Toothcup (Rotala ramosior): COSEWIC assessment status report 2014

Toothcup
Toothcup
Photo: S.R. Brinker on 30 August 2011 © 2015

Great Lakes Plains population – Threatened
Southern Mountain population – Endangered
2014

Table of Contents

List of Figures

List of Tables

Document Information

COSEWIC
Committee on the Status
of Endangered Wildlife
in Canada

COSEWIC logo

COSEPAC
Comité sur la situation
des espèces en péril
au Cananda

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:

COSEWIC. 2014. COSEWIC assessment and status report on the Toothcup Rotala ramosior, Great Lakes population and Southern Mountain population,in Canada. Committee on the Status of Endangered Wildlife in Canada. Ottawa. xv + 39 pp. (Species at Risk Public Registry).

Previous report(s):

COSEWIC. 2000. COSEWIC assessment and status report on the toothcup Rotala ramosior in Canada. Committee on the Status of Endangered Wildlife in Canada. Ottawa. vi + 19 pp.

Douglas, G.W., and M.J. Oldham. 1999. COSEWIC status report on the toothcup Rotala ramosior in Canada, in COSEWIC assessment and status report on the toothcup Rotala ramosior in Canada. Committee on the Status of Endangered Wildlife in Canada. Ottawa.  1-19 pp.

Production note:

COSEWIC would like to acknowledge Sam Brinker and Terry McIntosh for writing the status report on the Toothcup, Rotala ramosior, Great Lakes Plains population and Southern Mountain population, in Canada, prepared under contract with Environment Canada. This report was overseen and edited by Jeannette Whitton and Bruce Bennett, Co-chairs of the COSEWIC Vascular Plants Specialist Subcommittee.

For additional copies contact:

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

Tel.: 819-938-4125
Fax: 819-938-3984
E-mail: COSEWIC E-mail
Website: COSEWIC

Également disponible en français sous le titre Ếvaluation et Rapport de situation du COSEPAC sur le Rotala rameux (Rotala ramosior), population des plaines des Grands Lacs et la population des montagnes du Sud, au Canada.

Cover illustration/photo:

Toothcup -- Photo credit: Sprawling Toothcup plant at Puzzle Lake, Ontario (photo by S.R. Brinker on 30 August 2011).

COSEWIC Assessment Summary

Assessment Summary – November 2014

Common name
Toothcup - Great Lakes Plains population
Scientific name
Rotala ramosior
Status
Threatened
Reason for designation
This annual plant is known from the shores of only two lakes at the southern edge of the Canadian Shield in southeastern Ontario. Year-to-year fluctuations in water levels along the lakeshore impact the abundance of plants. Impacts from development, recreational boating activities, and manipulation of water levels have the potential to reduce the number of individuals.
Occurrence
Ontario
Status history
The species was considered a single unit and designated Endangered in April 1999. Status re-examined and confirmed in May 2000. Split into two populations in November 2014. The Great Lakes Plains population was designated Threatened in November 2014.
Common name
Toothcup - Southern Mountain population
Scientific name
Rotala ramosior
Status
Endangered
Reason for designation
This annual plant is known from just two local populations in the Southern Interior of British Columbia. Some locations have been lost as a result of shoreline development; at present, this species is limited by the availability of suitable seasonally wet sites, and threatened by invasive exotic plant species.
Occurrence
British Columbia
Status history
The species was considered a single unit and designated Endangered in April 1999. Status re-examined and confirmed in May 2000. Split into two populations in November 2014. The Southern Mountain population was designated Endangered in November 2014.

COSEWIC Executive Summary

Toothcup
Rotala ramosior

Great Lakes Plains population
Southern Mountain population

Wildlife Species Description and Significance

Toothcup is a low growing annual plant in the loosestrife family (Lythraceae). Its small flowers are sessile, and usually solitary in the leaf axils. Flowers usually have 4 white or pink petals up to 1 mm long. In Canada, Toothcup is at the northern limit of its North American range. Populations at the edge of a species’ range may be genetically distinct.

Distribution

Toothcup is native to North America, Central America, and South America. In North America, it ranges in the east from Massachusetts south to Florida, and west from southern Minnesota, south to Texas and into Mexico. It is found only sparingly in the Midwestern US and Intermountain region, appearing more frequently along the west coast from California, north to south-central British Columbia. It has a disjunct distribution in Canada, known from Ontario and British Columbia.

Habitat

Toothcup is a species of open, seasonally wet areas with natural or artificial water level fluctuation. Its habitat includes riverbanks, ditches, pond margins, sandy to muddy shores, interdunal swales, and occasionally, moist edges of cultivated fields. In south-central Ontario, it grows in moist, shallow bedrock crevices filled with small accumulations of sand, gravel and peat along lake and river shorelines. In southwestern Ontario, it formerly grew in remnant sand prairie within moist old field habitat. In the South Okanagan Valley of British Columbia, Toothcup inhabits moist to wet, sometimes saline, muddy to sandy shorelines of lagoons or ponds, inshore swales, and shallow depressions. In the Kamloops area, it inhabits sandy or silty, shallow depressions and interdunal swales, or muddy silty-sands of exposed channel banks.

Biology

Toothcup is an annual plant associated with periodically flooded areas, and populations may undergo large fluctuations from year to year. It reproduces sexually, producing copious amounts of seed. The large majority of Toothcup seeds are dormant when they mature in autumn, but tend to break dormancy while flooded in late fall or winter.

Population Size and Trends

The total Canadian population of Toothcup was estimated to include at least 6,859 individuals in 2011, when it was known from four subpopulations, including two in Ontario (Great Lakes Plains DU) and two in British Columbia (Southern Mountain DU).

In Ontario, counts from 2011 were low relative to counts from previous years. A total of 1,444 mature individuals was recorded (305 mature individuals from Sheffield - Long Lake / Clare River and 1,139 from Puzzle Lake). The highest count was made in 2004, when 4,325-6,325 mature individuals were counted (2,615-4,615 from Sheffield - Long Lake / Clare River and 1610-1710 from Puzzle Lake).

In British Columbia, between 5,410 and 5,570 individuals were observed in 2011 at two sites in the Kamloops subpopulation. No individuals were observed from the other previously reported Kamloops site at McArthur Island. No individuals were observed at the South Okanagan Valley subpopulation in 2011, but not all sites were visited, including one which held an estimated 12,000 individuals in 2004. The highest single year estimate here was 12,180 individuals in 2004.

Since the previous assessment, no losses of Toothcup subpopulations have been documented in Ontario. Infrequent counts at both subpopulations suggest fluctuations among years, though census data are insufficient for assessment of trends. In British Columbia, although the Kamloops subpopulation is extant, the South Okanagan Valley subpopulation is believed to be declining and several sites are known to have been extirpated historically. The likelihood of natural immigration of Toothcup from outside Canada is extremely low.

