Counting waterbirds on holiday: a snapshot for one Eastern Cape estuary
- Mullins, R Lorraine G, Craig, Adrian J F K
- Authors: Mullins, R Lorraine G , Craig, Adrian J F K
- Date: 2020
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/449375 , vital:74815 , https://doi.org/10.2989/00306525.2020.1783383
- Description: Over a ten-year period, each December the same observer counted waterbirds on the same stretch of the Kariega River in the Eastern Cape, South Africa. The site surveyed is dominated by waders, with variable numbers of other feeding guilds. Piscivorous birds in particular are poorly represented. Differences in the numbers of birds and species recorded, both within a single month and between years, are only partly explicable by environmental conditions on this permanently open estuary. From our comparison with nearby sites, we conclude local movements between rivers and pans in the region must occur regularly over short time intervals.
- Full Text:
- Authors: Mullins, R Lorraine G , Craig, Adrian J F K
- Date: 2020
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/449375 , vital:74815 , https://doi.org/10.2989/00306525.2020.1783383
- Description: Over a ten-year period, each December the same observer counted waterbirds on the same stretch of the Kariega River in the Eastern Cape, South Africa. The site surveyed is dominated by waders, with variable numbers of other feeding guilds. Piscivorous birds in particular are poorly represented. Differences in the numbers of birds and species recorded, both within a single month and between years, are only partly explicable by environmental conditions on this permanently open estuary. From our comparison with nearby sites, we conclude local movements between rivers and pans in the region must occur regularly over short time intervals.
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Montane forest birds in winter: do they regularly move to lower altitudes? Observations from the Eastern Cape, South Africa
- Craig, Adrian J F K, Hulley, Patrick E
- Authors: Craig, Adrian J F K , Hulley, Patrick E
- Date: 2019
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/449433 , vital:74821 , https://doi.org/10.2989/00306525.2019.1568316
- Description: Seasonal altitudinal migration to lower altitudes including the coast has been ascribed to a number of forest birds, of which 14 species occur at Fort Fordyce Reserve in the Eastern Cape, South Africa. Based on our observations and ringing at this site (2007–2017), as well as concurrent data from the South African Bird Atlas Project (SABAP2), we suggest that in this region only three species, the African Dusky Flycatcher Muscicapa adusta, White-starred Robin Pogonocichla stellata and Barratt's Warbler Bradypterus barratti, are regular altitudinal migrants. For two other species, the Grey Cuckooshrike Coracina caesia and Yellow-throated Woodland Warbler Phylloscopus ruficapilla, local movements apparently occur, but these may take place within the coastal zone rather than between the coast and inland forests.
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- Authors: Craig, Adrian J F K , Hulley, Patrick E
- Date: 2019
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/449433 , vital:74821 , https://doi.org/10.2989/00306525.2019.1568316
- Description: Seasonal altitudinal migration to lower altitudes including the coast has been ascribed to a number of forest birds, of which 14 species occur at Fort Fordyce Reserve in the Eastern Cape, South Africa. Based on our observations and ringing at this site (2007–2017), as well as concurrent data from the South African Bird Atlas Project (SABAP2), we suggest that in this region only three species, the African Dusky Flycatcher Muscicapa adusta, White-starred Robin Pogonocichla stellata and Barratt's Warbler Bradypterus barratti, are regular altitudinal migrants. For two other species, the Grey Cuckooshrike Coracina caesia and Yellow-throated Woodland Warbler Phylloscopus ruficapilla, local movements apparently occur, but these may take place within the coastal zone rather than between the coast and inland forests.
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Cape White-eyes in the Eastern Cape: plumage characters, survival, and movements
- Craig, Adrian J F K, Galpin, Mark D, Hulley, Patrick E, Tree, Anthony J
- Authors: Craig, Adrian J F K , Galpin, Mark D , Hulley, Patrick E , Tree, Anthony J
- Date: 2017
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/465358 , vital:76597 , https://journals.uct.ac.za/index.php/BO/article/view/423/464
- Description: Almost all our records of green-bellied Cape White-eyes are outside the breeding season, with a peak in winter. They possibly come from localities to the east of Grahamstown, Bathurst and Port Alfred, but we have no direct evidence of such movement, nor of altitudinal migration between coastal and inland sites. The higher frequency of green-bellied birds at the coastal ringing sites may suggest local movements within the coastal belt, or occasional coastwards movement by adjoining populations, which could also account for the diversity of flank colours recorded in a small proportion of the birds.
