Scarlet Tanager

The scarlet tanager, ostensibly one of the most beautiful birds in Wisconsin, can be a wonder to behold for the first time (and any time, really). This neotropical migrant and breeding season resident can typically be found in mature oak woodlands. Almost all of the tanagers I've seen have been in mature white oak trees, shimmering on burly branches ornamenting the Quercus alba.

Photo by Kelly Colgan Azar

One might ask, “why are scarlet tanagers so red? Doesn't that make them more visible to predators?” Indeed it likely makes them more susceptible to predation, however it also makes them more visible to potential mates. It's been found that a gene is likely responsible for the red pigment in tanagers, and other red-feathered birds. The gene is expressed in not only the skin, but also the liver of these red birds. It is theorized that the birds with the brightest plumage could also have the healthiest livers and are thus able to break down toxins in the environment. Adult tanagers will often feed on diverse samplings of berries, and the gene responsible for the red color may aid in the elimination of toxins from the diet.

Biodiversity Heritage Library

If the female finds a sufficiently red male to mate with, she'll begin constructing a nest high in the canopy with an assemblage of twigs. Usually completed in 3-4 days, the nest is composed of leaves, bark, and grasses. Nest building starts around this week, and eggs are typically found by the middle of June, with 3-4 eggs per clutch.

Scarlet tanagers prefer larger forest tracts, but can still be found in smaller forest fragments. Here at Faville Grove, you might find these birds in Faville Woods or in the savannas surrounding the Kettle Pond. While these birds can be more easily seen than heard, if you get close enough you can't miss this beautiful sign from the tropics.

Written by Drew Harry, Faville Grove Sanctuary land steward

Great Wisconsin Birdathon Count - Columbia County

We spent an enjoyable Mother’s Day participating on the Natural Resource Foundation’s Great Wisconsin Birdathon, listing the birds we found and thinking of how our mothers would have loved being part of our Reckless Wrens team consisting of Mark Martin, Sue Foote-Martin, and Jim Shurts. We split up for part of the day between different birding hotspots in order to cover as much quality habitat in Columbia County as possible. In the end, we found 122 species, a record for the Reckless Wrens. 

Rose-breasted grosbeak, photo by Mark Moschell

Sue surveyed the Martins' Wildland property near Rio and found 29 species in the 160-acre wetland, prairie, and savanna habitats. Madison Audubon Society holds a conservation easement at Wildland. The feeders were crowded with ruby-throated hummingbirds, Baltimore orioles, rose-breasted grosbeaks, and American goldfinches. Highlights included a pair of trumpeter swans, a prothonotary warbler, and pine siskins. We hope to confirm nesting pine siskins as a first for the Breeding Bird Atlas II in Columbia County.

Sue also found six species of woodpeckers including a red-headed woodpecker in the savanna restoration. Other good finds were the great egret, Wilson’s snipe, black-throated green warbler, orchard oriole, and purple finch. 

Mark and Jim surveyed Goose Pond and Otsego Marsh. Goose Pond Sanctuary was unbelievable! Sixty species were found including 14 species of waterfowl. Waterfowl highlights include a greater white-fronted goose, gadwalls, northern shovelers, northern pintails, green-winged teal, redheads, lesser scaup, buffleheads, a female hooded merganser, and ruddy ducks. 

Jim found what at first he thought to be a female canvasback. The duck was all brown, had a sloping forehead, and as it was swimming with a “purpose”, it appeared tapered in the rear.  Mark had a good look at the bird just when Jim interrupted, “A shorebird just landed in the water!” Forgetting about the duck we had a great look at a male Wilson’s phalarope. Males are dully colored since they incubate the eggs. We could not relocate the unknown duck but from our observations we believe it was a scoter - species unknown. 

Wilson's phalarope, photo by Becky Matsubara

The highlight of the day was seeing two shorebirds in the distance land in the east pond wetlands. They were black on top and white on the bottom. We had permission and walked to the far edge of the Manthe farm, where we were rewarded with observing a pair of black-necked stilts, an uncommon bird in Wisconsin.

Black-necked stilts, photo by Arlene Koziol

Also found at Goose Pond where horned grebe, American bittern, sora, dunlins, and short-billed dowitchers.

American bittern, photo by Arlene Koziol

Otsego Marsh was also very productive where we found 39 species. We hiked the trail and began with a female rose-breasted grosbeak carrying nesting material. We found nine of our 11 warbler species at Otsego Marsh including 10 Magnolia, 4 black-and-white, and 2 blackburnian warblers. The highlight was the two male scarlet tanagers that landed close to us. On the water we found four nests and 3 families of Canada geese along with an adult bald eagle and 10 double-crested cormorants.

Scarlet tanager, photo by Kelly Colgan Azar

The three of us checked out Erstad Prairie and Schoeneberg Marsh Waterfowl Production Area, where we found a flock of seven female hooded mergansers, a pair of red-necked grebes, and yellow-headed blackbirds. 

In the county we also added American white pelican, common gallinule, black tern, and Eurasian collared-dove.

Goose Pond in spring is full of life. Photo by Arlene Koziol

It was a very rewarding day to see the results of Madison Audubon Society’s acquisition and restoration efforts. Many birds greatly benefit from the habitat provided.

The Great Wisconsin Birdathon raises funds to support the Bird Protection Fund. Funds raised by the Reckless Wrens are split 50/50 between Madison Audubon and the Bird Protection Fund. (Prior to retirement from the DNR, Sue served on the committee that established the Bird Protection Fund that provides funding for important bird conservation projects. Jim serves on the Great Wisconsin Birdathon planning committee.) If you would like to donate to the Reckless Wrens it is not too late. Ten cents per species would be a donation of $12.20 or you can make a donation of any amount to our team. Thank you for your support!

Written by Mark Martin and Sue Foote-Martin, Goose Pond Sanctuary resident managers, and Jim Shurts, MAS board member and sanctuaries chair

American Redstart

Song sparrow with bands. Photo by David Craig

In his essay “Natural History, Forgotten Science” Aldo Leopold lauds the pioneering citizen science work of banding song sparrows. The woman who decided to put these cellulose anklets on the birds, he says, “knew more about sparrow society, sparrow politics, sparrow economics, and sparrow psychology than anyone had ever learned about any bird.”

Today, advancements in technology have allowed us to go beyond the backyard scope, on a Caribbean flight to the wintering grounds of the songbirds of North America. Tiny transmitters attached to the bird measure day length, and give an accurate estimate of where a bird might overwinter. Analysis of stable carbon isotopes in feathers and nails provides insight into not only the location a bird stayed but also the quality of the habitat, and thus the health of the bird.

American redstart, photo by Becky Matsubara

These techniques have been used in studying American redstarts, and Peter Marra and his lab group have conducted the research that has revealed the inner workings of redstart culture.

First, researchers—going off of observations in the field from Jamaica—tested whether males and females were found in different habitats on the island. Indeed, the redstarts were; females and yearling males inhabited the drier scrub on the island, adult males inhabited the wet mangrove forests.

Studies of these habitat types revealed that the mangrove forest was a steady five course meal compared to the scrub. Insect orders preferred by redstarts were much more abundant in the mangroves, and that food source was much more consistent over the wintering months, whereas the scrub saw productive spikes after rainfall but also nadirs during drought.

Mangrove forest, photo by Arlene Koziol

The question to ask was then, was the habitat preference innate to males and females, or was this the result of competition?

On their overwintering grounds in Jamaica, redstarts are quite territorial. To test the competition theory, researchers conducted a removal experiment where territorial males in the mangrove forest were taken out of that habitat. The vacated habitat was filled within days by females and yearling males. It's as if these birds saw their neighbors' mansion evicted, waited a day for good measure, then quickly occupied the space.

This finding had profound implications for how we understand bird populations. Often, density is used as a proxy for quality of habitat. Yet, in these Jamaican habitats, redstarts were densest in the lower quality scrub habitat, and those despots in the mangrove forests were excluding other birds.

