The influence of photoperiod on the reproductive physiology of the greater red musk shrew: Crocidura flavescens
- Hoole, C, McKechnie, Andrew E, Parker, Daniel M, Bennett, Nigel C
- Authors: Hoole, C , McKechnie, Andrew E , Parker, Daniel M , Bennett, Nigel C
- Date: 2016
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/70157 , vital:29626 , https://doi.org/10.1139/cjz-2015-0128
- Description: Photoperiodism involves the use of both absolute measures of day length and the direction in which day length is changing as a cue for regulating seasonal changes in physiology and behaviour so that birth and lactation coincide with optimal resource availability, increasing offspring survival. Induced ovulation and opportunistic breeding is often found in species that are predominantly solitary and territorial. In this study, the photoperiodic reproductive responses of male greater red musk shrews (Crocidura flavescens (I. Geoffroy Saint-Hilaire, 1827)) were investigated in the laboratory. The presence of spermatozoa regardless of the light cycle, suggest that although the shrews are photoresponsive, they may be capable of breeding throughout the year. Significantly greater testicular volume and eminiferous tubule diameter following exposure to a short day-light cycle suggests that these animals may have breeding peaks that correspond to short days. The presence of epidermal spines on the penis indicates that the shrew is likely also an induced ovulator. Flexible breeding patterns combined with induced ovulation affords this solitary species the greatest chance of reproductive success.
- Full Text:
- Date Issued: 2016
- Authors: Hoole, C , McKechnie, Andrew E , Parker, Daniel M , Bennett, Nigel C
- Date: 2016
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/70157 , vital:29626 , https://doi.org/10.1139/cjz-2015-0128
- Description: Photoperiodism involves the use of both absolute measures of day length and the direction in which day length is changing as a cue for regulating seasonal changes in physiology and behaviour so that birth and lactation coincide with optimal resource availability, increasing offspring survival. Induced ovulation and opportunistic breeding is often found in species that are predominantly solitary and territorial. In this study, the photoperiodic reproductive responses of male greater red musk shrews (Crocidura flavescens (I. Geoffroy Saint-Hilaire, 1827)) were investigated in the laboratory. The presence of spermatozoa regardless of the light cycle, suggest that although the shrews are photoresponsive, they may be capable of breeding throughout the year. Significantly greater testicular volume and eminiferous tubule diameter following exposure to a short day-light cycle suggests that these animals may have breeding peaks that correspond to short days. The presence of epidermal spines on the penis indicates that the shrew is likely also an induced ovulator. Flexible breeding patterns combined with induced ovulation affords this solitary species the greatest chance of reproductive success.
- Full Text:
- Date Issued: 2016
Aspects of the biology and life history of largespot pompano, Trachinotus botla, in South Africa
- Parker, Daniel M, Booth, Anthony J
- Authors: Parker, Daniel M , Booth, Anthony J
- Date: 2015
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/123798 , vital:35499 , https://doi.10.1071/MF14029
- Description: Trachinotus botla is an important recreational surf zone-dependent fish species distributed in the Indo-west Pacific from South Africa to Australia. In South Africa it is restricted to the northern KwaZulu-Natal coast. Biological investigations revealed that it is a fast growing species that attains a maximum age of, 7 years. Males and females sexually matured in their third year. It has a protracted summer spawning season with evidence of serial spawning behaviour. T. botla is an opportunistic predator with a generalist diet, with fish feeding on a wide variety of prey items particularly those that are temporally ‘superabundant’. Small fish fed predominantly on copepods and terrestrial insects, whereas larger fish consumed bivalves and crabs. Teleosts, primarily engraulids, were important components to the diet of fish of all sizes. An ontogenetic dietary shift was observed just after sexual maturity (300-mm fork length) that is possibly linked to a change in habitat preference with larger fish foraging on deeper reefs.
- Full Text:
- Date Issued: 2015
- Authors: Parker, Daniel M , Booth, Anthony J
- Date: 2015
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/123798 , vital:35499 , https://doi.10.1071/MF14029
- Description: Trachinotus botla is an important recreational surf zone-dependent fish species distributed in the Indo-west Pacific from South Africa to Australia. In South Africa it is restricted to the northern KwaZulu-Natal coast. Biological investigations revealed that it is a fast growing species that attains a maximum age of, 7 years. Males and females sexually matured in their third year. It has a protracted summer spawning season with evidence of serial spawning behaviour. T. botla is an opportunistic predator with a generalist diet, with fish feeding on a wide variety of prey items particularly those that are temporally ‘superabundant’. Small fish fed predominantly on copepods and terrestrial insects, whereas larger fish consumed bivalves and crabs. Teleosts, primarily engraulids, were important components to the diet of fish of all sizes. An ontogenetic dietary shift was observed just after sexual maturity (300-mm fork length) that is possibly linked to a change in habitat preference with larger fish foraging on deeper reefs.
- Full Text:
- Date Issued: 2015
Brown hyena habitat selection varies among sites in a semi-arid region of southern Africa
- Welch, Rebecca J, Tambling, Craig J, Bissett, Charlene, Gaylard, Angela, Müller, Konrad, Slater, Kerry, Strauss, W Maartin, Parker, Daniel M
- Authors: Welch, Rebecca J , Tambling, Craig J , Bissett, Charlene , Gaylard, Angela , Müller, Konrad , Slater, Kerry , Strauss, W Maartin , Parker, Daniel M
- Date: 2015
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/123277 , vital:35423 , https://doi.10.1093/jmammal/gyv189
- Description: In the last 50 years, the human impact on ecosystems has been greater than during any other time period in human history (Millennium Ecosystem Assessment 2003). Large carnivores face anthropogenic threats worldwide, specifically persecution, habitat degradation, and habitat fragmentation (Everatt et al. 2014; Groom et al. 2014; Ripple et al. 2014; Wolfe et al. 2015). Because large carnivores often occupy high trophic levels, their presence influences species at lower levels through trophic cascades (Ripple et al. 2014). Natural experiments, taking advantage of large carnivore management, have shown that large predators provide fundamental ecosystem and economic services that help maintain healthy and diverse ecosystems (Ripple et al. 2014). Additionally, carnivores play an important role in other ecosystem processes, for example, scavenging carnivores may provide regulatory services, such as waste removal, nutrient cycling, and disease regulation. Such services add stability to ecosystems and ensure energy flow through multiple trophic levels (DeVault et al. 2003; Wilson and Wolkovich 2011).
