isepiptesis

I thought that was odd, too. But apparently the man who coined this term (Alexander von Middendorff) did so in the context of a bird migration study, so that probably explains it. You probably also know that the same man coined the term radula in a mollusk study. :-)

On a related note, "migratory eels" has a nice ring to it.

Thought you'd like it, reesetee. Seems strange that the definition is restricted to birds though. Today's newspaper (Philadelphia Inquirer) had a map showing when monarch butterflies reach various areas as they migrate to their wintering grounds in Mexico. And what about migratory wildebeest and eels? Or phenology more broadly?

Nifty, mollusque! I'd forgotten all about this one. Consider it pilfered.

A line on a map connecting localities reached on one date by members of a species of migratory birds.