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How do Birds Find Their Food?
For the meanings of bird parts which you do not understand in this Hub, see my bird glossary.
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The beaks of most birds are unique for eating a special type (or types) of food, but careful study and review shows that most birds eat a great selection of food. Competition between species is averted at various times of the day or night.
Probing Scarlet Ibis & Brewer's Blackbird
Brown Creeper going up tree trunk
Red-breasted Nuthatch (one of the N.A. species)
Probing: is a feeding behavior in which birds reach into tree bark, mud, or soil in search of insects, worms and other prey.
Shorebirds - such as sandpipers, dowitchers and Common Snipes - get the best part of their menu by probing into mud with their long beak for worms and tiny shellfish. Each type of shorebird has either a different length beak or a distinct style of poking around.
Three master probers are American Woodcocks, Common Snipes and dowitchers, but they each live in individual places and so they evade rivalry. A woodcocks commonplace is in overgrown, upland fields. The Common Snipe prevails in wet, swampy fields. Dowitchers occupy open mudflats. All dig their beaks deep into the soil and mud, and they can spread the flexible tip of their beak to gobble up grubs and other prey from beneath the ground.
Nuthatches, Brown Creepers, and Black-and-white Warblers probe cracks and crevices in tree bark. They avoid conflict by poking from various inclines and at distinctive sites on tree trunks and branches. You can probably see one or more of these three birds in your yard.
For instance there is the Brown Creeper - which of course is brown, and it is also streaked. It 'creeps' up the tree trunks and has a long stiff tail for support. It probes the bark for insects.
Then there are the nuthatches but there are more than one type so the colors vary. These birds forage for both seeds and insects on twigs plus small branches.
Also we have the Black-and-White Warbler. Besides being streaked in black and white, the male has a black throat and the female has a white one. It, too, creeps on tree trunks but instead of only going up - like the Brown Creeper does - the B&W Warbler is able to creep in any direction.
They all go their own ways so as not to disturb the others.
Example of hawking insects
Brown Honeyeater (Australia) hawking
Hawking: is a method of seizing flying insects.
Normally a bird sits at the top of a tall tree or on the stub of a dead branch. The bird flies out and nabs a flying bug, it then resumes its seat to wait for its next prey to come along. Cedar Waxwings, and flycatchers such as kingbirds and the Olive-sided Flycatcher, capture large insects such as dragonflies that fly within the birds' area.
Flycatchers have large flattened beaks with which they snatch and grip their prey. Receptive bristles on the borders of their beaks help them to judge when to open it. Plus a pointed hook on the tip allow them to keep a tight grasp on their meal.
I have two photos of birds from Australia using this method but they are not the only ones which do. There are many birds in the US and other countries which also use this.
Cattle Egret gleaning
Lewis's Woodpecker gleaning
Gleaning: is a type of insect-capturing action in which the bird plucks insects off of leaves, stems, tree trunks and other regions.
Most small insect eating birds - birds such as warblers, chickadees and titmice - glean while they remain perched. Of course, they have to hop around in order to get from leaf to leaf. Red-eyed Vireos and small flycatchers such as the Least, Acadian and the Willow Flycatchers search the vegetation.
Another form of gleaning is 'leaf-tossing'. We see the American Robin (and many other birds) do this so regularly that we get used to it. These birds are doing the same thing as the birds on the branches. The only difference is these birds are searching for insects beneath the leaves on the ground instead of up in the trees. Various birds do this in individual ways. Robins do it by pushing the leaves side-to-side with their beak; thrashers hop forward, grab a bunch of leaves, and then sort of hop/slide backwards - the list goes on.
Acorn Woodpecker on a Black Oak Tree.
Chiseling: is the normal eating manner of woodpeckers.
Did you take woodshop in school? Woodpeckers have their own wood shop. They are taught very young all about chiseling and soon become experts at it.
Their strong, sturdy beaks are well adjusted for whittling at wood. Most woodpeckers use their firm beak to open holes through the bark to obtain passage to tunneling insects. The woodpeckers only disturb the bark to get at the insects with their long tongues. Hairlike whiskers are as a screen protecting their nostrils from airborne dust and wood chips. They have "spongy bone" and thick muscles in their skull to avoid headaches and other injuries.
