Posts Tagged ‘identification’

Bird Topography – The Head

By

Thursday, November 15th, 2012

Bird Topography – The Head by Drew Weber

Understanding topography, or the different external features, of a bird is an important step in identifying different closely related species. The head is a good place to start because there are many separate feather tracts that give rise to different physical appearances. The colors of the different feather tracts gives rise to the unique appearance of each species. Below we’ll look over the different characteristics of a birds head along with species that show distinctive features on those tracts.

Crown

Tufted Titmous

Tufted Titmouse, adult © Arthur Morris/VIREO

 

The crown is the top of the head, and like most other feather tracts, birds can raise and lower these feathers. Some birds have longer feathers on their crown which changes their appearance by giving them a crest like the Northern Cardinal and Tufted Titmouse. Other species without an crest can still raise those feathers, creating a slightly peaked appearance when they are displaying or agitated such as when Ruby-crowned Kinglets flash the usually hidden red feathers in their crown.

Supercillium

Northern Waterthrush

Northern Waterthrush, adult © Steve Mlodinow/VIREO

 

The supercillium is the white line that arches over the eye one the Northern Waterthrush, as well as many other species including many of the sparrows. The supercillium runs from the base of the bill to some point near the back of the head. On most species, this supercillium is white, or some lighter color than the surrounding feathers. The shape, color and size of a supercillium can be a key identification in separating confusing species like Northern and Louisiana Waterthrushes.

Eye line

Blue-winged Warbler

Blue-winged Warbler adult male, breeding © Garth McElroy/VIREO

 

Eye lines are prominent features on many species. Interestingly this eye line is invariably dark, possibly giving some glare protection to birds, much like the black grease baseball and football players swipe under their eyes. Late in the fall, it can be tricky to separate Orange-crowned and Tennessee Warblers. Looking at the face and seeing an eye line would be a strong indicator of a Tennessee Warbler.

Eye-ring

Connecticut Warbler

Connecticut Warbler, adult male © Glenn Bartley/VIREO

 

A ring of feathers around the eye, often light in color and very useful for identification. Not all eye-rings are created equal, some species have bold complete eye-rings, while other similar species have a split ring around the eye such as MacGillivray’s Warbler. Eye-rings are particularly useful when you are identifying tricky flycatchers– some show a hint of the eye-ring, others have prominent round eye-rings and some have eye-rings with a tear drop shape towards the back of the eye. These subtle differences can take a while to notice but are crucial to identifying one of these cryptic species if it is not vocalizing.

Auriculars

Blackburnian Warbler

Blackburnian Warbler adult male, breeding © Doug Wechsler/VIREO

 

The auriculars, or ear coverts, are a group of feathers that covers the side of a bird’s head where the bird’s ear openings are located. Several of the warblers such as Blackburnian Warbler show a dark patch in the auriculars and Vesper Sparrow has darker brown feathers that outline the auricular region. The auriculars are a prominent feature on a birds face and therefore probably one of the first things many notice as it defines the face.

Nape

Chestnut-collared Longspur

Chestnut-collared Longspur adult male, breeding © Greg Lasley/VIREO

 

The nape goes from the back of the head and lays over some of the upper back feathers. One many birds, the nape blends in with both the back and the rest of the head. However some species have bold napes like the chestnut on a Chestnut-collared Longspur which aid in quick identification when you see it. A group of species where the nape can aid in identification is the sharp-tailed sparrows (in the genus Ammodramus). These small sparrows are secretive and often pop out of the vegetation only briefly, so a look at a purple spotted nape can identify a Le Conte’s Sparrow, an olive-green nape points to Henslow’s Sparrow and a gray nape would narrow it down to Nelson’s, Saltmarsh, and Seaside Sparrow.

Get to know the feather tracts of the face to boost your identification skills when you are out in the field. This knowledge will quickly add to the number of solid features you can use to separate similar looking birds when you might only get a glimpse of them.

