Bald eagle's breath lit up by sunlight at Hawk Conservancy Trust
FAQs about the photo:
Is this a completely wild bird?
No, it is a captive bird at the Hawk Conservancy Trust, UK [link]
How did you catch the breath?
It was a cool but sunny day. Combined with the dark background, the sunlight was enough to light up any mist to make it show up. The background was their shelter in the shade, but looks dark to the camera compared to the bird.
If you're in the area, I would definitely recommend visiting the Hawk Conservancy Trust where you can not only get a similar photo yourself, but they also run some spectacular flying displays.