Sunday, January 30, 2011

American Oystercatcher Odyssey

In one of my first blogs, I mentioned that I photographed a banded American Oystercatcher on Martha's Vinyard.  The date was 14 September 2009.  I finally have some data on this bird from the bander, Sean Murphy:

"this bird has quite a story.  

"P3 was banded as a chick in 2006 on a beach in Nantucket called Quaise.  Since then it was observed in VA for the 2007 winter.  Then, P3 disappeared for a year only to show up in August on Coatue, Nantucket, MA in 2008 (but not breeding ... yet).  P3 returned that fall to winter in VA.  In 2009, P3 jumped islands to West Tashmoo, Martha's Vineyard and found a nice stretch of beach to nest! Unfortunately, their  nest was unsuccessful.  Not too surprising for an oystercatcher trying to nest at 4 years old.  

"As a bird of patterns, P3 returned to the eastern shores of VA for the 2009/2010 winter and returned to State Beach in Oak Bluffs, [Martha's Vineyard] to nest with another banded oystercatcher, EH.  Strike two ... their 2010 nest attempts failed.  After that season, what else to do but return to the winter grounds...As of November 2010, P3 has been observed enjoying the life at its winter home in VA."

Friday, January 28, 2011

Eastern Cottontail

The Eastern Cottontail is one of the most common small mammals of Minnesota (Minnesota Department of Natural Resources), yet until last evening my only evidence of their feeding below our bird feeders was their tracks in the morning.  Despite very poor light, finally I was able to photograph one for my blog. 

Cottontails are prolific.  During the summer, they give birth to litters every three or four weeks. We would be knee-deep in rabbits were it not that cottontails serve as prey to a number of hunters, both human and many others, including hawks and owls.  Cottontails serve as reservoirs for Rocky Mountain Spotted Fever (transmitted via ticks) and, perhaps more importantly, tularemia.  This disease is caused by a bacterium and causes flu-like symptoms.  There is a five percent mortality rate for untreated cases--one percent for treated ones.  Although the bacterium is transmitted by ticks, horseflies or mosquitoes, it can also be transmitted by direct contact with uncooked rabbit meat (Google Health). Care is advised for anyone handling wild rabbits.

Tuesday, January 25, 2011

Wire-tailed Manakin

The photo above is of a male Wire-tailed Manakin from eastern Ecuador.  Male manakins form leks, where several males court.  The Wire-tailed Manakin makes perches from which they perform short flights and jump and fan their lower back feathers.  Other manakins make distinctive calls, clap their wings, and do somersaults at their leks.  Females come and mate with the sexiest males. The females then build the nests, incubate the eggs, and care for the young.  The males only contribution to raising the young is the males' courtship dance. Presumably their bright colors might attract predators.  Consequently, this is what female Wire-tailed Manakins look like:
During our expeditions to Ecuador and Peru, we were so busy with our research, we did not take many bird photos.  An exception is a series of bird photos we took with our friend James Yost.  Jim built a box out of blue parachute cloth.  We then placed previously netted birds in the box. You can see the blue cloth in the background of these photos.

Saturday, January 22, 2011

Royal Flycatcher

Erika and I missed most of the 1970s.  (It is a bit disconcerting that so did most everyone under 30 or so.)  In our case, we spent the decade pursuing our advanced degrees at Louisiana State University under George H. Lowery, Jr.  During the decade, we spent a total of 32 months in the Amazon jungles of Peru and Ecuador, recovering between expeditions by amassing graduate course credits.

This photo is of a Royal Flycatcher.  Not a whole lot is known about this bird.  Ornithologists argue about how many species of Royal Flycatchers exist--anywhere from one to five.  (If there is more than one species, then this bird is an Amazonian Royal Flycatcher.)  Scientists do agree that Royal Flycatchers are seldom seen and presumably rare or uncommon.  They are said to nest in swampy areas.  With 15 feet of rain a year, and no dry season, our study area in eastern Ecuador met that criterion. We encountered the species only a few times, and never except in our bird nets.  One problem is that they don't raise their crests unless they are feeling sexy or angry.  This one is pretty angry, since Erika is holding its feet.

Wednesday, January 19, 2011

Red-tailed Hawk

Several years ago, I took this first Red-tailed Hawk near Madison, South Dakota.  This species is common but variable across North America.  Except in extremely dark individuals, they can usually be identified by the dark necklace across their lower breasts.  I wrote a paper for South Dakota Bird Notes that gives an introduction to identifying Red-tailed Hawks.