- Full Text:
- Date Issued: 2015
- Authors: Welch, Rebecca J , Tambling, Craig J , Bissett, Charlene , Gaylard, Angela , Müller, Konrad , Slater, Kerry , Strauss, W Maartin , Parker, Daniel M
- Date: 2015
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/123277 , vital:35423 , https://doi.10.1093/jmammal/gyv189
- Description: In the last 50 years, the human impact on ecosystems has been greater than during any other time period in human history (Millennium Ecosystem Assessment 2003). Large carnivores face anthropogenic threats worldwide, specifically persecution, habitat degradation, and habitat fragmentation (Everatt et al. 2014; Groom et al. 2014; Ripple et al. 2014; Wolfe et al. 2015). Because large carnivores often occupy high trophic levels, their presence influences species at lower levels through trophic cascades (Ripple et al. 2014). Natural experiments, taking advantage of large carnivore management, have shown that large predators provide fundamental ecosystem and economic services that help maintain healthy and diverse ecosystems (Ripple et al. 2014). Additionally, carnivores play an important role in other ecosystem processes, for example, scavenging carnivores may provide regulatory services, such as waste removal, nutrient cycling, and disease regulation. Such services add stability to ecosystems and ensure energy flow through multiple trophic levels (DeVault et al. 2003; Wilson and Wolkovich 2011).
- Full Text:
- Date Issued: 2015
Connectivity through allochthony: Reciprocal links between adjacent aquatic and terrestrial ecosystems in South Africa
- Richoux, Nicole B, Moyo, Sydney, Chari, Lenin D, Bergamino, Leandro, Carassou, Laure, Dalu, Tatenda, Hean, Jeffrey W, Sikutshwa, Likho, Gininda, Simphiwe, Magoro, Mandla L, Perhar, Gurbir, Ni, Felicity, Villet, Martin H, Whitfield, Alan K, Parker, Daniel M, Froneman, P William, Arhonditsis, George, Craig, Adrian J F K
- Authors: Richoux, Nicole B , Moyo, Sydney , Chari, Lenin D , Bergamino, Leandro , Carassou, Laure , Dalu, Tatenda , Hean, Jeffrey W , Sikutshwa, Likho , Gininda, Simphiwe , Magoro, Mandla L , Perhar, Gurbir , Ni, Felicity , Villet, Martin H , Whitfield, Alan K , Parker, Daniel M , Froneman, P William , Arhonditsis, George , Craig, Adrian J F K
- Date: 2015
- Subjects: To be catalogued
- Language: English
- Type: text , report
- Identifier: http://hdl.handle.net/10962/438363 , vital:73454 , ISBN 978-1-4312-0679-7 , https://wrcwebsite.azurewebsites.net/wp-content/uploads/mdocs/2186-1-15.pdf
- Description: An important aspect of the dynamics of nutrients and pollutants in natural systems is captured in the concept of allochthony, founded on the observation that nutrients and energy in a variety of forms are transferred between adjacent habitats, com-munities and ecosystems that are not routinely considered as connected. Different forms of nutrients and energy move across the conceptual boundaries of habitats via organisms’ activities or physical processes such as wind or water currents, and these transfers can represent important food subsidies. Such cross-partition ecolog-ical subsidies can augment the nutritional condition, biomass and biodiversity of communities, particularly where local production (or autochthony) alone may be inadequate to support local food webs. Furthermore, organic subsidies can influ-ence population dynamics, community interactions and ecosystem processes, and can represent dominant flux inputs in ecosystem budgets. Our intention was to ex-plore organic nutrient fluxes in relation to a primarily lotic (i.e. flowing) aquatic sys-tem at the scale of a hydrological catchment.
- Full Text:
- Date Issued: 2015
- Authors: Richoux, Nicole B , Moyo, Sydney , Chari, Lenin D , Bergamino, Leandro , Carassou, Laure , Dalu, Tatenda , Hean, Jeffrey W , Sikutshwa, Likho , Gininda, Simphiwe , Magoro, Mandla L , Perhar, Gurbir , Ni, Felicity , Villet, Martin H , Whitfield, Alan K , Parker, Daniel M , Froneman, P William , Arhonditsis, George , Craig, Adrian J F K
- Date: 2015
- Subjects: To be catalogued
- Language: English
- Type: text , report
- Identifier: http://hdl.handle.net/10962/438363 , vital:73454 , ISBN 978-1-4312-0679-7 , https://wrcwebsite.azurewebsites.net/wp-content/uploads/mdocs/2186-1-15.pdf
- Description: An important aspect of the dynamics of nutrients and pollutants in natural systems is captured in the concept of allochthony, founded on the observation that nutrients and energy in a variety of forms are transferred between adjacent habitats, com-munities and ecosystems that are not routinely considered as connected. Different forms of nutrients and energy move across the conceptual boundaries of habitats via organisms’ activities or physical processes such as wind or water currents, and these transfers can represent important food subsidies. Such cross-partition ecolog-ical subsidies can augment the nutritional condition, biomass and biodiversity of communities, particularly where local production (or autochthony) alone may be inadequate to support local food webs. Furthermore, organic subsidies can influ-ence population dynamics, community interactions and ecosystem processes, and can represent dominant flux inputs in ecosystem budgets. Our intention was to ex-plore organic nutrient fluxes in relation to a primarily lotic (i.e. flowing) aquatic sys-tem at the scale of a hydrological catchment.
