Red-shouldered Hawk in Explore the Wild.

People who are not familiar with the species often look at me with confused eyes when I tell them that the hawk perched in the trees before them in the swamp here at the Museum is a Red-shouldered Hawk. Why would they name this hawk “red-shouldered,” and where are the red shoulders?

A Red-tailed Hawk has a brick-red tail. That name makes sense. The Red-shouldered Hawk (RSHA) has a reddish belly and chest. Why not name the hawk Red-bellied, or Red-breasted Hawk? Even the Latin name for this hawk doesn’t give a clue as to why it’s named red-shouldered, Buteo lineatus means lined or striped hawk.

RSHAs have a reddish patch of feathers, which comprise most of the secondary upper wing coverts, that stretch from the actual shoulder of the wing to the wrist. The red “shoulder” is not always visible on perched birds.

The red patch is not always obvious when the bird is perched (same bird as above).

It’s a different story when the birds take flight or have their wings stretched out to preen, or when dealing with prey.

The reddish colored upper wing coverts (so-called shoulder) are obvious in flight (photo - 10/09).

This RSHA has just dropped in on a frog in the Wetlands. Note the red wing patches (photo - 4/10).

So, now you know why the Red-shouldered Hawk is called a “Red-shouldered” Hawk. But wait, what are secondary wing coverts?

Coverts are relatively small feathers that overlap and cover the bases of the larger flight feathers on a bird’s wing, the primaries and secondaries. The coverts that cover the bases of the primary feathers are called primary coverts. You can probably guess what the coverts that cover the bases of the secondaries are, that’s right, secondary coverts.

There are coverts on both upper and lower surfaces of the wing to cover both sides of the flight feather bases. The coverts are further divided into groups as the greater primary covers, median primary coverts, lesser primary coverts, marginal primary coverts…there are also coverts that cover the bases of the tail feathers…their purpose is to create a continuous, smooth surface across the wing, or tail, which aids considerably in the act of flying, less drag.

There were a few Red-tailed Hawks about too.

As I’ve often said in this journal, I see Red-tailed Hawks at least once a week during winter here at the Museum but there’s a period during the summer when I may not see them at all. Part of the reason for their summertime leaves of absence may be the Red-shouldered Hawks.

When the red-shoulders have breeding-season hormones flowing through their bodies, the larger redtails have to be moved along. The redtails are apparently perceived as a threat to the red-shoulders’ successful nesting. Although I’ve witnessed these rousts of the redtails by the smaller red-shoulders many times in the past, my attempts at getting images of a redtail roust have been less than stellar.

The following sequence was shot by Animal Keeper Sarah the same day as the Great Backyard Bird Count (2/18) when there were six Red-shouldered hawks aloft at one time.

This is a Red-tailed Hawk.

This is a Red-shouldered Hawk, high above the redtail.

The red-shoulder turns,

tucks, and...

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The redtail (lower left) leaves the scene while the red-shoulder glides off to return to what it had been doing, soaring on the wind.

Now, that’s what I’m talkin’ ’bout!

Two Pine Siskins share the feeder with two American Goldfinches on Saturday, 19 February (the siskins are the two middle birds).

The requirements for participating in the Great Backyard Bird Count are a willingness to count birds in your backyard, favorite state park, or other location, and a willingness to write down what you see and submit it to the above mentioned project managers.

Often difficult to see in both in life and this picture is the Brown Creeper. Creepers cling to the sides of trees woodpecker-style, climbing up the trunks and branches to seek out insects and other invertebrates to eat (2/20/11).

I conducted the count by myself on Friday the 18th of February here at the Museum in Explore the Wild, the Dinosaur Trail, and Catch the Wind. Ranger Kristin counted with me the following day, and took on the job of counting by herself on the 21st, the final day of the four day count period. Other duties called both of us away on Sunday, the 20th of February.

This Red-shouldered Hawk (in its second year of life-SY) is one of 6 seen soaring over the Wetlands during the Great Backyard Bird Count (2/18/11).

We saw two species which can be a challenge to observe on any winter’s day, but on the count day they were a special surprise, Pine Siskin and Brown Creeper, both new birds for Kristin. And, on Saturday the 18th there were as many a six Red-shouldered Hawks soaring above the Wetlands at one time.

The same day, I saw both male and female Cooper’s Hawks soaring together. After a brief courtship display the male took off, presumably, to look for some of Durham’s downtown pigeons, while the female headed off to the pines just north of the Wetlands. It looks as though there’ll be another nest in our midst again this year.

This male Northern Cardinal belts out its song from a perch along the Dinosaur Trail. Common, but beautiful to both see and hear.

