ABOUT OUR LOONS AND THEIR PONTOON

All photos by Pete Wuebker

Nothing evokes the onset of spring and summer in the Northwoods more than the haunting call of the loon.  Mournful loon phrasing and trilling before dawn and at twilight can be as soothing as the rhythmic slap of wavelets against a scow.  Loon wails can make a heart begin to ache, and their hoots and yodels can signal recognition that all is well.

Loons are the original “snowbirds,” spending their winters fishing in in the Gulf of Mexico, and returning to the north with the advent of warmer temperatures.  Most of us will recognize the various vocalizations of the loon.  But I found these descriptions and explanations fascinating:

Loon Tremolo

The tremolo has been described as “insane laughter”; it is 8 to 10 notes voiced rapidly which vary in frequency and intensity. This alarm call usually indicates agitation or fear, often caused by disturbance from people, a predator or even another loon. This is also the only call that loons make in flight.

Loon Wail

The wail is most frequently given in the evening or at night, and can be heard for many miles. This haunting call is not an alarm call but is used to keep in contact with other loons on the same lake and surrounding lakes.

Loon Yodel

The yodel is only made by male loons. This call is used to advertise and defend their territory, especially during incubation and early chick-rearing. If you are watching loons and they make this call or a tremolo, it usually means that you are too close and are disturbing the loons. If that happens, you should leave their territory and give them their space.

Loons are swift divers, and thus great at fishing.  They’ll abruptly disappear beneath the surface and emerge unexpectedly hundreds of feet away.  Loons will return to the area where they were hatched, and pairs are very territorial.  Chicks incubate for 28 days, and then peck their way out of their eggs, ready to swim.  Frequently they hitch a ride on their parents’ backs, though, in one of the most appealing traits ever.

We’re lucky at the cabin to be blessed with a nesting pair of loons every year.  Normally, loons will nest along island shoreline, building their hatchery out of mud, stems, reeds and dried grasses.  The problem with this habit is that the eggs are vulnerable to four-legged predators, like raccoons and fox.  Years ago, Grandpa and Grandma (Pete’s mom and dad) decided they would encourage a pair to set up safer housekeeping, and Grandpa built the first “loon pontoon.”

The loon pontoon is a simple floating structure Grandpa designed.  His first prototype was made of wood.  In this photo, he and his brother-in-law, Pete’s Uncle Doc, are launching the pontoon off the dock in the lagoon in front of the cabin.  On the platform you can see the grasses and mud the parents-to-be will rearrange and add to, constructing a hatchery to their liking.  One question:  how come Doc is nattily dressed and staying dry on this occasion, and it looks like Grandpa has already been up to his neck in the drink? 

The loon pontoon doesn’t ensure a totally safe haven.  Even though Grandpa anchors it in the reeds, depending on the year, the sitting parent (both take turns incubating the eggs) is exposed to predators from the sky (eagles and ospreys) or in the water (muskrats, otters, and rogue single loons).  It must be nerve-wracking.  The loon often scans the sky and its surroundings, and its mate will often reappear from fishing to do guard duty and take a turn on the nest, too.

Watching the shift change is fascinating, too.  Loons are so graceful in the water, but they approach the nest from one side and clamber up onto the pontoon on one side in a clumsy fashion, finally settling in.  The dimensions of the pontoon have to be sufficient so that it doesn’t tip from the weight of the adult’s movements.

After several years, Grandpa redesigned the loon pontoon.  The wooden structure became waterlogged, so he switched to lighter weight materials, including pvc pipe underneath to make the frame.  The middle is heavyweight woven galvanized wire, so it holds the heavy nest and doesn’t rust.

You can get a good look at the nesting loon from this year in this photo that Pete took last weekend while we were up at the cabin.  We were hoping that this would be the weekend that the egg would hatch, but no such luck.  Babies come when they’re ready and not before!

This year the nest is more exposed than it has been in past years.  This means it can be more easily seen from the sky and from the water.  Pete was standing at the window this weekend when all of a sudden a bald eagle swooped into the lagoon.  The eagle’s aerial theatrics were enough to frighten the parent loon off the nesting platform and into the water.  Pete was screaming and hollering for the half a minute the spectacle occurred.  The eagle didn’t take the egg, however.  Tragedy averted this time.

I must say Pete isn’t as quick on the draw as his mother is.  We’ve all seen Grandma take off lickety split toward the water’s edge, flapping her arms and screaming at an eagle to get out of the bay.  She does this to strange fishermen who inadvertently get too close to the pontoon in other years when it has been better hidden by plant surround.  For such a tiny person, she can threaten serious harm to all kinds of interlopers! 

This year for our anniversary, our friends Judy and John got us a signed copy of Loon Summer, by Sandy Gilllum.  Sandy and her husband have a loon pontoon in Wisconsin.  Her narrative contains history and behavior, as well as thrilling photographs of hatchlings.  Sandy has done an amazing amount of study and has captured the world through the loon’s eyes in this book.

Some years our pair has had two eggs, which happens quite frequently.  This year, there is just one.  A couple of years ago, it appears we had a pair mis-match.  The male just couldn’t seem to “get” what he was supposed to be doing, and the nest was abandoned in mid-season.  Three loons frequented the area that year.  We wondered if they were adolescents who weren’t quite ready to settle down.  Reading Sandy’s book has shed a little light on some of the more mysterious behavior, as well as the typical parenting loons do.

My brother, John, called to say there is a pair of loons on our lake in Michigan this year, a remarkable occurrence.  Usually, they don’t stay that far south.  He is keeping his fingers crossed.  Our land is an island-like peninsula, so maybe they will nest!  We’re farther north in Minnesota.  On Woman Lake there are many pairs of loons, and a full range of predators and food to support the population in a balanced ecosystem.  It’s something we don’t take for granted.

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