Piper, W. H., and R. H. Wiley.   1990.   The relationship between social dominance, subcutaneous fat, and annual survival in wintering white-throated sparrows (Zonotrichia albicollis).   Behavioral Ecology and Sociobiology 26:   201-208.

SUMMARY

We used multivariate analysis to identify factors correlated with level of subcutaneous fat (a form of stored energy) in a migratory, wintering population of white-throated sparrows (Zonotrichia albicollis).

Dominant birds, residents from previous years, and birds residing in certain regions of the study area tended to have high mean fat levels during January and February. On the basis of differences

in levels of fat, dominant prior residents could probably survive 50% longer without food than subordinate newcomers.

An additional analysis revealed that dominant sparrows returned more frequently to the study area than subordinates, a result that might indicate higher survival.

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