Sunday, September 30, 2012

Le Conte's Sparrow

Le Conte's Sparrows were reported from our area on eBird this past week. Erika and I searched for them, but were not too surprised not to find one. These sparrows are infamous for being uncooperative. They only reluctantly flush from their grassland habitat and prefer "creeping about like mice under mats of grass" (Lowther 2005). The same author reports that one Wisconsin researcher "found only 8 of 86 singing males on perches exposed enough to provide an identifiable view." I took this photograph several years ago near Brookings, South Dakota.

This sparrow was named for John L. Le Conte, a friend of Audubon and a distinguished physician, physicist, chemist, teacher, and naturalist. He was president of the University of California, Berkeley, from 1875 to 1881 (Gruson 1972).

Friday, September 28, 2012

Lapland Longspur

This blog is a cautionary tale about bird photos. Leaving Hawk Ridge last Sunday, Gerry Hoekstra and I discovered a cooperative Lapland Longspur at Park Point, Duluth. We took the first two photographs at the same time and of the same individual bird--the first photo was taken by Gerry, the second is mine. We use different cameras, lenses, and camera settings. We also manipulate our photos differently with different software. I tend to overwork my photos a bit. The casual observer would hardly recognize these two birds as the same species, much less the same individual. This variation is one reason I am not a big fan of identification books containing photos rather than painted portraits.
The second set of photos also show the differences in our work. The third photo is by Gerry, and fourth is by me. I am not sure about the "reality" of these photos--I do not remember which of our photos is a more accurate longpsur representation. I have previously blogged on Lapland Longspurs. This bird was one of a flock of about 20 in the grass at the picnic area near the airport at Park Point.

Thursday, September 27, 2012

Duluth Sparrows

One of the highlights of our Hawk Ridge visit on Sunday was the plethora of sparrows drawn in by seed spread out near a set of passerine banding nets. Despite intrusions by clueless tourists and unthoughtful volunteers, the birds were relatively tame and easy to photograph.

The first photo is of the the eastern Zonotrichia leucophrys leucophrys. Note the black line the links the eye to the bill. The lores are white or pale in western races. The orange bill indicates this individual is a northern, rather than eastern, bird. Birds from further east have pinkish bills. I posted accounts of western birds on 17 November 2009  and 21 September 2012.

The second bird is a bright White-throated Sparrow. As I have previously posted, White-throats come in bright and dull color morphs. This variation has nothing to do with the bird's sex and is poorly understood. The third photo is of a dull morph bird.

Finally, one Fox Sparrow visited the feeding area. I have recently written about the variation and systematics of this species. The name Fox derives from the rufous rump and tail feathers.

Wednesday, September 26, 2012

Krider's Red-tailed Hawk

Probably the highlight of our Hawk Ridge visit last Sunday was the capture of this very pale Red-tailed Hawk. Chances are that this bird is a Krider's Hawk. Krider's Hawks are perplexing. Apparently they are a pale morph of Red-tailed Hawk that breeds in the Dakotas and Montana. The normal breeding bird in the upper midwest is the western race of the Red-tailed Hawk, which come in three color morphs: dark, intermediate, and light. Krider's Hawks are even paler than light Western Red-tails. Possibly Krider's Hawks are a fourth morph of Red-tailed Hawk arising from birds intermediate between Western and Eastern Red-tailed Hawk races. Whatever a Krider’s Hawk actually is, extreme caution should be used differentiating pale and very pale morphs of Red-tailed Hawks.

Tuesday, September 25, 2012

Hawk Ridge

Hawk Ridge Sanctuary, run by a nonprofit organization, sits atop a rise above Duluth, Minnesota. Because hot air thermals do not form over water, migrating hawks tend to fly around large bodies of water, such as Lake Superior.  Hawk Ridge provides some of the most spectacular hawk-watching opportunities in North America, with an average of nearly 95,000 raptors passing overhead from October through November (MOU). Erika and I, along with our friends Gerry and Merry H., paid Hawk Ridge a visit last Sunday.
We enjoyed our visit, despite large crowds of visitors and relatively few hawks. Only about 500 were counted on Sunday (and we saw only a fraction of that number). Most of these raptors, like this juvenal Broad-winged Hawk, flew at such heights that they were often visible only as pin-spots, requiring scopes or binoculars to see, much less to identify them. Many of the hawks are identified only by body silhouette.  Our hawk lacked the broad white tail bands of an adult, but can be told by the general body shape and by the relatively broad dark band at the end of the tail.
Hawk Ridge bands both raptors and passerines. Trained volunteers run these programs. While we watched, they banded a half-dozen Sharp-shinned Hawks (see photo above) and a couple of Red-tailed Hawks. The crowds of people were well entertained and educated by these activities. The volunteers allowed people to "adopt a raptor," by paying $25 and releasing the banded birds. I will write more about Hawk Ridge over the next week of blog posts.

