Canvasback

Species includes (from Left-Right): Male canvasback, female redhead, male redhead, and female canvasback was taken last spring at Schoeneberg Marsh. Photography by Richard Armstrong.

Species includes (from Left-Right): Male canvasback, female redhead, male redhead, and female canvasback was taken last spring at Schoeneberg Marsh.

Photography by Richard Armstrong.

H. Albert Hochbaum, who studied under Aldo Leopold, in his book The Canvasback on a Prairie Marsh described a flock of ducks “Swinging now high, now low they course the ice field for many minutes until finally, breasting the wind that carried them north, they alight with a swish in a dark pool at the edge of the ice.  They rest nervously, heads up and alert, white-backed forms rocking in the water like chunks of ice.  The “Cans” are back!

The scene at Goose Pond on March 14th reminded us of the above passage where there was about one-quarter acre of open water.  It was a treat to see a small flock of 15 cans circle and land.   March 14th was a wintery day, 340 tundra swans and 220 greater white-fronted geese were hunkered down trying to conserve energy while 96 canvasbacks were swimming in the open water.  Luckily for the waterfowl, the pond was completely open three days later.   With a top-end speed of 70 mph, canvasbacks are North America's fastest duck and also the largest duck. 

Canvasback numbers stayed fairly consistent for the next week and ranged from 80 to 100.  On some days, cans were near the road and provided birders and wildlife photographers with good viewing opportunities.  It was unusual not to see any redheads on the pond.  The males of these diving ducks with red heads can be distinguished apart by the canvasback’s white body and sloping forehead compared to the redhead’s gray body and head similar to other ducks.

Novice bird watchers could easily observe that the sex ratio was heavily skewed to males and that the cans were establishing pair bonds on migration.   Predation on females during the nesting season helps contribute to the imbalanced sex ratio.  

Photography by Richard Armstrong,  taken recently at Goose Pond.

Photography by Richard Armstrong,  taken recently at Goose Pond.

In the mid 1950s, the canvasback population numbered around 600,000.    In the 1980’s and early 90’s, there were some years when cans numbered around 400,000 and the canvasback season was closed.   Loss of breeding and wintering habitat and lead poisoning due to ingestion of spent shot while feeding lead to the low numbers.  When lead shot was replaced with steel and water returned to the prairie pothole region of the Dakotas and Canada their numbers increased.  In the past few years their population has been around 750,000 individuals and there is a hunting season with a two bird daily limit.  The place to see tens of thousands of canvasbacks in fall is the Mississippi River in late October and early November.

Canvasbacks migrating through Wisconsin are probably from wintering grounds in the mid-Atlantic and the Lower Mississippi Valley.  Historically, the Chesapeake Bay wintered the majority of canvasbacks, but with the recent loss of submerged aquatic vegetation in the bay, their range has shifted south towards the Lower Mississippi Valley.  Brackish estuarine bays and marshes with abundant submerged aquatic vegetation and invertebrates are ideal wintering habitat for canvasbacks.  At Goose Pond the canvasbacks, redheads and tundra swans feed on the arrowheads (duck potato) tubers.  Often the cans and redheads feed close to the swan hoping they can snatch a tuber or two from the swans.

Photography by Arlene Koziol, taken at Goose Pond

Photography by Arlene Koziol, taken at Goose Pond

Someone asked us recently if canvasbacks nest in Wisconsin.  In the first breeding bird atlas from 1995 -2000 there was a possible breeding record of canvasbacks from Rush Lake in Winnebago County.  Rush Lake is Wisconsin’s premier prairie wetland.  Sam Robbins wrote in Wisconsin Birdlife that canvasbacks seldom breed in Wisconsin.  Robbins found records of canvasbacks nesting in six counties from 1892 to the last recorded nesting in 1976, including a 1927 record of canvasbacks nesting in Madison.

We hope you can visit Goose Pond this spring and hopefully see the “King of Ducks”.