We averaged 33.3 bird species for the period (34 birds the day I counted alone, 36 the day of the joint count, and 30 birds when Kristin soloed). Not bad totals for a habitat within Durham’s city limits.

What's this Northern Mockingbird looking at?

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The object of the mocker's attention is two Red-tailed Hawks taking advantage of the perfect soaring weather of January 29 to rehearse their courtship flight.

]]> http://blogs.ncmls.org/greg-dodge/2011/02/02/whats-he-looking-at/feed/ 2 http://blogs.ncmls.org/greg-dodge/2010/04/16/no-fly-zone/ http://blogs.ncmls.org/greg-dodge/2010/04/16/no-fly-zone/#comments Fri, 16 Apr 2010 14:22:26 +0000 Greg Dodge http://blogs.ncmls.org/greg-dodge/?p=5283

A Red-tailed Hawk leisurely sails over the Wetlands on 15 April.

The hawk peers over its right shoulder at something approaching from above and behind.

A while back I mentioned that Red-tailed Hawks are not often seen over the Museum’s outdoor areas during the summer months. Its not quite summer yet, but trouble is already brewing for the big red-tails.

A crow sneaks in from the rear.

The hawk wheels around to avoid the crow's dive-bombing aerial attack.

Crows seem to delight in harassing any hawk or owl they come across, especially during the nesting season when the crows are raising their young.

Another crow joins in as the hawk turns, talons drawn and ready.

The crows are brazen, but they’re not dumb, and these two gave up their pursuit once the hawk left “their” airspace.

Keep your eyes to the skies!

A few hours after posting the above, I was out in Catch the Wind and observed a pair of Red-tailed Hawks performing their aerial courtship flight. I didn’t get the whole sequence of events on film (digital), and the birds were way up there requiring a bit of enlargement, but hopefully you’ll get the gist of what the birds are doing.

One bird (on right) comes in from above the other bird, which is slowly gliding into the wind

The upper bird lowers its talons and drops in closer.

It's just about at this point where the lower bird inverts itself with talons raised, the two locking talons and tumbling through the air.

The next image should show the birds tumbling through the air, but unfortunately the birds went behind a group of tall pines and we’ll have to wait till next time for that one. Sorry.

Later the same day, down on the ground, a group of some fifty American Robins were feasting on worms and other invertebrates.

Some of the robins that have stopped in to rest and feed on their journeys north.

A closer view of one of these very familiar, handsome thrushes.

Although our avian visitors were eating invertebrates at the time, American Robins relish berries and other small fruit. Northern Mockingbirds (NOMOs), who also like fruit, and who stake out and protect winter territories where their food source is plentiful, get rather anxious when a group of fruit eating birds settles in nearby.

This Northern Mockingbird appears a bit bothered by all of the robins that decided to stop and feed in its territory next to the Ornithopter.

See you outside!

Turkey Vultures are a daily sight as they soar, dip and bank across the Museum’s airspace.

Note the small head, gray flight feathers, and rather long tail on this Turkey Vulture sailing over the Museum.

The slightly smaller Black Vulture, while seen at least once a week here at the Museum, is not as frequently encountered as the Turkey Vulture.

A short tail, small head, and white or gray primaries (the feathers at the tip of the wings) are trademarks of the Black Vulture. Black Vultures flap their wings more often, and more rapidly, than do their larger relatives, Turkey Vultures.

Hardly a day passes without seeing or hearing a Red-shouldered Hawk at the Museum. They are most often encountered while they’re perched in the woods silently watching below for prey.

A Red-shouldered Hawk sits quietly in the swamp between Catch the Wind and Explore the Wild.

Red-tailed Hawks are seen above at least once a week in winter, but there is a two month period during summer when they may not be seen at all. Whenever they do show up, a Red-shouldered Hawk is often there to greet and escort them out of the airspace.

Although larger and more powerful than Red-shouldered Hawks, Red-tailed Hawks are often chased out of the Museum's airspace by the smaller hawk.

This Cooper's Hawk was seen January 28th hunting over Catch the Wind.

Copper’s Hawks have successfully nested here at the Museum for the past two years. I see one of these brazen, bushwhacking, aerial hunters nearly every week of the year, certainly every month. Last week was a double; I saw one (most likely the same hawk) on two different days. Each time, the hawk was hunting from above, settling down into the pines north of the Lemur House.

On February 3rd, a tap-tap-tap-taping sound high in a Loblolly Pine in Catch the Wind signaled the workings of a Brown-headed Nuthatch excavating a nest hole. A pair of these tiny pine dwelling nuthatches had dug two holes in a pine not fifty feet from this location last year, only to give it up (or lose it) to a pair of Carolina Chickadees several weeks later.