Threats and Limiting Factors

The Canadian range of Toothcup is limited by its restricted occurrence to seasonally flooded habitats. In Ontario, shoreline development and recreational activities are the main threats. In British Columbia, invasive plant species pose the greatest threat to extant populations of Toothcup. Habitat loss through development, habitat degradation and livestock, as well as the modification of natural Osoyoos Lake levels, are also threats in British Columbia.

Protection, Status, and Ranks

Toothcup was originally designated by COSEWIC as Endangered in Canada in 1999 and is listed on Schedule 1 of the federal Species at Risk Act. A federal Recovery Strategy has not yet been finalized for Toothcup. COSEWIC assessed the Great Lakes Plains population of Toothcup as Threatened and the Southern Mountain population as Endangered in November 2014. Toothcup is listed as an Endangered Species under the Ontario Endangered Species Act, 2007, receiving species and habitat-level protection. It also receives protection in Puzzle Lake Provincial Park and Mellon Lake Conservation Reserve. There is no specific legal protection for Toothcup in British Columbia. The General Status rank for Toothcup is “At Risk” for Ontario, British Columbia, and Canada.

Technical Summary - Great Lakes Plains Population

Scientific Name:
Rotala ramosior
English Name:
Toothcup (Great Lakes Plains population)
French Name:
Rotala rameux (Population des plaines des Grandes Lacs)
Range of occurrence:
Ontario

Demographic Information

  • Generation time (usually average age of parents in the population; indicate if another method of estimating generation time indicated in the IUCN guidelines (2008) is being used).

    • <1 yr
  • Is there an [observed, inferred, or projected] continuing decline in number of mature individuals?

    Consistent monitoring at subpopulations over years is lacking. Possible loss of one site at the Sheffield – Long Lake / Clare River subpopulation (this would represent a loss of 2,615-4,615 mature individuals).

    • Unknown
  • Estimated percent of continuing decline in total number of mature individuals within [5 years or 2 generations]

    • Unknown
  • [Observed, estimated, inferred, or suspected] percent [reduction or increase] in total number of mature individuals over the last [10 years, or 3 generations].

    • Unknown
  • [Projected or suspected] percent [reduction or increase] in total number of mature individuals over the next [10 years, or 3 generations].

    • Unknown
  • [Observed, estimated, inferred, or suspected] percent [reduction or increase] in total number of mature individuals over any [10 years, or 3 generations] period, over a time period including both the past and the future.

    • Unknown
  • Are the causes of the decline clearly reversible and understood and ceased?

    • N/A
  • Are there extreme fluctuations in number of mature individuals?

    A fluctuation in the order of magnitude of 10 or greater has been observed at the Sheffield – Long Lake / Clare River subpopulation (from a low of 0 to a high of 2,615-4,615).

    • Possibly

Extent and Occupancy Information

  • Estimated extent of occurrence

    EO was estimated as 3.4 km2, but in accordance with COSEWIC guidelines, is set equal to the IAO.

    • 20 km²
  • Index of area of occupancy (IAO)

    (Always report 2x2 grid value).

    • 20 km²
  • Is the total population severely fragmented?

    Nearest population is in New York State, over 500 km to the south.

    • No
  • Number of locations
    See Definitions and Abbreviations on COSEWIC website and IUCN 2010 for more information on this term.

    1. Along Puzzle Lake, 4 locations are defined based on land ownership (3 private parcels, 1 for public land)
    2. Sheffield - Long Lake / Clare River, 3 locations (2 private, 1 public).
    • 7
  • Is there an [observed, inferred, or projected] continuing decline in extent of occurrence?

    • No
  • Is there an [observed, inferred, or projected] continuing decline in index of area of occupancy?

    • Unknown
  • Is there an [observed, inferred, or projected] continuing decline in number of populations?

    • No
  • Is there an [observed, inferred, or projected] continuing decline in number of locations?

    • No
  • Is there an [observed, inferred, or projected] continuing decline in [area, extent and/or quality] of habitat?

    • Yes
  • Are there extreme fluctuations in number of populations?

    • No
  • Are there extreme fluctuations in number of locations?

    • No
  • Are there extreme fluctuations in extent of occurrence?

    • No
  • Are there extreme fluctuations in index of area of occupancy?

    • No

Number of Mature Individuals (in each population)

  • Population (in 2011)

    • Puzzle Lake
      • N Mature Individuals: 1,139
    • Sheffield Long Lake – Clare River
      • N Mature Individuals: 305
    • Total
      • N Mature Individuals: 1,444

Quantitative Analysis

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

    • N/A

Threats (actual or imminent, to populations or habitats)

  1. Shoreline development
  2. Shoreline impacts of recreational activities.
  3. Water level manipulation

Rescue Effect (immigration from outside Canada)

  • Status of outside population(s)?

    • U.S.A.: not currently of conservation concern throughout its core range; of conservation concern in adjacent/nearby northeastern states: New Hampshire (SH), Minnesota (S2), New York (S2), and Michigan (S3).
  • Is immigration known or possible?

    Toothcup is present in adjacent states in New York and Michigan.

    • Possible
  • Would immigrants be adapted to survive in Canada?

    • Unknown but likely
  • Is there sufficient habitat for immigrants in Canada?

    Unoccupied habitat exists in central Ontario on undeveloped shorelines with fluctuating water levels.

    • Yes.
  • Is rescue from outside populations likely?

    Toothcup is rare and declining in the northeastern US / adjacent states.

    • Unlikely

Status History

  • COSEWIC Status History: The species was considered a single unit and designated Endangered in April 1999. Status re-examined and confirmed in May 2000. Split into two populations in November 2014. The Great Lakes Plains population was designated Threatened in November 2014.

Status and Reasons for Designation:

Status:
Threatened
Alpha-numeric code:
B1ab(iii)+2ab(iii)
Reasons for designation:
This annual plant is known from the shores of only two lakes at the southern edge of the Canadian Shield in southeastern Ontario. Year-to-year fluctuations in water levels along the lakeshore impact the abundance of plants. Impacts from development, recreational boating activities, and manipulation of water levels have the potential to reduce the number of individuals.

Applicability of Criteria

Criterion A (Decline in Total Number of Mature Individuals):
Not met. Trend data are insufficient to quantify declines.
Criterion B (Small Distribution Range and Decline or Fluctuation):
Meets Threatened B1ab(iii)+2ab(iii) because EO and IAO are below thresholds, there are 7 inferred locations, and habitat quality is declining.
Criterion C (Small and Declining Number of Mature Individuals):
Not met. No documented declines.
Criterion D (Very Small or Restricted Population):
Not met. Although the IAO is below the threshold, threats from habitat modification are not expected to act over very short timeframes.
Criterion E (Quantitative Analysis):
Not met. No quantitative analysis.

Technical Summary - Southern Mountain Population

Scientific Name:
Rotala ramosior
English Name:
Toothcup (Southern Mountain population)
French Name:
Rotala rameux (Population des montagnes du Sud)
Range of occurrence:
British Columbia

Demographic Information

  • Generation time (usually average age of parents in the population; indicate if another method of estimating generation time indicated in the IUCN guidelines (2008) is being used).