- Full Text:
- Date Issued: 2015
Seasonal consumption of browse by the African buffalo (Syncerus caffer) in the Thicket Biome of South Africa
- Watermeyer, Jessica P, Carroll, Sarah L, Parker, Daniel M
- Authors: Watermeyer, Jessica P , Carroll, Sarah L , Parker, Daniel M
- Date: 2015
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/126096 , vital:35849 , https://doi.org/10.1111/aje.12214
- Description: The African buffalo (Syncerus caffer Sparrman) is both morphologically and physiologically adapted for grazing (Prins, 1996). However, buffalo populations of the Eastern Cape, South Africa, are confined to reserves dominated by thicket vegetation where grass is sparse (Landman & Kerley, 2001; Tshabalala, Dube & Lent, 2009). Given that the nutritional value of grass deteriorates more rapidly than browse in nonproductive periods (Shipley, 1993), it has been hypothesized that buffalo increase their intake of browse during the dry season (Tshabalala, Dube & Lent, 2009). However, past studies contradict one another (de Graaf, Schulz & van der Walt, 1973; Landman & Kerley, 2001; Tshabalala, Dube & Lent, 2009). de Graaf, Schulz & van der Walt (1973) analysed the rumen contents of buffalo in the Addo Elephant National Park and suggested that buffalo should be considered browsers because of the high proportion of browse in rumen samples. However, their study was restricted to one site during a drought. Landman & Kerley (2001) later found the opposite (grass comprised ~72% of buffalo dung) and criticized the findings of de Graaf, Schulz amp; van der Walt (1973). However, their study was conducted after a period of exceptionally high rainfall. More recently, Tshabalala, Dube & Lent (2009) recorded significantly more browse in the diet of buffalo during the dry season (33%) than the wet season (28%) at the Great Fish River Nature Reserve. We test the assertion that buffalo increase their intake of browse during dry periods, at another site dominated by thicket. We describe the extent to which grass and browse were consumed by buffalo and whether the proportional occurrence changed monthly.
- Full Text:
- Date Issued: 2015
- Authors: Watermeyer, Jessica P , Carroll, Sarah L , Parker, Daniel M
- Date: 2015
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/126096 , vital:35849 , https://doi.org/10.1111/aje.12214
- Description: The African buffalo (Syncerus caffer Sparrman) is both morphologically and physiologically adapted for grazing (Prins, 1996). However, buffalo populations of the Eastern Cape, South Africa, are confined to reserves dominated by thicket vegetation where grass is sparse (Landman & Kerley, 2001; Tshabalala, Dube & Lent, 2009). Given that the nutritional value of grass deteriorates more rapidly than browse in nonproductive periods (Shipley, 1993), it has been hypothesized that buffalo increase their intake of browse during the dry season (Tshabalala, Dube & Lent, 2009). However, past studies contradict one another (de Graaf, Schulz & van der Walt, 1973; Landman & Kerley, 2001; Tshabalala, Dube & Lent, 2009). de Graaf, Schulz & van der Walt (1973) analysed the rumen contents of buffalo in the Addo Elephant National Park and suggested that buffalo should be considered browsers because of the high proportion of browse in rumen samples. However, their study was restricted to one site during a drought. Landman & Kerley (2001) later found the opposite (grass comprised ~72% of buffalo dung) and criticized the findings of de Graaf, Schulz amp; van der Walt (1973). However, their study was conducted after a period of exceptionally high rainfall. More recently, Tshabalala, Dube & Lent (2009) recorded significantly more browse in the diet of buffalo during the dry season (33%) than the wet season (28%) at the Great Fish River Nature Reserve. We test the assertion that buffalo increase their intake of browse during dry periods, at another site dominated by thicket. We describe the extent to which grass and browse were consumed by buffalo and whether the proportional occurrence changed monthly.
- Full Text:
- Date Issued: 2015
Elephants in Africa: Big, grey biodiversity thieves?
- Kuiper, Timothy R, Parker, Daniel M
- Authors: Kuiper, Timothy R , Parker, Daniel M
- Date: 2014
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/124385 , vital:35601 , https://doi.org/10.2989/16085914.2011.589120
- Description: The conservation of biological diversity is one of the greatest challenges facing humanity today.1,2 Addressing this challenge must inevitably involve the maintenance of the composition, structure and functioning of multi-species ecosystems.2-4 While preventing the loss of particular species is an obvious strategy, a second goal might be to manage for local species diversity and the heterogeneity of habitats.5 A further objective may be the restoration of damaged ecosystems.6 Large herbivore assemblages form an important component of many diverse ecosystems and are of distinct ecological, and hence conservation, value.7-9 On the other hand, herbivores managed at unnaturally high densities may drive detrimental changes in the structural heterogeneity of habitats.10-12 Thus, decision-makers are faced with the challenge of balancing the needs of populations of large herbivores with the preservation of vegetation and ecosystem diversity.9 In light of these considerations, conclusions as to whether large herbivores are ‘good’ or ‘bad’ for biological diversity are both contentious and elusive. Nonetheless, we seek to explore this question with particular reference to African savannah elephants (Loxodonta africana). We discuss whether or not the elephant should be considered a biodiversity thief – a species that upsets the natural diversity of life in the habitat in which it lives.
- Full Text:
- Date Issued: 2014
- Authors: Kuiper, Timothy R , Parker, Daniel M
- Date: 2014
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/124385 , vital:35601 , https://doi.org/10.2989/16085914.2011.589120
- Description: The conservation of biological diversity is one of the greatest challenges facing humanity today.1,2 Addressing this challenge must inevitably involve the maintenance of the composition, structure and functioning of multi-species ecosystems.2-4 While preventing the loss of particular species is an obvious strategy, a second goal might be to manage for local species diversity and the heterogeneity of habitats.5 A further objective may be the restoration of damaged ecosystems.6 Large herbivore assemblages form an important component of many diverse ecosystems and are of distinct ecological, and hence conservation, value.7-9 On the other hand, herbivores managed at unnaturally high densities may drive detrimental changes in the structural heterogeneity of habitats.10-12 Thus, decision-makers are faced with the challenge of balancing the needs of populations of large herbivores with the preservation of vegetation and ecosystem diversity.9 In light of these considerations, conclusions as to whether large herbivores are ‘good’ or ‘bad’ for biological diversity are both contentious and elusive. Nonetheless, we seek to explore this question with particular reference to African savannah elephants (Loxodonta africana). We discuss whether or not the elephant should be considered a biodiversity thief – a species that upsets the natural diversity of life in the habitat in which it lives.
- Full Text:
- Date Issued: 2014
Elephants in Africa: Big, grey biodiversity thieves?
