Species Profile

Eastern Banded Tigersnail

Scientific Name: Anguispira kochi kochi
Taxonomy Group: Molluscs
COSEWIC Range: Ontario
COSEWIC Assessment Date and Status Change: April 2017
COSEWIC Status: Endangered
COSEWIC Status Criteria: B1ab(i,ii,iii,iv,v)+2ab(i,ii,iii,iv,v)
COSEWIC Reason for Designation: This large terrestrial snail remains in small isolated habitat patches on Middle and Pelee islands, in Lake Erie. The loss of subpopulations on some smaller islands was probably due to habitat destruction from overabundant Double-crested Cormorants, which colonized the islands in the early 1980s, as well as human activities. Habitat loss and alteration on Pelee Island likely led to subpopulation declines and fragmentation. Climate change is the most serious threat.
COSEWIC History of Status Designation: Designated Endangered in April 2017.
SARA Status: Schedule 1, Endangered
Date of Listing (yyyy-mm-dd): 2021-08-12

Please note that this information is provided for general information purposes only. For the most up to date and accurate list of species listed under the Species at Risk Act, please see the Justice Laws Website.

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Quick Links: | Description | Habitat | Biology | Threats | Protection | National Recovery Program | Documents

Description

Banded Tigersnail is a large land snail (adult shell width 2.0 – 2.5 cm) with a globular, yellow to brown shell that has an opening in the centre when viewed from below and a light-coloured spiral band bordered by a darker band on either side. Variations include size, shell thickness, and colour of the shell, as well as the visibility of bands. Two subspecies are currently recognized: Anguispira kochi kochi on the Lake Erie islands in Ontario, and A. k. occidentalis in British Columbia. The Eastern and Western subspecies are part of the unique faunas of the Carolinian and northern Columbia Basin ecosystems, respectively, and have significance for biodiversity, research, and conservation. As part of the gastropod community in forest ecosystems, Banded Tigersnail plays a role in litter decomposition and nutrient cycling. [Updated by COSEWIC - Apr, 2017]

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Distribution and Population

The distribution of Banded Tigersnail is disjunct, consisting of an eastern and western North American component, and extends from southern Canada southward to Tennessee in the east and to Oregon in the west. In Canada, the Ontario and British Columbia populations are separated by over 2000 km with no connections through the US. In Ontario, Eastern Banded Tigersnail is currently known to occur on two islands in Lake Erie (Pelee and Middle islands). In British Columbia, Western Banded Tigersnail occurs in the southeastern part of the province with most records from the West Kootenay region. Eastern Banded Tigersnail could be confirmed only on Middle Island and Pelee Island during fieldwork in 2013 – 2015; historical habitat disturbance suggests a reduction in abundance in some sites on these islands. The species has apparently disappeared from Middle Sister Island, East Sister Island, and a property near Alvinston in Lambton County on the mainland. The persistence of the species on Hen and North Harbour islands is uncertain. The population is currently estimated at about 800,000 mature individuals. Recruitment was observed in most sites where the species was found alive. Rescue from outside Canada is not possible due to Lake Erie acting as a barrier. Nothing is known of densities and population trends of Western Banded Tigersnail, but it is probable that the species was historically more widespread and abundant than currently, particularly in larger river valleys. Most distribution records are recent (since the 1990s), and there are insufficient historical records to allow for comparisons. Threats to habitats continue from various sources and may result in declines in the future. Several records of the species exist from the vicinity of the Canada – US border, and where habitat is continuous, there is potential for rescue. However, due to poor dispersal ability of the snails and habitat fragmentation, rescue of British Columbia subpopulations from the US is of limited importance. [Updated by COSEWIC - Apr, 2017]

