Addendum to the COSEWIC Status Report on the Lake Winnipeg Physa Physa sp. in Canada

Photo of the Lake Winnipeg Physa (see long description below).

Long description for cover photo

Photo of the Lake Winnipeg Physa, Physa sp., shell showing aperture. The shell is less than 10 millimetres long (length estimated from scale bar in image) and globose, with a depressed spire and thin lip.


Data deficient 2012

COSEWIC title

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. 2012. Addendum to the COSEWIC  status report on the Lake Winnipeg Physa Physa sp. in Canada. Committee on the Status of Endangered Wildlife in Canada. Ottawa. xx pp. (Species at Risk Public Registry).

Previous report(s):

COSEWIC. 2002. COSEWIC  assessment and status report on the Lake Winnipeg Physa Physasp. in Canada. Committee on the Status of Endangered Wildlife in Canada. Ottawa. vi + 24 pp.

Production note:
COSEWIC  would like to acknowledge Dr. Dwayne Lepitzki for writing the addendum to the status report on the Lake Winnipeg Physa, Physa sp., in Canada. This addendum was overseen and edited by Dr. Gerry Mackie, Co-chair of the COSEWIC  Molluscs Specialist Subcommittee.

Please note: This is an addendum to the COSEWIC  status report on the Lake Winnipeg Physa, physa sp., which was designated Endangered in 2002. Please refer to the 2002 report for more information on this species.

For additional copies contact:

COSEWIC  Secretariat
c/o Canadian Wildlife Service
Environment Canada
Ottawa, ON
K1A 0H3

Tel.: 819-953-3215
Fax: 819-994-3684
E-mail: COSEWIC/COSEPAC@ec.gc.ca
COSEWIC website

Également disponible en français sous le titre Addenda du COSEPACsur la Physe du lac Winnipeg (Physa sp.) au Canada.

©Her Majesty the Queen in Right of Canada, 2013.


COSEWIC Logo



COSEWIC Assessment Summary

Assessment Summary – November 2012

Common name
Lake Winnipeg Physa

Scientific name
Physa sp.

Status
Data Deficient

Reason for designation
This freshwater snail was described as being endemic to Lake Winnipeg, Manitoba and assessed as Endangered by COSEWIC  in 2002. Despite annual searches, the last observation of the taxon was in 2006. The taxonomic uncertainty and the lack of genetic material for further study have resulted in a designation of Data Deficient.

Occurrence
Manitoba

Status history
Designated Endangered in November 2002. Species considered in November 2012 and placed in the Data Deficient category.

 



COSEWIC Addendum to the COSEWIC Assessment and Status Report

Physa sp.(= Physella winnipegensis Pip 2004)

Lake Winnipeg Physa

Physe du lac Winnipeg

Range of occurrence in Canada (province/territory/ocean): Manitoba

Previous COSEWIC  Assessment:

Status category: Endangered (E)

Date of last assessment: November 2002

Reason for designation at last assessment:
Populations of this Canadian endemic are confined to Lake Winnipeg, where there are continuing declines in extent of occurrence, area of occupancy and extent of habitat due to habitat alteration, human disturbance and quality of habitat. Evidence suggests that nutrients and contaminants from sewage lagoons, industries, waste storage facilities and/or landfills are contributing to the declines.

Criteria applied at last assessment: B1ab (i,ii,iii,iv,v)+2ab (i,ii,iii,iv,v)

If the earlier version of criteria was applied1, provide correspondence to current version of the criteria:

 

Wildlife species:

Change in eligibility, taxonomy or designatable units:yes and no

Explanation:
See text below for explanation (did not fit within text box).

1 An earlier version of the quantitative criteria was used by COSEWIC  from October 1999 to May 2001 and is available on the COSEWIC  website: Wildlife Species Assessment

 



Taxonomic Validity

When this snail was originally assessed (COSEWIC  2002), it had not been formally described and was named Physa sp., Lake Winnipeg Physa. COSEWIC  (2003) sent the assessment to the CESCC(Canadian Endangered Species Conservation Council) in May 2003; the Minister of the Environment (M of E) provided a response statement on 21 April 2004 stating that consultations would be undertaken for a period of 9 months and that results of the consultation would be included when the COSEWIC  assessment was forwarded to the GIC (Governor in Council) (M of E 2004). In March 2004, the snail was included in the consultation booklet (Fisheries and Oceans Canada 2004). On 14 July 2005, the GIC acknowledged receipt of the species’ assessment as endangered (Government of Canada 2005).

