroo mean: 1628; A. nilotica mean: 992) for a given basal diameter size class. It was found that A. karroo showed less bruchid infestation (mean: 1.36-3.81%) than A. nilotica (mean: 14.67-86.70%) at all stages of pod development with a proportion of A. karroo seeds (7.1 %) being able to germinate after bruchid attack. Bruchid attack rendered A. ni/otica seeds unviable. There was no difference between the two species with regards to the soil-stored seed bank and the viability of seeds found in the soil. Acacia karroo showed higher germination levels (5.1%) and better establishment (4.9%) than A. nilotica (1.5% and 0.4% respectively). On average, there was no difference in germination levels between burnt and unbumt seeds, but there was a significant difference in germination of burnt seeds in both burnt (4.5%) and unbumt (2.5%) sites and unbumt seeds in both burnt (2.8%) and unbumt (4.9%) sites when considered separately. Post-dispersal predation of A. karroo seeds (21.8%) was higher than that of A. nilotica (12.7%). There was more rodent predation in tall grass areas (26.0%) than short grass (10.7%) or canopy areas (15.2%), and most seeds were lost from unprotected control groups. Rodent presence was a significant factor in unexplained seed disappearance. The ability of A. karroo to germinate easily and the low levels of beetle predation experienced by this species seemed to be its main advantage over A. nilotica as an encroaching species in Hluhluwe-Umfolozi Park.
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    Taxonomic research in South Africa : the state of the discipline
    (Academy of Science of South Africa, 2008) Smith, Gideon F.; Buys, Matt; Walters, Michele; Herbert, Dai; Hamer, Michelle
    The need for taxonomy is imperative as we cannot protect organisms that are not known and which remain unidentified and uncharacterised, thereby limiting our capacity to understand them and to assess the influence of environmental change and other alterations in their condition. There is currently insufficient taxonomic capacity to keep abreast of the rate of new discoveries - our museums and herbaria already contain numerous unnamed species that await description. We outline the steps that our taxonomists have taken to promote their work - through conferences and the establishment of professional societies - and make the case for its enhanced support as an integral part of science policy.
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    Tourists' willingness to pay to view otters along the Wild Coast, South Africa
    (AOSIS, 2005) Dumalisile, Lihle; Walters, Michele; Somers, Michael; Nel, Jan
    This article reports on tourists’ willingness to pay to view Cape clawless otters Aonyx capensis along the Eastern Cape Wild Coast, South Africa. We collected data from a survey carried out using a structured, selfadministered questionnaire. We analyzed 67 completed questionnaires, of which 60 respondents (89.5%) indicated that they would be interested in viewing otters and would be prepared to pay an extra fee, over and above the normal entrance fees, for a trained guide to show them otters. The remaining 7 (10.4%) respondents indicated that they would reconsider and pay if this would create jobs for members of the local community. Most (98.4% and 91.8%) of the respondents also indicated that they would still pay even if there was only a 50% or 25% chance of seeing otters. Most of the respondents were willing to pay either less than R50.00 (ca US$8.00) or R50.00-R100.00 to view otters regardless of the chances of seeing them. We conclude from our results that otters do have the potential to increase ecotourism in the area, and also to contribute financially to the poverty stricken local Dwesa community.