Copyright © 2001 DK Publishing, Inc
All rights reserved.
ISBN: 0-7894-7157-4
Contents
Introduction *.6
How this Book Works8
Guide to Visual References10
Anatomy of Birds12
Topography of a Bird14
Variations within Species.16
How to Identify Birds.18
Identifying Birds in Flight.20
Behavior22
Abundance and Distribution24
Watching Birds in the Backyard26
Watching Birds in the Field.28
How to Be a Better Birder.30
Conservation32
Extinction34
Species Profiles *38
Accidental Species.734
Glossary.736
Index740
Acknowledgments752
Chapter One
HOW THIS BOOK WORKS
Until now, no tool for identifying birds has also provided access to information on behavior, nesting, flight patterns, and similar birds in a compact and user-friendly format. Written for the novice as well as the experienced birder, this book showcases in individual page profiles each of the 696 species of birds documented for western North America. The species are in taxonomic order and include all those known to breed west of the 100th meridian in North America north of Mexico, or adjacent islands and seas within 200 miles of the coast, and all species documented as regular visitors or casual vagrants by the American Ornithologists' Union (AOU) and the American Birding Association (ABA). Only those species listed on the current AOU Check-list of North American Birds (7th edition, 1998 and its 42nd Supplement, 2000) and the ABA 1998-99 ABA Check-list Report, Birding 31:518-524 are included. Additionally listed are more than 80 rare species that have been recorded as accidental visitors to the western half of the continent. This list begins on page 734. Other species that have been seen but not yet accepted by the AOU or ABA are not included. Also excluded are a host of introduced exotic species that are living in the wild, mostly in southern California and southern Florida, that are not yet recognized by either the AOU or the ABA as having viable breeding populations in North America.
FINDING YOUR BIRD
To find a bird, you can scan the pages of the book, or look up either scientific name or common name in the index. The species are in taxonomic order, beginning with the nonpasserines such as grebes, loons, ducks, hawks, owls, doves, hummingbirds, and woodpeckers. They are followed by the passerines, the perching or songbirds, which begin on page 428. Once you have found your bird's species profile, it will help you identify the bird as well as provide ready reference to its natural history.
GUIDE TO VISUAL REFERENCES
PHOTOGRAPHS
Because users of this guide will be viewing these birds in backyards, woodlands, and other natural environments, realistic photographs are used as visual reference. Some rare and seldom-photographed species are illustrated. Unless otherwise noted, the primary image shows the male bird in breeding plumage. If the adult female has significantly different plumage from the male a second image depicts the female in breeding plumage. If field marks are not visible in a photograph they are described in the accompanying text.
ILLUSTRATIONS
Many birds also have other plumages, including the winter plumage, which are depicted in illustrations. The plumage of the immature if different from both adults also is illustrated. Some species have different color morphs, which are also illustrated.
SIMILAR BIRDS
In many cases it can be difficult to distinguish between certain birds in the field. Thus species accounts feature a list of similar birds with accompanying text that identifies distinct features and behavior that clearly set them apart. Male and female symbols indicate the sex of the bird that could be mistaken for the species being profiled.
DISTRIBUTION MAP
Each species profile has a map showing where the bird is likely to be seen either all year long (permanent resident), in the breeding season (summer resident), or in the winter (winter resident). The maps depict only those parts of each species' range within North America and up to approximately 100 miles offshore north of central Mexico to the northern borders of Canada.
SCALE SILHOUETTES
These show the silhouette of the bird overlaid proportionally on a copy of this book.
NEST IDENTIFICATION
The Nest Identification box provides icons describing nest shape and location.
FLIGHT PATTERN
Each bird's flight pattern is shown in its species profile by an icon. For more information on flight patterns, see page 20.
HABITAT
At the bottom of each species account is a set of icons representing all the habitat types in the order in which the bird is found, from the most to the least likely.