On 6 April 2006, the GIC referred the assessment of the Lake Winnipeg Physa back to COSEWIC  “for further information and consideration” (Government of Canada 2006). The reason given was that “the assessment for the Lake Winnipeg Physa is based on a scientific paper that has not been peer reviewed and does not adequately define whether the physa is a distinct species or a variant of a much more abundant species found elsewhere”.

Specifically, “COSEWIC  will be asked to review and respond as to whether appropriate and clear speciation and definition of designatable units has been used for …. the Lake Winnipeg Physa”, and “whether there has been appropriate use of available abundance data and distributional information for ….. the Lake Winnipeg Physa”. This assertion was because Pip (2004) had formally described the snail as Physella winnipegensis based on shell morphology and mantle digitations in the non-peered review journal Visaya produced by Conchology Inc., which is now available through the ConchBooks publishing house. The holotype had been deposited (Canadian Museum of Nature CMNML 093695) and was subsequently observed and/or photographed by R. Forsyth and D. Lepitzki on 24 November 2008 but the remaining specimens were retained in the describing author’s personal collection which will be donated to the CMN (Pip 2004). There is one empty Physella winnipegensis shell identified and collected by E. Pip on 3 September 2004 from beachwash along Victoria Beach, Lake Winnipeg, deposited at The Manitoba Museum (Catalogue number 2.4-6514) (Mooi pers. comm. 2011).

COSEWIC  (2007) confirmed its original assessment for the species as endangered in the annual report to the Minister and the CESCCstating that the “original status reports for these species contain the information on which these assessments were based”, that “COSEWIC  was not provided with new information that would likely lead to a change in the status”, and that “in the absence of such information, it is unlikely that COSEWIC  would reassess the status of a species at risk”. COSEWIC’s initial decision was stated as being communicated to the Minister on 24 May 2006 prior to the reception of the detailed rationale communicated to the Chair of COSEWIC  from the Department of Fisheries and Oceans on 29 June 2006 (COSEWIC  2007). Appendix II of the 2007 Annual COSEWIC  report provides details on the rationale DFO used to refer the species back to COSEWIC  and COSEWIC’s response. COSEWIC  (2007) concluded that a description of a new species does not have to appear in a peer-reviewed journal in order to be valid or recognized under the International Code of Zoological Nomenclature. It was also stated that “the Molluscs Species Specialist Subcommittee (SSC) is unanimous in its opinion that this is a distinct species and not a ‘variant’ of another species” (COSEWIC  2007). However, given new information and uncertainties, the unanimous opinion of the Molluscs SSC has been updated (see below for SSC’s recommendation on status)

The 18 March 2007 response statement from the Minister of the Environment (M of E 2007) states that in December 2006 COSEWIC  reaffirmed the original assessment without reassessing the species. “In the coming months, the Minister of the Environment will forward the COSEWIC  assessment of the Lake Winnipeg Physa Snail to the Governor in Council” (M of E 2007). On 30 September 2010, the GIC did acknowledge receipt of the COSEWIC  assessment of the snail (Government of Canada 2010).

In the intervening time, Pip and Franck (2008) published an mtDNAstudy which concluded that Physa (sensulato)winnipegensis formed a distinct branch within the Physa acuta clade. On 9 March 2009, Fisheries and Oceans Canada (DFO) convened a regional science advisory meeting via teleconference to assess the taxonomic validity of the Lake Winnipeg Physa (DFO 2009). One of the lines of evidence this group of various experts, including E. Pip and others outside of DFO, discussed were the Pip (2004) and Pip and Franck (2008) publications. The conclusion DFO reached (Government of Canada 2011) was that the snail was not a distinct physa species and was therefore ineligible for listing under the Species at Risk Act. Other conclusions in the 23 June 2011 order giving notice of the decision by the GIC to not add the Lake Winnipeg Physa to the list of endangered species included that the meeting proceedings “indicated that there was insufficient evidence to support the conclusion that the Lake Winnipeg Physa was a distinct taxonomic unit. Most participants agreed that the Lake Winnipeg Physa was a local variety and not considered to be at risk. Considering this lack of clarity concerning the taxonomy of the animal, it is premature to contemplateadding it to the list.

