Wednesday, December 31, 2014

Eurasian Tree Sparrow

Yesterday, Gerald Hoekstra and I drove to a bird feeder south of Hastings in nearby Dakota County, Minnesota. For the last few days, an Eurasian Tree Sparrow was reported from that location. Gerry and I spent over an hour trying to spy the bird among a plethora of House Sparrows at the feeder. We finally noted its chestnut crown (not gray like the House Sparrow’s) and black ear patches. After seeing it a few times, we also recognized the Eurasian Tree Sparrow by the bird's slightly smaller size and paler overall coloration.
The weather—a frigid -5 degrees F., with wind chill warnings posted—did not help finding the bird or taking decent photographs. We had permission by the landowners to watch from the road, but not to enter their property. This was decent of them, but did not allow us an opportunity for closeups. Also not helpful were a flock of Blue Jays that bullied the sparrows from the feeders. These photos are our best effort, the top one by me, and the bottom two digiscoped by Gerry, who very kindly gave me permission to post them here. (The last photo is of the bird in flight, bounding from the feeders to either the ground or to a nearby bush.)
Eurasian Tree Sparrows were introduced to North America from Germany in April 1870. They were released in an effort to "enhance the native North American avidfauna" in Lafayette Park, in St. Louis, Missouri. This initial introduction may have been augmented by subsequent releases. The sparrows rapidly became established in St. Louis, but House Sparrows outcompeted them in the countryside. Eurasian Tree Sparrows slowly spread into Illinois and Iowa—the main breeding range now encompasses about 250 kms from north to south.

This expansion more or less follows the Mississippi River. The species prefers wooded city parks and woodlots. A quick look at eBird illustrates their range and various extralimital sightings. Birds have been sighted around the northern midwest, and as far afield as British Columbia, Oregon, and the East Coast. Ornithologist do not know if these distant sightings are of escaped cage birds, sparrows arriving by ship from Europe or Asia, or individuals originating from their expected range in North America.

The source for most of the information and the quote in this post is Barlow and Leckie (2000). Not included in their account in The Birds of North America is a specimen from Huron, South Dakota, of an Eurasian Tree Sparrow collected on 19 April 2005 by a Purple Martin enthusiast clearing his bird houses of House Sparrows.

Monday, December 29, 2014

Ferruginous Hawk

The mostly white underparts, dark leg feathering extending to the toes, and pale head, all indicate that this raptor is a Ferruginous Hawk. This individual perched on a high-tension pole near Pierre, South Dakota; the photo was taken several years ago.

Ferruginous Hawks are found dry grasslands in the northern Great Plains and adjacent Canadian prairie provinces, and western Washington south to northern Arizona and New Mexico. They winter in the American Southwest and northern Mexico. Their primary prey consists of rabbits, ground squirrels and prairie dogs. The hawks’ numbers fluctuate with their prey.

Ornithologists are uncertain about how well Ferruginous Hawks are faring. Populations appear to be declining in several regions, but there are few data and even fewer hypotheses for the causes. Numbers have definitely declined in some ares of the Canadian prairie provinces and in North Dakota (where they are now absent). More southern populations seem to be holding steady. Some western populations are increasing, while others, in northern Utah and eastern Nevada are decreasing (Bechard and Schmutz 1995).

Friday, December 26, 2014

Swallow Tanager

The third in my tanager series of photographs from my youth is this Swallow Tanager from Limoncocha, Ecuador, taken on 28 June 1976. Regular readers of my blog may correctly guess that this photo is one of a series taken of captive birds in a holding box.

This tanager is so strange that, until recently, it was considered to be in a family of its own, the Tersinidae. Unlike tanagers, this species has a broad, swallow-like bill, long wings, and it nests in holes rather than making uncovered nests. Molecular studies, however, place Swallow Tanagers firmly within the tanagers in the family Thraupidae.

