Posted by Carlos Sanchez on January 01, 1970 at 00:00:00
Brian and Rangel aren't referring to irruptive population growth, as in a population boom-bust cycle. Robins, waxwings, and goldfinches move into peninsular Florida nearly annually in varying numbers. They do not migrate in the traditional sense along set migration routes like shorebirds, raptors, and warblers. Rather, their movements across the country are more closely related to population dynamics and food availability. All three species can sometimes move into southern Florida in spectacular numbers -- an 'irruption'. Currently, it's more of a modest flight. Since we are so far south, they often never manage to reach the southern tip of the state. That is why these classic North American species are such a treat to the South Florida birder. Hope this helps, Carlos