I am looking for information on the effect of geological/oceanographic factors on Pacific gray whale populations, especially how they were impacted by and responded to loss of access to arctic feeding grounds due to the Bering land bridge. For instance, did the Pacific population undergo repeated bottlenecks due to the loss of the feeding grounds, or were they able to manage on resources in the northern Pacific ocean? (Secondarily, I am interested in how the closing of the Central American seaway affected the subsequent evolution of Atlantic and Pacific gray whales.) I searched Google Scholar, Ebsco Host (which I have access to courtesy of my public library), Wikipedia, and did a general web search with Google, using search terms such as "eschrichtius biogeography" and "eschrichtius land bridge." So far, the only reference I have located is an article by Victor Scheffer in The Bering Land Bridge, edited by David M. Hopkins, which I have on order but have not yet seen. Can anyone suggest other relevant references? Thank you, Terry Morse 935 SW 10th St. #6 Newport, Oregon 97365 tmorse@teleport.com http://home.teleport.com/~tmorse/index.html * "The grand leap of the whale up the Fall of Niagara is esteemed, by all who have seen it, as one of the finest spectacles in nature." - - Benjamin Franklin, satiric 1765 letter to the editor of a London newspaper.