Turbidity-induced changes in feeding strategies of fish in estuaries
- Hecht, Thomas, Van der Lingen, C D
- Authors: Hecht, Thomas , Van der Lingen, C D
- Date: 1992
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/446960 , vital:74573 , https://hdl.handle.net/10520/AJA00445096_644
- Description: The aim of this study was to determine the effect of turbidity on the feeding strategies of fish in estuaries. Three species representing different feeding guilds were selected for the investigation. These were Elops machnata (representative piscivore), Pomadasys commefsonnii (a macrobenthivore) and Athefina breviceps (a planktivore). The stomach contents of these fish were examined from a clear and a turbid estuary and some experimental work was carried out on A. brevic8ps to test the hypothesis that turbidity affects feeding behaviour. Turbidity was found to have no effect on size selection of prey, but feeding rate, particularly of visual predators, was reduced at higher turbidity levels. This was caused by a decrease in the reactive distance of the fish. It would appear that in order to optimize the aquisition of food under different turbidity conditions fishes have the ability to change their feeding strategies. Visual predators are more affected by turbidity than are macrobenthic feeders.
- Full Text:
- Date Issued: 1992
- Authors: Hecht, Thomas , Van der Lingen, C D
- Date: 1992
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/446960 , vital:74573 , https://hdl.handle.net/10520/AJA00445096_644
- Description: The aim of this study was to determine the effect of turbidity on the feeding strategies of fish in estuaries. Three species representing different feeding guilds were selected for the investigation. These were Elops machnata (representative piscivore), Pomadasys commefsonnii (a macrobenthivore) and Athefina breviceps (a planktivore). The stomach contents of these fish were examined from a clear and a turbid estuary and some experimental work was carried out on A. brevic8ps to test the hypothesis that turbidity affects feeding behaviour. Turbidity was found to have no effect on size selection of prey, but feeding rate, particularly of visual predators, was reduced at higher turbidity levels. This was caused by a decrease in the reactive distance of the fish. It would appear that in order to optimize the aquisition of food under different turbidity conditions fishes have the ability to change their feeding strategies. Visual predators are more affected by turbidity than are macrobenthic feeders.
- Full Text:
- Date Issued: 1992
An approach to the evaluation of microcomputer operating systems with respect to real-time issues
- Authors: Wells, George C
- Date: 1991
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/430484 , vital:72694 , https://doi.org/10.1016/0165-6074(91)90014-K
- Description: This paper gives an overview of the approach used for the assessment of several operating systems for microcomputers. The operating systems are all commercial products and cover a spectrum ranging from general purpose operating systems to small, real-time operating systems. The criteria used for the evaluation are discussed and the approach used is discussed in detail. The results of the evaluation are not discussed in this paper.
- Full Text:
- Date Issued: 1991
- Authors: Wells, George C
- Date: 1991
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/430484 , vital:72694 , https://doi.org/10.1016/0165-6074(91)90014-K
- Description: This paper gives an overview of the approach used for the assessment of several operating systems for microcomputers. The operating systems are all commercial products and cover a spectrum ranging from general purpose operating systems to small, real-time operating systems. The criteria used for the evaluation are discussed and the approach used is discussed in detail. The results of the evaluation are not discussed in this paper.
- Full Text:
- Date Issued: 1991
The Behaviour Of Palewinged Starlings And A Comparison With Other Onychognathvs Species
- Craig, Adrian J F K, Hulley, Patrick E, Walter, Grenville H
- Authors: Craig, Adrian J F K , Hulley, Patrick E , Walter, Grenville H
- Date: 1991
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/447868 , vital:74680 , https://doi.org/10.1080/00306525.1991.9639648
- Description: Pairs of Palewinged Starlings associate throughout the year and roost at the nest sites. Flock sizes are generally small, even during the non-breeding season. Allofeeding and allopreening have not been recorded. Wing displays emphasize the white region of the primaries. The territory appears to be restricted to the nest site. Interspecific aggression occurred between Redwinged and Palewinged Starlings, and was also directed at other Ed species frequenting the cliff. A form of ceremonial gathering occurs re in Palewinged Starlings. A review of the literature suggests that on behavioural grounds the Palewinged Starling shows no close affinity to the Redwinged Starfng or to any other member of the genus.