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- Authors: Craig, Adrian J F K , Galpin, Mark D , Hulley, Patrick E , Tree, Anthony J
- Date: 2017
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/465358 , vital:76597 , https://journals.uct.ac.za/index.php/BO/article/view/423/464
- Description: Almost all our records of green-bellied Cape White-eyes are outside the breeding season, with a peak in winter. They possibly come from localities to the east of Grahamstown, Bathurst and Port Alfred, but we have no direct evidence of such movement, nor of altitudinal migration between coastal and inland sites. The higher frequency of green-bellied birds at the coastal ringing sites may suggest local movements within the coastal belt, or occasional coastwards movement by adjoining populations, which could also account for the diversity of flank colours recorded in a small proportion of the birds.
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Comparative perch selection in Southern Fiscal Lanius collaris and Fiscal Flycatcher Sigelus silens at Amakhala Game Reserve, South Africa
- Daniels, Ryan J, Hulley, Patrick E, Craig, Adrian J F K
- Authors: Daniels, Ryan J , Hulley, Patrick E , Craig, Adrian J F K
- Date: 2017
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/449294 , vital:74809 , https://doi.org/10.2989/00306525.2016.1264496
- Description: The Southern Fiscal Lanius collaris and the Fiscal Flycatcher Sigelus silens are common, widespread and sympatric in much of southern Africa. They are similar in plumage and ecology, which may predispose them to competition and interspecific territorial aggression but this has not been tested to date. Here we tested for evidence of competition for perch space. At Amakhala Private Game Reserve, Eastern Cape, South Africa we monitored the occurrence and perch use of both species along transects. The birds do co-occur locally but there is evidence of small-scale spatial separation possibly a result of interspecific territoriality. Perch selection differed in respect of perch type but not perch height. Both species perched prominently in the majority of observations. Southern Fiscals make greater use of Searsia and Gymnosporia trees, whereas the Fiscal Flycatcher makes near-equal use of Vachellia karroo, Searsia and Gymnosporia trees. This may be an example of niche partitioning, though it remains unclear whether the birds actively compete for perch space, or if the separation is a product of different perch preferences, territoriality and the local plant community.
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- Authors: Daniels, Ryan J , Hulley, Patrick E , Craig, Adrian J F K
- Date: 2017
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/449294 , vital:74809 , https://doi.org/10.2989/00306525.2016.1264496
- Description: The Southern Fiscal Lanius collaris and the Fiscal Flycatcher Sigelus silens are common, widespread and sympatric in much of southern Africa. They are similar in plumage and ecology, which may predispose them to competition and interspecific territorial aggression but this has not been tested to date. Here we tested for evidence of competition for perch space. At Amakhala Private Game Reserve, Eastern Cape, South Africa we monitored the occurrence and perch use of both species along transects. The birds do co-occur locally but there is evidence of small-scale spatial separation possibly a result of interspecific territoriality. Perch selection differed in respect of perch type but not perch height. Both species perched prominently in the majority of observations. Southern Fiscals make greater use of Searsia and Gymnosporia trees, whereas the Fiscal Flycatcher makes near-equal use of Vachellia karroo, Searsia and Gymnosporia trees. This may be an example of niche partitioning, though it remains unclear whether the birds actively compete for perch space, or if the separation is a product of different perch preferences, territoriality and the local plant community.
