Walter Piper

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If aliens landed on Earth’s surface to investigate its life forms, they would be puzzled by the coexistence of common loons and humans. True, loons spend almost their entire lives on the water, where they are relatively free of dangers from humans and other terrestrial vertebrates. But loons require solid ground for nesting, safe “nurseries” for rearing their chicks, and abundant food to keep themselves and their chicks alive. How, then, can loon populations persist along the southern periphery of the species range, where humans and human recreation threaten all three basic requirements?

The ability of loons to thrive in regions of intense human building and recreation vexed me for several years in the 1990s, when I first began my long-term loon research. I could see that most people venerated loons and took pains to protect them. But the sheer abundance of humans surrounding, approaching, and fishing near adults and chicks during the spring and summer made the tasks of hatching young and rearing them to adulthood seem daunting. How did loons manage to raise any young in the northern U.S. and southern Canada?

I cannot answer this question completely. I am still amazed at the abilities of adults and chicks on busy lakes to dodge motorboats and jetskis as well as they do. And it continues to surprise me when adults fledge chicks from small lakes where food seems limited. However, detailed study of loons’ nesting patterns allowed me to solve one riddle: how loons enjoy high nesting success despite intensive shoreline development.

One would think that shorelines are essential to nesting loons. Loons have to nest along shorelines, right? And humans build summer homes along shorelines too. So loons and humans would seem to be direct competitors for shoreline habitat. But it is not so. Why not?

The answer is deceptively simple. Well-drained “upland” shorelines provide the best sites for building lakeside homes. Upland sites are free of boggy or marshy vegetation. At the same time, upland shorelines provide poor nesting habitat for loons. Most loon eggs placed on upland shorelines end up in bellies of raccoons that take advantage of the comfortable footing they provide to look for easy meals. Experienced male loons learn to avoid placing nests on dry, upland shorelines.* Instead, they usually locate nests on islands, marshes**, or bogs hard for terrestrial predators to reach.*** So one key to loons’ ability to coexist with humans is merely loons’ preference to nest where humans cannot build.

Hodstradt Lake in the Wisconsin Study Area illustrates the complementary use of shorelines by loons and humans. Hodstradt is a 119-acre lake that has beautiful clear water with a slightly greenish hue. The lake is full of fish but completely encircled by lake homes. There is no island, marsh or bog in Hodstradt — only a peninsula in the southeastern corner (see screen grab below from Google Earth). Almost all nesting attempts by loons on Hodstradt have been on the end of that peninsula. High water caused by heavy rainfall in the past decade submerged the narrow spit connecting the end of the peninsula to the mainland, making it a small island. Whether an island or a peninsula, though, the land is low lying and impossible to build on. Hence it provides permanent nesting habitat for loons that is off limits to humans.

A similar situation exists for many loon pairs in the Minnesota Study Area. The seven pairs that nested this year on massive Cross Lake provide a good example. Three of these pairs nested on small uninhabitable islands; three nested among dense cattail patches in marshy coves; and one used an artificial nesting platform. (Five of these pairs hatched chicks.) Thus, the “Jack Sprat” nature of loon and human shoreline use can be seen in both Wisconsin and Minnesota. With rare exceptions, sites safe for loon nests are sites where humans cannot or will not build.

So adult loons are able to put chicks in the water despite extensive shoreline development. This would seem to be cause for celebration. In a cruel twist, though, shorelines altered to support suburban-style homes, lawns, and driveways have increased runoff. Although we are still working out the details, it appears that higher runoff has, in turn, produced a decline in water clarity and decreased chick mass, probably because adults cannot see fish well enough to provision their chicks adequately. In short, shoreline development negatively impacts loons during the second critical breeding phase: chick-rearing. Indeed, the sharp increase in mortality of chicks and young adults in the past two decades has become our number one concern with respect to the Upper Midwest loon population.

If there is a silver lining, it is this. Loons are resilient. They have been able to find nesting sites and sustain a high hatching rate despite everything humans have thrown at them. Perhaps we can help loons reverse the decline in chick survival, if we can learn precisely what is driving the drop in water clarity. This will be a massive challenge. But I have to believe that loons can come back from this setback. It keeps me going.