Monday, September 24, 2012

Oregon Junco

Dark-eyed Juncos breed in forests across Canada and the northern United States south into the Rocky and Appalachian mountains. Juncos winter across the midwestern and southern United States to northern Mexico. The species is abundant, with estimates of the total population thought to be 630 million individuals (Nolan et al. 2002).

With so many birds breeding over such a wide range, junco populations exhibit a great deal of variation. The result has been labeled a "turbulent taxonomic history" and a "nightmare for systematists" (Nolan et al. 2002). Until the 1970s, juncos were split into five species and a number of races. The American Ornithologists' Union currently lumps these species into one, the Dark-eyed Junco, with 15 races assigned to five "groups."

The photograph above is of a Dark-eyed Junco of the "Oregon" group from our travels to Olympia, Washington, last April. Note the angle of the white belly where it meets with the black breast and pink sides. This angle is sharp, not rounded. Oregon Juncos are sometimes reported in winter from Minnesota, but care must be used to eliminate the possibility of Junco hyemalis cismontanus, a brownish race of the "Slate-colored" Junco group, which often winter in Minnesota.

Saturday, September 22, 2012

Golden-crowned Sparrow

Another common bird in our son's bird feeder last April in Washington was the Golden-crowned Sparrow. This species is a common winter bird in shrubby and urban areas along the West Coast of the United States, but it breeds further north in British Columbia and Alaska. Relatively few behavioral studies have been conducted on this sparrow. Norment et al. (1998) write that Alaskan goldminers called this bird "Weary Willie "because it was forever singing 'I'm so tired!'...Others called it the 'No Gold Here' bird," again interpreting the call (link curtesy Thayer Birding Software.)

Friday, September 21, 2012

White-crowned Sparrow

We arrived in Olympia, Washington, last April, our granddaughter having the courtesy to wait to be born until after we listed our first-ever Rock Sandpiper. We spent the next week tending to children and a newborn, and thus had little time for birding. Our son keeps a feeder, and I was able to take photos of a few interesting birds.

White-crowned Sparrows are common in Olympia and their distinctive calls can even be heard in downtown areas of the city. (The call file is courtesy of Thayer Birding Software.) Some time ago I wrote about the four races of White-crowned Sparrow. Because we were on Puget Sound, it stands to reason this bird is Zonotricha leucophrys pugetensis (a race unlikely to be encountered in Minnesota). Confirming field-marks include the white lores and yellow (rather than orange) bill.

Wednesday, September 19, 2012

Rock Sandpiper

Erika and I gave the Rock Sandpiper one more try. We drove around Gray's Harbor and checked out the north jetty at Ocean Shores, Washington. As you can see in these photos, we found our nemesis bird. One reason this species can be hard to list is that it is a late fall (October-November) and early spring (April) migrant, thus a relatively small window in time exists in the winter range to see this rock-loving sandpiper. Further, they return to specific wintering areas. Thus knowing about the north jetty at Gray's Pass may be critical to easily find them. We found them feeding among the rocks, dropping down as waves receded, only to pop back to rock-tops as the next waves crashed into the rocks.

Reading about Rock Sandpipers in Gill et al. (2002), I learned a new word, pagophilic, which means ice-loving. Perhaps because these birds winter further north than other North American shorebird, they often roost on sheets of ice. I also learned that Rock Sandpipers, during migration, can be found on muddy or sandy tidal flats away from rocks. Rocky and/or man-made substrates, however, are the rule in their winter range from coastal southern Alaska to northern California.

Tuesday, September 18, 2012

Semipalmated Plover

Another common shorebird Erika and I saw last April at the south jetty of Gray's Pass in Washington was this Semipalmated Plover. This plover breeds in Alaska and arctic Canada. The species winters along the coasts of North, Central, and South America. This species is one of the few plovers enjoying increasing numbers--it is not very particular about its food choices and its wide range protects it from local catastrophes (Nol and Blanken 1999). Spring Semipalmated Plovers, like the spring South Dakota bird below, show a black breast band. The Washington bird is in basic (winter) plumage.

