Tennessee Warbler

The Tennessee Warbler flies through a Midwestern spring, making itself known with its surprisingly loud “tip tip tip tip tip sippp sippp sippppp ti ti ti ti ti” song. A flock of dozens of these warblers will soon make a birder search for other species, and the full helping of the Tennessee Warbler is soon forgotten. On these dazzling spring mornings, the Tennessee Warbler is often but a overabundant appetizer, say cheese and crackers, to the buffet of warblers to be had. However, as May wanes, so does this warbler, and soon it is gone, and often unseen, until spring returns.

Tennessee warbler, photo by Jeff Bryant

However, right now marks an excellent time to catch that Tennessee Warbler once more before it makes its way south to its namesake Volunteer State (where it only migrates through) and even further south to South America.

Once in South America, this warbler will often reside in shade-grown coffee plantations, where abundant flowering trees provide plentiful insects and nectar. This habit led ornithologist Alexander Skutch to suggest “coffee warbler” as an alternative to the misnomer of Tenessee Warbler.

Shade-grown coffee plantation, photo by Marshal Hedin

In reality, these are birds of the high northern latitudes, breeding in openings of the boreal forest. Nests are constructed in hummocks of sphagnum and sedges, and because the spruce tree is a characteristic boreal tree, a favorite menu item of the Tennessee Warbler is the spruce budworm, which can break out and defoliate forests of spruce.

Some forestry operations in Canada will spray entire forests with insecticide in order to inhibit the spruce budworm, and more recent advances have led to lepidoptera-specific insecticides. Researchers in Canada have sought to understand whether this spraying affects the Tennessee Warbler, and have discovered that the females will alter feeding behavior in sprayed areas, and as a result will spend less time tending to their brood. However, no negative effects were found on the brood survival. Whether the long-term effects of this spraying will reduce populations of Tennessee Warblers remains to be seen, but their population is stable for now.

Tennessee warbler, photo by Russ Wigh

Again, it’s very rare for the bird to breed in Wisconsin; in the second Breeding Bird Atlas, birders only coded two Tennessee Warblers as “probable” for the entire state of Wisconsin. But these warblers are abundant for the moment, and you might find them in woodlands throughout the state as they make their way south, hopefully to a nice sustainable coffee plantation.

Written by Drew Harry, Faville Grove Sanctuary land steward

Barn Swallow

I remember mowing my great grandmother’s lawn as a kid. Located in the flat country of the Lake Michigan coastal plain, this old farmstead with sideways chicken coops and crumbling barns made for interesting mowing, especially due to dive bombing swallows. Years later, I would discover that the railroad abutting the old farmstead still held a piece of mesic prairie—one of the most endangered and fragmented plant communities in the state of Wisconsin. Little did I know that six species of swallows call Wisconsin home, or that these local swallows were caring for nearby nests.

Barn swallow photo by Kelly Colgan Azar

No, as I mowed as a kid I knew none of this, I merely risked life and limb each time I pulled out the riding mower, skirting rectangular patterns around the outbuildings. I feared the day a swallow would drill my face; they never did.

Today, I see daily the barn swallow nest under the deck on Prairie Lane, and it’s a happy reunion each year when they return from South America and brilliantly grace spring with their rich orange undersides. Of course, this acquaintance has run into some neighborly conflict.

Barn swallow chicks, photo by Whitney H

I clean up the droppings from the chicks once they’re big enough to move around the nest, while on the other side of things, the parents are disturbed off the nest every time we come and go from the house. As a mark in my favor, one barn swallow a few years ago flew behind me through the open screen door and crashed about the inside of the house, leaving behind some feces. As a mark against me, I occasionally stick my camera, with the flash on, into the nest to see how many eggs and chicks occupy it—an obtrusive gesture, especially when chicks expecting a meal are disappointed to find bright lights and an iPhone.  

Barn swallow fledglings, photo by Mick Thompson

All in all, I get along with my barn swallow neighbors, and they are beautiful to watch in flight while they pick off dragonflies and the like. Currently, these birds are particularly abundant because recently fledged young are maneuvering their way around old farmsteads in ways only a barn swallow can. The pair under my deck already fledged four young, and the second brood is now hatched and getting ready to fledge. This species needs man-made structures to nest, or will otherwise nest on cliffs and ledges. Thus, the barn swallow exists in a secure state and is nearly worldwide in distribution.