- Full Text:
- Date Issued: 1991
- Authors: Craig, Adrian J F K , Hulley, Patrick E , Walter, Grenville H
- Date: 1991
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/447868 , vital:74680 , https://doi.org/10.1080/00306525.1991.9639648
- Description: Pairs of Palewinged Starlings associate throughout the year and roost at the nest sites. Flock sizes are generally small, even during the non-breeding season. Allofeeding and allopreening have not been recorded. Wing displays emphasize the white region of the primaries. The territory appears to be restricted to the nest site. Interspecific aggression occurred between Redwinged and Palewinged Starlings, and was also directed at other Ed species frequenting the cliff. A form of ceremonial gathering occurs re in Palewinged Starlings. A review of the literature suggests that on behavioural grounds the Palewinged Starling shows no close affinity to the Redwinged Starfng or to any other member of the genus.
- Full Text:
- Date Issued: 1991
Aspects of Shakespeare in post-colonial Africa
- Authors: Wright, Laurence
- Date: 1990
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/455614 , vital:75443 , https://hdl.handle.net/10520/AJA1011582X_182
- Description: Two views capture in cameo the most obvious conflict over Shake-speare's presence in post-colonial Africa. The late Okot p'Bitek, when newly appointed as Director of Uganda's National Theatre, set tradi-tional drummers to play outside the building; he was, in David Rubadiri's words," challenging... the British Council, which thought it had exclusive rights to put Shakespeare there all the time instead of getting the ordi-nary people... to come and see local plays".
- Full Text:
- Date Issued: 1990
- Authors: Wright, Laurence
- Date: 1990
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/455614 , vital:75443 , https://hdl.handle.net/10520/AJA1011582X_182
- Description: Two views capture in cameo the most obvious conflict over Shake-speare's presence in post-colonial Africa. The late Okot p'Bitek, when newly appointed as Director of Uganda's National Theatre, set tradi-tional drummers to play outside the building; he was, in David Rubadiri's words," challenging... the British Council, which thought it had exclusive rights to put Shakespeare there all the time instead of getting the ordi-nary people... to come and see local plays".
- Full Text:
- Date Issued: 1990
Mdledle's Xhosa translation of Julius Caesar
- Authors: Mtuze, Peter
- Date: 1990
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/457804 , vital:75680 , https://hdl.handle.net/10520/AJA1011582X_184
- Description: Although Xhosa literature could not escape the influence of Western literature over the decades, only a handful of literary works has been translated into Xhosa. Tiyo Soga's pioneering translation of Bunyan's Pilgrim's Progress, Uhambo lomhambi, appeared in 1867. Bunyan's book was either translated, adapted or parodied by most of the emerg-ing African literatures in South Africa. Then followed a long wait until 1947, when SEK Mqhayi translated GB Hobson's Kees van die Kalaha-ri as Adonisi wasentlango. As was the case with other African lan-guages, the'50s and early'60s saw the hey-day of translations into Eng-lish. Booker Washington's Up from Slavery was translated as Uku-phakama ukusuka ebukhobokeni by IIR Iolobe in 1951, while the first of BB Mdlede's translations of Shakespeare, UJulius Caesar, appeared in 1957, along with Iolobe's translation of W. Bonsel's Maja die bei (UMa-ya: Amahla-ndinyuka enyosl) and D. Lupuwana's translation of Khwane by P. Cook.
