Plants and Animals

Trimerotropis huroniana Lake Huron locust

species photo
David Cuthrell
species photo
Doug Pearsall

Key Characteristics

The Lake Huron locust is a small ash-gray grasshopper with darker brown and white markings and wings with a prominent dark band. The pronutum (saddle-like structure behind the head) is cut by two narrow grooves (sulci), and a broad (not narrow) black band covers half the inner surface of the hind femora near the body.

Status and Rank

US Status: No Status/Not Listed
State Status: T - Threatened (legally protected)
Global Rank: G4 - Apparently secure
State Rank: S2S3 - Rank is uncertain, ranging from imperiled to vulnerable

Occurrences

CountyNumber of OccurrencesYear Last Observed
Alcona 4 2010
Alger 2 1997
Alpena 2 1996
Antrim 2 2009
Benzie 4 2009
Charlevoix 16 2015
Cheboygan 3 1996
Chippewa 4 1997
Emmet 9 2011
Huron 1 1924
Iosco 2 1996
Leelanau 4 2009
Luce 4 1997
Mackinac 16 2006
Manistee 3 1996
Mason 2 1996
Presque Isle 4 1996
Schoolcraft 11 2006

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

This species occurs only in sparsely vegetated, high-quality Great Lakes sand dunes along northern Lake Michigan, northern Lake Huron, and eastern Lake Superior. Ideal habitat includes at least a mile of shoreline with two or more sets of dunes with blowouts. It primarily feeds on dune grass, beach grass, and wormwood, but will eat other forbs also, including the federally threatened pitcher's thistle (Cirsium pitcheri).

Specific Habitat Needs

Sandy substrate needed in: Open dunes.

Natural Community Types

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

Protection of remaining dune habitat is critical, especially from development and ORV use. Species does not survive well in weedy habitat or disturbed sites where dune dynamics are altered through complete removal of vegetation.

Active Period

Active from second week of July to second week of October

Survey Methods

The species is most active in late morning, after 9:30 or 10. Males crepitate in flight, making a cracking noise.

Visual, auditory, net

Survey Period: From second week of July to second week of October

Time of Day: Morning (after sunrise)

References

Survey References

  • Borror, D.J. and R.E. White. 1970. A Field Guide to the Insects of North America and Mexico. Houghton Mifflin Company, Boston. 404pp.
  • Martin, J.E.H. 1977. The Insects and Arachnids of Canada (Part 1): Collecting, preparing, and preserving insects, mites, and spiders. Publication 1643. Biosystematics Research Institute, Ottawa.

Technical References

  • Bland, R.G. 2003. The Orthoptera of Michigan: Biology, Keys, and Descriptions of Grasshoppers, Katydids, and Crickets. Michigan State University Extension, East Lansing. Extension Bulletin E-2815. 220pp.
  • Dunn, G.A. 1999. Insects of the Great Lakes Region. University of Michigan Press, Ann Arbor. 324pp.
  • Evers, D.C. 1994. Endangered and Threatened Wildlife of Michigan. The University of Michigan Press, Ann Arbor. 412pp.
  • Rabe, M.L. 1999. Special Animal Abstract for Trimerotropis huroniana (Lake Huron locust). Michigan Natural Features Inventory, Lansing, MI 3pp.