Wednesday, April 30, 2014

Familiar Bluet 2

We came up empty-listed in our Hook-billed Kite search in the Mission Nature and Bike Park. We did find, however, a couple of dragonflies. We found a lovely, female Red Saddlebags, I photo I will share with you in an upcoming post. Meanwhile we came upon this Familiar Bluet.

You may recall that I posted about this species from South Padre Island. This photo shows a couple of field marks fairly well.  The terminal appendages are almost as long as the last abdominal segment. The abdomen is also predominantly blue, with all but the last couple of black areas being small and similarly sized. Finally, the first black abdominal spot nearest the thorax touches the rear of segment two.

Tuesday, April 29, 2014

Cactus Wren

Erika and I spent three days in the vicinity of Mission, and exploring south Texas. The Rio Grande Valley is a birder’s paradise. Even the common birds can be new for us northerners and quite rare species are often encountered.

We devoted our first day, 21 February 2014, to visiting good friends who live on a ranch north of Edinburg. First, however, we stopped at the Mission Nature Park and Bike Trail. I was aware, after consulting eBird and watching the Texas Bird Listserv, that Hook-billed Kites had been seen at this park, only a mile from our hotel. We did not see the kite, but we were greeted by this raucous Cactus Wren.

As I wrote in 2011, Cactus Wrens are adapted for desert life. Water is not critical for this species—it can obtain the water it requires from food like cactus fruit. In the summer it reduces adreno-corticosterioids, and is thereby able to better withstand heat stress. Cold may be a critical factor for these wrens—below average temperatures can cause breeding failure (Hamilton et al. 2011). The species is found across the American southwest into central Mexico.

Monday, April 28, 2014

Familiar Bluet 1

As we the South Padre Island Birding and Nature Center on 20 February 2014, Erika suddenly let out a whoop: “Odonate Alert!” Our first dragonflies of 2014, or, in this case, damselflies, flew about in good numbers below our marshland boardwalk. I knew that few odonates inhabit brackish habitats—brackish being a mixture of fresh and sea water. I took out my iPad and, in my copy of the Paulson dragonfly guide, searched for the word brackish. Since most odonates inhabit freshwater areas, I had limited choices for those in brackish areas.

One species that fits the habitat is the Familiar Bluet. The largely blue middle abdomen segments distinguish the male from other bluets. The females are similar to other bluets and are best identified by whom they are attached. The species is abundant across much of the United States

I have previously written about the fascinating world of dragonfly sex, wherein males and females form wheels, with the male guarding the female from competing males while she takes semen from his thorax. Familiar bluets often remain attached as they fly about, sometimes for over 30 minutes. He lets go when the female oviposts, after which she often rejects second couplings by him or one of the other males. Other times, however, the first pair again flies in tandem.

Sunday, April 27, 2014

Waterfowl

On 20 February 2014, the South Padre Island Birding and Nature Center hosted numerous waterfowl. In this photo, a White Ibis stands next to a Green-winged Teal. Two hen American Wigeon preen with a Blue-winged Teal between them. Three Redheads swim in the right foreground.

The White Ibis seldom ventures out of the Deep South. I will write more on this species in a subsequent post. The ducks, however, will migrate north and likely breed in the prairie pothole region of the upper Midwest and the Canadian provinces. Only with aggressive management are their numbers maintained in the face of wetland draining, tiling, and destruction.

Saturday, April 26, 2014

American Coot

American Coots are abundant across most of North America and are found into northern South America. I have previously blogged on the species. Note the individually webbed toes in the coot in the second photo. Because these toes are not webbed together allies the coots to rails rather than to ducks. Ornithologists hypothesize that coots originated from gallinules and are specialized for diving.

Although I have never tasted a coot, the species is considered to be a game species. I saw a recipe for coot with strawberries and cream—the joke ends by suggesting anything tastes good with this sauce. In any case, an average of 888,000 coots have been harvested in Canada and the United States in the past 40 years. Coot populations, despite hunting and loss of wetland habitat, have increased since the 1950s. Coots readily take advantage of wetland restoration projects. In some urban areas in the winter, coots are considered to be pests, much like feral Canada Geese (Handbook of the Birds of the World—Alive).

These photos are both from our February 2014 Texas travels. The first is near Dallas, the second from South Padre Island.

