Friday, April 28, 2017

Ruby-crowned Kinglet

Ruby-crowned Kinglets are among the smallest songbirds in North America. (Google assures me that the Verdin is smaller—and hummingbirds are not songbirds.) They do, however, lay the largest clutch for their size of any North American bird—12 eggs (Swanson et al. 2008).

Erika and I encountered this kinglet in the Cannon River Wilderness Area on 22 April 2017. Unlike most Ruby-crowned Kinglets, this one perched stock-still. Usually, they constantly flick their wings. Thus it took me a few seconds to figure out its identity.  Note the thin, white eye-ring and the golden edges to the wing feathers. Without being able to see the color of its crown, you can not tell this bird's sex.

Wednesday, April 26, 2017

Yellow-headed Blackbird

Erika and I found a half-dozen Yellow-headed Blackbirds at the 180th Street Marsh in nearby Dakota County on 24 April. This species is conspicuous in North American prairie wetlands and across western North America in general. Except during migration, this blackbird is seldom found east of Lake Michigan. It winters in the Southwest and in northern Mexico. Ornithologists have recently concluded that this species is an odd relative of meadowlarks (Fraga and Bonan 2017)

Tuesday, April 25, 2017

Swamp Sparrow

Even though you can’t see the side of this bird’s face or its bill, you can identify this species as a Swamp Sparrow. Note the gray eye line and breast. The breast is very slightly streaked. The shoulders and the crown are relatively bright rufous.

As its name suggests, this species inhabits marshes, bogs, swamps as well as brushy meadows. A common bird, it breeds across eastern Canada and the northeaster United States. It winters in the southeastern US and eastern Mexico. I found this individual at Sprague Lake in Rice County, Minnesota, on 23 April 2017. Just like one of my sons, it refused to look at the camera.

Monday, April 24, 2017

Lincoln’s Sparrow

A Lincoln’s Sparrow at the feeders at the River Bend Nature Center on 22 April 2017. Ammon (1995) considers this sparrow to be “among the most elusive of  North American birds.” Its biology is not well known. Not that uncommon a bird, accessing its boggy breeding habitat is difficult. It nests across boreal Canada and the northern United States, and further south through the Rocky Mountains. It winters in the southern US, south into Central America.

Identification is made by noting its thin breast streaking over an ochre wash. Note the gray sides to the head and the bird’s brownish wings.

Sunday, April 23, 2017

House Finch

I banded this mottled red and yellow House Finch at Carleton College on 14 April 2017. Color in House Finches is complicated. Red, yellow, and/or orange color are due to deposition of combinations of 13 carotenoids. These pigments are formed in the blood plasma, liver, and feather follicles. Red and yellow pigment levels vary widely in individual finches. Pigment levels may depend on age, speed of molt, population of finch, and diet (Badyaev et al. 2012).

Saturday, April 22, 2017

Blue-winged Teal

Erika and I found Blue-winged Teal in a small pond on 15 April 2017 in the Carleton College Arboretum.  The flock consisted of three males and three females, not surprising, since teal pairs form in the late winter or as they migrate north.

Blue-winged Teal populations crashed in 1990 after several drought years. By 2000, their numbers more than doubled. This increase may mean, if appropriate conservations are initiated, teal can recover from recent wetland destruction of prairie pothole wetlands (Rohwer et al. 2002).

Friday, April 21, 2017

Eastern Phoebe

We are happy to see (and hear) Eastern Phoebes in the backwoods. They were absent last summer after a hard frost in May. Whenever I band a phoebe, I am following in the steps of John James Audubon. In 1804 in Pennsylvania, he tied small strands of silver thread to the legs of phoebe nestlings. Birds returning the next year still bore the threads. Most phoebes winter in the southeastern United States, some continuing south into Mexico.

Thursday, April 20, 2017

Carolina Wren

Early this morning, I did not need eBird to tell me that Carolina Wrens were rare in Minnesota. This wren was in my banding net. Eckert reports that this species is regular but local and perhaps casual in the state. Most records are during migration and in the winter (in southeastern Minnesota). The Birds of South Dakota suggests that most records in our region are the result of post-breeding dispersal by young birds. On 20 April, however, this individual was clearly an adult.