* We learned 16 years ago through marking of loons and systematic tracking of nest placement that male loons choose the nest site. For those not interested in looking at the science, we know this from two facts. First, loon pairs learn where to nest by trial and error. That is, they tend to reuse a site where they hatched chicks the previous year but move to a new nest location after egg predation. This logical nesting strategy is called the “win-stay, lose-switch” rule. Second, loon pairs in which the female pair member returns from the previous year but the male pair member does not usually do not reuse a successful site from the past year. In contrast, pairs consisting of the male from the previous year and a new female tend to reuse successful sites. In short, pairs with new male members do not use the win-stay, lose switch rule. They act as if they have forgotten where the best nesting site is.

** The featured photo is of Clune, Linda Grenzer’s favorite male loon, who bred for many years in her lake in Wisconsin. He is incubating eggs in a marshy corner of the lake that, predictably, is devoid of homes.

*** Of course, humans often accomodate loons’ nesting preferences by placing artificial nesting platforms along lake shores. Platforms provide very attractive nest sites for loons.

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Loon pairs experience many setbacks during the course of a breeding season. Black flies drive them off of nests in May. Eagles take chicks. Intruders force them to expend energy in territory defense or even evict them. Rainfall clouds the water, making it difficult to find food for chicks. It is largely a pair’s ability to bounce back from such adversity that determines how successful they are at fledging young.

The loons at Big Trout-Far West, part of the Whitefish Chain, faced more than their share of challenges this summer. All seemed good in May, as the pair shared incubation duties on their two eggs (see photos above by Karl Olufs*). When they hatched two healthy chicks on June 9th, the veteran male and female breeders seemed poised for a fruitful year. But their luck turned. On June 12 a freak storm dropped golf-ball-sized hail to across much of the Minnesota Study Area. One three-day-old chick took refuge under a camp’s pier, while the second remained out in the chop. Following the storm, the exposed chick was found dead on shore, and only its sibling remained. In a poignant moment, one of the parents left the water and sat on shore beside the deceased chick, before returning to tend its surviving sibling.

Three-and-a-half uneventful weeks passed, and the surviving chick grew. On July 6th, though, the male, who had been healthy the day before, died suddenly and violently, a likely victim of a boat or jetski collision. For a few days, the female cared for the chick alone. But a new unmarked male soon noticed the lack of a male defending the territory and joined the female. Unwilling to rear a chick not his own, the new male grabbed the chick, shook it violently — as a horrified lake resident looked on — and killed it. In a month’s time, the original family of four had been reduced to one.

When Richard Rammer and I visited the Far West pair on July 26th, they were resting quietly in their marshy cove, as if in recovery. The female cooed repeatedly to her new mate, trying to coax him to search for a nest site. He sat quietly a few meters away, unmoved. There was something touching in the female’s stubborn unwillingness to accept defeat. Battered as she was by misfortune, she was looking forward — seemingly determined to lay the groundwork for a successful 2025 breeding season.

As horrid a year as the Far West pair had, they are only one pair. Elsewhere on the Whitefish Chain, the news was better. The pair at Island-Channel, which adopted a doomed chick in June, still had both their biological chick and the fostered one. Despite the apparent vigor of both chicks, I had nagging concerns. Was the biological chick getting more food? Were the chicks still bickering? The scale told the story: both chicks weighed in at a strapping 2.42 kilograms on the night of July 20th, when we caught the entire family.** Their future looks bright. Good news emerged too from a second pair on Island Lake, which abuts the Island-Channel territory. There an unmarked pair have raised a chick to five weeks of age and are likely to fledge it.

Even on Big Trout, where boat traffic is constant and rapid, a glimmer of hope emerged. Big Trout-Central, a few miles east of the ill-fated Far West pair, has raised a chick that recently turned five weeks of age. If it can dodge boats, jetskiers, and eagles for the rest of the summer, it will be the first fledgling from that territory since 2020.

Cross and Rush Lakes each contain three breeding pairs with chicks. The total of eight chicks between the two lakes is mediocre, considering the dozen territories they support. Still, among the chicks is a singleton produced by an all-new Rush-Boyd pair that bounced back from a chickless year in 2023.

