Sunday, January 31, 2016

Red-bellied Woodpecker

At the home feeders, we have a a pair of Red-bellied Woodpeckers. As indicated by his red forehead, this individual is a male (click here to see a female). These birds are a bit different from other woodpeckers in that they seldom drill wood for food. This woodpecker prefers fruit, seeds, or arthropods.

Recently Red-bellied Woodpeckers have expanded north and west. Most are not migratory, although some northern populations retreat southward during cold winters (Shackelford et al. 2000). None of my banded Red-bellieds have been captured elsewhere.  I have, however, retrapped a couple of my birds ten years after my banding them.

Friday, January 29, 2016

Red-tailed Hawk

On Wednesday, I was working in our sunroom. I looked up from my computer and noticed a Red-tailed Hawk perched high in a tree near our house.  These hawks are fairly omnivorous carnivores, consuming small to medium-sized mammals (rodents like voles, deer mice, and ground squirrels), rabbits, a wide menu of birds, and a few snakes. Tree squirrels, Red Squirrels, chipmunks, amphibians and insects are infrequently taken by these hawks.

Our Red-tailed Hawk tore apart and ate a Red Squirrel. (We did not see the capture, so we do not know if the squirrel was scavenged.) Prey is often taken to feeding perches, but small mammals are usually swallowed whole. Birds are torn apart and plucked before being eaten. Larger prey is dismembered on the ground and the pieces taken to a perch for dining (Preston and Beane 2009).
While our hawk ate, a second Red-tail swooped down through the forest and landed nearby. I do not know if these birds were a pair, or if they were cooperative hunters. The first hawk paid no attention as the second watched it eat.  Red-tailed Hawks are known to steal food caught by other hawks. (They are also known to eat each other.) After about five minutes, the first hawk flew away, carrying the remains of the squirrel. The second hawk followed deeper into the woods.

Wednesday, January 27, 2016

White-breasted Nuthatch

White-breasted Nuthatches are found in southern Canada, most of the United States, and the mountains of Mexico. Most are non-migratory. They survive our harsh winters by caching food throughout their territories. Although I have no banding evidence for my Minnesota nuthatches’ migrating, in some falls, however, some northern and western birds do move south. Grubb and Pravosudov (2008) caution that it is no known if these wandering birds return to their natal regions or if they breed elsewhere.

Monday, January 25, 2016

Glaucous Gull

Glaucous Gulls enjoy a world-wide arctic range. In the New World, they winter into the northern United States. Erika and I saw several among the gulls at Canal Park in Duluth during our New Year’s search for the Ivory Gull. Like many of its brethren,  Glaucous Gulls ominivores, consuming fish, birds, human refuse, and even berries (Weiser and Gilchrist 2012). The smaller bird to the Glaucous’s left is a Herring Gull.

Saturday, January 23, 2016

Pine Grosbeak

Pine Grosbeaks are another visitor from the far North. They breed around the world, usually further south than the redpolls in the last post. On the other hand, they usually do not irrupt as far south when they are found in the northern United States. Last December I photographed this species in Rice County, which is well south of their normal range. Sedentary Pine Grosbeaks also breed through much of the Rocky Mountains.

This female Pine Grosbeak fed at the feeders at the new Sax-Zim Welcome Center on 3 January 2016. The bog lies about 35 miles northeast of Duluth, Minnesota.

Thursday, January 21, 2016

Common Redpoll

Common Redpolls breed across the far northern latitudes of both hemispheres, where they are often the most common songbirds. They irrupt into the northern United States after spruce and birch seed-crops fail, often in alternating years (Knox and Lowther 2000). In my South Dakota banding studies, I found irruption years hard to predict.

This redpoll fed along with a small flock at the new Sax-Zim Welcome Center on 3 January 2016. Males take two years to become bright rosy. First year males are usually not distinguishable from the females.

Tuesday, January 19, 2016

Swamp Sparrow

On 16 January 2016, Gene Bauer called me to say that, for the past few days, a strange sparrow was visiting his bird feeders. Erika and I visited that same afternoon, and the sparrow hopped into view. Gene and I both found it difficult to identify this sparrow. For one thing, we both quickly appreciated how much habitat plays in bird identification. After deliberating, both Gene and I concluded we had a Swamp Sparrow. Pete Dunne‘squote came to both our minds, “The difference between a beginning birder and an experienced one is that beginning birders have misidentified very few birds. Experienced birders have misidentified thousands."

The next noon, with wind chills approaching -30 degrees F, I took these photos. The picture quality is a bit poor since the photos are through a closed window. Opening the window did not help, probably due to the extreme difference between indoor and outdoor temperatures. In any event, that was one cold bird.

