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The Cycle of the Common Loon (Brochure)

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The Cycle of the Common Loon (Brochure) ADIRONDACK LOONS AND LAKES FOR MORE INFORMATION: NEED YOUR HELP! lthough the Adirondack Park provides A suitable habitat for breeding loons, the summering population in the Park still faces many challenges. YOU CAN HELP! WCS’ Adirondack Loon Conservation Program Keep Shorelines Natural: Help maintain ~The Cycle of the this critical habitat for nesting wildlife and 7 Brandy Brook Ave, Suite 204 for the quality of our lake water. Saranac Lake, NY 12983 Common Loon~ (518) 891-8872, [email protected] Out on a Lake? Keep your distance (~100 feet or more) from loons and other wildlife, www.wcs.org/adirondackloons so that you do not disturb them. The Wildlife Conservation Society’s Adirondack Going Fishing? Loon Conservation Program is dedicated to ∗ Use Non-Lead Fishing Sinkers and improving the overall health of the environment, Jigs. Lead fishing tackle is poisonous to particularly the protection of air and water loons and other wildlife when quality, through collaborative research and accidentally ingested. education efforts focusing on the natural history ∗ Pack Out Your Line. Invisible in the of the Common Loon (Gavia immer) and water, lost or cut fishing line can conservation issues affecting loon populations entangle loons and other wildlife, often and their aquatic habitats. with fatal results. THE WILDLIFE CONSERVATION SOCIETY IS Be an Environmentally Wise Consumer: GRATEFUL TO ITS COLLABORATORS FOR THEIR Many forms of environmental pollution SUPPORT OF THE LOON PROGRAM: result from the incineration of fossil Natural History Museum of the Adirondacks - fuels, primarily from coal-fired power The W!ld Center plants and vehicles, negatively affecting www.wildcenter.org A guide to the seasonal Adirondack ecosystems and their wild NYS Dept. of Environmental Conservation and human inhabitants. For example, www.dec.state.ny.us cycle of Common Loons mercury accumulates up the food chain BioDiversity Research Institute and conservation concerns and can reach toxic levels in animals and www.briloon.org people. Audubon Society of New York State affecting their populations www.auduboninternational.org/programs/asny Please choose products wisely — conserve energy, recycle, and safely dispose of ~~~~~~~~~~~~~~~~~~~~~ products that contain toxins such as mercury This brochure was adapted from Maine Audubon’s and lead. “Living in Loon Territory” brochure by Mike Prescott. ~MAY-JULY~ Nest building and incubation In late May to early June, loon pairs build a nest in a protected area, often on the shore of a small island or on a floating bog mat. An ideal nest site is sheltered from wind, waves, predators, and the activities of people. Both the male and female are involved with nest preparation. Occasionally, the first nest will fail (e.g.: from water level changes or predation of the eggs), and the loons renest. Thus, loons can be observed nesting from May until late July or even ~MARCH – APRIL~ August. ~JULY – AUGUST~ The return of spring and the Common Loon The nest is constructed from nearby vegetation (e.g. Raising and protecting the loon chicks to the Adirondack Mountains reeds, grasses) and mud, and is placed just a few inches above the surface of the water so that the birds can After the loon chicks hatch, they are moved by the “The ice is out, the loons are back!” is a statement easily get on and off the nest. One or two (very rarely adults to a “nursery bay”. This is an area away from the often made by those living around Adirondack lakes three) large brown spotted eggs. The female often does nest site, with shallow water and an abundance of reeds in late March and early April. Depending upon the the majority of incubation at night, while both adults for cover. During the first two weeks of life, small distance they have to travel, the loons usually arrive tend the nest and incubate the eggs during the day. The chicks will often ride on their parents’ backs for on their “home lakes” soon after “ice-out”. tiny black downy chicks hatch in ~26-30 days. warmth and protection from underwater predators. During the early spring, Common Loons migrate from What to Look for: What to Look for: their wintering grounds to summer territories on Please be careful when boating or paddling near the The adult loons usually have one or two chicks Adirondack lakes and ponds. They spend the winter shoreline from May to July when loons are on their swimming near or between them. The devoted parents on the open ocean in subdued gray and white nests. Nesting loons can easily be disturbed, and if the spend a great deal of time catching small fish for the plumage. Just before flying inland or shortly after incubating adult is frequently off the nest, the eggs