Although the birds are usually at least seasonally common, Ornithologists do not know much about the distribution of Swallow Tanagers across the Amazon Basin and northern South America. Scientists are not clear as to the degree of migration, if any at all, exhibited by this bird.  Some populations may be residents, others short-distance migrants, while still others may be nomadic. Erika and I have records of Swallow Tanagers from eastern Peru in the Andean foothills (Tingo Maria) on 19 June 1972, 14 October 1972, and 1, 2 and 7 December 1972. SwallowTanagers are found forest clearings, coffee plantations, and in canopy tree tops. They consume fruits and arthropods (Handbook of Birds—Alive!).

Wednesday, December 24, 2014

Review: The Warbler Guide App

This amazing app is available at the iTunes Store for $12.99 for iPhones and iPads, and it is worth every penny. (An Android version is coming.) If you make this purchase, be sure you are buying the app and not the book with the same name (unless, of course, you want both formats). 

Some people say, “There is nothing new on this Earth,” but they have never seen The Warbler Guide App. This app is a fast, intuitive way to identify the warblers of the United States and Canada by visuals and/or song. You can quickly access images of all species with comparisons to similar warblers.  Side, face, underside, and head-on views are all available. Similar species are shown on the bottom of the screen.

You can filter the images by region of North America, color, and season. You can even fill in, almost like "painting by numbers," the colors of the parts of the bird you’ve seen, and the app will give you identification suggestions. You can combine this with a description of the song—is it buzzy, clear, or what?  Does the song descend or go up?  The result is that you are presented with just a few of the most likely warblers based on your description.

The app contains a library of songs, with multiple variations for each species. You can set the songs to play at half speed, which may help you to learn them. (The songs’ pitches do not seem to be affected.)

What sets this app apart from anything else I have seen is its 3-D images. You can view a bird portrait and rotate it anyway you want—sideways, upside down (good for under-tail coverts), straight-on, or fleeing.  You can get both close-up and far-way views. You can pick two similar species and rotate them simultaneously.  It’s worth the $12.99 just to see this one feature alone!

The app contains all the information found in The Warbler Guide book, which I have previously recommended in this blog. Range maps, habitat, and behavior of each species are easily accessed. The birds can be arranged by general color, alphabetically, or taxonomically.

You have to see this app—welcome to the new world of field guides….

Tuesday, December 23, 2014

Hepatic Tanager

The second tanager among my old photographs was this Hepatic Tanager, seen at my aunt’s ranch near El Galpon in northwestern Argentina. The date was 27 July 1965. I listed Hepatic Tanagers again in Big Bend National Park on 17 July 1966, and many times in Peru in 1972 and 1973.

I took a double-take when I looked at this photo after all these years. It seems way too red on the head, compared in Hepatic Tanagers in the United States. Our birds have much more dusky ear coverts. A review of Eddleman (2002) reveals that, what we now call Hepatic Tanagers, may actually be three species. The Hepatic Tanager inhabits North and Central America, the Tooth-billed Tanager is found from Costa Rica to Bolivia, and the Red Tanager, like the one in my photograph, encountered in open areas of the Amazon Basin to northern Argentina. (Handbook of Birds—Alive! recognizes these three species, calling them Northern Hepatic, Highland Hepatic, and Lowland Hepatic tanagers.)

Tanager taxonomy is further confused at the genus level. Molecular work indicates that Hepatic Tanagers are closely related to Western and Flame-colored Tanagers, and less so to Summer or Scarlet Tanagers. Furthermore, the genus to which Hepatic Tanagers belong, Piranga, appears to be more closely related to grosbeaks than they are to other tanagers (Handbook of Birds—Alive!).

Sunday, December 21, 2014

Blue-gray Tanager

Recently I discovered photographs of three South American tanagers in my digital files. This first is a Blue-gray Tanager, found in northern South America, north into Mexico. In July 1965, my father sent my brother and me to visit our recently widowed Argentine aunt. We had spent the previous year earning half the trip’s fare. I was 18, my brother 16—we’d both been birding perhaps three years. I took photos during the journey, but with only a 300 mm lens, few of the images are worth sharing. Time has also not been kind to the Kodachrome.

