Friday, October 31, 2014

Pacific Forktail

On 21 July 2014 our family visited the Hand’s On Children’s Museum in Olympia, Washington. Who knew that I would need my telephoto lens? In the middle of the water lilies in a small, decorative pond flitted a Pacific Forktail, a new damselfly for my list. (Generally we were disappointed in the relatively low numbers of dragonflies observed during our western trip, and this was the last one we saw.)

I had to make do with my short lens, focusing through a glass window, and greatly enlarging the photo—never excellent strategies for producing stunning wildlife photos. At least I had a sunny day! Especially if you enlarge this image on your computer screen, you can see this species’ salient field marks. At least four pale blue spots grace the top of the thorax. No other forktail in the Pacific Northwest sports such spots (Paulson 2009). The urban habitat also fits well. Paulson writes, “in the Northwest, more likely to colonize backyard ponds than other damselflies.”

Thursday, October 30, 2014

Rough-skinned Newt

The McLane Creek Nature Trail, near Olympia, was developed by the Washington Department of Natural Resources. Although only a mile long, the trail winds through forest and wetlands and is a great place for birding. We walked the trail on 20 July 2014.

A new creature for us, however, was not a bird, but this Rough-skinned Newt. This amphibian is common throughout western Washington and along the West Coast. This species is likely to be found out in the day, perhaps because its skin is highly toxic and is avoided by predators. The toxin is the same that is found in pufferfish and can induce paralysis and death. Only the Common Garter Snake can survive eating a Rough-skinned Newt (Washington DNR). The DNR warns that these newts "can be handled safely but care should be taken with small children prone to putting things in their mouths. After handling any amphibian, one should avoid touching the mucus membranes of the eyes, nose and mouth until hands have been washed.” People usually just suffer skin irritation, although one person, on a dare, is reported to have swallowed a Rough-skinned Newt—he died (Wikipedia).

Rough-skinned Newts are usually terrestrial, and move to ponds to breed. A few populations remain in ponds through the summer but migrate back to land in the fall. Others remain in ponds all year. Reproduction is aquatic. Adults breed when they are about five years old, and may breed every other year. Males arrive at ponds, transform into their aquatic phase, and wait for the females. When a female enters the water, males rush to grab her. The successful male hugs her from the back until she is ready to have her eggs fertilized. The male then deposits a sperm sac and she picks it up with her cloaca.  The eggs, which are also toxic, are deposited on submerged plants.  The eggs hatch into larvae, which become terrestrial after about a month, or they may overwinter and transform the next summer (Californaiherps.com).

Wednesday, October 29, 2014

Hooded Merganser

This young Hooded Merganser rested at the McLane Creek Nature Trail, near Olympia, Washington, on 20 July 2014. Unlike the nearby Wood Ducks (see last post), Hooded Mergansers are single brooded. Males abandon the nest cavities when the females begin incubating. Females are on their nest for about a month. The hatchlings leave the nest within a day of hatching, in response to the females' calling to them. The ducklings feed themselves, even on their first day out. They are capable of diving, but often feed with just their heads underwater. They eat aquatic invertebrates. The young fledge after about 70 days. Banding studies show that some young fly up to 700 km north in the fall before moving south in the winter (Dugger et al. 2009).

Tuesday, October 28, 2014

Wood Duck

Wood Ducks breed in nest boxes and in tree cavities. They are among the few North American ducks that nest twice in the same season. Often, but not always, this second brood is laid by older females. The second brood is usually smaller than the first. The number of eggs laid by females depends not on her age, but on her weight.

Wood Ducks often lay their eggs in other Wood Ducks’ nests. Hooded Mergansers will also lay their eggs in Wood Duck nests. Rates of this nest parasitism vary, but have been reported in some populations as high has 85% for nests with other Wood Duck eggs and 39% with Hooded Merganser eggs. The rate of parasitism is apparently correlated with how easy it is to see the nest cavity. The average number of eggs in non-parasitized nests is 9 to 12; parasitized nests can host up to an average of 22 (Hepp and Bellrose 2013).

Erika and I photographed this male Wood Duck as it warily eyed us during a stroll in the McLane Creek Nature Trail, near Olympia, Washington, on 20 July 2014.

Sunday, October 26, 2014

River Otter

Writing this post, I was surprised to learn that River Otters are found throughout North America. I only knew them from the Boundary Waters Canoe Area of northern Minnesota. They are, however, rare in some parts of their range, as they are sensitive to pollution, over-trapping, urbanization, and wetland destruction. Reintroductions have been successful in other areas where they have disappeared.