I have had less success photographing Red-tailed Hawks in Minnesota.  Perhaps the problem is all of us Minnesotans in Minnesota that makes them relatively wary.  I found the photo below to be amusing: a Red-tail in dense forest at Nerstrand Big Woods State Park.  I do not often see Red-tailed Hawks in dense forest.  Usually this species inhabits open areas interspersed with forest patches.  (We Minnesotans, however, realize that Red-tailed Hawks also are often seen in urban Minneapolis/St. Paul.  The species also inhabits dense forests in Central America.)
The juvenile bird (note the lack of a red tail) was photographed on a cold, snowy January day.  Hunger may have driven it into the woodland.  Red-tails eat "a wide variety of small to medium-sized mammals, birds, reptiles, amphibians, arthropods, and fresh carrion" (Preston and Beane 2009). The eye gazing through the forest makes me realize that, even in the quiet depths of the forest, we are watched.

Sunday, January 16, 2011

Rough-legged Hawk

Rough-legged Hawks breed across the high arctic of both the Old and New Worlds.  North American birds mostly winter in the northern United States.  Their numbers tend to fluctuate from winter to winter, perhaps as a result of local rodent populations.  The species is a treat to see as individuals gracefully hover over snowy fields before plunging toward their prey.
Rough-legged Hawks, like this one photographed near Nerstrand Big Woods State Park (on 14 January), can be remarkably tame  (often to their detriment).  Because of its relatively small size, I believe this hawk is a male; its pale head indicates a young bird.  The dark vest and dark underwing spots at the wrists (not visible in this photograph) leave little doubt as to the hawk's identity.  (This photo was taken without the aid of lures--just dumb luck; the white backgrounds are due to cloudy skies.)

None of my field guides, however, illustrate Rough-legged Hawks with such bright rufous flank feathers or with such a white tail.  The photos of the perched bird only suggests its dark subterminal tail band.  In the flying bird, the band is hardly visible.  Is this a case of partial albinism (leucism)? Rough-legged Hawks are famously variably plumaged, and range from being almost completely dark to very pale. Look at the legs of this hawk.  Above their bare, yellow toes, the legs are clearly feathered.  This feathering is why the hawk is called rough-legged.

Friday, January 14, 2011

Northern Fulmar

The Northern Fulmar is another tube-nosed seabird that I added to my list off the Washington coast in 2001. The tubular nostrils are present in many seabirds that drink salt water.  These structures function for salt excretion (Handbook of Bird Biology).

Fulmars are abundant over the North Pacific and Atlantic oceans.  Fulmars in the Pacific Ocean are usually dark, but in the Atlantic they come in white and dark phases and everything in between.  Nobody knows the function of these color phases.  The phases mate indiscriminately. 

Fulmars are reproductively odd.  They live over 40 years, and often do not mate for the first time until they are at least eight years old.  Pairs only produce one egg per year.  Nevertheless, Fulmar numbers in the North Atlantic have spectacularly increased during the last 250 years.

Fulmars are nocturnal foragers, consuming a wide variety of sea life.  Like the albatross, they have an acute sense of smell.  On my pelagic trip off Westport, Washington, only one cup of cod liver oil off the side of the boat attracted a hoard of fulmars--even in daytime.  Much of the information in this post is from Hatch and Nettleship (1998).

Wednesday, January 12, 2011

Snowy Owl

On Tuesday afternoon, Gene B. called to report a Snowy Owl in Rice Co. near the intersection of MN 19 and Dakota Co. 59, just within Rice Co.  I raced over to find the bird perched on a tall metal grain bin. Due to its extensive barring, this bird is probably a female.  The owl was being harassed by a small flock of Snow Buntings (as you can see in the upper left corner of the photo).
With the buntings gone, the owl preened and scratched, occasionally checking for additional bunting attacks.  Snowy Owls are birds dependent on Arctic lemming populations.  When lemming populations crash, the following winter Snowy Owls make their way south.  I have read that, if Snowy Owls do not see lemmings in the spring, the owls do not ovulate.  The next year lemmings begin to recover, as do the owls. When lemmings are abundant in the arctic, these owls consume nearly 2000 per year.
Snowy Owls are adapted for cold weather.  Tuesday's 25 degrees F. must have been a heat wave for a Snowy Owl.  I have never seen this posture.  I suspect the owl was trying to "unbutton" its down coat to cool off during this relatively warm day!

Monday, January 10, 2011

Common Goldeneye

Erika and I drove to Prescott, Wisconsin in hopes of finding a Barrow's Goldeneye.  This species is a western bird that is occasionally seen in Minnesota.  Among males, two field marks usually stand out.  The Barrow's Goldeneye has darker sides than do American Goldeneye (the duck expected in midwinter Minnesota).  I was excited to see a couple of dark-sided goldeneyes.  But these birds both lacked the second field mark--Barrow's Goldeneyes have crescent-shaped, not roundish, face spots.  Check out the crescent-shaped face spot on the Barrow's Goldeneye in the last photograph on this post--a bird from Rapid City, South Dakota.  I decided that these dark-sided Prescott birds are first-year winter male American Goldleneyes.
A third field mark is that the Barrow's Goldeneye's bill is shorter than the bill of the American Goldeneye.  I think the difference in bill shape is fairly clear in these two photographs.  Female goldeneyes are generally harder to identify.  Note the female American Goldeneye in the middle of the flock above.  Its bill is yellow-tipped.  The female Barrow's Goldeneye's bill is most often almost all yellow.

