Dan Tallman's Bird Blog

Two Vireos

2013-05-21T07:09:00.000-05:00

Two vireos, a Red-eyed and a Blue-headed, also foraged with the warbler wave of mid-May 2013. Here are photos and links to previous posts about each species.

Red-eyed Vireo

Blue-headed Vireo

Seed-eaters in the Wave

2013-05-20T15:57:00.001-05:00

Among the warblers in our recent wave of migrants, we banded several spectacular seed-eating birds. As in the previous two posts on warblers, the birds’ names are linked to past postings. The goldfinches were most amazing. Very small numbers visited our feeders most of the winter. But our banding station was overrun by goldfinches on 13 May. The woodlot behind our home looked like it was decorated with yellow lights—oddly the vast majority of birds were males. Although they can be found in Minnesota year-round, goldfinches are migratory—so wintering individuals may not be the same birds as those breeding here. Years ago in Aberdeen, South Dakota, I retrapped a goldfinch banded in southeastern Colorado. One of my Minnesota goldfinches was banded near Dundas in April and recovered in July of the same year in far west-central Saskatchewan.

Rose-breasted Grosbeak

Indigo Bunting

American Goldfinch

Black Phoebe

2013-05-19T05:40:00.000-05:00

Black Phoebes are common in California, New Mexico, and elsewhere in the extreme Southwest south through Central and South America. These phoebes are almost always seen near water. This bird hawked insects along the coast at Morro Bay, California. Breeding birds use natural nest cavities, cliff-sides, riverbanks, and hollows in trees. In modern times, most nest in bird boxes. The species is monogamous and often raises two broods per season (Wolf 1997).

Warbler Wave 2

2013-05-17T21:26:00.001-05:00

This post is the second of a series from a migrant bird wave from the second week of May 2013. I have linked the names of each bird to previous posts in which each warbler is discussed. In the middle two photos, note the difference in intensity of the Northern Parula’s chestnut breast patch.

Magnolia Warbler

Northern Parula (female)

Northern Parula (male)

Wilson’s Warbler

Warbler Wave 1

2013-05-16T06:01:00.001-05:00

The second week of May delighted us with a heavy wave of migrating warblers. I wish to share with you a few of the birds we photographed during our banding operations. This photos will occupy the next several blog posts. I have linked the names of each bird to previous posts in which each warbler is discussed.

I noticed that the numbers of migrants were greatest just prior to the passage of two warm fronts through eastern Minnesota. Just before the fronts, winds were from the north. Afterwards, southerly winds prevailed. Presumably those north winds concentrated the migrants, whereas south winds assisted the migrants on their way north. Being a scientist, however, I have entertained two other hypotheses. Migrants appear to flock to my nets just as Erika is setting dinner and 15 minutes before I have appointments away from the banding station. Could these last two hypotheses be coincidental?

American Redstart

Blackpoll Warbler

Black-throated Green Warbler

Blue-winged Warbler

Mountain Sheep

2013-05-15T07:39:00.000-05:00

I took this photo of Mountain Sheep (also known as Bighorn or Rocky Mountain Bighorn sheep) in the Black Hills of South Dakota. Originally these sheep ranged from the Canadian Rockies south as northern Mexico. The race in the Black Hills, the Audubon’s Bighorn, became extinct by 1910. Reintroductions from Montana and Wyoming occurred in 1922, but these animals succumbed to disease in the early 1960s. In 1964 and 1991, sheep from various western states and Canada were again reintroduced (Higgins et al. 2000).

To the best of my recollection, the pictographs of Mountain Sheep come from the Capitol Reef National Park in Utah. I may be mistaken, however, as most rock art in the park were created between AD 600 and 1300 (Utah.com). The two upper figures are clearly on horseback, arguing for a time frame after 1492. (If any of my readers recognize these pictographs as being from somewhere else, please let me know.)

Palm Warbler

2013-05-14T06:26:00.002-05:00

I previously blogged about Palm Warblers last May. On Friday, Erika and I visited the recently burned prairie at the Carpenter Nature Center in nearby Washington Co., Minnesota. I have never seen so many Palm Warblers in one place. The birds actively fed in the burned grass of their managed prairie. Perhaps the ground was warmed by the blackened earth, thereby releasing an insect hatching. Burned prairies do heat up and support elevated plant growth. Prairies are also managed in this was to destroy invasive and non-fired resistant plant species. Unfortunately, frequent burns in relatively small grasslands destroy many rare, prairie-inhabiting butterfly larvae.

