COSSARO Candidate Species at Risk Evaluation. for. Blanchard s Cricket Frog (Acris blanchardi)

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1 COSSARO Candidate Species at Risk Evaluation for Blanchard s Cricket Frog (Acris blanchardi) Committee on the Status of Species at Risk in Ontario (COSSARO) Assessed by COSSARO as EXTIRPATED June 2011 Final

2 Current Designations: PART 1 CURRENT STATUS AND DISTRIBUTION GRANK G5 (Assessed 19/05/2009) (NatureServe 2011, accessed 24/05/2011). NRANK Canada NH (NatureServe 2011, accessed 24/05/2011) COSEWIC Endangered (COSEWIC 2011) SARA Endangered (Schedule 1) (Environment Canada 2011a) ESA 2007 Endangered (Ministry of Natural Resources 2011) SRANK Ontario SX (NHIC, accessed 24/05/2011) (Note: Srank recently changed from SH to SX (extirpated), though this is not yet reflected on the NHIC or NatureServe web pages) (M Oldham pers. comm. May 26, 2011) Distribution in Ontario: This species was found on several sites on Pelee Island and also on Point Pelee. Other records from Ontario are unconfirmed. It has not been confirmed anywhere in Ontario since the late 1970 s, but unconfirmed records occurred into the 1990 s (COSEWIC 2001, Environment Canada 2011b, Oldham 2011). It is likely extirpated from Ontario given its short-lived life history, lack of recent records, and loss of habitat. Distribution and Status Outside Ontario: Acris blanchardi is found from Minnesota and Wisconsin eastward through Illinois, Indiana, Michgan and Ohio south to Kentucky and West Virginia. 1

3 PART 2 ELIGIBILITY FOR ONTARIO STATUS ASSESSMENT 2.1 APPLICATION OF ELIGIBILITY CRITERIA Taxonomic Distinctness Yes. The taxonomic status has been confirmed recently in several studies (COSEWIC 2011). The species was previously known as Acris crepitans blanchardi (Brodribb and Oldham 2001). Designatable Units There is only one Ontario designatable unit because there is no evidence of population structure and all populations were in a restricted area of extreme southwestern Ontario.. Native Status Yes. The species has been recorded in Ontario for over a century (COSEWIC 2011). Presence/Absence Extirpated. Blanchard s Cricket Frog has not been confirmed in Canada in more than 30 years (Environment Canada 2011b, COSEWIC 2011, Oldham 2011). This species is relatively easy to detect because it has a loud distinctive mating call at a predictable time of year and in the past few decades has been confined in Ontario to limited habitat on Pelee Island and Point Pelee. Despite prolonged targeted searches over decades, it has not been confirmed since the 1970 s. It is quite unlikely to have persisted since then at very low numbers because it has a short longevity and generation time (1-2 years) and would have a high probability of being extirpated by stochastic factors. It would not be able to recolonize from other areas over past 20+ years because there was only one location recently occupied on Pelee Island before it disappeared from Ontario altogether. The evidence indicating extirpation is summarized in COSEWIC (2011) and Oldham (2011). 2.2 ELIGIBILITY RESULTS 1. The putative taxon is valid. Yes 2. The taxon is native to Ontario. Yes 3. The taxon is extirpated from Ontario or extinct? Yes (extirpated) 2

4 PART 5 ONTARIO STATUS DETERMINATION Blanchard s Cricket Frog is classified as Extirpated in Ontario. Acris blanchardi is a small frog found from Minnesota and Wisconsin eastward through Illinois, Indiana, Michigan and Ohio south to Kentucky and West Virginia. Acris blanchardi is semi-aquatic and remains in, or close to, permanent water bodies. It is found in a wide variety of permanent water bodies including lakes, ponds, rivers and streams, especially in shallow water near shore where there is substantial vegetative cover. The species has declined throughout the northern portion of its range in the United States and shows no sign of recovery. This species was found in extreme southwest Ontario on Pelee Island and also on Point Pelee. Other records from Ontario are unconfirmed. There are 8 occurrences in the NHIC Element Occurrence database, all of which are either historic or extirpated. There are no confirmed observations of Blanchard's Cricket Frogs since the 1970 s despite considerable search effort, and the species is considered Extirpated from Ontario. 1.Literature Cited Information Sources Brodribb, K.E. and M.J. Oldham COSSARO candidate V, T, E species evaluation form for Blanchard s Cricket Frog (Acris crepitans blanchardi). Natural Heritage Information Centre, Ontario Ministry of Natural Resources, Peterborough ON. 13 pp. COSEWIC COSEWIC assessment and update status report on the northern cricket frog Acris crepitans in Canada. Committee on the Status of Endangered Wildlife in Canada. Ottawa. vi + 12 pp. COSEWIC COSEWIC Status Assessment Summary on the Blanchard s Cricket Frog Acris blanchardi in Canada. Committee on the Status of Endangered Wildlife in Canada (in press). Environment Canada 2011a. Species at Risk Public Registry, [ Accessed May 24, Environment Canada 2011b. Recovery Strategy for the Blanchard s Cricket Frog (Acris blanchardi) (Proposed). Species at Risk Act Recovery Strategy Series. Environment Canada, Ottawa. v + 21 pp. 3

5 Ministry of Natural Resources Species at Risk Website. [ Accessed May 24, NatureServe NatureServe Explorer, An Online Encyclopedia of Life. Acris blanchardi. Accessed May 24, NHIC Ontario Natural Heritage Information Centre Biodiversity Explorer. [ Accessed May 2011 Oldham, M.J Notes on the status of Blanchard s Cricket Frog (Acris blanchardi) in Ontario. Unpublished manuscript May pp. 2. Community and Aboriginal Traditional Knowledge Sources: None. No sources used for this report. 3. Acknowledgements None 4

6 APPENDIX 1 NORTHEASTERN NORTH AMERICA STATUS RANK AND DECLINE (NatureServe 2011) 1 CT Not Present DE Not Present IL S5 IN S4 IA S3? LB Not Present KY S5 MA Not Present MB Not Present MD Not Present ME Not Present MI S2S3 MN S1 NB Not Present NF Not Present NH Not Present NJ Not Present NS Not Present NY Not Present OH SNR ON SH PA Not Present PE Not Present QC Not Present RI Not Present VA Not Present VT Not Present WI S1 WV SH Occurs as a native species in 10 of 29 northeastern jurisdictions Srank or equivalent information available for 9 of 10 jurisdictions = (90%) S1, S2, SH, or SX in 4 of 9 = (44%) 1 Accessed May