One of the participants in the regional science advisory meeting (DFO 2009) has subsequently published a paper that included P. winnipegensis among the 19 other taxa they synonymized with P. acuta (Wethington et al. 2009). Unfortunately, no mtDNA data from P. winnipegensisappear to be included in the phylogenetic figures in the paper. In addition, the only identical genebank accession numbers appearing in both Pip and Franck (2008) and Wethington et al. (2009) are AY651233 and AY651234, for snails collected from South Carolina, which both publications suggest are in the P. pomilia clade or are P. pomilia, respectively. Therefore the rationale for synonymizing P. winnipegensis with P. acuta is not shown in Wethington et al. (2009) although it is mentioned that Taylor (2003) did publish an extensive synonymy. Indeed Taylor (2003), who uses Haitia as the generic name for P. acuta, does provide an extensive list; however, some of the species that Wethington et al. (2009) list as synonyms for P. acuta were retained as full species by Taylor (2003). None of the additional publications which Wethington et al. (2009) refer to as adding to the synonymy given by Taylor (2003) include P. winnipegensis. Taylor (pers. comm. 2005) did state to Pip in an email forwarded to the status reassessment writer that he had received a copy of the description by Pip with illustrations and that “I certainly believe that it is a valid species, and a wonderful discovery!”. Pip (pers. comm. 2011) also stated that Taylor subsequently came to Manitoba in 2005 and examined the snail in person after his monograph (Taylor 2003) was published. Taylor died on 3 August 2006 (Kabat and Johnson 2008).

The Gastropod Subcommittee of the American Fisheries Society (AFS) Endangered Species Committee submitted a manuscript on the conservation status of North American freshwater gastropods in January 2012; publication is expected soon (Johnson et al. in press). Due to the taxonomic instability of the Physidae, they include some new species by Taylor (2003), Pip (2004 = Physella winnipegensis), and Wethington et al. (2009) but instead of following the systematics proposed by Taylor (2003), follow the classification of Turgeon et al. (1998).

In summary, while there is new information on the genetics of the Lake Winnipeg Physa, it is unclear if the species is a valid taxon and it is uncertain if the taxon is eligible for reassessment by COSEWIC.



Designatable Units

The COSEWIC  concept of designatable units was discussed by the DFO science advisory committee (DFO 2009). The report states:

“The guidelines used by COSEWIC  for recognizing designatable units below the species level were used during the advisory meeting to provide context for the discussions. However, DFO is obliged to recognize taxonomic validity on the basis of the definition of “wildlife species” in SARA. Thus the purpose of the meeting was to determine, to the extent possible, whether Lake Winnipeg Physa is a valid wildlife species as defined under SARA.”

However, the third question posed at the advisory meeting was: “Is this taxonomic entity “significant” as defined by COSEWIC  for Designatable Units”. Conclusions reached on this question were:

  • some participants thought it would be useful to delay the decision for SARA listing until new microsatellite markers were developed to “help resolve the taxonomic quagmire in the P. acuta clade”;
  • most participants agreed that the currently available genetic and morphological data did not clearly demonstrate that the taxon is fundamentally distinctive from other similar physids, but the breeding behaviour described by E. Pip “suggests these snails may be distinctly different in that regard.”
  • participants did not agree whether the taxon is ecologically interchangeable and irreplaceable. Unpublished data reported by E. Pip suggested that similar ecological conditions exist in other lakes where P. acuta/P. integraoccur yet Lake Winnipeg Physawas confined to Lake Winnipeg and numbers had declined, potentially to zero; therefore, the taxon could be considered ecologically unique and irreplaceable. Most participants, however, thought it is not possible to determine if the taxon was ecologically unique and therefore an irreplaceable component of Canada’s biodiversity.
  • most participants concluded that while it is possible that the taxon might be a distinctive taxonomic unit because of its breeding behaviour, a possibly inherited trait, this could not be confirmed because multiple generations had not been observed and the breeding behaviour had not been quantified or described in the literature.
  • because the SARAdefinition of “wildlife species”, which DFO is obligated to use, does not include unique behaviour as a defining characteristic, the taxon does “not appear to be a taxonomic unit regardless of their potentially distinctive breeding behavior”.

Nothing has been published on the reported unique breeding behaviour of Lake Winnipeg Physa; however, E. Pip presented some unpublished data at the advisory meeting convened by DFO (DFO 2009). In May 2001, 2002, and 2003 Pip observed the snails congregating on a few boulders within a 2-3 sq. m.area where they mated and laid egg cases over a period of several days. In contrast she observed P. integra to be distributed evenly during the breeding season and to be not particular where they laid their eggs. There are no reports in the literature about any other physid showing this breeding behaviour but the advisory participants cautioned that daily and intensive field observations would be required to document such behaviour (DFO 2009).

The COSEWIC  guidelines for the identification of designatable units (DUs: Appendix F5) have two components:

  1. Subspecies or varieties, where a DU may be recognized if it represents a named subspecies or variety
  2. A discrete and evolutionarily significant population, where a population or group of populations may be recognized if it has attributes that make it “discrete” and evolutionarily “significant” relative to other populations.

