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We have been out all night for the past week capturing and marking adult loons and chicks. It is tiring work. Last night, for example, we had to carry our 14 foot motorboat off of a highway shoulder and into Sunday Lake. Next, we hefted it down a long flight of steep stairs, out a long narrow dock and into a marsh to reach the Minocqua-Huber Bay territory. My back still aches! But these visits were productive. In both cases, we captured a male hatched in the study area, his unmarked mate, and their two chicks. So our strenuous efforts were rewarded. (The Sunday male is a fifteen-year-old who was hatched on Seventeen Lake; the Minocqua male is only six and was reared on Brandy Lake.)

Our third lake of the night has a public landing. It was a breeze to back the trailer up and slide the boat into the weedy, pike-rich waters of Little Bearskin Lake. For a change, we were not sweating profusely and breathing hard as we began our improbable search for the pair and their young. However, we were not prepared for what we discovered.

The visit began routinely. We motored slowly to the middle of the lake to listen for the birds, as we often do. Within a minute, a bird wailed in the southeast corner. We were thrilled, because we seemed to have found the family quickly. The loon that had called was, in fact, only the female from the pair, who had wandered off separately from the male and chicks. Nevertheless, she responded strongly to our chick calls and was easy to scoop out of the water. As we removed her from the capture net, we were alarmed to find that she had a fishing lure and monofilament line wrapped tightly around her left leg.

Fishing line is unkind to wildlife. The very properties that make it attractive to anglers — its strength and thinness — give fishing line the ability to cut deeply and mercilessly into the flesh of animals unfortunate enough to become entangled in it. As the photo above shows, the female’s left leg was tightly wrapped, and a lure and hook had become attached to her leg.

Linda was able to cut away the line that had pierced the scaly, keratinized outer layer of the female’s left leg (see video below) and remove the attached lure. We are concerned about the raw tissue that was exposed by this piercing, but Linda applied antibacterial ointment, and we are hopeful that she will recover.

An injury to any loon is painful, but this one was doubly so. This mother of two chicks is the second oldest loon in our study area. She is at least 31 years old! First marked in 1996 on West Horsehead, she raised 19 chicks with three different males on that lake but was evicted in 2018 and fell off of our radar. We were delighted to see that she had resettled on the very productive Little Bearskin territory this spring with the 18 year-old male there. The two healthy chicks she has raised with him provide further evidence that females retain the ability to produce young during their later years.

But we worry. At 3500 grams, she is 250 grams or so lighter than when we captured her several years ago. This, the fact that she had left the male to care for the chicks last night, and the odd not-quite-wails that she uttered after we released her might indicate that she has been compromised by this angling injury.

In fact, she and we were extraordinarily lucky. Most “off-chick” adults — those not tending their chicks — are difficult to find at night and capture. Only the fact that we stumbled into her before we found the male and chicks allowed us to catch her, free her from the tightly-wrapped fishing line, and treat her injured leg. Now, at least, she has a fighting chance to resume her parental responsibilities, regain lost weight, return to her Florida winter quarters — and perhaps return again in 2022.

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This is a frantic time of year for wildlife and wildlife rehabbers. Why? Because while you are ditching Weird Aunt Beatrice at your family reunion, loon pairs and their chicks must dodge your crazy nephew Lucas on his Jetski. Needless to say, loons have considerably more on the line.

The tranquility of May did not prepare the Tomahawk-Kemp pair — or me — for the life and death struggle they would face in July. On May 11th I ran across the super tame male and female from Tomahawk-Kemp when they were preparing to nest in the long channel between Minocqua and Tomahawk. On that visit, they seemed almost to welcome my presence, and it was a simple matter to scribble down all of their colored leg bands as they rested and made short dives near my canoe. I experienced one of those moments when you are alone with nature and feel a sudden, ineffable connection with a wild animal. I wondered: “Does the male remember me from 17 years ago, when I first encountered him as a settler on South Two Lake?”