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Habitat

In Ontario, Chinquapin Oak-Nodding Onion treed alvar, dry-fresh Hackberry deciduous forest, dry-fresh Sugar Maple-White Ash deciduous forest, and dry Black Oak woodland are preferred habitats of the Banded Tigersnail. These habitats, encompassing approximately 98 ha in total, are characterized by the proximity of limestone bedrock to topsoil or a sandy soil with a substantial leaf litter layer. Pelee Island is largely developed for agriculture, and habitat loss is historical. Habitats continue to be affected by flooding and management measures such as invasive species control and prescribed burning, as well as erosion of the tip of Fish Point on Pelee Island. Middle Island has been uninhabited by humans since the 1980s, but habitats continue to be modified by storms and overabundant Double-Crested Cormorants. In British Columbia, the snails inhabit moist, well-vegetated mixed-wood forests and are often found in riparian areas along lakes, rivers, and creeks, especially where Cottonwoods are present. A well-developed litter layer and coarse woody debris on the forest floor provide hiding places and refuges from inclement weather. Historically, land conversions for residential and industrial developments and for agriculture have resulted in loss of habitat at lower elevations, especially along river valleys, lake shores, and highways. Habitats across the snails’ range continue to be modified and fragmented by forestry, road networks, expanding urban development, and increasing frequency and duration of droughts projected under climate change. [Updated by COSEWIC - Apr, 2017]

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Biology

Banded Tigersnail is an air-breathing (pulmonate), simultaneous hermaphrodite (possesses both male and female reproductive organs), egg-laying snail. Few details of the life history of the species in Canada are known. Mating probably occurs in mid-spring and mid-summer, and egg-laying in late spring and late summer. Hibernation extends from early October until April in temperate regions. Snails are prone to freezing in winter and dehydration in summer. They rely on sheltered refuges and snow cover to buffer them from freezing during winter. Dormancy in summer may occur during prolonged drought. Sexual maturity is probably reached at 2 – 3 years of age. The generation time is probably 5 - 6 years. Active dispersal for colonization of new areas is in the order of tens of metres over several years. Passive dispersal by flooding of rivers or transportation by birds is possible but has not been documented. There is no evidence that the species is transported by humans. [Updated by COSEWIC - Apr, 2017]

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Threats

In Canada, Banded Tigersnail exists at the northern limit of its range. Low dispersal ability and low physiological resistance to fluctuating environmental factors such as temperature and humidity are considered limiting factors. In Ontario, climate change represents an important but poorly understood threat to the snails through storms on Middle Island and erosion and flooding of forest on Pelee Island. Moreover, risk of droughts and extreme temperatures, resulting in spring frost, are a threat at all sites. Other threats include competition with introduced snails and slugs and increased predation pressure from introduced omnivorous Wild Turkeys and Ring-necked Pheasants on Pelee Island. On Middle Island, nesting native Double-crested Cormorants have severely altered habitats, resulting in alteration of soil chemistry, tree dieback, reduced plant species’ richness, and an increase in exotic species. Exotic plants and earthworms on Pelee Island also contribute to modification of the litter layer and habitat structure. Prescribed fire affects potential habitat. In British Columbia, threats include habitat loss, alteration, and fragmentation by logging, roads, urban development, and wildfires, as well as increased frequency and intensity of droughts, storms and flooding, as predicted under climate change. Prolonged summer droughts associated with climate change are likely to exacerbate the effects of logging and wildfires. Climate change and forest disturbance may facilitate the spread of introduced invertebrates such as slugs, snails, and ground beetles, which may compete with or prey on tigersnails. [Updated by COSEWIC - Apr, 2017]

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Protection

Federal Protection

The Eastern Banded Tigersnail is protected under the federal Species at Risk Act (SARA). More information about SARA, including how it protects individual species, is available in the Species at Risk Act: A Guide.

Provincial and Territorial Protection

To know if this species is protected by provincial or territorial laws, consult the provinces' and territories' websites.

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Documents

PLEASE NOTE: Not all COSEWIC reports are currently available on the SARA Public Registry. Most of the reports not yet available are status reports for species assessed by COSEWIC prior to May 2002. Other COSEWIC reports not yet available may include those species assessed as Extinct, Data Deficient or Not at Risk. In the meantime, they are available on request from the COSEWIC Secretariat.

5 record(s) found.

COSEWIC Status Reports

  • COSEWIC Assessment and Status Report on the Eastern Banded Tigersnail Anguispira kochi kochi and Western Banded Tigersnail Anguispira kochi occidentalis in Canada (2018-01-17)

    Banded Tigersnail is a large land snail (adult shell width 2.0 – 2.5 cm) with a globular, yellow to brown shell that has an opening in the centre when viewed from below and a light-coloured spiral band bordered by a darker band on either side. Variations include size, shell thickness, and colour of the shell, as well as the visibility of bands. Two subspecies are currently recognized: Anguispira kochi kochi on the Lake Erie islands in Ontario, and A. k. occidentalis in British Columbia. The Eastern and Western subspecies are part of the unique faunas of the Carolinian and northern Columbia Basin ecosystems, respectively, and have significance for biodiversity, research, and conservation. As part of the gastropod community in forest ecosystems, Banded Tigersnail plays a role in litter decomposition and nutrient cycling.

Response Statements

  • Response Statement - Eastern Banded Tigersnail (2018-01-18)

    This large terrestrial snail remains in small isolated habitat patches on Middle and Pelee islands, in Lake Erie. The loss of subpopulations on some smaller islands was probably due to habitat destruction from overabundant Double-crested Cormorants, which colonized the islands in the early 1980s, as well as human activities. Habitat loss and alteration on Pelee Island likely led to subpopulation declines and fragmentation. Climate change is the most serious threat.

Orders

  • Order Amending Schedule 1 to the Species at Risk Act (2021-09-01)

    The objectives of the Order Amending Schedule 1 to the Species at Risk Act (the Order) are to help maintain Canada's biodiversity and support the well-being of Canadian ecosystems by preventing wildlife species from becoming extirpated from Canada or extinct and to contribute to their recovery, as well as to respond to COSEWIC's recommendations.

COSEWIC Annual Reports

  • COSEWIC Annual Report 2016 to 2017 (2017-10-24)

    Over the past year COSEWIC re-examined the status of 40 wildlife species; of these, the majority (78 %) were reassessed at the same or lower level of risk. Of a total of 73 species assessed 11 were assigned the status of Not at Risk (8 re-assessments and 3 new assessments). To date and with the submission of this report, COSEWIC’s assessments now include 735 wildlife species in various risk categories including 321 Endangered, 172 Threatened, 219 Special Concern and 23 Extirpated (i.e. - no longer found in the wild in Canada). In addition 16 species have been assessed as Extinct, 58 have been designated as Data Deficient and 186 were assessed and assigned Not at Risk status.

Consultation Documents

  • Consultation on Amending the List of Species under the Species at Risk Act: Terrestrial Species January 2018 (2018-01-26)

    The Government of Canada is committed to preventing the disappearance of wildlife species at risk from our lands. As part of its strategy for realizing that commitment, on June 5, 2003, the Government of Canada proclaimed the Species at Risk Act (SARA). Attached to the Act is Schedule 1, the list of the species provided for under SARA, also called the List of Wildlife Species at Risk. Extirpated, Endangered and Threatened species on Schedule 1 benefit from the protection afforded by the prohibitions and from recovery planning requirements under SARA. Special Concern species benefit from its management planning requirements. Schedule 1 has grown from the original 233 to 555 wildlife species at risk. In 2017, final listing decisions were made for 44 terrestrial species and 15 aquatic species. Of these 59 species, 35 were new additions, sixteen were reclassifications, three had a change made to how they are defined, two were removed from Schedule 1, one was referred back to COSEWIC for further evaluation and two were the object of ‘do not list’ decisions. In 2017, on the recommendation of the Minister of the Environment, the Governor in Council approved listing proposals for 45 wildlife species. It is proposed that 21 species be added to Schedule 1, 11 be reclassified, 12 would have a change made to how they are defined, and one would be referred back to COSEWIC for further evaluation. The listing proposals were published in Canada Gazette, part I for a 30-day public comment period and final listing decisions for all 45 species are expected by August of 2018. Please submit your comments by May 22, 2018, for terrestrial species undergoing normal consultations and by October 22, 2018, for terrestrial species undergoing extended consultations. For a description of the consultation paths these species will undergo, please visit the Species at Risk Public Registry (SAR) website.
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