Today is Sunday, and we shall therefore have a themed batch of bird photos from John Avise. His notes and IDs are indented, and you can enlarge the pictures by clicking on them.
I think that Skimmers (in the family Laridae) are the only birds in the world in which the lower mandible is appreciably longer than the upper mandible. And the birds use this peculiar culinary device in their unique hunting process for small fish. As their name hints, Skimmers fly low back-and-forth across a body of water, cutting its surface with their lower mandible until they hit a fish, whereupon the bill snaps upward to snatch the food. Furthermore, if the bird accidentally hits a hard submerged obstacle during this fishing process, the Skimmer’s fast reflexes quickly tilt the head downward and back so that the bill is not broken. This week’s photos show the strange anatomy and feeding behavior of the Black Skimmer (Rynchops niger), North America’s only native Skimmer.
Adult in flight:
Head portrait from the side: [JAC: notice how high the eyes are on the head, surely another adaptation for skim-feeding.]
Head-on view showing razor-thin bill:
Head-on view in flight:
Flock on land:
Flock, side view:
Adult showing junior how to skim:
Bird with his reflection:
Leaving a long cut in the water:
Accidentally startling a big fish:
Tucking head back to avoid an obstacle:
A successful catch: