Abstract
The Alpine swift (Apus melba) forages on insects caught exclusively on the wing, implying that dependent nestlings face acute food shortage in periods of cold and rainy weather. Therefore, there should be strong selection on nestling swifts to evolve physiological strategies to cope with periods of undernutrition. We have investigated intra-individual changes in nestling pectoral muscle and body temperature in response to a 1-week period of inclement weather. The pectoral muscle is the largest reserves of proteins, and nestlings have to devote a large amount of energy in the maintenance of body temperature. The results show that nestling pectoral muscle size and body temperature were significantly reduced during the episode of inclement weather. Assuming that these physiological changes are adaptive, our study suggests that nestling swifts spare energy by a pronounced reduction (up to 18 degrees C) in body temperature and use proteins from the pectoral muscle as a source of extra energy to survive prolonged periods of fasting.
| Original language | English |
|---|---|
| Pages (from-to) | 387-393 |
| Number of pages | 7 |
| Journal | Journal of Ornithology |
| Volume | 148 |
| Issue number | 4 |
| Early online date | 19 Jun 2007 |
| DOIs | |
| Publication status | Published - Oct 2007 |
Bibliographical note
We are grateful to Herbert Biebach for lending us the muscle meter, the late Theo Marbot for providing us access to the Swift colony in Bienne, the Swiss meteorological stations for providing us meteorological data, two anonymous referees for helpful comments on the manuscript and the Swiss Science Foundation for financial support (grant no. PP00A-109009 to PB and no. PP00A-102913 to AR).Keywords
- pectoral muscle
- starvation
- torpor
- weather condition
- food shortage
- organ size
- growth
- physiology
- protein
- chicks
- flight
- mass