Daggett Lake had an off year. Neither the Northeast nor Southwest pair hatched eggs, while the Channel pair hatched two healthy young from an island but lost them in the first two weeks. On the other hand, the Little Pine-Dream Island pair is enjoying their fourth consecutive productive season, raising two enormous independent chicks just north of the channel from Daggett. The news is also good from Pig Lake, where a new pair is raising two huge chicks after an off-year in 2023. The pair on Bertha, chickless for the past three years or more, also has two gigantic eight-week-old chicks. Sadly, the Upper Whitefish-Steamboat pair lost two small chicks in the same freak storm that cost one of the Far West chicks its life. But two of four pairs on Lower Hay (Northeast and Southeast) have chicks that are fit and strong. By raising a chick this year, the Northeast pair broke a slump of at least three years without young.

Loons in the Outing/Fifty Lakes section of the Minnesota Study Area, like those on Cross and Rush lakes, were only moderately productive. Roosevelt and North Roosevelt, between them, yielded only two fledged chicks this year. West Fox and East Fox pairs looked good early in the year. But the disappearance of the East Fox-South male resulted in loss of two chicks, in spite of the heroic efforts of the female to rear them alone. Furthermore, late loss of a large chick on West Fox-Stone Man whittled down the productivity to three chicks between the two lakes. Eagle Lake, similarly, yielded only one fledged chick. A mere two chicks emerged from Eagle, Kego, Butterfield, and Mitchell lakes combined this year, in contrast to the six produced in 2023.

There was a pleasant smattering of chicks on small lakes in the Crosslake region. Goodrich-West and -Southeast pairs both raised chicks successfully, and two new breeders on O’Brien beat all odds by hatching a late chick there. Kimble-East was a washout, but Kimble-West, Clear-North and -South, Star, Big Pine, and Grass lakes together raised eight chicks.

Lakes in the southwestern portion of the study area had an especially impressive breeding year. Ossie pairs raised five chicks in all. Pairs on Upper Hay, Nelson, Sibley-North and -South, Fawn, West Twin and the Cullens produced chicks at above-average rates, as did those on Roy-North and Roy-South and Nisswa. Pairs in the Upper Gull area did particularly well, including Mayo Creek, Boathouse, Bass Lake and Margaret-North pairs.

In short, the cruel summer at Big Trout-Far West did not typify the breeding season overall for the Whitefish Chain or the Minnesota Study Area as a whole. Stepping back to view the season from space, it was a decent breeding year. Low and short-lived populations of black flies early in the year helped get the season off to a solid start. Alas, the abundant rainfall we have had this spring and summer means that we cannot count on the continued paucity of these pests in 2025. For the moment, though, let’s shrug off the disappointment at Big Trout-Far West and enjoy the rather productive breeding year for loons in central Minnesota!

* Thanks to Karl Olufs and his sister, Janet, who paddled her kayak out to meet us on July 26th to relate the saga of the Big Trout-Far West pair.

** The male of the Island-Channel pair is an interesting loon in his own right. Hatched in 2016, he is among the handful of loon chicks marked with silver numbered bands by Kevin Kenow of USGS. Upon his capture, we read the number etched into his band and discovered that he was raised on the Big Island territory on Upper Whitefish in 2016. Thus, he is a whippersnapper at 8 years of age. He is the first known-age loon to settle in the Minnesota Study Area.

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Loon’s inhabit an unpredictable natural world. Black flies swarm them early in the year, often making incubation impossible. Coyotes, fishers, eagles, and raccoons ambush them on nests and take eggs — and sometimes loons themselves. Eagles swoop by unexpectedly to grab a chick that strays.

It seems unfair to add humans to the mix. Yet humans pose by far the greatest danger to loon survival and reproductive success. High summer brings a surge of anthropogenic challenges: some mild, some severe. Boaters unwittingly push loon families out of their favored foraging locations. Jetskis elicit yodels and tremolos from loon parents fearful for their chicks. Inattentive — and occasionally malicious — boaters deal a deadly wing or neck blow to an adult loon or chick. Anglers hook loons and cut fishing lines. Of course, we now understand that indirect impacts on northern lakes — especially loss of water clarity — pose the greatest threat of all to loons.

