COSEWIC Status Appraisal Summary on the Small Whorled Pogonia Isotria medeoloides in Canada
COSEWIC status appraisal summaries are working documents used in assigning the status of wildlife species suspected of being at risk in Canada. This document may be cited as follows:
COSEWIC. 2011. COSEWIC status appraisal summary on the Small Whorled Pogonia Isotria medeoloides in Canada. Committee on the Status of Endangered Wildlife in Canada. Ottawa. xi pp.
(Species at Risk Status Reports)
For additional copies contact:
c/o Canadian Wildlife Service
Également disponible en français sous le titre Sommaire du statut de l’espèce du COSEPAC sur l’isotrie fausse-médéole (Isotria medeoloides) au Canada.
© Her Majesty the Queen in Right of Canada, 2011.
Catalogue No.: CW69-14/2-10-2011E-PDF
Status Appraisal Summary
Current COSEWIC Assessment:
Recommendation: Update to the status report NOT required (wildlife species’ status category remains unchanged)
Evidence (indicate as applicable):
Michael Oldham, Botanist/Herpetologist, Natural Heritage Information Centre, Ontario Ministry of Natural Resources, Peterborough, Ontario.
Ron Gould, Species at Risk Biologist, Ontario Ministry of Natural Resources, Chatham, Ontario.
Susi von Oettingen, Endangered Species Biologist, US Fish and Wildlife Service, Concord, New Hampshire.
Tony Difazio, Resource Planning Coordinator, Catfish Creek Conservation Authority, Aylmer, Ontario.
Sources of Information
Arnolds, E., 1991. Decline of ectomycorrhizal fungi in Europe. Agriculture, ecosystems and environment, 35: 209–244.
Bohlen, P.J., S. Scheu, C.M. Hale, M.A. McLean, S. Migge, P.M. Groffman and D. Parkinson. 2004. Non-native invasive earthworms as agents of change in northern temperate forests. Frontiers in Ecology and the Environment 2(8): 427 435.
Brumback, W.E.; Fyler, C.W. 1988. Monitoring of Isotria medeoloides in New Hampshire. Wild Flower Notes. 3: 32-40.
Brumback, W., C. Fyler, and J. Korecki. 2008. Monitoring and Habitat Management of Isotria medeoloides at E. Alton, New Hampshire: 2007. In completion of Cooperative Agreement No. 53410-6-0623 U.S. Fish and Wildlife Service. 14 pp., New England Field Office, Concord, New Hampshire. 5 pp.
Correll, D.S. 1950. Native orchids of North America north of Mexico. Stanford University Press, Stanford, California. 399 pp.
COSEWIC2011. COSEWIC's Assessment Process and Criteria (PDF; 112 KB). [Accessed Feb. 2011]
Hale, C.M., L.E. Frelich, and P.B. Reich. 2005. Exotic European earthworm invasion dynamics in northern hardwood forests of Minnesota, USA. Ecological Applications 15(3): 848-860.
Hendrix, P.F., and P.T. Bohlen. 2002. Exotic Earthworm Invasions in North America: Ecological and Policy Implications. BioScience 52(9): 801-811.
Holsinger et al. 1996. “Reproductive patterns and the cost of reproduction in an endangered orchid Isotria medeoloides: A ten year retrospective,” Ecological Society of America, Providence, Rhode Island, 8-11-96 to 8-14-96 (with P. Vitt, S.C. Gawler, A. Dibble, T. Vining, W.A. Wright, and C.S. Campbell; presented by P. Vitt). Cited in W. Brumback, C. Fyler, and J. Korecki. 2008. Monitoring and Habitat Management of Isotria medeoloides at E. Alton, New Hampshire: 2007. In completion of Cooperative Agreement No. 53410-6-0623 U.S. Fish and Wildlife Service. 14 pp.
McConnell, A. 2007. Recovery Strategy for the Small Whorled Pogonia (Isotria medeoloides) in Canada. 13 pp.
McCormick, M.K., D.F. Whigham, and J. O’Neill. 2004. Mycorrhizal diversity in photosynthetic terrestrial orchids. New Phytologist: 163: 425-438.
Endangered Species Act, 2007. Website accessed April 9 2010.
Mehrhoff, L.A. 1989b. The dynamics of declining populations of an endangered orchid, Isotria medeoloides. Ecology 70(3): 783-786.
Shefferson, R.P., M. Weiss, T. Kull and D.L. Taylor. 2005. High specificity generally characterizes mycorrhizal association in rare lady’s slipper orchids, genus Cypripedium. Molecular Ecology 14, 613–626.
U.S. Fish and Wildlife Service, 2008. Small Whorled Pogonia (Isotria medeoloides) 5-year Review: Summary and Evaluation. New England Field Office, Concord New Hampshire. 25 pp.
Wardle, D. 2002. Communities and ecosystems: linking the above-ground and belowground components. Princeton University Press, Princeton, New Jersey.
White, D.J. 1998. Update COSEWICstatus report on the Small Whorled Pogonia Isotria medeoloides in Canada. Committee on the Status of Endangered Wildlife in Canada. Ottawa. 1-6 pp.
