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We are a globally renowned resource that provides assistance with English to students, teachers, professionals, and organizations across the world. Our goal is to assist clients in their development as writers - no matter their skill level.

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Purdue OWL® - Purdue OWL® - Purdue University

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We are a globally renowned resource that provides assistance with English to students, teachers, professionals, and organizations across the world. Our goal is to assist clients in their development as writers - no matter their skill level.

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We are a globally renowned resource that provides assistance with English to students, teachers, professionals, and organizations across the world. Our goal is to assist clients in their development as writers - no matter their skill level.

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Purdue OWL® - Purdue OWL® - Purdue University

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We are a globally renowned resource that provides assistance with English to students, teachers, professionals, and organizations across the world. Our goal is to assist clients in their development as writers - no matter their skill level.

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Writing Assignment for "A Guide to Bird Watching

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Writing Assignment for "A Guide to Bird Watching

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Read "A Guide to Bird Watching"

Select 3 bird characteristics (everyone must use songs as one of the three) that you think will be most useful for identification purposes.

For each characteristic, write a summary of that characteristic, and a brief explanation of why you find that characteristic most useful for identification.

Also include one characteristic you think would be LEAST useful

CHARACTERISTICS

Postures & Flight Patterns

Size

Habitat

Colors and Plumage Patterns

Body Features

Range & Abundance

Behaviors

Field Marks

Time of Year

Your final draft must be typed, 12-point Times New Roman font, normal margins, double-spaced.

Create a header with your name and class period number.

Create a footer with "Page X of Y" in the bottom right corner.

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"Birding" is "the art of description"

Practice seeing differences when observing birds!

~ look at specific parts of the bird rather than the whole bird at once.

~ watch the bird as long as possible (describe it aloud, draw/write notes, then look it up in the field guide)

~ notice topography of the bird (crown, eye stripe, undertail coverts, belly, breast, leading edge, tail shape, etc.)

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The combination of size and shape is one of the most powerful tools to identification. Though you may be drawn to watching birds because of their wonderful colors or fascinating behavior, when it comes to making identifications, size and shape are the first pieces of information you should examine.

With just a little practice and observation, you'll find that differences in size and shape will jump out at you. The first steps are to learn typical bird silhouettes, find reliable ways to gauge the size of a bird, and notice differences in telltale parts of a bird such as the bill, wings, and tail.

Soon, you'll know the difference between Red-winged Blackbirds and European Starlings while they're still in flight, and be able to identify a Red-tailed Hawk or Turkey Vulture without taking your eyes off the road.

Become familiar with silhouettes

Often you don't need to see any color at all to know what kind of bird you're looking at. Silhouettes quickly tell you a bird's size, proportions, and posture, and quickly rule out many groups of birds - even ones of nearly identical overall size. Practice the silhouettes in the carousel at right.

Silhouettes are so useful because they help with the first step in any identification: deciding what kind of bird you've got. Once that's done, you've narrowed down your choices to one small section of your field guide.

Beginning bird watchers often get sidetracked by a bird's bright colors, only to be frustrated when they search through their field guide. Finches, for example, can be red, yellow, blue, brown, or green - but they're always shaped like finches. Learn silhouettes, and you'll always be close to an ID.

Judge size against birds you know well

Size is trickier to judge than shape. You never know how far away a bird is or how big that nearby rock or tree limb really is. Throw in fluffed-up or hunkered-down birds and it's easy to get fooled. But with a few tricks, you can still use size as an ID key.

Compare your mystery bird to a bird you know well. It helps just to know that your bird is larger or smaller than a sparrow, a robin, or a crow, and it may help you choose between two similar species, such as Downy and Hairy woodpeckers or Sharp-shinned and Cooper's hawks.

Judge against birds in the same field of view

Your estimate of size gets much more accurate if you can compare one bird directly against another. When you find groups of different species, you can use the ones you recognize to sort out the ones you don't.

For instance, if you're looking at a gull you don't recognize, it's a start to notice that it's larger than a more familiar bird, such as a Ring-billed Gull, that's standing right next to it. For some groups of birds, including shorebirds, seabirds, and waterfowl, using a known bird as a ruler is a crucial identification technique.