ANATOMY OF BIRDS
Birds are the most diverse terrestrial vertebrates with more than 9,800 extant species. Mammals are the only other homeothermic group with whom they share the planet. Yet, although mammal species number less than half that of birds, the mammals are much more varied in body shape and size. Mammals vary in form from primates to giraffes to armadillos, with specialists in running, hopping, flying, swimming, burrowing, digging, and climbing. Birds, however, all look like birds—with the same basic architecture, a body shape dictated by the demands of flight.
FEATHERS
Birds have three basic types of feathers: down, contour, and flight (wing and tail) feathers. Down feathers are next to the bird's skin for insulation. The contour is the most commonly recognized feather and the one that covers most of the bird's body. Typical contour feathers consist of a central shaft or quill and the flattened portion or vane. Contour feathers that extend beyond the wings and tail are the flight feathers.
BONES
In most species both the wings and the legs must be strong enough to transport the full weight of the bird, yet light enough to fly. Some bones have been fused and some bear internal struts. Ribs are overlapped for strength; others are hollowed, thinned, and reduced in numbers for lightness. In flying birds, and those flightless birds like penguins that use flipperlike forelimbs to "fly" underwater, the sternum, or breastbone, bears a thin knifelike keel to which the large flight muscles of the breast, the pectoral muscles, are attached
BILLS
Birds' bills are composed of a horny sheath overlying a bony core. The entire lightweight structure has evolved in countless ways to the specialized needs of its owner, from seed-cracking to nectar probing and from fish-catching to fruit-picking. Birds also use their bills to build nests, preen, and court. Bills may change in size and/or color in breeding season.
LEGS AND FEET
The legs of birds are thin, strong, and springy, and in most species lack feathers on their distal parts where they are instead covered with scales. Muscles, which are concentrated on the portion of the leg nearest the body, control the extremities with a series of tendons. Toes generally number four with three forward and one opposable toe pointed backward, but some North American birds have only three. Toes are covered by scales and have claws at their tips which in birds of prey are enlarged into strong talons.
WINGS AND TAILS
The shapes of wings and tails are an adaptation to where and how a bird flies. Look carefully at flight silhouettes; forest raptors (a) have rounded wings for living in dense vegetation; swallows (b) have narrow tapering wings. The tapering wings and narrow tail of a falcon (c) contrast with the broad splayed wings and broad tail of an eagle (d), which allow an eagle to soar. Terns (e) have long elegant wings; albatross wings(f) are very long, with an extended inner section for flying over water like a sailpane.
TOPOGRAPHY OF A BIRD
As you consult the species profiles in this book you will encounter a number of ornithological terms that describe the "landscape," or groups of feathers, of a bird's body. Learning these terms will help you use your field guide and, when you look at living birds, prompt you to see more detail with each sighting.
TIPS FOR THE FIELD
1. Start by looking at the bird's head. Note its bill and the markings on its face.
2. Get a feel for the bird's overall shape and size and note body markings.
3. Note shapes and markings of tail and wings.
4. Watch it fly and note markings visible in flight.
VARIATIONS WITHIN SPECIES
Birds are the most colorful of all terrestrial vertebrates. Their coloration varies widely not only from species to species but within species. Often plumage colors differ between the sexes, between adults and their young, and from season to season. All of these different color patterns increase the challenge of identification for the birder.
MALE/FEMALE
VARIATIONS
Within a species, adult
males often differ in color
and pattern of plumage,
and sometimes in size,
from adult females.
JUVENILE PLUMAGE
VARIATIONS
On an individual bird, color changes occur when feathers molt, or drop from their follicles to be replaced by new feathers. In its life span a bird will molt many times. After its first molt, when it loses its natal down, the bird will attain its juvenile plumage. This will be its first plumage with contour and flight feathers. This plumage often does not resemble that of either adult and is worn briefly for a few weeks or months. For the purposes of this book the term "juvenile" is used to refer to subadult plumaged birds that may, or may not, be sexually mature.
OTHER SUBADULT PLUMAGES
Although in many species, such as the bunting and cardinal, the juvenile attains adult plumage after its first year, there are species in which it takes the juvenile longer to do this. It may take juveniles of some species two years or more. These individuals may experience what are known as first, second, or even third winter or summer plumages before attaining the plumage of adult birds. The Ring-billed Gull is one such example.