The Tomahawk-Kemp pair’s recent experiences with humans have been considerably less pleasant than those in May. We do not know the whole story, but on about June 17th, the pair hatched two chicks. (Judith Bloom, whose June 20th photo appears above, helped us narrow the dates with her routine checks.) Having survived black flies, raccoons, eagles, and curious humans to hatch both eggs, the Kemp pair headed out into the main body of Tomahawk to locate small fish suitable for their ravenous youngsters. There they began the daunting task of diving to catch food for the chicks, while at the same time helping the tiny fuzzballs steer clear of boat traffic. Most boaters adhere to local ordinances with respect to speed, distance from shore, and respect for wildlife; some do not. We suspect that a boater in the latter category ran down – either purposely or not – the Kemp hatchlings on the 1st or 2nd of July. The parents were unscathed; adult loons can dive rapidly and deeply, and those living on Lake Tomahawk have ample experience avoiding motorboats. Young chicks, however, have neither the diving capacity nor the familiarity with speeding watercraft to help them escape collisions.

Both chicks were hit by the boat. Linda Grenzer snapped the photo below of the less severely injured chick; it showed a healed wound towards the tail end, near the base of the left leg.

LMG 26251 Lake Tomahawk Kemp Injured Chick

The second chick looked better externally but had internal damage from the boat strike — a ruptured air sac — which prevented it from floating upright in the water. (Bird’s air sacs are thin membranes that connect to the lungs and are part of the respiratory system.)  So Linda, Elaina, and Kevin decided to catch this listing chick and take it to REGI for treatment. Fortunately, REGI repaired the damage, fed the chick well, and prepared it for successful release three days later. As you can see from Linda’s photos at the release, both pair members quickly accepted their missing youngster.

LMG 26337 Lake Tomahawk Kemp Rehab Chick Release

On the other hand, its sibling had apparently enjoyed being an only and had mixed feelings about the reunion!

LMG 26278 Lake Tomahawk Kemp Rehab Chick Release

According to recent reports, all is now well with all four members of the Kemp family. Life will continue to be a wild ride, because boat traffic will not wane for several more weeks, and the siblings will no doubt bicker over food from time to time. Since chicks rapidly improve their diving skills, though, we can hope that these two have had their last close encounter with fast-moving watercraft.

 

 

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Loons are always with me. With its fires, mudslides, and Mediterranean climate, southern California could hardly be more different from northern Wisconsin, but the loons winter here. I see them at Newport Pier, a bustling wharf that juts out into the Pacific and draws scads of Vietnamese anglers…..and me. The chattering fishermen are after pacific mackerel, which feed beneath the wharf in great whirling clouds. I am looking for pelagic birds that might fly by, like red-footed boobies, pomarine jaegers, and common murres. But I always see loons too. In fact, common, pacific, and red-throated loons all occur along the coast of southern California in good numbers.

My first sighting this morning was auspicious; I spotted a fast-flying parasitic jaeger as I reached the end of the pier. Small pods of common dolphins surfaced at intervals as they too pursued mackerel, exciting the gulls and pelicans near them. Great rafts of western and Clark’s grebes stretched out north and south of the pier. Experience told me that these circumstances were likely to produce a rare bird sighting.

As I completed my initial scan of the water adjacent to the pier, I saw a common loon with a buoy near it — at least, the odd dayglow-pink item near the loon registered as a buoy on my first glance at it through my spotting scope. (A photo taken with my phone through the scope appears above.) As I studied the loon and pink item further, I realized it was a bobber connected to one of the legs, because it followed along a foot behind and bobbed up and down rhythmically as the bird swam slowly along the surface. I groaned. Even in winter, apparently, loons face fishing entanglements.

My relaxing birding trip at an end, I watched the loon for an hour to learn how it was coping with the fishing gear. Fortunately, it swam southward during this period, which, bit by bit,  brought it closer to the pier. Despite the cheerful fishermen whose casts and puttering about blocked my view at intervals, the loon was simple to track. Early on, another common loon approached and preened within a few meters. The entangled loon remained alert but showed no other obvious response. Similarly, it ignored a smaller pacific loon that came near while diving. A second common loon came over and showed a hint of social behavior, such as we see in the breeding season. For a third time, the loon with the bobber made no response. The bird did not even react noticeably when a juvenile western gull flew over, settled beside it, and began to pick at the bobber. At all times, the entangled loon sat high in the water; it never dove, preened, or even gave a wing flap.