This Blue-gray tanager visited a papaya slice on our balcony in the city of Belem, Brazil. This bird was not a lifer—we boys had already listed it in Trinidad a few days earlier. Blue-gray Tanagers are often found in non-forested habitats, including city parks and gardens and, in fact, thrives in human-altered areas (Handbook of Birds—Alive!). They are known to nest in crevices in buildings.

This tanager’s diet includes fruits, nectar, and arthropods. They are often found in pairs, mixed-species flocks, and loosely associated groups of other Blue-gray Tanagers. This individual appears to be the nominate race, Thraupis episcopus episcopus, found in the Guianas and eastern Brazil, and first described by Linnaeus in 1766. The species is widespread and abundant across its range.

Thursday, December 18, 2014

Band-tailed Pigeon

In the United States, Band-tailed Pigeons occur in two, non-overlapping areas. These populations are considered to be racially distinct, with one occurring from southern British Columbia through California. The other is found from Utah and Colorado south into Mexico. Banding studies show that some individuals trespass between these two ranges (Keppie and  Braun 2000). Other races occur from Mexico into South America. This photo, taken several years ago, is of a dove in the treetops above the Nisqually National Wildlife Refuge.

Band-tailed Pigions have a long nesting season—up to three nests per year—but most clutches have but one egg. Nestlings are “fed curd-like crop milk” produced by both parents. These doves descend from their foothill forests to devour wild and domestic fruits and grains (Keppie and  Braun 2000). Hunting greatly reduced Band-tailed Pigeon numbers in the early 1900s. Hunting still occurs, but this pressure no longer appears to be affecting overall population size. Nevertheless, Breeding Bird Surveys indicate this dove is "decreasing at an average annual rate of 2.8% across its North American range" (Keppie and  Braun 2000).

Tuesday, December 16, 2014

Carolina Wren

Except for posting a photo, I find I have not blogged much about Carolina Wrens. The species is abundant in the American southeast and in parts of eastern Mexico. Here in the upper midwest, this wren is casual throughout the year. I have heard its ringing “tea-kettle, tea-kettle” call once in Minnesota and I seen it a few times in South Dakota. Swanson (in Birds of South Dakota), suspects that most records in that state are the result of post-breeding dispersal by young birds from southern breeding areas.

Perhaps due to warming climate, Carolina Wrens have expanded their range north since the late 1800s. These wrens, however, do not survive cold winters. They do quickly recover from winter setbacks, as they often nest up to three times during the summer, and nests with four or five eggs are the rule (Haggerty and Morton 2014).

This photo appears to be a February 2011 shot taken at the Corkscrew Audubon Sanctuary in Florida.

Sunday, December 14, 2014

Rough-legged Hawk

Large size, black belly, white base to the tail, all indicate that this photo is of a Rough-legged Hawk. Also note the dark underwing splotches on the flying bird’s wrists. John Holden and I encountered this individual in the Burnsville (Dakota Co.) landfill on 10 December 2014. We immediately knew the hawk’s identity because of its hunting habit of hovering above the wastelands surrounding the dump. Rough-legs can be completely black to very pale—I have posted photos of a much paler individual in an earlier post in this blog.

Like the Northern Shrike, Rough-legged Hawks breed across the arctic of both northern hemispheres. In North America, they winter to the southern United States (though they are less frequently observed in the southeast). They consume lemmings, voles, ground squirrels and birds. Breeding and wintering populations fluctuate in response to density of prey populations. Ornithologists do not know if, once in a wintering area, Rough-legged Hawks stay at one location or nomadically search for new areas with abundant prey (Bechard and Swem 2002).

Saturday, December 13, 2014

Northern Shrike

John Holden and I took this photo just west of Northfield on 10 December 2014. Gray, foggy days are not really conducive for digital photography. Furthermore, birds perched on telephone wires do not usually produce very aesthetic compositions. But freezing fog combined with the wires to make this photograph of a Northern Shrike slightly more interesting than I predicted.

