Reproductive ecology of White-throated Sparrows
About the Project
Since 2005, Dr. Scott Ramsay has been conducting research in Algonquin Park focusing on the causes and consequences of variation among female white-throated sparrows (Zonotrichia albicollis) in the timing of nest initiation, and the number and size of eggs laid.
Factors that may influence these variables are spring temperature and precipitation, and patchlevel habitat differences such as the amount of food available leading up to egg-laying and the food availability for nestlings when they hit their peak demand. Females may also base some of their decisions on the characteristics of their partners, including the prospects male provisioning effort, which in whitethroats is related to morph.
Some interesting patterns are starting to emerge from the data, including a strong influence of clutch initiation date on the likelihood of a nest surviving to fledging. I am also interested in various aspects of the songs of male white-throats including their utility as an indicator of male identity in the absence of banding information for estimating year-over-year survival rates. Finally, I am also using stable isotope analysis of feathers grown prior to spring migration to estimate where the white-throats that breed in Algonquin Park spend the winter. The data so far suggest that males winter farther north than females, tan-striped individuals winter farther north than white-striped individuals, and many of the birds in our population never leave Ontario in the winter.