Snowbird ancestors?

I notice Ancestry has updated the database Border Crossings: From Mexico to U.S., 1895-1957 which now has 5.4 million records. Some will be Canadians, maybe your snowbird ancestors.
You can search for southward migrating snowbirds in Ancestry's databases Border Crossings: From Canada to U.S., 1895-1954 and Border Crossings: From U.S. to Canada, 1908-1935 for the return.