Diurnal pattern of mass in an urban Marlborough population of silvereyes (Zosterops lateralis) | Notornis and Birds New Zealand

[摘要] Silvereyes (Zosterops lateralis) in an urban population in Marlborough, New Zealand showed considerable diurnal changes in body mass. At first light, average mass was 12.39 g, rising to 13.91 g by dusk. This represented a 12% average loss of mass overnight. The overall average mass was 13.22 g; birds were 6% below average at 0700 h, but increased rapidly to be near the average for most of the day, rising significantly in the 2 hours before dusk (1700 h). This pattern of diurnal mass change is consistent with theoretical models suggesting that birds should manipulate daily mass gain in order to trade-off starvation risk with mass-dependent predation risk.

[学科分类] 动物科学

[关键词] Diurnal weight change;mass-dependent starvation risk;silvereye;Zosterops lateralis