Wednesday, April 19, 2017

Orange-crowned Warbler

In the Cannon River Wilderness Area on 17 April, the high point of our wildflower walk was actually a warbler. Because of its yellowish belly, lack of wing bars, and faint white eye stripe, I had no difficulty identifying this Orange-crowned Warbler, often a very common early migrant. eBird, when we tried to enter this record, alerted us that this bird was rare! Too early! Turns out that this bird, while not the earliest Orange-crowned Warbler in Minnesota history, is among the earliest.

A documenting photograph was required, but our warbler was not cooperative. It fed low in dense undergrowth. This image was the best I could take. The camera could not auto-focus through all the tangle, and the bird would not come out into the open. If you look closely, notice that it appears to be feeding on a small beetle; Despite the warm day, arthropods were not abundant.

Tuesday, April 18, 2017

Red Admiral and Spring Emphemorals

On 17 April, Erika and I took our annual spring ephemeral hike at the Cannon River Wilderness Area near Northfield. We were not disappointed. We found mats of Wood Anemone (above) and Spring Beauty (below). A half-dozen other wildflower species littered the forest floor. (Ephemerals are wild flowers that bloom before the forest leafs out.)
Common among the ephemorals flitted Red Admiral butterflies. Robert Pyle, in his entertaining book,  Mariposa Road, explains that Red Admirals are misnamed. They should be named Red Admirables. 
Admiral actually refers to butterflies in the genus Limenitis. This name was mistakenly applied to our American butterfly, Venessa atlanta. Pyle consistently refers to this species as Red Admirable. Whatever you choose to call them, these butterflies are highly migratory but can also overwinter. This one probably overwintered, since fresh specimens are more red.

Monday, April 17, 2017

Trumpeter Swan

I find myself slipping behind with blog posts—a good situation, I suppose. Erika and I took this Trumpeter Swan photo on 7 April at the Bass Ponds in the Minnesota Valley National Wildlife Refuge in semi-urban Bloomington, Minnesota. Who knew that swans can make bubbles with their necks?

Trumpeter Swans were reintroduced to our region beginning in the 1960s.  They are now fairly common. Not all swans show such rusty heads and necks. This stain is caused by iron-rich water and mud (Mitchell and Eichhotz 2010).

Sunday, April 16, 2017

Common Green Darner


My first dragonfly of 2017. Migrating Common Green Darners are often the first odonates of the year, appearing even before local populations emerge from their ponds. They fly from as far south as Veracruz, migrating to southern Canada. Migration is assisted by warm fronts, exactly the weather phenomenon that occurred in Northfield yesterday. A warm front parked right on top of us!

I found this individual tangled in my bird net. Dragonflies don’t get stuck in the nets very often, but, when the do, they are often very difficult to free. After liberation, this darner shivered for a few minutes and then disappeared.

Friday, April 14, 2017

Hooded Merganser

Hooded Mergansers appear to be abundant this year. This photo was taken on Cody Lake here in Rice   County, Minnesota. I did a quick literature search and was surprised to learn that ornithologists really don’t know much about current Hooded Merganser population trends. They think that numbers are increasing, but have little scientific data to support that hypothesis (Dugger et al. 2009). Eckert writes that this species is an uncommon breeder across Minnesota, but is more common during migration.

Thursday, April 13, 2017

Bloodroot and Siberian Scilla

Spring just can’t be far off. Bloodroot and Siberian Scilla (Squill) are blooming along the edge of our backwoods. 

Scilla is “a classic case of gardening gone awry” (Minnesota Wildflowers). This pretty, early-blooming flower is introduced to the United States. It is cold-tolerant.  It spreads out of control. Local wildlife ignores it. The plant is hard to eradicate. Broken roots resprout. In other words, this plant, although sold in stores, is a noxious invasive species.

I hope our native Bloodroot withstand the scilla invasion. Bloodroot is also a harbinger of spring. Bloodroot gets its name from its red sap. The sap produces alkaloids that kill animal cells. Bloodroot, although disfiguring, has been unsuccessfully used as a home remedy for skin cancer (Wikipedia). Obviously eating Bloodroot is not recommended and is potentially fatal.

Wednesday, April 12, 2017

Great Blue Heron

On 2 April 2017, this Great Blue Heron hunted the edges of Circle Lake in Rice County, Minnesota. This species is among the most abundant North American wading birds. They mainly eat fish, but also stalk small mammals and amphibians in fields and other upland habitats. They will take almost any animal they can pierce with their dagger-like bills.

Tuesday, April 11, 2017

Yellow-bellied Sapsucker

On 9 April 2017, I banded a female Yellow-bellied Sapsucker. This individual gave me pause, because I thought females’ crowns were red. (Males also have red throats.)