In fact, recent observations have confirmed that barn swallows, in an unlikely move, have started nesting on overwintering grounds. Traditionally, their breeding range has included most of the northern latitudes while wintering grounds included most of the southern hemisphere. In another twist, during winter, these breeding Argentinian barn swallows migrate north for winter. The exact reason for this shift is unknown, but the barn swallow, already a bird happy with human innovations, has turned its own innovation by completely changing its migratory patterns.

Barn swallow range map, provided by Cornell Lab of Ornithology, https://www.allaboutbirds.org/guide/Barn_Swallow/maps-range

You can find barn swallows around most of the buildings around Faville Grove Sanctuary; you can’t miss them.

Written by Drew Harry, Faville Grove Sanctuary land steward

Cover photo by USFWS Midwest Region

Rusty patched bumble bee

When the phrase “endangered species” is used, large animals like Asian elephants, whooping cranes, black footed ferrets, and Bornean orangutans most frequently come to mind. Consider the logos for major wildlife conservation organizations. Again, these species are usually large animals, frequently mammalian, and high on the food chain. While some of the Earth’s mammal species are declining at alarming rates, other less charismatic groups with critical ecosystem roles such as fish, mollusks, and plants make up a far larger proportion of listed endangered species. At Goose Pond Sanctuary, we host three endangered insects including the silphium borer moth, red-tailed leaf hoppers, and as of August 3, the rusty patched bumblebee.

Provided by International Union for Conservation of Nature

The rusty patched bumble bee was the first bee listed as endangered in the continental United States when it was official added to the federal endangered species list in 2017. In the 1900’s, the rusty patch was formerly abundant across the Midwest, eastern US, and southeastern Canada. Major contributors to declines in rusty patch populations are habitat loss, pesticide use, and pathogens. Recent surveys show that the range of the rusty patch has decreased dramatically over the last decade, and their overall population has decreased by at least 87%. This is one of the reasons that we were ecstatic when Taylor Tai, a graduate student from UW Madison whose focus is on bumble bee habitat requirements, successfully captured and identified a rusty patch bumble bee at Goose Pond during a tour. 

Participants of our August 3, 2019 bumble bee walk field trip at Goose Pond Sanctuary got to see first-hand the rusty-patched bumble bee! Photo by Graham Steinhauer

Rusty patch bumble bees can be found in a variety of habitats including open woodlands, backyard gardens, and prairies. They have short tongues relative to other bumble bees and therefore prefer open flowers. Sun flowers, bee balm, and goldenrods are some of their favorites. Sunflowers at the Goose Pond food plot just began to bloom, and they’re covered in bumble bees and butterflies. The rusty patch is known to pollinate 65 genera of plants including some species that are highly beneficial to humans like cherries, apples, cranberries, and alfalfa. 

Sunflowers provide awesome fodder for pollinators. Photo by Mark Martin

Prior to the discovery of a rusty patch bumblebee this summer, eight of the seventeen Wisconsin bumble bee species have been observed at Goose Pond Sanctuary. Most bumble bee colonies are composed of a single queen along with 30 to 200 female workers. Nests are usually located a foot or two below the soil surface in abandoned rodent holes or in insulated above ground cavities. Males do not inhabit the colony. Bumble bees and other pollinators need high quality nectar plants throughout the season which is why prairies with high plant diversity and variable bloom times provide excellent pollinator habitat. 

On August 2, Eva Lewandows and Terrell Hyde, both conservation biologists from the WI DNR’s Bureau of Natural Heritage Conservation, visited Goose Pond in search of bumble bees. Their objective was to test survey methods and establish protocol for citizen volunteers assisting with the Wisconsin Bumble Bee Brigade. If you want to learn bumble bee life history, how to identify them, or how you can help, visit the Wisconsin Bumble Bee Brigade home page. You can read about Wisconsin bumble bee species, explore datasets, or submit your own observations.

