How to Identify Birds Are you amazed at how quickly birders can identify birds? Actually, it's just like getting to know your human neighbours. When you move into a new neighborhood everyone is a stranger, but soon you learn to tell people apart as you unconsciously catalog their characteristics. Their habits, shape, styles of walking, and "habitats" become familiar enough that you can recognize each neighbour immediately, even at a distance. Paying attention to individual differences can help you identify birds, too. You can recognize many birds simply by noting their shapes, even if seen only in silhouette. Other useful characteristics are a bird's posture, size (easiest to judge if you use familiar birds as a size reference), flight pattern and/or head-on flight profile, and the kind of habitat in which the bird was seen. Start by learning to identify general groups of birds- warblers, flycatchers, hawks, owls, wrens- whose members all share certain similarities. As your observation skills improve, familiarize yourself with the field marks- colored or patterned areas on the bird's body, head, and wings- that help distinguish species. Identifying Bird Groups by Silhouette Birds vary in size. Silhouette alone gives many clues to a bird's identity, allowing birders to assign a bird to the correct group or even the exact species. In this illustration are 23 different birds. How many can you recognize just by their silhouettes? Look carefully - don't miss the ones hiding in the leafy tree! Pay attention to the following: body shape proportions of the head, legs, wings, tail shape and length of the bill Silhouette Descriptions Cardinal Medium-sized finch-like songbird with long tail Strongly conical, seed-eating bill Crested head Crow Large size Stout body, medium-length tail Heavy, strong bill Dabbling Duck Typical duck shape, with heavy body Short tail, held above water's surface Horizontally flattened bill Dove Plump body, with short legs and neck Small head Pointed wings Slight swelling at base of upper bill Finch Small to medium size Conical, seed-eating bill Notched tail Silhouette Descriptions Grackle Slender body, long tail Strong, slightly curved bill Jay Mid-sized crow-relative with long tail Some have crest on head Kestrel Small bird of prey Typical streamlined falcon shape, with long pointed wings and long tail Short raptorial (sharply hooked) bill, feet with sharp talons Kingbird Medium-sized perching bird with relatively large head Broadly-flattened, typical flycatcher bill Kingfisher Large head, often with shaggy crest Very short legs and tail Long, strong, pointed bill Silhouette Descriptions Meadowlark Chunky body, short tail Strong legs Straight, strong, pointed bill Mockingbird Long, slender body, long legs and tail Small, slender bill Nuthatch Small size, chunky body, short tail Straight, slightly upturned bill Strong legs and feet Clings to tree trunks, usually head downwards Plover Small to medium-sized shorebird Relatively large head, short neck Short, rather thick bill, sometimes slightly swollen at tip Ground dwelling Quail Chunky, rounded body, with short tail Small head, very short neck Ground dwelling Silhouette Descriptions Screech-Owl Small nocturnal bird of prey Chunky body, large head Feathered tufts on head resemble ears Upright stance Shrike Medium-sized predatory songbird Relatively large head Perches horizontally Bill with strong hook at tip Starling Chunky body, short tail Strong legs and feet Straight bill Swallow Small size Very slender body, short legs, and long, pointed wings Small bill with wide gape Silhouette Descriptions Vireo Small, tree-dwelling bird Small, cylindrical bill (slight hook at tip, visible only at close range) Perches horizontally, often leans forward while foraging Warbler Very small, tree-dwelling bird Perches horizontally Slender insect-eating bill Woodpecker Clings to tree trunks, head upwards Uses tail as prop as it hitches its way up tree trunks Strong but short legs and strong feet Straight, strong bill for excavating wood Wren Very small size Compact body, with relatively long legs Thin, slightly curved bill Holds tail upright Skulking habit Using Field Marks to Identify Birds In order to describe a bird, ornithologists divide its body into topographical regions: beak (or bill), head, back, wings, tail, and legs. To help with identification, many of these regions are divided still further. This next diagram of regions of the bird's body shows some of the commonly used descriptive terms. Birds display a huge variety of patterns and colors, which they have evolved in part to recognize other members of their own species. Birders can use these features - known as field marks to help distinguish species. Pay particular attention to the field marks of the head and the field marks of the wing. Bird Topography Field Marks of the Head When identifying an unknown bird, the following field marks of the head are particularly important: Eyebrow stripe (or superciliary line, above the eye) Eyeline (line through the eye) Crown stripe (stripe in the midline of the head) Eyering (ring of color around eye) Throat patch Color of the lore (area between base of beak and eye) Whisker mark (also called mustache or malar stripe) Color of upper and lower beak Presence or absence of crest Beak shape and size