A quick review of the literature indicates the female crowns vary. Often they are red, like the one in this previously posted image. You can find females with black crowns. In the second edition of his guide, Sibley illustrates a black-crowned sapsucker. Crowns can also be “mixed red and black, black with red spots on [the] forehead, or [be] black with buffy markings” (Walters et al. 2002).

Monday, April 10, 2017

Scarlet Cup

Scarlet Cups are called “harbingers of spring” (Smith). These mushrooms fruit from early April through May. I discovered these in the leaf litter below my banding net on 9 April. Amazingly, I found this species at the same location and on the same date in 2011. Scarlet cups are found in North American hardwoods.

Smith does not recommend eating Scarlet Cups, although this fungus is consumed by rodents in the winter and slugs in the summer The Iroquois used this mushroom as an antibiotic to treat the belly buttons of newborn babies. These cups are also occasionally used for table decorations (Wikipedia). 

Sunday, April 9, 2017

Mourning Cloak

Our first butterfly of 2017, despite freezing temperatures the previous night. A Mourning Cloak circled us on 7 April and then landed on the trail in front of us, as Erika and I strolled along the Bass Ponds in the Minnesota River Valley National Wildlife Refuge near Minneapolis. 

In Minnesota, Mourning Cloaks are the first butterflies in the spring. They often emerge in the fall and then hibernate during the winter. Coincidentally, 7 April also marked our first Mourning Cloak in 2011. This butterfly is probably in for hard times, since snow is predicted tomorrow night.

Saturday, April 8, 2017

Mallard on the Roof

Zelda and Scott are our resident Mallards during the ten years we have run our water feature. When approached this year, they flew to the roof of our house. Previously they just flew away. We have no clue if we get the same individuals every year, nor do we know where they nest. 

Friday, April 7, 2017

Red-breasted Nuthatch

Red-breasted Nuthatches are smaller than White-breasted Nuthatches. The Red-breasted has a different call and has different habitat preferences, preferring conifers over deciduous woodlands. They range across Canada and the northernmost United States, with more southern populations in the Appalachian and Rocky mountains. The planting of conifer forests recently caused the species’ breeding range to expand to the south. Unlike sedentary the White-breasted Nuthatch, Red-breasteds irrupt southward, even to the Gulf Coast and northern Mexico, during years with poor conifer seeds. 

A few Red-breasted Nuthatches have visited our feeders this winter. I banded this male on 1 April 2017. I did not remember that this species’ bill is bicolored. In the second image, on the base of the lower mandible, notice the lovely pale horn hue.

Wednesday, April 5, 2017

Eastern Bluebird

On 31 March, Erika and I watched a flock of six male Eastern Bluebirds make their way through a forest edge at the Whitetail Woods Regional Park in Dakota County. We were impressed by the brilliance of their blue.  Bluebirds appear even more brilliant to each other. They see ultra-violet light. Male bluebirds reflect this color especially well (Gowaty and Plissner 2015).

This bluebird shows a couple of interesting features. I expected only young bluebirds to show the yellow base to the bill. If you look closely, notice the white-tipped secondary coverts on the wing. In other thrushes, these tips are held-over juvenile feathers. I suspect this bird, therefore, is a bird hatched last year.

Tuesday, April 4, 2017

Eastern Meadowlark

 
This Eastern Meadowlark sang from the top of a cedar sapling in the Great Western Industrial Park near  Randolph, Dakota County, Minnesota (29 March 2017). I previously posted on the perils of meadowlark identification. The non-gurgly, clear whistle and the yellow throat color not penetrating the sides of its head indicate Eastern Meadowlark.

The Eastern Meadowlark’s range is strange. They breed across most of central and eastern Minnesota and much of the eastern United States. They are almost absent in North Dakota and much of South Dakota. They breed in southwestern South Dakota and, curiously, much of the Southwestern United States, south into Central America.

In any event, this bird’s long hind toes indicate that it forages on the ground. Meadowlarks are generally in decline across North America. Loss of grassland habitat and industrialization of agriculture both contribute to this trend. Severe winters also take a toll on meadowlark populations.

Monday, April 3, 2017

Red-winged Blackbird

Red-winged Blackbirds have made their spring return to Minnesota. This male sang at the Dennison Water Treatment Ponds. The species may be the most abundant bird in North America (Yasukawa and Searcy 1995). Winter populations may exceed 190 million birds. Historically Red-wings were marshland breeders, but changed to nesting in pasture and grain fields. The species has flourished with the spread of American agriculture. Furthermore, Interstate Highway roadsides, with their barrow and drainage ditches, also support this species’ expansion.