The first component, a named subspecies or variety does not help decide if the taxon is eligible for COSEWIC  assessment. The Lake Winnipeg Physa has been described not as a subspecies or variety but as a full species (Pip 2004; Pip and Franck 2008). The guidelines do state that “COSEWIC  may choose not to recognize a named subspecies or variety as a DU if current scientific data do not support its validity.” However, conclusions from the available genetic evidence are disputed and it is uncertain if P. winnipegensis is a valid taxon.

The second component has two parts: discreteness and significance, both of which must be present.

Discreteness may be considered based on one or more of the following criteria (guidelines shown verbatim in italics, bold and indented):

  • 1. Evidence of genetic distinctiveness including, but not limited to, inherited traits (e.g. morphology, life history, behaviour) and/or neutral genetic markers (e.g. allozymes, DNA microsatellites, DNA restriction fragment length polymorphisms (RFLPs), DNAsequences).

For Lake Winnipeg Physa, the breeding behaviour may be distinctive but cannot be confirmed (DFO 2009) and morphological and genetic data are disputed (DFO 2009). The lack of any living individuals being found since 2006 (Population Information) makes further research problematic. The scientific advisory report (DFO 2009) states the decision on whether the taxon in question is a separate monophyletic group “may, at least in part, rely on whether one is a proponent of lumping or splitting taxonomic groups. At one extreme all groups within the P. acuta clade could be lumped into one species and at the other extreme each group could constitute an individual species. It comes down to the fundamental question of whether a group is sufficiently distinct to warrant identifying it as a taxonomic unit based upon the personal training, experience, and philosophy of the individual taxonomist.”

  • 2. Natural disjunction between substantial portions of the species’ geographic range, such that movement of individuals between separated regions has been severely limited for an extended period of time and is not likely in the foreseeable future and where the disjunction is likely to favour the evolution of local adaptations.

Lake Winnipeg Physa are endemic to Lake Winnipeg but co-occur with other physids including P. gyrina and P. integra; the presence of Lake Winnipeg Physa was positively (Chi-square, P<0.05) associated with both P. gyrina and P.integra in the lake (COSEWIC  2002). Similarly, DFO (2009) concludes “Lake Winnipeg Physa and P. integra are sympatric, though the former is limited to the south basin of Lake Winnipeg whereas the latter has a much broader distribution which includes various areas in central Canada, from Alberta to Ontario, and Minnesota.” However, it is acknowledged that “their microhabitat is different” with the former preferring “exposed, wind-swept [should be wave-swept] rocks” while the latter prefers “more sheltered locations under rocks”.

The third COSEWIC  guideline on discreteness, is not applicable to Lake Winnipeg Physa as it is endemic to one lake:

  • 3. Occupation of differing eco-geographic regions that are relevant to the species and reflect historical or genetic distinction, as may be depicted on an appropriate ecozone or biogeographic zone map. Some dispersal may occur between regions, but it is insufficient to prevent local adaptation

The COSEWIC  guidelines on DUs also include significance, which is considered after discreteness is found to apply to the taxon in question. Again, only one of the following criteria for significance need apply.

  • 1. Evidence that the discrete population or group of populations differs markedly from others in genetic characteristics thought to reflect relatively deep intraspecific phylogenetic divergence. Such differences would typically be manifested as qualitative genetic differences at relatively slow-evolving markers (e.g. fixed differences in mitochondrial or nuclear DNA sequences or fixed differences in alleles at multiple nuclear loci). Quantitative (frequency) differences of shared alleles, especially for rapidly-evolving markers such as microsatellites, generally would not be sufficient to meet thiscriterion.

For Lake Winnipeg Physa, genetic data currently available are disputed (DFO 2009).

  • 2. Persistence of the discrete population or group of populations in an ecological setting unusual or unique to the species, such that it is likely or known to have given rise to local adaptations.

For Lake Winnipeg Physa, its microhabitat differs somewhat from its nearest genetic neighbour and it appears to have an unusual breeding behaviour (DFO2009).

Criteria 3 and 4 for evolutionary significance are not applicable to Lake Winnipeg Physa:

  • 3. Evidence that the discrete population or group of populations represents the only surviving naturaloccurrence of a species that is more abundant elsewhere as an introduced population outside of its historical range.
  • 4. Evidence that the loss of the discrete population or group of populations would result in anextensive gap in the range of the species in Canada.

In summary, morphological and genetic evidence for discreteness and significance of Lake Winnipeg Physa is disputed. There is an acknowledged unique breeding behaviour and microhabitat preference that has been proposed that could be inherited and may have led to local adaptation. However, these latter lines of evidence are largely based on personal observations and unpublished data.

