Plants and Animals

Vertigo tridentata Honey vertigo

Key Characteristics

The ovate to tapering oblong shell of the honey vertigo is approximately .08 inches in height with five smooth whorls of a glossy amber color and relatively few lamellae and folds. The body is short and tapering toward the back, with long and pointed eye peduncles and no tentacles.

Status and Rank

US Status:
State Status: SC - Special Concern (rare or uncertain; not legally protected)
Global Rank: G5 - Secure
State Rank: SNR - Not ranked

Occurrences

CountyNumber of OccurrencesYear Last Observed
Kalamazoo1
Mackinac12013

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

The honey vertigo inhabits calcareous grasslands, wooded outcrops and mesic forests (Nekola 2009).

Specific Habitat Needs

needed in: AlvarBedrock gladeLimestone bedrock gladeMesic northern forestMesic southern forest.

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

As the majority of land snails are incapable of widely dispersing to search for new suitable habitat, habitat loss, fragmentation and degradation are considered their greatest threats (Kay 1995). Many vulnerable species of this group depend on moist microhabitats with a rich layer of organic litter and healthy, uncompacted soil (Nekola 2003). Increased edge area, forest canopy reductions, and the loss of vegetative ground cover through intensive recreational use and heavy grazing (Suominen 1999) may unfavorably alter microhabitat characteristics (Applegarth 1999, Gotmark et al. 2008, Walden 1995). Identification and conservation of important habitat areas for land snail species is a necessary first step toward management. Wild and prescribed fire has a significant negative effect on land snail abundance and diversity (Applegarth 1999, Nekola 2002). As large downed logs may provide important refuges during fire and drought, snags should be retained (Applegarth 1999). Alternatives to prescribed fire should be explored where vulnerable snails are present. Snails rapidly bioaccumulate chemical pollutants and heavy metals (Berger and Dallinger 1993, Regoli et al. 2006), high exposure to which has been found to prevent reproduction (Notten et al. 2006). Herbicides and insecticides should be applied with caution and affected populations monitored to evaluate impacts. Unchecked recreational rock climbing has a negative effect on the vegetation of limestone outcrops, which provides some of the most important habitat for a wide variety of terrestrial snails, including the honey vertigo (McMillan et al. 2003).    

Active Period

Breeding from first week of May to fourth week of June

Survey Methods

As visual detection of this species is difficult, specimens are collected by litter sampling in suitable habitat. Samples are thoroughly heat-dried, soaked in water for a number of hours to separate the various components, and finally passed through a series of sieves. The shells are then able to be hand-picked from the remaining sample material (Nekola 2003).

Litter sampling

Survey Period: From first week of April to first week of October

Time of Day: Daytime

References

Survey References

  • Nekola, J.C. 2003. Large-scale terrestrial gastropod community composition patterns in the Great Lakes region of North America. Diversity and Distributions 9:55-71.

Technical References

  • Applegarth, J.S. 1999. Management recommendations for terrestrial mollusk species, Megophix hemphilli, the Oregon Megomphix. Version 2.0. 39pp.
  • Baker, F.C. 1939. Fieldbook of Illinois Land Snails. Illinois Natural History Survey Manual 2, Urbana, Illinois. 166pp.
  • Berger, B. and R. Dallinger. 1993. Terrestrial snails as quantitative indicators of environmental metal pollution. Environmental Monitoring and Assessment 25(1):65-84.
  • Gotmark, F., T. Von Proschwitz, and N. Franc. 2008. Are small sedentary species affected by habitat fragmentation? Local vs. landscape factors predicting species richness and composition of land molluscs in Swedish conservation forests. Journal of Biogeography 35: 1062-76.
  • Kay, E.A. 1995. Hug a slug, save a snail: A status report on molluscan diversity and a framework for conservation action. Pp. 53-79. In: E.A. Kay (ed). 1995. The Conservation Biology of Molluscs. IUCN, Gland, Switzerland.
  • McMillan, M.A., J.C. Nekola, and D.W. Larson. 2003. Effects of Rock Climbing on the Land Snail Community of the Niagara Escarpment in Southern Ontario, Canada. Conservation Biology 17(2):616-21.
  • Nekola, J.C. 2002. Effects of fire management on the richness and abundance of central North American grassland land snail faunas. Animal Biodiversity and Conservation 25(2):53-66.
  • Nekola, J.C. 2003. Large-scale terrestrial gastropod community composition patterns in the Great Lakes region of North America. Diversity and Distributions 9:55-71.
  • Nekola, J.C. 2009. Conservation Prioritization of the Ontario and Quebec Land Snail Faunas. Final Report Submitted to: Committee on the Status of Endangered Wildlife in Canada (COSEWIC). 120 pp.
  • Notten, M.J.M., A.J.P. Oosthoek, J. Rozema, and R. Aerts. 2006. Heavy metal pollution affects consumption and reproduction of the landsnail Cepaea nemoralis fed on naturally polluted Urtica dioica leaves. Ecotoxicology 15(3):295-304.
  • Regoli, F., S. Gorbi, D. Fattorini, S. Tedesco, A. Notti, N. Machella, R. Bocchetti, M. Benedetti, and F. Piva. 2006. Use of the Land Snail Helix aspersa as Sentinel Organism for Monitoring Ecotoxicologic Effects of Urban Pollution: An Integrated Approach. Environmental Health Perspectives 114(1):63-69.
  • Suominen, O. 1999. Impact of cervid browsing and grazing on the terrestrial gastropod fauna in the boreal forests of Fennoscandia. Ecography 22:651-58.
  • Walden, H.W. 1995. Endangered species of land molluscs in Sweden and Madeira. In: The IUCN Species Survivial Commission, The Conservation Biology of Molluscs:19-24 (E. Alison Kay, Ed.) International Union for Conservation of Nature and Natural Resources, Gland, Switzerland.