Some human impacts on loons are difficult to fathom. The July 4th holiday celebrations — always feared by loon enthusiasts and researchers — affected loon families on Roy Lake, Minnesota, in a manner that we had not seen before. We knew that surges in boating, fishing, and general hijinks would force loons to spend much of the holiday ducking, dodging, and diving. But we did not anticipate that fireworks and boats might scramble up loon families.

The precise events are difficult to discern. Here — according to Sheila Johnston and folks on Roy who watch the two breeding pairs closely — is what we know. On July 2nd, the Roy-South loon pair had two huge chicks. That night, many boats criss-crossed the waters of Roy-South to watch the Grandview Lodge — a large resort on Roy — shoot off a massive fireworks display. The following day one of the two chicks from Roy-South was missing. On the same day, the Roy-North breeding pair, which had two medium-sized chicks on July 2nd, suddenly had three: their own two and a much larger one. The only plausible explanation for these events is that one of the two Roy-South chicks became disoriented by the boisterous flotilla during the previous night, blundered into the North pair, and unwittingly abandoned its own family to join a new one. (Sheila Johnston took a photo that shows the “monster chick” from the south end next to one of the smaller chicks from Roy-North.)

There is good news. The adoptee has been fully accepted by the Roy-North pair and its two smaller step-siblings. All three young are being fed by the parents. So what could have been a human-induced disaster became a sweet story of a loon family willing to accept an unrelated chick that had lost its way. Loon lovers can, in this case, breathe a sigh of relief.

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Sibling rivalry is a fascinating but intellectually thorny behavior pattern. Why would a young animal hurt its own flesh and blood? To put it scientifically, why would an animal harm its full sibling when that sibling shares half of its genes and when the ultimate goal of animal behavior is to increase the abundance of one’s genes in the next generation?

But normal rules do not apply when food is limited early in life. If the food supply is inadequate to keep all members of a sibling group alive, then the only sound evolutionary strategy for each sibling is to battle mercilessly and become a survivor.

Such is often the case in loon families, especially those living on small lakes. Even with only two chicks to care for, loon parents are all out to keep them alive. This scenario creates the haves — chicks that hatch two days before their siblings and use their size advantage to pummel them and gain a greater share of the limited food that parents can find — and have-nots.

What of the have-nots? To avoid beatings from an aggressive older sib, a typical younger sib lags behind its family and, as a result, receives fewer feedings. It becomes weaker over time, is less able to defend itself, suffers more beatings, and begins to avoid its family altogether. Unable to escape this downward spiral, most beta chicks perish from starvation. Some undoubtedly fall prey to eagles.

But not all starving beta chicks die quietly on their home lakes. Sometimes a chick in such dire straits abandons its home and kin and strikes out over land in hopes of finding a new family of loons that will feed and protect it. If it sounds preposterous that a weakened, helpless loon chick would trek through the woods in hopes of being welcomed by a foreign loon family, it is. Only the prospect of certain death at home could induce a chick to make such a reckless, fanciful journey. And yet such “chick odysseys” happen commonly at this time every year.*

We are four weeks into the chick-rearing period in both Minnesota and Wisconsin study areas. So this is the time when a small cohort of starving second-hatched chicks from small lakes across the Upper Midwest are abandoning their abusive older siblings to seek a better life elsewhere.

A two-week-old chick in north-central Minnesota took this desperate approach. A good samaritan stumbled upon the brown puffball on a roadside and carried it a rehabber. But the rehabber had no future to offer the chick. Only loons can raise loons. In fact, only adult loons who currently have chicks of their own are (sometimes) willing to accept these waifs.

It is a chancy business to match a parentless chick with a foster family already rearing a chick. The chief danger is lack of acceptance by the biological chick. If the natural chick attacks the chick you are trying to add to the family, you are back to square one. Folks who attempt fostering of this kind report a success rate of about 35%.

The loon pair of Island Lake on the Whitefish Chain had a single two-week-old chick — very close to the size of the chick found on the roadside. As shown in the video below, the homeless chick quickly joined and bonded with the Island family. After an initial tussle with its new sibling ended in a draw, the biological chick seemed to resign itself to the new addition. Both chicks remained peacefully together this afternoon, three days after the introduction.**

Introduction of rehabbed chick at Island Lake, Whitefish Chain, Minnesota.