Elsewhere I have blogged about identifying Northern and Loggerhead shrikes. The thin black mask that does not traverse the fore-crown indicates this bird is a Northern Shrike. The bill is not as stubby as a Loggerhead's. Especially in the winter, Northern Shrikes consume many small birds and mammals, which they impale on barbed-wire, thorns, and in tree branch forks. Due to their razor-sharp bills, Northern Shrikes are one bird that I do not like to band.

Northern Shrikes are found across the Arctic areas of the Northern Hemisphere. Birds in Europe and Asia, where they are named Great Grey Shrikes, are found further south than are North American ones. Our Northern Shrikes typically move erratically in the winter only to the Central United States.

Northern Shrike systematics are murky. Within North America, ornithologists question if eastern and western races exist. Northern and Great Grey shrikes used to be treated as separate species. In any given sample of Old and New World birds, you can identify about 75% of the birds as to their origin. Does this fact indicate we are dealing with different species or just two quite variable subspecies?  Old World populations may actually represent as many as three additional species. One factor contributing to this confusion is that these shrikes are widely spread geographically, especially in their breeding range, making the collecting of meaningful samples very difficult (Cade and Atkinson 2002).

Thursday, December 11, 2014

Masked Booby

In 2012 I blogged about how eBird added a species to my list, the Nazca Booby from the Galapagos. When I saw them, Nazca Boobies were considered to be a race of the Masked Booby. In 2000, due to differing morphology and ecology, the two races were split into distinct species. Where the two species overlap, they tend not to mate with each other. Molecular evidence supports the split.

In the United States, Masked Boobies breed on the Dry Tortugas, at the end of the Florida Keys. On 15 February 2011, this was as close to the tiny island with roosting boobies as our tourist boat would approach. The captain did oblige me by slowing down, allowing me this photograph.

Tuesday, December 9, 2014

Great Black-backed Gull

On 6 December 2008, when I found the Glaucous Gull in the last post, I also photographed a number of other interesting gulls near the Black Dog power plant in Dakota Co., Minnesota. The pale head, pale, specked body, and black wing tips combine with the heavy, black bill to identify this Great Black-backed Gull. The gulls behind the Great Black-backed Gull are probably Herring Gulls, the dark one being a first year bird.

Great Black-backed Gulls are common in northeastern North America and in Europe. They winter south to the Gulf of Mexico. Feather hunters and egg collectors almost caused this species' extinction. Great Black-backs made a remarkable recovery, and by the 1960s, North American populations probably exceeded their historical numbers and now may be displacing Herring Gulls in New England breeding colonies (Good 1998).

How many gull species are flying in the bottom photograph (taken the same day as the top photo)? I think I can count Great Black-backed (upper left, lower center), Herring (right center), Thayer’s (left center), and, at the lower left, one Iceland gull. The Thayer’s and Herring differ in that the Thayer’s has a reduced amount of black on its wingtip. The Iceland is smaller than a Glaucous Gull, but like the bigger bird, has unmarked wingtips. I have commented on all of these species elsewhere in this blog.

Sunday, December 7, 2014

Glaucous Gull

Inspired by a flurry of reports of Glaucous Gulls in Minneapolis this winter, I searched for my photograph of one taken in Dakota Co., Minnesota, at the Black Dog power plant on 6 December 2008. This date was prior to my blogging career and to my eBirding. Yesterday I submitted an “historical” record to eBird, complete with this picture.

Glaucous Gulls have a circumpolar distribution. In North America, they winter south to California and Virginia. A few also winter around the Great Lakes; this gull is considered to be uncommon in the Minneapolis area. Field marks include large size, large, black-tipped bill, and pale wing tips.

