Pub Date : 2022-01-02DOI: 10.1080/15627020.2022.2047104
Jessica Seath, C. Shackleton
Invasive alien species are regarded as the second greatest threat to biodiversity globally. Yet, at a local scale their effects may vary, underlying the requirement for more local-scale studies across taxa and settings. Here we consider the effects of an alien invasive tree (Acacia dealbata, 5–8 m tall) on avifaunal numbers, richness and diversity in A. dealbata patches of three sizes relative to adjacent montane grasslands. Analysis of historical aerial photographs showed that A. dealbata first occurred in the area in the late 1930s/early 1940s and has continued to spread, despite some efforts by the landowner to keep it in check. It now covers approximately 11% of the site. This has provided habitat for a number of bird species more characteristic of wooded vegetation types. The number, richness and diversity of birds were greater in A. dealbata patches than the adjacent grasslands of equivalent size. These measures increased with increasing patch size, but more rapidly for A. dealbata patches than grassland ones. Only six of the 48 species of birds recorded were common between the two vegetation types. The most common feeding guild in the A. dealbata patches was insectivores, whereas in the grasslands it was omnivores. Although the invasion of A. dealbata has added to the habitat diversity of the area, thereby facilitating increased avifaunal diversity, if it continues to spread, then the populations and perhaps richness of grassland birds are likely to be negatively affected.
{"title":"Comparative Avifaunal Richness and Diversity in Invasive Acacia dealbata Patches and Adjacent Montane Grasslands","authors":"Jessica Seath, C. Shackleton","doi":"10.1080/15627020.2022.2047104","DOIUrl":"https://doi.org/10.1080/15627020.2022.2047104","url":null,"abstract":"Invasive alien species are regarded as the second greatest threat to biodiversity globally. Yet, at a local scale their effects may vary, underlying the requirement for more local-scale studies across taxa and settings. Here we consider the effects of an alien invasive tree (Acacia dealbata, 5–8 m tall) on avifaunal numbers, richness and diversity in A. dealbata patches of three sizes relative to adjacent montane grasslands. Analysis of historical aerial photographs showed that A. dealbata first occurred in the area in the late 1930s/early 1940s and has continued to spread, despite some efforts by the landowner to keep it in check. It now covers approximately 11% of the site. This has provided habitat for a number of bird species more characteristic of wooded vegetation types. The number, richness and diversity of birds were greater in A. dealbata patches than the adjacent grasslands of equivalent size. These measures increased with increasing patch size, but more rapidly for A. dealbata patches than grassland ones. Only six of the 48 species of birds recorded were common between the two vegetation types. The most common feeding guild in the A. dealbata patches was insectivores, whereas in the grasslands it was omnivores. Although the invasion of A. dealbata has added to the habitat diversity of the area, thereby facilitating increased avifaunal diversity, if it continues to spread, then the populations and perhaps richness of grassland birds are likely to be negatively affected.","PeriodicalId":55548,"journal":{"name":"African Zoology","volume":"57 1","pages":"12 - 19"},"PeriodicalIF":1.1,"publicationDate":"2022-01-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49023643","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-01-02DOI: 10.1080/15627020.2022.2046155
S. Penny, M. Withey, Rachel L. White, D. Scott, Lynne M. MacTavish, A. Pernetta
In many social species physical attributes correlate with dominance rankings and influence the outcomes of dyadic interactions. We investigated the processes that affect white rhinoceros' social behaviour in response to a reduction in horn size asymmetries within a group of subadult individuals. We monitored agonistic social interactions and the orderliness of social rankings between six free ranging rhinoceroses before and after they underwent a second dehorning procedure. We used a modified version of Landau's h′ to measure linearity, a score of steepness to measure power asymmetry, and a measure of triangle transitivity to assess relationships in the presence of null dyads. Agonistic social interactions were significantly greater after the monitored dehorning procedure. Hierarchies possessed significant steepness and transitivity prior to the procedure, but not after. Linearity was non-significant and rank order did not correspond with changes in horn size or age. Our results provide the first evidence of a dominance hierarchy among free-ranging white rhinoceroses outside of reproductive competition, but indicate that physical attributes alone do not explain social rankings. Rhinoceroses transitioned to a more egalitarian dominance structure than a despotic one after the procedure, but dominance ranks were only weakly differentiated within the group. Although a reduction in horn asymmetries may increase agonistic behaviours via psychosocial or behavioural changes, drier climatic conditions cannot be ruled out as the causative factor and because the subadult group stayed together, rather than dispersing, any increased fitness costs are likely to be minimal and outweighed by the benefits of group membership.