We have no idea what the future holds for the adopted chick. Starvation, predation, a boat strike, or fishing entanglement might end its life before it reaches fledging age. Yet a chick that was a longshot to survive two days ago is suddenly ensconced with a protective new family. And this former have-not now stands a decent chance of reaching adulthood. It is hard not to feel good about that.

* Though these journeys are the most desperate of long-shots, they do not always fail. In fact, we had one case where a chick that fled across land reached a new lake, gained two new siblings, and lived happily ever after.

** The top photo shows the Island Lake pair and their two chicks as of June 28th at 1pm. Evrett Fiddian-Green, who took this photo, reports that both chicks are being fed by the parents. Most important, the chicks are not fighting.

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I was skeptical when I first got the news from Melonie and Gin on East Fox Lake in Minnesota. “Larry”, they said, “has been missing for weeks.” Melonie and Gin have a bird’s eye view of the bay where the East Fox-South pair nests.* They know the bands of both adults, whom they call Larry and Lola. Very little that occurs on the territory escapes their notice. “We watch our pair like others watch TV”, Gin told me recently.

I should not have doubted them. And yet I am a scientist and have studied loons for 32 years. I am used to hearing reports of loon behavior that range from strictly factual and incisive……to 50% truth and 50% dramatization to….well, pure fantasy. So I followed up. “Missing?” I said dubiously. “He has not been positively identified since June 5th,” Melonie replied, “and we have seen only Lola incubating the eggs since at least a week before that.” She added that stretches of many hours had passed in early June during which Lola was off the eggs. Larry, who should have been incubating at such times, was not present. My team’s visits too confirmed Larry’s sudden absence.

I was convinced. Larry had vanished sometime in late May or early June.

Members of breeding pairs occasionally disappear. That alone is not news. Lead poisoning from fishing tackle, boat strikes, disease, and territorial battles sometimes claim one pair member in the middle of a breeding attempt. Faced with the loss of a mate, most adult loons — male or female — make a gut-wrenching but rational decision. They suspend the breeding effort, wait to find a new mate, and attempt to breed again later in the season, if time permits.

But Lola did not give up. In fact, hers is the first case we have documented of a loon of either sex losing its mate during incubation and incubating the eggs alone.** When both eggs hatched successfully on June 7th, Lola became a single mom.

Parenthood is a stressful business among loons. Lola had already challenged herself by choosing to warm the eggs on her own. Her obligation to protect and feed the two helpless hatchlings that emerged from those eggs raised the bar considerably.

I am not knocking Lola herself or females generally by describing the pickle she is in. Lola is a seasoned breeder who has proved she knows how to raise young. But female loons are 20% smaller than males. Indeed, at 3580 grams, Lola is slightly smaller than the average female. The real handicap that single loon moms face is the lack of a crucial vocal tool. You see, male parents save their families considerable time and energy by yodelling to discourage intruders from landing near the chicks. Lacking this vocalization, Lola must respond to territorial intruders either by hunkering down and hoping to remain unseen or confronting the intruders while stashing the chicks near shore.

The two chicks at East Fox-South are now two weeks old. As Melonie’s photo shows, they look good and are being fed steadily by their devoted mom. They are also of similar size, which suggests that Lola has been able to satisfy the needs of both chicks and prevent the corrosive sibling rivalry that often occurs in two-chick broods. But the family still must survive countless territorial intrusions and eagle flyovers before the chicks reach independence. Keep a good thought for them!

* Thanks to Melonie Elvebak for this nice photo of Lola alertly watching out for her brood.

** Back in 2005, a male on Alva Lake in Wisconsin faced a similar choice to Lola’s. An eagle killed his mate on the nest. Like Lola, he incubated the eggs alone for several days. But ultimately he could not balance his breeding attempt with his need to keep himself alive and healthy. So he gave up.

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It was just a bag in the water. But it was a large white plastic bag, one flap of which protruded above the surface of Little Pine Lake in our Minnesota Study Area. As Evrett, Isaac, and I paddled across the southern end of Little Pine to begin our observations of the Dream Island loon pair, the bag caught our eye and sullied the otherwise idyllic Northwoods scene. Looking to leave the lake a bit cleaner than when we had arrived, we fished the bag out of the water.