- Full Text:
- Date Issued: 1990
- Authors: Mtuze, Peter
- Date: 1990
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/457804 , vital:75680 , https://hdl.handle.net/10520/AJA1011582X_184
- Description: Although Xhosa literature could not escape the influence of Western literature over the decades, only a handful of literary works has been translated into Xhosa. Tiyo Soga's pioneering translation of Bunyan's Pilgrim's Progress, Uhambo lomhambi, appeared in 1867. Bunyan's book was either translated, adapted or parodied by most of the emerg-ing African literatures in South Africa. Then followed a long wait until 1947, when SEK Mqhayi translated GB Hobson's Kees van die Kalaha-ri as Adonisi wasentlango. As was the case with other African lan-guages, the'50s and early'60s saw the hey-day of translations into Eng-lish. Booker Washington's Up from Slavery was translated as Uku-phakama ukusuka ebukhobokeni by IIR Iolobe in 1951, while the first of BB Mdlede's translations of Shakespeare, UJulius Caesar, appeared in 1957, along with Iolobe's translation of W. Bonsel's Maja die bei (UMa-ya: Amahla-ndinyuka enyosl) and D. Lupuwana's translation of Khwane by P. Cook.
- Full Text:
- Date Issued: 1990
Othello and the Narrative of Africa
- Authors: Van Wyk Smith, Malvern
- Date: 1990
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/457457 , vital:75639 , https://hdl.handle.net/10520/AJA1011582X_181
- Description: Although Othello is where I want to start and where I hope to end, my proper aim is the more general one of Africa as seen through Elizabe-than eyes. I shall use a particular moment in the playas a crux upon which to develop a broad-ranging examination of what Elizabethans knew about Africa, or what they thought they knew about Africa, or, bet-ter still, how they understood what they thought they knew about Africa. The incident is Othello's appearance before the Venetian court where, accused by Desdemona's father that he had suborned her judgement with" charms... conjuration... and mighty magic"(1.3. 91-92), Othello proposes to unfold" a round unvarnished tale" to prove his veracity, his nobility and, most importantly, his common humanity with the Vene-tians. The speech contains such" round unvarnished" matters as the cannibals that each other eat, The anthropophagi, and men whose heads Do grow beneath their shoulders.
- Full Text:
- Date Issued: 1990
- Authors: Van Wyk Smith, Malvern
- Date: 1990
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/457457 , vital:75639 , https://hdl.handle.net/10520/AJA1011582X_181
- Description: Although Othello is where I want to start and where I hope to end, my proper aim is the more general one of Africa as seen through Elizabe-than eyes. I shall use a particular moment in the playas a crux upon which to develop a broad-ranging examination of what Elizabethans knew about Africa, or what they thought they knew about Africa, or, bet-ter still, how they understood what they thought they knew about Africa. The incident is Othello's appearance before the Venetian court where, accused by Desdemona's father that he had suborned her judgement with" charms... conjuration... and mighty magic"(1.3. 91-92), Othello proposes to unfold" a round unvarnished tale" to prove his veracity, his nobility and, most importantly, his common humanity with the Vene-tians. The speech contains such" round unvarnished" matters as the cannibals that each other eat, The anthropophagi, and men whose heads Do grow beneath their shoulders.
- Full Text:
- Date Issued: 1990
A review of the biology of the Blackbellied Starling and other African forest starlings
- Authors: Craig, Adrian J F K
- Date: 1989
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/447730 , vital:74670 , https://doi.org/10.1080/00306525.1989.9639610
- Description: The Blackbellied Starling Lamprotornis corruscus is the only true forest starling in southern Africa. At the southern end of its coastal range it is an irregular visitor, and it may move according to food availability. The limited data on breeding, moult and seasonal occurrence are discussed. Only two subspecies are recognised. A brief survey of the 12 African starlings of evergreen forests shows that little is known about their basic biology or their role as highly mobile frugivores.