    • <1 yr
  • Is there an [observed, inferred, or projected] continuing decline in number of mature individuals?

    Although consistent monitoring at subpopulations over years is lacking, two of the South Okanagan Valley sites may be lost or will be lost because of rapid invasion by introduced grasses.

    • Yes
  • Estimated percent of continuing decline in total number of mature individuals within [5 years or 2 generations]

    • Unknown
  • [Observed, estimated, inferred, or suspected] percent [reduction or increase] in total number of mature individuals over the last [10 years, or 3 generations].

    • Unknown
  • [Projected or suspected] percent [reduction or increase] in total number of mature individuals over the next [10 years, or 3 generations].

    • Unknown
  • [Observed, estimated, inferred, or suspected] percent [reduction or increase] in total number of mature individuals over any [10 years, or 3 generations] period, over a time period including both the past and the future.

    • Unknown
  • Are the causes of the decline clearly reversible and understood and ceased?

    • No
  • Are there extreme fluctuations in number of mature individuals?

    A fluctuation in the order of magnitude of 10 or greater has been observed at two of the South Okanagan Valley sites (from a low of 4 to a high of 2250 and from ~600 to ~12,000), but fluctuations do not appear to be synchronous across sites.

    • Yes

Extent and Occupancy Information

  • Estimated extent of occurrence

    EO was estimated as 3.4 km2, but in accordance with COSEWIC guidelines, is set equal to the IAO.

    • 630 - 1080 km²
  • Index of area of occupancy (IAO)

    (Always report 2x2 grid value).

    • 20 – 28 km²
  • Is the total population severely fragmented?

    • No
  • Number of locations
    See Definitions and Abbreviations on COSEWIC website and IUCN 2010 for more information on this

    1. South Okanagan Valley includes 2-4 locations: one at Mica Spit, another on private property. Both threatened by invasive exotic species. A site on the Osoyoos Oxbows though not seen since 1995 may still be extant and a collection labelled "mouth of Inkaneep Creek" has not been relocated.
    2. Kamloops subpopulation considered 3 locations based on land management and ownership. Location defined based on common threat of invasive exotic species.
    • 5-7
  • Is there an [observed, inferred, or projected] continuing decline in extent of occurrence?

    • Possibly
  • Is there an [observed, inferred, or projected] continuing decline in index of area of occupancy?

    Loss of the South Okanagan Valley subpopulation is projected.

    • Possibly
  • Is there an [observed, inferred, or projected] continuing decline in number of populations?

    Loss of the South Okanagan Valley subpopulation is projected

    • Possibly
  • Is there an [observed, inferred, or projected] continuing decline in number of locations?

    Loss of the South Okanagan Valley subpopulation is projected

    • Possibly
  • Is there an [observed, inferred, or projected] continuing decline in [area, extent and/or quality] of habitat?

    • Yes
  • Are there extreme fluctuations in number of populations?

    • No
  • Are there extreme fluctuations in number of locations?

    • No
  • Are there extreme fluctuations in extent of occurrence?

    • No
  • Are there extreme fluctuations in index of area of occupancy?

    • No

Number of Mature Individuals (in each population)

  • Population (in 2011)

    • South Okanagan Valley (excluding Veronica Lake, Osoyoos Oxbows, and Inkaneep Creek, which were not revisited)
      • N Mature Individuals: 0
    • Kamloops
      • N Mature Individuals: 5,415 – 5,575
    • Total
      • N Mature Individuals: 5,415 – 5,575

Quantitative Analysis

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

    • N/A

Threats (actual or imminent, to populations or habitats)

  1. Invasive Species
  2. Habitat loss and development
  3. Altered flood dynamics

Rescue Effect (immigration from outside Canada)

  • Status of outside population(s)?

    • U.S.A.: not currently of conservation concern throughout its core range; of conservation concern in its northwestern range limits in Montana, Oregon and Washington
  • Is immigration known or possible?

    Toothcup is present in adjacent Washington State.

    • Possible
  • Would immigrants be adapted to survive in Canada?

    • Unknown but likely
  • Is there sufficient habitat for immigrants in Canada?

    Suitable unoccupied habitat also exists in the Kamloops and Thompson River areas of British Columbia.

    • Possibly
  • Is rescue from outside populations likely?

    Toothcup is rare or absent in adjacent or nearby U.S. states.

    • Unlikely

Status History

  • COSEWIC: The species was considered a single unit and designated Endangered in April 1999. Status re-examined and confirmed in May 2000. Split into two populations in November 2014. The Southern Mountain population was designated Endangered in November 2014.

Status and Reasons for Designation:

Status:
Endangered
Alpha-numeric code:
B1ab(iii)+2ab(iii)
Reasons for designation:
This annual plant is known from just two local subpopulations in the Southern Interior of British Columbia. Some locations have been lost as a result of shoreline development; at present, this species is limited by the availability of suitable seasonally wet sites, and threatened by invasive exotic plant species.

Applicability of Criteria

Criterion A (Decline in Total Number of Mature Individuals):
Not met. Trend data are insufficient to quantify declines.
Criterion B (Small Distribution Range and Decline or Fluctuation):
Meets Endangered B1ab(iii)+2ab (iii) because EO and IAO are below thresholds, and there are 5-7 locations, and declines in habitat quality are observed (iii).
Criterion C (Small and Declining Number of Mature Individuals):
Not met. Close to meeting Threatened, but no documented declines (because of inconsistent surveys and fluctuations).
Criterion D (Very Small or Restricted Population):
Not met. Although the IAO is below the threshold, the key threat (invasive exotic species) is not thought to have the potential to act over a very short timeframe.
Criterion E (Quantitative Analysis):
Not met. No quantitative analysis.

Preface

Since the 2002 assessment of the Toothcup, declines at one British Columbia subpopulation have been documented, and habitat quality continues to deteriorate due to shoreline disturbance, change in flood dynamics, and loss of habitat from invasive species.

This report reflects field survey work conducted in 2011 in Ontario and British Columbia, and ongoing monitoring by Ontario Ministry of Natural Resources staff since 2000. Two designatable units (DUs) are described: the Great Lakes Plains DU (Ontario) and the Southern Mountain DU (British Columbia). The division is based on the discreteness of the eastern and western populations and their lack of biotic or abiotic interactions.

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 (2014)

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)
(Note: Formerly described as “Vulnerable” from 1990 to 1999, or “Rare” prior to 1990.)
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)
(Note: Formerly described as “Not In Any Category”, or “No Designation Required.”)
A wildlife species that has been evaluated and found to be not at risk of extinction given the current circumstances.
Data Deficient (DD)
(Note: 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.)
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.

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

Wildlife Species Description and Significance

Name and Classification

Scientific Name: Rotala ramosior (L.) Koehne in Martius, [Fl. brasiliensis 13(2): 194. 1877]

Synonyms:
Ammannia ramosior L.
Ammannia humilis Michaux
Ammannia catholica Cham. & Schlecht
Ammannia monoflora Blanco, Fl. Filip
Ammannia occidentalis DC
Ammannia dentifera A. Gray
Ammannia ramosa Hill
Boykinia humilis (Michx.) Raf.
Peplis occidentalis Sprengel
Rotala catholica (Cham. & Schltdl.) Leeuwen
Rotala dentifera (A. Gray) Koehne
Rotala ramosior var. dentifera (A. Gray) Lundell
Rotala ramosior var. interior Fernald & Griscom

English Common Name: Toothcup, Toothcup Meadow-foam, Branched Toothcup,   Lowland Toothcup, Lowland Rotala, Toothcap, Wheelwort

French Common Name: Rotala rameux

Family: Lythraceae (Loosestrife family)

Major Plant Group: Eudicot flowering plant

Type Specimen: North America, Virginia, Clayton (Gronovius) No. 774 (holotype: BM, see Fernald & Griscom, Rhodora 37: 169. 1935).

Toothcup (Rotala ramosior) is a member of the Lythraceae, which includes terrestrial and aquatic shrubs and trees as well as annual and perennial herbs. Rotala consists of small-flowered annual or perennial herbs of terrestrial, aquatic, or periodically flooded environments. The 49 species of Rotala occur mainlyin the subtropics and tropics, with a few temperate members (Graham et al. 2011). Toothcup is the only native representative of the genus in North America.

Morphological Description

Toothcup is a low, sprawling to erect, simple or branched, terrestrial or semi-aquatic annual, usually 10-25 cm tall with weakly 4-angled stems (Figures 1 & 2). Leaves are in opposite pairs that alternate at right angles along the stem, and flowers are typically solitary with 4 white or pink petals up to 1 mm long. Fruits are globose, up to 4.5 mm in diameter, opening by valves to release numerous dark red to brown seeds, roughly 0.5 mm long (Cook 1979).

In Canada, Toothcup may be mistaken for Scarlet Ammannia (Ammannia robusta) and Marsh Seedbox (Ludwigia palustris). Scarlet Ammannia only grows with Toothcup in British Columbia, while Marsh Seedbox is a common associate in Ontario.

Figure 1. Sprawling Toothcup plant at Puzzle Lake, Ontario.
Sprawling Toothcup plant at Puzzle Lake, Ontario.
Photo: S.R. Brinker © 2011
Long description for Figure 1

Photo of a low and sprawling Toothcup stem. The leaves are borne in opposite pairs that alternate at right angles along the stem. The fruits are red and globose.

Figure 2. Patch of Toothcup plants from Mica Spit area.
Patch of Toothcup plants from Mica Spit area
Photo: C. Björk © 2005
Long description for Figure 2

Photo of a patch of Toothcup plants, showing low, sprawling to erect, simple or branched, stems. Leaves are in opposite pairs that alternate at right angles along the stem, and flowers are typically solitary with four white or pink petals. Fruits are globose.

Population Spatial Structure and Variability

Fernald and Griscom (1935) described two varieties of Rotala ramosior based on geographic distribution and morphological variation. Current treatments of Rotala do not recognize infraspecific taxa(e.g., Godfrey and Wooten 1981; Voss 1985; Gleason and Cronquist 1991; Kartesz 1994; Crow and Hellquist 2000; Michigan Flora Online 2011).

The genetic structure and morphological variability of the Canadian Toothcup population have not been studied. Subpopulations are widely disjunct, occurring in Ontario and British Columbia, and occupy different ecozones. There are no known morphological or genetic differences that distinguish the populations in Ontario and British Columbia.

Designatable Units

Two designatable units (DUs) for Toothcup are described in this report: the Great Lakes Plains designatable unit (Ontario) and the Southern Mountain designatable unit (British Columbia). The Great Lakes Plains DU captures the extirpated Rotala Field subpopulation in Norfolk County as well as the Puzzle Lake and Sheffield – Long Lake / Clare River subpopulations even though they technically lie in the Boreal Ecozone. Because of their proximity to the Great Lakes Plains Ecozone and because Toothcup is not a boreal species, this subpopulation has been included in the Great Lakes Plains DU.  The two proposed DUs (Figure 3) are discrete based on the large, natural disjunction that separates populations in Ontario and British Columbia such that movement of individuals between regions is not likely. This disjunction could drive the formation of genetically distinct populations, and the loss of either unit would significantly alter the Canadian range and extent of occurrence. The ecological settings of subpopulations in the two DUs are notably distinct.

Figure 3. North American distribution of Toothcup with COSEWIC National Ecological Areas. County-level US distribution based on BONAP (2011).
North American distribution of Toothcup
Long description for Figure 3

Map of the North American distribution of the Toothcup. The species ranges widely from Massachusetts west through southern Ontario and Minnesota, and south to Florida, Arkansas, Texas, and Mexico. It is rare in the Intermountain and Rocky Mountain regions, increasing in frequency along the west coast from central California north to southern British Columbia. COSEWIC National Ecological Areas are shown on the Canadian portion of the map.

Special Significance

Toothcup subpopulations in Canada are at the northern limit of the species’ North American range. A number of other plant species of conservation concern found in southern Ontario and British Columbia share similar patterns of distribution and may represent relictual, more southerly populations of a once more continuous distribution (Argus and White 1977; Straley et al. 1985; Argus 1992; Brownell et al. 1996). Populations at the edge of a species range may be genetically distinct and, thus, may be especially important for the future adaptive potential of the species (Lesica and Allendorf 1995).

The genus Rotala is popular among pond and aquarium enthusiasts. Most commercially available and commonly grown species are from tropical Asia and India, but Toothcup is occasionally sought after and propagated.

No Aboriginal traditional knowledge sources for Toothcup have been found.

Distribution

Global Range

Toothcup ranges widely in North America (Figure 3), from Massachusetts west through southern Ontario and Minnesota, south to Florida, Arkansas, Texas, and Mexico. It is rare in the Intermountain and Rocky Mountain regions, increasing in frequency along the west coast from central California north to southern British Columbia. Toothcup also occurs in portions of Central and South America, although its full range in these regions is poorly known.

Canadian Range

Toothcup has a restricted and disjunct distribution in Canada, representing less than one percent of the species’ global range. It is presently known from south-central Ontario and south-central British Columbia.

In Ontario (Figure 4), Toothcup is restricted to shoreline habitat on Puzzle Lake and Sheffield – Long Lake (an enlargement of the Salmon River) and adjoining Clare River. These water bodies are situated along the southern edge of the Canadian Shield in the county of Lennox and Addington. Plants in Ontario are disjunct from the nearest population in New York State by almost 500 km (Brownell et al. 1996). Toothcup was formerly present in two sandy fields near Walsh Station in Norfolk County (Sutherland 1987), roughly 350 km southwest of the southern Shield subpopulations. Both Norfolk County sites were ploughed to make way for cropland by 1987.

Figure 4. Extant locations of Toothcup in Ontario.

Numbered water bodies referred to in the text are: 1. Clare River; 2. Sheffield - Long Lake; 3. Puzzle Lake. Solid circles represent subpopulations documented in 2011; white circles represent previously documented subpopulations not observed in 2011.