Apply your size & shape skills to the parts of a bird

After you've taken note of a bird's overall size and shape, there's still plenty of room to hone your identification. Turn your attention to the size and shape of individual body parts. Here you'll find clues to how the bird lives its life: what it eats, how it flies, and where it lives.

Start with the bill - that all-purpose tool that functions as a bird's hands, pliers, knitting needles, knife-and-fork, and bullhorn. A flycatcher's broad, flat, bug-snatching bill looks very different from the thick, conical nut-smasher of a finch. Notice the slightly downcurved bills of the Northern Flickers in your backyard. That's an unusual shape for a woodpecker's bill, but perfect for a bird that digs into the ground after ants, as flickers often do.

Bills are an invaluable clue to identification - but tail shape and wing shape are important, too. Even subtle differences in head shape, neck length, and body shape can all yield useful insights if you study them carefully.

Noticing details like these can help you avoid classic identification mistakes. An Ovenbird is a common eastern warbler that has tricked many a bird watcher into thinking it's a thrush. The field marks are certainly thrush-like: warm brown above, strongly streaked below; even a crisp white eyering. But look at overall shape and size rather than field marks, and you'll see the body plan of a warbler: plump, compact body, short tail and wings, thin, pointed, insect-grabbing bill.

Measure the bird against itself

This is the most powerful way to use a bird's size for identification. It's hard to judge a lone bird's size, and an unusual posture can make shape hard to interpret. But you can always measure key body parts - wings, bill, tail, legs - against the bird itself.

Look for details like how long the bird's bill is relative to the head - a great way to tell apart Downy and Hairy woodpeckers as well as Greater and Lesser yellowlegs, but useful with other confusing species, too. Judging how big the head is compared to the rest of the body helps with separating Cooper's Hawks from Sharp-shinned Hawks in flight.

Get in the habit of using the bird itself as a ruler, and you'll be amazed at how much information you can glean from each view. Good places to start include noting how long the legs are; how long the neck is; how far the tail extends past the body; and how far the primary feathers of the wing end along the tail (or past the tail).

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The combination of size and shape is one of the most powerful tools to identification. Though you may be drawn to watching birds because of their wonderful colors or fascinating behavior, when it comes to making identifications, size and shape are the first pieces of information you should examine.

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Charlo, Montana

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Nesting near the tree top homes of Charlo, Montana's Great Horned Owl family, an osprey couple is building a new nest and a new family!

The pair landed in Charlo on April 12th, 2016 and quickly got to nest prep, bringing in sticks and picking up dirt from the freshly turned field next door. After a short courtship, they've begun to mate.

Their bonding will lead to upwards of 160 mating attempts through these next few weeks that will eventually produce a clutch of two to four eggs. The eggs will hatch after an incubation period of 35-42 days and both parents will feed themselves and their chicks a fish-only diet. During incubation and chick rearing, the eggs and chicks are under nearly-constant parental watch to keep them safe from predators. About fifty days after hatching, the young begin exercising their wings to take their first practice flights from the nest. In early September, the young will begin their solo journeys to winter in South America.

This Osprey Cam is brought to you by our partnership with Owl Research Institute.

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Osprey Nest Camera - live from Charlo Montana | Explore.org

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Nesting near the tree top homes of Charlo, Montana's Great Horned Owl family, an osprey couple is building a new nest and a new family! The pair landed in Charlo on April 12th, 2016 and quickly got to nest prep, bringing in sticks and picking up dirt from the freshly turned field next door.

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Missoula, Montana

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The Owl Nest Cam features Long-Eared Owls (abbreviated LEOW). LEOWs get their name from prominent "ear" tufts. As you will see from watching the owl nest cam, LEOW is a medium-sized owl that travels lightly on the wing and looks slimmer and more upright on the perch than the Great Horned Owl.

Found in grasslands and open forests throughout North America, Europe, and parts of Asia, Long-eared Owls have bright yellow-orange eyes and buffy orange facial disks, black bills, and white to buffy chest feathers with brown streaking and barring.

Equipped with acute hearing for night hunting Long-eared Owls are primarily nocturnal, spending their time on the wing in search of small mammals. Usually silent, Long-eared Owls can be occasionally heard giving a deep singular "whooooo," a haunting call that can be heard up to a kilometer away.

