Orange-crowned Warbler

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

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

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

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

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

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

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

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

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

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!