Eric Hanson, a biologist for the Vermont Loon Conservation Project, will give a natural history talk at this year’s Northern Woodlands Conference. The Loon Conservation Project is a joint program administered by the Vermont Center for Ecostudies and the Vermont Fish and Wildlife Department. We tracked Hanson down and asked him a few questions about loons.
You’ve been studying common loons since 1992. How did you get interested in loons, and what are the practical/logistical challenges of working with this species?
I spent my youth and college years participating and leading wilderness canoe trips in the Boundary Waters Canoe Area in northern Minnesota. I knew next to nothing about loons at the time, but they’re part of the lake country and one just becomes fascinated by them. I’m lucky with my work in Vermont because 80 percent of Vermont’s lakes are within a two-hour drive of my home. In my early loon research, I’d live in a tent for three months at a time traveling across Michigan, Wisconsin, and Minnesota. When doing banding and rescue work, most of it is done at night, which makes for an interesting sleep schedule.
Any funny anecdotes about those early days?
We worked with the Earth Watch organization where people joined us for night capture work. Dave Evers of the Biodiversity Research Institute – the guy who figured out how to capture loons reliably – accidentally netted two adults in a large salmon dip net and then proceeded to place them in the laps of two 70-year-old ladies who were there to help extract the birds from the net. It was a bit more than they expected, but I scrambled up from the rear of the small motor boat that I was driving and we removed the birds safely.
Do you have any suggestions for a good book on loons?
Judy McIntyres’s The Common Loon – Spirit of the Northern Lakes is still the most comprehensive book out there even though it was written in the 1980s before all the banding and newer behavioral work was conducted. Dr. Walter Piper has been studying thousands of color-banded loons in a 100-lake area in Wisconsin for the past 20 years and his website has lots of great “new” information about loons: loonproject.org
A Northern Woodlands staff member recently saw a display at a museum claiming that loons existed approximately 65 million years ago...that can’t be right. How old is the species exactly?
I think the current thinking is that loons have been around, looking very similar to the way they do now, for about 16 million years.
Loons nest right on the water...how much of a risk are boat wakes to eggs and chicks?
Most nests are either on islands or in marshes and usually in locations where they are not exposed directly to waves from wind. This usually means that the nest location is not directly exposed to large expanses of open water where the motorboats go fast. There are always a few nests that could be vulnerable to being washed out, but it has not been a major problem. Kayakers and canoers are more of an issue because they cause loons to leave the nest when they paddle close by.
You often see loons near boats and docks. Is this just a symptom of limited waterfront, or are they fairly tolerant of people?
They can be very curious, especially in May and June when they have not seen people or dogs near the water as much. They are also more territorial at this time so they might be checking out who’s visiting their “house.” When they have chicks, they often become alarmed a bit sooner if people approach.
How many chicks can loons successfully raise in a year? What are the major predators and other threats?
One or two. I’ve read about three chicks being raised, but have never observed that in my 20 years of loon work. We had our first confirmed instance of a bald eagle taking a loon chick last year, and I’m sure we’ve lost a few others that way. Snapping turtles and big fish will take a loon chick, as well. Chicks are often lost during territorial battles, either being killed directly by the intruder or because they are neglected while the parents defend the territory.
We’re also wondering about loon parenting behavior. It seems like both male and female are attentive. Are there differences in behavior between the parents?
There was a detailed study of this by Dr. Jay Mager back in the 1990s where he followed color-marked loons for 4,500 hours over two summers documenting every behavior the loons performed. On average, males and females shared equally in every behavior except one: males rested two percent more with the young than females. Otherwise, feeding, preening, exploring, defending were all conducted equally by the male and female within a loon pair.
Are you the recipient of a lot of loon-themed gifts (can openers, refrigerator magnets, loon socks), and if so, do you keep them?
Unlike my Aunt Cathy back in the Midwest, I’ve avoided the overload of loony house items. I’ve received two gorgeous prints and a carving, which is just about right. I wish VCE could receive a five percent surcharge on every loon item sold and every time a loon brings a happy thought to someone. I might not have to fundraise as much.
How is the loon population faring across the Northeast?
Really well, overall. Populations are stable or increasing in all the northeastern states. But we still have concerns, including the disappearance of territorial loons on several very large lakes in New Hampshire and Maine while nearby small ponds appear stable. Fishing gear is still causing mortality despite several lead fishing gear bans. We’ve also observed a possible uptick in disease mortality including a fungal disease, bird flu, and even one case of malaria.
We hear a lot about loons dying after ingesting lead sinkers and shots, and yet we know they eat fish and other live, animate prey. Why are they ingesting sinkers and BBs? What do they think they’re eating?
Loons ingest small stones to help digestion in the gizzard, thus they might be picking up lead sinkers thinking they are stones. They also will take live bait and lures, and will even take a small fish on an angler’s line. Easy pickings.
Have the public relations campaigns urging sportsmen to use steel shot and sinkers had any discernable effect in reducing loon mortality?
Slightly. We’re still collecting and assessing all the dead loons reported and sending them to Tufts University or a UNH lab for necropsies. Two years ago we had three loons die from lead poisoning despite a ban on the sale and use of small lead sinkers. Jigs and large sinkers are still permitted in Vermont. The Loon Preservation Committee in New Hampshire has the largest data set and it seems lead mortality of loons has decreased slightly since legislation was put in place in the early 2000s, but we see both rises and falls in this rate over the years.
What can people do to promote loon nesting success?
Avoid the nesting areas if you know they are present. We over-use nest warning signs in Vermont in part because our lakes are very busy and we have lots of volunteers to help take care of them.
Vermont Center for Ecostudies is well known for using citizen science to collect data on bird and insect species. Are there opportunities to volunteer?
People can help out as much or as little as they’d like; some report on a single visit to a single lake, others check in on a loon pair every day all summer. You don’t need to know the differences between all your warblers and sparrows, so monitoring loons can really be for anyone, even if they have limited bird knowledge. It helps if people have a boat of some kind but even that’s not always necessary. You can learn more on our website.
There was that recent movie on Ant Man, and we hear that Squirrel Girl is in the works. If “Loon Woman” were a superhero, what would be her special power?
I think she could be cross between Aquaman and Wonder Woman, as loons are amazingly fast and agile swimmers and fliers.
Don’t miss Eric Hanson at the Northern Woodlands Conference. Enroll now!