By Mark and Sue Foote-Martin, Goose Pond Sanctuary Managers

Northern Saw-whet Owl

Photography Credits: Drew Harry

Photography Credits: Drew Harry

“At night in the fall there are probably these little owls about the size of a soda can that weigh as much as a robin flying over [your] house and we're completely oblivious to it.” Scott Weidensaul in an interview with Terry Gross for Fresh Air, Oct. 20 2015.  You can find the whole fascinating interview here.

That little soda can is the Northern Saw-whet Owl, a secretive Wisconsin breeder usually heard, rarely seen.  If seen you'll notice their small size, yellow eyes, and dark beak. They may be confused with short-eared owls but can be distinguished by being much smaller and having reddish facial disks without a dark border. You also might wonder, why saw-whet? The sound of a saw on a whetsone resembles the owl's incessant call, which Scott Weidensaul called “psychosis inducing” after spending nights netting saw-whet owls by attracting them with 110 decibel calls.  You might also wonder what a whetstone is—it's a fine stone used for sharpening tools. 

Weidensaul annually nets about 500 saw-whet owls in migration at the Ned Smith Center in Pennsylvania. The first Wisconsin Breeding Bird Atlas reported 73 records of saw-whet owls over a five year period.  So far, birders for the second Wisconsin Atlas have seen only a handful of breeding saw-whet owls throughout the state, mostly in northern counties.  There may be a very small number of saw-whet owls in the Wisconsin, with larger numbers moving through during migration, or there may be a bias in recognizing the species.  Atlases and Christmas Bird Counts don't do a great job of finding this nocturnal species.

Saw-whet Owls prefer dense woodland or occasionally savanna, often conifer or mixed forest. Obligate cavity nesters, the birds need dead trees for their survival.  They will readily take to nest boxes, however. 

The owls will overwinter in southern Wisconsin and feed on small mammals like deer mice, white-footed mice, and chipmunks. With young, females incubate and brood, while males provide almost all of the food.  Males will continue to provide food after fledgling.

Photography Credits: Drew Harry

Photography Credits: Drew Harry

Saw-whet Owls exhibit a number of cool traits, such as controlling their head in order to keep their eyes on prey while executing aerial maneuvers. The owls also have asymmetrical facial disks, which allows them to exact stunning hunting intuition. An interesting tidbit is that you can see the eye of a Saw-whet Owl through its ear hole.

At Faville Grove, we found a perished Saw-whet Owl a few weeks ago. Upon closer inspection, the eye was visible behind the bird's facial disk! This interesting bird also had a mouse in its talons, and the specimen was a random way to discover that the furtive birds use the sanctuary over winter.

This March, you'd be lucky to see a Saw-whet Owl near the conifer planting along Faville Woods. The owls tolerate close approach without flushing, so if you stumble within inches of a saw-whet, look for the back of its eye through its ear!

Written by Drew Harry, Faville Grove Land Steward

Mute Swans

In the past two weeks the ice melted off Goose Pond, and the swans began to return.  Tundra swans migrate in massive flocks, and usually number in the hundreds on Goose Pond.  Occasionally there are trumpeter swans on the pond, usually in pairs, or small family groups.  An unusual sight this week, was an exotic mingling with the tundra swans on the pond.  Richard Armstrong, a wildlife photographer and Madison Audubon supporter, was taking photos of the early migrants, when he noticed the tell-tale orange bill of the mute swan.

Photograph by Richard Armstrong, MAS member

Photograph by Richard Armstrong, MAS member

Besides the orange bill, mute swans can be distinguished from tundra swans and trumpeter swans by the black, fleshy knob at the top of the bill.  They tend to be a little smaller than our native swans.  They carry their necks in a distinctive “S” shape while swimming, usually with the bill pointed down. 