{"title":"Changes in Social Dominance in a Group of Subadult White Rhinoceroses (Ceratotherium simum) after Dehorning","authors":"S. Penny, M. Withey, Rachel L. White, D. Scott, Lynne M. MacTavish, A. Pernetta","doi":"10.1080/15627020.2022.2046155","DOIUrl":"https://doi.org/10.1080/15627020.2022.2046155","url":null,"abstract":"In many social species physical attributes correlate with dominance rankings and influence the outcomes of dyadic interactions. We investigated the processes that affect white rhinoceros' social behaviour in response to a reduction in horn size asymmetries within a group of subadult individuals. We monitored agonistic social interactions and the orderliness of social rankings between six free ranging rhinoceroses before and after they underwent a second dehorning procedure. We used a modified version of Landau's h′ to measure linearity, a score of steepness to measure power asymmetry, and a measure of triangle transitivity to assess relationships in the presence of null dyads. Agonistic social interactions were significantly greater after the monitored dehorning procedure. Hierarchies possessed significant steepness and transitivity prior to the procedure, but not after. Linearity was non-significant and rank order did not correspond with changes in horn size or age. Our results provide the first evidence of a dominance hierarchy among free-ranging white rhinoceroses outside of reproductive competition, but indicate that physical attributes alone do not explain social rankings. Rhinoceroses transitioned to a more egalitarian dominance structure than a despotic one after the procedure, but dominance ranks were only weakly differentiated within the group. Although a reduction in horn asymmetries may increase agonistic behaviours via psychosocial or behavioural changes, drier climatic conditions cannot be ruled out as the causative factor and because the subadult group stayed together, rather than dispersing, any increased fitness costs are likely to be minimal and outweighed by the benefits of group membership.","PeriodicalId":55548,"journal":{"name":"African Zoology","volume":"57 1","pages":"32 - 42"},"PeriodicalIF":1.1,"publicationDate":"2022-01-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45927146","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-01-02DOI: 10.1080/15627020.2022.2053883
G. Kerley, Sophie Monsarrat
Human activities have affected animals’ behaviour, distribution and population structure and this effect is predicted to increase in the future. Considerable effort is therefore being focussed on understanding and predicting such future changes in response to anthropogenic pressures, this to better conserve and restore populations and species. However, there is a risk that scientists and practitioners fail to recognise the extent of past human effects on biodiversity and use the situation they are familiar with as a baseline and a measure against which to assess current or future biodiversity changes. This failure to recognise past changes is known as the shifting baseline syndrome (Pauly 1995). We propose that when models (descriptive, quantitative or conceptual) describing niche features, such as distribution, habitat use, dietary resources or behaviour, are developed using data collected in a system (communities, species or populations) that has already undergone shifted baselines, such models should be referred to as ‘shifted models’. Here we define such shifted models and demonstrate associated shortcomings, focusing on the particular example of shifted environmental niche models in a recently published study on African elephants Loxodonta africana (Dejene et al. 2021).
