This American Pipit lives up in the Burrowing Owl Sanctuary. This morning after a thorough preening (See “Pipit Preening,” Dec. 4 2021) it ventured outside the artistic fence, across the paved pathway, and into the Nature Area to hunt for its breakfast. It paced for some minutes through the grass, its eyes busy checking in all directions. Then its diligence paid off. It spotted a hefty caterpillar, longer than its beak. No problem. After a bit of arranging the prey to pinch it by the head, the bird opened its throat wide and slid the furry sausage down its hatch in a wink. The frames from the video, below, show details. The bird gives a delicate appearance, as if the only prey its slender, tweezer-like beak could handle were little gnats and midges. It’ll take those, too, but clearly this bird can handle bigger fry.
Birds don’t have teeth, so chewing the prey before swallowing is not an option. Some raptors tear their larger prey to pieces before swallowing, but most birds do exactly like this Pipit: swallow it whole, and let its stomachs sort it out. In birds, the first stomach is the gizzard, a muscular organ that crunches the food and squeezes out the good parts for the second stomach to digest. The indigestible parts, such as bug legs, wings, fur, etc., remain in the gizzard and later get regurgitated, either as a nicely shaped pellet (as with owls) or as a mess.