Sunday, April 2, 2017

American Tree Sparrow

Another bird present at the Dennison Water Treatment Ponds was this American Tree Sparrow. This sparrow is headed north—the species breeds across remote areas of northern Canada. It winters across the northern and central United States, where it inhabits weedy fields and marshlands. Tree Sparrows often visit suburban bird feeders.

American Tree Sparrows are abundant birds. Somewhat surprisingly, considering their wide habitat tolerances and remote breeding areas, tree sparrows have declined by 53% between 1970 and 2014 (Naugler et al. 2017). Ornithologists do not have an explanation for this downward trend. Industrialized agriculture and loss of weedy fields in their winter range is one hypothesis for the decline.

Saturday, April 1, 2017

Song Sparrow

Song Sparrows are common and widespread across most of the United States, southern Canada, and parts of Mexico. In our part of the world, Song Sparrows are migratory. Many coastal populations are year-round residents. The species occupies a wide range of habitats—often near water—including forest edges, chaparral, marshes, and hedgerows. This bird sang from brush along the Dennison Water Treatment Ponds and, on 28 March, was my first Song Sparrow for this year.

Friday, March 31, 2017

Wood Duck


Reports of Wood Ducks bought us to the Dennison Water Treatment Ponds last Tuesday. My 2017 Year List seems to be progressing at a snail’s pace. We were delighted when a group of four Wood Ducks swooped low over the pond and spashed down in fromt of us. This image shows a drake with a hen.

In the early 1900s, Wood Ducks were thought to be doomed because of habitat destruction and over-hunting. The species has made a comeback, thanks to the Migratory Bird Treaty Act, hunting regulations, and conservation efforts. Expanding beaver populations have also contributed to habitat for expanding Wood Duck populations.

Thursday, March 30, 2017

Ross’s Goose


On Tuesday, Erika and I discovered seven Ross’s Geese at the Dennison Water Treatment ponds in Rice County. Its not every woman who gets dates to sewage treatment ponds! Ross’s Geese are very similar to Snow Geese. The Ross’s Goose’s bill, however, is much shorter than a a Snow’s, the bill lacks a black grinning patch (the line running along the top of the lower mandible), and Ross’s usually show blue warts at the base of their upper mandibles.

In the final photo, you can see the longer, black-ribbed, and non-warty Snow Goose bill. The bird to the right is problematic, since it is clearly larger than the Ross’s Goose to the left.  It does not help that these birds grazed between me and the sun, but, enlarging the photo, seems to show the blue wart field mark. Male Ross’s Geese are, in fact, six percent larger than the females, which may explain the size difference.

The two species also hybridize. In the photo of the Snow Geese (taken years ago in South Dakota), you see both color phases of Snow Geese—white and blue. The blue form is apparently the result of recessive genes in Snow Geese. Very rarely, blue Ross’s Geese are reported. Recent research indicates that  Ross’s Geese lack the blue allele. The blue forms, therefore, are thought to be hybrids between Snow and Ross’s geese breeding back with Snow Geese (Jonsson et al. 2013).

Tuesday, March 28, 2017

Downy Woodpecker Pattern Diversity


Downy Woodpeckers exhibit diversity in their head patterns. This variation allows observers to recognize individuals. The bird in the first photo caught my eye on 24 March 2017 because it seemed to lack the black line that runs from the bill to the shoulder on most Downys. As a result, this individual showed what appeared to be too much white on its head. Compare the first Downy with the one with a normal stripe in the second image taken on 1 January 2017.
The first Downy Woodpecker also sports a black line along the back of its head. Compare that pattern with the woodpecker in the final image, taken 27 February 2013. This difference in pattern is more common than the first. Clearly the books are mistaken that suggest this pattern difference is a way to tell Downy from Hairy woodpeckers.

Monday, March 27, 2017

House Sparrow

On Tuesday at Afton State Park, Erika and I saw something strange at a bluebird house. The opening of the box was protected from mammalian predators by a wire sleeve. We discovered a House Sparrow huddled in the sleeve.

House Sparrows, Tree Swallows, and House Wrens all compete for use of Eastern Bluebird houses. These species will even kill bluebirds during territorial fighting. Even competing female bluebirds are known to kill bluebird competitors. Cold and/or wet weather, however, may be the leading cause of bluebird fatalities (Gowaty and Plissner 2015).

