I am still shaken by the recent spate of fishing entanglements. Perhaps my sadness and vexation over these troubling events prevented me from looking clearly ahead. I thought: “Well, the hooked female at East Horsehead will die slowly from the ingested lure, and that will be miserable, but another female will settle on the lake and replace her.” I gained some measure of relief from anticipating the orderly progression of events that would unfold on the lake. As expected, the afflicted female, “Iceberg”, has declined, although she is still not yet weak enough to catch. Her mate, “YellowBlue”, has not stuck to the script, however. Far from waiting passively for another female to settle with him, YellowBlue is proactively seeking a new territory. And that is the problem.
It should have been obvious to me when Nelson reported, last Wednesday, that he saw YellowBlue intrude onto nearby Alva Lake. Females leave their breeding lakes occasionally to intrude onto the neighboring territory; males do so rarely in the height of the breeding season. So YellowBlue’s intrusion was a sign that something was afoot. But I dismissed his visit as an anomaly — the distracted antics of a male whose mate was unwilling to initiate a nest. As it turned out, YellowBlue was probing neighboring lakes for a weak spot, a territory whose owner he could defeat in battle and whose territory he could seize. Based on the aggression and chasing that occurred when YellowBlue visited Alva, the Alva male was not on board with this plan.
But YellowBlue’s search continued. In the next few days, he found a vulnerable male on a different neighboring territory: West Horsehead. We were not present to observe the entire sequence of events, but Al Schwoegler reported yesterday that CopperGreen, the West Horsehead male, was skulking about and hunkering down at the northern end of the lake, far from the nest that he had built with his mate (a 28+ year-old female, “WhiteYellow”, who is among our oldest birds). A quick look at the middle of the lake explained CopperGreen’s diffidence. YellowBlue was foraging and resting there, acting like he owned the place. (Melanie confirmed that this state of affairs continued today.) Now loon behavior in many ways is unsubtle, and territorial behavior is a good example. When a loon is in the middle of a lake, acting like he owns it, he owns it! So YellowBlue had clearly battled CopperGreen, defeated him, and forced him to lay low along the lake’s periphery to escape further attacks. We have seen this sequence of events scores of times. If events proceed normally, WhiteYellow will ultimately cease her efforts to incubate the eggs alone, and the nest will be abandoned. Perhaps WhiteYellow and YellowBlue will renest again this year, but that is doubtful. (CopperGreen, if he is healthy enough, will fly to a nearby undefended lake, like Bearskin, where he can lick his wounds.)
What is troubling about this latest turn of events is the central role played by humans. That is, an angler — a careless or perhaps just an unlucky one — hooked Iceberg on East Horsehead and fled the scene. Iceberg immediately ceased breeding behavior and began a struggle to survive. This turnabout forced her mate, YellowBlue, to go with Plan B, leaving his lake to find another nearby with a healthy female on it. In leaving his own territory and evicting a male on West Horsehead that was sitting on eggs, YellowBlue likely doomed both East and West Horsehead to breeding failure in 2017. So a single fishing casualty affecting a single adult loon has precipitated the loss of breeding opportunities on two of our most productive lakes.
While we are concerned for the impacted loons, this latest eviction has some scientific value. YellowBlue is quite a phenomenon — the youngest male ever observed to evict an established male from his territory. Hatched on Little Bearskin Lake, YellowBlue is only four years old. Perhaps it was his good fortune that CopperGreen was himself only six years old (a product of Oneida Lake). So the YellowBlue-CopperGreen contest featured the youngest combatants ever. I hope that the novelty of this latest encounter takes away a bit of the sting from the event that set it in motion.
All is not lost among loons this year. In fact, one advantage I have, as someone who tracks breeding behavior on 120 lakes, is the capacity to shift my attention away from those where things have gone south to lakes that where all loons are healthy and productive. So let me end with a beautiful photo of Linda’s from Muskellunge Lake that will remind us that there are lakes where loons are free of hooks, where they defend their territories successfully, and where the next generation thrives.