One nuthatch quickly exits the hole as the other waits to inspect his handywork.

This pair seems to be a bit ahead of themselves. Last year’s nuthatches were first spotted on February 20 as they had just begun excavation. From the apparent depth of the current hole it appears as though they’ve been working on this one for several days, if not more.

I’ll keep you posted on their progress.

Ravens are large birds, much larger than crows. I would compare their size to that of a Red-tailed Hawk, although their wings are not as broad as the hawk’s wings. Their call is distinctive, especially the croaking call. Listed as Very Rare in our area (Triangle), they are being reported with increasing regularity. I’ve seen a raven on more than one occasion at Occoneechee Mountian Natural Area in Hillsborough, NC but not here in Durham.

Upon the realization that there was a raven nearby, I halted my futile attempt at photographing Butter-butts (Yellow-rumped Warblers) and went off to investigate. The call had come from the area between Catch the Wind and Explore the Wild, above the Lemur House. As I walked up the trail I saw, through the pines, a large black bird fly off in a southerly direction. The bird had the unmistakable wedge-shaped tail of a raven. I quickened my pace, I wanted a photo.

As I came up through Catch the Wind I saw the raven harassing a Turkey Vulture beyond the trees near the Traveling Seeds Exhibit. The bird was moving farther away from me. I moved faster.

A minute (hours) passed before I again saw the raven, this time the bird was quickly moving towards the southwest and was some distance from where I stood. I managed to squeeze off two shots before it disappeared over the pines. Unfortunately, neither image is Pulitzer material, but they’ll have to do.

Common Raven flying over Museum.

From the direction that the bird was heading it must have flown right over the main building of the Museum.

The following day I was alerted by a radio call from Joe Nucilli of the Facilities Department that there was a group of vultures hanging out near the swamp between Catch the Wind and Explore the Wild. I was on my way.

As I walked upon the scene, there were Turkey Vultures circling above and a small group of Black Vultures in the trees; there was something dead in the swamp.

Four of the seven Black Vultures in the swamp between Catch the Wind and Explore the Wild.

Looking closer, I noticed one of the vultures next to a drain pipe which is close to the base of the dike that supports the trail. The bird was feeding on a carcass, a Raccoon.

A Black Vulture feeding on a Raccoon carcass (the animal's ribs are visible just in front of the bird's feet).

Turkey Vultures often find a carcass, but it’s the Black Vultures that usually finish off the animal. Turkey Vultures have a highly development olfactory nerve (they can smell well) and it’s usually the smell that draws them in to a dead animal; the Black Vultures follow them in.

Vultures usually hang out in groups in search of carrion and perch together in trees at a kill site or at their night-time roosts. One of the hazards inherent in these large birds traveling and roosting in groups can be seen in the image below.

Communal roosting has its hazards especially when you perch below a large bird like a vulture. The "whitewash" on this bird's feathers is excrement from a bird perched above it.

This was the same location that I had heard the raven calling from the day before. The raven that I saw had been harassing a Turkey Vulture. Was it a coincidence that I had seen the raven at this spot the day before, and that it had been chasing a vulture. Ravens eat carrion, are well know for scavenging whatever food they can find, and are often accused of being “mischievous.” I think it reasonable to suggest that the raven had been attracted to the activity around the raccoon, stopped in to investigate (or for a bite) and chased off a vulture or two when it left, just for spite. But I could be wrong.

]]> http://blogs.ncmls.org/greg-dodge/2009/12/18/the-raven-and-the-vultures/feed/ 0 http://blogs.ncmls.org/greg-dodge/2009/12/16/at-home-in-the-wetlands/ http://blogs.ncmls.org/greg-dodge/2009/12/16/at-home-in-the-wetlands/#comments Wed, 16 Dec 2009 15:01:23 +0000 Greg Dodge http://blogs.ncmls.org/greg-dodge/?p=3023 Two bird species that have become regular fixtures in the Wetlands, at least during the winter, are Red-shouldered Hawk and Hooded Merganser. Both species can be seen daily, or nearly so, depending on the weather conditions.

The Red-shouldered Hawk is present year-round and is the most common hawk species seen at the Museum, often hunting from a perch somewhere in the Wetlands or up in the swamp between Catch the Wind and Explore the Wild on the back side of the trail that winds through those areas. In winter, due in part to the lack of leaves on the trees, the hawk is a bit more obvious as it sits silently (most of the time these hawks are quite boisterous) in one of the Wetland’s Willows ready to pounce on any frog, small rodent, or bird that happens to make a false move.

Red-shouldered Hawk silently perched six feet above the waters of the Wetlands.

