Double-brooding in Southern Yellow-billed Hornbills Tockus leucomelas. (8th June 2021)
- Record Type:
- Journal Article
- Title:
- Double-brooding in Southern Yellow-billed Hornbills Tockus leucomelas. (8th June 2021)
- Main Title:
- Double-brooding in Southern Yellow-billed Hornbills Tockus leucomelas
- Authors:
- Stanback, Mark
Millican, David
Versfeld, William
Nghikembua, Matti
Marker, Laurie
Mendelsohn, John - Abstract:
- Abstract : Double-brooding is an avian breeding strategy where birds produce at least two successful nests in a single season. Double-brooding is seen most frequently in small passerines for which the breeding season is lengthy enough that they can easily fit in multiple nesting attempts. Such a pattern of breeding is therefore less common among large birds with long incubation periods and slow offspring development. In the case of hornbills (Family Bucerotidae), double-brooding would be unexpected for not only these reasons, but also due to the fact that the females of nearly all hornbill species exhibit a synchronous moult of flight feathers immediately following clutch completion. Double-brooding would thus require not only an exceptionally long breeding season, but also that females undergo two very costly flight feather moults in a single season. Here we describe the double-brooding of 10 individual female Southern Yellow-billed Hornbills Tockus leucomelas in a single Namibian population during the 2019/2020 breeding season. Because the breeding cycle of Yellow-billed Hornbills lasts three months, double-brooding requires that conditions remain appropriate for breeding for more than half the year, a stringent requirement in a relatively arid country. Our analysis demonstrates that double-brooding is not a response to either small spring brood sizes or the disappearance of fledglings and appears not to be limited to females of above-average mass. Rather, we found thatAbstract : Double-brooding is an avian breeding strategy where birds produce at least two successful nests in a single season. Double-brooding is seen most frequently in small passerines for which the breeding season is lengthy enough that they can easily fit in multiple nesting attempts. Such a pattern of breeding is therefore less common among large birds with long incubation periods and slow offspring development. In the case of hornbills (Family Bucerotidae), double-brooding would be unexpected for not only these reasons, but also due to the fact that the females of nearly all hornbill species exhibit a synchronous moult of flight feathers immediately following clutch completion. Double-brooding would thus require not only an exceptionally long breeding season, but also that females undergo two very costly flight feather moults in a single season. Here we describe the double-brooding of 10 individual female Southern Yellow-billed Hornbills Tockus leucomelas in a single Namibian population during the 2019/2020 breeding season. Because the breeding cycle of Yellow-billed Hornbills lasts three months, double-brooding requires that conditions remain appropriate for breeding for more than half the year, a stringent requirement in a relatively arid country. Our analysis demonstrates that double-brooding is not a response to either small spring brood sizes or the disappearance of fledglings and appears not to be limited to females of above-average mass. Rather, we found that double-brooding is most common among females who initiated their spring nest early and appears to be associated with wetter-than-average years. … (more)
- Is Part Of:
- Ostrich. Volume 92:Number 2(2021)
- Journal:
- Ostrich
- Issue:
- Volume 92:Number 2(2021)
- Issue Display:
- Volume 92, Issue 2 (2021)
- Year:
- 2021
- Volume:
- 92
- Issue:
- 2
- Issue Sort Value:
- 2021-0092-0002-0000
- Page Start:
- 105
- Page End:
- 112
- Publication Date:
- 2021-06-08
- Subjects:
- breeding cycle -- molt -- Namibia -- two nests -- wet season
Birds -- Periodicals
Birds -- South Africa -- Periodicals
598.05 - Journal URLs:
- http://www.ingentaselect.com/rpsv/cw/nisc/00306525/contp1.htm ↗
http://www.tandfonline.com/toc/tost20/current ↗
http://www.tandfonline.com/ ↗ - DOI:
- 10.2989/00306525.2021.1891479 ↗
- Languages:
- English
- ISSNs:
- 0030-6525
- Deposit Type:
- Legaldeposit
- View Content:
- Available online (eLD content is only available in our Reading Rooms) ↗
- Physical Locations:
- British Library DSC - 6313.000000
British Library DSC - BLDSS-3PM
British Library HMNTS - ELD Digital store - Ingest File:
- 16843.xml