On 19 July 2014, Erika and I visited the Nisqually National Wildlife Refuge near Olympia, Washington. Otters burrow near water and can submerge under water for almost eight minutes. This habit makes them somewhat difficult to photograph. Otters eat small fish and various amphibians, crayfish and even turtles (National Geographic).

Saturday, October 25, 2014

Review: Beetles of Eastern North America


J. S. B. Haldane, the famous British geneticist, is reputed to have been asked by a theologian about what conclusions the study of evolution might have on the nature of God. Haldane replied, assuming the Lord spent most of his time creating the creatures He liked best, and there being so many beetles on the planet, then the Creator must have “an inordinate fondness for beetles.” Beetles make up to one-fifth of all plant and animal species found in eastern North America.

The Beetles of Eastern North America is written by Arthur V. Evans and published by Princeton University Press in 2014. Naturalists will enjoy this stunning guide. Most of the 560 pages are illustrated with up to four, large, color photographs of various beetles—1500 photographs in the whole book. Each photograph is accompanied by a short paragraph describing the species and a bit about identification, habitat and range. You can take a peek at some of the pages by clicking on the link at the top of this review.

An illustrated key to the most common of the 115 beetle families found in eastern North America begins the accounts. 1409 species are included in this book. The problem is that this total is fewer than 10% of the beetles of the region. Thus this book is more of an introduction to beetles of the East, rather than a field guide. Furthermore, only experts with hand lenses can separate many beetle species. In fact, many beetles lack common names.

Those wishing to learn more about beetles will enjoy this book's introduction. Anatomy, behavior and natural history, and where to find beetles are all covered. Subsequent sections talk about observing, photographing, and collecting beetles—and, if you are really taken by studying beetles, how to keep and rear them in captivity.

Friday, October 24, 2014

American Bullfrog

Bullfrogs are native to eastern North America but have been introduced across the country and around the world. These introductions have been accidental or on purpose—they are considered a delicacy and escape from farms, they have been used as biological control agents, or they may be escaped pets.

Where established outside of eastern North America, they are invasive species. Female Bullfrogs lay up to 25,000 eggs, and, after about two years, hop out of their ponds onto land (MN DNR). The concern is that Bullfrogs may out-compete, native amphibians and unbalance local ecosystems. Bullfrogs are voracious, opportunistic, ambush predators that capture any small animal they can overpower—rodents, small reptiles, amphibians, crayfish, birds, and bats have all been found in Bullfrog stomachs (Wikipedia).

On the other hand, Bullfrogs provide nutrition to their predators, including herons, otters, large fish and snakes. Bullfrogs may be resistant to copperhead and cottonmouth venom—an interesting hypothesis for study if one were looking for a thesis topic.

This bullfrog and many others hunted under the algae-covered pond at the Nisqually National Wildlife Refuge near Olympia, Washington. I confirmed my identification with a refuge ranger, who made an unhappy face and said, “I wish they weren’t there."

Thursday, October 23, 2014

Caspian Tern

This Caspian Tern flew by us at Nisqually National Wildlife Refuge on 19 July 2004. The tern is flying in a typical posture, with its bill pointed downward. When a fish is spotted, the bird hovers and then plunges, often completely going under water. Fish are the Caspian Tern’s main staple.

I have blogged about these terns before; indeed, this observation is my second for the year—the first being on the Texas coast in February. This tern occurs on all continents except Antarctica. In North America, they breed both coastally and in the interior. American Caspian Terns winter south to Colombia and Venezuela. Our populations are increasing, unlike those in Europe and Africa, where they are often rare or extinct (Cuthbert and Wires 1999),

Tuesday, October 21, 2014

Barn Swallow

The Nisqually National Wildlife Refuge near Olympia, Washington, has a long boardwalk across the mudflats at the south end of Puget Sound. On 19 July 2014, Erika and I discovered this Barn Swallow family under the eaves of a covered bench along the walkway. Pandaemonium broke out every time an adult flew up to the nest, but the adult always flew in and out before I could snap a photograph.