The mute swan is native to Eurasia.  It has been present in North America since the late 19th century when it was brought here to adorn ponds in urban parks.  Some birds escaped or were released from captivity.  The bird escaped and due to its long life and urban adaptability, quickly established a large and growing population.  Estimates based on aerial surveys over the Great Lakes, and Christmas Bird Counts, show that the North American mute swan population, around 18,000 in 1997, increases by 10% every year.  A mute swan may live up to 18 years in the wild, and produces a brood with an average of 5 cygnets.

Photography Credits: Larry Bond

Photography Credits: Larry Bond

Mute swans congregate in large flocks.  They remain year-round in the coastal Great Lakes wetlands region where open water can be found even in winter.  They are big eaters, consuming up to 8 pounds of aquatic vegetation a day.  During spring when resources are most limited, mute swans can strip a pond of its vegetation beyond the ability to regenerate before our native waterfowl have even returned.  Overgrazing is sped up by the bird’s habit of raking and paddling the substrate while feeding.  Even vegetation that isn’t eaten is killed by this habit, and turbidity can increase enough to prevent regeneration.  This puts pressure on diving ducks such as canvasbacks, and scaups that rely on the same aquatic vegetation. 

Mute swans are exceptionally aggressive and territorial.  They can displace other waterfowl including trumpeter swans from their nesting areas, and have been known to attack or even kill adult or juvenile ducks, geese, and other wetland birds.  Trumpeter swans are still a species of concern though they were taken off the Wisconsin endangered species list in 2009.  Mute swans are also known to attack humans.  Mute swan-human interactions are more common because mute swans are often found in urban wetlands, and because their beauty and reputation as the symbol of love may fool people into believing they are gentle creatures.  A few years ago, a man in Ohio ventured too close to a nesting pair, and was attacked by the cob (male); he suffered a heart attack and died.  Do not be fooled, and remember to respect all wildlife!

Many states have a mute swan management plan with a goal of achieving zero reproduction within state boundaries.  Wisconsin’s DNR adopted such a plan in 1997.  The primary method used to reduce mute swan numbers was through egg addling.  Within ten years, the Wisconsin mute swan flock was greatly reduced.  Michigan’s DNR decided not to manage their mute swans, and they now have a population of 4,000-5,000.  On occasion, small flocks of mute swans are found off the tip of Door County where Michigan swans move along the Grand Traverse Islands, connecting Michigan and Wisconsin.  Mute swans are rare at Goose Pond, however, this spring, bird-watchers may be able to find the trifecta of swan species.

Written by Maddie Dumas, Goose Pond Land Steward & Mark and Sue Foote-Martin, Goose Pond Sanctuary Managers

Hooded Mergansers

Photography by Rick Leche

Photography by Rick Leche

Hooded mergansers are rather common in forested river, lake, and wetland areas of Wisconsin. Restricted to North America, “hoodies” nest in tree cavities and wood duck boxes. The birds are more common in the northern part of Wisconsin since the southern part of the state has fewer areas of forest cover surrounding water bodies.

With a broad diet, hooded mergansers can be seen diving and fishing, pulling crayfish and frogs or dragging macrophytes. One personable merganser has gained considerable fame in birding circles this winter at Frame Park in Waukesha, often photogenically gulping down crayfish just feet from shore. You can find its incredible photos on the Birding Wisconsin Facebook page.

Hooded mergansers will lay eggs in the nests of wood ducks, but in a tit-for-tat, wood ducks often lay eggs in the nests of hooded mergansers. Like wood ducks, hatched hoodies will jump from the nest (just one day after hatching), sometimes falling/flying over fifty feet. Upon landing, the young will follow the female to a water source where they are immediately able to dive and feed short distances.

Photography by Tom Benson

Photography by Tom Benson

Here at Faville Grove, you can find hooded mergansers migrating throughout the sanctuary. Open water scrapes and shallow ponds are excellent spots to find these birds. If you do find a hoodie, delight in its search for food as it probes the water and disappears for long periods, only to pop up with a wetland treat.