One of only a handful of owl species that roost communally during the winter, Long-eared Owls nest in groups of 2-20, although records exist of 100 or more. During the breeding season, pairs form and lay an average of 3-5 eggs. Born with white natal down, the baby owlets leave the nest about 21 days after hatching. View this and more on the live owl cam!

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Owl Nest Cam - Live video of baby Long-Eared owls | Explore.org

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The Owl Nest Cam features Long-Eared Owls (abbreviated LEOW). LEOWs get their name from prominent "ear" tufts. As you will see from watching the owl nest cam, LEOW is a medium-sized owl that travels lightly on the wing and looks slimmer and more upright on the perch than the Great Horned Owl.

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Charlo, Montana

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The live owl cam features a Great Horned Owl: A powerful and adaptable bird of prey that has the most extensive range, the widest prey base and the most variable nesting sites of any American owl. Its large yellow eyes, pronounced ear tufts, and white bib distinguish the Great Horned Owl from related species, especially once its unmistakable multi-tone hoot is heard.

Silently gliding from perch to perch, the Great Horned Owl hunts easily after dark. While perched and ready to pounce, the Great Horned Owl is robustly equipped with excellent eyesight, the ability to swivel its head more than 180 degrees, and an acute sense of hearing to locate its prey.

As observers of the live owl cam may witness, Great Horned Owls regularly consume small mammals and are also known to eat fish and even large prey such as other owls or raptorial birds.

How is an owl a successful predator?

An owl's physiology is different than most birds' as its eyes take up the majority of its face. With eyes taking up the mass of the surface, there is no room left for muscles. Therefore, in order for an owl to look around it must twist its neck or body. Owls are able to twist their necks around 270 degrees. With their large eyes, they are able to pick up the sight of very small rodents and insects scattered along the floor. Along with their large eyes, owls have ears that give them the amazing ability to hear a twig break from up to 75 feet away. Look for these distinguishing features while watching the Great Horned Owl cam.

Another reason that owls are so successful when hunting at night is due to the construct of their feathers. Most birds have feathers with sharp edges effectively producing a wafting in the air and drawing attention. Owls have feathers with soft edges, which allow them to fly low to the ground to hunt undetected.

An owl does not have teeth so when it wants to eat its prey it must either swallow it whole or break it up into little pieces. Since owls cannot digest bones and hair it will cough up the remains into what is known as a cast.

Mating and Early Life

Owls are not pack creatures and in fact can be very territorial. Therefore owls eat, hunt, and live alone most of their lives. You may notice that the Great Horned Owl Camera often shows a single owl.

When an owl is ready to mate, it will begin "who-ing" in order to alert any other mature owls around the area that it is, in fact, a viable mate. Since owls are lone creatures, when a male owl courts a female owl it tends to be a tedious process until one can learn to trust the other. Once trust is gained, reproduction is based on how much food is readily available. Most owls produce 2-6 eggs but there have been times that owls can produce up to 14 eggs. Once eggs are ready to hatch, they hatch within two days of each other and stay with both the mother and father until about three months of age. Once old enough to live on its own, an owl will look for a home in either an abandoned nest, a hole in a tree, or if they reside in a treeless location, an established burrow in the ground.

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Great Horned Owl Cam - live owl camera from Montana | Explore.org

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The live owl cam features a Great Horned Owl: A powerful and adaptable bird of prey that has the most extensive range, the widest prey base and the most variable nesting sites of any American owl. Its large yellow eyes, pronounced ear tufts, and white bib distinguish the Great Horned Owl from related species, especially once its unmistakable multi-tone hoot is heard.

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Western Montana, USA

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The Great Gray is one of the tallest species of owls, however, its large size is due to a fluffy and thick plumage, the owl's body is considerably smaller than it appears.

Great Gray Owls-which are also known as Lapland Owls, bearded owls, or spectral owls-are easily identified by a large, rounded face with yellow eyes, and a "bow-tie" around the neck region.

Great Gray Owls live in the dense conifer forests of Canada, the northern United States, northern Europe and northern Asia. In recent years, their habitat has declined due to logging and shrinking populations of rodents.