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Gill Memorial Medal Address 2014 Reviewing the Red Bishop: the bird that introduced me to ornithology
- Authors: Craig, Adrian J F K
- Date: 2017
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/449401 , vital:74818 , https://www.tandfonline.com/doi/pdf/10.2989/00306525.2017.1302754
- Description: Euplectes (Craig 1992). Body mass, high at the start of the breeding season and then declining, increases again during this post-nuptial moult (Craig 1978). An initial analysis of the timing of moult estimated the duration of wing-moult at 110 d on the basis of birds recaptured during moult (Craig and Manson 1979a). Later, these data were reanalysed using new mathematical methods (Craig et al. 2001), which yielded a shorter estimate of 89 d for completion of wing-moult. Moult data from different regions of southern Africa, with samples of> 50 birds, showed striking differences with estimates of the duration of wing-moult ranging from 62 to 114 d (Oschadleus and Underhill 2006; Craig et al. 2010). However, the earlier conclusion that the start of moult in Zimbabwe was significantly later than in KwaZulu-Natal (Craig and Manson 1979a) was not supported when a larger sample of birds from the summer rainfall region was examined (Craig et al. 2010). Nine captive male Red Bishops kept under constant conditions of 14 h light: 10 h dark continued normal cycles of wing-moult, and showed cycles of testis enlargement and regression, but retained either partial or full nuptial plumage over a two-year period (Craig 1985). This suggests that circannual rhythms may play some role in the timing of moult, but further experimental investigations are required to confirm this idea.
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- Authors: Craig, Adrian J F K
- Date: 2017
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/449401 , vital:74818 , https://www.tandfonline.com/doi/pdf/10.2989/00306525.2017.1302754
- Description: Euplectes (Craig 1992). Body mass, high at the start of the breeding season and then declining, increases again during this post-nuptial moult (Craig 1978). An initial analysis of the timing of moult estimated the duration of wing-moult at 110 d on the basis of birds recaptured during moult (Craig and Manson 1979a). Later, these data were reanalysed using new mathematical methods (Craig et al. 2001), which yielded a shorter estimate of 89 d for completion of wing-moult. Moult data from different regions of southern Africa, with samples of> 50 birds, showed striking differences with estimates of the duration of wing-moult ranging from 62 to 114 d (Oschadleus and Underhill 2006; Craig et al. 2010). However, the earlier conclusion that the start of moult in Zimbabwe was significantly later than in KwaZulu-Natal (Craig and Manson 1979a) was not supported when a larger sample of birds from the summer rainfall region was examined (Craig et al. 2010). Nine captive male Red Bishops kept under constant conditions of 14 h light: 10 h dark continued normal cycles of wing-moult, and showed cycles of testis enlargement and regression, but retained either partial or full nuptial plumage over a two-year period (Craig 1985). This suggests that circannual rhythms may play some role in the timing of moult, but further experimental investigations are required to confirm this idea.
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Nectar feeding by weavers (Ploceidae) and their role as pollinators
- Authors: Craig, Adrian J F K
- Date: 2014
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/449445 , vital:74822 , https://doi.org/10.2989/00306525.2014.900828
- Description: Reviews of nectar-feeding by birds initially focused on specialist nectarivores and ignored the role that more generalist feeders may play in plant pollination. Recent work has emphasised the range of bird species, both specialist and opportunistic, that feed on nectar. In this review, I collate published information on nectar-feeding by weavers, highlight known weaver–plant relationships, and suggest areas for future research. There are published records of nectar feeding for Plocepasser superciliosus, Amblyospiza albifrons, Anaplectes rubriceps, two Quelea spp., four Euplectes spp., all six Foudia spp., two Malimbus spp. and 22 Ploceus spp. To date, there have been no unambiguous reports of other genera feeding on nectar. The role of Ploceus species as pollinators of Strelitzia reginae, proposed by ornithologists decades ago, has recently been confirmed by botanists. Current studies of Aloe species in South Africa suggest that opportunistic avian nectarivores such as ploceids may be the chief pollinators of bird-pollinated plants in this genus, whereas specialist nectar feeders (sunbirds) may be ‘nectar robbers’ in many cases. Particularly for winter-flowering plants, weaver species are potential pollinators, but exclusion experiments are needed to establish their role, while the dietary importance of nectar, and its impact on the birds’ physiology, has not been critically studied.
