An Injury, a Takeover, and Some Desperate Parenting

Three days ago, Allison and I had only one car, so we covered a double circuit of lakes. We loaded two solo canoes precariously on top of our ’07 Toyota Corolla — “That seems safe”, I said, tugging on one of the straps we had used to lash the boats to the roof rack and smiling reassuringly at my dubious daughter — and headed to a northern tier of lakes. I dropped her and her canoe at Brandy, and scurried across Highway 51 to Arrowhead. An hour and half later I covered Kawaguesaga-North, while she observed at Bullhead, and so forth throughout the day. It was tiring, and Allison inevitably had to wait ten minutes or so for me to drive back from my lake to hers, but we visited four sets of lakes this way. Covering many lakes with limited personnel is central to the ethos of the Loon Project, and I was delighted to walk the walk on Sunday.

While our highly fuel-efficient observations on our last day in the field were very cool, the portrait of reproductive success that emerged from the lakes I visited was decidedly ambiguous. The Hodstradt pair has two thriving, five-week-old chicks. During my visit, the ten-year-old female (hatched on Butternut Lake in Forest County) was struggling to provide enough food for her large family. The alpha chick begged her mercilessly and received 14 feedings. In contrast, the beta chick, which only got two food items, was on the receiving end of three harsh pecks from his larger sibling. Still, Hodstradt has a history of producing two-chick broods, so they appear to stand a good chance of fledging both young. 

In contrast to the thriving family at Hodstradt, the Arrowhead breeding pair has been impacted heavily by a wing injury to the male. Even as I began to pull the canoe off of the Loonmobile, I saw a large loon preening awkwardly forty meters off the Arrowhead boat landing. “Uh-oh”, I thought. The telltale drooping of his right wing revealed the male’s identity long before I observed his plastic leg bands. He was alert and responsive to his environment, but he looked worse than ten days before, when we had captured him at night and inspected his injured right wing. I sighed and shook my head; we had hoped he would recover and rejoin his mate and chicks. As I took note of his struggle to preen without stretching his damaged wing, his sodden plumage (which occurs when loons fail to cover themselves with protective oil from a special gland near their tail), and his willingness to permit a fisherman to drift to within ten meters, a grim realization hit me. This male is going downhill rapidly and is not going to recover. (Marge Gibson, a veterinarian with REGI, has inspected a series of photos taken by Linda, and is confident that the right wing is broken — probably at the humerus — an injury she has seen often after severe blunt-force trauma such as a strike by a motorboat or jetski.) Despite the male’s injury, I wondered why he was confining himself to the small, protected cove off of the boat ramp, instead of remaining in the main body of the lake.

I quickly learned why the wounded male was hiding. A pair of loons rested confidently on the southwestern end of the main bay. Unlike the injured bird, these two sat up high on the lake surface. A short time later, they foraged in plain view in the middle of the lake. In other words, they acted like they owned the place. Clearly the male had taken refuge in a protected cove in order to hide from these two new adults that, in the absence of territory defense, had laid claim to the lake. Indeed, the new pair swam east to the mouth of the male’s cove as I observed them, as if hunting an intruder they wished to drive from the lake. I was relieved that neither pair member gave any sign that they detected the injured male in the cove. Somehow — either by diving often, hiding under a dock, or perhaps pulling himself up onto the shore — he eluded them and spared himself their attacks.

The wounded male was not the only loon systematically avoiding the new breeding pair at Arrowhead. As I patrolled the shoreline of the lake, I found his mate foraging madly for one of their two chicks in the northeastern section. Though her territory has slipped away because of her mate’s and her own inability to defend it, the female has been unwilling to desert her seven-week-old chicks. In order to avoid the watchful eyes of the new pair, she and the banded chick I found her with always remained within ten meters of shore and foraged among a stretch of long docks that jut out from the northeastern shoreline. As my video above shows, the chick begged his mother relentlessly for food, while she captured what few small fishes and insect larvae she could find along this sandy stretch. This brief set of observations provided a window onto the female’s plight. In order to fledge her two chicks, she must provision them surreptitiously for at least another month, wait for them to learn to fly, and then hope that they can move to nearby undefended lakes (which chicks naturally do at this age), where they can complete the growth process. The series of practice runs, aborted takeoffs, and awkward landings necessary for a chick to become adept at flight are sure to draw the attention of and aggression from the new breeding pair. If, by some quirk or miracle, the female manages to keep the chicks safe and healthy until they can fly, she will be the first adult we have ever seen to lose her mate when the chicks were younger than five weeks, have a new breeding pair take possession of the territory, yet still manage to fledge them. As much as I respect her determination, I do not like her odds.  

After my report of continued decline of the former breeding male from three days ago, Linda and Kevin Grenzer visited Arrowhead yesterday. They found the same cast of characters that I had seen two days before — the skulking, incapacitated male, the confident new pair, the plucky old female, and the banded chick that she had been feeding — but, incredibly, Linda also turned up the unbanded chick that we had not seen on two previous visits and had given up for dead. In fact, Linda got a series of photos of this chick as it followed its wounded father onto shore (see featured photo at top). It is touching to observe the chick’s dilemma — sitting awkwardly and reluctantly on land, yet refusing to abandon its fading father. I guess if we are looking for a positive from the recent events at Arrowhead, it is that the family is doggedly sticking together in the wake of a gut-wrenching calamity.