Great Gray Owls primarily hunt by detecting high-frequency sounds made by rodents rustling in the underbrush. The owl has a broad, circular face that acts like a sort of satellite dish receiver for receiving sound waves. Outlining the owls face is a ring of highly sensitive feathers that funnel sounds to the ear canals located on either side of the head. A thin barrier of bristle feathers divides the two sides of the face, allowing for accurate stereo sound.

Great Gray Owls hunt during both the day and night and will feed mainly on small animals. Gophers, moles, mice, shrews, squirrels and weasels are favorite prey of Great Gray Owls.

Courtship begins in midwinter and occurs when a male approaches a female to offer her a rodent he has hunted.

Nesting occurs in March through May and Great Gray Owls often use the discarded nests of other large raptors such as ospreys, or will nest in tree cavities. Nesting sites are almost always selected within 1 kilometer of an open meadow in which the owls can hunt.

There are typically two to five eggs in a clutch, and incubation generally lasts around 30 days. The male owl hunts for food to sustain the mother owl, who incubates the eggs for the entirety of the period.

Three to four weeks after hatching, the young owls are old enough to climb out of the nest and perch themselves on a branch where they will observe the parent owls hunting. One to two weeks after leaving the nest, the owls are ready for their first flight.

Great Gray Owls have been documented to live up to 40 years in captivity. Shortage of prey caused by habitat destruction is the number 1 cause of death in the wild.

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Great Gray Owl Nest - live owl camera from Montana | Explore.org

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The Great Gray is one of the tallest species of owls, however, its large size is due to a fluffy and thick plumage, the owl's body is considerably smaller than it appears. Great Gray Owls-which are also known as Lapland Owls, bearded owls, or spectral owls-are easily identified by a large, rounded face with yellow eyes, and a "bow-tie" around the neck region.

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Montana Field Guide contains a wealth of information about Montana's diverse species.

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1.  Great Blue Heron (Mrs. Gyde's Favorite!)
2.  American Kestrel
3.  Red-tailed Hawk
4. Osprey
5.  Sandhill Crane
6.  Great Horned Owl
7.  Black-capped Chickadeedeedee
8.  Canada Goose
9.  Black-billed Magpie
10.  Ruffed Grouse
11.  Common Nighthawk
12.  Belted Kingfisher
13. Wood Duck
14. Western Bluebird
15. Cedar Waxwing
16. European Starling
17. Red-winged Blackbird
18. Northern Flicker
19. Western Meadowlark
20. American Robin

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Online bird guide, bird ID help, life history, bird sounds from Cornell

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Featured Browse All Articles Sign Up for Our eNews Get helpful advice, inspiring stories, and beautiful images and sounds Bird ID Skills More Bird ID Articles Feeding Birds More Feeding Birds Articles FAQs & Common Problems

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I'm a huge fan of herons. I think they're among the most awesome and charismatic of birds, and also among the most fascinating in terms of what they get up to behaviourally. Their anatomy and ecology are interesting too. Today I want to say a few things about one heron in particular: the Great blue heron Ardea herodias of North America, the Caribbean, the Galapagos and northern South America. This article appears thanks to encouragement from Kevin Gibbs.

The Great blue heron is a sizeable bird, in cases exceeding 1.3 m in length, 1.3 m in standing height, and 2.1 m in wingspan. Typical birds (not the white ones, on which read on) are generally blue-grey, tinged with violet, on the neck, back, sides and belly. They have chestnut leg feathers ( Hancock & Kushlan 1984). The bill is mostly yellow and plumes grow from the back and lower neck during the breeding season. The iris reddens during the breeding season, and the legs turn pinkish-orange too. Males are larger than females, as is typical for herons.

The Great blue heron is very obviously a close relative of the other Ardea herons, in particular the Afro-Eurasian Grey heron A. cinerea and the South American Cocoi or White-necked heron A. cocoi ( McCracken & Sheldon 1998). All three are regarded as members of the same 'superspecies' by some authors. There's a bunch of other Ardea species, but I have to ignore them here. Beyond this, Ardea is most closely related to Casmerodius and Bubulcus (Sheldon et al. 2000).