Friday, April 25, 2014

Black-necked Stilt

A small flock of Black-necked Stilts flew out of the marsh on 20 February 2014 at the South Padre Island Birding and Nature Center. Stilts prefer wetlands with more vegetation than do avocets, though the two species are often found in man-made ponds. When breeding, stilts are less gregarious than avocets and often show more territorial behavior (Robinson et al. 1999). Silt numbers must fluctuate, since we saw far more stilts during our last visit to south Texas a few years ago. I suspect the availability of ponds must be a determining factor. This year was the fourth of relatively severe drought.

Thursday, April 24, 2014

Shorebirds

Last winter my dragonfly-guru, Scott King, read The Shorebirds of North America. In exchange for my showing him a yellowlegs, he promised me several odonates lacking on my list. I assured him that my part of this bargain this spring would not be challenging. On Tuesday, Scott and I easily found both species of yellowlegs, Greater and Lesser—the photograph above is of the Lesser. Note the short, needlelike, black bill.
Other shorebirds at the Randolph Industrial Park in Dakota County, Minnesota, proved a bit trickier to identify. I was not expecting these Dunlin to be in such drab basic plumage. Our first clue in the bird above was its relatively long, down-curved bill. In the subsequent two photos, note the black belly speckles and occasional reddish back feathers.
Dunlin winter on the coasts of North America, from Alaska and Maine south to central Mexico. They breed in the high Arctic. Other Dunlin breed across Arctic shores of the Old World and winter in more southern latitudes of that hemisphere.
The Dunlin were outnumbered by Pectoral Sandpipers (in the foreground of the third photo and landing in the last one). Note the dark, sharply defined breast streaking and the dark line through the tail feathers. These shorebirds breed in the high Arctic, both in northwest North America and northeast Siberia. North American and most Siberian birds winter from Peru to southern-most Argentina. A few Pectoral Sandpipers winter across the Old World, across the Pacific Ocean, Asia and Australia, Europe, and Africa. The hypothesis is that this sandpiper originated in the New World, and spread into the Old. Most Asian birds return to their ancestral wintering range in South America (Farmer et al 2013).

Wednesday, April 23, 2014

Yellow-rumped Warbler

Another spring arrival at our water feature was this male Yellow-rumped Warbler. I previously wrote about how western (Audubon’s) and eastern (Myrtle) populations differ. Spring males are easy—the Audubon’s Warbler’s throat is bright yellow. Myrtle’s, like this one, have white throats.
Females and fall birds can be much trickier. The middle photograph is of a fall Myrtle Warbler that I banded in September 2010, and which I used in my previous post. Note the distinct eye-line and the distinct ear (auricular) patch.  The bottom photo shows an Audubon’s Warbler. Note its more hooded appearance, with an indistinct eye-stripe and its uniformly colored sides to the head.
I handed this Audubon’s Warbler on 8 November 2004 in Aberdeen, South Dakota. Not only is this date fairly late for the species, Audubon’s Warblers are also very rare in the eastern half of the state.

Tuesday, April 22, 2014

Winter Wren

Last week, after hard work, Erika and I turned on our water feature for the season. Running water is a bird magnet. This Winter Wren was one of the first birds to appear—it flew from the backyard adorned with a shiny, new Federal bird band.

Winter Wren systematics are complex and confusing. I have previously posted notes about Winter Wrens in 2010 and 2013. North American birds depend on old-growth forests. Clear-cutting and other logging have greatly reduced this wren’s habitat (Hejl et al. 2002). European Wrens, on the other and, inhabit gardens and urban areas, further evidence that the two populations are distinct species. Our birds, looking like tiny rodents, forage in deep woodland, under snags, in tangles, and among fallen logs. Where they breed, these birds are more often heard than seen. During migration, seeing Winter Wrens can be tricky—except, occasionally, at the water feature.

Monday, April 21, 2014

Review: Rare Birds of North America

Rare Birds of North America by Steve N. G. Howell, Ian Lewington and Will Russell is a fascinating book that most birders will enjoy. The bulk of the book consists of large, lavish, color illustrations of the approximately 262 birds that have appeared in North America five times or fewer. This total is a tad confusing, since the authors consider a flock of rare birds seen but once as a single occurrence. The book also includes a few records that are not officially accepted by the ornithological community.

