Meeting Abstract

46.3  Jan. 6  A comparative study of migratory behavior in white-crowned sparrows (Zonotrichia leucophrys) COVERDILL, A.J.*; CLARK, A.D.; RAMENOFSKY, M.; University of Washington; University of Washington; University of Washington alexac@u.washington.edu

Expression of migratory restlessness (MR) in captive birds has been considered a characteristic of migratory species. Paradoxically however, a few resident species also express MR. To address this issue, we describe migratory behavior to include the quiescent phase (QP), a transitional state between daytime activity and nocturnal flight, and specific behaviors that define nocturnal MR such as beak-up and beak-up flight, as identified in Gambel�s white-crowned sparrow (Zonotrichia leucophrys gambelii). Analysis of migratory behavior may further our understanding of nocturnal activity in captive birds and reflect migratory strategy. Thus, we compared three related species, which represent a spectrum of migration from long-distance flight to residence, under spring photoperiods. The long-distance migrant, Z.l.gambelii, expressed QP for a mean duration of 75min prior to dark phase. All individuals showed MR consistently with high frequency throughout the night. The short-distance migrant, pugetensis, expressed QP for a mean of 60min immediately following onset of night. MR was observed in 66% of individuals with variable frequency. In nuttalli, the resident race, QP was absent. The latter birds were nocturnally active at low intensity and only 33% expressed actual MR. Migratory fattening was apparent only in the migratory species. These results support observations that resident congeners of migratory species show nocturnal activity but this activity may not represent expression of migration but a predilection for nocturnal movement within confines of a territory. In light of these data, application of a more specific definition of migratory behavior may prove to be the most revealing in evaluating the spectrum of migratory strategies among the pacific races of white-crown sparrows.