- Full Text:
- Date Issued: 1989
- Authors: Craig, Adrian J F K
- Date: 1989
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/447730 , vital:74670 , https://doi.org/10.1080/00306525.1989.9639610
- Description: The Blackbellied Starling Lamprotornis corruscus is the only true forest starling in southern Africa. At the southern end of its coastal range it is an irregular visitor, and it may move according to food availability. The limited data on breeding, moult and seasonal occurrence are discussed. Only two subspecies are recognised. A brief survey of the 12 African starlings of evergreen forests shows that little is known about their basic biology or their role as highly mobile frugivores.
- Full Text:
- Date Issued: 1989
Nesting of sympatric redwinged and pale winged starlings
- Craig, Adrian J F K, Hulley, Patrick E, Walter, Grenville H
- Authors: Craig, Adrian J F K , Hulley, Patrick E , Walter, Grenville H
- Date: 1989
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/447827 , vital:74677 , https://doi.org/10.1080/00306525.1989.9634513
- Description: Observations were made over four breeding seasons at Cradock, South Africa, where Redwinged Starlings Onychognathus morio and Palewinged Starlings O. nabouroup nest on the same cliffs. Nests were not accessible, and the stage of breeding was determined by the behaviour of the birds. Both species reuse the same nest sites, and only the females incubate, but both sexes feed the young. The timing of breedingMaybe more variable in the Palewinged Starling. A review of the available data on nest site selection and nest construction shows apparent species-specific differences: Redwinged Starlings usually nest on ledges, often on buildings, and use mud in the nest base; Palewinged Starlings favour vertical crevices, and do not use mud.
- Full Text:
- Date Issued: 1989
- Authors: Craig, Adrian J F K , Hulley, Patrick E , Walter, Grenville H
- Date: 1989
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/447827 , vital:74677 , https://doi.org/10.1080/00306525.1989.9634513
- Description: Observations were made over four breeding seasons at Cradock, South Africa, where Redwinged Starlings Onychognathus morio and Palewinged Starlings O. nabouroup nest on the same cliffs. Nests were not accessible, and the stage of breeding was determined by the behaviour of the birds. Both species reuse the same nest sites, and only the females incubate, but both sexes feed the young. The timing of breedingMaybe more variable in the Palewinged Starling. A review of the available data on nest site selection and nest construction shows apparent species-specific differences: Redwinged Starlings usually nest on ledges, often on buildings, and use mud in the nest base; Palewinged Starlings favour vertical crevices, and do not use mud.
- Full Text:
- Date Issued: 1989
Shakespeare, Webster and the Moriturus Lyric in Renaissance England
- Authors: Gouws, John S
- Date: 1989
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/457869 , vital:75686 , https://hdl.handle.net/10520/AJA1011582X_75
- Description: It is perhaps a commonplace that the dying will register their experience as a lingering on a threshold, but it is remarkable, in the first place, to record that awareness in a poem, and, in the second place, to insist that the poem be placed at the end of the book. As I hope to show in the course of this discussion, the notion of writing a poem in the face of imminent death is not uncommon in the Renaissance; in fact, the act of doing so is one of the manifestations of a" good death", a mode of" self-fashioning" not restricted to poets. What is unusual and innovative about the Waller example is the inauguration of the self-consciously placed poem in the collected works of a poet, an act which leads inevi-tably to the most famous instance, Tennyson's" Crossing the Bar". Two Emily Dickinson poems suggest that in the nineteenth century the genre was sufficiently established to invite variant forms. In" I heard a Fly buzz-when I died-", the speaker recounts the experience of diminishing consciousness, and in" Because I could not stop for Death-" she crosses the threshold into the next world.'The latler poem of course al-so makes use of the" Death and the Maiden"(the rape of Persephone) motif, and so goes well beyond what can be regarded as a true moritu-rus lyric.
