Here’s some info I found, Hannes, on their first lap to cross the Gulf of Mexico when coming this way.

I’ve only seen the Ruby-throated hummers here.

Ruby-throats do not travel in flocks during hummingbird migration. Instead, each bird follows its own instincts on appropriate departure times and routes.

Scientists believe that each hummingbird begins its migration in response to environmental triggers. One trigger is the changing level and angle of sunlight. Another trigger is believed to be a drop in available natural food. As these signals continue to activate, the hummingbird makes its preparations and eventually departs.

On their northward trip, most have reached Mexico’s Yucatan Peninsula by February. In this lush jungle, they begin to feast on insects as they prepare for one of the toughest migrations for any bird. Each year, thousands of Ruby-throated Hummingbirds fly over the open water of the Gulf of Mexico rather than follow the longer shoreline route. These brave little birds will fly non-stop up to 500 miles to reach U.S. shores. It takes approximately 18-22 hours to complete this amazing solitary flight.

Some hummingbirds aren’t strong enough, though, as many oil riggers and fishing boat crews can attest. Every year, exhausted Ruby-throated Hummingbirds take temporary refuge on offshore oil rigs and boats floating in the middle of the Gulf of Mexico. These birds rest a while before bravely launching back into their flight across the open water.

When they return south, Ruby-throated Hummingbirds will follow the same daring migration route in reverse. They’ll charge up their energy reserves in the southern U.S. and then zip across the gulf toward their winter home. That’s two big, non-stop trips each year for Ruby-throats – you have to admire their tenacity!
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