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- Authors: Craig, Adrian J F K
- Date: 2014
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/449445 , vital:74822 , https://doi.org/10.2989/00306525.2014.900828
- Description: Reviews of nectar-feeding by birds initially focused on specialist nectarivores and ignored the role that more generalist feeders may play in plant pollination. Recent work has emphasised the range of bird species, both specialist and opportunistic, that feed on nectar. In this review, I collate published information on nectar-feeding by weavers, highlight known weaver–plant relationships, and suggest areas for future research. There are published records of nectar feeding for Plocepasser superciliosus, Amblyospiza albifrons, Anaplectes rubriceps, two Quelea spp., four Euplectes spp., all six Foudia spp., two Malimbus spp. and 22 Ploceus spp. To date, there have been no unambiguous reports of other genera feeding on nectar. The role of Ploceus species as pollinators of Strelitzia reginae, proposed by ornithologists decades ago, has recently been confirmed by botanists. Current studies of Aloe species in South Africa suggest that opportunistic avian nectarivores such as ploceids may be the chief pollinators of bird-pollinated plants in this genus, whereas specialist nectar feeders (sunbirds) may be ‘nectar robbers’ in many cases. Particularly for winter-flowering plants, weaver species are potential pollinators, but exclusion experiments are needed to establish their role, while the dietary importance of nectar, and its impact on the birds’ physiology, has not been critically studied.
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Regional patterns in moult and sexual dimorphism of adult Southern Red Bishops Euplectes orix in southern Africa
- Craig, Adrian J F K, Bonnevie, Bo T, Oschadleus, Hans-Dieter
- Authors: Craig, Adrian J F K , Bonnevie, Bo T , Oschadleus, Hans-Dieter
- Date: 2010
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/449503 , vital:74826 , https://doi.org/10.2989/00306525.2010.488357
- Description: Using the SAFRING database and the Underhill-Zucchini model of primary moult, we analysed the timing of wing moult in Southern Red Bishops Euplectes orix in relation to sex and geographical region. Birds from the winter rainfall region in the south-western sector of the Western Cape start the annual moult more than two months before any other population, but there were no significant differences in starting date within the summer rainfall region. There were striking differences in the estimates of moult duration (62–114 d), which did not follow a consistent pattern in relation to sex or geography; annual variation within a region may be an additional factor. Throughout southern Africa, both sexes showed a trend for longer-winged birds to take more time to complete their moult. We suggest that sex, geographical area and possible annual environmental variations may all influence the timing of moult in local populations. In this sexually dimorphic species, males are consistently longer-winged and heavier than females.
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- Authors: Craig, Adrian J F K , Bonnevie, Bo T , Oschadleus, Hans-Dieter
- Date: 2010
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/449503 , vital:74826 , https://doi.org/10.2989/00306525.2010.488357
- Description: Using the SAFRING database and the Underhill-Zucchini model of primary moult, we analysed the timing of wing moult in Southern Red Bishops Euplectes orix in relation to sex and geographical region. Birds from the winter rainfall region in the south-western sector of the Western Cape start the annual moult more than two months before any other population, but there were no significant differences in starting date within the summer rainfall region. There were striking differences in the estimates of moult duration (62–114 d), which did not follow a consistent pattern in relation to sex or geography; annual variation within a region may be an additional factor. Throughout southern Africa, both sexes showed a trend for longer-winged birds to take more time to complete their moult. We suggest that sex, geographical area and possible annual environmental variations may all influence the timing of moult in local populations. In this sexually dimorphic species, males are consistently longer-winged and heavier than females.
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Timing of moult and breeding in the Cape White-eye, Zosterops pallidus, from three different geographical regions in South Africa
- Hulley, Patrick E, Craig, Adrian J F K, Underhill, George D, Bonnevie, Bo T, Nuttall, R J, De Swardt, D H
- Authors: Hulley, Patrick E , Craig, Adrian J F K , Underhill, George D , Bonnevie, Bo T , Nuttall, R J , De Swardt, D H
- Date: 2004
- Subjects: To be catalogued
- Language: English
- Type: article
- Identifier: http://hdl.handle.net/10962/465570 , vital:76621 , https://doi.org/10.1071/MU03055
- Description: Cape White-eyes are widespread in South Africa, occurring in different climatic regions. We analysed primary moult data for large samples of this species from three geographical regions. There were no apparent long-term changes in duration or timing of moult during the nine years that the Western Cape results were collected, but sites within this region had different mean starting dates for primary moult. The Eastern Cape and Free State birds began moult about a month later than those in the Western Cape. This correlated well with the earlier breeding season in the Western Cape, and there was no evidence of overlap between moult and breeding. Mean primary moult duration was not significantly different among the sites or regions, and may be a species-specific trait. There was no evidence of regular long-distance movements in this species.