are also important identifying characteristics. Field Marks of the Wing In a few groups, notably warblers and vireos, the presence of wing markings gives positive identification even if the bird is in non-breeding plumage. In other groups, such as flycatchers and sparrows, the absence of any wing markings may be an important distinguishing characteristic. Note the presence or absence of the following: Wing bars Wing patches Molt and Confusion! Molt is the process of which old feathers are replaced by new. Molt Pattern Natal Down (plumage) Prejuvenal Molt Juvenal Plumage Prebasic Molt Basic Plumage Prealternate Molt Alternate Plumage Prebasic Molt Basic Plumage et cetera… Feather Wear (form of molt) Feathers are worn not replaced to reveal fresh appearance. Identifying Bird Groups by Posture Striking a Pose Posture clues can help place a bird in its correct group. Watch an American Robin, a common member of the thrush family, strut across a yard. Notice how it takes several steps, then adopts an alert, upright stance with its breast held forward. Other thrushes have similar postures, as do larks and shorebirds. Posture Vertical Posture Certain bird groups have distinctive vertical posture when perched on a branch. Flycatchers, hawks, and owls typically sit in an upright pose with tails pointing straight down. Posture Horizontal Posture Other birds perch horizontally on vegetation with tails pointing out at an angle, for instance vireos, shrikes, crows and warblers. Similar? Distinguishing Similar Birds Distant perched crows and hawks may look alike, but paying attention to their different postures may help to tell them apart. The Red-tailed Hawk perches upright, whereas the similarly-sized American Crow perches horizontally. Using Familiar Birds as Size Reference Once you have assigned a bird to its correct group, size can be a clue to its actual species. Be aware, though, that size can be difficult to determine in the field, especially under poor lighting conditions or at a distance. Size comparisons are most useful when the unknown bird is seen side-by-side with a familiar species. In the absence of that, you can use the sizes of well-known birds, such as the House Sparrow, American Robin, and American Crow, as references when trying to identify an unfamiliar bird. Size Reference Woodpeckers: A crow-sized woodpecker would be a Pileated, but one the size of a sparrow might be a Downy Woodpecker (or a Ladderbacked Woodpecker in the Southwest). Size Reference Confusing Coloration: A yellow-andblack finch smaller than a sparrow is probably an American Goldfinch. Evening Grosbeaks have similar colors and patterns, but are almost robinsized. Size Reference In-between Sizes: Sometimes you need two reference birds for comparison. A Cedar Waxwing is bigger than a sparrow but smaller than a robin. A Blue Jay is larger than a robin but smaller than a crow. Using Flight Patterns as Identification Clues Most birds fly in a straight line, flapping in a constant rhythm, but certain bird groups have characteristic flight patterns that can help identify them. Birds of prey may be identified by the characteristic way they hold their wings when viewed flying toward you. Here are some useful identification tips: Flight Patterns Up-and-down Flight Pattern Finches exhibit a steep, roller-coaster flight, whereas woodpeckers generally fly in a pattern of moderate rises and falls. Flight Patterns Flapping Versus Gliding Flying accipiters such as Sharp-shinned Hawks, Cooper's Hawks, and Northern Goshawks typically make several wing flaps followed by a glide. Buteos, such as the Red-tailed Hawk, are usually seen soaring. Dashed lines indicate flapping, solid lines soaring. Flight Patterns Crow Versus Raven Flight patterns can sometime distinguish similar species. The American Crow, for instance, flies with deliberate, flapping wingbeats. The similar Common Raven often alternates flapping with hawk-like soaring. Head-on Flight Profiles Head-on flight profiles may also give identity clues. Soaring Turkey Vultures may look like hawks, but they hold their wings in a shallow V-shape, whereas most hawks and eagles hold their wings out flat. Black Vultures also have a flatter, more hawk-like profile. Northern Harriers hold their wings in more of a V-shape, but their slow, flapping flight near the ground generally gives away their identity. Notice how the Bald Eagle's profile is even more flat than that of a typical hawk, such as the Red-tailed Hawk. Using Habitat Clues to Aid Identification In general, each species of bird occurs only within certain types of habitat. And each plant community whether abandoned field, mixed deciduous/coniferous forest, desert, or freshwater marsh, for instance contains its own predictable assortment of birds. Learn which birds to expect in each habitat. You may be able to identify an unfamiliar bird by eliminating from consideration species that usually live in other habitats. (Be aware, though, that during spring and fall migration birds often settle down when they get tired and hungry, regardless of habitat.) Habitat Clues Abandoned Field Agricultural fields no longer used for farming form an "old field" habitat as they slowly revert to forest. In the Northeast and the Mid-Atlantic states, the original grasses are replaced with plants such as