- Full Text:
- Date Issued: 1989
- Authors: Gouws, John S
- Date: 1989
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/457869 , vital:75686 , https://hdl.handle.net/10520/AJA1011582X_75
- Description: It is perhaps a commonplace that the dying will register their experience as a lingering on a threshold, but it is remarkable, in the first place, to record that awareness in a poem, and, in the second place, to insist that the poem be placed at the end of the book. As I hope to show in the course of this discussion, the notion of writing a poem in the face of imminent death is not uncommon in the Renaissance; in fact, the act of doing so is one of the manifestations of a" good death", a mode of" self-fashioning" not restricted to poets. What is unusual and innovative about the Waller example is the inauguration of the self-consciously placed poem in the collected works of a poet, an act which leads inevi-tably to the most famous instance, Tennyson's" Crossing the Bar". Two Emily Dickinson poems suggest that in the nineteenth century the genre was sufficiently established to invite variant forms. In" I heard a Fly buzz-when I died-", the speaker recounts the experience of diminishing consciousness, and in" Because I could not stop for Death-" she crosses the threshold into the next world.'The latler poem of course al-so makes use of the" Death and the Maiden"(the rape of Persephone) motif, and so goes well beyond what can be regarded as a true moritu-rus lyric.
- Full Text:
- Date Issued: 1989
The application of real-time design techniques to simulation
- Authors: Wells, George C
- Date: 1989
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/430541 , vital:72698 , 10.1049/sej.1989.0040
- Description: The paper discusses the application of the Ward and Mellor structured development techniques for real-time systems to the field of simulation. The tools and heuristics used by Ward and Mellor are extended to provide a useful approach to the design of real-time simulations. This is illustrated by the example of a real-time simulation of a manufacturing plant and process control system.
- Full Text:
- Date Issued: 1989
- Authors: Wells, George C
- Date: 1989
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/430541 , vital:72698 , 10.1049/sej.1989.0040
- Description: The paper discusses the application of the Ward and Mellor structured development techniques for real-time systems to the field of simulation. The tools and heuristics used by Ward and Mellor are extended to provide a useful approach to the design of real-time simulations. This is illustrated by the example of a real-time simulation of a manufacturing plant and process control system.
- Full Text:
- Date Issued: 1989
Jacobean psychiatry: Edgar's curative stratagems
- Authors: Butler, Guy F
- Date: 1988
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/457724 , vital:75674 , https://hdl.handle.net/10520/AJA1011582X_52
- Description: In the sixteenth and seventeenth centuries despair is seen as the abandonment of hope, a sinful refusal to practise one of the cardinal christian virtues. To be without hope in the world is to enter a mental prison in which life becomes loathsome and death desirable. It is the common prelude to suicide, an act condemned by state and church alike. To abandon hope in God's power to forgive sins, or to lose faith in the ultimate justice of Heaven, was to be guilty of blasphemy. The sui-cide, in rejecting God, sent himself to hell.
- Full Text:
- Date Issued: 1988
- Authors: Butler, Guy F
- Date: 1988
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/457724 , vital:75674 , https://hdl.handle.net/10520/AJA1011582X_52
- Description: In the sixteenth and seventeenth centuries despair is seen as the abandonment of hope, a sinful refusal to practise one of the cardinal christian virtues. To be without hope in the world is to enter a mental prison in which life becomes loathsome and death desirable. It is the common prelude to suicide, an act condemned by state and church alike. To abandon hope in God's power to forgive sins, or to lose faith in the ultimate justice of Heaven, was to be guilty of blasphemy. The sui-cide, in rejecting God, sent himself to hell.
- Full Text:
- Date Issued: 1988
Shakespeare and the bomber pilot: A reply to Colin Gardner
- Authors: Wright, Laurence
- Date: 1988
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/455734 , vital:75452 , https://hdl.handle.net/10520/AJA1011582X_59
- Description: I want to start at what may seem an unfair distance from the kind of view Colin Gardner has put forward. Early in 1947 the date is signifi-cant-a group of science students at Cambridge asked that some lec-tures on English Literature be organised for their special benefit. TR Henn responded and versions of his lectures were later published as The Apple and the Spectroscope (1951). In the book, Henn records the reaction of one of his students to Macbeth's speech at 1.7. 16-25: Be-sides, this Duncan Hath borne his faculties so meek, hath been So clear in his great office, that his virtues Will plead like angels, trumpet-tongu'd against The deep damnation of his taking off; And pity, like a naked new-born babe, Striding the blast, or heaven's cherubin, hors'd U pan the sightless couriers of the air, Shall blow the horrid deed in every eye, That tears shall drown the wind.