- Kuiper, Timothy R, Parker, Daniel M
- Authors: Kuiper, Timothy R , Parker, Daniel M
- Date: 2014
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/69886 , vital:29591 , http://dx.doi.org/10.1590/ sajs.2014/a0058
- Description: The conservation of biological diversity is one of the greatest challenges facing humanity today.1,2 Addressing this challenge must inevitably involve the maintenance of the composition, structure and functioning of multi-species ecosystems.2-4 While preventing the loss of particular species is an obvious strategy, a second goal might be to manage for local species diversity and the heterogeneity of habitats.5 A further objective may be the restoration of damaged ecosystems.6 Large herbivore assemblages form an important component of many diverse ecosystems and are of distinct ecological, and hence conservation, value.7-9 On the other hand, herbivores managed at unnaturally high densities may drive detrimental changes in the structural heterogeneity of habitats.10-12 Thus, decision-makers are faced with the challenge of balancing the needs of populations of large herbivores with the preservation of vegetation and ecosystem diversity.9 In light of these considerations, conclusions as to whether large herbivores are 'good' or 'bad' for biological diversity are both contentious and elusive. Nonetheless, we seek to explore this question with particular reference to African savannah elephants (Loxodonta africana). We discuss whether or not the elephant should be considered a biodiversity thief - a species that upsets the natural diversity of life in the habitat in which it lives. The African elephant has been driven to local extinction over much of its former range, with hunting for meat and ivory and the conversion of elephant habitat to agriculture constituting the major drivers.5 Given the historical decline in elephant numbers, the conservation of this species appears to be a sensible objective.9,13 However, the protection afforded to elephants in confined (usually fenced) reserves across Africa has distinct implications for the management of local species diversity and the heterogeneity of habitats.14,15 Elephants have been shown to have clear impacts on the structure of vegetation, particularly in woodland habitats12,16,17, and these changes may have knock-on effects for sympatric species10,18,19. The effects of elephants on biological diversity in protected areas are of particular concern in light of how expansion in human populations, and the land-use change that follows, places increasing pressure on reserves to preserve biological diversity.9,10. Change within ecosystems is natural and inevitable and large herbivores have been living in an ever-changing environment for millions of years.20 Changes brought on by elephants, therefore, should not automatically be categorised as undesirable, and short-term changes may be part of an overarching trend of long-term stability.8,21 Furthermore, current elephant impacts can only be adequately assessed in the light of historical (on the scale of centuries) benchmarks, for which accurate information is notoriously scant.10,21 The current impacts of elephant populations on vegetation dynamics in some regions may in fact represent a shift towards a more natural historical state.8,21 Finally, much of the detrimental impacts of elephants on habitat structure and diversity, particularly at smaller scales, has resulted from human interventions (such as the erection of fences and the establishment of artificial water points) that have unnaturally confined elephants to localised areas, disrupted seasonal movements and disturbed the natural dynamics of population processes.5,13,22.
- Full Text:
- Date Issued: 2014
- Authors: Kuiper, Timothy R , Parker, Daniel M
- Date: 2014
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/69886 , vital:29591 , http://dx.doi.org/10.1590/ sajs.2014/a0058
- Description: The conservation of biological diversity is one of the greatest challenges facing humanity today.1,2 Addressing this challenge must inevitably involve the maintenance of the composition, structure and functioning of multi-species ecosystems.2-4 While preventing the loss of particular species is an obvious strategy, a second goal might be to manage for local species diversity and the heterogeneity of habitats.5 A further objective may be the restoration of damaged ecosystems.6 Large herbivore assemblages form an important component of many diverse ecosystems and are of distinct ecological, and hence conservation, value.7-9 On the other hand, herbivores managed at unnaturally high densities may drive detrimental changes in the structural heterogeneity of habitats.10-12 Thus, decision-makers are faced with the challenge of balancing the needs of populations of large herbivores with the preservation of vegetation and ecosystem diversity.9 In light of these considerations, conclusions as to whether large herbivores are 'good' or 'bad' for biological diversity are both contentious and elusive. Nonetheless, we seek to explore this question with particular reference to African savannah elephants (Loxodonta africana). We discuss whether or not the elephant should be considered a biodiversity thief - a species that upsets the natural diversity of life in the habitat in which it lives. The African elephant has been driven to local extinction over much of its former range, with hunting for meat and ivory and the conversion of elephant habitat to agriculture constituting the major drivers.5 Given the historical decline in elephant numbers, the conservation of this species appears to be a sensible objective.9,13 However, the protection afforded to elephants in confined (usually fenced) reserves across Africa has distinct implications for the management of local species diversity and the heterogeneity of habitats.14,15 Elephants have been shown to have clear impacts on the structure of vegetation, particularly in woodland habitats12,16,17, and these changes may have knock-on effects for sympatric species10,18,19. The effects of elephants on biological diversity in protected areas are of particular concern in light of how expansion in human populations, and the land-use change that follows, places increasing pressure on reserves to preserve biological diversity.9,10. Change within ecosystems is natural and inevitable and large herbivores have been living in an ever-changing environment for millions of years.20 Changes brought on by elephants, therefore, should not automatically be categorised as undesirable, and short-term changes may be part of an overarching trend of long-term stability.8,21 Furthermore, current elephant impacts can only be adequately assessed in the light of historical (on the scale of centuries) benchmarks, for which accurate information is notoriously scant.10,21 The current impacts of elephant populations on vegetation dynamics in some regions may in fact represent a shift towards a more natural historical state.8,21 Finally, much of the detrimental impacts of elephants on habitat structure and diversity, particularly at smaller scales, has resulted from human interventions (such as the erection of fences and the establishment of artificial water points) that have unnaturally confined elephants to localised areas, disrupted seasonal movements and disturbed the natural dynamics of population processes.5,13,22.
- Full Text:
- Date Issued: 2014
New possibilities for research on reef fish across the continental shelf of South Africa
- Bernard, Anthony T F, Götz, Albrecht, Parker, Daniel M, Heyns, Elodie R, Halse, Sarah J, Riddin, N A, Smith, M K S, Paterson, Angus W, Winker, A Henning, Fullwood, L, Langlois, T J, Harvey, E S
- Authors: Bernard, Anthony T F , Götz, Albrecht , Parker, Daniel M , Heyns, Elodie R , Halse, Sarah J , Riddin, N A , Smith, M K S , Paterson, Angus W , Winker, A Henning , Fullwood, L , Langlois, T J , Harvey, E S
- Date: 2014
- Language: English
- Type: Article
- Identifier: vital:6971 , http://hdl.handle.net/10962/d1014566
- Description: [From introduction] Subtidal research presents numerous challenges that restrict the ability to answer fundamental ecological questions related to reef systems. These challenges are closely associated with traditional monitoring methods and include depth restrictions (e.g. safe diving depths for underwater visual census), habitat destruction (e.g. trawling), mortality of target species (e.g. controlled angling and fish traps), and high operating costs (e.g. remotely operated vehicles and large research vessels. Whereas many of these challenges do not apply or are avoidable in the shallow subtidal environment, the difficulties grow as one attempts to sample deeper benthic habitats. This situation has resulted in a paucity of knowledge on the structure and ecology of deep water reef habitats around the coast of South Africa and in most marine areas around the world. Furthermore, the inability to effectively survey deep water benthic environments has limited the capacity of researchers to investigate connectivity between shallow and deep water habitats in a standardised and comparable fashion.
