Plants and Animals

Gavia immer Common loon

Key Characteristics

The Common loon is a large, heavy-bodied bird, averaging 32 inches (81.3 cm) in length, with a wingspan of about 5 feet (1.5 m). In breeding plumage, its head and dagger-like bill are dark, its breast white, and its back is a distinctive black and white checkerboard pattern.

Status and Rank

US Status:
State Status: T - Threatened (legally protected)
Global Rank: G5 - Secure
State Rank: S3 - Vulnerable

Occurrences

CountyNumber of OccurrencesYear Last Observed
Alcona112017
Alger352015
Allegan11988
Alpena52017
Antrim72017
Baraga212004
Barry72017
Benzie62017
Charlevoix92017
Cheboygan172017
Chippewa212015
Clare212017
Crawford82017
Delta51998
Dickinson182014
Emmet92015
Gladwin52013
Gogebic1142017
Grand Traverse252017
Houghton92018
Iosco82017
Iron682017
Isabella22017
Kalkaska192017
Keweenaw502011
Lake172017
Leelanau72003
Luce102013
Mackinac212006
Manistee42011
Marquette342017
Mason32017
Mecosta342017
Missaukee72017
Montcalm62006
Montmorency252017
Newaygo122015
Oakland11952
Oceana32012
Ogemaw252017
Ontonagon102017
Osceola102017
Oscoda82017
Otsego172017
Presque Isle172015
Roscommon92017
Schoolcraft442017
Wexford62017

Information is summarized from MNFI's database of rare species and community occurrences. Data may not reflect true distribution since much of the state has not been thoroughly surveyed.

Habitat

Typically, Common loons nest in sheltered islands on large, undeveloped inland lakes, although they may nest in lakes as small as 11 acres (4.5 hectares). Preferred nest sites are on small islands or bog mats, at the water’s edge. Nursery areas - quiet, shallow, sheltered coves - are important for rearing chicks.

Natural Community Types

  • Bog
  • Emergent marsh
  • Great lake, littoral, benthic
  • Great lake, littoral, midwater
  • Great lake, pelagic, benthic
  • Inland lake, pelagic, midwater

For each species, lists of natural communities were derived from review of the nearly 6,500 element occurrences in the MNFI database, in addition to herbarium label data for some taxa. In most cases, at least one specimen record exists for each listed natural community. For certain taxa, especially poorly collected or extirpated species of prairie and savanna habitats, natural community lists were derived from inferences from collection sites and habitat preferences in immediately adjacent states (particularly Indiana and Illinois). Natural communities are not listed for those species documented only from altered or ruderal habitats in Michigan, especially for taxa that occur in a variety of habitats outside of the state.

Natural communities are not listed in order of frequency of occurrence, but are rather derived from the full set of natural communities, organized by Ecological Group. In many cases, the general habitat descriptions should provide greater clarity and direction to the surveyor. In future versions of the Rare Species Explorer, we hope to incorporate natural community fidelity ranks for each taxon.

Management Recommendations

Loons are sensitive to human disturbance during the breeding season. Minimize maintenance activities within 1/4 mile of active nests during the breeding season. Nursery areas may be vulnerable also. Schedule construction, maintenance, or habitat management activities during the non-breeding season, from September through February. Application of herbicide to control aquatic vegetation should only be conducted outside the nesting season on lakes where loons nest, particularly on small lakes.

Active Period

Migration from second week of March to third week of May

Nesting from first week of May to fourth week of July

Migration from third week of October to third week of December

Survey Methods

Loons are easily surveyed by visually checking suitable habitat from shore or a boat throughout the day. Their presence may also be detected by their distinctive calls, which may be heard day or night.

Visual survey, listen for call

Survey Period: From first week of May to fourth week of July

Time of Day: Daytime

Time of Day: Night

References

Survey References

  • Bibby, C.J., N.D. Burgess, and D.A. Hill. 1992. Bird Census Techniques. Academic Press, New York.

Technical References

  • Evers, D.C. 1994. Endangered and Threatened Wildlife of Michigan. The University of Michigan Press, Ann Arbor. 412pp.
  • Sibley, D.A. 2000. The Sibley Guide to Birds. Knopf, Toronto. 544pp.