Two recent COSEWIC  reassessments may be relevant to this discussion. The Aurora Trout (Salvenlinus fontinalis timagamiensis) was recently found to be ineligible because new genetic and breeding data indicate it was not a valid designatable unit within Brook Trout (COSEWIC  2011). In contrast, three DUs were approved by COSEWIC  for the Yellow-breasted Chat (Icteria virens). The two western DUs, which are the same subspecies (I. virens virens), were separated with evidence for “discreteness” being the separation by the Rocky Mountains and evidence for “significance” being local adaptation for different nesting substrates (COSEWIC  in press).

In conclusion, the lack of finding this entity alive since 2006 (see Population Information) and the apparent lack of any preserved material, makes the resolution of its eligibility and taxonomic validity impossible at this time.

Range:

Change in Extent of Occurrence (EO): yes  

Change in Index of Area of Occupancy (IAO) : yes

Change in number of known or inferred current locations*: yes  

Significant new survey information yes

Explanation:
COSEWIC  (2002), Pip (2004), and Pip and Franck (2008) state that this snail is endemic to Lake Winnipeg, Manitoba. The species was known to occupy only five sites in 2001 and to have disappeared from another two historical sites, having first been observed in 1961 (Figure 1; COSEWIC  2002; Pip 2004). The type locality is Victoria Beach (Pip 2004) with two individuals from Sunset Beach being subject to mtDNAanalyses (Pip and Franck 2008).

Annual searches for this taxon (see Population Information) after 2006 have failed to find any live individuals. Therefore, it appears that there has been a continuing decline in EO, IAO, and number of locations, given the best available information. These declines factored into the original COSEWIC  assessment of endangered (COSEWIC  2002).

* Use the IUCNdefinition of “location”

 


Population Information:

Change in number of mature individuals: yes

Change in total population trend: no

Change in severity of population fragmentation: no  

Change in trend in area and/or quality of habitat: no  

Significant new survey information yes

Explanation:

The only published record on population size of Lake Winnipeg Physa is a reference to unpublished data from Pip in Pip and Franck (2008): “it is currently estimated at <500 individuals”. No estimates were included in the original COSEWIC  status report (COSEWIC  2002).

New information on the population and distribution of this species has been obtained only via personal communications.

A search for physids in Lake Winnipeg occurred during the summer of 2005 under a Habitat Stewardship Program through the Lake Winnipeg Consortium (Morris pers. comm.2011). Some P. winnipegensis were identified and observed by E. Pip and the contractor K. Scott but were not collected. Scott did some additional searches and collecting in more remote areas in the south basin and narrows of Lake Winnipeg to try and find new sites containing the snail (Scott in Morris pers. comm. 2011). These other physids collected by Scott in the summer of 2005 were later identified by Dwight Taylor as being Physella gyrina, not Physella winnipegensis, and will be catalogued soon for inclusion in The Manitoba Museum in Winnipeg (Mooi pers. comm. 2011).

Pip (pers. comm.2008) stated that weekly surveys from ice-out to freeze-up yielded the following results:

2006: 5 live individuals (adult)
2007: 4 empty shells, no live
2008: zero so far with searches having been conducted in May, “the best time to see them”.

Pip has “kept detailed population records for each season” (Pip pers. comm. 2 July 2011). She states that the last three living individuals were observed in May 2006 at the Sunset Beach site but no egg cases were found that season or thereafter. The Sunset Beach site has since been converted into high-density residential development which limits the chance of re-establishment if an extant population was found. Later (9 Sept 2011) it was confirmed that another two live individuals were observed in 2006 at another site, with the Sunset Beach site being where the primary population had been. These two snails were in poor shape. “Very extensive and repeated searches have been made at all of the 2001 sites, as well as elsewhere”. She also stated that these data, including the details on search effort, remain her property until she publishes as fieldwork was done under her own expense. The last correspondence (13 October 2011) stated that “weekly searches have been made at all their old sites for the last 5 years and also much additional area has been searched, but I think they are truly gone.”

For a discussion about the lack of a change in the quality of habitat, see Threats.

 


Threats:

Change in nature and/or severity of threats: no

Explanation:

The threats identified in the original status report (COSEWIC  2002) continue. Identified primary threats included nutrient influx from cottage developments, urban centres and livestock operations, and habitat disruption due to recreational use and shoreline modifications. The influx of nutrients and silt from intensive logging and increased shoreline erosion due to water-level regulation were also identified.

The first comprehensive assessment of the physical, chemical, and biological characteristics of Lake Winnipeg - the State of Lake Winnipeg Report - was released to the public in July 2011 (Manitoba Water Stewardship 2012). It concluded that water quality of Lake Winnipeg had deteriorated over the last few decades due to accelerated nutrient enrichment (Environment Canada and Manitoba Water Stewardship 2011). Increasing phosphorus and nitrogen loading from diffuse and point sources have resulted in an increase in frequency and intensity of algal blooms. The Government of Manitoba (2011) acknowledged that these excessive nutrients enter Lake Winnipeg from many urban and rural sources including: excess fertilizers, flooded lands, livestock manure, loss of wetlands, inadequate treated municipal sewage, and substandard septic systems.

