This article copied from the White Sand Lake Association:
In Wisconsin, Michigan and Minnesota, loons typically begin to arrive on their nest lakes around mid-to-late April. The first order of business is to establish a territory then attract a mate. This is done during the last weeks of April and early in May – then nesting begins. Most loons in Wisconsin are nesting by mid-May, which means eggs begin to hatch one month later in mid-to-late June. Some pairs that begin nesting later, or who lose their first nest and try a second time, will have eggs hatching into early July.
The first four weeks are the most critical in a young loon’s life. This is the time when they are covered in downy feathers and are unable to maintain their internal body temperature. It is when the chicks are completely dependent upon their parents, so adults spend most of their time catching fish and feeding the chicks. This is also when chicks are learning to dive, so the typical way a loon avoids danger, diving, is not an option for them. Once the young loons reach four weeks of age, they have molted into their first set of feathers and can maintain a regular body temperature, and they are able to dive and are catching some of their own food. Once the young become self-sufficient, adults begin spending less time with them, as they prepare to leave on their fall migration. The young loons stay behind until almost ice-up, feeding and gaining strength to make the southward flight themselves.
Therefore, the most important time for loons, in terms of ensuring successful reproduction, is from May through mid-to-late July. This is when adults are sensitive to intrusions at the nest site, and, later, when young are most dependent on the parents. Any sustained disturbance during the nesting season or during the early stages of chick-rearing can be detrimental to a loon pair’s nest success for that year. Because loons lay only two eggs per nest, and usually only have one or two (if the first nest is lost) opportunities to lay eggs each season, even one year of disturbance can have negative effects on an area’s loon population over the long-term.
So what can we do? All of this does NOT mean that we cannot use a lake during the prime of summer. It simply means that we have to be mindful of the fact that we share the lake with others – people and wildlife. Here are some things we can do to help loons while enjoying the lake ourselves:
Loons can be very tolerant of human recreation and even raise young successfully on lakes that have regular recreational use. But people using the lake need to be mindful of the loon’s presence and have the courtesy to give them some space. If we do this, we will be fortunate enough to have loons return to our lakes year after year, and we can be sure that the loon’s call we hear floating on the morning mists or the evening air is one of life and harmony and not a sounding of the alarms that something is wrong.
What would a trip to the northwoods be without the sight of a loon feeding in a quiet back bay or the echo of a tremolo call in the twilight? While visitors to the north can find loons on everything from mailboxes to coffee mugs, t-shirts, and placemats, finding and observing real birds is often more challenging. Here are some tips on how to observe loons while minimizing your impacts on nesting and chick rearing.
The season for loon observation in the Upper Midwest begins shortly after ice-out, usually in late April or early May. When the loons arrive in spring, their first activities are typically to establish their territories and their pair bonds. Loons are territorial birds, defending an area where they feed, nest and raise their young. Territorial behaviors include aggressive running and splashing, and an upright dance across the water- termed the penguin dance. Male loons defend their territories with the yodel vocalization. Loon pairs enhance their bond using behaviors such as bill dipping, paired swimming, nest building, and copulation.
Spring is a fascinating time to observe loons but it is also a critical time in the birds’ life cycle. People can easily disturb loons and cause nest abandonment. While loons with a history of nesting on more developed lakes can acclimate to human activities, loons on remote lakes can be very sensitive to human presence. If you are observing loons in the spring, stay 200 feet away when possible and view them with binoculars or a spotting scope. If they sound alarms such as the tremolo call (a quavering laugh) or penguin dance, you should leave the area. The best rule of thumb is to stay far enough away from the loons that their activities are not disturbed.
During June, most loons are incubating eggs. It is important not to frighten the birds from the nest during their 28-day incubation period. If disturbed, loons will slip off the nest, leaving the eggs exposed to overheating or cooling and to predators such as Bald Eagles, gulls, and raccoons. After the chicks hatch, the loon family generally moves to a nursery area. This is usually a quiet bay where the youngsters are protected from predators, excessive disturbance, or heavy wave action. Again, care must be taken so that the loon family is not stressed by human presence.
As the chicks mature, the adults will leave them on their own for longer time periods. Adults often are seen in groups during late July and August, calling and swimming in what may seem to be repetitive patterns. This is called the circle dance and biologists hypothesize that it is related to migration and staging behaviors.
Perhaps one of the most interesting times to observe loons is during migration. In fall, large groups of loons may gather, or stage on the Great Lakes or inland lakes. Adult loons begin to migrate in September, followed by juveniles in late October and early November.