- Full Text:
- Date Issued: 2014
- Authors: Bernard, Anthony T F , Götz, Albrecht , Parker, Daniel M , Heyns, Elodie R , Halse, Sarah J , Riddin, N A , Smith, M K S , Paterson, Angus W , Winker, A Henning , Fullwood, L , Langlois, T J , Harvey, E S
- Date: 2014
- Language: English
- Type: Article
- Identifier: vital:6971 , http://hdl.handle.net/10962/d1014566
- Description: [From introduction] Subtidal research presents numerous challenges that restrict the ability to answer fundamental ecological questions related to reef systems. These challenges are closely associated with traditional monitoring methods and include depth restrictions (e.g. safe diving depths for underwater visual census), habitat destruction (e.g. trawling), mortality of target species (e.g. controlled angling and fish traps), and high operating costs (e.g. remotely operated vehicles and large research vessels. Whereas many of these challenges do not apply or are avoidable in the shallow subtidal environment, the difficulties grow as one attempts to sample deeper benthic habitats. This situation has resulted in a paucity of knowledge on the structure and ecology of deep water reef habitats around the coast of South Africa and in most marine areas around the world. Furthermore, the inability to effectively survey deep water benthic environments has limited the capacity of researchers to investigate connectivity between shallow and deep water habitats in a standardised and comparable fashion.
- Full Text:
- Date Issued: 2014
Rules of attraction: the role of bait in small mammal sampling at high altitude in South Africa
- Kok, Armand D, Parker, Daniel M, Barker, Nigel P
- Authors: Kok, Armand D , Parker, Daniel M , Barker, Nigel P
- Date: 2013
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/443936 , vital:74173 , https://doi.org/10.1080/15627020.2013.11407571
- Description: Baits or lures are commonly used for surveying small mammal communities, not only because they attract large numbers of these animals, but also because they provide sustenance for trapped individuals. In this study we used Sherman live traps with five bait treatments to sample small mammal populations at three high-altitude sites (>1700 m) in the Sneeuberg Mountain Complex of the Eastern Cape Province, South Africa.We investigated the influence of bait treatment on three parameters commonly recorded in small mammal surveys. In addition, we investigated how different bait treatments vary in measuring species richness using the Chao 2 species richness estimator together with rarefaction curves. Overall, 12 small mammal species were sampled. A combination of birdseed and banana captured the highest number of species (11) but the most successful bait overall was peanut butter and oats (greatest number of captures, recaptures, number of individuals and highest Shannon diversity). The Chao 2 richness estimator indicated that four of the five bait treatments reached their sampling capacity. Rarefaction curves indicated that all bait treatments are similar with regard to species accumulation. This could possibly be explained by odours left behind in traps as even un-baited traps (i.e. controls) captured seven different small mammal species. We conclude that the most suitable bait for surveying small mammals at high altitude in South Africa is peanut butter and oats. However, using peanut butter and oats in combination with other bait treatments will improve estimates of diversity when surveying small mammal communities.
- Full Text:
- Date Issued: 2013
- Authors: Kok, Armand D , Parker, Daniel M , Barker, Nigel P
- Date: 2013
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/443936 , vital:74173 , https://doi.org/10.1080/15627020.2013.11407571
- Description: Baits or lures are commonly used for surveying small mammal communities, not only because they attract large numbers of these animals, but also because they provide sustenance for trapped individuals. In this study we used Sherman live traps with five bait treatments to sample small mammal populations at three high-altitude sites (>1700 m) in the Sneeuberg Mountain Complex of the Eastern Cape Province, South Africa.We investigated the influence of bait treatment on three parameters commonly recorded in small mammal surveys. In addition, we investigated how different bait treatments vary in measuring species richness using the Chao 2 species richness estimator together with rarefaction curves. Overall, 12 small mammal species were sampled. A combination of birdseed and banana captured the highest number of species (11) but the most successful bait overall was peanut butter and oats (greatest number of captures, recaptures, number of individuals and highest Shannon diversity). The Chao 2 richness estimator indicated that four of the five bait treatments reached their sampling capacity. Rarefaction curves indicated that all bait treatments are similar with regard to species accumulation. This could possibly be explained by odours left behind in traps as even un-baited traps (i.e. controls) captured seven different small mammal species. We conclude that the most suitable bait for surveying small mammals at high altitude in South Africa is peanut butter and oats. However, using peanut butter and oats in combination with other bait treatments will improve estimates of diversity when surveying small mammal communities.
- Full Text:
- Date Issued: 2013
Aardvark burrows: a potential resource for animals in arid and semi-arid environments
- Whittington-Jones, Gareth M, Bernard, Ric T F, Parker, Daniel M
- Authors: Whittington-Jones, Gareth M , Bernard, Ric T F , Parker, Daniel M
- Date: 2011
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/443852 , vital:74166 , https://doi.org/10.1080/15627020.2011.11407509
- Description: Arid and semi-arid environments are characterized by extreme fluctuations in temperature and low rainfall, which present significant challenges to the animals inhabiting these areas. However, the presence of burrows may allow animals to avoid climatic extremes and predators and may act as valuable foraging sites. We assessed the microhabitat conditions (maximum and minimum temperature, relative humidity and seed abundance) of aardvark (Orycteropus afer) burrows in relation to paired non-burrow areas at three sites in South Africa. We also describe the extent to which they are used as resources by other vertebrates. Maximum temperatures were significantly lower and minimum temperatures and relative humidity values were significantly higher inside the burrows than outside. The concentration of seeds inside the burrows and at the paired non-burrow sites was similar. Twenty-seven vertebrate species (21 mammals, two birds, three reptiles and one amphibian) were recorded making use of the burrows and it is likely that these species accrue benefits (e.g. a buffered microclimate) from burrow use. However, our sampling was biased towards mammals and nocturnal species. Consequently, we recommend further work to establish the overall reliance of vertebrate taxa on aardvark burrows in arid and semi-arid environments.
