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The 2017 hurricane season sure packed a wallop. Three major storms -- Harvey, Irma, and Maria -- decimated the Caribbean and the southern US.

While the focus has rightfully been on the impacts to those living in the storm’s path, you might wonder how other creatures fared. Some species seem to be able to sense the impending danger and flee. Landlubbers like us that don’t get out of the way just have to hunker down as best they can.

But birds and other airborne animals sometimes do what sounds like the worst idea ever: they ride things out in the eye of the storm. Meteorologists have witnessed this thanks to something called dual-polarization or dual-pol radar, which uses pulses of electromagnetic waves to detect the size and shape of objects in two dimensions. Based on the pattern of the waves, they can see the proportions of whatever’s in the storm — including birds and insects, which stand out because they’re much less spherical than, say, a raindrop.

And when meteorologists map out what they’ve detected with radar, they often find a bunch of animals inside the eyes of big storms. Heading into a hurricane for safety sounds pretty bold … and ill-advised. But within the eye, the weather is calm.

It’s a spot of extremely low pressure, which helps drive the overall storm, but isn’t very windy itself. It doesn’t even have clouds, since the air in the eye is about 5 degrees warmer than the rest of the storm, and it can hold more water before condensing. So, all things considered, it’s relatively safe for birds and bugs.

Not that it’s an intentional strategy on their part—they probably don’t plan this out. Either the eye forms around them, or they just happen to find the eye and then end up kinda stuck there. This especially happens with seabirds.

The real danger is running into the eyewall, the vertical wall of clouds that surrounds the eye, which is the most intense part of the storm. It has the heaviest rainfall and strongest winds. Sticking to the eye can work, but it can be tough to make it through if a hurricane is especially long-lived.

Trapped birds don’t have much choice but to keep flapping—they can’t really stop to sleep or eat—so this kind of travel can wear them out. Sometimes they die. And since, you know, a hurricane swept through their habitat, there may not be much left to come home to.

Or, if they’re migratory birds, they can be blown hundreds of kilometers off course. In 2005, Hurricane Wilma deposited a flock of North American chimney swifts in Western Europe. More than 700 of the birds died, and ornithologists found that the following year, the total population had been cut in half.

It can be hard to collect good data on what happens to birds during and after a storm, as each hurricane is different. But birdwatchers can help with that. Safety first, obviously, but if you ever see “hurricane birds”—species well outside of their usual homes during or after a storm—you can report your observations so scientists can learn more about how animals deal with tropical cyclones.

It’s one of the more unusual types of citizen science. Thanks for asking, and thanks as always to all our patrons on Patreon. Your support helps us weather any storm.

If you want to help us make more episodes like this, you can go to patreon.com/scishow. [ ♪ Outro ♪ ].