Extant locations of Toothcup in Ontario.
Long description for Figure 4

Map showing Ontario localities where the Toothcup was observed in 2011 and localities where it was previously observed but not found in 2011. The species is restricted to shoreline habitat on Puzzle Lake and Sheffield - Long Lake (an enlargement of the Salmon River) and adjoining Claire River. These water bodies are situated along the southern edge of the Canadian Shield in the county of Lennox and Addington.

In British Columbia (Figure 5), Toothcup is known from sites along and north of Osoyoos Lake in the extreme southern part of the Okanagan Valley, and along the eastern end of Kamloops Lake in the Thompson River valley. These two subpopulations are about 180 km apart. Plants at Osoyoos Lake are disjunct from the nearest U.S. population in central Washington State by about 200 km.

Figure 5. Locations of Toothcup in British Columbia.
Locations of Toothcup in British Columbia.
Long description for Figure 5

Map showing British Columbia localities where the Toothcup has been documented. These occur along and north of Osoyoos Lake in the extreme southern part of the Okanagan Valley, and along the eastern end of Kamloops Lake in the Thompson River valley.

Extent of Occurrence and Area of Occupancy

The total extent of occurrence (EO) of Toothcup in Canada is approximately 285,884 km². If calculated for each designatable unit (DU), the EO for the Great Lakes Plains DU (Ontario) is 3.4 km² and 630 - 1080 km² for the Southern Mountain DU (British Columbia). The index of area of occupancy, as determined by a 2x2 km grid overlay, is equivalent to 40 km² in Canada (20 km² in Ontario and 20 - 28 km² in British Columbia).

Delimitation of Subpopulations

COSEWIC separates subpopulations as geographically or otherwise distinct groups between which there is little demographic or genetic exchange (COSEWIC 2012). Because rates of genetic exchange are unknown for Toothcup, subpopulations are defined in this report using NatureServe (2004) Guidelines, under which occurrences meeting one of the following conditions are grouped into a single subpopulation: 1) occurrences separated by less than 1 km, 2) occurrences separated by 1 to 3 km with no break in suitable habitat between them exceeding 1 km, 3) occurrences separated by 3 to 10 km but connected by linear water flow with no break in suitable habitat between them exceeding 3 km. Thus there are four extant subpopulations known to occur in Canada: 1) Puzzle Lake, 2) Sheffield - Long Lake / Clare River, 3) South Okanagan Valley, and 4) Kamloops. The historical Rotala Field subpopulation from Norfolk County is believed extirpated through conversion of habitat to row crops. The historical subpopulations of Hayes Point and Osoyoos townsite are considered extirpated and the status of subpopulations at North Osoyoos Oxbows and the mouth of the Inkaneep River remain undetermined.

Search Effort

Ontario

Toothcup was first discovered in Ontario in 1984 by D. A. Sutherland and M.J. Oldham during a natural areas inventory of the Regional Municipality of Haldimand and Norfolk Counties (Gartshore et al. 1987). Two sites were found adjacent to one another, with plants present two years apart, though both sites were subsequently destroyed through conversion of the land to row crops. These sites have not been observed since 1987 despite occasional visits by Ministry of Natural Resources (MNR) staff and local naturalists. A scan of the fields and roadside ditches in 2011 did not produce any observations and the fields were still under cultivation.

Two additional Ontario subpopulations were found in 1994 along adjacent lakes in the County of Lennox and Addington during a detailed life science inventory of the Puzzle Lake Area of Natural and Scientific Interest (ANSI) (Brownell 1997). Casual monitoring at both lakes since then involving shoreline surveys from a canoe by C. Bonta, L. Viet, and T. Norris have led to the discovery of additional sites associated with these subpopulations. One was found on Puzzle Lake in 2000 (Veit 2000), five in 2004 (Bonta 2004), four in 2008 (Bonta 2008), and three in 2011 as part of fieldwork associated with the update status report. An additional site was found at Sheffield - Long Lake / Clare River in 2004. Elsewhere in the area, portions of Lost Lake, Gull Lake, and Fifth Depot Lake were searched in 2004 but Toothcup was not observed. Additional habitat was searched on Norway and Bear Lake by Ontario Parks staff and little suitable shoreline was identified (Brdar pers. comm. 2011).

Efforts to find Toothcup in Ontario in 2011 are summarized in Table 1. A total of approximately 47 km of shoreline was searched over 9 days incorporating roughly 115 person-hours. Surveys for Toothcup involved scanning shorelines of water bodies for exposed sand and mud from a boat, as well as helicopter-based surveys conducted as part of other fieldwork. This included landing at remote sites, and scanning moist ditches and depressions along roadsides. When suitable habitat was identified, an intuitive meandering search pattern was used to cover appropriate habitat to locate and count all mature individuals.

Table 1. Summary of 2011 Toothcup search effort in Ontario.
Survey Date Site Surveyors Person- Hours Approximate Area Surveyed Outcome
30/08/2011 Puzzle Lake S. Brinker, C. Jones 15 9 km of shore Successful
01/09/2011 Sheffield Long Lake / Clare River S. Brinker, C. Jones 12 5 km of shore Successful
29/09/2011 Sheffield Long Lake, Salmon River S. Brinker, M. Oldham, C. Jones 15 8 km of shore Successful
06/10/2011 Puzzle Lake S. Brinker 2 100 m of shore Successful
23/08/2011 Mellon Lake S. Brinker, T. Norris 15 10 km of shore Unsuccessful
30/08/2011 Gull Lake S. Brinker, C. Jones 0.5 100 m of shore Unsuccessful
07/09/2011 Rotala Field S. Brinker, C. Jones 0.5 50 m of ditch Unsuccessful
12/09/2011 Puzzle Lake Provincial Park wetlands S. Brinker, W. Bakowsky, M. Oldham, C. Jones, R. Craig 20 1 km of shore Unsuccessful
13/09/2011 Kaladar area Crown Land blocks S. Brinker, M. Oldham, M. McMurtry, T. Taylor, C. Bonta 20 1 km of shore Unsuccessful
05/10/2011 Kennebec Lake S. Brinker, M. Oldham 7.5 7 km of shore Unsuccessful
05/10/2011 5th Depot Lake S. Brinker, M. Oldham 7.5 6 km of shore Unsuccessful
Totals - - ~ 115 hrs ~ 47 km Unsuccessful

While no other specific efforts have been made to search for Toothcup in Ontario, there has been a fairly substantial body of fieldwork conducted over the last 40 years by competent field biologists and botanists within its range. Caution is necessary when interpreting negative survey results, however. Even with targeted surveys, Toothcup can be easily overlooked, especially in areas with small populations or during high water years. Also, timing is critical, as surveys outside the normal period of detection (late summer/early fall) could lead to false absences.  