Bee balm are in full bloom at Goose Pond Sanctuary. Photo by Arlene Koziol

Our rusty patched bumble bee was found nectaring on bee balm (also referred to as bergamot or Monarda fistulosa) in the Lapinski–Kitze Prairie. Now is an excellent time to view bumblebees at Goose Pond. All you need is short range binoculars or better yet a camera with a zoom lens. The best places to park are at Lapinski–Kitze Prairie off of Goose Pond Road, and the Land Managers’ residence (W7503 Kampen Road) which is adjacent to our food plot. These insects are large and technically can sting, but they’re some of the fuzziest and friendliest critters out there. Throughout all of her time capturing thousands of bumblebees in pursuit of research, Taylor Tai has not been stung a single time. 

Written by Graham Steinhauer, Goose Pond Sanctuary land steward

Cover photo by USFWS Midwest Region

Field Sparrow

For a field sparrow, no place can quite compare to dry shrubby grasslands with a sprinkling of trees.  One of North America’s smallest sparrows insists upon upland thickets where gray dogwood, raspberry, and invasive honeysuckle and mulberry thrive in an unburned patchwork of prairie. A bouncing song—most resembling in rhythm a dropped ping-pong ball—eventually reaches a peak from a slow tweet to a rapid crescendo, frenziedly declaring its domain of little bluestem, dogwood, and oaks.

Field sparrows are common enough to be easy to find, yet distinctive in their habitat preferences so that one can often determine, simply by walking around and passively absorbing the structure of the vegetation, whether field sparrows might flock to a particular site.  Yet even before an analysis of the vegetation concludes, field sparrows often make themselves known with that ping-pong song.

Field sparrow pair, photo by Drew Harry

My closest encounter with a field sparrow came a few years ago, when I was walking through the best spot for field sparrows in Faville Grove Sanctuary, just east of North Shore Road, where this year I recorded over twenty singing birds on a June morning. On this afternoon a few years back, a pair of sparrows flew right at me. I expected them to fly off course and avoid me, but these sparrows landed on vegetation just inches from me. For a split second, I felt flattered, and befriended. It was as if I had become Snow White, and these birds were to follow my every move.  A veering Cooper’s Hawk quickly dispelled my Disney fable, and confirmed a pair of very smart field sparrows; flying at the top predator to avoid a lesser one.

Nesting in open areas across most of Wisconsin, field sparrows are most abundant in the southern and western parts of the state, and less frequent in the more heavily forested areas of northern Wisconsin. Openings of most kinds make good field sparrow habitat, so long as the ground is dry and there are enough shrubby structural components to make good breeding habitat. Over the course of the summer, field sparrow nests reach taller and taller heights. At the beginning of the nesting season, the birds will often nest on the ground, however, if a second brood is attempted, the birds will often build nests in shrubs and trees, especially once the foliage has filled out.

Field sparrow habitat, photo by Drew Harry

Upon hatching, researchers in Washington state have found that field sparrow parents raise their young with increasing care as the season progresses. As the chicks mature, the parents will make more and more visits to the nest (most often with food). This makes sense, as the chicks are growing and need more frequent feedings. Furthermore, as the brood size increases, so does the number of visits per minute by the adults.

While all of this may seem rote, it can have interesting applications in the field. For instance, seeing a field sparrow making frequent trips to a probable nest site will likely mean that the chicks are far along and close to fledgling. Additionally, if one saw this behavior today, in early August, it’s likely that the nest will be located in a higher location, possibly a tree. So not only could you estimate the chick’s age, you could also point yourself in the right direction of the nest.

On June 15th of this year, I found a field sparrow nest with four eggs, tucked neatly into a small gray dogwood bush. This nest was located where we might predict given the time of year, based on how close to the ground it was and the relatively sparse vegetation surrounding the nest.

Beyond nesting, field sparrows have developed an interesting trick to produce more offspring.  Male field sparrows will often sing at night, and researchers sought to understand why a mostly diurnal bird might belt out song in the middle of the night. In fact, these birds were meeting extra-pair mates. Females responded to these songs mostly when they were reproductively ready and fertile. Wrapped in the dim light of the strawberry moon, field sparrows break their largely monogamous ways.

