Susan Gruber

Look at the related stories sidebar for “Animated Occurrence Maps Show Birds’ Migration Across Entire U.S.” Google that phrase will also get you there. Just across 48 states, not the entire hemisphere — but another exciting representation of mass data. There are even migrating birds shown in NE Ohio.

Of course it’s ridiculous and not true, but I don’t think it says there is no spring migration in OH. Birds don’t migrate as a single mass, so that can’t be what the dot represents. The paper seems to be behind a paywall, but my guess is each dot represents a calculated “center of mass” for all reports of that sp. at each time increment. I see some spp. at times flicker in & out of existence, or jump around less smoothly — I’d suppose that represents no or few reports. IOW, NE Ohio just never happens to be the average location for all North American reports of any species. Way cool data display!

I’m amazed at how tough birds are considering how small and delicate they are compared to so many other vertebrate species. They survived the major mass extinction event of 65 mya. I have a feeling they’ll be here long after humans go extinct (by their own devices).