Though viewing wildlife depends to some degree on luck, there are a few areas in the Upper Midwest where your chances for spotting loons are most favorable. Lakes larger than 500 acres are more likely to support loons although the birds may be more difficult to find on large bodies of water. While some lakes may be accessible by foot, a small boat or canoe may optimize your chances of seeing a loon. Binoculars, a spotting scope, or a telephoto lens for your camera are also helpful tools.
In Wisconsin, the counties of Vilas, Oneida, Forest, and Sawyer have large numbers of resident loons. In the northeastern part of the state, lakes near Minocqua, Eagle River, and Mercer are prime locations. In the northwest, the Hayward area is a good starting place. The Turtle-Flambeau Flowage in Iron County and the Chippewa Flowage in Sawyer County have the largest densities of nesting loons in the state. In the summer, it is possible to find non-breeding loons on Lake Superior, particularly around the Apostle Islands.
In Minnesota, Aitkin, Cass, Beltrami, and Hubbard counties are the most densely populated with loons. Many lakes in the Superior National Forest and Voyageurs National Park have resident loons, as well as the area around Brainerd. In fall, large groups of loons often gather before their southerly migration on Lake Mille Lacs.
In Michigan, good loon observation areas include Isle Royale National Park and the Ottawa National Forest’s Sylvania Wilderness Area. During spring and fall migration, thousands of loons pass by Whitefish Point in the eastern Upper Peninsula.
LoonWatch is interested in your loon observations. If you visit lakes in the northwoods frequently, we invite you to participate in our annual loon monitoring program in Wisconsin. There are similar monitoring programs in Minnesota and Michigan coordinated by the Minnesota DNR and the Michigan Loon Preservation Association. If you are a less frequent visitor or have limited time, please consider assisting with our five-year survey in Wisconsin. If you would like more information about volunteering, please contact LoonWatch. In the meantime we hope that you have a rewarding loon-watching experience and that you share your enthusiasm for loons with other interested citizens.
Loons have four basic calls, though there are some variations. All calls are given by both males and females, except for the yodel that can only be produced by males.
The yodel is a territorial call given by male loons. The call begins with three notes that rise slowly and are followed by several undulating phrases. It communicates to any loons in the area “I am a male loon, I’m on my territory, and I’m prepared to defend it.”
The wail resembles a wolf howl. Individual loons use this call to locate other loons. If you listen closely, you will hear a wailing loon saying, “where are you?” Indeed, that’s what they are asking.
The tremolo sounds like a quavering laugh. It is typically used when loons are disturbed. A variation of the tremolo is the flight call. It is usually given over lakes and is a loon’s way of requesting clearance for landing. If a loon on the lake responds with a yodel, the one in the air usually flies on to the next lake.
The hoot is a soft, one-note call loons use in close quarters to call to chicks, mates, or even other loons in a social flock. In social groups, the hoot can be thought of as the loon’s way of saying “hi.”
(The study of periodic biological phenomena, such as flowering, breeding, and migration, especially as related to climate. From the Greek phain?, “to show, visible, open, evident,” and -ology, a branch of learning.)
Common Loons arrive on Wisconsin lakes as soon as the ice leaves in mid-to-late April. Most loons in Wisconsin are nesting by mid-to-late May, with eggs beginning to hatch one month later in mid-to late June. Some pairs that begin nesting later, or who lose their first nest and try a second time, will have eggs hatching into early July. Loons typically lay only two eggs per nesting attempt. Nests with three and even four eggs have been documented, but are rare.
After chicks hatch, they stay on the nest for up to one day until the adults call them off. Once on the water, they are taken to a nursery area, which is usually a secluded bay or protected shoreline. Adult loons feed and protect the chicks until they can dive and catch their own food at approximately eight weeks of age. Adults often leave the chicks and form pre-migratory flocks in early August. Adults begin flying south in late August and early September. Chicks stay on the nesting lakes, feeding and taking their first test flights, until nearly ice-over. One day, they start running across the water, take flight, and head south, where they will stay until they are three years old. Most chicks return to their nesting lake (or one close by) when they have attained the adult’s black-and-white feathers at the age of three. However, current research is finding that many loons do not acquire a nesting territory until they are five years old, so most end up swimming around our lakes, waiting for an open territory.
Contact LoonWatch for more information. LoonWatch is a program of the Sigurd Olson Environmental Institute, Northland College, Ashland, WI 54806;
(715) 682-1220; [email protected]; www.northland.edu/loonwatch.