Written by Drew Harry, Faville Grove Land Steward

Dark-eyed Juncos

Dark-eyed juncos are a well-known winter bird in the upper Midwest, and one of the most abundant birds of the non-breeding season.  Perhaps their attractive dark blue, or “slate-colored” plumage makes them a welcome sight at your winter bird feeders.  They prefer to eat from the ground, and in winter they will forage for grass seeds or insects from snow-free patches of ground along roadsides, or scrounge seeds knocked from backyard feeders.  Living in Canada during the summer, they disperse throughout the United States in winter.  They arrive in Wisconsin around November, and are usually the most abundant bird in our Christmas Bird Counts.

Dark-eyed Junco, photography by Maddie Dumas

Dark-eyed Junco, photography by Maddie Dumas

This year, of the 1,800 teams that participated in the North American Christmas Bird Count (CBC), 1,600 teams found slate-colored dark-eyed juncos.  The team with the highest number of slate-colored dark-eyed juncos was Pardeeville, WI!  The second place team, from Pennsylvania, found 3,501 juncos.  In 18 states, 2 Canadian provinces and the District of Columbia, there were 97 counts that found over 1,000 juncos.  Sixteen of these 97 high counts occurred in Wisconsin, but they ranged from the west coast, California and Washington, to the Midwest, Kansas and Oklahoma, to the east coast Massachusetts and Connecticut.  Usually the more participants, the more birds, so National Audubon Society also totals birds per party hour.  The top five teams in juncos per party hour were all from Wisconsin.  Blanchardville (3,289; 100 per party hour), Richland Center (2,706; 85 per party hour), Bridgeport (2,530; 79 per party hour); Pardeeville (4,688; 76 per party hour), and Brodhead (2,666; 73 per party hour).

Dave Willard, a veteran birder who grew up in Madison led the Blanchadville count.  Willard mentioned that juncos were extremely abundant during the Blanchardville CBC on December 19th.  While the team of 13 worked 33 party hours and ended up with an impressive 3,289 juncos, it is likely that with more party members, many more birds could have been counted.  A similar observation was made by Mark, Sue, Maddie and their fellow teammates in the Pardeeville CBC.  We all remarked on the large number of juncos found along roadsides, however, it was not until the results were tabulated that we learned of the record high count.  The Pardeeville CBC, coordinated by Paul and Glenna Schwalbe, had 21 counters, and worked for 62 party hours.

Dark-eyed Junco, photography by Kelly Colgan Azar

Dark-eyed Junco, photography by Kelly Colgan Azar

In contrast, National Audubon Society’s Great Backyard Bird Count (GBBC) that ran from February 17-20th told a very different story about the distribution of dark-eyed juncos in Wisconsin.  The unusually warm weather the upper Midwest has been experiencing for the last week has led to fewer birds at feeders, and fewer dark-eyed juncos in general.  At the Kampen Road residence, the February 17th GBBC turned up six juncos in the yard, with an additional six more in the food plot.  The Prairie Lane residence GBBC on February 20th counted no juncos at all.  Results are still being reported for the GBBC, but distribution maps show the largest concentrations of slate-colored dark-eyed juncos along the northeastern coast from northern North Carolina up through New England, and around the southern tip of Lake Michigan near the Chicago area, with scattered populations throughout the U.S., particularly around larger cities.  The southernmost junco reported was from Austin, TX, and the northernmost was found in southern Alaska.  It will be interesting to continue to compare the results of the 2016 CBC, with the 2017 GBBC, to see how the numbers of juncos in Wisconsin shift in this two-month period in the winter, and to consider how unusual winter weather affects our winter birds.  Meanwhile, enjoy the juncos while they are here!

Written by Mark and Sue Foote-Martin, Goose Pond Sanctuary Managers & Maddie Dumas, Goose Pond Land Steward