Among the Palm Warblers flitted an utterly nondescript bird. What was it? This little gray bird appeared to have few discernible field marks. The presence of a faint wingbar and faint flank and back streaks, along with the slightly brighter crown all add up, for me, to this bird being a female Palm Warbler in basic plumage. Add to that, the fact that this bird was among a large flock of more typically patterned Palm Warblers. Any other suggestions?

Grounded Warblers

2013-05-12T05:36:00.000-05:00

On Saturday, Erika strolled in the East Unit of the Cannon Valley Wilderness Area. The weather was chilly (50 degrees F.) and extremely windy (40 mph gusts). This weather resulted in our finding nine warbler species, many feeding on the ground. On top of that, most of the forest trees lacked leaves, leaving the warblers little opportunity to hide. Here are three of the species we observed:

American Redstart

Blackburnian Warbler

Black-throated Green Warbler

Blackburnian Warbler

2013-05-11T05:47:00.000-05:00

The male Blackburnian Warbler is among the most striking of North American birds (see also this August 2010 post)—but, hey, this female banded on Friday, 10 May, is not too shabby! Actually, it is a bit strange to band a female of this species earlier than a male. Males usually arrive at their breeding grounds at least a week before their mates (Morse 2004). I assume that our 2013, weather-delayed migration may be the cause of this anomaly.

Nashville Warbler

2013-05-10T05:57:00.000-05:00

You may recall my post from last Friday in which I shared a photograph of an Orange-crowned Warbler’s (usually) hidden orange crown. Nashville Warblers, like the bird in this post, are another warbler with a hard to observe crown patch—a chestnut one in this case. Male and female Nashville Warblers are similar, the male being brighter, and both sexes have the crown patch, which is even less evident in the female. I have previously posted a few notes on this species, which, as a lover of secondary habitats, thrives in these days of clear-cutting and landscape disruption.

Golden-winged Warbler

2013-05-09T06:34:00.004-05:00

Previously I have posted extensively on the Golden-winged Warbler (see 14 June and 27 August 2010). This gorgeous migrant was the highlight of a warbler swarm that flew into my Northfield banding station yesterday. Actually I was busy with other obligations, and only had my nets open for an hour, beginning at 11:30 in the morning. In that time I ringed 14 Nashville Warblers, 12 Yellow-rumped (Myrtle) Warblers, 4 Orange-crowned Warblers, 1 Black-and-White Warbler (and saw two others), and observed, but did not catch, a Black-throated Green Warbler and a Blue-headed Vireo. The day was hot (almost 80 degrees) and sunny, but with approaching rain storms. I suspect this “migrant wave” was caused by the birds’ being bottled up to our south over the past few days by snow and cold in Minnesota and a large, low-pressure cell to our south.

Pied-billed Grebe

2013-05-08T06:23:00.000-05:00

This Pied-billed Grebe, a species about which I have previously posted, preened, as the species often does, while on the water, in this case Lake Byllesby in Goodhue Co., Minnesota. Preening often consists of oiling the feathers. The bill and head are used to rub oil on their feathers. The oil is collected from their uropygial gland, an oil gland located near the dorsal base of their tail.

Tree Swallow

2013-05-07T05:56:00.000-05:00

Back on 20 April 2013, Erika and I listed our first Tree Swallows of the spring. The swallows swooped over the Bass Bonds in the Minnesota Valley National Wildlife Refuge along the Minnesota River in Bloomington. We wondered how these insectivores were surviving. These swallows eat mostly flying insects, although they are known to consume vegetable matter during adverse weather (Winkler et al. 2011). This bird appears to be preening, a behavior certainly practiced by Tree Swallows, but not mentioned by the aforementioned authors.

Sapsucker Sucking

2013-05-05T07:56:00.001-05:00

Sapsuckers are famous for drilling holes in trees and then feeding on the sap that flows into the cavities. Yellow-bellied Sapsuckers maintain these holes daily to keep the sap flowing. They defend their wells against other birds—Yellow-rumped Warblers, hummingbirds, other sapsuckers—that may wish to share the sap. Breeding sapsuckers also take various arthropods, but often dip their prey in sap to add to the nutritional value.

This female Yellow-bellied Sapsucker, photographed in late April in Northfield, fed on a maple—but the woodpecker is known to drill into about 100 species of woody plants. In the spring, wells are drilled in xylem, to capture upward flowing sap. Later the birds drill into phloem for downward moving sap. If you look closely, you can see a few wells drilled to the right of this sapsucker. Often sapsucker trees look like they have been machine-gunned by sap wells.

The photo, by the way, was taken on a snowy day and the background is not photoshopped to produce the white background.