Researchers next asked, if these habitats differ in quality, how do they affect the health of redstarts? During the long overwintering period, from October until April or May, females and yearling males lost mass on average, while males (and the small number of females) in the mangroves maintained or increased body mass.

American redstart, first year male, photo by Kelly Colgan Azar

There's another twist in this fascinating tale, however. Yearling males exhibit delayed plumage maturation. Adult males have glossy black feathers with bright orange on the sides while yearling males and females are more olive gray with a duller yellow. It was found that some yearling males were able to occupy the high quality mangrove habitat, but how and why could this be the case? Well, these birds were shown to have more black pigment and larger black patches in their feathers. In essence, they looked more like the adult birds. Were these birds simply quicker at maturing? It turns out, that during territorial disputes, redstarts will peck out the feathers of the sparring partner. In these young males, picking a fight led their feathers to be pulled out, and these feathers were replaced with more adult-like plumage. These birds were literally earning their stripes through territorial disputes!

This is all very interesting, and has immediate consequences for our understanding of these birds and their overwintering habits, but it gets even more interesting as we head back to breeding grounds in North America to see how overwintering condition affects breeding output.

American redstart, photo by Dan Pancamo Photography

First, the males in good condition from the mangroves are the first to leave the island. Females and yearling males leave later into April and May. Since the females have lower food resources over the course of the winter, they are in rather poor condition during migration, and many of the females in poorest condition see decreased success on breeding grounds. All of this increases the likelihood that females will die. The life cycle of the female helps us to understand the population dynamics in this species—the sex ratio in redstarts skews towards a higher ratio of males. Females might be more likely to die at any point during the life cycle, and the lower number of breeding females may limit the general population of redstarts.

Overall, the condition of the later-arriving male and female redstarts was poorer, and both sexes saw decreased reproductive success on breeding grounds. These studies were among the first to delineate carryover effects from non-breeding grounds, an important finding that  tropical wintering grounds—once thought of as a relaxing vacation for these birds—could limit populations and produce discernible patterns on breeding grounds. It's an amazing story, with one scientific study built upon another, to understand the ecology of this species.

Many questions remain to be answered. Might rising seas due to climate change reduce habitat on islands like Jamaica for redstarts and other neotropical migrants? Will a disruption of weather patterns cause more drought in the Caribbean and decrease populations of insects and thus populations of birds like redstarts? Furthermore, changing leaf out dates in North America have been proven to affect some species and their reproductive success. Might this be the case with the American redstart? Researchers think that the early arriving (healthy) males also find the best insect availability upon arrival. How might these changes in phenology bear out on breeding grounds? Clearly, the conservation and ecology of the American redstart is a complicated and ever-shifting matter. The next time you see a redstart frenetically jumping through an oak tree, you can speculate as to what habitat this redstart spent its winter, and subsequently the overall health of the bird. If it's a yearling male, you might even be able to tell how many fights he's been in.

Written by Drew Harry, Faville Grove Sanctuary land steward

Breeding Bird Atlas II: Year 4

Everyone is glad that spring has finally arrived, including the migrating birds! This is an excellent time to get out for some fresh air, to check out the migrating birds, and to participate in Wisconsin’s largest citizen science project, the Breeding Bird Atlas II. This is the start of year four of the five-year project and there are many opportunities to make observations and memories. 

Arlene Koziol photographed a barred owl family at the Lakeshore Nature Preserve in Madison, which includes three young. The atlas welcomes all photographs. Photo by Arlene Koziol

The first atlas was conducted from 1995–2000 by over 1,600 (mostly) volunteer observers. The information they collected proved to be a landmark tool guiding species management and conservation activities by federal, state, and private natural resource groups. The second, five-year atlas is documenting changes the last two decades. Major partners leading the atlas project are the Wisconsin Society for Ornithology (WSO), the Department of Natural Resources, the Western Great Lakes Bird and Bat Observatory. Madison Audubon Society endorsed the project and is sponsoring the Canada goose. Funds from species that are sponsored are used to hire birders to conduct point counts and to atlas in difficult areas.

The Wisconsin Breeding Bird Altas II is still looking for volunteers this year. Image provided by Wisconsin Society for Ornithology

Kim Kreitinger, former WSO President, said, “The second Atlas project will provide a new snapshot of Wisconsin’s bird community, which will help us address important bird conservation issues in the state. Because the Atlas requires such a massive volunteer effort, it will also help us to elevate public awareness of nature and directly connect Wisconsin’s citizens to conservation.”

In Wisconsin, 1,500 volunteers have submitted almost 95,000 checklists and confirmed 220 species. In Columbia County alone, 129 volunteers have submitted almost 2,000 checklists and confirmed 122 species. The atlas work is conducted by birders that adopt a specific block of land and others that submit random observations. There are 18 priority blocks in Columbia County and an additional 67 blocks. Each block is three by three miles wide.

In Columbia County, we are finding interesting changes in bird populations. Bald eagle and osprey counts are increasing, while other birds like the ruffed grouse and ring-necked pheasant are decreasing. We added common ravens to the list of nesting birds in Columbia County while finding that gray partridges no longer live here.

Bald eagle nests are increasing in Columbia County. Photo by Richard Armstrong

We are looking for common as well as uncommon birds to atlas. In Columbia County some birds of interest include: hooded mergansers; great blue heron rookeries; green herons; turkey vultures; ospreys; Cooper’s hawks; bald eagles; red-tailed hawks; American woodcock; eastern screech, great horned, barred and northern saw-whet owls; eastern whip-poor-wills; chimney swifts; belted kingfishers (nesting cavities); red-headed and pileated woodpeckers; purple martins; brown thrashers; scarlet tanagers; dickcissels; bobolinks; eastern meadowlarks; and orchard orioles.

Four great blue heron on their nest tree. Photo by Richard Armstrong

Northern pintails have only been recorded as “probably nesting” in two of Wisconsin’s 6,800 blocks. Our goal this spring is to confirm pintails nesting for the first time in Wisconsin Atlas II at Goose Pond. At the pond there are two lone pintail pairs and we will be working with volunteers to also confirm nesting for northern shovelers, gadwalls, green-winged teal, and ruddy ducks.

Ruddy duck brood south of Goose Pond. Photo by Mark Martin

All the county coordinators can use additional help. The more eyes and ears we can get out there, the better our Atlas results -- and our ability to conserve birds -- will be. Overall in Columbia County, we are doing very well; however, we need more volunteers to help cover priority blocks, report incidental observations, help with special surveys for species like whip-poor-wills, and canoe waterways. (Sounds like a tough job, doesn't it?)

You don’t have to be an expert birder to be part of the atlas! All you need is to be a careful observer, learn the data collection and reporting procedures, and then go out and enjoy observing birds. Those wanting to learn more should visit the Atlas webpage (wsobirds.org/atlas) and the eBird Atlas webpage (ebird.org/content/atlaswi).

If you would like to help in Columbia County you can contact Mark and Sue at 608-333-9645 or goosep@madisonaudubon.org.   

 Hopefully you will have many memorable atlas sightings. Some of our favorite sightings and memories are locating the southern-most raven nest in the state, seeing an osprey nest on the tall lights at the Pardeeville High School football field, a landowner with 160 nesting pairs of purple martins, seeing nesting red-headed and pileated woodpeckers, and photographing a vulture nest in a large silver maple nine feet high.

These ospreys don't mind the Friday Night Lights at Pardeeville High School. Photo by Mark Martin

We had 9-foot-high hopes for this turkey vulture nest found during a WI Breeding Bird Atlas II survey. Photo by Mark Martin

Written by Mark Martin and Sue Foote-Martin, Goose Pond Sanctuary resident managers and Atlas Coordinators for Columbia County

Red-headed Woodpecker

One of the most dazzling birds in Wisconsin simultaneously occurs in one of the most enchanting natural communities. The red-headed woodpecker in an oak savanna is a sight to behold.

Not to be confused with red-bellied woodpeckers, which also have a red head, the red-headed woodpecker has a sparkling crimson head, neck, and face while red-bellied woodpeckers only have red on the back of the head with gray faces and throats.