You can find field sparrows throughout Faville Grove Sanctuary, though the best spot to see the birds is east of North Shore Road. Arriving in early April and leaving sometime in October, these birds actually grace the landscape for a majority of the year with their white eye ring and distinctive pink bills. Right now you might be able to find recently fledged young, perhaps a second brood, foraging through shrublands and brush.

Written by Drew Harry, Faville Grove Sanctuary land steward

American White Pelican

If I were a bird, I might choose to be an American white pelican. One of North America's largest flying birds with a wingspan up to 9 feet and weighing up to 30 pounds, the white pelican strikingly floats through the skies at Faville Grove on warm summer days, riding thermals above the Crawfish River. If the American white pelican were a drink, it might be a piña colada—like the pelican in Wisconsin, this festive white drink is seen only in summer; is tipped with a cute umbrella, not unlike the jovial horny knob that adorns breeding male pelicans. In addition, you wouldn't dare have more than one piña colada for fear of overdoing it, and pelicans around Faville Grove exhibit similar constraint, floating by lazily, rocking through the sky and showing off their black wing tips, only to evaporate minutes later, their white bodies fizzling into the hazy sky. This week we saw 150-200 pelicans flying over one of the new restorations...it was enthralling to watch the birds disappear as they floated toward the sun, then flash their white wings in a reflective burst.

Photo by Arlene Koziol

White Pelicans nest in colonies, and are almost always found together in groups—called a pod, pouch, squadron, brief, or scoop. The communal nature of the birds continues as they hunt. On rivers, lakes, and ponds, white pelicans will circle together and gradually enclose this circle, until the minnows they have been chasing are contained in a frenzied cloud and the pelicans can feast on this buffet. In Wisconsin, the most important fish in the diet of pelicans includes gizzard shad and emerald shiners.

Their high protein diet of fish likely allows these birds to reach such enormous sizes, though they won't typically take fish longer than half the length of their beak and minnows are the most common prey item. Unlike the brown pelican, which can be seen along coastal areas of North America diving for prey, the American white pelican only reaches down and scoops just below the surface, and thus the birds use shallow water to their advantage. It's also a myth that pelicans store fish in their pouch on their beak; rather, this is used when they regurgitate fish they've eaten and feed it to their young.

Photo by Arlene Koziol

In studies of pelican activity budgets on wintering grounds, it was found that white pelicans on lakes and rivers spent about 28% of their day fishing and 72% loafing, making a work day just under 7 hours with no added time for meals. Other free-loading pelicans overwintering in the south have discovered catfish aquaculture farms, and these birds were found to spend 4% of their day fishing and 96% loafing, for a work day of just under an hour!

The pelican was a rare sight in Wisconsin for most of the 20th century, and what a delight it is to have this bird back in the state. Breeding in Horicon Marsh and Green Bay since the mid 1990's, the birds we see likely range from Horicon for daily foraging trips to ponds, lakes, and streams. They're also common along the Mississippi River valley.

The biggest causes of mortality for pelicans are being shot, flying into power lines, and getting trapped on fishing line. Traditional breeding grounds are centered on the prairie pothole region of the Midwest and Canada, and damage occurred to the population throughout the 20th century with the continued drainage of wetlands and the advent of DDT. Since the banning of DDT and other environmental regulations, the American white pelican has slowly rebounded continent-wide.

Photo by Arlene Koziol

Breeding birds find islands within wetlands or rivers and place a nest on the ground, usually a few bill lengths from neighboring birds to avoid being pecked. The breeding birds are quite sensitive to human disturbance, and thus remote areas far from human disturbance are common nesting sites. Lacking a brood patch (the patch of bare skin that forms on many birds while they incubate), the pelicans instead incubate with their feet.

It never fails to amuse me when I point out pelicans in the sky, and someone responds “we have pelicans here?” Indeed we do, and how fun it is to watch them forage through the ponds of southern Wisconsin; how fun it would be to loaf as a pelican does.

Written by Drew Harry, Faville Grove Sanctuary land steward

Cover photo Photo by Arlene Koziol