Yellow-rumped Warbler

2013-05-04T08:23:00.003-05:00

Yellow-rumped Warblers, Setophaga coronata, until recently were placed in the genus Dendroica. DNA studies, however, conclude that Dendroica, plus the genera Wilsonia and Parula, all comprise a single genus, Setophaga, once containing only the redstarts. Setophaga comes from the Greek and means insect-eater (Gruson 1972). I include this photo because I notice that none of my other posts of Yellow-rumped Warblers show their yellow rump. This bird hawked for insects in late April along Lake Byllesby in nearby Goodhue County, Minnesota.

Orange-crowned Warbler

2013-05-03T14:20:00.000-05:00

In my post of 4 October 2010, I related my instructing students that Orange-crowned Warblers are best identified by their lack of field marks. Faint breast streaking is the salient key to identification. Who has ever seen an Orange-crowned’s crown? Check it out on this bird banded on 30 April 2013.

Orange-crowned Warblers used to be classified in the genus Vermivora. DNA studies conclude that Blue-winged and Golden-winged warblers fall into this genus. Others thought to be Vermivora are only distantly related, and are now placed in the genus Oreothypis. Oreothlypis celata is now the scientific name for Orange-crowned Warblers. Oreothlypis means “mountain bird”—somewhat misleading since, although found south through the North American Rocky Mountains, this species is also breeds from Alaska to Nova Scotia. Celata means “hidden”—a reference to the hidden crown patch.

Prairie Pasqueflower

2013-05-02T06:55:00.002-05:00

On a rainy, cold May Day 2013, Erika and I hiked to McKnight Prairie, managed by Carleton College. Our visit was not accidental—I knew this grassland harbors Prairie Pasqueflowers, and Scott King emailed us they were blooming now. Pasqueflowers (Pulsatilla patens), also known as Prairie Crocus, Wind Flower, or Eastern Pasqueflowers (despite their being absent from most of eastern North America), are among the first prairie flowers to appear, often just after the last winter snows (actually about five inches of snow fell later on May Day and night). Although hearty members of the buttercup family (Ranunculaceae), their blossoms are short-lived. This wildflower is the provincial flower of Manitoba and the state flower of South Dakota (where the lower photo was taken on a much more clement day).

The Dakota people noted this early appearance and believed "its song encouraged other plants to awaken from their winter sleep and come up from the heart of the earth” (Johnson 1999). European Pasqueflower, a closely related species, is often called Dane’s Blood because the wildflower was thought to germinate in places that had been soaked by Roman or Viking blood (Wikipedia).

The genus Pulsatilla is often used as an ingredient in homeopathic medicine, but is highly toxic. It produces cardiogenic toxins and oxytoxins which slow the human heart. Ingestion can also cause diarrhea, vomiting, convulsions, and coma. Blackfeet used pasqueflower to induce abortions and childbirth (Wikipedia)—today oxytoxin, if not pasqueflower, is used to induce labor.

Spring Wildflowers

2013-05-01T07:04:00.000-05:00

With a week of rain predicted, and possibly six inches of May snow, Erika and I took the opportunity of a warm, pleasant Tuesday to stroll in the West Unit of the Cannon Valley Wilderness Area south of Northfield. Despite the previous weeks of cold weather and snow, we discovered a few early spring wildflowers.

First was a White Trout Lily. I have previously posted on this species on 16 April 2012 and 23 April 2011. Trout lilies are pollinated by bees and other arthropods. Because these pollinators can be uncommon in the early spring, the plant also depends on vegetative reproduction (Gracie 2012).

Next we spied one of our favorite wildflowers, the Hepatica. I previously posted on this species on 13 April 2011. These bluish-purple flowers poke out of the leaf-littler and quickly fade to white in the sunlight. Hepatica is able to be one of the first spring wildflowers because its leaves are able to photosynthesize during the winter (assuming, of course, they are not covered by snow).

Spring Beauty comes in a variety of colors, ranging from bright pink to white. Studies indicate that plants with deeper colored flowers produce more seeds than do paler Spring Beauties. On the other hand, slugs prefer eating brighter flowered plants. Flower color is dependent upon the individual plant’s genetics, age, and availability of a red pigment called cyanidin. The situation is further complicated by a fungus that prefers to parasitize white flowered plants. Thus results a delicate balance of color morphs (Gracie 2012).

Finally we found Bloodroot. Previous posts are from 3 April 2010 and 12 April 2011. Bloodroot occur in a natural variant (as opposed to a horticulturally produced plant) with some stamens becoming extra petals, such as the Bloodroot in the last photo. A correlation exists between the petals produced and the number of seeds the plant is able to produce (Gracie 2012). Other Bloodroot have so many petals as to resemble miniature peonies. These plants were collected in Ohio in 1916 and are now occasionally seen in horticultural gardens. In the peony-like Bloodroot, all the reproductive organs (pistils and stamens) are converted into petals!