The writing on the bag told the story.

I have a confession to make. I come from a family of non-gardeners. When we see a beautiful tree or flower, we savor it. But the notion that some act of ours might alter the health or appearance of a plant is altogether foreign. A product of suburbs of large cities, I have grown accustomed to gazing at the verdant, manicured lawns and gardens of neighbors — then turning to look ruefully at my own. Yet jealousy of my neighbors’ lawns is not enough to induce me to follow their lead.

Of course, the suburbs are one thing. Lakeshores are quite another. The bag that Evrett fished out of Little Pine suggested that a resident on Little Pine was placing fertilizer on their lawn. While the decision of how to treat one’s lakeshore is up to each individual, it has consequences for all of us. Inevitably some of the high-nitrogen and -phosphorous fertilizer that produces a lush green lawn by the lake washes into the lake when it rains. Lake phytoplankton — free-floating, microscopic algae that inhabit all lakes — are starved for nitrogen and phosphorous just like grasses and trees on land. So adding fertilizer to lakes causes higher-than-normal growth of phytoplankton, which reduces water clarity and can have a variety of more serious impacts on lake-dwelling animals and plants.

It is too early to tell whether lawn fertilizer is at the root of the water clarity loss in the Upper Midwest during the past quarter century. We do know that heavy rainfall causes low water clarity. And we know that low water clarity hinders loon parents’ feeding efforts and produces emaciated chicks. But while we investigate the specific cause of water clarity decline, wouldn’t it be prudent for lake residents to stop using fertilizer on lakeside lawns, in case loon chicks are unintended victims?

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By the way, Wisconsin Public Radio did a short segment on our study and on the decline in water clarity we have reported recently. If you wish to hear how I sound after a day of field work and a bit too much coffee, you can find it at this link.

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I went on a tour of Upper Gull Lake territories in Minnesota on May 15th. Most loon pairs there were incubating eggs.* The same was true last week when Hayden and I checked out many territories in Wisconsin. And Kaidan and I found more of the same after I returned to Minnesota a few days ago. Over a third of our breeding pairs in both states are recovering from nest failure — mostly owing to black flies. But the remainder have weathered that storm and are close to or even beyond the halfway-point of incubation.

As Sheila Johnston put it eight days ago when she and her friend Darcy led me around the Upper Gull breeding territories, we are in our annual “period of hope”. The burst of excitement and territorial intrusions of April and early May have passed. Breeders have re-paired with their old mates or replacements, established a firm grasp on their territories, and are standing vigil over their eggs.

If there is little for loons themselves to do during incubation, there is even less to do for humans who wish them well. Unless you choose to chase away eagles — Taryn Schultz on Upper Whitefish told me yesterday that a “bear horn” is her weapon of choice for this task — we can only watch with crossed fingers.

And so we wait. But our waiting is not laced with dread. It is not an “I’m afraid to look” sort of waiting. Ours is an expectant waiting — one warmed by the knowledge that we are a few weeks away from the emergence of comically small, chocolate brown puffballs that behave like awkward, bumbling adult loons but otherwise resemble them only faintly. The appearance of these puffballs brings the hopeful tedium of incubation to a most satisfying close.

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* The striking photo of the Upper Gull – Causeway nest in the Minnesota Study Area is by Sheila Farrell Johnston, who led me on the tour of the Upper Gull – Causeway on May 15th. Thanks, Sheila!

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Last year I reported precocious territorial behavior by one two-year-old in Wisconsin and another two-year-old in Minnesota. These sightings were extraordinary. Before 2023, we had no record of an adult loon younger than four years of age holding or attempting to hold a territory. Naturally we were excited to see whether those youngsters would return at age three and continue to show assertive territorial behavior well ahead of schedule.

We were not disappointed.* “Junior”, as I reported recently, is firmly ensconced on the Oneida-West territory in our Wisconsin Study Area. Meanwhile, the now three-year-old who seemed determined to settle on Pig Lake on the Whitefish Chain last July appears to have claimed the Ossawinnamakee-Boozer’s Bay territory…..and is nesting! This young Minnesota male** was hatched in 2021 by the Ossie-Muskie Bay pair. So he has settled only a few miles from the territory on which he was raised three years ago.