Saturday, December 6, 2014

Buff-tailed Sicklebill

The fanciest bird that I found in my errant hummingbird file is this Buff-tailed Sicklebill. This species was common near Limoncocha, in Amazonian Ecuador, where Erika and I conducted our doctoral research in 1975 and 1976. We also listed the species numerous times in various parts of eastern Peru in the early 1970s. This photo was part of a project we undertook with James Yost to photograph captured birds in a parachute-lined cage.
We caught sicklebills whenever we were near this flower, which I believe is a Campanulaceae, the Bellflowers, a large family containing some 2400 species around the world. My best guess is that it is in the genus Centropogon, which is known to be favored by sicklebills (Handbook of Birds of the World—Alive). The shape of the flower suggests coevolution with the hummingbird, the oddly curved bill perfectly shaped to service the curved flower blossom.
Sicklebills also favor Heliconias, called False Bird-of-Paradise or Wild Plantains, which are closely related to bananas. Heliconias' small flowers grow in the center of long, waxy, colorful, cup-shaped bracts. Buff-tailed Sicklebills practice trap-linning, which is where an individual, rather than guarding a specific flower, visits flowers in a regular, repeating sequence (Wikipedia). I believe the flower in the last photo is Heliconia rostrata, which is known from Peru, Ecuador, Bolivia and Columbia.

Thursday, December 4, 2014

Calliope Hummingbird

Another old photo is of this Calliope Hummingbird, perched atop a pine near Missoula, Montana, on 14 June 2007. Even for the gorgeous Calliope, this gorget seems massively elongated. Why isn’t it a Costa’s Hummingbird? Well, the Costa’s is not found in Montana. Notice the white line that connects the gape to the neck—the Costa’s is dark in front of the eye. Finally, the tail is hard to see on the short-tailed Calliope Hummingbird.

Calliope Hummingbirds are North America’s smallest breeding bird. In fact, this hummingbird is the world’s smallest long-distance migrant (Calder and Calder 1994). Some individuals may migrate some 5600 miles each year between northwestern states and the southwesterm provinces, their breeding range, to southern Mexico, where they winter.

Tuesday, December 2, 2014

Broad-tailed Hummingbird

While writing my series of posts about our 2014 travels to the Southwest, I happened upon an old folder that contained hummingbird photos. I have yet to blog about a few of these species, including this Broad-tailed Hummingbird from Santa Fe on 23 May 2003 at the Randall Davey Audubon Center. The combination of the green crown and rose-red throat readily identifies this male. The proximity of males in flight also can be detected by the shrill, buzzing whistle made by the tips of their tenth primaries.

Broad-tailed hummingbirds breed in the southern Rocky Mountains, eastern California, and Mexico. At higher elevations, where they feast on wildflower nectar, they often go into torpor during chilly nights (Camfield et al. 2013). They usually avoid flowers that they have recently visited and will also take insects. Males make spectacular, swooping displays as their wings loudly buzz.

Sunday, November 30, 2014

Common Eider

With Common Eiders being reported from Duluth in November 2014, I searched my blog for photos I knew I had taken off Martha's Vineyard in September 2009. To my surprise, I have not shared this photo with you.

Common Eiders are the largest ducks in the Northern Hemisphere. The Duluth birds aside, eiders are usually restricted to coastal oceans. An Arctic breeder, many winter as far north as open water remains. Eiders were historically over-hunted, almost to extinction in eastern North America. Populations are now stable despite “increasing harvest pressure" (Goudie et al. 2000).

Friday, November 28, 2014

Purple Finch

On 20 November 2014, while driving across the fields west of Northfield, John Holden and I found a Purple Finch in a farmyard crabapple tree. This species is common across much of the northern United States, southern Canada, and the west coast of North America. This finch winters in much of the eastern United States, where it feeds on buds, fruits, seeds. Purple Finches often are seen at bird feeders.
Purple Finches enjoy “quasicyclical” winter irruptions (Wootton 1996). I assume “quasicyclical” means that finch winter population numbers vary from year to year, but not as predictably as those of other winter finches. Presumably these population swings are the result of yearly variation in northern conifer seeds.
This male Purple finch is at more two years old. First and second year males look like females. Males do not molt into their red plumage until their second September. I shared photos of female-appearing birds in a previous blog post.