- Full Text:
- Date Issued: 2011
- Authors: Whittington-Jones, Gareth M , Bernard, Ric T F , Parker, Daniel M
- Date: 2011
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/443852 , vital:74166 , https://doi.org/10.1080/15627020.2011.11407509
- Description: Arid and semi-arid environments are characterized by extreme fluctuations in temperature and low rainfall, which present significant challenges to the animals inhabiting these areas. However, the presence of burrows may allow animals to avoid climatic extremes and predators and may act as valuable foraging sites. We assessed the microhabitat conditions (maximum and minimum temperature, relative humidity and seed abundance) of aardvark (Orycteropus afer) burrows in relation to paired non-burrow areas at three sites in South Africa. We also describe the extent to which they are used as resources by other vertebrates. Maximum temperatures were significantly lower and minimum temperatures and relative humidity values were significantly higher inside the burrows than outside. The concentration of seeds inside the burrows and at the paired non-burrow sites was similar. Twenty-seven vertebrate species (21 mammals, two birds, three reptiles and one amphibian) were recorded making use of the burrows and it is likely that these species accrue benefits (e.g. a buffered microclimate) from burrow use. However, our sampling was biased towards mammals and nocturnal species. Consequently, we recommend further work to establish the overall reliance of vertebrate taxa on aardvark burrows in arid and semi-arid environments.
- Full Text:
- Date Issued: 2011
Bushclumps as refugia for small mammals in two Eastern Cape conservation areas
- Whittington-Jones, Gareth M, Bernard, Ric T F, Parker, Daniel M
- Authors: Whittington-Jones, Gareth M , Bernard, Ric T F , Parker, Daniel M
- Date: 2008
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/446975 , vital:74574 , https://hdl.handle.net/10520/EJC18077
- Description: Bushclumps are scattered islands of thicket-like vegetation within a matrix of more open vegetation. We investigated the role of bushclumps as refugia for small mammals, and examined the effect of a limited number of abiotic and biotic factors on their richness, diversity and abundance. Small mammals were surveyed using Sherman small mammal traps at two sites in the Eastern Cape Province, South Africa (Mountain Zebra National Park and Kwandwe Private Game Reserve). Soil hardness and seed abundance, inside and outside bushclumps, were determined. Trap success was significantly higher inside bushclumps than in areas outside, and species diversity and the abundance of small mammals were greater within bushclumps compared to outside. Bushclumps also had significantly softer soil and a higher concentration of seeds. We conclude that bushclumps provide a concentrated source of food and protection from predators for small mammals, and are thus used significantly more than adjacent open areas. The conservation of bushclumps is therefore important for the overall maintenance of ecosystem functioning.
- Full Text:
- Date Issued: 2008
- Authors: Whittington-Jones, Gareth M , Bernard, Ric T F , Parker, Daniel M
- Date: 2008
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/446975 , vital:74574 , https://hdl.handle.net/10520/EJC18077
- Description: Bushclumps are scattered islands of thicket-like vegetation within a matrix of more open vegetation. We investigated the role of bushclumps as refugia for small mammals, and examined the effect of a limited number of abiotic and biotic factors on their richness, diversity and abundance. Small mammals were surveyed using Sherman small mammal traps at two sites in the Eastern Cape Province, South Africa (Mountain Zebra National Park and Kwandwe Private Game Reserve). Soil hardness and seed abundance, inside and outside bushclumps, were determined. Trap success was significantly higher inside bushclumps than in areas outside, and species diversity and the abundance of small mammals were greater within bushclumps compared to outside. Bushclumps also had significantly softer soil and a higher concentration of seeds. We conclude that bushclumps provide a concentrated source of food and protection from predators for small mammals, and are thus used significantly more than adjacent open areas. The conservation of bushclumps is therefore important for the overall maintenance of ecosystem functioning.
- Full Text:
- Date Issued: 2008
Lessons from aloes in the Thicket Biome: reconstructing past elephant browsing to understand the present
- Parker, Daniel M, Bernard, Ric T F
- Authors: Parker, Daniel M , Bernard, Ric T F
- Date: 2008
- Language: English
- Type: Article
- Identifier: vital:6894 , http://hdl.handle.net/10962/d1011654
- Description: It is very difficult to quantify elephant-induced change to vegetation in the absence of adequate historical benchmarks. In this commentary, we explore the historical distribution of aloes in the Thicket Biome of South Africa. We contend that the large stands of aesthetically pleasing aloes in the Thicket Biome can be likened to the even-aged stands of tall trees in the riparian forests of Botswana, both being artefacts of the loss of large herbivores through disease and hunting in the past. Elephant browsing on aloes may therefore be the first step in the vegetation reverting to a situation similar to the one prior to excessive hunting in the region.
- Full Text:
- Date Issued: 2008
- Authors: Parker, Daniel M , Bernard, Ric T F
- Date: 2008
- Language: English
- Type: Article
- Identifier: vital:6894 , http://hdl.handle.net/10962/d1011654
- Description: It is very difficult to quantify elephant-induced change to vegetation in the absence of adequate historical benchmarks. In this commentary, we explore the historical distribution of aloes in the Thicket Biome of South Africa. We contend that the large stands of aesthetically pleasing aloes in the Thicket Biome can be likened to the even-aged stands of tall trees in the riparian forests of Botswana, both being artefacts of the loss of large herbivores through disease and hunting in the past. Elephant browsing on aloes may therefore be the first step in the vegetation reverting to a situation similar to the one prior to excessive hunting in the region.
