Savannah Sparrow, Passerculus sandwichensis, reproductive success

Abstract

Savannah Sparrow (Passerculus sandwichensis) breeding phenology and reproductive success were studied at Isle Verte, Quebec, from 1976 to 1980. The span of nest initiation, clutch size, number of young fledged and causes of egg and nestling mortality are compared with similar data on five other populatons of the same species in different geographic areas. Multiple nesting tendencies vary among these populations and appear to be related more to reduced predation pressure than to latitude or geographic location.