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Red-winged Blackbird

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King of the cattail, the wicked black bird with his yellow epaulets flares his wings, exposing scarlet shoulders and a penchant for conflict. We are encountering, of course, the red-winged blackbird, one of the most abundant birds on the continent of North America.

Their territoriality sticks with many people, be it on bike paths, wetland walks, or a hike near some cattails. Male red-winged blackbirds spend more than a quarter of daylight hours defending territory. A number of hypotheses might explain the fierce defense of red-winged blackbirds. First, the parental investment theory holds that as the age of the nest increases so will the territoriality of the parents. Research suggests this is a strong tendency for red-winged blackbirds, and this theory further predicts that territoriality will increase with an increased clutch or brood size, which is indeed the case for these blackbirds.

Photo by Monica Hall

Photo by Monica Hall

Interestingly, a Journal Sentinel article was published last year on June 29, 2018 detailing red-winged blackbird “attacks” on pedestrians along the lakeshore. These were likely birds with defending nestlings about to fledge; according to the first Breeding Bird Atlas, the median fledgling date was July 1. These blackbird attacks were desperate attempts to protect their investment in young, and the fiercest attackers might have had more young to protect.

Second, the renesting potential hypothesis predicts that nests later in the season will be defended more fiercely due to slim odds of successfully reproducing again so late in the season. Again, this appears to hold true for male red-winged blackbirds.

An unamused sandhill crane getting mobbed by a red-winged blackbird. Photo by Arlene Koziol

An unamused sandhill crane getting mobbed by a red-winged blackbird. Photo by Arlene Koziol

A red-winged blackbird mobs a swan family to protect a nearby nest. Photo by Alrene Koziol

A red-winged blackbird mobs a swan family to protect a nearby nest. Photo by Alrene Koziol

A story, from Antigo on August 11, 2017 shows pictures of a red-winged blackbird attacking and even landing on a bald eagle. According to the photographer, there was a nest nearby. Here, again, we see an extreme example of aggressiveness in this bird, and it can be explained by the renesting potential hypothesis, since the odds of the bird renesting and successfully raising a clutch after August 11 were near zero. The latest date for fledged young according to data from the first Breeding Bird Atlas was August 19, so if the chicks in this nest had not yet fledged, they were likely a second or third nesting attempt.

In summary, early on in the season, early to mid-June, the aggressive birds are likely protecting a nest, and that nest probably is farther along and holding more eggs based on the aggressiveness of the bird. Later in the season, red-winged blackbirds will fiercely defend a renesting attempt, as it’s the last chance for the bird to reproduce that season.

While extremely common and abundant, red-winged blackbirds have undergone a 30% population decline since 1966. This might be attributed to a number of factors, including continent-wide wetland losses and degradation. While we’re not at risk of losing red-winged blackbirds any time soon, their overall decline suggests a worsening of habitat, especially for wetland birds.

Red-winged blackbird nest parasitized by a brown-headed cowbird in an upland setting. Photo by Drew Harry

Red-winged blackbird nest parasitized by a brown-headed cowbird in an upland setting. Photo by Drew Harry

Another reason to protect these wetland habitats is that red-winged blackbirds have reproductive success in wetlands and marshes. According to the Breeding Bird Survey, only 2% of nests in marshes were parasitized by brown-headed cowbirds, whereas 17% were parasitized in upland settings. Nest success was 48% in wetlands but only 33% in uplands.

At Faville Grove you can find boisterous red-winged blackbirds throughout the sanctuary. They’ve just returned to the area in the past week.

 Written by Drew Harry, Faville Grove Sanctuary land steward

Cover photo: Kelly Colgan Azar

Black-billed Cuckoo

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On a June morning, I struggled my way through the wetland margin of the Laas Tamarack. Wanting to find what breeding bird species resided in this largely inaccessible and otherworldly tamarack bog, the allure of the unknown was soon filled with regret and rubber boots full of murky bog water. This was to be expected.

A brushy tangle of tamaracks and understory. Photo by Drew Harry

A brushy tangle of tamaracks and understory. Photo by Drew Harry

Many of the birds I heard and saw were also expected: yellow warblers, robins, gray catbirds, red-winged blackbirds, common yellowthroats, cedar waxwings, chickadees, wood ducks, and a green heron. Delightful, no doubt, but they didn’t include any of the hoped-for birds, like a mourning or Canada warbler, or a white-eyed vireo. The sunrise through the tamaracks, in combination with the morning dew, gave the needles a bluish tinge. Meanwhile I appreciated the treasures of the bog: pink lady’s slippers orchids, unique sedges like cottongrass, and blueberry and huckleberry. Of course, the hummocks of sphagnum moss offered a delightful color palate of red, green, and brown; while also varying the topography so that I had to listen for rare birds instead of also looking for them.

