The loons are back in town
Even though the ice was slow to leave the lakes this year, it's finally starting to feel like summer.
I've been hearing the loons as they're returning back to their lakes. There's something about hearing loons echoing over the water that is so Minnesotan. On March 13, 1961, Governor Elmer L. Andersen signed the legislation that adopted the common loon (Gavia immer) the official state bird of the State of Minnesota.
This year, people have been worried about our loons returning due to the oil spill in the Gulf of Mexico. Loons are migratory birds, and since our lakes are ice-covered in the winter they are not able to stay here and find food. In this article, I'll update you on the latest news about loon movement and what we know so far about the effects of the gulf oil spill.
Some Minnesota loons winter off the Atlantic coast from North Carolina southward to Florida, but more winter along the Gulf coast from Alabama and the Florida panhandle southward along the western coast of Florida to the Florida Keys. The areas along the gulf are having problems with oil washing ashore. Loons have no defenses against oil and do not recognize a sheen of oil on the water as a hazard.
At this point, we don't know the extent of the threat or what percentage of our loon population could be lost to the oil spill. As this spring progresses, we will know more as people notice if loons return to their lake or not.
In my observation this spring, I have seen or heard about loons coming back on numerous lakes in the Detroit Lakes and Fergus Falls areas. In addition, I have heard loons back on Leech Lake in Walker. This is promising.
This year, two adult loons in Minnesota are equipped with satellite transmitters and geolocators in an effort to study the movements and foraging patterns of fish-eating birds while they migrate through the Great Lakes.
You can track the movements of these loons by visiting this DNR website: ttp://www.dnr.state.mn.us/eco/nongame/projects/loonsgulf.html.
Minnesota has the largest summer population of loons in the lower 48 states, and approximately three quarters of the common loons in the Midwest. The DNR estimates the total Minnesota Loon population to be around 12,000 adults. The DNR has a Loon Monitoring Program, and each year volunteers collect information on common loon numbers on more than 600 lakes distributed among six regions, or "index areas" of the state.
One of the index areas is central Becker County, and loon populations have slightly increased in this area over the past 13 years. In this Becker study area, there are an estimated 1.6-2.5 adult loons per 100 acres of lake. In the Otter Tail area, the loon population has not changed, and there are an estimated 1.3-1.9 loons per 100 acres of lake.
Since loons are diving birds that use their eyesight to capture their food, they need clear water and healthy fish populations. This is why they are used as an indicator for lake water quality. Also, loons only nest on undisturbed shorelines or islands with plenty of natural vegetation. They need tall shoreline vegetation for protection of their young.
Larger lakes and longer shoreline are associated with more loons. Because loons nest at the waters' edge, they are easily disturbed by excessive boat traffic and wakes, and are displaced by human residential activity. If you are out boating and see a loon, keep some distance between you and the loon so you do not disturb it.
To read more about loons, you can visit the DNR website: http://www.dnr.state.mn.us/birds/loons/index.html.
Moriya Rufer is the Lakes Monitoring Program Coordinator for RMB Environmental Laboratories in Detroit Lakes, 218-846-1465, firstname.lastname@example.org.