Wednesday, November 26, 2014

American Tree Sparrow

On 14 November 2014, Erika and I explored Dakota County’s new Whitetail Woods Regional Park, well worth a visit if you are in the area. The park sports many hiking trails through rolling prairie and woodlands and a small but gorgeous lake.

On this chilly day, we found a flock of a couple of dozen American Tree Sparrows. Naugler (2014) suggests this name is a misnomer, since most of these sparrows breed, often beyond the treeline, in the far north of Canada and Alaska. They winter across most of the northern United States and southern Canada.

Their winter diet includes a wide variety of seeds—about 50% grass, 40% weeds, and 10% other plants. In the summer this diet switches over to nearly 100% animal matter. Naugler (2014) further reports that captive birds drink 29.6% of their body weight in water each day and that wild birds eat snow in the winter. This species is a cold-hearty bird, because, as we Minnesotans well know, eating snow for survival often results in hypothermia in other creatures.

Two races of American Tree Sparrow are described—eastern and western subspecies. Western birds breed in Alaska and adjacent Canada while eastern birds summer across most of northern Canada. Eastern birds have more chestnut, less cinnamon-colored crowns, broader back stripes, and gray rather than whitish edges to their tails.  I suspect my photo is of an eastern bird.

Monday, November 24, 2014

Cedar Waxwing

On 8 November 2014, Erika and I found a small flock of Cedar Waxwings at the University of Minnesota Landscape Arboretum in Carver County. Becuase of its streaky, unkempt plumage, the bird in the first photo is clearly a juvenal. The second bird sports more compact plumage, but is probably an older bird-of-the-year, as evidenced by less distinct streaks—adults are completely unstreaked.  First Basic Plumage (winter plumage), is acquired from September to December.

Saturday, November 22, 2014

Great Blue Heron

During a 31 October 2014 stroll through Carleton College’s arboretum, Erika and I happened upon a late-migrating Great Blue Heron. The rusty-tipped wing coverts indicate this bird is young. Last fall, we also found a late Great Blue, and we found it all the way through December.
As we watched, the heron raised all of its body feathers and then, in the last photo, violently shook them. I was surprised that this behavior is apparently not described by Vennesland and Butler (2011) in The Birds of North America. I assume this shaking is a feather maintenance behavior. The bird was aware of my presence, and it may have been getting its plumage in order in case it decided to flush. I, however, retreated, and the bird walked away.

Friday, November 21, 2014

Red-shouldered Hawk

This week John Holden called to report an oddly colored, orangey breasted hawk perched above his bird feeders near Dundas, Minnesota. “It is relatively tame, and you should have no problem seeing it,” he claimed. Sure enough, on 19 November 2014, when I drove over to see if I could find it, a Red-shouldered Hawk swooped low across his front yard and landed above his backyard feeders.

Red-shouldered Hawks are found in many North American forests and in nearby urban woodlands. The hawks generally hunt from a perch, waiting to spy prey on the ground. John confirmed that his bird spent most of its time looking towards the ground. These hawks eat a variety of vertebrate prey. In Minnesota in the winter, they especially favor chipmunks, mice, and voles (Dykstra et al. 2008). Small birds are also taken, but, curiously, the birds at the nearby feeders paid the hawk little attention (unlike the panic shown when an Accipiter is nearby). Note the bloody belly feathers on the bird in my photo. I suspect those are the result of the hawk’s taking squirrels or chipmunks (and the latter really should be hibernating now). Squirrels are certainly abundant at the feeder. I doubt that smaller prey would leave such a bloody mess.

Janssen (1987) rates this hawk as “casual” in the winter in Minnesota. (Note that Janssen’s book is currently available for a penny through this link—I assume postage is additional.) In the past 30 days, only about a half-dozen eBird records exist for the state.