- Full Text:
- Date Issued: 2008
The use of archaeological and ethnographical information to supplement the historical record of the distribution of large mammalian herbivores in South Africa
- Bernard, Ric T F, Parker, Daniel M
- Authors: Bernard, Ric T F , Parker, Daniel M
- Date: 2006
- Language: English
- Type: Article
- Identifier: vital:6914 , http://hdl.handle.net/10962/d1011877
- Description: Introduction: The introduction of animal taxa to areas where they do not naturally occur has the potential to damage severely the native fauna and flora. Introductions, both accidental and intentional, to Australia, New Zealand, Marion Island and other oceanic islands provide spectacular examples of this.1,2 Non-native mammalian herbivores often become invasive in the absence of their natural predators2 and their impact on vegetation, which may include alterations to plant species composition, structure and diversity, is exaggerated, especially if the vegetation has evolved in the absence of similar herbivores.3,4 This influence is not limited to the direct consequence for the vegetation and there may be a cascade effect on ecosystem functioning through, for example, a decline in the amount of available forage for indigenous herbivores,3 a reduction in the breeding efficiency of birds that rely on the vegetation,5,6 and a negative effect on carbon storage by transforming stands of dense vegetative cover to open savannah like systems.7 Nor are these outcomes restricted to non-native herbivores; the re-introduction of a species, such as the elephant (Loxodonta africana), to areas from which it has been absent for many years may have similar consequences.8–11 Additional problems associated with the uncontrolled movement of large mammals include the transmission of disease, such as brucellosis in the United States,3 and a threat to the genetic integrity of a species through hybridization.12 It is thus clear that deliberate introductions of herbivores to areas where they do not naturally occur may not be sound conservation practice.
- Full Text:
- Date Issued: 2006
- Authors: Bernard, Ric T F , Parker, Daniel M
- Date: 2006
- Language: English
- Type: Article
- Identifier: vital:6914 , http://hdl.handle.net/10962/d1011877
- Description: Introduction: The introduction of animal taxa to areas where they do not naturally occur has the potential to damage severely the native fauna and flora. Introductions, both accidental and intentional, to Australia, New Zealand, Marion Island and other oceanic islands provide spectacular examples of this.1,2 Non-native mammalian herbivores often become invasive in the absence of their natural predators2 and their impact on vegetation, which may include alterations to plant species composition, structure and diversity, is exaggerated, especially if the vegetation has evolved in the absence of similar herbivores.3,4 This influence is not limited to the direct consequence for the vegetation and there may be a cascade effect on ecosystem functioning through, for example, a decline in the amount of available forage for indigenous herbivores,3 a reduction in the breeding efficiency of birds that rely on the vegetation,5,6 and a negative effect on carbon storage by transforming stands of dense vegetative cover to open savannah like systems.7 Nor are these outcomes restricted to non-native herbivores; the re-introduction of a species, such as the elephant (Loxodonta africana), to areas from which it has been absent for many years may have similar consequences.8–11 Additional problems associated with the uncontrolled movement of large mammals include the transmission of disease, such as brucellosis in the United States,3 and a threat to the genetic integrity of a species through hybridization.12 It is thus clear that deliberate introductions of herbivores to areas where they do not naturally occur may not be sound conservation practice.
- Full Text:
- Date Issued: 2006
A re-assessment of the avifauna of the Mountain Zebra National Park
- Craig, Adrian J F K, Hulley, Patrick E, Parker, Daniel M
- Authors: Craig, Adrian J F K , Hulley, Patrick E , Parker, Daniel M
- Date: 2005
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/465267 , vital:76588 , 10.4102/koedoe.v63i1.1683
- Description: Based on all published records, together with the original data for the southern African bird atlas, the current Birds in Reserves Project and our records on field trips, 257 bird species have been reliably recorded from MZNP. We have assessed the current status of all species, in relation to the recent expansion of the park and other changes which may be a consequence of management practices. No birds of national conservation concern are breeding residents in the park, and some species are periodic or irregular visitors. Nevertheless, the park is important for the conservation of representatives of the Karoo avifauna, and the diversity of birdlife present should be highlighted to attract visitors with a special interest in birding.
- Full Text:
- Date Issued: 2005
- Authors: Craig, Adrian J F K , Hulley, Patrick E , Parker, Daniel M
- Date: 2005
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/465267 , vital:76588 , 10.4102/koedoe.v63i1.1683
- Description: Based on all published records, together with the original data for the southern African bird atlas, the current Birds in Reserves Project and our records on field trips, 257 bird species have been reliably recorded from MZNP. We have assessed the current status of all species, in relation to the recent expansion of the park and other changes which may be a consequence of management practices. No birds of national conservation concern are breeding residents in the park, and some species are periodic or irregular visitors. Nevertheless, the park is important for the conservation of representatives of the Karoo avifauna, and the diversity of birdlife present should be highlighted to attract visitors with a special interest in birding.
- Full Text:
- Date Issued: 2005
The diet and ecological role of giraffe (Giraffa camelopardalis) introduced to the Eastern Cape, South Africa
- Parker, Daniel M, Bernard, Ric T F
- Authors: Parker, Daniel M , Bernard, Ric T F
- Date: 2005
- Subjects: Giraffe Giraffa camelopardalis Herbivore
- Language: English
- Type: Article
- Identifier: vital:6942 , http://hdl.handle.net/10962/d1011967
- Description: With an increase in the popularity of wildlife ranching in southern Africa has come the introduction of non-native (extralimital) mammalian herbivores. Financial gain has arguably been at the forefront of these introductions, with little or no assessment of the ecological consequences. The diet of three populations of introduced giraffe Giraffa camelopardalis was assessed by direct observation in the Eastern Cape Province, South Africa between January 2002 and October 2003, as the first step towards understanding the ecological role played by giraffe in the region. Similar to the diet of giraffe within their native range, a deciduous species from the genus Acacia (Acacia karroo) was the most important species in the diet. Giraffe in the Eastern Cape Province, however, consumed more evergreen species than those within their native range. The relative lack of deciduous species in the Eastern Cape Province provides a probable explanation for such a result. Seasonal variation in the consumption of the most important species in the diet was evident with members of the genus Rhus being more important in the winter months. This was attributed to the deciduous nature of A. karroo. The potential for giraffe to have a detrimental effect on the indigenous vegetation is discussed. We conclude that the study provides a much-needed list of plant species threatened by giraffe browsing in a region where the vegetation is thought to have evolved in the absence of such a browser.