After wandering around the outskirts of the tamaracks and appreciating the sunrise, I stopped and touched a particularly burly young tamarack. From this tree, at about eye level, flushed a good-sized bird that jolted me back from the tree; a moment later I realized it was a black-billed cuckoo, and a moment after that I saw it had flushed from its nest. Here was a delightful find!

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The nest defied the warm and homely expectation of care instructions for eggs. Instead, the black-billed cuckoo that I found opted for a few sticks crudely stitched together in the crook of the tamarack. I would not make it back into the tamarack to monitor the nest, but with a frail gust, those eggs could have easily tumbled to the ground.

This type of nest construction is actually typical for black-billed cuckoos. While cuckoo relatives in England will parasitize the nests of other birds, the black-billed is less likely to do so, but still has been known to lay eggs in the nests of other birds. I’d like to think the cuckoo, upon finding the nest of a robin and envious of the cozy design, decides instead to squat its eggs in the more hospitable robin nest.

Cuckoos, more often heard than seen (with their three-noted coo-coo-coo), thrive in brushy and gangly thickets. Where I found this cuckoo nest, I had to cross a wetland edge of a few feet of water, then stumble my way through an almost impossibly thick maze of shrubs and small trees. This is just how the cuckoo likes it.

The beautiful, but intimidating to hikers, tamarack bog. Photo by Drew Harry

The beautiful, but intimidating to hikers, tamarack bog. Photo by Drew Harry

Where I’ve encountered cuckoos in thickets, they’ve been hilariously hard to spot. I might excitedly point out the bird to our summer interns, only for the bird to sit still for minutes on end. When it starts moving again, it’s still hard to spot with its brown to olive plumage and namesake black bill, but a white underside and red eye ring reveal flashes of this brilliant bird. I recall one summer when I looked at a black-billed cuckoo with the interns, and the bird seemed to mirror our movements through the brush. Here we were, hunched over and rocking our head every which way, and there went the cuckoo, looking at us, moving quickly in short spurts and navigating the jungle of brush.

Black-billed cuckoo photo by Tom Murray, FCC

Black-billed cuckoo photo by Tom Murray, FCC

During the breeding season, black-billed cuckoos are relatively common throughout Wisconsin. However, indices of population from breeding bird survey routes suggest a steady decline of the cuckoo population in Wisconsin. Since habitat in Wisconsin is sufficient to support this species, it is thought that spraying for gypsy moths might affect food availability, or pesticide spraying may kill caterpillars and thus eliminate an important food source.

Cuckoos love caterpillars, and where you have an outbreak of caterpillars—especially tent caterpillars—you will often find cuckoos. Breeding bird survey data from Wisconsin reflects this element of cuckoo ecology, as the density of black-billed cuckoos is highly variable, and peaks every 8 or 9 years, almost always coinciding with a caterpillar outbreak. One interesting adaptation that black-billed cuckoos have to eating sometimes spiny caterpillars is that they shed their stomach lining, coughing it up in a pellet.

You won’t be able to find any cuckoos right now at Faville Grove, and you’ll likely have to wait until mid to late May to see one, but North Shore Road is a reliable spot to find this secretive bird.

Written by Drew Harry, Faville Grove Sanctuary land steward

Black-necked Stilt

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We were very excited in May when it appeared that a pair of black-necked stilts might nest at Goose Pond... and were very disappointed when they left us.

Black-necked stilts with their black neck and long, skinny legs are is easy to identify by looking at field marks of shorebird photos in bird identification books.

Black-necked stilt ready for its glamour shot. Photo by Arlene Koziol

Black-necked stilt ready for its glamour shot. Photo by Arlene Koziol

Sam Robbins in 1991 wrote in Wisconsin Birdlife that their status was accidental with only four records. The first record was in 1847 when a flock was seen at Racine and one was collected. The second record account in 1951 was of an individual at Horicon Marsh. This bird was also collected for a museum collection. The next record in 1986 was also from Horicon Marsh, and in 1987 a stilt was sighted at Schoeneberg Marsh/Erstad Prairie. Luckily for the stilts, by the 1980s photographs were used instead of shotguns to verify rare sightings. 