Wednesday, November 19, 2014

Pine Siskin

Last week Pine Siskins appeared at the feeder. With the advent of bitter cold and snow, we banded a few on 17 November 2014. I have banded well over 13,000 siskins during my career, and have enjoyed a few notable recoveries. None of the birds at the feeder this year appears to be banded, which you might expect from nomadic siskins.

Siskins are an irruptive species, present one year, often absent the next. One assumes this pattern is due to abundance of seeds that the siskins consume. Siskins are odd in that, if food is abundant in a wintering area, siskins often remain to breed, usually very early in the spring. Even across its Canadian and Rocky Mountain breeding range, just exactly where breeding takes place is determined by food abundance (Dawson 1997).

Monday, November 17, 2014

American Crow

I think of crows as being black. I took this photo at the University of Minnesota Landscape Arboretum on 8 November 2014. After developing the image, I was surprised to find the crow to be a combination of violet and, especially on the outer primaries, bluish-green. The back looked scaly. What a beautiful bird!

Verbeek and Caffrey (2002) describe crows’ Basic Plumage exactly as my bird appears. Juvenal birds are dark gray and very young birds have bluish eyes. Towards the middle of summer, they replace all their feathers and enter into Basic Plumage. Apparently, unlike many other passerines, they lack an Alternate Plumage (formerly known as a Breeding Plumage—they breed, instead, in their Basic Plumage). These authors explain that the scaly look is due to non-interlocking distal ends of the back feathers.

Sunday, November 16, 2014

Bald Eagles

On 31 October 2014, Erika and I found two relatively cooperative Bald Eagles along the Canon River in Carleton College’s Arboretum. The raptors perched close by each other. The bird in the first photo seemed larger than that in the second and third. Assuming that the two birds originated from the same area, then the larger bird is probably a female, and, perhaps, the two eagles were a pair. Southern eagles, however, are smaller than northern ones, so, unless you know where they come from, sex can not always be identified by the birds’ sizes.
Both birds peered skyward when a dark juvenal eagle flew overhead. The presumed pair noisily took wing. The female appeared to chase off the male before joining the young bird in flight. The two birds circled the river twice before flying to the north. What appears to be a black band on the bird in the middle photo is an artifact—a shadow from its perch. Both birds appear to be undergoing heavy molt, making them somewhat speckled. This condition means these birds are probably three to five years old.

Saturday, November 15, 2014

Review: Thayer Software Birds of North America version 7

Thayer’s Birds of North America is a robust, yet easy and intuitive to use, program that belongs in every birders’ computer. Recently Version 7 has been released. To see how the program works and to find out why you should own it, see my previous review of a previous version, or watch Thayer’s You-Tube video.

There are a few things you should know about this new version.  First, it is only for the Windows platform. A Mac edition is promised for next spring. Next, Version 7 is free if you already own version 4.0, 4.5, 5.0, or 5.5!  Finally, if you don’t own any of these versions, then the price has been cut in half, from around $100 to $49.95. As a reader of this blog, you can use the code “DAN55057” when you place your order, and the price is reduced by $5.00! Orders can be placed at www.OnelineNatureMall.com or through http://www.thayerbirding.com. Because this program is downloaded from the publisher, it is not available through Amazon.com.

Why upgrade? The program now includes 6,504 photos (versus 3431 or fewer, depending on your current version) and the photos are larger. There are 1499 songs (older versions boasted up to 719). 985 species are covered (vs. 970 or fewer). The general layout and the maps are improved. The program now reflects current bird taxonomy. Finally, the number of videos has increased to 552 from 275 in some of the older versions.

One reason for the price reduction is that the program is now delivered by downloading or via a memory stick. The program is very large, at 6.86 gigabytes, and comes in six separate files. Directions for installing are remarkably clear, but, can take several hours if you have slow Internet service.

