Western Grebes are extremely vulnerable to winter oil spills in California. They migrate from breeding colonies on inland lakes in western North America to wintering areas along the coast—where there are few opportunities to benefit these birds with restoration efforts. Many restoration opportunities exist at breeding sites, but our ability to encourage grebes' recovery after spills is still limited: we do not know which populations migrate to which regions.
PRBO biologist Diana Humple is working with her graduate advisor, Dr. Derek Girman of Sonoma State University, on a project that would increase our knowledge of where coastally wintering Western Grebes breed. Using genetic markers, and analyzing blood, feather or tissue samples of individuals throughout their range, they are determining genetic similarities between wintering and breeding populations. The aim is to find migratory "connectivity" for grebes, so that post-spill resources can be focused in appropriate regions. The same techniques can also be used to benefit other migratory species affected by oil spills.