Barn Swallows tolerate extra adults at their nests. These extras may help at the nest for an entire breeding season and are not necessarily related to the nesting pair. This situation sometimes leads to polygyny. Other helpers may replace a deceased pair member. The extra adults do not help much in feeding the young, but do assist in building the nest, incubation, and brooding. A nest with helpers is often “owned” by an older female, and the hypothesis is that male attendants are trying to secure high-quaility mates. Juveniles from first broods also help at the nest. In this case, the helpers do supply substantial amounts of food. Occasionally unrelated juveniles serve as helpers.

Sometimes extra adults are chased off. Curiously, reproductive success is not affected by the presence of adult helpers. The extra adults are most often found when swallow populations have a skewed sex ratio, and not all individuals can find a mate or a nesting site. Related juvenile helpers benefit from the experience of “baby sitting,” and assuring the survival of their parents’ genes. Why unrelated juveniles would be tolerated is less clear (Brown and Brown 1999).

Monday, October 20, 2014

Savannah Sparrow

Like the Least Sandpiper I wrote about in my last post, the abundant Savannah Sparrow has a wide range across North America. Also like the sandpiper, the sparrow usually returns to its nesting area. This behavior often results in reproductive isolation and genetic differentiation among breeding populations. Unlike the monotypic sandpiper, 17 subspecies of Savannah Sparrows have been described by ornithologists. To see some of this variation, look at my posts of birds from Minnesota and Florida. This sparrow was first named by Alexander Wilson, when he collected the first specimen near Savannah, Georgia (Wheelwright and Rising 2008).

Sunday, October 19, 2014

Least Sandpiper

Least Sandpipers are “moderately abundant,” and have the broadest and southernmost breeding range of all the small sandpipers across the arctic and subarctic (Nebel and Cooper 2008). In a previous post, I mentioned that eastern populations make nonstop 4,000 km migrations from New England to their South American wintering grounds. Western birds migrate through the Midwest or down the Pacific Coast.

Erika and I were actually a tad disappointed that such a common sandpiper was the only shorebird we listed on 19 July 2014 at Nisqually National Wildlife Refuge. (The dark back and the yellow legs are keys to its identity.) Being relatively small, bird censuses may tend to under-count this species. Nevertheless, studies suggest significant declines in numbers during recent decades (Nebel and Cooper 2008).

Least Sandpipers are monogamous and lay a single clutch, therefore one might expect them among the earliest of the fall migrants. They also have “a high degree of breeding-site fidelity,” thus it is somewhat surprising that they do not differentiate across their wide range—no subspecies are described (Nebel and Cooper 2008).

Saturday, October 18, 2014

Blue Dasher

Abudnant  across much of North America, Blue Dashers often perch at in trees and bushes.  They often hold their wings forward. The blue abdomens, yellow-striped sides, and white faces all conspire to cinch identification. Erika and I found about a dozen dashers perched on a barbed wire line, with each dragonfly facing  rather stiff wind, on 18 July 2014, south of Moses Lake, Washington.
The next day, on 19 July, we found another Blue Dasher, this time at Nisqually National Wildlife Refuge. A photo of that dragonfly is included below. This beautiful day did not produce a dragonfly until after noon.

Friday, October 17, 2014

Band-winged Meadowhawk

Until about 2000, dragonfly experts considered eastern and western populations of Band-winged Meadowhawks to be separate species. These meadowhawks tend to have pale wing bands in the east, much like in the first photo of a Band-winged Meadowhawk in the Carleton College Arboretum on 24 August 2013. Western populations tend to have much darker bands, at least at the outer edges of the wings. The middle photo was taken last July at Potholes State Park just south of Moses Lake, Washington.
The problem is that Band-winged Meadowhawks in our area of Minnesota tend to be intermediate between the eastern and western populations and lot of variation exists, even within different populations. Notice the dark outer regions of this last Band-winged Meadowhawk from Erika’s garden on 8 July 2014. Recent genetic studies suggest that all Band-winged Meadowhawks constitute a wide-spread and variable species (Forbes 2009).

Thursday, October 16, 2014

Striped Meadowhawk

On 18 July 2014, as Erika and I drove from Missoula, Montana to our destination in Olympia, Washington, the sky quickly became hazier and darker from smoke from forest fires in Washington and British Columbia. The sky was so dark on the Idaho border that I took a photo of the sun in midmorning. The smoke over Spokane, Washington, was down-right apocalyptic—opaque reddish brown. Emails from family in Olympia warned that the Interstate passes were closed with no visibility and multi-car crashes blocking the highway. Thus we found ourselves in western Washington, heading south to Highway 12 and White Pass. Almost immediately the smoke cleared.