The type locality, Victoria Beach, was subject to severe beach erosion during storms in October 2010. Attempts by local cottagers to control beach erosion by adding boulders and gravel to the beach led to stop work orders being issued by the province for work that was being done on Crown land (see Simonson 2011 and search for “Victoria Beach erosion” on web for numerous press articles). The effects of the storms and the resulting actions are uncertain given that P. winnipegensis was last observed at Victoria Beach from 1976-1984 (COSEWIC  2002).

 

Protection:

Change in effective protection:  no

Explanation:

Subsequent to the COSEWIC  (2002) assessment as endangered, the species has not been added to the SARA list (Government of Canada 2011) (see Taxonomic Validity).

However, in June 2011 the Province of Manitoba passed the Save Lake Winnipeg Act (Government of Manitoba 2011) This Act amended five other Acts (Crown Lands Act; Environment Act; Mines and Minerals Act; Planning Act; Water Protection) and allowed the designation of areas of Crown land as provincially significant wetlands, expanded the hog barn moratorium to all of Manitoba, prohibited the spreading of manure in the winter, placed a moratorium on peat mining for two years, required the preparation of drinking water and wastewater management plans for certain jurisdictions, and required the City of Winnipeg to modify or replace a wastewater treatment plant.

 

Rescue Effect:

Change in evidence of rescue effect: no

Explanation:
By definition, an endemic species cannot be rescued.

 

Quantitative Analysis:

Change in estimated probability of extirpation: no

Details:
No quantitative analyses have been done.

 

Summary and Additional Considerations:[e.g., recovery efforts]

Drafting of a Recovery Strategy was initiated shortly after the original COSEWIC  assessment but efforts have stalled because the species was eventually not added to the SARA list (see Taxonomic Validity).



Acknowledgements and authorities contacted:

Thanks are extended to Dr. Eva Pip for her assistance and sharing of her unpublished data.

The following individuals were contacted via email.
*Denotes that information was provided by authority contacted.

*Watkins, William. December 2011. Conservation Zoologist, Wildlife and Ecosystem Protection Branch, Manitoba Conservation, Winnipeg, Manitoba.

*Whelan, Christie. December 2011. Science Advisor, Fish Population Science, Fisheries and Oceans Canada. Ottawa, Ontario.

*Boles, Ruben. December 2011. Biologist, Species Assessment, Species Population and Standards Management, Canadian Wildlife Service, Environment Canada, Gatineau, Quebec.

Nantel, Patrick. December 2011. Conservation Biologist, Species at Risk Program, Ecological Integrity Branch, Parks Canada, Gatineau, Quebec.



Information sources:

COSEWIC. 2002. COSEWIC  assessment and status report on the Lake Winnipeg Physa Physa sp. in Canada. Committee on the Status of Endangered Wildlife in Canada. Ottawa. vi + 21 pp.

COSEWIC. 2003. Annual report to the Canadian Endangered Species Conservation Council, May 2003. 56 pp.

COSEWIC. 2007. COSEWIC  annual report presented to the Minister of the Environment and the Canadian Endangered Species Conservation Council. 30 August. 119 pp.

COSEWIC. 2011. COSEWIC  update status report on the Aurora Trout Salvelinus fontinalis timagamiensis. 2-month Interim Report with additional minor edits as approved by COSEWIC, May 2011 Wildlife Species Assessment Meeting. Committee on the Status of Endangered Wildlife in Canada. Ottawa. ix + 25 pp.

COSEWIC. In press. COSEWIC  assessment and status report on the Yellow-breasted Chat auricollis subspeciesIcteria viens auricollis and the Yellow-breasted Chat virens subspecies Icteria virens virensin Canada. Committee on the Status of Endangered Wildlife in Canada. Ottawa. xvi = 51 pp (Species at Risk Public Registry).

DFO(Fisheries and Oceans Canada). 2009. Peer review to assess the taxonomic validity of the Lake Winnipeg Physa. DFO Canadian Science Advisory Secretariat Science Response 2009/004. 11 pp.

Environment Canada and Manitoba Water Stewardship. 2011. State of Lake Winnipeg Report: 1999 to 2007

Fisheries and Oceans Canada. 2004. Consultation on amending the list of species under the Species at Risk Act, Central and Arctic Region. March. 17 pp.

Government of Canada. 2005. Canada Gazette Part II. 139(15):1750-1801.

Government of Canada. 2006. Canada Gazette Part II. 140(8):252-294.

