Fish hawk. No, it's not some sort of bizarre hybrid organism from an obscure horror movie, with the head of a fish, and the body, wings, and talons of a hawk. But, then again, maybe it should be... ! But, no... Last week we scanned the actual fish hawk, also called an osprey, or more appropriately still, Pandion haliaetus. This is, without exaggeration, one of the coolest birds that will be in my sample, so this might be a slightly longer than average post. Osprey are large-ish birds, weighing between 1.4 and 2 kilograms (source), but their wings are especially large, with wingspans up to 180 cm (70 inches)! Their wings are so long that, even with the generous software trial that Nextengine, Inc. have been kind enough to give me, expanding the size of the objects that I can scan, I still have to scan both the upper and lower surfaces in sections. That means 4 scans per wing, instead of the usual two. It's slow going, but it'll be worth it in the end.
Photo credit: NASA via Wikipedia Commons.
Osprey are pretty much obligate piscivores, meaning that their diet is almost exclusively fish. That, in turn, means that they have to catch fish, and they do so in a particularly flamboyant manner. They soar quietly above the water, watching carefully for their quarry. When they spot a fish, the hover briefly above the target, rotate over into a dive, and plummet headfirst toward the water. Just before impact, they project their feet, adorned by impressively-long talons forward, in front of their heads, and tuck their long wings sharply backward.
Watching this makes you glad you're not a fish! Then, if they're successful in their hunt, the emerge from the water, meal in hand (or foot... whatever, semantics.) Carrying a fish through the air, though, can create a tremendous amount of drag, if you don't orient it correctly. Fortunately for our osprey, they have especially flexible ankles that allow them to rotate the fish from being perpendicular to their body to parallel, creating a nice streamlined shape, and allowing the bird to minimize its effort to get dinner on the table.
Photo credit: Simon Carrasco via Wikimedia Commons.