The birds now nesting, hanging out, or just passing through the marsh carry beaks ideally suited to their ways of life.
Many have a sort of “Goldilocks” facial protuberance – not too long, not too short, strong enough, but not so big as to be unwieldy.
The Red-Wing Blackbirds (female above, male below) eat a varied diet – small insects pried from the fleshy stalks of aquatic plants, small seeds, even larger grains from farm fields or bird-feeders – and their strong but slender beaks are great for this range of foraging.
The Grackle also grabs many meals in the marsh, and as many as possible from bird-feeders. They readily eat animals as large as grasshoppers, frogs, even mice – and their larger beak has a specialized hard keel that can crack acorns.
The reclusive but talkative Sora gathers its food from floating vegetation in the interior of reedy areas – Smartweed seeds, snails, dragonflies and other insects on the marsh surface.
The Turkey Vulture looks for larger fare, spotting dead animals while it soars over meadow, marsh or beach. Its unusually keen nose sniffs out “freshly dead” food even in thickets or under a forest canopy. Its beak can tear through the scales and skin of fish, the fur of rabbits, and the bones of other birds.
This time of year the Double-Breasted Cormorant spends a lot of time catching fresh fish in the marsh. With its heavy body the cormorant launches into flight awkwardly – but it dives with ease, propelling itself underwater with huge webbed feet, and its long beak is great for grabbing the squirming fish that make up nearly its entire diet.
Canada Geese also get a lot of their food underwater – but they eat vegetation, not fish, and in shallow water only so they don’t need to dive. Their medium-size beaks, AKA bills, are ideally suited to a vegetarian diet that includes grasses and seeds as large as corn or wheat.
A visitor with an exceptionally large bill dropped by last week. The Northern Shoveler’s bill is lined with scores of fine projections that form a sieve, allowing it to swim with its open mouth in the water catching tiny aquatic animals as well as seeds.
The shovel-filter is a clever adaptation – but the Greater Yellowlegs takes a different tack. This slender shorebird wades in shallow waters in the northern boreal forests. Its long, skinny, pointy and lightweight beak is just right for probing mudflats for aquatic insects, or occasionally grabbing a small frog or a minnow.
The Swallow species really go for beak minimalism. These superb flyers seem never to stop moving, swooping down low over the marsh surface or circling over the tops of trees. As they fly they are gobbling tiny winged insects one after another. A big beak would be pointless extra weight.
Composite photo at top: The Right Beak (click here for larger view). Clockwise from top left: Greater Yellowlegs, Turkey Vulture, Northern Shoveler, Sora.