Why Do Birds Sunbathe?

A cormorant catches some rays .... but why? (Photo Kitty Terwolbeck/Flickr).

The cormorant stood on a rock in the river, its back turned away from me. I was watching from the shore near the library in Camden, Maine, as the sun beat down on us both. I felt the warm rays heat up my skin and knew that I should have put on a good dose of sunblock. But while I was looking for shade, the bird was embracing the sun. It spread its wings out to its sides, stretched them out until the feathers splayed apart like thick black fingers, and stood there basking in the sunlight.

I was entranced. Despite the summer heat, I stood there watching it. Was the cormorant really sunbathing? It sure seemed that way. For the next 20 minutes the bird barely moved. By that time I was starting to turn pink, and I knew it was time to get out of the sun. The bird, however, just stayed still like a dark statue in the middle of the river.

Although I had never seen this particular behavior before, it turns out that sunbathing is a fairly common activity for many bird species, cormorants among them. According to the British Trust for Ornithology, sunbathing serves a couple of important roles for birds. First, it helps to spread vital oils along the feathers. Second, the heat helps to drive out any parasites that may be feeding on the bird’s plumage. Dealing with both issues helps to ensure that the bird’s feathers are well-maintained both for insulation and flight. The second, meanwhile, gives the bird a quick meal as it gets a chance to eat the insects while it preens itself.

Not every bird that worships the sun does it in the same way. Unlike cormorants, which stand, many species stay closer to the ground. Pigeons tend to lie on their side with one wing raised. Some doves, on the other hand, sit on the ground and raise both of their wings. Others flatten themselves out on the ground, the same way humans do when we lie out to sunbathe. Another dove species, the peaceful dove, plops down and spreads out, leaving its beak hanging open. As Jill and Ian Brown wrote last year for BirdLife Australia, the effect can make a bird look ill or distressed, but it’s really just enjoying a few rays.

By the way, you don’t have to wait to stumble upon this behavior like I did. Bird expert Melissa Mayntz writes that you can make your yard more ideal for sunning birds by pruning vegetation away from sunny areas and providing a cool birdbath. You also want to make sure that cats can’t get at the sunning birds, since they are particularly vulnerable on the ground.

If you do come across a sunning bird, be quiet, give it the space it needs to maintain its health, and snap a few photos from a distance — or just watch and enjoy. I sure did.