Like the shorebirds which have different length beaks for probing to varied depths into mud, woodpeckers also have several length beaks which allow entrance into the different levels where insects dwell in the bark and tree core. They also have a very long, coiled tongue. (The tongue generally goes towards the back of the head, towards the top of the head and back to the front. Then down and around most of the eyeball. It is wrapped in different ways in different woodies.)
Downy Woodpeckers have the shortest beaks and make the shallowest forced entrances. Their short beak permits them to dine on very small twigs and even weed stems which are too small for larger woodpeckers. In relation, the crow-sized Pileated Woodpecker can chisel many inches into trees and is able to toss wood shavings 3 inches long. Woodpeckers rely on their hearing to identify the gnawing noise of carpenter ants and wood-boring beetle larvae and the humming wings of overwintering cluster flies. They also rely on hearing since their eyes are closed to keep the eyes protected from wood dust.
Brown Thrasher looking for food
Leaf-tossing: is a common feeding behavior of ground-feeding birds such as the American Robin, towhees, thrashers and others.
Many of us, if not all, have seen the robin do this and wondered why.
By scratching at loose leaves these birds expose beetles, caterpillars, ants and other hidden insects. The robin and other thrushes - robins are in the thrush family - are birds which toss the leaves aside with their beaks. By the way, when the robin pauses and cocks its head it is not taking a break, it is watching for movements of the insects. It does this because the eyes are on the side of the head. Thrashers use the method of basically brushing the leaves out of the way. One of the methods - which I have seen - is that they hop forward, grab a bunch of leaves with their feet and pull the leaves backward. Then if the bug is in view they nab it with their beak before it hides again.
In a performance called foot-raking many species of herons, egrets, cranes and storks use their feet to stir up the muddy bottom in order to startle crayfish, tadpoles, small fish and other animals into the birds' striking range. Wood Storks agitate the bottom with their pink toes and then let their open beak sway back and forth through the muddy water to be aware of moving fish. Likewise, Snowy Egrets disturb the bottom with their bright yellow feet. Which may help to spook small fish into noticeable range. Foot-stomping is a similar foot action used on muddy soil by Herring Gulls and some cranes. The birds' stomping creates rapid waves that cause earthworms to come out on the surface where the grubs become easy prey.
Chimney Swift may be sweeping for insects
Sweeping: is a feeding style in which a fast-flying bird (such as a swallow, nighthawk, or swift) opens its beak, grabs its chase, and ingests it in mid-flight.
"Wait a minute. This sounds pretty much like hawking", you might say, "What is the difference?", you ask.
In hawking the birds have longer and thinner beaks, besides perching, searching for insects and diving. Then they return to the perch and start again.
In sweeping, the birds have very short and wider beaks plus very short legs and usually they are flying most if not all of the time.
These birds do not fly about simply helter skelter searching for food with their mouth wide open all of the time. All types of dirt would enter its mouth that way.
What they do is this: they locate their prey by vision, once they have it in their sites then they dive in and open their beak just in time to snatch up the flying insect. Birds which use this method to eat have very large mouths and unusually small beaks. Most also have a set of altered rictal whiskers (rictal bristles) that look more like eyelashes than feathers. These create a perceptive "insect net" around the mouth. As soon as an insect touches the "net", the bird instantly gulps the insect into its mouth and swallows it.
Diving birds: such as loons, grebes, puffins and certain ducks - have many uncommon variations.
The different birds dive to varied depths to avoid competing for different types of food.
One example of these variations is that the diving birds are heavier than the surface-swimming water birds of the same size. The diving birds have solid bones and more bulky bodies. Without this extra weight, diving birds would be too buoyant to dive to great depths. Some penguins even swallow stones, presumably as ballast to achieve extra weight and easier control under the water. Cylinder-shaped bodies enhance streamlining, and propeller-like legs positioned far to the rear help them in powerful dives. Some birds even unfold their wings and "fly" under water. Considerable amounts of fat and dense down feathers insulate them from frigid water.
Most birds have hollow bones to assist them in maneuvering easily (flying, swimming, etc.).
Some divers reach remarkable depths. Atlantic Puffins may dive to 200 feet. The Emperor Penguin, the largest diving bird, may dive to 875 feet. Most diving birds remain under for less than a minute, but the Emperor Penguin is able to stay under for 18 minutes.
Plunge-diving is another way of breaking through the water surface. Buoyant birds - such as kingfishers, Brown Pelicans, gannets and boobies - plunge into the sea from heights as great as 100 feet.