- Full Text:
- Date Issued: 2005
- Authors: Parker, Daniel M , Bernard, Ric T F
- Date: 2005
- Subjects: Giraffe Giraffa camelopardalis Herbivore
- Language: English
- Type: Article
- Identifier: vital:6942 , http://hdl.handle.net/10962/d1011967
- Description: With an increase in the popularity of wildlife ranching in southern Africa has come the introduction of non-native (extralimital) mammalian herbivores. Financial gain has arguably been at the forefront of these introductions, with little or no assessment of the ecological consequences. The diet of three populations of introduced giraffe Giraffa camelopardalis was assessed by direct observation in the Eastern Cape Province, South Africa between January 2002 and October 2003, as the first step towards understanding the ecological role played by giraffe in the region. Similar to the diet of giraffe within their native range, a deciduous species from the genus Acacia (Acacia karroo) was the most important species in the diet. Giraffe in the Eastern Cape Province, however, consumed more evergreen species than those within their native range. The relative lack of deciduous species in the Eastern Cape Province provides a probable explanation for such a result. Seasonal variation in the consumption of the most important species in the diet was evident with members of the genus Rhus being more important in the winter months. This was attributed to the deciduous nature of A. karroo. The potential for giraffe to have a detrimental effect on the indigenous vegetation is discussed. We conclude that the study provides a much-needed list of plant species threatened by giraffe browsing in a region where the vegetation is thought to have evolved in the absence of such a browser.
- Full Text:
- Date Issued: 2005
The diet of Cape clawless otters at two sites along the Bloukrans River, Eastern Cape Province, South Africa
- Parker, Daniel M, Burchell, R K, Bernard, Ric T F
- Authors: Parker, Daniel M , Burchell, R K , Bernard, Ric T F
- Date: 2005
- Language: English
- Type: Article
- Identifier: vital:6959 , http://hdl.handle.net/10962/d1012004
- Description: The diet of Cape clawless otters was assessed at two sites along the Bloukrans River using faecal analysis. Spraints (n = 78) were collected during 2000 and 2001 and analysed using the relative frequency of occurrence and the reconstituted wet weight methods. Both methods found crab (Potamonautes perlatus) to be the most important component (>50%) of the diet. Frog, Xenopus and Rana spp., (11–42%) was the second most important component while fish (Micropteris salmoides) was relatively unimportant (<14%). Although the diet of Cape clawless otters in the Eastern Cape Province was similar to that reported elsewhere, the fact that they were preying on an alien invasive fish and not the indigenous endemic Sandelia bainsii is significant. The validity of faecal analysis methods is also discussed.
- Full Text:
- Date Issued: 2005
- Authors: Parker, Daniel M , Burchell, R K , Bernard, Ric T F
- Date: 2005
- Language: English
- Type: Article
- Identifier: vital:6959 , http://hdl.handle.net/10962/d1012004
- Description: The diet of Cape clawless otters was assessed at two sites along the Bloukrans River using faecal analysis. Spraints (n = 78) were collected during 2000 and 2001 and analysed using the relative frequency of occurrence and the reconstituted wet weight methods. Both methods found crab (Potamonautes perlatus) to be the most important component (>50%) of the diet. Frog, Xenopus and Rana spp., (11–42%) was the second most important component while fish (Micropteris salmoides) was relatively unimportant (<14%). Although the diet of Cape clawless otters in the Eastern Cape Province was similar to that reported elsewhere, the fact that they were preying on an alien invasive fish and not the indigenous endemic Sandelia bainsii is significant. The validity of faecal analysis methods is also discussed.
- Full Text:
- Date Issued: 2005
The diet of a small group of extralimital giraffe
- Parker, Daniel M, Bernard, Ric T F, Colvin, S A
- Authors: Parker, Daniel M , Bernard, Ric T F , Colvin, S A
- Date: 2003
- Language: English
- Type: Article
- Identifier: vital:6950 , http://hdl.handle.net/10962/d1011980
- Description: Giraffe are extralimital in the Eastern Cape Province, South Africa where recent local introductions have persisted despite limited research into their impact on the indigenous flora. The diet of 15 giraffe at the Shamwari Game Reserve was recorded by direct observation during summer (March/April) and winter (July/August) 2001, quantifying diet by frequency of occurrence (individual records scored and expressed as a percentage of the total). Preference indices were also calculated. Habitat use was measured by the number of hours giraffe fed in different habitats. The diet comprised of 14 plant species, the most important species being Rhus longispina (47.9%), Acacia karroo (25.7%) and Euclea undulata (17.6%). Importance of R. longispina, A. karroo and Tarchonanthus camphoratus fluctuated seasonally. Rhus longispina was more important in winter with a corresponding decrease in feeding on A. karroo. Tarchonanthus camphoratus was only consumed during summer. Acacia karroo thickets (previously disturbed areas) were utilized most (summer 12 h; winter 9 h), with alternative habitats utilized more often in winter than in summer. We suggest that the seasonal fluctuation in the importance of R. longispina & A. karroo reflects the deciduous nature of A. karroo.
- Full Text:
- Date Issued: 2003
- Authors: Parker, Daniel M , Bernard, Ric T F , Colvin, S A
- Date: 2003
- Language: English
- Type: Article
- Identifier: vital:6950 , http://hdl.handle.net/10962/d1011980
- Description: Giraffe are extralimital in the Eastern Cape Province, South Africa where recent local introductions have persisted despite limited research into their impact on the indigenous flora. The diet of 15 giraffe at the Shamwari Game Reserve was recorded by direct observation during summer (March/April) and winter (July/August) 2001, quantifying diet by frequency of occurrence (individual records scored and expressed as a percentage of the total). Preference indices were also calculated. Habitat use was measured by the number of hours giraffe fed in different habitats. The diet comprised of 14 plant species, the most important species being Rhus longispina (47.9%), Acacia karroo (25.7%) and Euclea undulata (17.6%). Importance of R. longispina, A. karroo and Tarchonanthus camphoratus fluctuated seasonally. Rhus longispina was more important in winter with a corresponding decrease in feeding on A. karroo. Tarchonanthus camphoratus was only consumed during summer. Acacia karroo thickets (previously disturbed areas) were utilized most (summer 12 h; winter 9 h), with alternative habitats utilized more often in winter than in summer. We suggest that the seasonal fluctuation in the importance of R. longispina & A. karroo reflects the deciduous nature of A. karroo.
- Full Text:
- Date Issued: 2003