Saturday, January 8, 2011

Slaty-backed Gull?

I do not consider myself a gull expert.  I find them quite difficult to identify.  On our return from Prescott, Wisconsin, Erika and I stopped at the Number Two Lock along the Mississippi River in  Hastings, Minnesota. This photo was taken during a blizzard, so it is not optimal. The black line through the eye, the very dusky sides of the head and neck, the broad, white window at the wings, the relatively dark back, and the very pink legs all are field marks of the Slaty-backed Gull.  Note the yellow eye.  The red spot on the bill also seems to be the shape seen on some Slaty-backed Gulls. Compare the dark back to that of a nearby Herring Gull (second photo).
Since Slaty-backed Gulls began breeding in Alaska a few years ago, they have been reported with increasing frequency in the Upper Midwest.  Postscript: further study and input from readers suggest this may be a Vega Gull, a race of the Herring Gull normally found in the Bering Sea.  Herring Gulls, however, are notoriously variable in plumage.

Friday, January 7, 2011

Black-footed Albatross

It is hard to believe that 9/11 was ten years ago and that this photo was taken on 8/13/2001, only a month before the world changed.  I attended the American Ornithologists' Union's annual meeting in Seattle.  One advantage to a congress of birders is that their pre-meeting field trips are often fruitful.  I signed up for a pelagic trip out of Westport, Washington.  They took us 60 miles out into the Pacific Ocean.  You might think that no birds would inhabit the open ocean, but it was a bird bonanza.  I added a half-dozen species of my life-list. Included among the new species were many Black-footed Albatross. 

Tube-nosed seabirds, an order that includes the albatrosses, shearwaters, fulmar, and various petrels, are odd among birds in that they have tubular nostrils and an extraordinary sense of smell.  They use this ability to smell to find both their prey and also their breeding grounds.  Their sense of smell is so acute that our guides had but to toss a cup full of cod-liver oil into the sea before our small boat was surrounded by seabirds.

The Black-footed Albatross breeds on the Hawaiian Islands and ranges across the North Pacific. The species feeds on squid and flying fish eggs.  It also follows ships, picking up whatever the fishermen throw away.  Unfortunately, it also eats plastic trash floating on the sea.  Fishing nets and longlines also contribute to this albatross' decline (Awkerman et al. 2008).

Wednesday, January 5, 2011

Downy Woodpecker 2

The winter birds at our feeder are not diverse.  I think the problem is that the small woodland that comprises our back yard lacks much brushy cover.  Thus I am content to feed a small number of Downy Woodpeckers and Black-capped Chickadees.  Other species make sporadic visits.  I have marveled at the beauty of female Downy Woodpecker napes.  Males sport a gaudy red nape patch, but to me the pattern on female's nape is simply stunning.

Monday, January 3, 2011

Downy Woodpecker 1

Last Sunday, Erika and I birded the River Bend Nature Center in Faribault, Minnesota. Returning home, I was surprised by this Downy Woodpecker's dull eye.  I enlarged the the photo below and discovered that I had captured the bird's nictitating membrane in action.
All birds have nictitating membranes, third eyelids that blink sideways across their eyes.  The membrane is transparent and moistens the cornea.  This Downy's nictitating membrane appears to be fairly opaque, which would be a pathological condition.  I researched the Internet and discovered that the membranes also protect birds' eyes much as do aviators' or divers' goggles.  Woodpeckers, indeed, have relatively thick nictitating membranes to protect their eyes from flying wood chips (Bay Nature Institute).  Wikipedia further claims "Woodpeckers tighten their nictitating membrane a millisecond prior to their beak impacting the trunk of a tree in order to prevent their eyes from leaving their sockets."

I was delighted that this woodpecker posed in front of a snow bank--thus, the white background.  Elsewhere in this blog (5 March 1010) I discussed identification tips for Downy Woodpeckers.

Saturday, January 1, 2011

New Year, New List

The New Year inspires enthusiasm to renew my various birding lists.  This year I plan to keep a running tally of my 2011 list on a tab above my blog entries.  You are welcome to visit this list.  My modest goal is to break 300.

I am not a twitcher--I seldom chase after rare birds--at least not until a week after they disappear.  I much prefer the birds to come to me. I do keep lists: life list, year list, and Minnesota county lists. My Minnesota list stands at 264, but in any given year I tally around 200.  My Rice Co. list sports 230 species.  Annual Rice County lists range from 177 to 183.  None of my other country lists exceed 100, perhaps due to my disinclination to go chasing, or perhaps my banding ties me to my home county. 

My annual list size depends on where we have traveled.  Since 2007, my annual totals have been 206, 326, 221, and 241. The 326 resulted from a 2008 winter jaunt to California, the southwest, and Texas.  I keep all my lists on Excel files; the publication on the left might be of interest to those wishing to keep their lists in a convenient book.