You might notice the red-headed woodpecker in flight among oaks trees with an open understory, and you can't miss its jet black fathers, checkered with pure white on parts of the wing, tail, and the entirety of the breast.

Red-headed woodpecker, photo by Arlene Koziol

A purposeful bird, this woodpecker's flight takes a more direct path than other woodpeckers, and you'll typically see red-headed's flying rather straight routes from oak to oak and dead snag to dead snag. It's a bird that, when observed, seems to have no indecision.

An area of varied decision-making comes with the bird's diet, which is omnivorous and among the most diverse of all woodpecker diets. Insects make up a large proportion of prey items during summer, and red-headed woodpeckers are experts at catching insects mid-air. They will also consume and cache acorns, which are supplemented by fruits, nuts, seeds, mice, eggs, and even snakes and lizards.

Red-headed woodpecker, photo by Arlene Koziol

Moreover, in studies of woodpecker habitat partitioning, red-headed woodpeckers were found to forage the full range of a dead snag, from top to bottom, and showed no preference for small or large diameter snags, whereas a bird like the downy woodpecker will forage on small diameter trees at restricted ranges.

Hardy enough to spend the winter in Wisconsin, a few red-headed woodpeckers remain each year, but many will migrate slightly south of the snow line. A study in Missouri found that high mast production of acorns, walnuts, and hickories was related to high overwintering numbers of red-headed woodpeckers; it's likely that those birds overwintering in Wisconsin found an excellent crop of acorns.

Red-headed woodpecker and nestling, photo by Arlene Koziol

Additionally, the birds lay 4 to 7 eggs, with some laying up to ten, and red-headed woodpeckers will often raise a second brood. 

With its range of adaptations, one might expect the red-headed woodpecker to be common throughout the state. However, the bird is a Wisconsin species of Special Concern, and the North American population has been cut in half over the past few decades, while the Wisconsin population has declined 60-70%.

It's impossible to pin down an exact cause of this mysterious decline, but let's use Faville Grove Sanctuary as an example of how these populations have declined (and how they can recover).

The Lake Mills Ledge has been restored to an oak savanna with scattered, large diameter bur and white oak trees. After pasturing ceased decades ago—and due to fire suppresion—buckthorn and honeysuckle invaded the understory, and black cherries, elms, and boxelders profused between and among the oak trees. This led to canopy closure, and the restricted space didn't allow red-headed woodpeckers to catch insects or survey from perches.

It's also possible that dead trees and snags were removed from this small forested stand and used for firewood, which would have effectively eliminated nesting cavity habitat for the woodpeckers. Prior to habitat acquisition and restoration, the Lake Mills Ledge was a small island in an agriculturally dominated landscape—where European starlings were frequent, and likely attacked any red-headed woodpeckers inspecting a cavity.

Spring in a Wisconsin oak savanna, photo by Joshua Mayer

The effect of restoration on this small savanna has had tremendous positive effects on the red-headed woodpeckers. Clearing of invasive brush and trees has restored the savanna structure, and provides the vistas that red-headed woodpeckers use to pick out prey items. Girdling (removing the cambium and disrupting the flow of nutrients, which kills the tree) of select trees, including a clump of large diameter black willow, has allowed for the desirable characteristics that red-headed woodpeckers look for in a home: large diameter trees flushed of bark, clusters of dead snags, and a high density of dead limbs, especially limbs close to the ground. Lastly, the restoration to native plant communities in the surrounding landscape has made it less likely that starlings will attempt to disrupt nesting activities.

This habitat restoration has proven beneficial to other species as well. Last year we found breeding bluebirds, northern flickers, and downy woodpeckers among the snags.

Red-headed woodpeckers are not an area-sensitive species, meaning they don't need large tracts of habitat for breeding success. Rather, a few dead trees mixed among some living oaks will do just fine. Thus, there is opportunity for private landowners and urban areas to restore populations of red-headed woodpeckers. The solutions prove to be rather simple: cutting invasive brush, and thinning and girldling trees. While the bird's decline remains mysterious, its recovery is less so.

Written by Drew Harry, Faville Grove Sanctuary land steward