Finding Fall Warblers

By

Friday, September 14th, 2012

Finding Fall Warblers by Drew Weber

Finding warblers in the fall can be much trickier than finding them in the spring. Males are singing less often because they are no longer attempting to attract mates, and most of their vocalizations are difficult-to-identify chips. These chips are actually the best thing to clue in on, as they can often lead you to a feeding flock of warblers. The feeding flocks can vary in size, but when you locate one warbler there is a good chance that several others are nearby.

warblers

Black-throated Blue Warbler adult male, breeding © Arthur Morris/VIREO

The first thing to do is find some suitable habitat. Fall warblers often concentrate along the edges of woods where early morning sun is hitting the trees and warming the air, increasing the activity of insects which the warblers are seeking out. Walk along the forest edge listening carefully for chips. In addition to listening for warbler chips, pay attention to any chickadees. Warblers will often forage in a loose flock with chickadees. Since the birds aren’t vocalizing as much, take your time as you scan the area and walk slowly. Also don’t be afraid to backtrack as a small flock can emerge from the woods and forage along the edge with no warning after you passed it.

Black-capped Chickadee

Black-capped Chickadee adult, Rocky Mountain © Rolf Nussbaumer/VIREO

Another habitat type you should check out for fall warblers are fields of dense goldenrod. Tennessee, Orange-crowned and Wilson’s Warblers can all be found in this type of habitat as they forage in the goldenrod. Successional habitat with a mix of smaller trees and shrubs can also provide ideal habitat for finding warbler feeding flocks.

warblers

Wilson’s Warbler adult female, Eastern © Claude Nadeau/VIREO

Looking for fall warblers can be very rewarding because of the patience it can require. It is very exciting to find a mixed flock of 6 different species of warblers and get great looks at them as they forage at eye level, rather than in the treetops as is typical in the sling. And getting a good look is important.

Fall warblers get a bad rap for being hard to identify. They also have the reputation of being less colorful than the spring warblers. There are a couple reasons for this. First of all, spring migration is a quick and hurried affair as birds race northward to stake out territorial claims to some prime breeding habitat. In all the rush, we generally only manage to see the birds that are singing…males with their distinctive bright plumage.

warblers

Cape May Warbler adult male, breeding © Adrian & Jane Binns/VIREO

In the fall, migration is a much more leisurely event. The warblers take their time and stop for days at a time to feed and replenish the reserves they require for their long flights. This gives birders a chance to see females as well as males, adding an additional plumage variation that has to be identified. Also, each successful pair of birds raised maybe 2-5 young, meaning there are now more immature birds than adults. The plumage of immature males and females are often different as well.  Generally young males look similar to adult females, while immature females are even drabber colored.

warblers

Black-throated Green Warbler immature male (1st spring) © Gerard Bailey/VIREO

This means that in the fall, a birder often needs to be familiar with at least three, and sometimes four different plumages of a bird to be able to correctly identify each warbler they see. Adult males are still mostly in their bright breeding plumage, young males and adult females are drabber and sometimes hard to differentiate, and young females are the drabbest.

warblers

Cape May Warbler immature female (1st winter) © Rob & Ann Simpson/VIREO

If you get a chance to study females and immatures closely, you will discover although their colors aren’t as gaudy as the spring males, there is still a lot of color on many of the young warblers. Young Chestnut-sided Warblers, for example, have a beautiful lime-green back.

warblers

Chestnut-sided Warbler immature female, 1st winter © Gerard Bailey/VIREO

So, are fall warblers really harder to identify? The answer is yes, but a species often shares specific characteristics between all the different plumage. Learn these shared characteristics and identification will be much easier. Spend some time getting to know the fall warblers, and I am sure you will enjoy them as much as I do.

Hawk ID, Part 4: Buteos

By

Tuesday, September 11th, 2012

Hawk ID, Part 4: Buteos by Josh Haas

Hawk ID, Part 3: Accipiters

Hawk ID, Part 2: Falcons

Hawk ID, Part 1: ID Techniques 101

The buteos are the open land, soaring hawks you see many times along highways and open fields.  Most tend to be opportunistic but from a distance, they can be tough to ID as many are comparable in size and have similar coloration.  This is another reason flight ID is key for this family.

Broad-winged Hawk © Josh Haas

Broad-winged Hawk © Josh Haas

The buteos we’ll go over include the Broad-winged Hawk, Red-shouldered Hawk, Red-tailed Hawk, and the Rough-legged Hawk.  The Broad-winged Hawk is the migrant that relies on kettles (swirling groups of birds taking advantage of rising heated air) and weather patterns for flights (specific winds, pressure, etc.)  They mostly migrate in groups, many times well over 1,000 strong.  As a typical buteo, this bird has broad wings without a very long tail.  In flight, this bird’s wing flap is choppy and stiff.  In a soar, the wings are held flat and in winds, the bird will flap to maintain balance.