Monday, September 17, 2012

Red-headed Woodpecker


I have previously posted photos of adult Red-headed Woodpeckers on this blog. A good place to find this striking woodpecker is Nerstrand Big Woods State Park near Northfield. I have never, however, seen this bird at my banding station in Northfield and nor have I banded one during my career as a bander. I hardly recognized this juvenal Red-headed Woodpecker--no red head! The bright white wing patches, however, were a significant field mark. If you you closely at these photographs, you will notice a single red feather in the woodpecker's crown.

According to Smith et al. (2000), surprisingly few intensive studies exist of this conspicuous, if relatively uncommon, woodpecker. Few banding studies have been attempted. Do the sexes differ ecologically? No data on growth or development of the young have been gathered. The role of the European Starling in the decline of the Red-headed Woodpecker has not been proven and may not be true. Smith and her coauthors conclude "certainly this species' habit of nesting in dead branches in precarious places has hindered breeding studies..."

Sunday, September 16, 2012

Western Sandpiper

Also at the south jetty at Gray's Pass last April, Erika and I photographed this sandpiper. The bird in the photo appears to have an odd, square-shaped head. I am not sure what to make of that apparent abnormality. Because of the broad black spots and slight reddish edges on the scapulars, the relatively long bill (for a small sandpiper), and the black legs all lead me to identify this bird as a Western Sandpiper. Plus Western Sandpipers are "one  of the commonest shorebirds of the Western Hemisphere, wintering along the Pacific coast of North America and the south Atlantic coast" (Wilson 1994).

Saturday, September 15, 2012

Dunlin and Sanderling

After discovering from eBird that Rock Sandpipers were still being seen on the pier jettys on either side of Gray's Pass, Washington, Erika and I made one last attempt to list this nemesis bird.  We actually made two attempts, as we first visited the south jetty, and, striking out, drove around Gray's Bay and searched the north jetty too.

On the south jetty, we tried to make a Surfbird into a Rock Sandpiper, but to no avail. We did, however, see a number of other shorebirds in the area. The flock photographed above is of a flock of sleeping sandpipers. The two slightly smaller, pale birds are Sanderlings. The remaining dozen birds would be difficult to identify were it not for the one bird with a black belly--a sure sign of a Dunlin.  In the spring Dunlin are not difficult, as you can see in the lower photo taken in the spring in northeastern South Dakota--black bellies, long, somewhat drooped bills, and reddish backs. Our Washington birds were, with the one exception, in basic, winter plumage.

I have previously posted on the Sanderling. The Dunlin is a common breeder across the Arctic regions of North America. In winter, look for Dunlin along the coasts of the United States and northern Mexico. The species is abundant. Some Alaskan breeders winter in eastern Asia. Migrants are likely to be found almost anywhere in the US. About a half million Dunlin winter on the Pacific Coast. Mortality in this population is in large part due to predation by raptors (falcons and hawks) (Warnock and Gill 1996).

Thursday, September 13, 2012

Vireos

As many of you are aware, after taking a photograph of a hand-held bird in front of a snow drift one winter, I became fascinated by bird portraits with white backgrounds. The results of this photography can be seen in my Picasaweb White Album. The two photographs in this post are from this year. I banded the Warbling Vireo this spring. Note the pale sides to its face and lack of any dark eye line. Previously I have posted on telling Warbling and Philadelphia vireos apart. The Blue-headed Vireo below was banded last week. I have also previously posted about these sporty, easy to identify birds.

Buoyed by the positive reception of my recent dragonfly book, I find myself embarked upon producing a non-digital White Album, a large-format text. I have the photographs paginated, but don't hold your breaths.  I have written none of the accompanying text, a chore that should take me many a happy winter month.

Tuesday, September 11, 2012

Astoria Ducks

I mentioned in my last post that waterfowl were easily photographed along the Astoria, Oregon, Riverwalk. Two of these ducks were the Bufflehead above and the American Wigeon below. I have previously blogged on both species (see the bufflehead posts here and here and the wigeon post here). I will limit my discussion here to the different types of ducks.  Most ducks are either diving ducks or dabbling ducks. The divers, like the Bufflehead, normally dive for their good, whereas the dabblers eat off the surface or submerge their heads, while their tails bob above the water surface. Dabbling ducks can walk on land, but the divers have their feed so far back that they have a tough time on dry land. Finally, diving ducks have to run across the water to achieve airspeed; dabblers can take to the air in a single leap. Other, smaller groups of waterfowl include the geese, swans, stiff-tailed ducks (like the Ruddy Duck), and whistling-ducks.