Black-necked stilts are a southern species that is usually found from the gulf coast to the southwest states. On their wintering areas, stilts are frequently found with avocets, another large and colorful shorebird. Researchers reported a stable to increasing stilt population between 1966 and 2014.  In the past 25 years, stilts have expanded their breeding range north.

Black-necked stilt parent and chicks. Photo by Richard Armstrong

Black-necked stilt parent and chicks. Photo by Richard Armstrong

In 1999, Jack Bartholmai, an expert observer and photographer, recorded the first black-necked stilt nesting at Horicon Marsh. Their population has slowly expanded at Horicon Marsh and this spring 30 individuals could be found. In 2004 a pair nested at a wetland restoration in Jefferson County, and last year a pair raised young at the Mud Lake State Wildlife Area near Reeseville in Dodge County.

Black-necked stilts copulating. Photo by Richard Armstrong

Black-necked stilts copulating. Photo by Richard Armstrong

Jim Shurts and Mark found our pair of stilts on May 13 on the east pond (the wetland attached to Goose Pond, but privately owned on the east side of Goose Pond Road) while our team conducted our Great Wisconsin Birdathon. For the next 10 days, we frequently saw stilts, and most sightings were from the flooded food plot north of the west pond and south of Kampen Road. Richard Armstrong photographed them copulating on May 17 and Mark saw them copulating two days later. Mark also saw a stilt aggressively chasing a late-migrating yellowlegs from the area where they spent a lot of time, and where we thought they would nest.  Stilts nest near water and we were considering fencing off the nesting area to protect they nest from ground predators. 

Graham Steinhauer, our Goose Pond Sanctuary land steward, saw the stilts for the last time on May 23. Sam Robbins would have never guessed in 1990 that stilts would nest in Wisconsin. Next year we hope they return -- and nest this time -- and then they can then be recorded as a “confirmed nesting” instead of “probable nesting” in the Goose Pond block of the Breeding Bird Atlas II.

Written by Mark Martin and Sue Foote-Martin, Goose Pond Sanctuary resident managers

Cover photo by Arlene Koziol

Henslow's Sparrow

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Photo by Arlene Koziol

Photo by Arlene Koziol

The Henslow's sparrow is a small songbird with a dull brown body and a streaked breast. This bird is restricted to open habitats, typically grasslands, of the midwest and northeast. Over winter, these sparrows spend their time in longleaf pine and bog habitats of the southern US. The pairing of globally rare breeding and wintering habitat makes the bird rare across its range. Endangered in seven states and threatened in Wisconsin, the Henslow's sparrow would seem a banner bird for grassland conservation.

Yet, the Henslow's sparrow lacks the iconic status of the dickcissel or meadowlark. The sparrow's understated plumage and faint call—a simple tsillik—undercut its zealous heaves. David Sibley describes the call as a “feeble hiccup.” Additionally, the bird is notoriously difficult to spot. Hiding in a dense accumulation of litter a Henslow's sparrow will whistle its call, unseen. If approached, the bird often flees on foot, its brown feathers matching the dullness of a few year's foliage.

The nest resides on or near the ground, where the female incubates eggs for approximately 11 days. Chicks will occupy the nest for about 9 days, being fed a diet of grasshoppers and caterpillars.

As far as managing for Henslow's habitat, the birds present an interesting dilemma. On one hand, Henslow's sparrows need two to three years of litter accumulation in order to breed in an area. Conversely, the birds tolerate a low amount of brush and need dense stands of grass for suitable habitat.

Burning will maintain the open habitat and stimulate grasses, but the sparrows dislike nesting in recently burned areas.

Photo by Carloyn Byers. Read more about Henslow's sparrow nesting in our    Into the Nest series   .

Photo by Carloyn Byers. Read more about Henslow's sparrow nesting in our Into the Nest series.

Henslow's sparrow nest, drawing by Carolyn Byers. Read more about Henslow's sparrow nesting in our    Into the Nest series   .

Henslow's sparrow nest, drawing by Carolyn Byers. Read more about Henslow's sparrow nesting in our Into the Nest series.

A patchwork of burning, like we have here at Faville Grove, can encourage Henslow's sparrows to nest in an area.  Areas with multiple years of standing dead vegetation provide cover and nesting areas for these discrete birds. Recently burned prairie provides good foraging habitat, and the dense cover of new growth can hide fledgling chicks.