In the Puzzle Lake area, most large and accessible lakes have been surveyed, though not over multiple years.  However, the region still supports areas of suitable habitat that have not been searched by botanists, largely due to inaccessibility and private property limitations. Priorities for additional targeted searches include areas of low nutrient, gently sloping shoreline and naturally fluctuating water levels along the southern edge of the Canadian Shield in eastern Ontario, especially those east of Puzzle Lake to Kingston. In contrast, few moist, open, acidic sandy areas remain in Norfolk County or elsewhere in southern Ontario off the Canadian Shield, and the best remaining examples of these have been well botanized. The likelihood of rediscovering Toothcup in Norfolk County is low, though plausible with the continued existence of a few remnant moist, sandy meadows in the St. Williams – Turkey Point – Walsh area. Most of these occur on private land and are not accessible, however.

British Columbia

South Okanagan Valley: previous searches--The first documented Canadian record of Toothcup was J.W. Eastham’s 1939 collection from an unspecified locality alongside Osoyoos Lake in British Columbia (UBC V25712). J.A. Calder and D.B. Savile made another early collection (UBC V84759) at Hayne’s Point (just south of Osoyoos) in 1953. In 1977, O. Ceska and P.D. Warrington found a third occurrence for Toothcup in the South Okanagan Valley on the shore of a ponded area along Osoyoos Lake in the town of Osoyoos.

The Mica Spit occurrence, on Osoyoos Indian Band property, was discovered by A. Ceska in 1980. G.W. Douglas and numerous co-workers investigated this occurrence starting in 1994 (Douglas 1994) and continuing to 2004 with the assistance of Osoyoos Indian Band members. These searches resulted in the discovery of at least four sites for Toothcup on sandy or muddy soils most often along the edges of inshore lagoons. Two of the original sites for Toothcup were destroyed during this time, one by ATV use and the other by wave action (Douglas and Oldham 2002). Further investigations by McIntosh and Björk between 2005 and 2007 confirmed at least four sites of Toothcup in the Mica Spit area. One site was located in 2005 and three more sites in 2007 (Björk pers. comm. 2012). One of the 2007 sites was adjacent to the larger lagoon at Mica Spit and two were found in swales on private property north of Mica Spit. The landowners have requested that locality and population data not be made available for this report (McIntosh pers. comm. 2012).

A collection of Toothcup was made by Lomer in 1995 just north of Osoyoos Lake in the Osoyoos oxbow area (BCCDC 2012). This site was not reported in Douglas and Oldham (2002) nor by the National Toothcup Recovery Team (2008).

The historical sites for Toothcup at Haynes Point (Calder’s collection) and in the Town of Osoyoos (O. Ceska and Warrington’s collection) were surveyed for Toothcup and other rare plants by boat and walking surveys in 2009 (McIntosh 2010). All potential habitats for at-risk shoreline plants along the Canadian Osoyoos Lake shorelines, excluding Osoyoos Indian Band property, were surveyed that year. Toothcup was not observed along the lake during the survey. Extensive searches for rare plants were also completed by various botanists at Hayne’s Point in 1991, 1994, 1995, 1997, 1999, and 2002 and Toothcup was not observed (BCCDC 2012). Toothcup is considered extirpated at both the Hayne’s Point and Osoyoos localities (BCCDC 2012). Heavy modifications of the shoreline probably destroyed the Hayne’s Point site. Extensive shoreline development destroyed the pond edges and all potential Toothcup habitat at the Town of Osoyoos site (A. and O. Ceska pers. comm. 2012).

Kamloops area: previous searches--The first collection of Toothcup from the Kamloops area was made by A.C. Budd in 1948. The precise locality for this collection is unknown as collection data are vague. It was collected west of one of the two Agriculture Canada stations that were operating at the time, but at which station is not clear. One station was located on each side of Kamloops Lake (BCCDC 2012). Therefore, the collection was made either in the Mission Flats area on the south side of the river or on the north side towards Tranquille. When Toothcup was observed in Mission Flats in 2011, it had not been observed in either of these areas since 1948. In 1980, O. Ceska and A. Ceska discovered a new subpopulation of Toothcup for the Kamloops area on the east side of McArthur Island on the north side of Kamloops Lake (BCCDC 2012).

2011 Searches--Efforts to locate Toothcup in British Columbia in 2011 are summarized in Table 2. Almost 14 km of shoreline and ponded inland sites were searched over 13 days incorporating approximately 88 person-hours. Most surveys were completed on foot, focusing on open soil along shorelines or inshore depressions, pond edges, and swales. An intuitive meandering search pattern was used to investigate appropriate habitats. A canoe was used to access Rabbit Island in Kamloops. Two of the known sites (McArthur Island near Kamloops and in the oxbows north of Osoyoos Lake) were visited twice because water drawdown was late at both sites.

Table 2. Summary of 2011 Toothcup search effort in British Columbia.
Survey Date Site Surveyors Person- Hours Approximate Area Surveyed Outcome
17/09/2011 McArthur and Rabbit Islands T. McIntosh, Jamie Fenneman, Justine McCulloch, Mandy Ross 32 3 km of shore and inland ponded sites Successful
27/09/2011 Mission Flats T. McIntosh, S. Joya 8 2 km of shore and inland ponded sites Successful
30/09/2011 McArthur Island and Mission Flats T. McIntosh, S. Joya 6 800 m of shore and inland ponded sites Successful
17/08/2011 Sun Oka Beach Provincial Park T. McIntosh 1.5 ~120 m of shoreline and inshore habitats Unsuccessful
31/08/2011 McArthur Island and the Tranquille Wildlife Management Area T. McIntosh, J. McCulloch 12 2 km of shore and inland ponded sites Unsuccessful
02/09/2011 Osoyoos Oxbows T. McIntosh 4 800 m of shore and inland ponded sites Unsuccessful
08/09/2011 Osoyoos Oxbows T. McIntosh 2.5 800 m of shore and inland ponded sites Unsuccessful
09/09/2011 Osoyoos Oxbows T. McIntosh 5.5 800 m of shore and inland ponded sites Unsuccessful
09/09/2011 Pyramid Provincial Park T. McIntosh 1 ~100 m of shoreline habitats Unsuccessful
09/09/2011 SW Okanagan Falls T. McIntosh 1 ~80 m of shoreline habitats Unsuccessful
10/09/2011 Osoyoos Oxbows T. McIntosh 2.5 250 m of shore and inland ponded sites Unsuccessful
14/09/2011 Osoyoos Oxbows T. McIntosh 4 300 m of shore and inland ponded sites Unsuccessful
22/09/2011 Mica Spit T. McIntosh, A. Baptiste 2 800 m of inland ponded sites Unsuccessful
22/10/2011 Osoyoos Oxbows T. McIntosh 1.5 600 m of inland ponded sites Unsuccessful
23/09/2011 Osoyoos Oxbows T. McIntosh 1.5 600 m of shore and inland ponded sites Unsuccessful
29/09/2011 N shore of Thompson River and Tk’emlups Marsh T. McIntosh, S. Joya 3 900 m of shore Unsuccessful
Total - - ~ 88 hrs ~ 13.9 km Unsuccessful

South Okanagan Valley 2011: Toothcup was not observed at any of the previously reported sites and no new subpopulations were discovered.

