Primary wing-moult and site fidelity in South African mousebirds (Coliidae)
- Craig, Adrian J F K, Bonnevie, Bo T, Hulley, Patrick E, Underhill, George D
- Authors: Craig, Adrian J F K , Bonnevie, Bo T , Hulley, Patrick E , Underhill, George D
- Date: 2014
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/449474 , vital:74824 , https://doi.org/10.2989/00306525.2014.931310
- Description: Based on large samples of birds mist-netted in the Eastern Cape and the Western Cape, moult of the primary remiges in both Speckled Mousebirds Colius striatus and Red-faced Mousebirds Urocolius indicus occurred throughout the year with no regional or seasonal patterns evident. The same picture emerged for the White-backed Mousebird Colius colius in the Western Cape. This aseasonality of wing-moult for all three species in South Africa was further supported by the full data set of moult records available in the Safring database. We were thus unable to use the Underhill–Zucchini model to estimate the moult parameters for these species, but an extended moult period seems likely. Recapture data for the Eastern Cape strongly suggest that Speckled Mousebirds are resident or revisit sites frequently, whereas this is not the case for Red-faced Mousebirds.
- Full Text:
- Date Issued: 2014
- Authors: Craig, Adrian J F K , Bonnevie, Bo T , Hulley, Patrick E , Underhill, George D
- Date: 2014
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/449474 , vital:74824 , https://doi.org/10.2989/00306525.2014.931310
- Description: Based on large samples of birds mist-netted in the Eastern Cape and the Western Cape, moult of the primary remiges in both Speckled Mousebirds Colius striatus and Red-faced Mousebirds Urocolius indicus occurred throughout the year with no regional or seasonal patterns evident. The same picture emerged for the White-backed Mousebird Colius colius in the Western Cape. This aseasonality of wing-moult for all three species in South Africa was further supported by the full data set of moult records available in the Safring database. We were thus unable to use the Underhill–Zucchini model to estimate the moult parameters for these species, but an extended moult period seems likely. Recapture data for the Eastern Cape strongly suggest that Speckled Mousebirds are resident or revisit sites frequently, whereas this is not the case for Red-faced Mousebirds.
- Full Text:
- Date Issued: 2014
Primary wing-moult in relation to body-mass, wing-length and latitude in four insectivorous passerines from southern Africa
- Bonnevie, Bo T, Craig, Adrian J F K
- Authors: Bonnevie, Bo T , Craig, Adrian J F K
- Date: 2014
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/465424 , vital:76609 , https://doi.org/10.1071/MU13072
- Description: In southern African passerine birds, the timing of moult often varies regionally in relation to breeding season and patterns of rainfall, and may also differ between sexes in sexually dimorphic species. However, the relationship between feeding ecology andmoult has not been studied in this region. We investigated primary-moult, body-mass and wing-length in four southern African passerines belonging to a feeding guild of hawking (sallying) insectivores, using bird-banding (ringing) data. The timing of wing-moult, from December to April throughout the region, was very similar in all four species, in contrast to other sympatric species, which moult at different times in summer-and winter-rainfall regions. For each species the duration of moult decreased southwards, as did wing-length corrected for body-mass. There was no difference between the sexes in the timing or duration of wing-moult, even in sexually dimorphic species, but juveniles generally started moult later than adults and completed their moult more rapidly. Our results suggest that foraging ecology and life-history traits of insectivorous hawkers may constrain the timing of moult.
- Full Text:
- Date Issued: 2014
- Authors: Bonnevie, Bo T , Craig, Adrian J F K
- Date: 2014
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/465424 , vital:76609 , https://doi.org/10.1071/MU13072
- Description: In southern African passerine birds, the timing of moult often varies regionally in relation to breeding season and patterns of rainfall, and may also differ between sexes in sexually dimorphic species. However, the relationship between feeding ecology andmoult has not been studied in this region. We investigated primary-moult, body-mass and wing-length in four southern African passerines belonging to a feeding guild of hawking (sallying) insectivores, using bird-banding (ringing) data. The timing of wing-moult, from December to April throughout the region, was very similar in all four species, in contrast to other sympatric species, which moult at different times in summer-and winter-rainfall regions. For each species the duration of moult decreased southwards, as did wing-length corrected for body-mass. There was no difference between the sexes in the timing or duration of wing-moult, even in sexually dimorphic species, but juveniles generally started moult later than adults and completed their moult more rapidly. Our results suggest that foraging ecology and life-history traits of insectivorous hawkers may constrain the timing of moult.
- Full Text:
- Date Issued: 2014
Variations in moult, morphology, movement and survival rates of the Sombre Greenbul Andropadus importunus within southern Africa
- Authors: Bonnevie, Bo T
- Date: 2014
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/448368 , vital:74725 , https://doi.org/10.2989/00306525.2014.902403
- Description: Ringing data from the South African bird ringing unit, SAFRING, were analysed to explore variations and trends in population parameters of the Sombre Greenbul Andropadus importunus in southern Africa. Adult and juvenile body mass increased southwards, whereas the relative sizes of wings and bills decreased southwards. Recapture and recovery data indicated that adults have very high site fidelity and suggested that juvenile dispersal is limited. The annual survival rate of adults was on average more than twice that of juveniles and there was little regional variation within either age group. The onset of primary wing moult became progressively later northwards, but the duration of moult did not vary significantly with latitude. Juveniles started their first normally descendent wing moult sequence about one month after adults.
- Full Text:
- Date Issued: 2014
- Authors: Bonnevie, Bo T
- Date: 2014
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/448368 , vital:74725 , https://doi.org/10.2989/00306525.2014.902403
- Description: Ringing data from the South African bird ringing unit, SAFRING, were analysed to explore variations and trends in population parameters of the Sombre Greenbul Andropadus importunus in southern Africa. Adult and juvenile body mass increased southwards, whereas the relative sizes of wings and bills decreased southwards. Recapture and recovery data indicated that adults have very high site fidelity and suggested that juvenile dispersal is limited. The annual survival rate of adults was on average more than twice that of juveniles and there was little regional variation within either age group. The onset of primary wing moult became progressively later northwards, but the duration of moult did not vary significantly with latitude. Juveniles started their first normally descendent wing moult sequence about one month after adults.
- Full Text:
- Date Issued: 2014
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