- Full Text:
- Date Issued: 1988
- Authors: Wright, Laurence
- Date: 1988
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/455734 , vital:75452 , https://hdl.handle.net/10520/AJA1011582X_59
- Description: I want to start at what may seem an unfair distance from the kind of view Colin Gardner has put forward. Early in 1947 the date is signifi-cant-a group of science students at Cambridge asked that some lec-tures on English Literature be organised for their special benefit. TR Henn responded and versions of his lectures were later published as The Apple and the Spectroscope (1951). In the book, Henn records the reaction of one of his students to Macbeth's speech at 1.7. 16-25: Be-sides, this Duncan Hath borne his faculties so meek, hath been So clear in his great office, that his virtues Will plead like angels, trumpet-tongu'd against The deep damnation of his taking off; And pity, like a naked new-born babe, Striding the blast, or heaven's cherubin, hors'd U pan the sightless couriers of the air, Shall blow the horrid deed in every eye, That tears shall drown the wind.
- Full Text:
- Date Issued: 1988
Co-operative breeding in the Pied Starling
- Authors: Craig, Adrian J F K
- Date: 1987
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/447786 , vital:74674 , https://doi.org/10.1080/00306525.1987.9633905
- Description: Pairs of Pied Starlings Spreo bicolor build the nest, but only the female incubates. After the chicks hatch, subadult and juvenile birds help feed the young. Helpers also feed young after they leave the nest. In most cases parents contribute more than the helpers which may attend several different nests. Associations between members of the same breeding group may persist for up to three successive seasons.
- Full Text:
- Date Issued: 1987
- Authors: Craig, Adrian J F K
- Date: 1987
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/447786 , vital:74674 , https://doi.org/10.1080/00306525.1987.9633905
- Description: Pairs of Pied Starlings Spreo bicolor build the nest, but only the female incubates. After the chicks hatch, subadult and juvenile birds help feed the young. Helpers also feed young after they leave the nest. In most cases parents contribute more than the helpers which may attend several different nests. Associations between members of the same breeding group may persist for up to three successive seasons.
- Full Text:
- Date Issued: 1987
Breeding condition of male red bishops under artificial photoperiods
- Authors: Craig, Adrian J F K
- Date: 1985
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/447761 , vital:74672 , https://doi.org/10.1080/00306525.1985.9639572
- Description: Testis development, as indicated by bill colour changes, and moult were followed over two years in nine birds kept under constant conditions of 14 h light:10 h dark. All birds maintained at least partial nuptial dumage throughout this period, but most continued normal cycles of wing moult. The testes continued to show cycles of enlargement and regression.
- Full Text: false
- Date Issued: 1985
- Authors: Craig, Adrian J F K
- Date: 1985
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/447761 , vital:74672 , https://doi.org/10.1080/00306525.1985.9639572
- Description: Testis development, as indicated by bill colour changes, and moult were followed over two years in nine birds kept under constant conditions of 14 h light:10 h dark. All birds maintained at least partial nuptial dumage throughout this period, but most continued normal cycles of wing moult. The testes continued to show cycles of enlargement and regression.