goldenrod, mullein, asters, and brambles (blackberry). Thickets of woody shrubs - such as honeysuckle and multiflora rose - develop, mixed with small trees such as red cedar, black locust and hawthorn. Birds found there include Field Sparrow, House Wren, Red-tailed Hawk, and Blue-winged Warbler. Habitat Clues Mixed Deciduous / Coniferous Forest In a broad band stretching from the Great Lakes region eastward to New England and the Maritime Provinces of Canada, the southern deciduous woodlands and the coniferous forests of the north meet and intermingle. There broad-leafed trees such as oaks, hickories, beeches, and maples mix with conifers such as spruces, firs, and hemlocks. Birds that live there include Winter Wren, Northern Goshawk, White-throated Sparrow, and Black-throated Green Warbler. Habitat Clues Sonoran Desert The Sonoran Desert is a hot, dry region covering 120,000 square miles in southwestern Arizona and southeastern California, as well as most of Baja California and the western half of the state of Sonora, Mexico. Tall saguaro cactus and spiny cholla cactus are common, mixed with trees such as ironwoods and palo verdes, and shrubs such as saltbush, creosote bush, and mesquite. Black-throated Sparrow, Cactus Wren, Harris's Hawk, and Lucy's Warbler can be found there. Habitat Clues Freshwater Marsh A freshwater marsh is a treeless wetland whose shallow water supports dense stands of mostly emergent plants (rooted in mud but with most of their foliage above water). Marshes are found throughout North America, often forming when ponds and shallow lakes fill in, although beavers may also play an important role in their formation. Typical vegetation includes cattails, bulrushes, sedges and reeds. In deeper pools submerged and floating aquatic plants occur, including water lilies, pondweed, arrowhead, duckweed, smartweed, bladderwort, pickerel-weed, water-shield, and sweet flag. Bands of shrubs such as alder and willow occur at drier marsh edges. Swamp Sparrow, Northern Harrier, Marsh Wren, and Common Yellowthroat are typical residents. Bird Song Only a few species of birds have no voice--storks, pelicans, and some vultures. Most birds produce some sort of vocal sound. The Passeriformes (perching birds,songbirds) are noted for their singing ability. Many birds are restricted to vocal sounds rather than songs or calls. Call- a brief sound of simple acoustic structure- a peep, cheep, squawk, chatter, etc. Song - a relatively long, often melodious, series of notes usually associated with some aspect of courtship. The vocal organ of birds is composed of membranes located at the junction of the bronchi and called the syrinx. When a bird sings, air from the lungs is forced through the syrinx and air passing over the membranes causes a sound. Either one of the two membranes, or both, may be used in singing. Since two different sounds may be produced, the variation in both loudness and frequency is enormous. The songbirds have the greatest number of muscles in the syrinx (4-9 pairs) while most other bird groups have only one pair. In general, the complexity of the syringial muscles is related to the complexity of the songs a bird can produce. But there are exceptions such as the American Crow, which has seven pairs of syringial muscles but a limited voice. Parrots on the other hand, can mimic the human voice and only have three pairs of syringial muscles. Evolution of Song Birds evolved from voiceless reptiles. What is the evolutionary advantage of song for it to have developed to the extent it has? Alarm notes to frighten predators. Finding each other in dense vegetation. As mobility increased with flight, the need for long-distance communication did also. As a way of keeping a group together- for protection and during migration. Non-vocal Sounds Passerines have the most well-developed songs and calls, but other birds with less vocal abilities have developed other sounds. Kiwis stamp their feed when annoyed. Boat-billed Herons, Storks, and Albatrosses rattle or clap their bills. Woodpeckers drum. The Ruffed Grouse drums with its wings. The nighthawk and hummingbirds often make sounds with their wings or tails. A number of birds make whistling sounds as they fly through the air- may or may not serve a purpose. Function of Song Bird songs are basically related to reproductive activities in one way or another. Calls may be related to reproductive or self-maintenance activities. Some specific functions of song: Proclaim sex/induce another bird to reveal its sex. There is a correlation between the complexity of the song and dull plumage and little or no sexual dimorphism. The duller the plumage and/or the more the sexes look alike, the more complex the song (e.g. Song Sparrows). Attract a mate. True for many species. Establish a territory. Often, males arrive on the breeding grounds before the females (e.g. Red-winged and Yellow-headed Blackbirds); singing establishes the territory and maintains it later. Stimulate and synchronize courtship behavior. Indicates readiness to breed by both sexes. Maintain pair bond. A female Song Sparrow will come off the nest and sing back to her mate. Signal changes in domestic duties. May trade feeding or incubation duties, signaled by song. Identify individual to young. Most precocial birds can recognize their own young - waterfowl and penguins, e.g. Experiments with Mallards indicate that communication between the female and young begins before hatching. "Species" identification. A song or call may be given to identify a bird of the same species or population. Hold flock together. Calls, usually, but often songs, are used to coordinate the movement of a flock; e.g. Pygmy Nuthatch, Mountain Chickadee. Intimidate enemies. May be use to scare predators. To perfect song through practice. Often, complex songs are learned through imitation and practice. Song Basically a bird’s song is a very specific type of communication. If a predatory bird is perched conspicuously in a tree small birds will often make themselves known by a behavior called mobbing; they set up a chorus of calls around the predator to point it out and perhaps chase it away. But if the predator is flying overhead, the small birds race to the nearest bush or tree and utter their calls from there. Many birds have warning calls that are species-specific. Crows give a warning call that will frighten away only other crows - this call has been recorded and used to scare other crows from cornfields. Starlings roost in trees in cities and can be pests; they can also be driven away by speciesspecific calls Robins and Grackles in the same flock are not affected. But in other cases, such as that of the Herring Gull, their alarm call will also scare away the Great Blackbacked and the Laughing Gulls. Parent birds can call to their young to make them ‘freeze’ in the presence of a predator, swim, peck at food, etc. Young birds can vocalize in such a way as to stimulate a parent to feed them, etc. Song is typically the function of the male, but there are many exceptions. The female Mockingbird, Cardinal, and Black-headed Grosbeaks have songs as complex as the males’. In the phalaropes, where sexual dimorphism and courtship roles are reversed, the female only sings. And if females hold individual territories in the winter, they may sing then even though they don’t sing during the breeding season. Song Variation and Song Ecology Each bird species exhibits a more or less characteristic song, but the song varies by age, sex, geographic location, and time of year. Populations of the same species of birds having different songs are song races; each variation in a song is a dialect. The white-crowned Sparrow is well-known for having many song races and dialects. Geographic variation in song is very common. But within different populations of the same species, the song is more stereotyped (less variable) when there are other species present with similar songs. But when no other species with similar songs are present, there is more variation in the song within a population of one species. More variation is not only allowed, but it helps the recognition of single individuals. Ecology of Song Males of many bird species use a singing post to call their mate or establish territory from - tree. post, wire, etc. Other birds the live in grasslands like the Horned Lark or Bobolink have a flight song. Birds living in dense vegetation such as in rainforests or thick reed beds have loud voices since vegetation absorbs sound as well as obstructs vision. So birds have evolved calls and songs at least partly in response to the structure of the habitat in which the call is given. Weather also has an influence on bird song. Both cool and hot weather decrease the amount of singing, as do rain and wind. A few species such as the Red-eyed Vireo sing more or less all day. But most birds sing more vigorously in the early morning and evening when there is less light. Some species sing at night, such as the Mockingbird and Nightingale. The amount of light rather than the time of day determines the beginning and end of singing. Cloudiness in the morning, for instance, will delay singing. Different bird species react to different amounts of sunlight. So some species in a particular area will begin to sing before others chime in (Dawn Chorus). The dawn chorus may begin at different times each day, depending on the amount of light, but the bird species will begin singing in the same order. Most birds show a seasonal variation in some that is mainly correlated with breeding activities and hormone production. The richest, fullest song generally comes in the spring when birds are establishing territories and courting (unmated males sing more). After egg-laying commences, the birds sing less so as not to attract predators. If a male bird renests or its mate is killed, it resumes full singing. In the fall after the breeding season, the bird stops unless it holds a winter territory. Inheritance and Learning of Song Generally, calls are genetic while songs are partly inherited and partly learned. Many studies have been done of song development; the classic one is the one done in England on the Chaffinch. The full song of the male Chaffinch performs the function of keeping other males from its territory and attracting females. This song is described as: ‘chip-chip-chip, tell-tell-tell, cherry-erry-erry, tissy-chee-wee-oo’ So what’s happening? In the wild, young Chaffinches learn some details of song from their parents or from other adults in the first few weeks of life. At this stage a young bird absorbs the general pattern of the song. But not until the critical