SEASONAL VARIATIONS IN ADULT BIRDS
Most adult birds have two molts a year with a complete molt of all feathers after the breeding season and a partial molt in late winter/early spring in which only the head and body feathers are replaced.
The late winter or early spring molt produces the brighter plumage associated with many breeding birds and is called the breeding plumage or alternate plumage. Male ducks undergo a molt just after the nesting season begins and get a fresh coat of feathers that is drab like the female's called an eclipse plumage. Fall molts produce a plumage called winter plumage, fall plumage, or basic plumage.
OTHER VARIATIONS
Some genetic variations in color and pattern can be seen among populations representing different geographical races of a species. These races are also referred to as subspecies.
Hybrids between species may produce birds that share some characteristics of each parent but still have a very different appearance.
Some species have two or more color phases or morphs.
HOW TO IDENTIFY BIRDS
Birds that come to backyard feeders often stay long enough for you to study them in detail, but not all birds are so cooperative and often a fleeting glimpse is all you get. Learn to get the best look you can under the conditions and to see the entire bird well. First impressions of a bird, especially a new species for you, will give you clues for comparing it with birds you already know. What you are looking for are field marks, those physical clues that include size, shape, color patterns, and behavior, and also the habitat the bird is in and the sounds it may make.
Learn to routinely and quickly look at the details of the head; markings on the body, wings, and tail; and the shapes of the bird's parts.
SONG
Many expert birders rely on their ears as much as their eyes to identify birds. Any of the many cassette tapes, CDs, or videos can help you learn the songs, calls, and other sounds birds make
BEHAVIOR
The behavior of the bird will also provide clues to its identity. Does it bob, wag, or pump its tail either up and down or back and forth? Note its flight pattern. Does it back down a tree or go headfirst? For more information on Behavior, see page 22
IDENTIFYING BIRDS IN FLIGHT
How a bird flies—the speed of the wing stroke as well as the pattern—can often help you recognize a species.
Direct—steady flight with regular wing beats, along a constant line; typical of most species, including waterfowl, herons, doves, crows, shorebirds, and many songbirds.
Dynamic soaring—glides over water "downhill" with the wind to its back and when close to the surface quickly turns 180 degrees back into the wind. There the bird is lifted back up to near the original height upon which it turns back and soars "downhill" again. Characteristic of many pelagic species, including albatrosses, shearwaters, and petrels.
Flap and glide—alternates a burst of several wing beats with a short or long level glide. Many birds of prey, both hawks and owls, use this flight pattern as do Black Vultures, ibis, and pelicans.
Flightless—many species living in environments free of predators have given up the energy-demanding activity of flight. The only flightless North American species, the Great Auk, was hunted to extinction in 1844.
Glide—wings are held fully or partially extended as the bird loses altitude. Many birds glide down to a landing, or from perch to perch. Hawks may glide from the top of one thermal to the bottom of the next in migration.
Hawking—flying up from the ground or down from an aerial perch to seize a flying insect and looping back down to the same or nearby perch. Characteristic of flycatchers and other small, active insect-eating birds such as warblers, the Cedar Waxwing, and several species of woodpeckers.
Hovering—rapid wingbeats while the bird remains suspended in one spot over the ground or water. Typical of hummingbirds, kingfishers, American Kestrel, Osprey, Rough-legged Hawk and many small birds that hover briefly to glean food from vegetation.
Mothlike—an erratic, sometimes bouncy, slow flight seen in nightjars, a few storm-petrels, and in the display flights of some small birds.
Skims—the flight pattern of the Black Skimmer in which the bird flies a steady course with its lower mandible cleaving the surface of still water as it feeds.
Static soaring—requires about a twentieth of the energy of flapping flight. Birds soar on rising heated columns of air, thermals, or on deflected currents and updrafts. Large hawks, eagles, vultures, storks, White Pelicans, and gulls soar this way.
Straight line formation—an energy-saving style of flight used by some larger birds such as cormorants, pelicans, ibis, some waterfowl, and others. Birds may fly one behind the other, or abreast as do some scorers and eiders.
