Loon Study - Frequently Asked Questions

Which state has the most common loons?

 
In the continental U.S., surveys indicate Minnesota has the largest population of common loons with more 10,000 adults. Wisconsin has an estimated summer population of more than 3,000 adults. Additionally, states with breeding populations include Maine with approximately 4,100 adults, New York with an estimated range of 800-1,000, and New Hampshire with about 500 adult common loons.
 

How long each year do loons stay within their summer (breeding) range?

 
Loons return to northern forested lakes and rivers in the springtime, usually in April or early May. The breeding range includes Alaska and northern Canada south to Washington, Montana, Minnesota, Wisconsin and New Hampshire.

Breeding loons, like those radiomarked in this study, left breeding areas in late October to early November.

Loons spend the winter season along the Atlantic, Pacific, and Gulf coasts.
 

How far can loons fly in one day?

 
The telemetry data tracked the birds every 2-3 days during migration. In one documented case, a loon traveled 572 miles over a 3-day period.  In another case, a loon traveled consecutive distances of 388 and 419 miles, each during a 2-day period. These were likely single movements.
 

What is the farthest a loon has flown in one migration?

 
The distance between breeding and wintering grounds of the loons we monitored in Minnesota and Wisconsin ranged from 1,171 to 1,318 miles.
 

Do loons return to the same place to nest where they were born?

 
Biologists suspect that loons return to the same general area where they were born and try to work their way into a territory.  Loons do not reach breeding maturity until about their fourth summer.

Loon nests usually include two olive-brown, lightly spotted eggs. Nests are situated on a low mass of vegetation near water, often on an island.  Both adults incubate the eggs and share in care of the young.  
 

What is the difference in appearence between a male and female loon?

 
 Male and female loons are similar in appearance. Males are generally larger than their mates.

Seasonally, the adult common loon's plumage changes dramatically. The photo at right illustrates the common loon's winter markings; the photo above which shows an adult on its nest is indicative of the loon's summer (breeding) appearance.
 

Why does the baby loon ride on its mother's back?
How long does the baby loon ride on the mother's back?

Biologists suspect there are two primary reasons for back riding:

1. Back riding may serve to warm the chick.
2. Back riding may reduce predation.  During the first week after hatching a chick may spend more than half its time on adults. After a week there is a sharp drop in back-riding.
    

How long do loons live?

 
Loons are a long-lived bird. The oldest known common loon lived 18 years but their lifespan may be 25-30 years.
 

What do loons eat?

  
Common loons feed primarily on fish, other aquatic vertebrates, some invertebrates (including crayfish and aquatic insects), and occasionally on vegetation.
 

Why do loons make calling noises at night?

  
Loon calls are used to communicate among family members and to maintain territories during the breeding season.  Adult loons have four basic types of vocalizations; the yodel, hoot, wail, and tremelo.
 

How many different kinds of loons are there?

   
There are five recognized species of loons (family Gaviidae):

• Common Loon
   
• Arctic Loon
   
• Pacific Loon
   
• Red-throated Loon
   
• Yellow-billed Loon