This coverage presents something of a conundrum since most birders are unlikely to encounter any of these rare species. But browsing this book presents a perfect opportunity for armchair birders to daydream about rare birds and about traveling to where the birds might be found. Presumably by knowing what rare birds look like, birders will be prepared to identify them if the birds are found. On the other hand, having all these illustrations may make it easier for birders to make mistaken identifications.

Species accounts include a summary of where these birds have been seen, their taxonomy, and their distribution. Field marks and similar species are also discussed. Finally short statements about the birds’ habitat and behavior are included.

The 41-page introduction (out of 428 pages in the book) makes for interesting reading. Highlights include a long discussion of the definition of a vagrant bird. Vagrants may be typed into seven classes (e.g., drift or overshooting). These definitions come complete with world maps with hypothetical routes rare birds may have taken to North America. The result is illustrations of paths that look eerily like routes taken by lost jetliners.

Another fascinating graphic indicates those areas areas in which vagrants are most likely to be encountered. Best areas to look for rare birds? Alaska, British Columbia, and the Pacific Coast of the United States. The Northeast Coast is good for rarities too, but, surprisingly second to Minnesota and the Canadian provinces directly to our north. Where do these rare birds originate? If you answer “Latin America,” as I did, you would be wrong! Fifty-one percent come from the Old World, almost twice as many as the 33% from the New World. Pelagic species come in at a distant 16%.

This hardback book costs $35.00, but can be bought on-line at a substantial discount. An eBook version is also available. Both formats can be accessed by clicking the graphic above this post. (I receive no profit from sales and have not been paid by Princeton University Press for writing this review.)

Sunday, April 20, 2014

Mourning Cloak

This individual appears to me to be a very striking Mourning Cloak. Brock and Kaufman write “for winter-weary northerners, few sights can be as welcome as that of the first Mourning Cloak, emerged from its hibernation…during the first spring thaw.” This, our first Mourning cloak of 2014, appeared substantially later than in 2011 (19 April vs. 7 April).

Mourning Cloaks are found across almost all of North America, from northern Canada and Alaska south to northern Mexico. Adults are long-lived, up to ten months.  They emerge in the summer, hibernate during the winter, and breed the following spring. This photo was taken in the Carleton College Arboretum.

Saturday, April 19, 2014

Caspian Tern

Except for Antarctica, Caspian Terns are found around the world. In North America they breed along our coasts and in the interior of the United States and the prairie provinces. Their colonies are adversely affected by changes in water levels, competition with gulls, predators and people. Caspian Terns will often desert their colonies when they are disturbed. Nevertheless, North American populations have increased. In Europe and Africa, however, this tern has declined and is now absent from many parts of the Old World (Cuthbert and Wires 1999).

This Caspian Tern flew overhead as Erika and I explored the South Padre Island Birding and Nature Center on 20 February 2014. These terns subsist almost entirely on fish. They forage with their bills pointing downward. When they find fish, they hover, and then dive, usually completely under water.

Friday, April 18, 2014

Common Gallinule

The birds at the South Padre Island Birding and Nature Center were so tame that I wondered if they were captive. These gallinules appeared to be adorned with red leg bands. This color proves to be a good field mark on any closely observed breeding Common Gallinule. Common Gallinules look like ducks but are actually rails. Note the long, unwebbed toes. This species has had a recent, rocky systematic history. Not so long ago, the ornithologists merged North American Common Gallinules with nearly identical European Common Moorhens, and the resulting species was named Common Moorhen. Now the name has reverted to Common Gallinule, due to differences in calls, bill structure, and DNA.

Common Gallinules are found across much of eastern North America, Mexico, and Central and South America. In many areas they are considered to be game-birds. Bannor and Kiviat (2002) note that the effects of hunting pressure on gallinules is unknown, as are environmental interactions between these birds and other marsh-loveing inhabitants such as muskrats. Wetland pollution and destruction also are threats. The aforementioned authors also relate the story told in Hawaiian mythology that the gallinule’s forehead was scorched red while the bird brought fire to the Hawaiian people.

