To: Journey North
From: David Evers
Dear Students,
You were asked how I might capture a healthy loon on the wintering grounds, and you may be surprised to hear our plans. But first, let's see what some of you had to say:
Rachel Kramer from Ms. Heilman's class(nheilman@oak.kcsd.k12.pa.us) said "I think Dave will capture a loon by sneaking up behind it while it's sitting on its nest, and catching it in a net. Then he will put it in a cage so that he will be able to move it wherever he needs to. " And one of Ms. Ramolae's students, Tom, grade 6, Robbinsdale, MN (bramolae@metro2.k12.mn.us) said"I think Dave will set up a cage and put some food in it, and when the Loon goes into the cage the door will shut and the Loon will be locked inside."
Most winters a dozen or so healthy loons are brought into rehabilitation centers. These loons have landed mistakenly on wet surfaces such as parking lots, which look to the loons like a lake or pond. Once the loons land they can't take off again! Loons need about a 90-foot water runway in order to fly. On pavement these poor birds can hardly walk! Therefore, when people find them they're brought into rehabilitation centers and then set free.
Pavements aren't the only hazards the loon faces in their wintering grounds. I also wanted to let you know a little bit about another risk they may face. By now most adult loons have finished molting. Just 4 weeks ago they were flightless for about 2-3 weeks while their new feathers developed. This is the time when loons are in greatest danger.
Since they are using all their energy stores they are less able to deal with diseases. If they have chemicals in their body these chemicals may become more toxic as they expend all their energy toward growing in their feathers. (There are 11 primary feathers and 22-23 secondary feathers on each wing-- that's a lot of feathers and their big!) If they get sick from the chemicals sometimes they are more likely to get sicker from different diseases such asaspergillosus (this is a little fungus that floats around in the air). Their new breeding or alternate plummage is now in good shape for their spring migration.
We're still waiting and hoping to hear any day from Barb Suto of Seacoast Seabird Sanctuary near Tampa Bay that a healthy loon has been found. We have struck out so far, so within the next couple weeks we are planning to capture a wild loon on the ocean. This has never been attempted.
Our capture process during the summer is on inland lakes. To capture adults they need to be accompanied by a chick. Once we know the loon family's whereabouts we wait for nightfall. The darkness hides us as we approach the loon family using strong spotlights. The loons can't see us because of the bright lights in their eyes. While we are approaching them we also use tape recordings and give our own vocalizations to trick the loon into thinking there is another loon ahead. This usually works. When we get close to the loon family, we capture the loons with a long-handled fish net and then bring them back to shore. After banding, taking blood samples, and weighing each loon we then release them from shore. Most loons are in hand for 30 minutes. In a future report I will give you data about where the birds were banded and recovered.
We're hoping that this same procedure works on the ocean. Although the loons are not accompanied by chicks, maybe their curiousity will permit a close approach by us at night. We'll see. Right now, my field assistant, Pete Reaman, is exploring and scouting a suitable site, somewhere in the Sarasota area (south of Tampa Bay). I would rather be in a bay than out in the open ocean. Ideally, we will find a group of loons in a small bay just before darkeness and then make a capture attempt. If this works, we will then contact our veterinarian specialist, Kevin Kenow, and fly him down from Wisconsin to help attach the radio transmitter.
I hope to provide good news on the next report.
Regards,
David Evers
The Next Loon Migration Update Will be Posted on March 14th.
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