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- Authors: Hulley, Patrick E , Craig, Adrian J F K , Underhill, George D , Bonnevie, Bo T , Nuttall, R J , De Swardt, D H
- Date: 2004
- Subjects: To be catalogued
- Language: English
- Type: article
- Identifier: http://hdl.handle.net/10962/465570 , vital:76621 , https://doi.org/10.1071/MU03055
- Description: Cape White-eyes are widespread in South Africa, occurring in different climatic regions. We analysed primary moult data for large samples of this species from three geographical regions. There were no apparent long-term changes in duration or timing of moult during the nine years that the Western Cape results were collected, but sites within this region had different mean starting dates for primary moult. The Eastern Cape and Free State birds began moult about a month later than those in the Western Cape. This correlated well with the earlier breeding season in the Western Cape, and there was no evidence of overlap between moult and breeding. Mean primary moult duration was not significantly different among the sites or regions, and may be a species-specific trait. There was no evidence of regular long-distance movements in this species.
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Moult, breeding season, mass, wing length, and dispersal in Cape Robins (Cossypha caffra) and Olive Thrushes (Turdus olivaceus) results from mist-netting garden birds
- Bonnevie, Bo T, Craig, Adrian J F K, Hulley, Patrick E, Underhill, George D
- Authors: Bonnevie, Bo T , Craig, Adrian J F K , Hulley, Patrick E , Underhill, George D
- Date: 2003
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/465420 , vital:76606 , https://doi.org/10.2989/00306520309485372
- Description: We compared a data set from the Western Cape, South Africa (GDU, n = 170 Olive Thrushes (Turdus olivaceus), n = 475 Cape Robins (Cossypha caffra)) with our captures in the Eastern Cape, South Africa (n = 197 Olive Thrushes, n = 203 Cape Robins). In both regions Olive Thrushes began moult in December-January, while wing-moult lasted for 89 days in the Western Cape compared to 53 days in the Eastern Cape. Cape Robins began moult in early November in the Western Cape, early January in the Eastern Cape and again the duration of wing-moult was longer in the Western Cape (64 days) than in the Eastern Cape (50 days). For both species the start of moult coincided with the end of the breeding season. Cape Robins were heavier and longer-winged in the Western Cape than in the Eastern Cape. There was no significant difference in mean mass or mean wing length of the Olive Thrush between the two provinces. Both ringing and atlas data suggest that Cape Robins are relatively more common than Olive Thrushes in the Western Cape, but not in the Eastern Cape. In the Eastern Cape we observed colour-ringed robins (n = 2) and thrushes (n = 2) on their breeding territory in all months of the year, suggesting that some individuals of both species are strongly resident.
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- Authors: Bonnevie, Bo T , Craig, Adrian J F K , Hulley, Patrick E , Underhill, George D
- Date: 2003
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/465420 , vital:76606 , https://doi.org/10.2989/00306520309485372
- Description: We compared a data set from the Western Cape, South Africa (GDU, n = 170 Olive Thrushes (Turdus olivaceus), n = 475 Cape Robins (Cossypha caffra)) with our captures in the Eastern Cape, South Africa (n = 197 Olive Thrushes, n = 203 Cape Robins). In both regions Olive Thrushes began moult in December-January, while wing-moult lasted for 89 days in the Western Cape compared to 53 days in the Eastern Cape. Cape Robins began moult in early November in the Western Cape, early January in the Eastern Cape and again the duration of wing-moult was longer in the Western Cape (64 days) than in the Eastern Cape (50 days). For both species the start of moult coincided with the end of the breeding season. Cape Robins were heavier and longer-winged in the Western Cape than in the Eastern Cape. There was no significant difference in mean mass or mean wing length of the Olive Thrush between the two provinces. Both ringing and atlas data suggest that Cape Robins are relatively more common than Olive Thrushes in the Western Cape, but not in the Eastern Cape. In the Eastern Cape we observed colour-ringed robins (n = 2) and thrushes (n = 2) on their breeding territory in all months of the year, suggesting that some individuals of both species are strongly resident.