Thursday, April 17, 2014

Tricolored Heron

We left Atascosa National Wildlife Refuge and drove over to South Padre Island, on the Texas coast. Erika and I had never visited South Padre, and, upon arriving, we figured out why—nothing but high-rise condos and hotels as far as the eye could see. The visit was rescued, however, by my remembering Kirk Mona, a Minneapolis blogger whom I follow, and his post from last January and his account of the South Padre Island Birding and Nature Center. This center charges admission to walk through their small marshland on an elevated boardwalk. Kirk wrote that “there were birds everywhere.” He is right. Most of the birds were tame and easily photographed. Actually the experience was a little like going to a birding Disneyland. I was slightly put off by the zoo-like experience.

Our first bird was this Tricolored Heron. in the 1950s, this species was probably the most common North American heron. Its population was not decimated by the plume-hunters of the previous century. Unfortunately, now Tricolored Herons are declining, often dramatically, throughout their southeastern North American Range. The species depends on estuaries and other coastal areas—habitat that is rapidly being lost to draining, development, and pollution (Frederick 2013).

Wednesday, April 16, 2014

Falcons, Songbirds, and Seriemas

We did not stay at Laguna Atascosa National Wildlife Refuge for very long on 20 February. It was noon, a bad time to look for birds, windy, drought-stricken, and we had plans to visit South Padre Island. We did take a quick drive over to Osprey Lookout, guarded by this spectacular Crested Caracara.
Caracaras are falcons that look like hawks but act like vultures. They share a common ancestor with typical falcons, like the American Kestrel we found later in our trip in New Mexico. More distantly related are forest and Laughing falcons (Morrison and Dwyer 2012). I took this photograph of a Laughing Falcon, in the early 1960s, in Veracruz, Mexico. I have also seen this species in Peru.
Much of the birding world is all a-twitter at the recent discovery that falcons are not closely related to hawks, but are another example of convergent evolution. Their closest relatives appear to be parrots and songbirds. The American Ornithologists’ Union and the newest Sibley guide now place falcons and parrots between the woodpeckers and songbirds (ABA).

The story gets stranger. Genetic evidence suggests that another family of birds, Seriemas, are also closely allied with falcons, parrots and passerines (BirdsEye Birding). Seriemas are odd, South American birds that were thought to be related to cranes. I photographed the Red-legged Seriema in the last photo in northern Argentina in the mid-1960s.

Tuesday, April 15, 2014

Great-tailed Grackle

Great-tailed Grackles also fed at Laguna Atascosa refuge during our February visit. I have previously blogged about this species’ northern expansion, beginning in southern Texas in the early 1900s and continuing by century’s end across much of the central United States, including Minnesota, and even at least three Canadian provinces.

Great-tailed Grackles are fairly omnivorous. Their diet is composed mainly of plant material in the winter; arthropods and other animals in the summer. They are reported to kill small birds, but to leave them uneaten (Johnson and Peer 2001). These authors provide an extensive list of food items, but do not mention fruit, such as the grackle below appears to be devouring. I assume Great-tailed Grackles limit their fruit consumption to bird feeders and that they do not normally attack orchards.

Sunday, April 13, 2014

Olive Sparrow

The National Wildlife Refuges and many of the State Parks in Texas feed birds and build viewing blinds. At Laguna Atascosa refuge we got great views of an Olive Sparrow. This sparrow forages on or near the ground in dense cover. As a result, little is known about Olive Sparrow biology.

This species was a new one for my USA list. I previously listed one in Mexico. Although a common resident from southern Texas south through Costa Rica, Olive Sparrows have large gaps in their range. Many ornithologists believe, among at least 9 races currently recognized, perhaps as many as three species exist—the Texas Sparrow, found in Texas and eastern Mexico, the Yucatan Sparrow, found in the Yucatan Peninsula through Belize and Guatemala, and the Pacific Sparrow, found along the west coast of Mexico. These potential species differ in size and color (Brush 2013).

Saturday, April 12, 2014

Common Loon

As I have written before, loons are among my favorite birds. I was delighted on Wednesday when Penny H. alerted me to a loon at a small pond in suburban Northfield. Common Loons, like the bird in the second photo, search for their prey by swimming while holding their heads under water .
Common Loons usually avoid foraging in deeper parts of lakes. They prefer lake edges between 50 and 150 meters from shore and in areas less than 5 meters deep. Here they find their preferred prey, common at these depths, fish generally smaller than 15 centimeters (Evers et al. 2010).