Potholes State Park just south of Moses Lake, is a great place to search for dragonflies. My ode-guru, Scott King, had mentioned the possibility of Striped Meadowhawks during our journey—and that is exactly what greeted us at the state park! This striped thorax is distinctive, at least for adults. Rarely do I know a dragonfly's identity the first time I see it.

Striped Meadowhawks range in western North America from British Columbia to the Southwest, and east to the western Great Plains.  Males defend territories in weedy area and over grassy lawns.  More than other meadowhawks, they often perch in shrubs, and are usually found near water (Paulson 2009). The individuals we photographed were perhaps a quarter-mile from Potholes Reservoir.

Tuesday, October 14, 2014

Blue-headed vs. Cassin’s Vireos

This October I banded several Blue-headed Vireos. I have previously posted on this species. In 1997, genetic studies split the Solitary Vireo into Blue-headed, Cassin’s and Plumbeous vireos. Looking at this rather dully plumaged female, I wondered if a Cassin’s Vireo would be recognized if it wondered into Minnesota from the Pacific Northwest or from somewhere else in the far West.
Plumbeous Vireos, which nest in the southwestern Rocky Mountains, northeast to the Black Hills, are actually found closer to Minnesota than are Cassin’s. Plumbeous Vireos are much darker birds, with slate-gray sides. But Cassin’s Vireos could stray into Minnesota. I believe the bottom photo, which I took in southern Arizona in 1970, is a Cassin’s Vireo. Key field marks of a Blue-headed Vireo include: 1) the gray of the head sharply contrasts with the white sides of the throat; 2) the back of the is much brighter than most Cassin’s Vireos; and 3) Blue-headed Vireos are bright white below, unlike the dingier Cassin’s Vireo. My October birds, as expected, were all Blue-headed Vireos—but I remain vigilant.

Sunday, October 12, 2014

Four-spotted Skimmer

Not all the dragonflies that Erika and I found along the Madison River on 17 July 2014 were new to us. I quickly recognized this Four-spotted Skimmer. Clicking the link will take you a previous post on the species, which is found across much of North America and the northern Old World.

Saturday, October 11, 2014

Western Forktail

On 17 July 2014, Erika and I found another new odonate for us along the Madison River, Gallatin Co., Montana. The green thorax stripes and the blue-notched tip of the abdomen are indicative of the Western Forktail. Separating Eastern from Western Forktails can be nearly impossible in the field, but, fortunately, only the Western is found in western Montana—the Eastern venturing only to the Dakotas and eastern Montana, Wyoming, Colorado and New Mexico.

Males like this one are usually vastly outnumbered by their females. Similar to the Eastern Forktail, females need copulate only once, and then use one male’s sperm to fertilize their eggs. By fluttering their wings and curling their abdomens, the females, in fact, often repel males’ advances (Paulson 2009).

Friday, October 10, 2014

American Bittern

I still don’t know how John Holden saw this American Bittern. On Wednesday morning, we drove slowly across the 180th Street Marsh in Dakota County, Minnesota. “Stop the car!” shouted John, “I think that’s a bittern!” “Where?” I asked. “Right in front of us,” he exclaimed. “Where?” I asked again, “In the green grass?” “No, in the corn field.” Only when the bittern finally moved, did I finally see the bird.
I never thought to look for a bittern in a corn field—they usually inhabit wetlands. They favor marshes with tall reeds or cattails, where they cryptically blend into the background. Bitterns usually do not pursue their prey, but wait motionless for the prey to come to them. They are usually most active at dawn or dusk. In a previous blog post, I wrote about the bitterns’ declining numbers due to wetland degradation and destruction.
But the bittern was not finished with us. The bird casually strolled out of the cornfield and walked towards us across a dry, grassy patch. Now and again it struck and consumed prey—what appeared to us to be either grasshoppers or perhaps small frogs. (They also eat other insects, amphibians, crayfish, small fish, and even small mammals.)
When disturbed, bitterns sometimes freeze or even play dead—but this American Bittern walked right up to our car, so close I could no longer take photos. I got out of the car and took more photos.  The bittern did not move, though occasionally it puffed up its neck feathers. Only when I turned around to my side of the car did the bittern fly the short distance back to the cornfield. 
Lowther et al. (2009) comment that “remarkably little is known about basic aspects of [bittern] biology.” They are usually too secretive and their habitats too inaccessible. Erika and I marveled at the last photo—the eyes clearly afford the bittern with binocular vision, and the eyes are oddly placed on the bottom half of the head. Perhaps this placement allows the bittern to keep its eyes on you while it points its bill skyward to further blend into its environment. 