Swamp Sparrows breed in marshes, bogs and swamps. In winter they inhabit the southeastern states, Mexico, and the Pacific Coast of North America. Usually in the midwest only north to southern Iowa. This winter Minnesota has about a half-dozen records. This sparrow is secretive and seldom visit bird feeders. Bruce Fall, who confirmed our identification, wrote, "I've never had one in my yard even in migration… Swamp Sparrows are generally rare in the south half of the state in winter, but in most winters from one or a few are reported. I know of a couple that I have found here in the Twin Cities, but they are not often cooperative for relocating them.”

Sunday, January 17, 2016

Gray Jay

Gray Jays also fed on the peanut butter plastered about the Admiral Road bird feeders in the Sax-Zim Bog. These jays thrive in the bitter cold of Northern Minnesota. They are known as Camp Robbers, because of their fearless raids on anything edible. They hoard food under tree bark, gluing it in place with their sticky saliva. Gray Jays breed in late winter. Eggs are incubated at temperatures as low as -30 degrees. Second broods are not attempted in warmer weather. Gray Jays may be declining at the southern edge of their range as a result of global warming (Strickland and Ouellet 2011).

Friday, January 15, 2016

Red-breasted Nuthatch

We raced up to Duluth on 2 January on our successsful quest for the Ivory Gull and Great Grey Owl. We saw few other birds. In my post on the gull, I mentioned that birders fed the bird salmon filets. I wondered if this was different from attracting passerines at a bird-feeder.  Duluth birders have established a few feeders throughout the Sax-Zim bog. The feeders attracted most of the birds we listed.

We were a bit taken aback by the dozen cars of birders parked at a feeder on Admiral Road. The esthetics of the situation were further marred by the birders’ standing around the feeder and outside of their cars. A few birds ignored the birders—Black-capped Chickadees, Gray Jays, and this Red-breasted Nuthatch. A woman spread peanut butter on every available surface—on tree trunks, branches, and even on weeds.  The nuthatch did not seem to mind. The bird took the peanut butter directly from her out-stretched hand.

Wednesday, January 13, 2016

American Coot

Along with the Lyman Lake New Year’s Day Hooded Merganser, I found this American Coot. Coots are North America’s most abundant and widely distributed rail. This species enjoys a wide range of habitat—“including freshwater lakes, ponds, marshes, roadside ditches, and industrial-waste impoundments, as well as in coastal marine” areas (Brisbin et al. 2002). In the winter, they are often found in large flocks. Coots are herbivores. This coot was pulling up and eating aquatic vegetation. They usually forage under water, but also eat grains, grasses and crops on land.

I am surprised at this coot’s color. I usually think of these birds as being black or flat-gray. This individual is practically iridescent.

Monday, January 11, 2016

Hooded Merganser

My 2016 bird list began with this male Hooded Merganser in Carleton College’s Lyman Lake. It swam among hundreds of geese and mallards. With the advent of minus zero temperatures, the waterfall have disappeared and the lake is frozen over.

Hooded Mergansers is our smallest merganser. They are also our only merganser found only in the New World. Unlike other mergansers, the Hooded has a diverse diet—not just fish, but also aquatic insects and crustaceans (Dugger et al. 2009). Behaviorally and taxonomically, Hooded Mergansers are intermediate between the other mergansers and goldeneyes.

Saturday, January 9, 2016

Eastern Forktail

On 31 May 2015, I drove over to nearby Circle Lake. My goal was Eastern Forktails. Despite these damselflies’ being abundant in Rice County, I lacked decent photographs. I discovered my quarry. Forktails were thick along the roadsides. Beatonwrites that all ages of Eastern Forktails perch low on vegetation around the edges of ponds and lakes. This first photo shows what I assumed to be a male Eastern Forktail. Note the double, azure notches along the edge of the end of its abdomen. Note also the green sides of thorax. 
This damselfly acted oddly. It raised its abdomen and then curled it below its wings. This behavior is described by Paulsonfor female Eastern Forktails’ attempting to discourage males after the females have mated. Most females mate only once, after which they repel all other dragonflies. What I presumed to be a male may be an andromorph female
On the other hand, these photos may show some sort of maintenance behavior, allowing the damsel to clean his wings and abdomen. The sides of the thorax seem to be too bright for an andromorph. Usually andromorphs show pale, greenish-blue thorax sides (Lam). Scott King assures me this is, in fact, a male Eastern Forktail transferring sperm from his abdomen tip. Males store their sperm in a pouch under their thorax. Later, females attach to the pouch to fertilize their eggs.
Among the male forktails, I found a few reddish, immature females. These forms are harder to identify than the males. Note the thin black thoracic stripe and the black abdomen tip. Finally I encountered a few adult females. These damsels become quite pruinose (the blueish color covering its body). Identification marks include the complete blue thoracic stripes and the dark color on the upper half of the eye. Females are more likely than males to feed on other damselflies (Paulson).

