Determining the temporal and spatial patterns of migration and the
degree of population segregation during migration is critical to
understanding
the ecology and evolution of migration as well as long-term
population trends of migrant birds. Whether breeding populations
differ in migration routes or times could suggest different source
of selection and require alternative management approaches. To
better understand migration patterns, we have incorporated two
distinct techniques to determine where, when, and how birds are
returning to breeding grounds.
Radio Tracking (Protocol) – Over the last several years we have been attempting to isolate migration corridors by radio tracking select birds on their way back to their breeding grounds. During the day, we capture birds and fix a small radio on their back. We then attempt to follow each individual through the night as it moves from one stopover location to the next. By following the specific path individuals are using as they return to breeding grounds, we hope to better understand the evolution of migratory behaviors and identify important migration corridors.
Stable
Isotopes (protocol) – In addition to looking at individual
migration behaviors, we are also attempting to understand broad
patterns across populations. Recent studies have shown that stable
hydrogen isotopes are a powerful research tool for identifying
where individuals procure resources to allocate to molt. Hydrogen
isotopes differ across latitudes, and by looking at the isotopes
in an individual’s feathers, we can identify the location where
that individual was when it produced that feather. By choosing
species that molt on their breeding grounds we are able to
identify the breeding locations of returning migrants (Paxton et
al. 2006).
the ecology and evolution of migration as well as long-term
population trends of migrant birds. Whether breeding populations
differ in migration routes or times could suggest different source
of selection and require alternative management approaches. To
better understand migration patterns, we have incorporated two
distinct techniques to determine where, when, and how birds are
returning to breeding grounds. Radio Tracking (Protocol) – Over the last several years we have been attempting to isolate migration corridors by radio tracking select birds on their way back to their breeding grounds. During the day, we capture birds and fix a small radio on their back. We then attempt to follow each individual through the night as it moves from one stopover location to the next. By following the specific path individuals are using as they return to breeding grounds, we hope to better understand the evolution of migratory behaviors and identify important migration corridors.
Stable
Isotopes (protocol) – In addition to looking at individual
migration behaviors, we are also attempting to understand broad
patterns across populations. Recent studies have shown that stable
hydrogen isotopes are a powerful research tool for identifying
where individuals procure resources to allocate to molt. Hydrogen
isotopes differ across latitudes, and by looking at the isotopes
in an individual’s feathers, we can identify the location where
that individual was when it produced that feather. By choosing
species that molt on their breeding grounds we are able to
identify the breeding locations of returning migrants (Paxton et
al. 2006).