What is the Great white heron? The Great blue heron is not just bluey-grey - it also seemingly occurs in a snow-white form, this long being regarded as a separate species called the Great white heron A. occidentalis. Here we come to an area of some disagreement.

Ernst Mayr wrote of his suspicion - on first learning of the 'Great white heron' - that it was "nothing but a locally distributed color phase of the Great blue heron" ( Mayr 1956, p. 71). He noted how museum-based ornithologists of the time (the late 1950s) were inclined to regard the 'Great white heron' as a mere colour phase of the Great blue heron, it being field naturalists who continued to regard the two as distinct. Their arguments for distinction included the alleged shyer nature of the Great white heron (yes, really), its strong association with marine habitats, and the fact that it nests side-by-side with the Great blue heron (err...?). You don't have to be the word's smarterest person to realise that these arguments are not convincing.

However, Mayr (1956) showed how several features did distinguish occidentalis-type birds from herodias-type ones: the white ones aren't just white, they also have proportionally larger bills and lack occipital plumes (or, have them in much reduced form, anyway). There's also an unpublished project which finds data from across the skeleton showing that occidentalis-type herons can be distinguished (mostly by size) from herodias-type ones, even the very biggest Great blues that occur alongside occidentalis-type herons in Florida (Zachow 1983). Furthermore, occidentalis-type herons are associated with the Florida Keys, an observation consistent with the idea that they are a distinct population of some form, not just a randomly occurring mutation that can occur anywhere across the Great blue heron's range.

And, while there is a heron that seems like an intermediate between 'Great white herons' and standard Great blue ones - it's called Würdemann's heron and was originally considered another distinct species ( A. würdemanni) - its existence is by no means inconsistent with the idea that the 'Great white heron' is a distinct phylogenetic entity, merely one that hybridizes with herodias-type herons wherever the ranges of the two forms overlap. Many animal populations universally considered 'good species' hybridise with closely related ones where they overlap (random examples: wolves and coyotes, Grevy's zebra and Plains zebra).

Add all of this up, and the general idea has persisted that the Great white heron is at least a 'subspecies' of the Great blue, and something more concrete (as much as anything can be in phylogenetics and taxonomic identity) than a 'morph' or 'colour form'. The idea is even out there that it should be regarded as a distinct species (McGuire 2002). I personally think that the case for taxonomic/phylogenetic distinction looks reasonably good: the Great white heron is, after all, a distinct phylogenetic entity, and this should be marked in some way. Distinct species? Well, maybe not... But a distinct subset of the entity we call Ardea herodias? Well, maybe.

Where to live and what to eat. Herons are mostly associated with freshwater wetlands, and the Great blue heron typically haunts marshes, swamps, and river and lake edges. However, a key aspect of heron success is flexibility and the species also frequents mangroves, tidal mudflats and beaches. In some places - most notably the coasts of Mexico and Florida - it readily hunts in the surf and even does daredevil things like use floating kelp as a foraging platform.

The typical style of predation used by herons is pretty well known: they stand still in shallow water, wait for fish to come within range, and then throw the head and neck forward such that they impale prey with the spear-like jaws. This action is known simply as a 'bill stab'. The Great blue heron hunts this way, and the bulk of its diet (as much as 98% in some studies) and time spent hunting involve this 'conventional' fishing style. Its large size means that it consistently captures fish larger than those caught by other heron species ( Willard 1977), a classic example of niche partitioning in places where the Great blue heron lives alongside smaller species. It often hunts at night in some places.

It also does several other things that most other herons typically do not, including hovering before dropping (feet-first) to pick prey off the surface of the water, and swimming in deep water (yes, herons can swim). Great blue herons have also been observed to pick up dead fish from the surface of very deep water while flapping, dangling the legs and stretching the neck forwards, the implication being that strong winds were able to help them stay aloft while in this position (Reese 1973). The Great blue heron will also flycatch - that is, grab flying prey right out of the air. On that note, there are various records of herons - mostly involving the Grey heron A. cinerea - where the birds were seen grabbing flying starlings and even hirundines (Berthold 2004).