Thursday, October 9, 2014

Turkey Vulture

Erika and I kicked up a Turkey Vulture along the roadside on a very windy 3 October 2014. The black-tipped bill suggest that this bird is relatively young. I was impressed this bird’s ragged plumage. Almost nothing is known about Turkey Vulture molting patterns (Kirk and Mossman 1998). Molt may continue throughout the year.

Turkey Vultures are one of the few birds than have an acute sense of smell. When Erika and I were in Ecuador, beetle collectors visited us. On the jungle floor, the entomologists left leaf-covered coffee cans laced with excrement. These traps did not wreak, but quickly attracted numbers of vultures, even though the birds could not see the bait. I have read that oil companies sometimes locate pipeline leaks by pumping carcass odor into the pipes and then waiting to see where the vultures congregate.

Wednesday, October 8, 2014

Downy Woodpecker Deformed Bill

On 9 June 2014 I banded a male Downy Woodpecker with a deformed, elongated bill. Having previously banded a Black-capped Chickadee with a deformed bill, this woodpecker record is my second for deformed bills at our Dundas banding station.

Allaboutbirds.org reports that an Alaskan study found 25 species with deformities. Contrary to that report, none of the Alaskan birds were first-year birds (Van Hemert, pers. com.). Other banding studies found that deformities develop in birds between six months and two years of age. My woodpecker was over two years old, as evidenced by its black primary coverts (but, of course, this age does not indicate when the bill began developing abnormally).  This woodpecker does not seem to be in very good health, its feathers are soiled and its weepy eye is surrounding by missing feathers. I have not recaptured or seen this individual since the initial banding.

What causes bird to develop abnormal bills is not known. Hypotheses run from injury, disease, parasites, poor nutrition, genetic defects, exposure to contaminants, and exposure to extreme heat (Allaboutbirds.org).

Tuesday, October 7, 2014

Review: National Geographic Complete Birds of North America, 2nd Ed.


Today, 7 October 2014, National Geographic is publishing the second edition of its book, Complete Birds of North America. This 744-page guide lists for $40.00. The book is edited by Jonathan Alderfer, and written by “America’s top birding authorities.” The guide is touted at a “companion” to the National Geographic Field Guide to the Birds of North America.

This guide is in search of a slightly different niche than other bird books on the market. It is not a field guide. For one thing, it has slightly larger dimensions than the Sibley Guide to Birds, and is about 140 pages longer, and relatively heavy, making it impractical to take into the field. You would use it to identify birds after a field foray. This new book has much more text than a typical field guide, and that is its strength. Birders’ attention is verbally directed to salient field marks.

Twenty-one artists contributed the uniformly excellent color illustrations for this book. Frustratingly, the illustrations often do not allow multiple, side by side species comparisons. Many of the illustrations are the same as in the 6th edition of the National Geographic Birds of North America. The back cover, however, boasts that 600 art “pieces” are new. About a 44 species are new to this edition; there are about 200 more pages.

Range maps are large, clear and updated. Unlike Sibley’s field guide, accounts that deal with subspecies have maps showing the races’ ranges. Racial range maps were included at the end of previous Geographic field guides, but having the maps on the same page as the account is more convenient. Furthermore, the illustrated subspecies are clearly labeled, unlike in Sibley, which does not include a race’s scientific name.

Unique in the new Complete Birds of North America are box-essays on difficult identifications. These essays include photographs. Photographs of single species also accompany family introductions throughout the book. These family accounts also mention pertinent taxonomic issues. The text includes sections on identification, similar species, geographic variation, voice, status and distribution, and population trends.

Curiously lacking is any in-depth discussion of other aspects of avian biology and ecology. For example, heat conservation by small birds does not seem to be mentioned. Hybridization is not discussed between Black-capped and Mountain chickadees in areas where both species overlap but are scarce. On the other hand, hybridization between Black-capped and Carolina chickadees is mentioned and the reader is wisely warned “where the two species occur together, it is probably best to leave many of them unidentified.”

The Complete Birds of North America's target audience is probably the intermediate to advanced birder. I think any birder should give it a close examination, either at a bookstore or by clicking on the link at the beginning of this review. Finally, no birder would turn down a gift of this book.