Wood Duck

2013-04-30T07:31:00.000-05:00

A pair of Wood Ducks visited our Dundas banding station. Although I am not permitted to band waterfowl, we did enjoy the extravagant male and the more subtile, but no less beautiful, female. Wood Ducks are slim birds, able to nest in abandoned Pileated Woodpecker holes, and have large eyes so to more easily fly through woodlands.

In the early 1900s, birders feared Wood Ducks might become extinct—they were over-hunted, forests were being cut down, and wetlands drained. Numbers rebounded mid-century, perhaps due to legal protection and introduction of nest boxes along many waterways. Increasing beaver populations have also created more Wood Duck habitat. Although less hunted than in previous years, Wood Ducks are still prized by hunters. In the eastern United States, this species comprises ten percent of the duck harvest, second Mallards in the number of birds killed (Hepp and Bellrose 1995).

Diving Horned Grebe

2013-04-29T10:16:00.002-05:00

Horned Grebes usually feed in water six meters or less in depth (Stedman 2000). Last week I photographed this grebe in Goodhue County, Minnesota, along Lake Byllesby. I believe the water under this bird is about a meter deep. These grebes swallow small prey under water, but disable larger prey with their bills on the surface. They will also occasionally take flying insects from the air or glean other arthropods from the water surface. About 35% of their diet is fish, while 46% is insects—the rest is composed of crustaceans, small frogs, salamanders, leeches and tadpoles (Stedman 2000). Dives last for up to a minute.

As you can see in the final series of photographs, Horned Grebes are foot-propelled divers. First the grebes flatten their plumage to expel air from between the feathers and their bodies. As they begin their dives, Horned Grebes can spread their feet and legs out to the left and right—this allows them to leap almost straight up and then arch down into the water. When diving, they do not use their wings, which are only used underwater to make sharp turns or avoid danger. In the final photo, only a small splash of water remains—a splash that would please an Olympic diver. A close examination of these photos also reveals that drops of water remain on the grebe’s back throughout the dive!

Vesper Sparrow

2013-04-27T08:00:00.000-05:00

The scientific name of the Vesper Sparrow, Pooecetes gramineus, derives from Lain and Greek for “grass dweller” and “fond of grass” (Jones and Cornely 2002). This species thrives in grasslands but declines when such habitat becomes rare (see my post of 17 April 2011). I took this photograph near Northfield after our late April 2013 blizzard—certainly a candidate for inclusion in a future version of my White Album of bird portraits. A storm like this one is probably tough on these sparrows—experimental data on captive birds show adverse effects after ten hours of fasting.

Purple Finch

2013-04-26T06:39:00.001-05:00

Purple Finches are visiting our feeders. They are known to eat seeds, fruits, and buds from a wide variety of trees and wildflowers. Obviously they are partial to sunflower seeds. They also take insects. Purple Finches tend to be “quasicyclical,” their numbers vary, depending on yearly production of conifer seeds (Wootton 1996). Elsewhere I have posted on this species’ plumage characteristics.

Junco Eats Suet

2013-04-25T07:42:00.000-05:00

This photo is of a junco at our suet feeder in Northfield, Minnesota, during Monday’s 7-inch ice and snow storm. Although juncos are known to consume Spruce Budworms in quantities, Nolan et al. (2002) do not include suet in their list of juncos’ diets. Captive birds increase fat and protein consumption during long light regimes. In any case, the recent snowfalls and cold weather seem to have halted the junco migration here in central Minnesota; juncos have swarmed around Northfield for the last few of weeks. Since 31 March, I have banded over 600 Dark-eyed Juncos!

Swamp Sparrow

2013-04-24T06:54:00.000-05:00

Mowbray (1997) writes that no data exist for Swamp Sparrow nutrition, metabolism, energetics, or temperature regulation. Erika and I came upon this sparrow after a record cold night last Saturday in the Minnesota Valley National Wildlife Refuge in Bloomington, Minnesota. The bird was more interested in the seeds melting from the ice than us.

Yellow-rumped Warbler

2013-04-23T06:55:00.000-05:00

The Yellow-rumped Warblers have arrived. I banded several during the past few days. Previously I have posted on this species’ adaptations for cold weather. Unfortunately for this bird, eight inches of snow fell yesterday night. The photos below show one of my banded birds landing on the baffle below my suet feeder. The bird looked up and discovered the suet, which it proceeded to devour as sleet became heavy snow on April 22nd!