The lack of social interaction, disinclination to dive or exhibit other normal loon behaviors, and posture of the loon in the water speak volumes about its condition. These signs indicate that it has probably been dragging the unwanted bobber for some days and is severely impacted. Fortunately, bald eagles, the loons’ nemesis during summer, are rare in southern California, so the loon is not likely to succumb to predation. But its inability to dive means it has already begun to lose weight and become weak. It will surely starve if the bobber is not detached soon. I will visit the pier tomorrow to see if I can relocate the bird. If so, and if its status appears unchanged, I will see if I can put together a capture team. With great luck, we might free the doomed bird.

 

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As my family and friends will tell you, I am judgmental. When an event happens that could be attributed to mindless error, I am inclined to view it, instead, as deliberate selfishness or irresponsibility. I derive my hypercritical worldview in part from my profession. As a behavioral ecologist, I presume that much of the behavior we see in animals (including humans) has evolved in order to promote their evolutionary fitness. Put another way, I assume that a good deal of animal behavior is selfish — evolved because it allowed the ancestors of living individuals to survive better and leave more offspring than others of their species.

The presumption of selfishness is a helpful touchstone in my field. It provides a starting point when one is interpreting a new and unexpected behavior pattern. For example, if I notice a new soft call emitted by female loons during courtship, I am apt to hypothesize that this call might help mates synchronize their breeding activities so that each will be prepared to do its share of the incubation duties, once eggs are laid. (Such synchronization, which involves rising prolactin levels in the blood, has proved crucial to successful breeding in many species of birds.) So the presumption of selfishness can  be a useful prism through which to understand animal behavior.

A week ago, the folks at REGI learned of an event that pushed even my cynical viewpoint to the limit. Following a report from a lake resident, they found an injured loon on Metonga Lake, which is just south of Crandon, Wisconsin. After Linda and Kevin Grenzer captured the loon (pictured in Linda ‘s photo above) and the REGI team examined and x-rayed it, they learned that it had been shot at close range with a shotgun and had lead shot throughout its body. Despite efforts to save the unfortunate shooting victim, it died in their care. The story might have ended there, except that the loon was banded.

Since Metonga is outside of our study area — some 20 miles east of our southeasternmost lake — we do not know the lake at all. Sleuthing by Linda and me revealed that this oval 2000-acre waterbody supported two breeding pairs in 2018. According to the loon ranger, both pairs hatched chicks this year, although only one of the pairs fledged their two hatchlings. Most important, neither pair contained a banded individual. Thus, the shooting victim was not a member of either resident pair.

Some of the circumstances surrounding the tragic shooting make sense. As many of you know, breeding loon pairs become restless in September and October, often leaving their territorial lakes. Moreover, large, clear lakes like Metonga are favorite spots for wandering adults to visit, as they forage intensively and lay down fat stores to fuel their southward migration. So it is not at all surprising that a breeding adult from a neighboring lake — as we presume the victim was — would be found on Metonga. Finally, virtually all of the loons that we band that show up that far from our study area are females, because females are the more dispersive sex. (On average, females settle 24 miles from their natal lake, while males settle 7 miles from their birthplace.)

The identity of the shooting victim allows us to speculate about its tragic end. When I looked up the band colors and partially-obscured USGS band number that Linda provided, I learned that we had banded this female nine years ago as a chick on Bear Lake in Oneida County. We have not seen her since. The father and mother of this female were among the most approachable loons in the study area. (The male still holds the territory there, as he has since 2001 or earlier.) As Chapman student Mina Ibrahim showed a year ago, tameness (the minimum distance that a resting loon will permit a canoe to approach before diving) is similar between parents and offspring. So it is almost certain that the dead female was a tame individual, like both of her parents.