It is cool to see two loons in different states set the record for youngest territorial breeder simultaneously. This finding suggests that all adult-plumaged loons, even very young ones, are capable of breeding. The result also implies that many young adults would settle and breed if the habitat were not already occupied by older loons.

Could it be just a wild coincidence that two such unlikely settlements transpired at the same time? Yes, it could be. As someone whose job it is to look for patterns, though, I think I see the beginning of one here. We know from past work in Wisconsin that four, five, and six year-old adults are bigger, stronger, and more competitive for breeding territories than two and three year-olds. We know also that the pool of four to six-year olds looking for territories has become depleted by poor breeding success over the past decade. In other words, fewer chicks fledged has led to fewer young competitors scoping out territories to claim. The sudden settlement of two very young adults in Wisconsin and Minnesota suggests that territorial competition has softened to the point that two- and three-year-olds can now compete for and claim territories.

So the excitement of watching territory settlement by very young adults is tempered by the nagging concern that these events are further evidence of a downturn in the breeding population. But maybe I am overthinking it. For now, let’s savor the spectacle!***

* These cool findings are not mine. Hayden and Claudia, our scouts in Wisconsin and Minnesota, found and ID’d each of these adults on territory. Kudos to these two outstanding field workers, who have braved cold, damp conditions to ID returning breeders in both states!

** I initially called this bird a female on the basis of size. It seems I was wrong. Its settlement so near its natal territory makes the loon almost certain to be a male.

*** The featured photo above is by Claudia Kodsuntie, who scouted our study lakes in Minnesota. It pictures the hind 3/4 of the 3-year-old adult on Ossie-Boozer’s Bay. The photo is not beautiful. I like it, though. It shows the kind of quick underwater view of colored leg bands that one often gets during the early census period. So it gives you a good idea of the challenges that Claudia and Hayden have oversome to make this blog post possible.

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I left you hanging last July. A young adult male in Wisconsin seemed on the brink of achieving two spectacular firsts for our long term study. He was attempting to settle at the age of two, two years younger than any male or female loon had ever settled. And he was making a play to claim his natal lake as a breeding site, which we have never observed. In the end, his effort fell short. “Gs/C,Y/S” — whom Linda calls “Junior” because he is the son of Clune, the long-time male on her lake — could not sustain his hold on Muskellunge Lake. For a time, he fell off our radar.*

But the Loon Project scout for Wisconsin this year, Hayden**, found Junior — now all of three years old — on Oneida-West earlier this week. (Oneida Lake is just over 7 miles from Muskellunge Lake, Junior’s natal lake.) Junior has not been idle. He has paired with one of our best-known females, “Silver/Blue,Orange-dot over Orange-dot”. Let’s call her “Dot”.

Dot is the second oldest adult loon in the Wisconsin Study Area and an accomplished breeder. She was banded in 1997 on the Oneida-East territory, where she reared 22 chicks to adulthood between 1997 and 2013 with two different males. Dot was evicted from Oneida-East in 2013, but that did not stop her. She moved around a bend in the lake to the Oneida-West territory. Between 2014 and 2020, she raised 3 more chicks to fledging with two different males on Oneida-West. In 2021 she again lost her breeding position to a younger female. I thought we had seen the last of Dot. But female loons are nothing if not resilient, and Dot was not ready to quit.

We are not sure what to expect from this unlikely pairing. Three-year-old Junior would shatter all records by merely building a nest and beginning to incubate eggs. And 31-year-old Dot is astounding us simply by remaining in the game. We have never seen such an inexperienced male pair with such an accomplished female. Whatever happens from this lopsided pairing will be a surprise. I guess this is why I continue to study loons.

*The featured photo is by Linda Grenzer. It shows Junior on her lake back in June of last year.

**Hayden is doing his own impression of Junior. Although he knows Oneida County well, Hayden is new to loon field work and ID’ing loons from leg bands. Not a problem! Hayden is sweeping efficiently across the study area, identifying territorial adults like a seasoned pro. If you see him out on your lake in his canoe, give him a pat on the back for his incredible efforts this spring!