Friday, January 8, 2016

Lazuli Bunting

The last bird of our July adventure was this Lazuli Bunting at the Theodore Roosevelt National Park. We found this western edition of the eastern Indigo Bunting by following its call. This species calls throughout the breeding season. At first, young males copy the songs of their neighbors. After a while, the males may come up with new syllables, either completely novel, or combinations of several other birds. Occasionally they steal complete songs of an older male. The result is often “song neighborhoods,” in which the songs of local males are similar (Greene et al. 2014).

Thursday, January 7, 2016

Lark Sparrow

Lark Sparrows are another common bird in the Theodore Roosevelt National Park. In a previous post, I described the odd, turkey-like strutting by male Lark Sparrows. I did not mention their odd behavior of passing a twig from the male to the female during copulation. Pairs often use other species’ abandoned nests (Martin and Parrish 2000). This sparrow is common in most parts of their western North American range. They barely reach southern Canada and they winter in Mexico and in the Southwest. They thrive in disturbed areas, like in heavily grazed or fallow fields. We saw it in North Dakota last July.

Tuesday, January 5, 2016

Great Gray Owl

Since moving to Minnesota ten years ago, Erika and I made annual, unsuccessful searches in the Sax-Zim Bog about 40 miles northwest of Duluth. This year’s quest, on our way home from Duluth, appeared to be no exception. We saw few birds and the roads were surrealistically crowded with slow-driving birders. Then, on Owl Ave., a quarter-mile ahead of us, we watched a car make a U-turn and park in the middle of the road. We pulled in behind, and, voila, there sat a Great Gray Owl!

Great Gray Owls inhabit boreal forests and bogs across Canada and south through the Rocky Mountains. They are also found in similar habitats across the Old World. Northern Minnesota is one of the few places in the eastern United States where they breed. In some winters, when prey is scarce, these owls wander further south.

Great Grays look massive, but are mostly feathers, which help during our bitterly cold winters. They are 15% smaller than Great Horned Owls (Bull and Duncan 1993). Great Gray Owls have exceptional hearing. They use their facial disks as parabolic reflectors and can locate voles beneath the snow. One way to know owls are present is to watch for “snow angels” left as the owl crashes through the snow. Notice the exposed ears behind the flying owl’s facial disk

Monday, January 4, 2016

Ivory Gull

On New Year’s Day, an Ivory Gull was reported from Duluth’s Canal Park. Ivory Gulls are circumpolar, almost never seen away from arctic pack ice. Their breeding colonies are widely scattered around the globe. Even in winter this bird rarely ventures south of the Bering Sea or waters off Greenland. This bird’s genus, Pagophila, means “frost-lover.” Erika and I drove the 180 miles to Duluth and spent the next two days looking at the gull and continuing our ten-year search for a Great Gray Owl. We did not have to search for the gull. About 50 birders stood on the ice-covered shore of Canal Park peering at a distant Ivory Gull.
This sighting was fairly unimpressive until the gull flew over and circled the birders. The bird was easily recognized by its small size and buoyant flight. An adult Ivory Gull is pure white. This individual’s black spots and black face indicate that it is a first-winter bird.  
The next morning (2 January) we returned to Canal Park. Almost immediately the Ivory Gull flew in and landed a few feet in front of us. By this time, birders were leaving salmon fillets to attract the bird. (I suppose leaving salmon is not fundamentally different from feeding bird seed to songbirds.) Ivory Gulls are aggressive scavengers. Our bird had no trouble competing with other, larger gulls vying for the salmon.
Ivory Gulls breed in scattered arctic breeding colonies. The total population is estimated to be between 16,000 and 28,000 individuals (Caddy on MOU listerv). Caddy also reports that Canadian populations are rapidly declining. This species, with its almost complete reliance on arctic ice,  is undoubtedly threatened by global warming.

Friday, January 1, 2016

2015 Banding

I felt that 2015 was a poor banding year. Several factors contributed to this conclusion. Erika and I made two extended trips away from Minnesota. Bird populations at my Dundas banding site appeared to be way down. Many days I caught nothing. On the other hand, the fall saw large numbers of Tennessee and Nashville warblers

I banded 894 individuals comprising 62 species. In Northfield, I banded 710 birds. Near Dundas I ringed 160 individuals. I caught 24 other birds at either River Bend Nature Center or Big Woods State Park. I added no new species to the birds-banded list.

My top ten species banded were:

111 Yellow-rumped Warbler 
106 American Robin
90 Tennessee Warbler
71 American Goldfinch
69 Nashville Warbler
47 Hermit Thrush
41 Swainson’s Thrush
39 Black-capped Chickadee
32 Pine Siskin
28 White-throated Sparrow

Species with only one capture were Brown Thrasher, Cooper’s Hawk, Eastern Bluebird, Field Sparrow, House Sparrow, Lincoln’s Sparrow, Northern Parula, Purple Finch, Red-eyed Vireo, and Yellow-bellied Sapsucker. 

The photograph on this post is of a first-year American Goldfinch.