人类活动影响了动物的行为、分布和种群结构，预计这种影响将在未来增加。因此，相当多的努力集中在了解和预测这种未来变化以应对人为压力，以便更好地保护和恢复种群和物种。然而，有一种风险是科学家和实践者没有认识到过去人类对生物多样性影响的程度，并且没有使用他们所熟悉的情况作为基线和衡量来评估当前或未来的生物多样性变化。这种无法识别过去变化的现象被称为基线转移综合征(Pauly 1995)。我们建议，当描述生态位特征(如分布、栖息地利用、饮食资源或行为)的模型(描述性、定量或概念性)是利用一个系统(群落、物种或种群)中收集的数据开发的，这些数据已经经历了基线的转移，这样的模型应该被称为“转移模型”。在这里，我们定义了这种转移模型，并展示了相关的缺点，重点关注最近发表的一项关于非洲象Loxodonta africana的研究中转移环境生态位模型的具体例子(Dejene et al. 2021)。
{"title":"Shifted Models Cannot be Used for Predicting Responses of Biodiversity to Global Change: The African Elephant as an Example","authors":"G. Kerley, Sophie Monsarrat","doi":"10.1080/15627020.2022.2053883","DOIUrl":"https://doi.org/10.1080/15627020.2022.2053883","url":null,"abstract":"Human activities have affected animals’ behaviour, distribution and population structure and this effect is predicted to increase in the future. Considerable effort is therefore being focussed on understanding and predicting such future changes in response to anthropogenic pressures, this to better conserve and restore populations and species. However, there is a risk that scientists and practitioners fail to recognise the extent of past human effects on biodiversity and use the situation they are familiar with as a baseline and a measure against which to assess current or future biodiversity changes. This failure to recognise past changes is known as the shifting baseline syndrome (Pauly 1995). We propose that when models (descriptive, quantitative or conceptual) describing niche features, such as distribution, habitat use, dietary resources or behaviour, are developed using data collected in a system (communities, species or populations) that has already undergone shifted baselines, such models should be referred to as ‘shifted models’. Here we define such shifted models and demonstrate associated shortcomings, focusing on the particular example of shifted environmental niche models in a recently published study on African elephants Loxodonta africana (Dejene et al. 2021).","PeriodicalId":55548,"journal":{"name":"African Zoology","volume":"57 1","pages":"70 - 73"},"PeriodicalIF":1.1,"publicationDate":"2022-01-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47701922","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-01-02DOI: 10.1080/15627020.2022.2035254
R. Foster, A. Childs, B. Mann, W. Potts
The South African spearfishery targets a variety of data-deficient species, which are consequently poorly managed. This study aimed to describe the age and growth of one of these species, the Cape knifejaw, Oplegnathus conwayi, which is endemic to the southern and eastern coasts of South Africa. Monthly biological samples were collected through research spearfishing (n = 170) and augmented by recreational spearfishers' catches (n = 135). The results indicated that the O. conwayi population sex ratio was skewed towards males (1M:0.6F). The length- and age-frequency distributions were similar between sexes. Oplegnathus conwayi is a relatively slow-growing species, with a maximum-recorded age of 27 years. No significant differences were observed between male and female growth, with the overall population growth curve being best described as L(t) = 697.15(1 – e–0.06(t–6.30)). The slow growth observed in this species is characteristic of a species that is vulnerable to overexploitation, and accordingly a precautionary approach to future management is recommended.
{"title":"Age and Growth of the Cape Knifejaw Oplegnathus conwayi, an Endemic South African Teleost","authors":"R. Foster, A. Childs, B. Mann, W. Potts","doi":"10.1080/15627020.2022.2035254","DOIUrl":"https://doi.org/10.1080/15627020.2022.2035254","url":null,"abstract":"The South African spearfishery targets a variety of data-deficient species, which are consequently poorly managed. This study aimed to describe the age and growth of one of these species, the Cape knifejaw, Oplegnathus conwayi, which is endemic to the southern and eastern coasts of South Africa. Monthly biological samples were collected through research spearfishing (n = 170) and augmented by recreational spearfishers' catches (n = 135). The results indicated that the O. conwayi population sex ratio was skewed towards males (1M:0.6F). The length- and age-frequency distributions were similar between sexes. Oplegnathus conwayi is a relatively slow-growing species, with a maximum-recorded age of 27 years. No significant differences were observed between male and female growth, with the overall population growth curve being best described as L(t) = 697.15(1 – e–0.06(t–6.30)). The slow growth observed in this species is characteristic of a species that is vulnerable to overexploitation, and accordingly a precautionary approach to future management is recommended.","PeriodicalId":55548,"journal":{"name":"African Zoology","volume":"57 1","pages":"1 - 11"},"PeriodicalIF":1.1,"publicationDate":"2022-01-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44849823","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-01-02DOI: 10.1080/15627020.2022.2063424
A. McKechnie, N. Mzilikazi, D. Levesque, S. Welman
{"title":"In Memory of Barry Gordon Lovegrove","authors":"A. McKechnie, N. Mzilikazi, D. Levesque, S. Welman","doi":"10.1080/15627020.2022.2063424","DOIUrl":"https://doi.org/10.1080/15627020.2022.2063424","url":null,"abstract":"","PeriodicalId":55548,"journal":{"name":"African Zoology","volume":"57 1","pages":"iii - iv"},"PeriodicalIF":1.1,"publicationDate":"2022-01-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47635640","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-10-02DOI: 10.1080/15627020.2021.2000341