Sunday, October 5, 2014

Eight-spotted vs. Twelve-spotted Skimmer

One problem with Montana is that  its almost impossible to drive across and search for birds and dragonflies at the same time. I have a favorite rest area where Interstate 90 crosses the Madison River near Three Forks in Gallatin County. This spot is not an official rest area, but a fishing access off the frontage road on the north side of the Interstate.

Despite windy, chilly conditions on 17 July 2014, a few dragonflies chased each other above cattail-edged pools. At first I thought these were Twelve-spotted Skimmers, like the one in the second photo from the Lebanon Hills Regional Park near Minneapolis (photographed in July 2013). But they appeared a bit odd. The wings seemed short, maybe because they lacked terminal black spots. The white spots on the hind wings blended together. The abdomens appeared very bright blue-gray.

All dragonflies should be so easy to identify! These odes were my first Eight-spotted Skimmers. This dragonfly is found across much of the western United States, east only to Colorado and Wyoming. The skimmer was difficult to photograph until one repeatedly returned  to a nearby perch. Paulson (2009)describes this behavior well, saying they "move constantly, not defending fixed territories…[showing] much aggression to other males of their own and other similar-sized species."

Saturday, October 4, 2014

Black-headed Grosbeak

Roughlock Falls in the South Dakota Black Hills is an easy place to find Dippers. We spied this semi-aquatic land-bird, but they did not cooperate for photographs. We did find a pair of Black-headed Grosbeaks feeding among the cars in a parking lot—presumably searching for car-killed arthropods.
Black-headed Grosbeaks are closely related to Rose-breasted Grosbeaks. The two species hybridize in the Great Plains where their ranges overlap. Some ornithologists consider them to be well-marked races of the same species. Alan Phillips named the resultant species, the Common Grosbeak. This hybridization, however, occurs in areas of low density and patchy habitat. It is not as frequent as where Yellow and Red-shafted flickers or Indigo and Lazuli buntings meet (Ortega and Hill 2010).

Friday, October 3, 2014

Least Chipmunk

On 16 July 2014, Erika and I drove across South Dakota. Along the way, we drove through the Badlands National Park and stopped at Roughlock Falls in the Black Hills. We added a new mammal to our photography collection—a Least Chipmunk. At first I thought the first chipmunk, from the Badlands, and the second one, from the Black Hills, might be different species. This rodent turns out to be quite variable, with pale individuals found in arid habitats and more richly colored, tawny ones in moister areas (Higgins et al. 2002).

As the name implies, the Least is the smallest of the chipmunks. It has, however, the widest range of any chipmunk—found in western North America from the Yukon south to Arizona and New Mexico. Least Chipmunks occur at many elevations and consume a wide variety of vegetation and insects. They are not true hibernators and, in the winter, move about in their burrows where they consume food caches.

Thursday, October 2, 2014

Yellow-breasted Chat

This Yellow-breasted Chat was the highlight of our stop at the Cliff Shelf Nature Trail in South Dakota’s Badlands National Park. As we walked through the cedars along the loop, I heard a unfamiliar bird song. I am not sure why I would recognize it as a chat, since male chats have song repertoires of around 62 song types. Chats often mimic other species’ calls (e.g., robins, buntings, vireos, kingfishers and yellowlegs) (Eckerle and Thompson 2001). Chat songs are given, however, at a relatively low frequency, which may have been what tipped me off.

I banded this large warbler annually in South Dakota, but never photographed one. Ornithologists have long argued just what a Yellow-breasted Chat is—the bird seems too big to be a warbler. The songs are far more varied than in other warblers. The behavior and some anatomical features differ from typical warblers. Genetic data, however, support the chat’s being an atypical but definite warbler.

Wednesday, October 1, 2014

Rock Wren

Erika and I saw several Rock Wrens during our July stop-over at the Badlands National Park in South Dakota. The birds gave us a mini-course in Rock Wren eating habits. Studies in Utah have compiled a list of 13 insect orders being eaten by Rock Wrens. Lowther et al. (2000) that Rock Wrens mostly eat insects, mainly crickets, grasshoppers, ants, leaf-hoppers, bugs and beetles. We concur. The bird in the first photo seems to be consuming a grasshopper or cricket. The second wren has a butterfly or moth caterpillar, an order known to be on the Rock Wren’s menu.