If our simple inference is correct, then this incident has exposed one hazard of extreme tameness in loons. While the vast majority of humans who approach loons closely are merely curious and would never dream of harming them, an occasional human might do so. It is easy to reconstruct the chain of events that led to the shooting. In the opening week of duck season, a hunter got an easy shot at a duck-like diving bird and took full advantage.

This analysis might well be correct, but it has one hitch. Loons are so well-known across the heart of their breeding range that they can scarcely be confused with ducks. None of the species of ducks that a hunter in northern Wisconsin would be looking to bag is patterned much like a loon. Furthermore, all duck species in the area are far smaller than loons and are prone to fly, not dive, when approached by humans. And since we know that the hunter blasted this loon from very close range, it is even more difficult to believe that the incident arose from a misidentification.

Call me cynical, but I believe that the hunter who killed this loon was not foolhardy, as generous and forgiving people might believe, but rather purposely wicked. Of course, this conclusion further erodes my opinion of other humans. What kind of person deliberately shoots a loon?

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Last year I wrote a blog post in which I concluded that late-hatching chicks returned at a rate no different from early-hatching chicks. I found the result surprising, as one would expect early hatchlings to have a head start in learning to feed themselves, honing their flight skills, and preparing for their first migratory journey. The photo and story I got from Linda Grenzer a few days ago has forced me to wonder if I need to collect more data on this question.

The breeding pair on Squaw Lake had an eventful year in 2018. Delayed, like all other pairs, by the late thaw, they initially nested along the shoreline near the boat landing. After a predator snatched both eggs off of the nest, they nested again not far away. This time they were more fortunate; the eggs hatched, but not until about July 22. When we captured the family on August 3rd, we found the chicks almost comically small — two little puffballs that did not approach the size of the many other juveniles we had encountered. Chicks are cute in their first few weeks, and we enjoyed observing them and handling them cautiously while giving the female a new set of bands.

Our delight at seeing the adorable chicks was tempered by the fear that chicks hatched so late would not mature in time to complete the southward migration. The fear is justified; parents must balance the energetic demands of their demanding offspring against their own need to maintain good body condition and prep for their autumn journey. Inevitably, adult loons spend progressively less time on their home lake in September as they forage intensively, molt into drab winter plumage, build up fat levels, and, in late October or early November, head south. This goes for parents and non-parents alike.

So it was not surprising to get a report from Linda that the Squaw adults had left their breeding lake, leaving their late-hatched chicks to fend for themselves. What was alarming was that one chick had chased someone’s jig, managed to hook itself above the base of the bill, and was no longer diving or foraging normally. Further evidence of its desperate condition was that it was not difficult to capture and weighed a mere 1750 grams — roughly 1 kg less than it should have at 9 weeks. Following an X-ray at Raptor Education Group, Inc. in Antigo, the chick was found to have swallowed a second hook from a separate encounter with an angler.

Since we have long since ceased our routine visits to study lakes, we can only speculate about the series of events that put the chick in this bind. Marge Gibson of REGI suspects that, without parents to help it satisfy its foraging needs, the chick was struggling to feed itself. In its desperation, the chick began to attack fishing lures until the hook in its cheek and weakness conspired to incapacitate it.

If Marge is right, and late-hatched chicks are sometimes left with too little feeding capacity to maintain themselves, then this pattern should show up in our data. Specifically, we should see fewer very-late-hatched chicks return as adults to the study area. This plausible scenario will fuel another round of data analysis…when I find time!

To end on a positive note, the angling victim is bouncing back at REGI and feeding voraciously. If you do not believe me, look at this video from the REGI website.

https://www.facebook.com/RaptorEducationGroupInc/videos/470615703434171/

If it continues to thrive, the REGI folks will face another challenge: what to do with a healthy juvenile, but one whose stay in captivity and recovery made flight practice impossible.

 

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In my last post, I told only half of the story of the explosion of the Cunard family — the cheerful half. If you read that post, you know that, following the eviction of the Cunard male and abuse or neglect of the chicks by the evicter, one chick made a daring 1/4-mile trek across land to Hasbrook Lake and is now happily ensconced in that loon family.