Friday, April 11, 2014

Dark-eyed Junco

Here is an oddly-plumaged Slate-colored Junco we banded last Monday near Northfield, Minnesota. I do not recall ever handling a junco with such odd facial markings. The bird is clearly in molt—note the feather sheaths on its ear coverts. Are the pale gray supercilliary marks winter feathers not yet molted into dark adult plumage? What about the odd necklace running across its upper breast? That this bird is the Slate-colored form of a Dark-eyed Junco is evident by the sharp angle formed by the edge of its white belly.

Thursday, April 10, 2014

Fox Sparrow


Weckstein et al. (2002) wrote "When John James Audubon found a Fox Sparrow for the first time on its breeding grounds in southern Labrador in 1834, he had no idea that he was looking at one of North America’s most geographically variable birds, with 18 subspecies divided into 3 or 4 distinct groups…”  I have posted a number of times on this species’ taxonomy—use the search box to the right of the posts to pursue this information.

Because of the cold winter, our Texas travels, and other mitigating events, only this week did I get my banding nets set up. We were happy to band three Fox Sparrows, a Song Sparrow, and about a dozen Slate-colored Juncos.

Wednesday, April 9, 2014

Plain Chachalaca

Feeding along with the Green Jays at Laguna Atascosa National Wildlife Refuge were flocks of Plain Chachalacas.  These large birds are in the same order, Galliformes, as turkeys, but they do not seem otherwise closely related. They are assigned to a separate family, Cracidae. In fact, some evidence exists that they are most closely related to Bush Turkeys. Some ornithologists go as far as to assign the Cracidae and the Bush Turkeys to their own order, Craciformes, separate from turkeys, grouse, pheasants and quail (Handbook of the Birds of the World—Alive). In any event, chachalacas are primarily South American species, with only the Plain Chachalaca barely ranging north of the Rio Grande.

Tuesday, April 8, 2014

Green Jay

Early on 20 February 2014 we drove from Rockport south to Laguna Atascosa National Wildlife Refuge. Long-time readers of my blog will recall that, in 2012, it was here that Erika and I first found many of the birds that occur in the United States only along the Rio Grande valley.

Once again, we found our first Green Jays here. Seven races of Green Jay occur in North and Central America. Most of these subspecies intergrade where they overlap. South American Green Jays have a disjunct range and are distinctly colored, have different calls and behavior, are found in different habitat (mountains), and are, thus, potentially distinct species (Gayou 1995).

Monday, April 7, 2014

Couch’s Kingbird

As Erika and I rested at The Rockport Demo Bird Garden and Wetlands Pond, Erika suddenly pointed and said, “Now there’s a different bird!” Our choice was between Couch’s and Tropical kingbirds. Silent birds like this one are very difficult to tell apart. Couch’s Kingbirds have tails that are less notched. Their bills are relatively shorter. They often has brighter olive-green back. Our bird seems to confirm to these field marks. (Banders can often separate them by comparing their culmen-length to wing-length ratios and by the relative length primary five or primary four).

A look in eBird, however, added another clue. The Tropical Kingbird is usually restricted to the lower Rio Grande Valley, while the Couch’s ranges at least to the Rockport area along the Texas coast. eBird did not list the Tropical Kingbird as a possibility for our location.

The first Couch’s Kingbird was discovered by Darius Couch in 1853 and described in 1859. A problem arose thereafter, however, because the bird was “demoted” to subspecies status—just a race of the Tropical Kingbird. Not until 1979, on the basis of their different calls, was the Couch’s Kingbird returned to species status. Due to this hiatus, much confusion exists about just which species older ornithologists studied. Precise details. therefore, are lacking about much of Couch’s Kingbird biology (Brush 1999). In any event, Couch’s Kingbirds range from southeastern Texas across much of eastern Mexico to northern Central America.

Sunday, April 6, 2014

Orange-crowned Warbler

Upon our return from Aransas National Wildlife Refuge, Erika and I stopped by The Rockport Demo Bird Garden and Wetlands Pond. This area is managed by Rockport and the Texas Department of Transportation.