While I stood and watched the perched hawk (no more than 20 feet or so beyond the path) hoping to see it in action, a Red-tailed Hawk called loudly and persistently from above. Red-taileds are another hawk regularly seen during winter. Red-tails are larger that red-shouldereds. They are also typically much less vocal, and I thought it odd that this one was sounding off so with such gusto.

Red-tailed Hawk soaring above the Wetlands.

Apparently, the Red-shouldered Hawk thought the other hawk’s enthusiasm was odd as well as it seemed distracted by the Red-tailed Hawk, peering up at it as it circled above.

Red-shouldered Hawk hawking a very exciting Red-tailed Hawk circling above.

I never discovered why the Red-tailed Hawk was so excited, but I saw it (I assume it was the same bird) later that day circling above the Wetlands with another Red-tailed Hawk. It was a rather spring-like day and perhaps the hawk’s display was a premature (by a couple of months) attempt at courtship.

The Hooded Mergansers arrived on the scene the first week in November. Their numbers fluctuate between two and about a dozen, although I’ve seen as many as 15 in the Wetlands.

Hooded Mergansers taking up their old familiar resting and preening spot in the Wetlands.

When these ducks arrive they begin to form pair-bonds and can put on quite a show in their courtship displays. The males (from two to as many as six or more) follow the female around the water, strutting, pumping and chasing around, at the same time uttering a rolling, croaking sound as they vie for the female’s attention.

Four male Hooded Mergansers surround a lone female (dark object in center) as they vie for her attention.

Males strut their stuff while the female swims by.

The birds give a low-pitched croak-like call as they literally bend over backwards in an attempt to persuade the object of their attention, the female, that they are worthy.

The birds don’t actually mate at this time, but simply form the bonds that will hold them together until the breeding season arrives. The Copulatory Display (and actual mating), will probably take place in February or March just before these birds head back north, and is quite another show entirely. Oddly, considering the effort put into the pair-bonding, the male departs the nesting area after incubation begins, leaving the parenting duties to the female.

Red-tailed Hawks continue to be seen daily and Cooper’s Hawks have been noticed flying and perching in the vicinity of the previous year’s nest site. And, as mentioned above, Red-shouldered Hawks are once again showing up in the Wetlands.

Eastern Phoebes are calling regularly in and around the Wetlands. Phoebes nest on ledges. I’ve witnessed the birds investigating potential nest sites both under the boardwalk and in the vending area near the Red Wolf Enclosure. There are numerous crossbeams under the boardwalk for the phoebes to build a nest upon. The structure that houses the vending machines also offers many suitable ledges.

An American Crow was seen carrying nesting material on 1 March. Fish Crows had been seen (and heard) throughout the period.

The Brown-headed Nuthatches, which last month had so diligently excavated nest holes in a Loblolly Pine along the path between the entrances to Catch the Wind and Explore the Wild (see Brown-headed Nuthatches, Explore the Wild Journal, February 16-28, 2009), have apparently presented the holes to, or have been evicted by, a pair of Carolina Chickadees. In the images at left you can see a chickadee in the process of renovating one of the holes by first entering the hole, then exiting with a beak full of wood chips from the cavity’s interior.

During the first few days of this period, two Brown-headed Nuthatches were spotted working on a hole in a dead pine behind the vending area next to the Red Wolf Enclosure. They were not seen at that location during the second week of March. Are these the same two nuthatches that bored the holes for the chickadees? Have they abandoned this new hole too?

There have been numerous reports over the past several weeks of large numbers of American Robins throughout North Carolina; the robins are on the move north. So, it’s no surprise that hundreds of American Robins joined the already present, and equally numerous, Cedar Waxwings in an assault on the Museum’s hollies which began at the end of February (see Cedar Waxwings, Explore the Wild Journal, February 16-28, 2009). The birds were mainly concentrating on the hollies along the side entrance to the Museum’s main building, although few hollies anywhere on the grounds were immune to the onslaught (two trees out in front of the Museum seem to have been ably defended by a Northern Mockingbird, with most of its berries intact). Some of you may have noticed that all of the berries are missing from the small hollies behind the Ornithopter. The hollies in front of the Ornithopter were spared due to the human traffic through the area, the birds being reluctant to feed where people frequently pass. By the end of the first week in March, the waxwings had departed and only a handful of robins presently remain on site.

The first Red-winged Blackbird of the season appeared on the 7th of March. This lone male was seen and heard singing from a willow in the Wetlands.

Two Pine Siskins were observed at the Bird Feeder Exhibit during the period. Eight of those slender finches were seen in an elm tree behind the Sailboat Pond on the 3rd of March. It won’t be long before they leaves us.