Red-tailed Hawk

Red-tailed Hawk © Josh Haas

In comparison, the Red-shouldered Hawk can be much larger and stouts a wing flap that is stiff, making the bird appear to be batting the air.  While the Red-tailed has a quick wing flap relative to its large muscular body size, its flap is from the body and the whole wing is used.  Comparing the Red-Shouldered to a Red-tailed, when thrown off course in winds, the Red-shouldered has to work to get back on course with several wing flaps and adjustments whereas the Red-tailed will typically only make a couple of flaps and is back on course.  The Red-shouldered also has a peculiar glide where its wings go straight out and then curve downward from the wrists on.  When comparing the glide to a Rough-legged, who has a strong upward wing shape, especially from the middle to outer ends, this contrast can make for obvious ID.  Watching a Red-tailed in a glide, there is only a slight upward feel to it, giving the appearance of a slight dihedral.

Rough-legged Hawk

Rough-legged Hawk © Josh Haas

The wings of the Rough-legged Hawk are quite long and uniformly broad.  The tail is also long and broad.  In flight, the Rough-legged retains its long-winged look and the wing beat is very steady.  This buteo rarely flaps in series, meaning it doesn’t have even pumps and glides.  If it does show a pump and glide pattern, it’s typically more pump.  Rough-leggeds are powerful fliers and they know it.  They do not rely on thermals and often power through watches early and late in the day.

Buteos are typically a family that is easy to identify.  The tricky work comes when trying to narrow further to an individual species.  Be sure to look for subtle differences in flight, soars and glides.  It’s also helpful to have a cheat sheet in your pocket with one-line tips for each species.  You can quickly reference this from time to time throughout the day to remain sharp!

Hawk ID, Part 3: Accipiters

By

Wednesday, September 5th, 2012
Sharp-shinned Hawk

Sharp-shinned Hawk © Josh Haas

Hawk ID, Part 3: Accipiters by Josh Haas

Hawk ID, Part 1: ID Techniques 101

Hawk ID, Part 2: Falcons

The Accipiters are the family that usually gives birders the most problems.  When it comes to Sharp-shinned Hawks, Cooper’s Hawks, and Goshawks, they all can look identical; especially when perched at a distance.  For this reason, it’s even more important to ignore field mark ID and go straight to flight characteristics.

The smallest of the three, the Sharp-shinned Hawk can literally look tiny.  In flight the Sharpie has an extremely fast wing beat that is more from the wrist, than the shoulder.  It’s very snappy and typically has a 3-4 flap, then glide pattern as it makes its way past the Hawkwatch.  Many times as Sharpies fly over, you will also notice their shoulders are many times thrown forward making their heads appear smaller.  In contrast, Coopers Hawks flap more from the shoulder making it look like their entire wings are flapping.  They also tend to have their shoulders flat making their heads appear as if it’s thrown forward.  While most books say to only look for a squared off tail to decipher a Sharpie from the rounded tail of a Coop, any Hawk watcher would admit that a surprising amount of Sharpies come through with rounded tails.  Likewise, many Coops also come through with squared tails.  Because of this, using the tail as a definitive ID technique is not recommended.  While the Northern Goshawk is an Accipiter, it’s a giant.  This large bird can actually look like a buteo (open land soaring raptor).  In fact, a commonly used rule of thumb with Goshawks is if it first appears in the sky to be a buteo (similar to a Red-shouldered Hawk for example) but then turns out to be an Accipiter, it’s without a doubt, a Goshawk.

Northern Goshawk Flight Hawk

Northern Goshawk Flight © Josh Haas

 

 

 

 

 

Accipiters are extremely difficult to ID, especially the Sharp-Shinned and Coopers but with some practice and repeated times at sites known for large Accipiter movements, you can start to get these birds down and begin to move on to other families of Raptors.  Next up, the Buteos…

Mission: Impossible – the Ground Beetles

By

Tuesday, September 4th, 2012

Mission: Impossible – the Ground Beetles by Jungle Pete

Pasimachus ground beetle

Pasimachus ground beetle © Jungle Pete

My mother, a park ranger, once held out a cone from an unknown tree and asked a state forester if he knew which tree it came from. “Some kinda conifer”, he answered, as if that was sufficient. He wasn’t wrong. The cone did come from a coniferous tree, but the answer was as helpful as saying “food” when someone asks “what’s for dinner?”