J. Gane, C. Downs, Benjamin Harris, Mark Brown
Increasing beach sediment loss from erosion and high levels of crab Ocypode spp. predation are threatening turtle nests and nesting habitat. The 900 m long beach on Cousine Island, Seychelles, supports a nesting population of approximately 70–130 hawksbill turtle Eretmochelys imbricata nests each season. Seasonal and storm-related erosion and accretion cycles on Cousine Island have the potential of destroying 50% or more of all turtle egg clutches on the island in a single nesting season. Observed crab predation rates had reached 90–100% in preferred nesting beach zones in previous years. This has resulted in intensive management measures to minimise turtle egg and nest losses. We investigated the distribution and population density of ghost crabs and the morphology of the beach across the different beach area zones and across the turtle-nesting season during 2014–2015. Crab burrow numbers varied between beach zone areas and across the season and were highest on the backshore. Crab density correlated negatively with available beach area, and we found that crab density increased in the presence of turtle nests. When examining beach dynamics, we found them to be cyclical and found the nesting beach prone to higher levels of erosion than accretion with significant changes in beach width throughout the season. The mean vertical beach elevation drop on Cousine Island was higher than what hawksbill turtles have been reported to prefer. We suggest the continuation of beach elevation monitoring and management to use the beach morphology data to assist with hawksbill turtle nest translocations to minimise nest losses and maximise hatchling recruitment success.
{"title":"Beach Profiling and Ghost Crab Densities on a Hawksbill Turtle Nesting Beach in the Seychelles","authors":"J. Gane, C. Downs, Benjamin Harris, Mark Brown","doi":"10.1080/15627020.2021.2000341","DOIUrl":"https://doi.org/10.1080/15627020.2021.2000341","url":null,"abstract":"Increasing beach sediment loss from erosion and high levels of crab Ocypode spp. predation are threatening turtle nests and nesting habitat. The 900 m long beach on Cousine Island, Seychelles, supports a nesting population of approximately 70–130 hawksbill turtle Eretmochelys imbricata nests each season. Seasonal and storm-related erosion and accretion cycles on Cousine Island have the potential of destroying 50% or more of all turtle egg clutches on the island in a single nesting season. Observed crab predation rates had reached 90–100% in preferred nesting beach zones in previous years. This has resulted in intensive management measures to minimise turtle egg and nest losses. We investigated the distribution and population density of ghost crabs and the morphology of the beach across the different beach area zones and across the turtle-nesting season during 2014–2015. Crab burrow numbers varied between beach zone areas and across the season and were highest on the backshore. Crab density correlated negatively with available beach area, and we found that crab density increased in the presence of turtle nests. When examining beach dynamics, we found them to be cyclical and found the nesting beach prone to higher levels of erosion than accretion with significant changes in beach width throughout the season. The mean vertical beach elevation drop on Cousine Island was higher than what hawksbill turtles have been reported to prefer. We suggest the continuation of beach elevation monitoring and management to use the beach morphology data to assist with hawksbill turtle nest translocations to minimise nest losses and maximise hatchling recruitment success.","PeriodicalId":55548,"journal":{"name":"African Zoology","volume":"56 1","pages":"264 - 272"},"PeriodicalIF":1.1,"publicationDate":"2021-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41749011","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-10-02DOI: 10.1080/15627020.2021.2011411
R. J. Power, Matthew S. Rogan, V. Naude
Although highly adaptable, leopards incur substantial mortality in human-modified landscapes and generally subsist at lower densities than in protected areas. Leopard populations are difficult to enumerate across any landscapes, though there have been strides to improve upon this, particularly in South Africa. This study aimed to determine the population density of leopards in the Magaliesberg mountain range of the North West province in 2015 and provided a longitudinal comparison of these camera-trapping sites. It appraises the efficacy of interventions aimed at improving the status quo of zero leopards found during a prior survey in 2011. Such interventions included a moratorium on sport hunting of the species, and the reintroduction of four individuals, two of each sex, into this area. Camera trapping over 10 months detected seven unique individuals, including one juvenile and six adults, consisting of four males and three females, half of which were previously reintroduced or progeny thereof. A Bayesian capture-recapture abundance model indicated a population of 5–7 individuals occurring within 1 480 km2 of available habitat, yielding a density estimate of 0.34–0.47 adult leopards per 100 km2, which is a relatively low estimate, likely due to population suppression from anthropogenic pressures surrounding the site (i.e., snaring). This study demonstrates that large carnivore populations can recolonise their former range via targeted interventions within topographical refugia.