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Song sharing by neighbourhood groups of territorial male Blackeyed Bulbuls
- Lloyd, Penn, Hulley, Patrick E, Craig, Adrian J F K
- Authors: Lloyd, Penn , Hulley, Patrick E , Craig, Adrian J F K
- Date: 1999
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/447841 , vital:74678 , https://doi.org/10.1080/00306525.1999.9634238
- Description: The territorial song of the Blackeyed Bulbul Pycnonotus barbatus is described for a population followed over two breeding seasons in suburban Grahamstown, South Africa. The Blackeyed Bulbul has a discrete and highly structured system of phrase sharing by neighbourhood groups of males. The most common repertoire size is five phrases (mean 5.5; range 2–9). In a temporally-stable song population, individual phrases are shared independently by discrete clusters of males. Neighbours show a strong tendency to share phrase types (but rarely whole repertoires), with overall song similarity decreasing rapidly with increasing distance between birds. This species is an ideal candidate for testing hypotheses concerning the adaptive value of song sharing by neighbourhood groups.
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- Authors: Lloyd, Penn , Hulley, Patrick E , Craig, Adrian J F K
- Date: 1999
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/447841 , vital:74678 , https://doi.org/10.1080/00306525.1999.9634238
- Description: The territorial song of the Blackeyed Bulbul Pycnonotus barbatus is described for a population followed over two breeding seasons in suburban Grahamstown, South Africa. The Blackeyed Bulbul has a discrete and highly structured system of phrase sharing by neighbourhood groups of males. The most common repertoire size is five phrases (mean 5.5; range 2–9). In a temporally-stable song population, individual phrases are shared independently by discrete clusters of males. Neighbours show a strong tendency to share phrase types (but rarely whole repertoires), with overall song similarity decreasing rapidly with increasing distance between birds. This species is an ideal candidate for testing hypotheses concerning the adaptive value of song sharing by neighbourhood groups.
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The annual cycle of wing‐moult and breeding in the Wattled Starling Creatophora cinerea
- Authors: Craig, Adrian J F K
- Date: 1996
- Subjects: To be catalogued
- Language: English
- Type: article
- Identifier: http://hdl.handle.net/10962/465496 , vital:76614 , https://doi.org/10.1111/j.1474-919X.1996.tb08063.x
- Description: Moult, breeding and seasonal occurrence of the Wattled Starling Creatophora cinerea throughout its range in Africa are reviewed based on data from museum specimens and the published literature. Neither moult nor breeding follows a rigid seasonal pattern, although there are some regional differences, and overlap between moult and breeding is unlikely. The regular occurrence of interrupted wing‐moult may be associated with nomadic movements rather than opportunistic breeding.
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- Authors: Craig, Adrian J F K
- Date: 1996
- Subjects: To be catalogued
- Language: English
- Type: article
- Identifier: http://hdl.handle.net/10962/465496 , vital:76614 , https://doi.org/10.1111/j.1474-919X.1996.tb08063.x
- Description: Moult, breeding and seasonal occurrence of the Wattled Starling Creatophora cinerea throughout its range in Africa are reviewed based on data from museum specimens and the published literature. Neither moult nor breeding follows a rigid seasonal pattern, although there are some regional differences, and overlap between moult and breeding is unlikely. The regular occurrence of interrupted wing‐moult may be associated with nomadic movements rather than opportunistic breeding.
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The distribution of the Wattled Starling in southern Africa
- Authors: Craig, Adrian J F K
- Date: 1992
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/447896 , vital:74682 , https://doi.org/10.1080/00306525.1992.9634180
- Description: Dated distribution records of the Wattled Starling Creatophora cinerea have been assembled from the literature, museum specimens, atlas records, and other unpublished observations. The bulk of these records are from the period 1980–89. Breeding records are sparse, but breeding appears to be seasonal in the winter rainfall area. In summer rainfall areas nesting occurs from spring through to autumn, dependent on the presence of abundant insects. In most areas winter records (June to August) predominate, but in the eastern lowveld areas of South Africa Wattled Starlings are recorded most often in spring and summer. The species is correctly described as nomadic, and the pattern of occurrence does not suggest regular migration.