My mother was hoping for the specific tree. Did the forester know the answer or not?  I hardly know anything and nature proves that to me daily with new mysteries. For example, why one morning was there a Ground Beetle hanging from a web-like snare from the bumper of my car? These are large, hefty beetles. Who caught it? And what type of beetle is it? I’ll give you a hint. You’re not going to find out because I don’t know.

I asked an insect nerd, I mean entomologist, which species it might be and considering there are over 425 different species of ground beetles, I was content to have it narrowed down to the Pasimachus, a genera with at least five indigenous species in Florida. From there he said it was impossible to tell with the photograph provided.

Pasimachus ground beetle

Pasimachus ground beetle © Jungle Pete

Most of the 40,000+ beetles in the world have hardened elytra that cover over and protect the wings. The Pasimachus ground beetles are flightless and the elytra are fused into a firm shell. They spend their time on the ground, in and under logs and leaf litter foraging for caterpillars, other larvae and other ground insects.

How this beetle came to be ensnared, flailing its limbs in the breeze like Ethan Hunt on a mission is beyond me. If it was trapped in a spider’s web, I wasn’t curious enough to look up under my car to find out which kind.

It would have been nice to offer you a genus and species name, but the beetle biologist took me as far as I could go. “Some kinda Pasimachus” would have to do. Sometimes identifying insects is a mission: impossible.

Hawk ID Part 1: ID Techniques 101

By

Tuesday, August 7th, 2012

Hawk ID Part 1: ID Techniques 101 by Josh Haas

With mid summer upon us and Fall around the corner, I thought it’d be fitting to start a series of Hawk ID blogs in hopes of helping aspiring Hawk enthusiasts with ID’ing these tough birds.  The goal will be to give ID techniques both individually and in family groups to help with differentiation between birds.

Broad-winged Hawks

Broad-winged Hawks © Paul Cypher

The first thing to do is throw field mark ID techniques out the window.  With hawks, it’s all about flight characteristics.  This can be difficult because we’ve been engrained to use field marks for ID for so long.  We tend to rely on this so heavily and refuse to let it go.  Flight ID is all about looking for things like body shape, wing shape, how the bird is flapping, whether the wings are held up when soaring (in a dihedral), and how they’re holding their wings in a glide.  By looking at these things and not worrying about field marks, you can identify individual species with certainty.  Of course, that sounds easy but as with everything it takes lots of practice.  Depending on your locale, one of the best things to do is find a local Hawkwatch during either the Spring or Fall and go where the higher concentration of birds will be.  This really can up the odds of retaining what you learn as you have the chance of seeing many birds of several species in a small amount of time.  It takes years to really get this Hawk ID thing down but when you start to get it, it’s one of the most gratifying in birding.

Red-Shouldered Hawk

Red-Shouldered Hawk © Josh Haas

As with everything you’re trying to get better at, birding with birders better than you is very helpful.  Spend time listening to what they’ve learned over the years and work hard scanning the skies for distant raptors.  It’s important to lay your pride down and be willing to call out birds full well and knowing that your mentor may correct you if you’re wrong.  Don’t let that get you down, this is just part of the learning process and an important one.  Stay tuned for Part 2 where we’ll tackle the falcons!

 

To learn more about Raptors check out: Identifying Raptors in Flight

Easy Answer

By

Thursday, May 10th, 2012

Yellow-headed Blackbird by Tom Wood

Sometimes it can be challenging to identify a bird over the phone, but this was an easy one. The caller described a “black bird with a yellow head”. “That’s a Yellow-headed Blackbird!” I explained. There was silence on the other end of the line. I think the caller thought he had reached the biggest smart-alec in Arizona. “No, really. That’s what they are called.” I wish all bird names were so descriptive. As if the name Yellow-headed Blackbird were not obvious enough, the scientific name, Xanthocephalus xanthocephalus , literally means “yellow head yellow head”.

Actually, it’s a good thing this blackbird has such a striking field mark. If the head were not so bright or the wing patches so distinctive, the bird might have been named after another subtle field mark seldom mentioned. The bright yellow cheerio of color around the vent could have given us a truly tasteless common name.

