COSEWIC Assessment and Update Status Report on the Northern Cricket Frog Acris crepitans in Canada ENDANGERED 2001 COSEWIC status reports are working documents used in assigning the status of wildlife species suspected of being at risk. This report may be cited as follows: Please note: Persons wishing to cite data in the report should refer to the report (and cite the author(s)); persons wishing to cite the COSEWIC status will refer to the assessment (and cite COSEWIC). A production note will be provided if additional information on the status report history is required. COSEWIC. 2001. 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. v + 14 pp. (www.sararegistry.gc.ca/status/status_e.cfm). Britton, D. 2001. COSEWIC update status report on the Northern Cricket Frog Acris crepitans in Canada in 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. 1-14 pp. Previous report(s): Oldham, M.J. and C.A. Campbell. 1990. COSEWIC status report on the Northern Cricket Frog Acris crepitans in Canada. Committee on the Status of Endangered Wildlife in Canada. Ottawa. 33 pp. Production note: Northern Cricket Frog Acris crepitans was, for several years, designated by COSEWIC as Blanchard’s Cricket Frog Acris crepitans blanchardi. For additional copies contact: COSEWIC Secretariat c/o Canadian Wildlife Service Environment Canada Ottawa, ON K1A 0H3 Tel.: (819) 997-4991 / (819) 953-3215 Fax: (819) 994-3684 E-mail: COSEWIC/[email protected] http://www.cosewic.gc.ca Également disponible en français sous le titre Ếvaluation et Rapport de situation du COSEPAC sur la rainette grillon (Acris crepitans) au Canada – Mise à jour. Cover illustration/photo: Northern Cricket Frog — ©Suzanne L. Collins. ©Her Majesty the Queen in Right of Canada, 2011. Catalogue No. CW-14/189-2002E-IN ISBN 0-662-32619-9 Recycled paper COSEWIC Assessment Summary Assessment Summary – May 2001 Common name Northern Cricket Frog Scientific name Acris crepitans Status Endangered Reason for designation Due to continuing declines in the extent of the species’ occurrence, area of occupancy, extent of habitat and number of individuals, any remaining individuals of this frog species would exist in a single small population on Pelee Island. Occurrence Ontario Status history Designated Endangered in April 1990. Status re-examined and confirmed in May 2001. iii COSEWIC Executive Summary Northern Cricket Frog Acris creptians Although widespread in the United States, the Northern Cricket Frog (Acris crepitans) is known in Canada exclusively from the extreme southwest of Ontario where its existence has been confirmed only at Point Pelee and Pelee Island. The Point Pelee population, known from a handful of historical records, was never well known and is believed to be extirpated. On Pelee Island, A. crepitans was documented from as many as twenty sites during the early 1970’s. However, during that decade, these underwent a precipitous decline, until, after 1977, A. crepitans was known to persist in Canada at only a single site on Pelee Island: Fish Point Provincial Nature Reserve, located at the southern tip of the island. Damage to habitat, including the drainage of marshes, the dredging of drainage canals that were used as breeding sites and the scouring of coastal marshes during severe storms are believed to be key reasons for the decline of A. crepitans on Pelee Island. Other factors that may have contributed to the species’ decline include predation by birds, reptiles, bullfrogs and fish, and use of pesticides and herbicides. Habitat destruction has also been identified as the major cause of recent declines of the species in the American Midwest. Over the last two decades, observations and auditions of A. crepitans have been reported sporadically from Fish Point, including one as recently as 1997. Unfortunately, none of these more recent reports are supported by photographs or audio recordings of calling frogs. The lack of confirmed reports, coupled with the relatively small size of Fish Point and the short lifespan of individual frogs has led a number of authors to suggest that A. crepitans has been extirpated from Canada. Nevertheless, it may be premature to consider the species extirpated and thus it is recommended that the status of A. crepitans in Canada remain as endangered. iv COSEWIC MANDATE The Committee on the Status of Endangered Wildlife in Canada (COSEWIC) determines the national status of wild species, subspecies, varieties, and nationally significant populations that are considered to be at risk in Canada. Designations are made on all native species for the following taxonomic groups: mammals, birds, reptiles, amphibians, fish, lepidopterans, molluscs, vascular plants, lichens, and mosses. COSEWIC MEMBERSHIP COSEWIC comprises representatives from each provincial and territorial government wildlife agency, four federal agencies (Canadian Wildlife Service, Parks Canada Agency, Department of Fisheries and Oceans, and the Federal Biosystematic Partnership), three nonjurisdictional members and the co-chairs of the species specialist groups. The committee meets to consider status reports on candidate species. DEFINITIONS Species Any indigenous species, subspecies, variety, or geographically defined population of wild fauna and flora. Extinct (X) A species that no longer exists. Extirpated (XT) A species no longer existing in the wild in Canada, but occurring elsewhere. Endangered (E) A species facing imminent extirpation or extinction. Threatened (T) A species likely to become endangered if limiting factors are not reversed. Special Concern (SC)* A species of special concern because of characteristics that make it particularly sensitive to human activities or natural events. Not at Risk (NAR)** A species that has been evaluated and found to be not at risk. Data Deficient (DD)*** A species for which there is insufficient scientific information to support status designation. * Formerly described as “Vulnerable” from 1990 to 1999, or “Rare” prior to 1990. ** Formerly described as “Not In Any Category”, or “No Designation Required.” *** Formerly described as “Indeterminate” from 1994 to 1999 or “ISIBD” (insufficient scientific information on which to base a designation) prior to 1994. 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, COSEWIC designated 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. The Canadian Wildlife Service, Environment Canada, provides full administrative and financial support to the COSEWIC Secretariat. v Update COSEWIC Status Report on the Northern Cricket Frog Acris crepitans in Canada 2001 TABLE OF CONTENTS INTRODUCTION............................................................................................................. 3 DISTRIBUTION............................................................................................................... 3 PROTECTION................................................................................................................. 6 POPULATION SIZE AND TREND .................................................................................. 7 HABITAT AND GENERAL BIOLOGY ............................................................................. 8 LIMITING FACTORS....................................................................................................... 9 SPECIAL SIGNIFICANCE OF THE SPECIES .............................................................. 10 EVALUATION ............................................................................................................... 11 ACKNOWLEDGEMENTS ............................................................................................. 12 LITERATURE CITED .................................................................................................... 12 THE AUTHOR............................................................................................................... 14 List of Figures Figure 1. Distribution of the Northern Cricket Frog (Acris crepitans) in Ontario............... 4 Figure 2. Distribution of the Northern Cricket Frog (Acris crepitans) on Pelee Island. .... 5 List of Tables Table 1. Mainland Ontario records for A. crepitans (Fig. 1). Question marks indicate unconfirmed reports. From Oldham and Campbell (1990). ............................. 4 Table 2. Pelee Island records for A. crepitans (Fig. 2). Question marks indicate unconfirmed records. Modified from Oldham and Campbell (1990). ............... 6 INTRODUCTION The Northern Cricket Frog (Acris crepitans) is a small treefrog of the family Hylidae widespread throughout eastern North America. In Canada, its occurrence has only been confirmed at two localities: Point Pelee and Pelee Island in extreme southwestern Ontario. DISTRIBUTION Acris crepitans is distributed widely in the eastern and central United States. It ranges from Texas to southeastern South Dakota in the western part of its range, and from the Gulf states to southeastern New York in the east. It is absent from much of the Appalachian
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