Kamloops area 2011: Although Toothcup was not observed at the McArthur Island site, six new sites were discovered, five along Mission Flats and a sixth on Rabbit Island.

Little suitable habitat for Toothcup remains in the South Okanagan Valley as a result development and invasion by aggressive exotic plants, mainly Reed Canary Grass (Phalaris arundinacea). The likelihood of rediscovering Toothcup in this area is low. In contrast, the Kamloops Lake and Thompson River areas north and east of Kamloops still support large areas of suitable habitat that have not been evaluated by botanists in part due to inaccessibility, but also due to lack of both broad inventory and targeted search efforts. However, some suitable habitat in these areas has received coverage (especially in 2011), but not over multiple years. There is potential for additional sites and subpopulations to be discovered in the Kamloops area.

Habitat

Habitat Requirements

There are no detailed studies of Toothcup habitat, though many descriptive references are available and they consistently indicate Toothcup requires open, seasonally wet areas with natural or artificial water level fluctuation. Over its range, Toothcup habitat is described as riverbanks, ditches, pond margins, sandy to mucky shores, interdunal swales, and occasionally in moist edges of cultivated fields. It is also a relatively widespread weed in rice fields in the United States and elsewhere (Cook 1979). Toothcup is intolerant of shade, and plants tend to be reduced both in vigor and density when light levels are reduced by competing vegetation (Mattrick 2001; Brinker pers. obs.).

In New York, Toothcup is associated mainly with coastal plain pond shores (New York Natural Heritage Program 2012). In Michigan, Toothcup has a high fidelity to coastal plain marsh and lake plain wet-mesic prairie (Michigan Natural Features Inventory 2012). In New England, Toothcup is limited to pond, lake, and reservoir shorelines following natural or anthropogenic water drawdowns, although it is apparently absent from coastal plain ponds there (Mattrick 2001). Typical habitat in Minnesota is sandy shores of small shallow lakes in a savannah landscape (Minnesota Department of Natural Resources 2012). In Washington State, Toothcup is limited to riparian wetlands where it grows below the high water level in a community of small emergent annual plants (Washington Department of Natural Resources 2012).

Ontario

The central Ontario subpopulations occur in the Georgian Bay Fringe, a broad Precambrian bedrock-controlled belt covering about 2,000 km² bordering Georgian Bay, running east through the Kawartha Lakes region as far as Frontenac County. Soils are typically thin, stony, sandy and generally acidic (Chapman and Putnam 1984). Toothcup is limited to rocky shorelines with naturally fluctuating water levels (Figures 6 and 7). Annual water drawdowns are common most summers as precipitation deficit values are high, being just beyond the immediate Great Lakes-effect precipitation zone, and coupled with high summer temperatures and low water-retaining capacities of the shallow substrates (Baldwin et al. 2000). Shorelines where Toothcup is found here consist of exposed bedrock with shallow crevices and faults containing small accumulations of sand, gravel and peat.

Figure 6. Oblique view of exposed rocky shoreline habitat with shallow linear crevices where Toothcup grows at Puzzle Lake, Ontario (at site P10), Aug. 30, 2011 (S. Brinker).
Oblique view of exposed rocky shoreline habitat
Photo: S. Brinker ©
Long description for Figure 6

Photo of Toothcup habitat at Puzzle Lake, Ontario. Shorelines where Toothcup is found in Ontario consist of exposed bedrock with shallow crevices and faults containing small accumulations of sand, gravel and peat.

Figure 7. Exposed rocky shoreline habitat with shallow crevices at Sheffield Long Lake / Clare River, Ontario, Sept. 01, 2011 (S. Brinker).
Exposed rocky shoreline habitat
Photo: S. Brinker ©
Long description for Figure 7

Photo of Toothcup habitat at Sheffield Long Lake - Claire River, Ontario. Shorelines where Toothcup is found in Ontario consist of exposed bedrock with shallow crevices and faults containing small accumulations of sand, gravel and peat.

The southwestern Ontario subpopulation occurred on the Norfolk Sandplain, a large wedge-shaped plain covering much of Norfolk County and portions of Brant, Haldimand, Oxford, and Elgin Counties on the north shore of Lake Erie, covering an area of over 1,900 km² (Chapman and Putnam 1984). Habitat information for the former Norfolk County subpopulation was described as remnant sand prairie within a moist old field (D. Sutherland pers. comm. 2011). Substrates were wet-mesic to mesic sands of the Normandale Series, which tend to be strongly acidic to neutral with groundwater often at or near the surface during the early part of the growing season (Presant and Acton 1984). Plants were growing in periodically inundated wet depressions (D. Sutherland pers. comm. 2011).

British Columbia

In British Columbia, Toothcup subpopulations are found in the bottoms of two major valley systems within the Okanagan Highlands Ecoregion, one of the warmest and driest regions in Canada. The region lies within the rain shadow of the Cascade Mountains. The climate is characterized by very warm to hot, dry summers and moderately cool winters with relatively little snowfall. The valley bottoms are characterized by a vegetation matrix of grasslands, shrub-steppe, and riparian vegetation adjacent to the waterways.

Toothcup depends on water-level fluctuations for the creation and maintenance of suitable habitat. Normally, high water levels along the valley bottoms from spring snow melt and winter-spring rainfall submerge the habitats of Toothcup. As water levels recede into the summer, soils in these habitats are exposed and Toothcup seeds germinate. This cycle has been mostly maintained along the Thompson River near Kamloops, except at the McArthur Island site where the channels have been isolated by bridges and connected by culverts, However, the cycle has been highly modified in the south Okanagan Valley by the building of a dam at the base of Osoyoos Lake and by the construction of the Okanagan River diversion/flood control channel north of the lake (International Osoyoos Lake Board of Control 2012, Department of Ecology, State of Washington 2013).

In the South Okanagan Valley, Toothcup inhabits moist to wet, sometimes saline, muddy to sandy shorelines of lagoons or ponds (BCCDC 2012, National Toothcup Recovery Team 2008). Further details include on sand alongside river channels, often in semi-shaded sites. Invasive grasses, in particular Reed Canary Grass, have invaded some sites.

In Mission Flats and on Rabbit Island east of Kamloops, Toothcup inhabits sandy or silty, shallow depressions and interdunal swales (Figure 8). Most of the open habitats at these sites are covered with dense mats of invasive grasses, mainly Quackgrass (Elymus repens) and Smooth Brome (Bromus inermis). However, a number of lightly vegetated swales and depressions are present in areas where sustained water levels probably restrict high grass cover. Some of the habitats where Toothcup are found are kept open by human use, mainly walking or ATV trails but also small excavations and bush clearing (Figure 8).

On McArthur Island, Toothcup grows on muddy silty-sands of exposed banks along a channel (BCCDC 2012, National Toothcup Recovery Team 2008). This habitat is semi-shaded mainly by Narrow-leaf Willow (Salix exigua var. exigua).