Peregrine Falcons chasing a pigeon
Stooping: is a high-speed aerial pursuit performed by certain hawks, especially large falcons.
The Peregrine Falcon is the most accomplished in this method. It can see small birds at least at 3,000 feet away as it hunts by flying over an open environment. Peregrines start their stoop by pumping their wings to build up speed, then pull their wings partway to their sides and plunge downward. Building up speeds of at least 175 mph (even recorded at 200 mph), they usually snatch small easy mark, such as finches, from the air with their long sharp talons. They knock out larger birds by punching them, using their feet like closed fists, then follow their larger prey to the land.
Dabbling: is a common feeding behavior for surface feeding ducks, geese, and swans.
Contrary to their diving duck relatives, dabbling ducks are very light in weight and eat in water that is not too deep most of the time where they essentially turn upside down; their legs kicking at the surface and their tail pointed straight up while they reach to the bottom of the marsh or pond edge. They are in search of immersed plants, small fish, young frogs/toads and others - such as insects, snails and worms - that hide in the mud. Because their feet are located toward the rear of their body, diving ducks must run across the water to take wing, while the dabbling ducks can leap directly into the air.
Geese sometimes dabble but usually peck at food on the land, feasting on plant sprouts, spilled grain and critters like earthworms and beetle larvae. In contrast, swans use their long necks to extend to the bottom of the pond in search of food that is typically out of the dabbling ducks' reach. In this way, both birds evade conflict over eating the same food.
Green Heron fishing
A few herons, on the rocks
Stalking birds walk slowly along the ground or wade through shallow water searching for their prey.
American Robins seem to be listening for their quarry, but in reality they are turning their head to get a better view as they watch for very slight movements which give away the whereabouts of the worms. Then with a sudden jab, the robins grab and pull the worm completely out of its hole.
Herons and plovers stalk for food in dwellings dissimilar to each other but feed in a similar way.
Herons walk slowly through the shallow water looking down for action of a fish or frog that is not paying attention, or the heron may stand and wait. In a related way, plovers keep an eye on beaches, just as the robins stalk the lawns, plovers are always observant for the slightest movement.
Remember how you would go to the park and feed the bread to the geese and ducks?
Well some birds sort of do this same thing, only in their world it is called stalking because it is actually a form of trapping prey. Green-backed Herons use this method.They have an original way of attracting their small fish to come within their striking range. When bread or equivalent bait is attainable, they occasionally drop a morsel on the surface of the water and wait until a fish comes to the bread. One heron was even seen to retrieve the bait when it floated away and also to drive off ducks which tried to eat it.
Piracy: occurs when one bird steals food from another.
Successful 'pirates' (birds) are usually larger than the other birds from which they are stealing the food. For example, Bald Eagles sometimes chase Ospreys and make them drop their quarry. If the raider is prosperous, it picks up the food (often catching it in midair) and either eats it or carries the food back to their own nest. Piracy is most common during the nesting season when food demands are in great quantity. Herring Gulls try to steal from puffins if they get the chance, but puffins race back to their nest with fish and usually make it to their destination without interference.
Frigatebirds were even named for their habit of seizing food on the wing. Like the infamous frigate ships, frigatebirds wait for an innocent victim to reappear at its nest bringing food to its family, then the frigatebird swoops in and takes the meal with remarkable grace. They can sometimes tell if another bird is toting food by tuning in to the sounds it makes!
Scavenging gull in England
Scavenging: is the consumption of dead animals.
Gulls, crows, ravens and vultures are the most common scavengers. They clean up animals which are put to their final rest along the highways plus those in the fields or along the beaches. Gulls usually eat at the seashore from tourists, besides their normal routes. Crows/ravens eat practically anything. You will see them on roadsides, grass and feeders, etc.
Likewise, Bald Eagles often feed on fish remains found along lakes and rivers -- especially in the winter when waterways are frozen and fishing for live food is difficult.
Most scavengers locate their prey by sharp eyesight, but Turkey Vultures are an exception. These birds can find food with their especially good sense of smell. They are so accustomed to locating their food by smell that they occasionally reject carrion unless it gives off an appropriate odor. In comparison, Black Vultures use their sharp sense of sight for locating their food. In this way, the two species find individual types of food and thus circumvent struggling over food. It seems that vultures have an exceptional safeguard against the toxins and microbes in their diet.
Have you seen any of those actions?
How many have you seen?
Author: Kevin - ©2013
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