- Full Text: false
- Date Issued: 1985
The distribution of the Pied Starling, and southern African biogeography
- Authors: Craig, Adrian J F K
- Date: 1985
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/447882 , vital:74681 , https://doi.org/10.1080/00306525.1985.9639580
- Description: The Pied Starling is restricted to South Africa, Lesotho and Swaziland, but within this region it occupies a variety of habitats. Its modern distribution is certainly influenced by its association with man. However, a comparison with other vertebrate species, and with patterns of plant distribution, suggests that its geographical distribution has been determined primarily by its evolutionary history. A hypothesis for the origin of this species leads to several predictions concerning biogeography in southern Africa.
- Full Text:
- Date Issued: 1985
- Authors: Craig, Adrian J F K
- Date: 1985
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/447882 , vital:74681 , https://doi.org/10.1080/00306525.1985.9639580
- Description: The Pied Starling is restricted to South Africa, Lesotho and Swaziland, but within this region it occupies a variety of habitats. Its modern distribution is certainly influenced by its association with man. However, a comparison with other vertebrate species, and with patterns of plant distribution, suggests that its geographical distribution has been determined primarily by its evolutionary history. A hypothesis for the origin of this species leads to several predictions concerning biogeography in southern Africa.
- Full Text:
- Date Issued: 1985
The winter diet of gentoo penguins at Marion Island
- LaCock, G D, Hecht, Thomas, Klages, N
- Authors: LaCock, G D , Hecht, Thomas , Klages, N
- Date: 1984
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/448453 , vital:74731 , https://doi.org/10.1080/00306525.1984.9634486
- Description: The diet of Gentoo Penguins Pygoscelis papua at Marion Island was studied during September 1982. Samples were obtained from 64 birds using a stomach-pump. Fish accounted for 70% of the diet by wet weight, and crustaceans 30%. Fishes occurred in 72% of the samples, crustaceans in 75%, cephalopods in 13%, and molluscs in 8%. Cephalopods and molluscs did not form a significant proportion of any single sample. Harpagifer georgianus was the predominant fish in the diet (92,7% of otoliths recovered), and Nauticaris marionis was the only crustacean.
- Full Text:
- Date Issued: 1984
- Authors: LaCock, G D , Hecht, Thomas , Klages, N
- Date: 1984
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/448453 , vital:74731 , https://doi.org/10.1080/00306525.1984.9634486
- Description: The diet of Gentoo Penguins Pygoscelis papua at Marion Island was studied during September 1982. Samples were obtained from 64 birds using a stomach-pump. Fish accounted for 70% of the diet by wet weight, and crustaceans 30%. Fishes occurred in 72% of the samples, crustaceans in 75%, cephalopods in 13%, and molluscs in 8%. Cephalopods and molluscs did not form a significant proportion of any single sample. Harpagifer georgianus was the predominant fish in the diet (92,7% of otoliths recovered), and Nauticaris marionis was the only crustacean.
- Full Text:
- Date Issued: 1984
Moult in southern African passerine birds: a review
- Authors: Craig, Adrian J F K
- Date: 1983
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/447813 , vital:74676 , https://doi.org/10.1080/00306525.1983.9634475
- Description: In the most recent checklist 398 passerine species are recorded for southern Africa. This paper lists information on the moult of 114 species, of which 27 are Palaearctic migrants, or birds for which there are data from European populations only. For 65 additional species data of uncertain relevance to southern African populations are included in appendices. There is much interspecific variation in both pattern and timing, even between members of the same family and genus. Aspects requiring special attention in future studies are discussed.
- Full Text:
- Date Issued: 1983
- Authors: Craig, Adrian J F K
- Date: 1983
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/447813 , vital:74676 , https://doi.org/10.1080/00306525.1983.9634475
- Description: In the most recent checklist 398 passerine species are recorded for southern Africa. This paper lists information on the moult of 114 species, of which 27 are Palaearctic migrants, or birds for which there are data from European populations only. For 65 additional species data of uncertain relevance to southern African populations are included in appendices. There is much interspecific variation in both pattern and timing, even between members of the same family and genus. Aspects requiring special attention in future studies are discussed.
- Full Text:
- Date Issued: 1983