learning period the following spring does the bird develop the fine details of the song. This is the time the young wild Chaffinch first sings in competition with other Chaffinches (for females, territory) and it learns the details of the song from its more mature neighbors. This, of course, leads to a bit of individual variation in song, although the general pattern is characteristic of the species. So song is an integration of both genetic and learned components and calls are entirely genetic. Song Mimicry A large number of birds exhibit varying degrees of vocal mimicry and imitate call notes of songs of other species. The Starling frequently mimics the Killdeer or nighthawk. Scrub and Blue Jays can imitate a Red-tailed Hawk. The Mockingbird (and others in the family- Catbird, Brown Thrasher) are well known for imitating other bird’s calls. But there is no evidence to indicate that these calls are an attempt to communicate with the other species. They may, in fact, only be a human interpretation as birds hear songs much differently that we do. A Bullfinch in England was taught to whistle the English National Anthem. A lyrebird in Australia learned to whistle the noon whistle at a factory. Parrots, mynahs, crows, and magpies apparently only mimic in captivity. And their imitation of a human voice is very different acoustically than the real human voice. Learning Birdsong If you are like me, your birdsong identification skills often need a few repairs after the long winter. Synapses dissolve, things come unwired - who knows what goes on up there, but a tune-up is definitely in order. Others of you may be venturing into the world of birdsong for the first time. You're sick and tired of that birding buddy who identifies every peep in the bush before you've even raised your binoculars. This is the year you get your revenge. Learning Birdsong To use bird vocalizations effectively as a means of identification (and that's what this is all about) you need some basic methods of representing the songs and calls. One familiar means is phonetics. This method employs sound units to mimic the vocalizations themselves. The words "chickadee" and "bobwhite" remind us of the sound the bird actually makes. Although many phonetic representations can be found in field guides, you will improve your birdsong ID skills by making up your own phonetics. Learning Birdsong Another good way to represent birdsong is with written descriptions. Again, there are many examples in field guides. Here too, certain descriptions will work for you to help you recall the song and the songster - others will fall flat. Don't settle for a description that's not right for your ears - make your own. Mnemonic (a pattern of letters or words formulated as an aid to memory) Yellow Warbler “sweet sweet sweet, I'm so sweet” American Robin “Cheerily, cheer-up, cheerily “ Olive -sided Flycatcher “Quick, three beers” Barred Owl “Who cooks for you, who cooks for you'all” Learning Birdsong A third method for learning and recalling birdsong involves diagrams or drawings. Depending on your learning style this may or may not work for you. Try making a drawing of the vocalizations that you hear. Learning Birdsong Now that you've had an opportunity to try all three methods of representing birdsong you should think a bit about your own personal learning style. To most effectively learn birdsong you will probably want to combine the methods that work best for you. Seeing Bird Song Two people attempting to describe a Green-tailed Towhee song verbally may conjure two entirely different sound images. Both would agree that it includes some whistle-like phrases, some trills and some buzzes. But such a description is most unsatisfying to anyone who has never heard the song. It is equally unsatisfactory for the ornithologist wishing to examine questions of individual repertoire size and variation, the amount of song and syllable sharing among individuals, the existence of dialects, or the degree of geographic variation in songs among populations. With the development of the sound spectograph or sonagraph, it became possible to objectively and quantitatively approach these questions, and the sonagraph has been used in an impressive number of studies over the past 25 years. This work has been facilitated by the development of high-quality portable tape recorders used in conjunction with microphones mounted in parabolic reflectors or with very sensitive directional microphones. The sonagraph produces on paper a graphic picture (a sonagram) of sound showing frequency (measured in kilohertz—thousands of cycles per second) on the vertical axis and time (in seconds) on the horizontal axis. Thus displayed, complex songs can be objectively separated into their constituent components, as shown in the sonagram (below) of a Green-tailed Towhee song. The song consists of an introductory note-complex followed by a buzzy trill, another note-complex, a trill composed of separable, repeated syllables, a single note, and ends with a buzzy trill of essentially continuous syllables. Seeing Bird Song Foraging Behavior as I.D Clues Conclusion Learning takes time Learn basics first Learn from experience Learn “in the field” Listen to songs Have fun Join bird watching club Hooooo am I?
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