Undulating—some small birds conserve energy by rising on one or more wing beats and then folding the wings to the body and swooping down to the next wing beat. Characteristic of woodpeckers, finches, and chickadees.
V formation—an energy-saving flight style used by some larger birds, including ducks, geese, cranes, and cormorants.
Zigzag—a pattern used by birds flushed from the ground as a way to elude predators, The Common Snipe and several species of quail are good examples.
BEHAVIOR
A large portion of the bird behavior we admire is instinctive and associated with particular species and families. So as you look for field marks, notice the bird's body language. It will give you many dues to its identity.
TAIL MOVEMENT
Some birds flip their tails as they move or perch. The tail may be cocked at an angle over the back, fanned open or closed, wagged, bobbed, or pumped up or down. Some birds constantly bob their bodies up and down as they walk or stand; others bob or jerk occasionally, while others sway back and forth as they walk.
BODY MOVEMENT
Some birds hop like a sparrow. Some run or walk. They may climb trees straight up, hitch up or back down them, walk headfirst down them, or cling upside down. Many birds wade like herons and egrets, or swim like ducks and geese. Some aquatic species feed by dabbling or tipping up their bodies with their heads and necks beneath the surface. Others dive completely below the surface.
FORAGING
Notice whether the bird forages on the ground, in the treetops, or at the mid-story level. Shorebirds may stay on the dry sand or away from the water's edge on a mudflat, or they may wade in the shallows, while some species may wade up to their bellies. Some shorebirds pick at their food while others drill and probe rapidly in the mud.
DISPLAY BEHAVIORS
Many species exhibit distinctive display behaviors during breeding season. They may dance like Prairie-Chickens, cranes, or Western Grebes; skylark like sparrows or buntings; or put on the aerial shows of woodcock and snipe. Many species, especially groundnesters, will try to lead intruders away from the nest with distraction displays including the broken-wing or crippled-bird act.
ABUNDANCE AND DISTRIBUTION
What does it mean when someone says a bird is "common" or that a species is "abundant" or "rare?" To appreciate a bird species' presence (or lack of it) in a given region you need to consider the factors of habitat, geographical range, and season of the year. Keep in mind that the distribution and abundance of birds, among the most mobile of the earth's creatures, are not static and the boundaries of populations often change. Birds are easily impacted by changes in climate and habitat brought about by natural or human causes, with seasonal migrations being the most obvious result. Thus knowing the seasonal occurrence of a bird is important in confirming its identification. The range maps in this guide are color-coded to provide you with this information. You can get even more specific information from local checklists, local bird books, websites, and local birders.
WATCHING BIRDS IN THE BACKYARD
If you provide suitable food, shelter, and water, birds will come to your backyard. If you offer a variety of these necessities you will attract a greater diversity of birds. Place your feeders, nesting boxes, and birdbaths where the birds will feel safe from people and animals and where you can see the birds as you go about your daily routine.
FOOD AND FEEDERS
Many people enjoy feeding birds year-round. Basic types of feeders include platform feeders, hopper feeders, tube feeders, ball feeders, window feeders, fruit feeders, nectar feeders, and suet feeders. Standard foods include black (oil) sunflower seed (the best single seed), striped sunflower seed, hulled sunflower (chips/hearts) seed, niger (called "thistle") seed, safflower seed, white prose millet seed, red millet seed, milo seed, corn (whole kernel, shelled, and cracked), peanuts, peanut butter, suet and suet mixes, fruits, and nectar.
WATER
Birds need water as much as they need food. If you include even one dependable source of water in your yard you will attract a great variety of birds to drink, bathe, and cool off. If there is a running water or dripping water element even more species will come. There are many styles of water containers to choose from but the only requirement is: Maintain a stable supply of clean water in a shallow container no deeper than three inches.
SHELTER AND NEST BOXES
Planting trees, shrubs, and other vegetation not only provides food for birds but shelter and nesting places. Many species will use nest boxes. Others will use nesting shelves or ledges, and larger species will use raised nesting platforms. Nesting boxes can be made of wood, aluminum, or plastic; natural gourds are often used for martins and swallows.