Sunday, March 26, 2017

Sandhill Crane

On Tuesday morning, 21 March 2017, I stopped at a large marsh along side Albers Avenue north of Highway 19 here in Rice County, Minnesota. When I heard the unmistakable bugling of distant Sandhill Cranes, I jumped out of my car. Two cranes circled high over the wetland.

The cranes were probably flying over and defending breeding territory. During the decade since we retired to Northfield, cranes have become increasingly common local breeders. Rice County is near the southern limit of their Minnesota range. Although once common, by the mid-1940s the Minnesota Department of Natural Resources estimated only about 25 pairs nested in the state. Since then breeding cranes have made a steady, statewide recovery.

Saturday, March 25, 2017

Red-shouldered Hawk

Red-shouldered Hawks are considered to be uncommon and local raptors in Minnesota (Ekert). I have seen only a few of them over the past decade. Erika and I found this one actively hunting along the west shore of the Canby Pond along Circle Lake in Rice County. The hawk briefly perched in some small trees before working its way low along the lakeshore.

This bird’s field marks are strikingly evident in the bottom photo. Note the evenly barred, black and white tail. The left wing clearly shows a white crescent towards the tip and reddish-brown shoulders. The right wing is clearly russet underneath, as is the breast.

Friday, March 24, 2017

Golden-crowned Kinglet

On 23 March 2017 I banded two Golden-crowned Kinglets. Both birds were males. This fact may surprise some birders, who assume yellow-crowned birds are females. In fact, the orange crown of this male kinglet is hidden under the yellow feathers. If you look closely, you can almost see an orange hue under the yellow crown.

Golden-crowned Kinglets winter further north than Ruby-crowns. The species tolerates night temperatures below -40 degrees C. At such temperatures, Golden-crowns may huddle together, but they are not known to become torpid (Swanson et al. 2012).

Wednesday, March 22, 2017

Ring-billed Gull

 
I birded a small pond near Circle Lake in Rice Co. on 21 March 2017. About two dozen Ring-billed Gulls greeted me, The flew low to the water around the lakeshore. They tended to bunch up at the north edge of the lake, where the gulls flew against the 32 degree cold wind, Here they flew very slowly, using their legs as air-breakes, The birds carefully watched the water surface, and occasionally wheeling around, diving, and catching prey, which I assume, on such a cold day, were small fish.

Tuesday, March 21, 2017

American Robin

This morning, the first day of spring (20 March 2017), American Robins are everywhere. Because of the worn wing feathers and the pale-tipped wing coverts, I think this may be a second-year bird. I can’t be sure of this birds gender. If it is a local breeder, then this robin is definitely a male, Northfield females have duller backs and gray heads. Female robins from more northern latitudes, however, are often very dark and can not be told from their mates by plumage. Regardless of this bird’s destination, its good to have robin calls once again echoing in the backwoods.

Monday, March 20, 2017

American Coot

Running errands on Sunday, we stopped by Cannon Lake in Rice County. Surprisingly, we saw few waterfowl. We did encounter a flock of about two dozen American Coots foraging on a lakeside lawn. As always, I was impressed with how odd-looking these birds are. They look a bit like ducks or chickens. Their toes aren’t webbed. Instead the toes all have flaps along their edges. Coots are in the rail family, which is classified in the same order as cranes.

Sunday, March 19, 2017

Great Blue Heron

In this strange world of ours, a 2011 computer is an antique. Mine blew its graphics card, which Apple no longer manufactures. So I have a new computer. I spent the last two days upgrading software for my new operating system. This task is time-comsuming and often frustrating—and occasionally expensive. 

Although the job is not quite finished, I am, at least, up and running. I photographed this Great Blue Heron, on 18 March 2017, at the Superior Drive Pond here in Northfield. This winter, a few herons lingered in Minnesota. Migrants have already been seen by others. This bird was my first for the year.

Friday, March 17, 2017

Black-and-white Warbler


The computer from which I blog is experiencing "The Blue Screen of Death." Here is a posting I never got around to last year.

Black-and-white Warblers are a common migrant in Northfield. In the fall, males and females can be tricky to tell apart. In these photos, the male’s underparts are bright white. The female is pale buffy below. Because they winter north to the Gulf and the southeast Atlantic Coasts, Black-and-whites are among our first warblers to appear in the spring. By that time, the males throats have become mostly black.