Checklists and field guides remind us that taxonomically orioles and blackbirds are closely related, but the Yellow-headed Blackbird truly shows that affinity. You never, however, see flocks of thousands of orioles wheeling overhead and settling into a marsh. A raucous flock of Yellow-headed Blackbirds are nowhere near as melodious as an oriole or even their red-winged brethren. Here in southern Arizona we only see Yellow-headed Blackbirds in the winter, often in the same marsh where we watch Sandhill Cranes. We’ve seen bare trees so full of Yellow–headed Blackbirds they looked like lemon trees. We’ve also often seen them in the San Luis Valley of southwestern Colorado, at the Monte Vista National Wildlife Refuge where they nest in the cattails along the Avocet Trail. The males will mate as many as six or seven females, but will only help tend one nest. They often nest in mixed colonies with Red-winged Blackbirds. In late summer when they arrive in our area, some show only a glimpse of their breeding season glory. But by next spring they will be unmistakably a “Yellow-headed Blackbird”.

-Tom Wood

Variations in Rough-legged Hawks

By

Wednesday, April 11th, 2012

Rough-legged Hawk by Lisa Densmore

Location: Lima, Montana

If you’re wondering where Lima (pronounced LI-ma, like the bean), Montana is, you are not geographically challenged. With due respect to the residents of this small ranching community in the southwestern part of the Treasure State, the only reason Lima entered my life was because we passed through it on the way home after a weekend in Idaho. I’m not apt to forget it. It took a long time to travel through Lima, not due to traffic – we might have seen two cars in two hours on the open road on which we traveled – but because we saw so many Rough-legged Hawks (Buteo lagopus).

Rough-legged Hawk by Lisa Densmore

They perched everywhere, on the irrigation pipes, on the tops of electrical poles, on fence posts… In this hawk-rich environment, I gained a new appreciation for this rodent-eating raptor, which is on the large side for a buteos, averaging 19 to 24 inches tall. With so many of the species in one place, I realized how much variation there could be from one to another. The typical Rough-legged Hawk has a dark belly, though it may be blotchy. A black patch normally shades the carpal joint where the wing bends, but not always or it might be very small. The wings have lots of white on the underside, and its white tail has a black band near its end, but the black morph has a mostly dark tail. ID-ing a Rough-legged Hawk can be challenging if you don’t already know the bird. It’s more diverse than Grand Central Station during rush hour. Fortunately, it lives in a less populated environment than mid-town Manhattan, making it easy to spot.

I enjoyed seeing its color variations. The phenomenon is not unique to Rough-legged Hawks. While each avian on my AudubonGuides.com app has a common look, variations occur. Have you seen birds-of-a-color that really are not?

Adolescent Eagle ID

By

Tuesday, March 20th, 2012

Golden Eagle by Jack Ballard

Here in Montana, eagle sightings seem much more frequent in winter than in the summer. It’s not that eagles are more abundant. They’re just easier to see. Their big, brown bodies show up more readily in leafless trees. Carrion along the roadways brings them within eyeshot of traveling motorists. On a recent, two-hour drive through the south-central part of the state, I spotted over a dozen eagles.

Both Bald Eagles (haliaeetus leucocephalus) and Golden Eagles (aquila chrysaetos) grace the big blue skies of my home state. Adult birds of the two species are easily distinguished from each other. But like human teenagers seeking to blend with their peers, adolescent eagles are copycats. For the first year of life, immature Bald and Golden Eagles can be maddeningly difficult to differentiate.

Bald Eagle immature (2nd year) © Arthur Morris/VIREO

But a seasoned ornithologist’s trick helps. Rather than focusing on a single characteristic to separate the species, evaluate several diagnostic features. Immature Golden Eagles, though sporting mottled brown and white plumage like their bald cousins, display a more sharply defined white band on the tail. Their legs are also feathered to their feet, while Bald Eagles have bare lower legs. Golden Eagles have a smaller, slimmer head. Juvenile Golden Eagles often sport the golden mantle of their kind on the head and neck.

Recently, I had the opportunity to snap a few quick photos of an immature eagle as it winged away from a road. Although the experience was fleeting, by focusing on a variety of features, I determined the teenager to be a Golden Eagle, a fortunate creature that never has to worry about becoming bald.