This past week, the interns and I stumbled upon multiple Henslow's sparrows in the sanctuary. We first heard the calls of dozens of other birds, eventually focusing in on the Henslow's repetitive calls. Standing in a field of smooth brome, the calls seemed bromidic, or trite. As we sat there for five minutes, the bird finally emerged onto a cup plant and hoisted its unenthusiastic call our way. The bird may not be a banner for conservation, but it belts out its calls oblivious to human concerns, embedded in a mosaic of grassland habitat.

Written by Drew Harry, Faville Grove Sanctuary land steward

Eared Grebes

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In 1968 Madison Audubon was celebrating the acquisition of the first purchase at Goose Pond Sanctuary. Also in 1968 Sam Robbins celebrated his rare finding on July 6 when he found two newborn young eared grebes riding on the back of an adult in St. Croix County. This is the only eared grebe nesting record for the state.

Eared grebes are small grebes with a peaked head and a thin bill. They are stunning in breeding plumage with their chestnut sides, black head and neck with golden feathers fanning out behind the red eyes.

Photo by John Kendall (Flickr CC)

Photo by John Kendall (Flickr CC)

Eared grebes are the most numerous grebe in the world and three subspecies of eared grebes Podiceps nigricollis are found in Africa, Europe, and Asia, as well at North America. Podiceps means "vent" or "anus" and pes translates to"foot"; this is in reference to the attachment point of the bird's legs—at the extreme back end of its body. The species names nigricollis is Latin for "black-necked": niger means "black" and collis means "neck". In Europe they are called black-necked grebes.

Sam Robbins in 1991 wrote in Wisconsin Birdlife that eared grebes are an uncommon migrant and casual summer resident. There were only four observations in Wisconsin from the late 1800’s up to 1940. After that there were almost 100 records from 1940 to 1985. Sam wrote “This species favors such shallow prairie ponds as …. Goose Pond. On two occasions individuals summered at Goose Pond” (1956 and 1965).  

Eared grebe pair at Goose Pond. Photo by Richard Armstrong

Eared grebe pair at Goose Pond. Photo by Richard Armstrong

The first Wisconsin breeding bird atlas from 1995 – 2000 only found two pairs of grebes and none were confirmed nesting. Minnesota completed their breeding bird atlas in 2013 and confirmed eared grebes nesting only in five blocks. This is a very rare species in Wisconsin; however, researchers estimate the North American eared grebe population is stable at 3.5 – 4.1 million. Most grebes nest in the Great Plains, including in Canada. Years ago we were on an MAS field trip to North Dakota and toured a large prairie wetland and observed several thousand nesting eared grebes. 

Tom Wood, from Menominee Falls wrote on the June 4 WisBirdNet email listserv “there have been 3 Eared Grebes at Goose Pond in Columbia County for at least a few days. This morning I sat on the bench overlooking the west pond. This bench is across the road from the informational kiosk. They were on the far side of the pond so a scope was needed. Two are in breeding plumage and the other partially in breeding plumage (black head with golden plumes, but foreneck rather brownish)."

“Grebe Team” of Sumner Matteson and Daryl Christensen. Photo by Mark Martin

“Grebe Team” of Sumner Matteson and Daryl Christensen. Photo by Mark Martin

The DNR “Grebe Team” of Sumner Matteson and Daryl Christensen surveyed Goose Pond on June 12 and found the pair constructing a second platform in the open water area. They also found a male red-necked grebe (state-endangered) and eight pied-billed grebe nests. This spring there was a horned grebe on the pond. Goose Pond and Rush Lake are the only wetland in Wisconsin where four species have been found in a given year.

Grebes build nesting platforms and we were excited to see the grebes carrying arrowhead stems and constructing a platform. Carrying nesting material is a “confirmation” for most birds except for wrens. We also learned from Nick Anich, DNR Atlas Coordinator, that eared grebes build copulatory platforms. They may build a number of platforms and we have seen them constructing three platforms.

Eared grebe building nesting platform at Madison Audubon Society's Goose Pond Sanctuary in June 7, 2018; video by Patrick Ready

Photo by skinnybrager (Flickr CC)

Photo by skinnybrager (Flickr CC)

We and many others are watching for the pair to begin nesting. Hopefully in July there will be some cute little grebes riding around on their parents backs. The young can climb, swim, and feed an hour after hatching. If you want to see the grebes, a spotting scope is very helpful and you should visit sooner than later since the arrowheads are rapidly growing and the pond will be green instead of blue in a few more days.

We are holding a 50th anniversary celebration on Saturday August 18th and we hope you can join us and hopefully we can also celebrate the second nesting pair of eared grebes in Wisconsin. 

Written by Mark Martin and Susan Foote-Martin, Goose Pond Sanctuary resident managers