The other Cunard chick was not so fortunate. In fact, following interviews of campers and the camp steward, we now know that a day or so before the eviction that led to the desperate dash of one chick to Hasbrook, its sibling had swallowed the live bait and hook used by a camper. As he described it to me, the fisherman panicked and did what most do when they have hooked a loon: he cut the line. I discovered the aftermath of this hooking. The thoroughly consumed remains pictured above suggest that the injured chick became weak, took refuge on shore (as seriously injured loons do), and was attacked and killed by an opportunistic mammal or scavenged after death. Its four leg bands confirmed its identity; the threaded line and fishing snap I found confirmed the cause of death. So the eviction that occurred on July 30th and 31st was actually the second unfortunate turn for the Cunard pair during the last three days of July.

We have discovered several such hookings during our study, despite the fact that anglers do not trumpet them. Perhaps we should take a moment to describe what to do when a loon takes your hook. The best outcome is removal of the hook by the fisherman. Removal of the hook gives the loon a good chance to survive the encounter. Cutting the line, on the other hand, frees the angler but leaves the hooked loon with a death sentence. A hooked loon (or other animal) on the end of a cut fishing line has to contend with a hook or lure that it probably cannot dislodge on its own. Its feeding impaired or prevented altogether, a hooked bird will probably succumb to starvation or predation resulting from its weakened condition. The second best outcome is to cut the line and immediately inform a local wildlife official of what has happened so that he or she can get help for the bird. In many cases, a hooked bird can be captured and de-hooked by me or someone else trained to do so. In other words, if you cut, don’t cut and run. Those of us who study and love loons will do our best to save one that is in trouble.

The Cunard chick’s death is a case in point. Had we known about the hooking, we would have had little difficulty re-capturing the chick and likely removing the hook as well. In that case, Hasbrook Lake might have ended up with four chicks rather than settling for three!

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The deformity was obvious back on May 17th, when we first saw her. The breeding female on Johnson Lake had part of her bill jutting upwards at a crazy angle. At first, viewing her at a distance, we thought that the dark spike that appeared to emerge from her bill might be a lure of some kind that she had latched onto mistakenly and been unable to dislodge. But, as Elaina’s photo shows, the distal half of her bill is bent upwards at a 45 degree angle. We were alarmed at her situation, which appeared uncomfortable, at least, and deadly, at worst.

But she behaved normally. Since we carefully observe, painstakingly describe, and publish articles about loon behavior, we habitually assess any loon’s comportment that we see according to thousands of others seen before. Her diving and foraging was normal. Far from permitting too-close approach by humans — a common red flag that can indicate severe injury — she was actually rather skittish. She pointedly moved away from us whenever we approached in an effort to look for leg bands.

Anatomically, she is far from normal. Bird’s bills consist of a matrix of bony support, covered by a keratinized epidermal layer (rhamphotheca). In other words, the displaced part of this loon’s bill should comprise not merely soft tissue but bone. Mark Pokras, associate professor emeritus at Tufts School of Veterinary Medicine, assures me that the fact that the bony foundation that should extend to the bill tip is missing means that it “will never grow back normally”. The best we can hope for, he says, is that the bent keratinized tissue — all that remains of the end of her upper mandible — drops off eventually. I was chagrined to hear this news but heartened to learn also that Dr. Pokras has, during his decades of loon anatomical study, seen about 10 cases where large portions of loon bills have been missing. These cases include a male in Maine that had only half of an upper mandible (as this female does) but that fed itself normally, held its territory, and produced offspring in multiple years.

That loons can survive an injury of this kind to a crucial feeding organ and still breed seems remarkable. I suppose their resilience might be explained partly by the  challenges they face routinely across the range of different landscapes they inhabit. That is, an animal that must locate, pursue, and capture a broad spectrum of actively-swimming prey — in water that is sometimes fresh, sometimes salty; sometimes clear, sometimes turbid, must be a flexible and adaptable creature indeed.