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- Authors: Craig, Adrian J F K
- Date: 1992
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/447896 , vital:74682 , https://doi.org/10.1080/00306525.1992.9634180
- Description: Dated distribution records of the Wattled Starling Creatophora cinerea have been assembled from the literature, museum specimens, atlas records, and other unpublished observations. The bulk of these records are from the period 1980–89. Breeding records are sparse, but breeding appears to be seasonal in the winter rainfall area. In summer rainfall areas nesting occurs from spring through to autumn, dependent on the presence of abundant insects. In most areas winter records (June to August) predominate, but in the eastern lowveld areas of South Africa Wattled Starlings are recorded most often in spring and summer. The species is correctly described as nomadic, and the pattern of occurrence does not suggest regular migration.
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Histological basis of age-related changes in iris color in the African Pied Starling (Spreo bicolor)
- Sweijd, Neville, Craig, Adrian J F K
- Authors: Sweijd, Neville , Craig, Adrian J F K
- Date: 1991
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/465393 , vital:76600 , http://www.jstor.org/stable/4088047
- Description: Juvenile African Pied Starlings (Spreo bicolor) have a dark brown iris, but after the first year iris color changes progressively until adult birds have a creamy-white iris. Using light and electron microscopy, we found that the pigment epithelium of the iris remains pigmented, while changes occur in the pigmentation of the anterior border layer and the stroma of the subadult and adult iris. In the juvenile iris the anterior border layer is darkly pigmented, but in the subadult iris this pigmentation is lost progressively, while pigment granules are deposited in the stroma. In adults, the stroma is heavily pigmented with a solid refractory pigment, and the anterior border layer is clear.
- Full Text:
Histological basis of age-related changes in iris color in the African Pied Starling (Spreo bicolor)
- Authors: Sweijd, Neville , Craig, Adrian J F K
- Date: 1991
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/465393 , vital:76600 , http://www.jstor.org/stable/4088047
- Description: Juvenile African Pied Starlings (Spreo bicolor) have a dark brown iris, but after the first year iris color changes progressively until adult birds have a creamy-white iris. Using light and electron microscopy, we found that the pigment epithelium of the iris remains pigmented, while changes occur in the pigmentation of the anterior border layer and the stroma of the subadult and adult iris. In the juvenile iris the anterior border layer is darkly pigmented, but in the subadult iris this pigmentation is lost progressively, while pigment granules are deposited in the stroma. In adults, the stroma is heavily pigmented with a solid refractory pigment, and the anterior border layer is clear.
- Full Text:
The timing of breeding and wing‐moult of four African Sturnidae
- Authors: Craig, Adrian J F K
- Date: 1983
- Subjects: To be catalogued
- Language: English
- Type: article
- Identifier: http://hdl.handle.net/10962/465549 , vital:76619 , https://doi.org/10.1111/j.1474-919X.1983.tb03120.x
- Description: Wing‐moult of the Cape Glossy Starling, Red‐winged Starling, Pale‐winged Starling and Pied Starling was examined primarily from speci-mens in southern African museums. Breeding data were obtained from nest record cards. The Cape Glossy Starling breeds from October to March, with the moult period from December to May. There is no evi-dence of moult‐breeding overlap in individual birds. The Red‐winged Starling breeds from September to March, while the moult takes place between November and April, overlapping with the second broods. The Pale‐winged Starling breeds from October to April and moults between November and May. The Pied Starling moults between November and April, while breeding varies regionally, occurring concurrently with moulting in some areas.
- Full Text:
- Authors: Craig, Adrian J F K
- Date: 1983
- Subjects: To be catalogued
- Language: English
- Type: article
- Identifier: http://hdl.handle.net/10962/465549 , vital:76619 , https://doi.org/10.1111/j.1474-919X.1983.tb03120.x
- Description: Wing‐moult of the Cape Glossy Starling, Red‐winged Starling, Pale‐winged Starling and Pied Starling was examined primarily from speci-mens in southern African museums. Breeding data were obtained from nest record cards. The Cape Glossy Starling breeds from October to March, with the moult period from December to May. There is no evi-dence of moult‐breeding overlap in individual birds. The Red‐winged Starling breeds from September to March, while the moult takes place between November and April, overlapping with the second broods. The Pale‐winged Starling breeds from October to April and moults between November and May. The Pied Starling moults between November and April, while breeding varies regionally, occurring concurrently with moulting in some areas.
- Full Text:
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