The Stutchbury lab does research on the conservation biology, ecology, and behaviour of songbirds in North America and the New World tropics. Examples are given below with links to some recent publication.

Tracking Songbird Migration

The Stutchbury lab has used light level “geolocators” on purple martins and wood thrush  to track individuals to their wintering grounds and back. Geolocators are a critical new conservation tool that allows us to study the wintering region, and hence potential threats like tropical deforestation, where a given migratory population over-winters. These small devices have a stalk with a light sensor at the end, and are mounted on the back. When the bird returns in spring the geolocators are retrieved and downloaded; we determine sunrise and sunset times each day and thus estimate latitude and longitude. Spring migration rate was remarkably rapid with purple martins returning from Brazil in as little as 13 days, and most wood thrush returning from Honduras/Nicaragua in 13-15 days. We have recently repeat-tracked Wood Thrushes  in multiple years, and deployed geolocators across the range of Purple Martins to map migratory connectivity.

Stutchbury et al. 2009.pdf

Stutchbury et al. 2010 thrush migration.pdf

Stanley et al 2012 Repeat Tracking.pdf

Fraser et al. 2012 Purple Martin Migratory Connectivity.pdf

Fledgling Survival and Conservation

Another key conservation concern is the survival of juvenile birds during the first weeks and months after they leave the nest. After nestlings fledge from a nest they need several weeks of parental care and protection before they are truly independent and can prepare for migration. To measure mortality during this mobile fledgling stage requires radio-telemetry. Our studies on Hooded Warblers in Pennsylvania found that over 50% of nestlings who successfully leave the nest nevertheless are killed by predators before they are independent. We have also studied fledgling and juvenile survival in Rose-breasted Grosbeaks, Eastern Loggerhead Shrikes, and Purple Martins

Rush and Stutchbury 2008

Moore et al. 2010

Imlay et al. 2010

Extra-pair Mating Systems

The Stutchbury lab studies the extra-pair mating system of songbirds, where males and females routinely seek copulations outside the otherwise monogamous pair bond. We often use radiotelemetry to document where and when males and females make secretive trips to visit neighbours. Recent work has shown that male Wood Thrush thwart extra-pair matings by following their females closely, even off-territory. Female Hooded Warblers sneak off-territory too, and prefer to visit and mate with neighbour males who sing a lot. Currently, postdoc Scott Tarof and grad students Pat Kramer & Cassandra Silverio are studying how extra-pair paternity and reproductive success in Purple Martins is related to parasite loads and offspring fitness.

Evans et al 2008

Chiver et al. 2008
 

Behavioural Ecology and Conservation of Tropical Birds

Tropical birds have a fundamentally different ecology from migratory birds and are at great risk from habitat destruction. Surprisingly little is known about the evolution of territory defense, mate choice, and mating systems in tropical birds. Ph.D. student Ioana Chiver is studying Red-throated Ant Tanagers in Panama using isotopes, hormone analyses and paternity anlayses to test how timing of breeding is affected by habitat quality and social behaviour.

Lance Woolaver, a PhD student, studied the conservation ecology and genetics of the Ridgway’s Hawk which is endemic to the island of Hispanola. This species is the most endangered hawk in the Caribbean with only 30-40 pairs remaining. Lance worked in the Dominican Republic banding parents to estimate the current population size and finding nests to measure productivity of breeding pairs. He also conducted genetic analyses to determine if the very small population size has resulted in unusually low genetic variation within the population.

Stutchbury and Morton 2008

Fedy and Stutchbury 2006
Gill et al. 2005