I am an enthusiastic, long-time Thayer Birding Software user. Readers of my previous reviews will recall that I required this program instead of a textbook in my ornithology classes. The cost was often less than a classical textbook, and The Birder’s Handbook, a 785-page reference book, is embedded in the program. Among many other aspects, what makes this program such a powerful learning tool is the ability to make customizable quizzes (or you can test yourself using quizzes that come with the program). My students were responsible for any species seen during their field trips. We reviewed birds after every lecture, and soon the students knew their birds well. And, if questions about subtle differences between birds arose, then the students could easily compare species by viewing side-by-side photographs. For more advanced birders, this program allows you to import your own photos and videos. Better yet, you can export photos and videos from the program into your iPod or MP3 player.

Thursday, November 13, 2014

Cliff Swallow

The last photograph we took on our return from Olympia on 25 July 2014 was this Cliff Swallow as it peered from its nest under a South Dakota Interstate overpass. Both sexes build their mud nests. They gather mud, usually within a half-miles of their colony. They bring the mud to the nest and mold it with a shaking motion of their bills. The result is a hollow ball, often with a long, downward entrance tunnel. Birds will often steal mud from nearby nests. The nests are lined with grass, either gasthered nearby or taken form other nests. Nests are generally finished after a day, but are maintained during the breeding season. Unmated males may take over existing nests or begin building a nest in hopes of attracting a female (Brown and Brown 1995). Cliff Swallow colonies can be quite large, often numbering in hundreds of nests.

Tuesday, November 11, 2014

Red-necked Grebe

On our trip home, we split our traverse of endless Montana by taking an extra day to cross the state. On 24 July 2014, we left the Interstate and drove south on State Route 1 up to Georgetown Lake before the highway heads straight east and back to the Interstate. Our target species was the Red-necked Grebe, a bird we lacked for our Year List. We saw this grebe at this location many years ago, so I thought we stood of tolerable chance of seeing it again.

Red-necked Grebes are found from Alaska and northwest Canada, dipping south into Minnesota, the Dakotas, Montana and Idaho—I have also seen the species in South Dakota and Minnesota. They also breed across Asia to Europe. Our birds, as are those from eastern Asia, are larger than European populations. Until 1957, these larger birds were thought to be a distinct species, the Holboell’s Grebe.

As we hoped, we had no difficulty finding a Red-necked Grebe along Georgetown Lake near the highway. This individual swam aggressively back and forth—perhaps the nest lay among some reeds in nearby shallows. In the second photo, note the raised tufts on the back of the head. These crests are often raised during defensive displays (Stout and Nuechteriein 1999).

Sunday, November 9, 2014

Pileated Woodpecker

This odd-looking photograph was taken on a heavily overcast summer day. The picture, taken with a very low shutter speed, captures the essence of a Pileated Woodpecker feeding on the ground—which they do on occasion, when not drilling into woodland trees. The woodpecker uses its long, barbed tongue and sticky saliva to feed on ants and other arthropods, which they extract from tunnels in rotten wood and in the dirt.

The second photo was taken on a bright, November 2014 day of a Pileated Woodpecker at one of our suet feeders. For about 30 minutes, the woodpecker also worked decaying trees in the backyard.

Saturday, November 8, 2014

Pygmy Nuthatch

Kingery and Ghalambor (2001) perfectly describe Pygmy Nuthatche behavior: "Frenetic movements—head first, up tree, down tree, along branches, right-side up and upside down—accompanied by constant chatter, convey the busyness and nervous activity of this gregarious bird as it searches for food.” Certainly this was true for a flock of nuthatches Erika and I found at an Interstate Rest Area in Coeur d'Alene, Idaho, on 23 July 2014. Photographing them was difficult as they bounced through the shady, pine understory.

The species is found in Ponderosa Pines in Western North America and in Mexico. This species is one of the few in North America that practices cooperative breeding. About a third of breeding pairs have up to three male helpers, usually related from previous nests. The helpers feed incubating females and the young and defend the nesting area. Family groups also flock together and with other species, to which they generally are socially dominant. During cold weather, Pygmy Nuthatches are capable of controlled hypthermia as they roost together.  Stacks of up to ten or more birds huddle together, and two articles report more than 150 birds roosting in one tree (Kingery and Ghalambor 2001).