Monday, September 10, 2012

Peregrine Falcon

On our travels, we seldom stop in inner cities, as they are not likely to offer much for birding. Astoria, Oregon, proved to be an exception. The city built a five-mile riverwalk along the Columbia River. Alongside the walk is a trolly line, which tired hikers can ride back to their hotels. The riverwalk skirts a rather rundown, but still active, industrial dock area, with large buildings, ruined docks, abandoned piers and rusted machinery (Family.go.com). Despite this rather dismal description, our walk yielded close views of a variety of waterfowl. Imagine our surprise when a Peregrine Falcon circled and landed on an overhead telephone wire. The photo above was taken just as the falcon was about to perch on the wire.

This raptor is "One of the most widely distributed of warm-blooded terrestrial vertebrates, the Peregrine Falcon occurs from the tundra to the Tropics, from wetlands to deserts, from maritime islands to continental forests, and from featureless plains to mountain crags—it is absent as a breeder only from the Amazon Basin, the Sahara Desert, most of the steppes of central and eastern Asia, and Antarctica" (White et al. 2002). Yet, by 1970, the Peregrine Falcon no longer bred across most of eastern North America and parts of Europe. Numbers were greatly reduced in many other areas. DDT and similar chemicals seem to be the cause of this calamity. Peregrines are recovering where these pollutants are now banned. As most Minnesotans are aware, active programs of introducing breeding falcons to cities, whose large buildings substitute for natural cliffs, also contribute to this falcon's comeback. Cities like Astoria and Minneapolis/St. Paul are now part of this magnificent falcon's habitat.

Saturday, September 8, 2012

Black vs. American Oystercatcher

Oswald West State Park is a small but remarkably beautiful Oregon State Park located south of Cannon Beach. Trails lead from a rest area on US Highway 101 to a sandy cove surrounded by forested hills. A freshwater stream flows from the forest into the sea. In the stream on the beach, we photographed a Black Oystercatcher. We later learned that Black Oystercatchers search for and bathe in freshwater streams.

You would not guess that telling a Black from an American oystercatcher presents much of a problem. Black Oystercatchers are found along the Pacific Coast, from the Aleutians to Baja California. The American is found along the East Coast, south through South America. The photo below is of a bird we saw earlier during our March road-trip along the Texas coast. Where their ranges overlap, in Baja California, the two species hybridize. Hybrids look like Black Oystercatchers with varying amounts of white. If the two populations hybridize, why aren't they considered one, variable species? Apparently the birds prefer to mate with similar looking birds. This preference breaks down only when population numbers are low and mates of the proper type can not be found (Andres and Falxa 1995).

Friday, September 7, 2012

Gray-cheeked vs. Swainson's Thrush

During the first week of September, several thrushes appeared at my banding nets. Usually identification of Gray-cheeked and Swainson's thrushes is not too difficult. The Gray-cheeked Thrush has gray lores and often has little or no white around the eye. The upper breast of the Gray-cheek is often white--the pale buffy wash in the upper photo is a bit unusual. The Swainson's Thrush, on the other hand, usually sports a bright buffy eye ring and fairly bright buff around the head and upper breast.

Gray-cheeked Thrushes breed in northern Canada, Alaska, and even Siberia as the forest gives way to tundra. These birds prefer thickets and stunted spruces with dense undergrowth. Swainson's Thrushes breed further south across Canada and Alaska, south into the Rocky Mountains (all the way to New Mexico) and northern New England. They are found in coniferous forests.

Where their ranges overlap, these two thrushes may hybridize (Mack and Wong 2000), which can complicate identification. Gray-cheeks can show quite a bit of white around their eyes. The white can look buffy in difficult light. The buff on a Swainson's can be difficult to see in poor light. Some races of Swainson's Thrush are quite gray, while others are remarkably rufous. Hybrids, if they actaully exist, only further complicate identification. My understanding is that a hybrids are hypothetical. Discovering a hybrid for sure will take a graduate student immune to blackflies.

Wednesday, September 5, 2012

Dusky vs. Red Fox Sparrow

Fox Sparrows are complicated. Sibley suggests that ornithologists will eventually recognize four species of Fox Sparrows: Red, Slate-colored, Thick-billed, and Sooty. These populations show differences in plumage, calls, songs, and DNA. See Birdfellow.com for photos. The trouble is that these populations apparently interbreed where they overlap. The group is also amazingly complex--at least 18 races are named that fall into one or another of these four "species" groups.

I have photos of two of these potential species. One, the Red Fox Sparrow, is a common migrant across Minnesota. The photo above is of one of my banded birds near Northfield. Erika and I found the Sooty Fox Sparrow, below, during our March travels up the Pacific Coast, near Newport, Oregon. Note that this bird allowed us close approach, perhaps due to a swollen tick under its apparently blind eye. The tips to its wing coverts suggest this bird is in its second year.