{"title":"Mountain Refugia Limit Anthropogenic Suppression in a Re-Established Felid Population: The Case of the Magaliesberg Leopard Population in South Africa","authors":"R. J. Power, Matthew S. Rogan, V. Naude","doi":"10.1080/15627020.2021.2011411","DOIUrl":"https://doi.org/10.1080/15627020.2021.2011411","url":null,"abstract":"Although highly adaptable, leopards incur substantial mortality in human-modified landscapes and generally subsist at lower densities than in protected areas. Leopard populations are difficult to enumerate across any landscapes, though there have been strides to improve upon this, particularly in South Africa. This study aimed to determine the population density of leopards in the Magaliesberg mountain range of the North West province in 2015 and provided a longitudinal comparison of these camera-trapping sites. It appraises the efficacy of interventions aimed at improving the status quo of zero leopards found during a prior survey in 2011. Such interventions included a moratorium on sport hunting of the species, and the reintroduction of four individuals, two of each sex, into this area. Camera trapping over 10 months detected seven unique individuals, including one juvenile and six adults, consisting of four males and three females, half of which were previously reintroduced or progeny thereof. A Bayesian capture-recapture abundance model indicated a population of 5–7 individuals occurring within 1 480 km2 of available habitat, yielding a density estimate of 0.34–0.47 adult leopards per 100 km2, which is a relatively low estimate, likely due to population suppression from anthropogenic pressures surrounding the site (i.e., snaring). This study demonstrates that large carnivore populations can recolonise their former range via targeted interventions within topographical refugia.","PeriodicalId":55548,"journal":{"name":"African Zoology","volume":"56 1","pages":"292 - 302"},"PeriodicalIF":1.1,"publicationDate":"2021-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42658902","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-10-02DOI: 10.1080/15627020.2021.2006078
Abebayehu Dessalegn, M. Balakrishnan, T. Töpfer, L. Podsiadlowski, Tilaye Wube
The genetic diversity of the Ethiopian endemic Ankober Serin Crithagra ankoberensis was studied in two populations at Simien Mountains National Park and Guassa Community Conservation Area using five microsatellite markers. Blood samples were taken from 16 and 14 birds, respectively. Three molecular markers resulted in relatively low, though noticeable differences between the two populations. The analysis also showed the presence of shared alleles, indicating current gene flow between the two populations. Two markers from Simien Mountains National Park and two markers from Guassa Community Conservation Area revealed obvious deviations from the Hardy–Weinberg equilibrium. We interpret these deviations in both populations as limited population size and restricted gene flow. The genetic differentiation between the two populations thus could be explained by their geographical separation (more than 360 km), reinforced by barriers, such as steep mountains, deep valleys and extensive plains (isolation by distance). On the other hand, a stepping-stone mechanism between geographically intermediate populations across small distances might explain the observed gene flow. Further studies are needed to better reconstruct the biogeographic history and conservation needs of the Ankober Serin populations in Ethiopia.