Government of Canada. 2010. Canada Gazette Part II. 144(21):1806-1974.

Government of Canada. 2011. Canada Gazette Part II. 145(14):1202-1411.

Government of Manitoba. 2011. Chapter 36, The Save Lake Winnipeg Act (PDF, 196 KB). [Accessed 7 February 2012].

Johnson, P.D., A.E. Bogan, K.M. Brown, N.M. Burkhead, J.R. Cordeiro, J.T. Garner, P.D. Hartfield, D.A.W. Lepitzki, G.R. Mackie, E. Pip, T.A. Tarpley, J.R. Tiemann, N.V. Whelan, and E.E. Strong. In press. Conservation status of freshwater gastropods of Canada and the United States. Fisheries.

Kabat, A.R., and R.I. Johnson. 2008. Dwight Willard Taylor (1932-2006): his life and malacological research. Malacologia 50(1-2):175-218.

Manitoba Water Stewardship. 2012. State of Lake Winnipeg Report. [Accessed 7 February 2012].

M of E (Minister of the Environment). 2004. Response statement for Lake Winnipeg Physa (PDF, 4.24 KB).

M of E (Minister of the Environment). 2007. Response statement – Lake Winnipeg Physa (PDF, 13.3 KB).

Mooi, R., pers. comm. 2011. Email correspondence with D. Lepitzki.Curator of Zoology, The Manitoba Museum, Winnipeg, Manitoba. 13, 15 December 2011.

Morris, T., pers. comm. 2011. Email correspondence with D. Lepitzki. Research Scientist, Fisheries and Oceans Canada, Great Lakes Laboratory for Fisheries and Aquatic Sciences, Burlington, Ontario. 19, 20 October 2011.

Pip, E. 2004. A new species of Physella (Gastropoda: Physidae) endemic to Lake Winnipeg, Canada. Visaya 1(2)(December 2004):42- 48.

Pip, E., pers. comm.2008, 2011. Email correspondence with D. Lepitzki.Department of Biology, University of Winnipeg, original COSEWIC  status report writer. 12 June 2008; 2 July, 9 September, 13 October 2011.

Pip, E., and J.P.C. Franck. 2008. Molecular phylogenetics of central Canadian Physidae(Pulmonata: Basommatophora). Canadian Journal of Zoology 86:10-16.

Simonson, I. 2011. Victoria Beach. Cottage July/August 20(5):18-19.

Taylor, D.W. 2003. Introduction to Physidae (Gastropoda: Hydrophila) biogeography, classification, morphology. Revista de Biologia Tropical, International Journal of Tropical Biology and Conservation 51 (Supplement 1):1-287.

Taylor, D., pers. comm. 2005. Email correspondence to E. Pip, 12/10/2005 forwarded to D. Lepitzki 19 September 2011.

Turgeon, D.D., J.F. Quinn Jr., A.E. Bogan, E.V. Coan, F.G. Hochberg, W.G. Lyons, P.M. Mikkelsen, R.J. Neves, C.F.E. Roper, G. Rosenberg, B. Roth, A. Scheltema, F.G. Thompson, M. Vecchione, and J.D. Williams. 1998. Common and scientific names of aquatic invertebrates from the United States and Canada: Mollusks, 2nd edition. American Fisheries Society, Special Publication 26:ix + 526 pp.

Wethington, A.R., J. Wise, and R.T. Dillon Jr. 2009. Genetic and morphological characterization of the Physidae of South Carolina (Gastropoda: Pulmonata: Basommatophora), with a description of a new species. The Nautilus 123(4):282-292.

 


Figure 1. Known distribution of P. winnipegensis as of 2001 (from COSEWIC 2002).

Map showing the five locations where Physa sp. was found in 2001 (see long description below).

Description of Figure 1

Map showing the five locations (black filled circles) where Physa sp. was found in 2001. Two historical sites are also indicated (black filled triangles).



Technical Summary

Physa sp. (= Physella winnipegensis Pip 2004)
Lake Winnipeg Physa
Physe du lac Winnipeg
Range of occurrence in Canada (province/territory/ocean): Manitoba

Demographic Information

Generation time (usually average age of parents in the population; indicate if another method of estimating generation time indicated in the IUCNguidelines(2008) is being used)
Typically, physids are an annual species.
> 1yr
Is there an observed continuing decline in number of mature individuals?
Annual searches since 2006 have failed to find any live individuals
Not applicable (NA)
Estimated percent of continuing decline in total number of mature individuals within 5 years or 2 generations
Annual searches since 2006 have failed to find any live individuals.
NA
Observed percent reduction in total number of mature individuals over the last 10 years.
Annual searches since 2006 have failed to find any live individuals.
100% observed decline over the last 10 years
Suspected percent reduction in total number of mature individuals over the next 10 years or 3 generations.
Annual searches since 2006 have failed to find any live individuals.
NA
Observed percent reduction in total number of mature individuals over any 10 year period, over a time period including both the past and the future.
Annual searches since 2006 have failed to find any live individuals.
100% observed decline
Are the causes of the decline clearly reversible and understood and ceased?
No
Are there extreme fluctuations in number of mature individuals?
Annual searches since 2006 have failed to find any live individuals.
Unknown

 

Extent and Occupancy Information

Estimated extent of occurrence
Annual searches since 2006 have failed to find any live individuals.
0 km2
Index of area of occupancy (IAO) (Always report 2x2 grid value).
Annual searches since 2006 have failed to find any live individuals.
0 km2
Is the total population severely fragmented?
Annual searches since 2006 have failed to find any live individuals.
NA
Number of locations*
Annual searches since 2006 have failed to find any live individuals.
0
Is there an observed continuing decline in extent of occurrence?
Annual searches since 2006 have failed to find any live individuals.
NA
Is there an observed continuing decline in index of area of occupancy?
Annual searches since 2006 have failed to find any live individuals.
NA
Is there an observed continuing decline in number of populations?
Annual searches since 2006 have failed to find any live individuals.
NA
Is there an observed continuing decline in number of locations*?
Annual searches since 2006 have failed to find any live individuals.
NA
Is there an observed continuing decline in quality of habitat?
A continuing decline in habitat quality is observed.
Yes
Are there extreme fluctuations in number of populations?
Annual searches since 2006 have failed to find any live individuals.
NA
Are there extreme fluctuations in number of locations*?
Annual searches since 2006 have failed to find any live individuals.
NA
Are there extreme fluctuations in extent of occurrence?
Annual searches since 2006 have failed to find any live individuals.
NA
Are there extreme fluctuations in index of area of occupancy?
Annual searches since 2006 have failed to find any live individuals.
NA

* See Definitions and Abbreviations on COSEWIC  website and IUCN2010 for more information on this term.

 

Number of Mature Individuals (in each population)

PopulationN Mature Individuals
Annual searches since 2006 have failed to find any live individuals.0
Total0

 

Quantitative Analysis

Probability of extinction in the wild is at least [20% within 20 years or 5 generations, or 10% within 100 years]. NA

Quantitative analyses have not been done; annual searches since 2006 have failed to find any live individuals.

 

Threats (actual or imminent, to populations or habitats)

Degraded water quality due to various point and non-point sources including those from urban, rural, and agricultural activities; human-caused habitat disturbance and modification.

 

Rescue Effect (immigration from outside Canada)

Status of outside population(s)? Not applicable; is an endemic species.

Is immigration known or possible? No
Would immigrants be adapted to survive in Canada? NA
Is there sufficient habitat for immigrants in Canada? NA
Is rescue from outside populations likely? No

 

Data Sensitive Species

Is this a data sensitive species? NA

Annual searches since 2006 have failed to find any live individuals.

 

Status History

Designated Endangered in November 2002. Species considered in November 2012 and placed in the Data Deficient category. Designated Endangered in November 2002. Species considered in November 2012 and placed in the Data Deficient category.

 

Status and Reasons for Designation

Status: Data Deficient

Alpha-numeric Code: Not applicable

Reasons for Designation: This freshwater snail was described as being endemic to Lake Winnipeg, Manitoba and assessed as Endangered by COSEWIC  in 2002. Despite annual searches, the last observation of the taxon was in 2006. The taxonomic uncertainty and the lack of genetic material for further study have resulted in a designation of Data Deficient.

 

Applicability of Criteria

Criterion A
(Decline in Total Number of Mature Individuals): Not applicable.
Criterion B
(Small Distribution Range and Decline or Fluctuation): Not applicable.
Criterion C
(Small and Declining Number of Mature Individuals): Not applicable.
Criterion D
(Very Small or Restricted Total Population): Not applicable
Criterion E
(Quantitative Analysis): Not applicable.

 

COSEWIC History
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. On June 5, 2003, the Species at Risk Act (SARA) was proclaimed. SARA establishes COSEWIC  as an advisory body ensuring that species will continue to be assessed under a rigorous and independent scientific process.

COSEWIC Mandate
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.

COSEWIC Membership
COSEWIC  comprises 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.

Definitions (2012)

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.

* 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. Definition of the (DD) category revised in 2006.

Environment Canada - Canadian Wildlife Services - Government of Canada

The Canadian Wildlife Service, Environment Canada, provides full administrative and financial support to the COSEWIC  Secretariat.