Tuesday, September 4, 2012

Red Phalarope

Again on the trail of Rock Sandpipers, the rocky jetty off the Yaquina Bay State Recreation Site in Newport, Oregon, offered great possibilities. Despite a several hour search on morning last March, we did not see a Rock Sandpiper. But our efforts were rewarded by several interesting birds.  Even from the bluffs overlooking the site, we saw several phalaropes twirling and feeding in wetlands near the shore. After some searching, we found a trail to the beach.

Because Red Phalaropes are "entirely pelagic" (meaning ocean-going) during migration and winter (Tracy et al. 2002), I assumed the first photo was of a Red-necked Phalarope. But closer examination reveals a plain, unstreaked gray back and a short, relatively thick bill with a yellow base--all field marks of a winter (basic) plumage Red Phalarope.  The other two species of North American phalaropes are in the photo below (taken at a lake near Pierre, South Dakota). The bird in front is a Wilson's Phalarope, the bird behind, a Red-necked Phalarope. Both are females in breeding plumage. In all three phalarope species, the females are brighter than the males. All three reverse the normal roles of the sexes, with males incubating and caring for the young. Females may even be polyandrous (have more than one mate). Note that, unlike the Red Phalarope, the phalarope species below have thin, needle-like bills that are completely black.

Monday, September 3, 2012

Scarlet Tanager

Scarlet Tanagers have an interesting molt sequence. The bird in this photo was banded in Northfield on Saturday, 2 September 2012. The unwary might identify it as a female. In fact, this tanager is a first-year male. The key is the jet-black wing coverts. Juvenal male and female Scarlet tanagers are probably inseparable. In their first fall, as the juvenal males molt in their first basic (winter) plumage, their grayish-brown coverts are replaced by jet-black feathers. But their brownish-gray juvenal flight feathers are retained. The following spring, the males become orange-red to scarlet. The next fall, the male again becomes greenish-yellow, but, this time, the wings and the coverts remain black. Thus you can identify first-year fall and winter males from ones in their second-year (and beyond).

Sunday, September 2, 2012

Coast Redwoods

Last March, rain in northern California resulted in poor birding and photography. But even the moisture could not distract, and may have even enhanced, the grandeur of the Coast Redwoods. Erika and I were driving up California Highway 101, when we chanced upon a sign proclaiming, "Scenic Road." Our gps assured us easy re-access to the highway. We found ourselves in the Humboldt Redwoods State Park.

According to the park website, Coast Redwoods are both the tallest and the among the oldest trees. They average several hundred years in age and are up to 370 feet tall, with diameters up to 15 feet. They can live more than 2000 years. The last ice age limited Coast Redwoods to a narrow, 450-mile strip along the Pacific Ocean from central California to southern Oregon. Fossil redwoods have been discovered across the western United States and Canada, and on the coasts of Europe and Asia.

Saturday, September 1, 2012

American White Pelican

Yesterday, 31 August 2012, Erika and I looked up as we finished biking on the Cannon Valley Bike Trail at its terminus just north of Red Wing, Minnesota. A huge flock of what we estimate to be 400 American White Pelicans circled overhead. Try counting the individuals in the top photo--I come up with a different number every time I try. Imagine trying to count as the birds passed overhead. Only about a quarter of the total flock is captured in the first photo. Because White pelican flocks usually number only up to 180 individuals (Knopf et al. 2004), we may have seen four flocks intermingling.

The world population of American White Pelicans, which breed across the Canadian and American prairies, was reported by del Hoyo et al. (1992) to be at least 104,000 in 1979-1981. Since then, numbers have increased by at least 3% a year. Early lower numbers were the result of draining of prairie lands, human disturbance and agricultural contamination (Knopf et al. 2004). In any event, these pelicans seldom migrate at night, preferring to catch thermals of warm air high into the sky, and then saving energy by gliding south to the next thermal. The birds we saw will probably winter somewhere along the Gulf Coast. Birds breednig west of the Rocky Mountains winter in California or along western Mexico and Central America.

These pelicans reminded me of a huge flock of White Storks that I photographed in late August 1963 near Tarifa, Spain. Here again the birds were taking advantage of rising thermals of air. Because thermals do not form over water, these storks take advantage of the thermals over land. Thus these storks save up to 23 times of their energy resources by gliding, rather than flapping to Africa across the Strait of Gibraltar to Africa (Wikipedia)