Despite our fatigue from a long day of birding, I entertained visions of finding our first dragonflies of the trip. No such luck. The area is a bit small to attract many birds, and this winter, a bit dry to attract any dragonflies. Orange-crowned and Yellow-rumped warblers flitted around, both common wintering birds on the Texas coast. The Orange-crowned Warbler in this photo was launching itself into the air as I took the photograph. Elsewhere in this blog I have commented that Orange-crowned Warblers are identified by their lack of field marks. Only the faint breast streaking hints as to their identity.

Saturday, April 5, 2014

Pied-billed Grebe

This Pied-billed Grebe kept a close eye on the alligator at The Aransas National Wildlife Refuge on 19 February 2014. I have made several previous posts on this species, which can be accessed through this link.

Grebes are among the most ancient living birds. The oldest fossils are from Chile and are about 80 million years old (Cretaceous). Now grebes are found around the world, but the family is most diverse in South America. Half of the world’s 22 grebes are found in the neotropics.

Grebes were recently thought to be closely related to loons. DNA studies, however, conclude that the two families, due to convergent evolution, are only superficially similar. Today grebes are thought to belong to the same lineage that led to storks, shearwaters, pelicans, and penguins. The origins of loons, however, are more puzzling to ornithologists. Loons may be more closely related to gulls or auks (Handbook of the Birds of the World—Alive).

Friday, April 4, 2014

American Alligator

American Alligators are found in the southeastern United States inland across the piedmont, from Texas to Virginia and including all of Louisiana. By the mid-1960s, hunting and habitat loss had decimated alligator populations. Federal and state protection over the next 20 years have brought the species back from near extinction.

Wikipedia has more information on alligators than you could possibly want to know. This source reports that alligators do not usually regard people as prey. Nevertheless, since 1948, about 5 attacks on people per year have been reported. Alligator bites tend to be serious and the ultimate cause of death may be infection from the wound. As alligator numbers increase and available habitat decreases, alligator attacks appear to be on the rise.

When alarmed, alligators can run on their hind legs, giving rise to Big Foot reports from southern swamps. This alligator paid Erika and me no attention at the Aransas National Wildlife Refuge. We hurried on to the next bird.

Thursday, April 3, 2014

Eastern Meadowlark

On Wednesday morning I drove over to Circle Lake in Rice County, Minnesota, and photographed an Eastern Meadowlark. I have previously written about the travails involved in telling Eastern and Western meadowlarks apart. In this case, identification was not difficult. The bird sang a series of lazy whistles unlike the Western's jumbled notes. Compare these two photos. In the first one, the Eastern, the yellow of the throat does not trespass onto the white lores (the area of the sides of the head between the bill and the beginning of the black necklace). In the second photo, a Western Meadowlark I blogged about last year, the loral area is clearly yellow.
Ornithologists are in general agreement that the meadowlarks are a distinct lineage within the blackbird family. This group is made up of about ten species, including yellow-breasted ones found in North America and red-breasted meadowlarks from South America. The oddest member of the meadowlark lineage is the Yellow-headed Blackbird.

In the early 1900s, Eastern and Western Meadowlarks were considered to be races of the same species. Now, despite occasional hybridization, they are thought to be two very similar species. Based on DNA research and slight plumage differences, many ornithologists consider the Eastern Meadowlarks of the desert-southwest are actually a third species, the Lilian’s Meadowlark. Recent DNA research also indicates that the Cuban subspecies of Eastern Meadowlark is also deserving of species recognition (Handbook of Birds of the World—Alive).

Wednesday, April 2, 2014

Little Blue Heron

Erika and I did not see too many other birds aside from the Whooping Cranes at Aransas National Wildlife Refuge on 19 February 2014. We did photograph this Little Blue Heron. These herons tend to be solitary and can be relatively hard to see. They occur in smaller numbers than do other American herons and egrets (Rogers and Smith 2012). The species is also unique among our herons and egrets because first year birds are white, while adults are dark. Some other species have white and dark morphs unrelated to age. We found this white bird in the refuge. We found the dark bird the next day in South Padre Island.

Little Blue Herons lack aigrette plumes, the feathers that hunters found to be so lucrative in other herons and egrets. Thus this species escaped the decimation that befell other species in the early decades of the 20th century. See my previous post for photos Erika and I took during our 2012 Florida trip.