When to stay, when to go: trade-offs for southern African arid-zone birds in times of drought
South African Journal of Science
| Field | Value | |
| Title | When to stay, when to go: trade-offs for southern African arid-zone birds in times of drought | |
| Creator | Dean, W.R.J. Barnard, P. Anderson, M.D. | |
| Description | Arid environments remind one of the punctuated equilibriumtheory of evolution: they experience long periods of stasis and low productivity, interrupted with episodic rainfall which spurs reproduction and movement. Birds, as highly dispersive organisms, are among the most dramatic indicators of these fluctuations. Here we review birds’ two main strategies, residency and nomadism, and the trade-offs faced by individuals in uncertain times. In general, wet years stimulate higher densities of nests (i.e. smaller territories), larger clutch sizes, unseasonal breeding, and at some times of year, higher breeding success. Rainfall above a certain threshold triggers breeding in resident species and an influx of nomadic species which breed and then move on. The environmental cues which trigger nomadism are sometimes poorly understood, but include distant thunderstorms for aquatic species, and perhaps for insectivores. Environmental cues that draw nomadic granivores to areas that have had recent rain are not known. | |
| Publisher | AOSIS | |
| Date | 2009-12-11 | |
| Identifier | 10.4102/sajs.v105i1/2.7 | |
| Source | South African Journal of Science; Vol 105, No 1/2 (2009); 24 1996-7489 0038-2353 | |
| Language | eng | |
| Relation |
The following web links (URLs) may trigger a file download or direct you to an alternative webpage to gain access to a publication file format of the published article:
https://journals.sajs.aosis.co.za/index.php/sajs/article/view/7/7
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