Author of Status Appraisal Summary
Samuel R. Brinker
Range of occurrence in Canada: Ontario
(likely > 10 years)
|Is there an observed continuing decline in number of mature individuals?|
(No Canadian reports since 1998)
|Estimated percent of continuing decline in total number of mature individuals within 5 years or 2 generations||n/a|
|Observed percent reduction or increase in total number of mature individuals over the last 10 years, or 3 generations.||100%|
|Projected percent increase in total number of mature individuals over the next 10 years.||unknown|
|Inferred percent increase in total number of mature individuals over any 10 years, or 3 generations period, over a time period including both the past and the future.||unknown|
|Are the causes of the decline clearly reversible and understood and ceased?||unknown|
|Are there extreme fluctuations in number of mature individuals?|
(No mature individuals are known)
Extent and Occupancy Information
|Estimated extent of occurrence||0 km2|
|Index of area of occupancy (IAO)||0 km2 (2x2 km)|
|Is the total population severely fragmented?|
(No extant populations known)
|Number of "locations*"||0|
|Is there an observed continuing decline in extent of occurrence?||No|
|Is there an observed and projected continuing decline in index of area of occupancy?||No|
|Is there an observed continuing decline in number of populations? (historical decline)||No|
|Is there an observed continuing decline in number of locations?||No|
|Is there an observed continuing decline in quality of habitat?|
(exotic earthworms continue to degrade the habitat)
|Are there extreme fluctuations in number of populations?||No|
|Are there extreme fluctuations in number of locations*?||No|
|Are there extreme fluctuations in extent of occurrence?||No|
|Are there extreme fluctuations in index of area of occupancy?||No|
* See definition of location.
Number of Mature Individuals (in each population)
|Population||Number of Mature Individuals|
Threats (actual or imminent, to populations or habitats)
Rescue Effect (immigration from outside Canada)
|Globally Imperilled (G2);|
Listed Threatened in the US and Imperilled (N2);
District of Columbia (SX),
New Hampshire (S2),
New Jersey (S1),
New York (SH),
North Carolina (S2),
Rhode Island (S1),
South Carolina (S2),
West Virginia (S1)
|Is immigration known or possible?||Unlikely|
|Would immigrants be adapted to survive in Canada?||unknown|
|Is there sufficient habitat for immigrants in Canada?||no|
|Is rescue from outside populations likely?|
The only Small Whorled Pogonia population in Canada (if extant) remains geographically isolated with little chance of immigration from adjacent areas to the south in New York or Michigan. The Canadian population is not contiguous with any U.S. populations and it is unlikely that propagules from elsewhere would become established in Canada. Small Whorled Pogonia is rare throughout its northeastern North American range and populations tend to be small.
Status and Reasons for Designation
A2a; B1ab(iii)+2ab(iii); D1
|Reasons for designation:|
This small orchid, previously known only from a single swamp in Ontario, requires mixed damp woods. It was assessed as Endangered in 2000. Its habitat continues to decline in quality due to trampling and exotic earthworms. It was last seen in 1998, though its potential for dormancy means it may still be extant.
Applicability of Criteria
The Committee on the Status of Endangered Wildlife in Canada (COSEWIC) was created in 1977 as a result of a recommendation at the Federal–Provincial Wildlife Conference held in 1976. It arose from the need for a single, official, scientifically sound, national listing of wildlife species at risk. In 1978, COSEWICdesignated its first species and produced its first list of Canadian species at risk. Species designated at meetings of the full committee are added to the list. On June 5, 2003, the Species at Risk Act (SARA) was proclaimed. SARAestablishes COSEWICas an advisory body ensuring that species will continue to be assessed under a rigorous and independent scientific process.
The Committee on the Status of Endangered Wildlife in Canada (COSEWIC) assesses the national status of wild species, subspecies, varieties, or other designatable units that are considered to be at risk in Canada. Designations are made on native species for the following taxonomic groups: mammals, birds, reptiles, amphibians, fishes, arthropods, molluscs, vascular plants, mosses, and lichens.
COSEWICcomprises members from each provincial and territorial government wildlife agency, four federal entities (Canadian Wildlife Service, Parks Canada Agency, Department of Fisheries and Oceans, and the Federal Biodiversity Information Partnership, chaired by the Canadian Museum of Nature), three non–government science members and the co–chairs of the species specialist subcommittees and the Aboriginal Traditional Knowledge subcommittee. The Committee meets to consider status reports on candidate species.
- Wildlife Species
- A species, subspecies, variety, or geographically or genetically distinct population of animal, plant or other organism, other than a bacterium or virus, that is wild by nature and is either native to Canada or has extended its range into Canada without human intervention and has been present in Canada for at least 50 years.
- Extinct (X)
- A wildlife species that no longer exists.
- Extirpated (XT)
- A wildlife species no longer existing in the wild in Canada, but occurring elsewhere.
- Endangered (E)
- A wildlife species facing imminent extirpation or extinction.
- Threatened (T)
- A wildlife species likely to become endangered if limiting factors are not reversed.
- Special Concern (SC)*
- A wildlife species that may become a threatened or an endangered species because of a combination of biological characteristics and identified threats.
- Not at Risk (NAR) **
- A wildlife species that has been evaluated and found to be not at risk of extinction given the current circumstances.
- Data Deficient (DD) ***
- A category that applies when the available information is insufficient (a) to resolve a species’ eligibility for assessment or (b) to permit an assessment of the species’ risk of extinction.
- Date Modified: