White prairie gentian evaluation
This document describes the Committee on the Status of Species at Risk in °ÄÃÅÓÀÀû’s evaluation of the white prairie gentian. This evaluation determines whether the species will receive protection under the Endangered Species Act.
Committee on the Status of Species at Risk in °ÄÃÅÓÀÀû (COSSARO)
Assessed by COSSARO as Endangered
February 2011
Final
Part 1: COSSARO Candidate Species at Risk evaluation form
White Prairie Gentian (Gentiana alba)
Current designations:
GRANK – G4
NRANK Canada – N1
COSEWIC – Endangered (November 2010)
SARA – Endangered (Schedule 1) General Status Canada – At Risk (2005) ESA 2007 – EN
SRANK – S1
General Status °ÄÃÅÓÀÀû – At Risk (2005)
Distribution and status outside °ÄÃÅÓÀÀû:
Native to eastern North America, occurs from Minnesota and Wisconsin to Pennsylvania in the north of its range to Nebraska and Oklahoma to West Virginia in the south. In Canada, White Prairie Gentian occurs only in °ÄÃÅÓÀÀû.
Eligibility criteria
Native status
Yes. There is no evidence to suggest that this is not a native species in °ÄÃÅÓÀÀû.
Taxonomic distinctness
Yes. There has been considerable confusion over the name of this species, but no dispute over its status as a taxonomic entity.
Designatable units
There is only one DU for this species in °ÄÃÅÓÀÀû. The only records are from southern °ÄÃÅÓÀÀû in the Great Lakes Plains Ecological Area.
Priority-setting criteria
Recent arrival
No. Although the existing populations for this species were not discovered until 1984, historic records date back to 1840 and 1891.
Non-resident
No. This species is native of °ÄÃÅÓÀÀû.
Primary criteria (rarity and declines)
1. Global rank
Not in any category. G4
2. Global decline
Not in any category. There are no data documenting a global decline, but ongoing conversion of land-use, habitat fragmentation and forest management practices threaten the species through much of its range (Southern Appalachian Species Viability Project, 2002).
3. Northeastern North America ranks
TH. The species is ranked S1, S2, SH of SX in 64% of 9 NE American jurisdictions in which it is ranked. It is ranked S3 in Iowa, Wisconsin and Minnesota.
4. Northeastern North America decline
Not in any category. There are no data to demonstrate a decline in NE North America.
5. °ÄÃÅÓÀÀû occurrences
EN. There is only one extant occurrence of this species in °ÄÃÅÓÀÀû. The single population is divided into three stands. One stand consists of a single individual that has not flowered for several years, and another stand contains 1-3 plants that do not flower each year.
6. °ÄÃÅÓÀÀû decline
Not in any category. The number of flowering stems appears to have decreased to 99 from a high of 143 in 2003 (30%), but not all plants flower every year, and the number of flowering stems per plant may vary from year to year. There is insufficient evidence of a decline. There were 42 plants in 2008 and in 1997 and about 30 plants in 1986 (COSEWIC, 2010).
7. °ÄÃÅÓÀÀû’s conservation responsibility
Not in any category. °ÄÃÅÓÀÀû has <1% of the global range and <1% of the population.
Secondary criteria (threats and vulnerability)
1. Population sustainability
Not in any category. There are no data on which to base a PVA.
2. Lack of regulatory protection for exploited wild populations
Not in any category. This species is protected under Schedule 1 of the federal Species at Risk Act which was passed in 2002 and applies to populations on Federal Land, including Walpole Island First Nation (WIFN). In °ÄÃÅÓÀÀû it is protected under the provincial Endangered Species Act, 2007, which provides protection for the species since June 2008, but the habitat will not be legally protected until June 2013.
3. Direct threats
EN. Two of the stands consist of a 1-3 plants that could be subject to stochastic events. One of these is threatened by encroachment of trees due to lack of fires. It is also in a disturbed area adjacent to a recently expanded cemetery. Regular fires are required to maintain the savannah habitat for all three stands. House building is also a threat because of the critical housing shortage on WIFN. Lack of planning was identified as a threat to species at risk in the Draft Walpole Island Ecosystem Recovery Strategy (Bowles, 2005). The main stand has an ATV track running through it and some plants get crushed each year.
Hybridization with the more common Gentiana andrewsii is occurring, but the extent of contamination is unknown. Waldron (1991) suggested that seed herbivory is a threat but the extent of its effects is not known.
4. Specialized life history or habitat-use characteristics
EN. In Canada this species only grows in tallgrass savannah, a habitat listed as S1, critically imperiled. The habitat requires a regular fire regime to prevent encroachment by trees and shrubs.
Cossaro criteria met (primary/secondary)
Endangered – [1/2]
Threatened – [1/0]
Special concern – [0/0]
Recommended Status: Endangered.
Summary
White Prairie Gentian (Gentiana alba) is Endangered in °ÄÃÅÓÀÀû. This sprawling perennial can be up to 1 m tall. Its white, spindle-shaped flowers are about 3.5 cm long and cluster near the tip of the stem. In °ÄÃÅÓÀÀû there is a single extant population in remnant oak savannahs on Walpole Island. There are < 50 individuals in the population, and they are at risk from encroachment by woody species that causes shading. Trampling and genetic contamination through hybridization are additional threats. The single population, specialized and scarce habitat, small number of individuals and ongoing threats support a designation as Endangered.
Information sources
Bowles, J.M.. 2005. Draft Walpole Island Ecosystem Recovery Strategy. Prepared for Walpole Island Heritage Centre and Environment Canada. 50 pp.
COSEWIC. 2000. COSEWIC assessment and status report on the White Prairie Gentian Gentiana alba in Canada. Committee on the Status of Endangered Wildlife in Canada, Ottawa. vi + 14 pp.
COSEWIC. 2010. Update COSEWIC status report on White Prairie Gentian (Gentiana alba) in Canada. Committee on the Status of Endangered Wildlife in Canada, 2-month Interim Status Report. Ottawa. viii + 16 pp.
MNR, 2011. Ministry of Natural Resources. Species at Risk Website.. Accessed January 2011.
NatureServe 2011. . Accessed January 2011.
Southern Appalachian Species Viability Project. 2002. A partnership between the U.S. Forest Service-Region 8, Natural Heritage Programs in the Southeast, NatureServe, and independent scientists to develop and review data on 1300+ regionally and locally rare species in the Southern Appalachian and Alabama region. Database (Access 97) provided to the U.S. Forest Service by NatureServe, Durham, North Carolina.
, 2011. Accessed January 2011.
Waldron, G.E. 1991. COSEWIC status report on the White Prairie Gentian Gentiana alba in Canada. Committee on the Status of Endangered Wildlife in Canada. 29 pp.
Wild Species, 2005. General Status Search Tool. [http://www.wildspecies.ca/wildspecies2005/search.cfm?lang=e&sec=9]. [link inactive] Accessed January 2011.
Appendix 1: Northeastern North America rank, status and decline
| Province/State | North America rank, status and decline |
|---|---|
| CT | Not present |
| DE | Not present |
| IL | SNR |
| IN | S2 |
| IA | S3 |
| KY | S1 |
| LB | Not present |
| MA | Not present |
| MB | Not present |
| MD | SNR |
| ME | Not present |
| MI | S3 |
| MN | SNR |
| NB | Not present |
| NF | Not present |
| NH | Not present |
| NJ | Not present |
| NS | Not present |
| NY | Not present |
| OH | S2 |
| ON | S1 |
| PA | SH |
| PE | Not present |
| QC | Not present |
| RI | Not present |
| VA | Not present |
| VT | Not present |
| WI | S3 |
| WV | S1 |
Occurs as a native species in 12 of 29 northeastern jurisdictions SRANK or equivalent information available for 9 of 12 jurisdictions = 75% S1, S2, SH, or SX in 6 of 9 = 64%
Part 2: °ÄÃÅÓÀÀû evaluation using COSEWIC criteria
Regional (°ÄÃÅÓÀÀû) COSEWIC criteria assessment
Criterion A – Decline in total number of mature individuals
No. (N/A). There is no evidence to support a reduction in the total number of individuals. Population is small, but stable.
Criterion B – Small distribution range and decline or fluctuation
Yes (EN B1 a b(iii) + B2 a b(iii)). The EO and IAO are both much smaller than threshold values. There are <5 locations and the there is continuing decline in the area and quality of habitat.
Criterion C – Small and declining number of mature individuals
No. (N/A). The population is small, <2,500, but appears to be stable.
Criterion D – Very small or restricted total population
Yes. (EN D1). The population size is <250 individuals.
Criterion E – Quantitative analysis
No. (N/A). No data available.
Rescue effect
No. Rescue is very unlikely. Available habitat is restricted and the species is very rare in the adjacent states (Michigan – S1, Ohio – S2, Pennsylvania – SH)