chicks. As one adult feeds the young, the other may returning to their summer territories, loon molt into could chill or be taken by a predator. When nesting, “peer” underwater, checking frequently below the their distinctive breeding black and white plumage. one adult may be out fishing alone, while the other bird surface to see what the feeding adult is doing. Males usually arrive on lakes approximately two remains on the nest. Sometimes when nesting loons are weeks before the females to establish their territories approached, they “hang over” the edge of the nest. This When the chicks are very young, one adult is always in for the summer months ahead. position serves as camouflage or enables them to attendance. The chicks become more independent as What to Look for: quickly slide into the water and distract the person or they grow, and begin to swim and fish further away from their parents. At ~2-3 weeks, their down changes During the mating season, courtship behavior is very predator away from the nest. from black to brown, then at ~7-8 weeks of age, they subtle. The pair swim and dive together, performing get gray, scaly-looking feathers. The chicks are almost quiet ritualized behaviors, such as “bill dipping” (not three months old before they have learned to fish well to be confused with territorial displays such as and are capable of flying. “penguin dancing” and yodeling primarily done by male loons). These courtship rituals reestablish the Please be aware of adult loons and their chicks if you pair bond of birds who have been mated for many are boating on an Adirondack lake. Adult loons will summers. Current research indicates that warn you away with tremolo and yodel calls. If you approximately 80% of these long lived (20 to 30 see “penguin dancing’ you might indeed be the cause. years) birds return to the same territory and have the same mate year after year. Please back away and observe from a distance. Please observe loon behavior from a distance Please stay well away from loon nesting areas Loons are especially territorial with chicks, during the breeding season. and observe nesting birds from a distance. and very protective parents. ~SEPTEMBER – OCTOBER~ What to Look for: Fall returns and loons prepare for departure On Adirondack lakes in late fall, Common Loons The chicks grow very fast, and, by two months, they begin to migrate. Often adults will gather and feed change into their juvenile gray feathers. They retain together on larger lakes in “rafts”. Loons migrate in this coloration after they migrate to the ocean in the small groups or as individuals. Some loons wait for fall. They live on the ocean for two to four years the last moment before “ice-up” and begin their mi- before returning to the Adirondacks to establish a gration in late November or December. breeding territory of their own. Loons need to run on the water for several hundred By 11 or 12 weeks of age, they can feed themselves yards to get airborne. However, once in the air, they and begin to fly. The chicks experiment with short, are very powerful and fast fliers. Some birds fly to practice flights up and down the lake, and then take ~NOVEMBER – MARCH~ the Atlantic coast in a matter of hours, making a trip longer flights to other lakes. As the chicks increase of close to 200 miles in less than a day. Others stop at their independence, the adult birds socialize more with Migration from the Adirondacks - large lakes or rivers along the way, before finally other loons, and may be seen in social groups or life on the wintering grounds making it to their winter’s destination. You can fol- “rafts” on other lakes. The juvenile loons are often left low the migration of some Adirondack loons on the The Common Loon summering on Adirondack lakes for extended periods of time to fend for themselves. Adirondack Cooperative Loon Program’s website, spends the winter on the ocean. Adult birds migrate www.adkscience.org/loons. The adults begin to molt into their winter plumage by in late fall to their wintering area along the Atlantic late October, losing their coast. Juveniles journey to the ocean after the adults, If you go south during the winter and are near the distinctive black and usually waiting until the lakes start freezing up and coast, you may see the same loons you saw during white coloration. Their they have to move elsewhere. the summer in the Adirondack Park. However, look feathers are often found for birds in a gray, dull plumage instead of the more The loons must adapt to living on saltwater for the floating on the surface of striking black and white breeding coloration usually winter months. Like many other ocean-living birds, Adirondack lakes after a associated with loons. Other species of loons, such as they excrete salt though a gland in their nasal preening session.
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