{"title":"Genetic Diversity of the Ankober Serin (Crithagra ankoberensis) at Simien Mountains National Park and Guassa Community Conservation Area, Ethiopia","authors":"Abebayehu Dessalegn, M. Balakrishnan, T. Töpfer, L. Podsiadlowski, Tilaye Wube","doi":"10.1080/15627020.2021.2006078","DOIUrl":"https://doi.org/10.1080/15627020.2021.2006078","url":null,"abstract":"The genetic diversity of the Ethiopian endemic Ankober Serin Crithagra ankoberensis was studied in two populations at Simien Mountains National Park and Guassa Community Conservation Area using five microsatellite markers. Blood samples were taken from 16 and 14 birds, respectively. Three molecular markers resulted in relatively low, though noticeable differences between the two populations. The analysis also showed the presence of shared alleles, indicating current gene flow between the two populations. Two markers from Simien Mountains National Park and two markers from Guassa Community Conservation Area revealed obvious deviations from the Hardy–Weinberg equilibrium. We interpret these deviations in both populations as limited population size and restricted gene flow. The genetic differentiation between the two populations thus could be explained by their geographical separation (more than 360 km), reinforced by barriers, such as steep mountains, deep valleys and extensive plains (isolation by distance). On the other hand, a stepping-stone mechanism between geographically intermediate populations across small distances might explain the observed gene flow. Further studies are needed to better reconstruct the biogeographic history and conservation needs of the Ankober Serin populations in Ethiopia.","PeriodicalId":55548,"journal":{"name":"African Zoology","volume":"56 1","pages":"273 - 278"},"PeriodicalIF":1.1,"publicationDate":"2021-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44449351","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-10-02DOI: 10.1080/15627020.2021.1984988
Mark J Weston, Irfan Nunkoo, C. Reed, C. D. van der Lingen
The South African marine environment is highly diverse, containing >12 000 species of flora and fauna. However, the state of knowledge of marine fish parasites in South African waters is still relatively poor. This study used opportunistic sampling to examine the heads and gills of several commercially valuable marine fish species for ectoparasites with the aim of increasing knowledge of marine parasite biodiversity in South Africa. Samples were collected in 2015 and 2016 from commercial fishing operations, local fishers and research cruises by the Department of Forestry, Fisheries and the Environment and were stored frozen until dissection. The head region, gills and opercula from altogether 621 individual fish from 16 host species were examined. In total, 22 parasite taxa, comprising seven monogeneans and 15 copepods, were recorded, with one new host record and 13 new geographic records catalogued for South Africa. This study increases the knowledge of marine parasite biodiversity in South Africa.
{"title":"Ectoparasites Infecting the Heads and Gills of Commercially Valuable Marine Fishes in South Africa","authors":"Mark J Weston, Irfan Nunkoo, C. Reed, C. D. van der Lingen","doi":"10.1080/15627020.2021.1984988","DOIUrl":"https://doi.org/10.1080/15627020.2021.1984988","url":null,"abstract":"The South African marine environment is highly diverse, containing >12 000 species of flora and fauna. However, the state of knowledge of marine fish parasites in South African waters is still relatively poor. This study used opportunistic sampling to examine the heads and gills of several commercially valuable marine fish species for ectoparasites with the aim of increasing knowledge of marine parasite biodiversity in South Africa. Samples were collected in 2015 and 2016 from commercial fishing operations, local fishers and research cruises by the Department of Forestry, Fisheries and the Environment and were stored frozen until dissection. The head region, gills and opercula from altogether 621 individual fish from 16 host species were examined. In total, 22 parasite taxa, comprising seven monogeneans and 15 copepods, were recorded, with one new host record and 13 new geographic records catalogued for South Africa. This study increases the knowledge of marine parasite biodiversity in South Africa.","PeriodicalId":55548,"journal":{"name":"African Zoology","volume":"56 1","pages":"303 - 311"},"PeriodicalIF":1.1,"publicationDate":"2021-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46205021","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-10-02DOI: 10.1080/15627020.2021.2001370
C. Simon, Agnes WN Muthumbi, C. Kihia, Kyle Smith, R. Cedras, P. Mahatante, V. Wangondu, Robert E. Katikiro
In the Western Indian Ocean (WIO), more than 76 records from peer-reviewed and grey literature identified approximately 60 invertebrate taxa harvested for bait and food. The most diverse phyla were Mollusca, followed by Arthropoda and Annelida, with few records of Porifera, Nemertea and Echinodermata. Importance of each phylum differs according to country, with arthropods (Upogebia africana and Kraussillichirus kraussi), and annelids (Marphysa mossambica) being most important in South Africa and Kenya, respectively. Of the taxa utilised, only 42 are reliably identified to species level, suggesting that the diversity of species utilised in the region is greatly underestimated. Most of the data on biology and exploitation were for species from South Africa. Less data were available from Kenya with minimal to none being available from the remaining WIO countries. This limits the understanding of biology and trends in exploitation of most bait taxa, and consequently information required for developing national and regional management policies. Bait management guidelines are available only for South Africa, but require updating in view of changes in use of bait resources. We recommend the development of coordinated multidisciplinary, multicountry research aimed at increasing data and information to feed into policy development and support national and regional bait resource management.
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