Growing Up in Two Worlds

It is the July 4th weekend, and families are gathering, as they can, to spend the holiday together.

Though it happens with no advance planning and much less fanfare, loons too occur in tight family groups at this time. Their concerns, however, are rather mundane. Loons with chicks — especially small ones — just seek to keep them alive over the July 4th holiday. If loon parents can steer their young clear of inebriated speedboaters, dodge mischievous jetskiers, and elude countless fishing lines, lures, and deadly lead sinkers that are either in use or have been carelessly left in lakes, then they have a fighting chance to fledge them. The collective deep breath heaved by loon enthusiasts across the northern tier of North America just before the July 4th weekend produces an audible susurration picked up by remote sensing devices in the region.

Of course, some loon parents face greater obstacles than others in rearing and protecting their young. Pairs that must defend two chicks face greater stress than those defending only a singleton. No doubt that explains why males in pairs raising two young yodel three times as often as those with one. Now, imagine if you had not only two chicks to care for, but three, like the Bass Lake pair did in 2019.

As you might recall, a breeding loon pair in northwestern Montana accepted an even greater challenge. Bob LeBlanc has been dutifully observing, recording on video, and reporting on loon parents there that are rearing three young not even of their own species. And Bob has generously allowed me to share the story of this non-traditional avian family.

The three Montana goslings swim with a parent in their first week of life. Photo by Bob LeBlanc.

To my utter astonishment, the three loon-reared goslings are thriving. Bob’s reports show, moreover, that the goslings live a dual existence. Having evolved as nibblers on vegetable matter in fields and along shorelines, the three youngsters have had to adjust to foster parents that wish them to be on the water at all times. That adjustment seems minor for three malleable young waterfowl. Their wholly aquatic parents face a steeper climb, as they must watch over their charges whether on land or sea.

Three goslings rest together on the ground at the lower right, while two much-larger goslings from another family feed to the left. A watchful loon parent (the female in this case) remains nearby in the water. Video by Bob LeBlanc.

Bob’s video shows three things. First, the loon-reared goslings behave more or less like goose-reared goslings at most times. That is, they feed on shore extensively and rest there as well. Second, the nervous foster parents do not abandon them during their lengthy visits to shore but instead stand guard from a few meters away in the water. Third, although the goslings are comfortable on shore and fraternize with goose-reared goslings at such times (note the much older goslings in the first video), they know who their parents are and flee to them reflexively when danger approaches (as in the video below).

Three goslings flee quickly from shore, where they were resting, to the safety of their loon parent, as a threat looms. Video by Bob LeBlanc.

One more fact is not obvious from the video, but has been captured by Bob in still photos, such as the one below. Like the famous mallard duckling from two summers ago, the goslings are ravenous and opportunistic in acquiring food. Ducklings and goslings are not fed by their biological parents. So we might wonder what a newly-hatched gosling or duckling thinks when its loon foster parent leans down to it for the first time and offers a small minnow or crayfish. What do goslings and ducklings do? They grab the food, making it plain to the loon parents that they find this practice quite acceptable, despite their lack of genetic predisposition for it.

A gosling lunges for a fish presented to it by its loon parent, while its sibling looks on with jealousy. Photo by Bob LeBlanc.

And, oh yeah, the goslings have also learned to do something else that goslings do not normally do: they dive!

Lengthy dive by one of three loon-reared goslings. Video by Bob LeBlanc.