The Great blue heron's diet isn't limited to fish though, and nor are herons in general. Insects, amphibians, reptiles, mammals and birds of many species are recorded dietary items of the Great blue heron and the species often hunts in terrestrial environments, sometimes predating extensively on rodents. Individuals on the Florida Keys and Galapagos islands "frequent human habitation for scraps of food provided for them" ( Hancock & Kushlan 1984). Indeed, while we think of herons as aquatic foragers, they can very easily switch to land-based hunting and frequently do so. Furthermore, members of the group could easily make the evolutionary transition to full terrestriality if conditions favoured it.

Large prey, very large prey, and the unfortunate consequences. Among the more surprising prey items eaten by Great blue herons are rails and stilts ( Olsen & Johnson 1971). Rivers & Kuehn (2006) described a case in which a Great blue heron attacked and killed a swimming Eared grebe Podiceps californicus (I'll just leave the terms 'Black-necked' and ' P. nigricollis ' here and leave you to sort it out for yourself. Yes, I'm using 'post-split' terminology). However, after attempting to swallow the dead grebe (which weighed 255 g), the heron eventually gave up. Rivers & Kuehn (2006) reported another observation in which an Eared grebe caught by a Great blue heron eventually escaped, apparently unharmed.

On the subject of large prey items, Great blue herons sometimes overestimate their abilities to tackle and swallow prey and can choke and die as a result. Long-time readers will recall my article from 2009 on the individuals who choked to death after attempting to swallow large Pacific lampreys Entosphenus tridentatus ( Wolf & Jones 1989). Other cases of choking have involved carp, bullheads, frogs and snakes (see citations in Wolf & Jones 1989). On the subject of Great blue herons vs other birds, I should also mention the case in which a Californian Great blue heron was seen to attack and kill an American coot Fulica americana, apparently with no intent to eat it (Rivers & Kuehn 2006).

As always, there's much more that could be said. I haven't even mentioned the breeding and nesting behaviour of this bird, their display behaviour and ritual postures, nor the 'subspecies' that have been recognised in addition to occidentalis. But I think that will do for now. I must write about herons in general sometime soon - such a fascinating bunch.

For previous Tet Zoo articles relevant to some of the material covered here, see...

Refs - -

Berthold, P. 2004. Aerial "flycatching": non-predatory birds can catch small birds in flight. Journal of Ornithology 145, 271-272.
Hancock, J. & Kushlan, J. 1984. The Herons Handbook. Croom Helm, London and Sydney. Mayr, E. 1956. Is the Great white heron a good species? The Auk 73, 71-77. McCracken, K. G. & Sheldon, F. H. 1998. Molecular and osteological heron phylogenies: sources of incongruence. The Auk 115, 127-141.
McGuire, H. L. 2002. Taxonomic status of the great white heron (Ardea herodias occidentalis): an analysis of behavioral, genetic, and morphometric evidence. Final Report. Florida Fish and Wildlife Conservation Commission, Tallahassee.
Olsen, C. S. & Johnson, H. M. 1971. Great white heron captures and eats Black-necked stilt. Auk 88, 668.
Reese, J. G. 1973. Unusual feeding behaviour of great blue herons and common egrets. The Condor 75, 352.

Rivers, J. W. & Kuehn, M. J. 2006. Predation of Eared grebe by Great blue heron. The Wilson Journal of Ornithology 118, 112-113.

Sheldon, F. H., Jones, C. E. & McCracken, K. G. 2000. Relative patterns and rates of evolution in heron nuclear and mitochondrial DNA. Molecular and Biological Evolution 17, 437-450.
Willard, D. E. 1977. The feeding ecology and behavior of five species of herons in southeastern New Jersey. The Condor 79, 462-480. Wolf, B. O. & Jones, S. L. 1989. Great blue heron deaths caused by predation on Pacific lamprey. The Condor 91, 482-484.
Zachow, K. F. 1983. The great blue and great white heron (Aves: Ciconiiformes: Ardeidae): a multivariate morphometric analysis of skeletons. Unpublished thesis, University of Miami, Florida.

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I'm a huge fan of herons. I think they're among the most awesome and charismatic of birds, and also among the most fascinating in terms of what they get up to behaviourally. Their anatomy and ecology are interesting too.