Figure 8. Habitat for Toothcup at Mission Flats showing trail maintained by human use, British Columbia, Sept. 29, 2011 (T.M. McIntosh).
Habitat for Toothcup at Mission Flats showing trail
Long description for Figure 8

Photo of Toothcup habitat at Mission Flats, British Columbia. Here, the Toothcup inhabits sandy or silty, shallow depressions and interdunal swales. Most of the open habitats at these sites are covered with dense mats of invasive grasses, mainly Quackgrass (Elymus repens) and Smooth Brome (Bromus inermis).

Habitat Trends

Ontario

Compared to other areas of central Ontario, the southern Shield portion of Lennox and Addington County has resisted the infiltration of intensive forestry, quarrying, and mining activities, although the majority of the area was logged by the turn of the century (Chapman and Putnam 1984). However, over the past 80 years or so, shoreline habitat on most of the larger, accessible lakes in the county has been impacted to some degree by shoreline development or impoundments, which control water level for downstream flood abatement or navigation (e.g., Trent-Severn Waterway, Rideau Canal Waterway).

Complete conversion of occupied habitat to cropland caused the extirpation of the Norfolk County subpopulation.

British Columbia

Following European settlement, there was a great deal of loss of Toothcup habitat in British Columbia. Initially, the majority of this habitat was lost through urban growth, with some sites lost to agricultural activities. More recently, large areas of suitable habitat have been lost or degraded due to invasive exotic grasses, in particular Quackgrass, Smooth Brome, and Reed Canary Grass, but also, in a few cases, Common Cattail (Typha latifolia) and Hard-stemmed Bulrush (Schoenoplectus pungens).

In the south Okanagan Valley, with the exception of some protected ponds along the east side of Osoyoos Lake on Osoyoos Indian Band property and in some portions of the oxbows north of Osoyoos Lake, inshore habitats favoured by Toothcup have been heavily altered or destroyed. Figure 9, upper panel, shows the early town of Osoyoos (from the southeast), probably from around 1925. A number of foreshore ponds can be observed. Figure 9, lower panel, shows the same area in 2002. The images show that the build-up of the City of Osoyoos has permanently altered the two large ponds. Pond B on Fig. 9 is the site where O. Ceska and P.D. Warrington discovered Toothcup in 1977 (this subpopulation has been extirpated).

Toothcup habitats have also been altered and possibly destroyed following the building of a dam in 1927, rebuilt in 1988, at the base of Osoyoos Lake in Washington State. Based on agricultural and other water needs in Washington, Osoyoos Lake water levels have been controlled by the dam since that time, leading to increased lakeside erosion and unnatural drawdown events (State of Washington Water Research Center 2011). The building of the Okanagan River diversion / flood control channel north of Osoyoos Lake in the 1960s has completely altered the hydrology and flooding regimes of the Osoyoos oxbows, which probably housed considerable habitat for Toothcup. Some oxbows are flooded annually, while others are not.

There has also been a loss of Toothcup habitat in the Kamloops area. Although many of the shoreline habitats along Kamloops Lake and the Thompson River remain, many have been altered and degraded in some places by agricultural practices, recreational activities, and invasive species. Invasive grasses are especially common and cover large areas of formerly exposed sands and silts. The sites where new subpopulations were located in 2011, and which had plants in 2014 appear to have lower densities of Quackgrass than immediately surrounding areas. In one case, the site appears to have been formed by tire tracks, which created a depressed area that remains wet over a greater portion of the growing season. These wetter sites appear to be less favourable for Quackgrass, and more favourable for Toothcup (Ryan, pers. comm. 2014).

Figure 9. A view of Osoyoos and Osoyoos Lake. Upper panel, circa 1925 showing large ponded areas on both sides of the spit, marked as A and B (photographer unknown). Lower panel, 2002, showing development around the ponded areas (T. McIntosh).
A view of Osoyoos and Osoyoos Lake.
Photos: Photographer unknown, © T. McIntosh
Long description for Figure 9

Two photos of Osoyoos and Osoyoos Lake, one taken in about 1925 and the other in 2002. The earlier image shows large ponded areas on both sides of the spit and is annotated to show the site where the Toothcup was discovered in 1977. The later image shows the urban development around the ponded areas. The subpopulation observed in 1977 is now extirpated.

Biology

Scant literature pertains to the biology of Toothcup. The information presented here is summarized largely from Mattrick (2001) and Douglas and Oldham (2002), unless otherwise cited.

Life Cycle and Reproduction

Toothcup is an annual plant associated with periodically flooded areas. Subpopulations and sites within these are dependent on a seed bank and may undergo large fluctuations in the number of mature individuals from year to year. The species has a generation time less than one year. Annual fluctuations in seed germination and growth are likely dependent on the timing and amount of seasonal rainfall and water levels at each site. Flowering times vary across the North American range, from June or July through October; in lower latitudes it likely flowers year round (Cook 1979). Canadian subpopulations usually flower in late July to late August, rarely into October. Toothcup is self-compatible and is most often self-pollinated, and produces copious amounts of seed. Like other annual species, Toothcup is not known to reproduce asexually. Cook (1979) suggests that due to the potentially large amount of selfing within subpopulations, gene flow among subpopulations is likely to be low. Insect pollination has not been reported, although Douglas (1999) suggests that plants are likely visited by skippers and small bees for nectar produced by thickened glands surrounding the base of the ovary.

Physiology and Adaptability

Baskin et al. (2002) studied the germination requirements of Toothcup and Valley Redstem in controlled greenhouse experiments. They found 65-100% of Toothcup seeds to be dormant at maturity in autumn. Seeds broke dormancy while flooded in late fall / winter. The optimal temperature regime for dormancy break in seeds of Toothcup was 20°C (day) and 10°C (night). A much higher percentage of seeds germinated when flooded than non-flooded. It is not clear whether seeds can remain dormant beyond their first winter.

Observations in Ontario suggest Toothcup may prefer slightly acidic soil and water conditions, although in British Columbia it is known to occupy (in some sites at least) slightly saline soil, but detailed soil and water tests have not been completed.

There is evidence that Toothcup grows well in culture. Allen (2006) reared stock from wild populations in Maryland in a controlled aquarium environment and found Toothcup easy to grow under bright lighting.

Dispersal and Migration

Dispersal in Toothcup is through passive movement of seeds, likely involving both abiotic and biotic mechanisms. The small size and weight of Toothcup seeds makes them highly vagile and suitable for water and, potentially, wind dispersal. It is not known whether seeds can float, though fluctuating water levels likely aid in short distance dispersal. The seeds have minute epidermal hairs that allow them to attach to the feet of waterfowl (Graham pers. comm. 2001) and, therefore, could be transported to new sites either on waterfowl or in mud stuck to the feet of waterfowl. The absence of this species in apparently suitable habitats near occupied sites in the Puzzle Lake area suggests that Toothcup normally only disperses over short distances, or else rarely becomes established despite dispersal.

Interspecific Interactions

No symbiotic or parasitic relationships are known. No herbivory has been reported or observed on Toothcup plants. Given its preference for open, recently exposed, moist substrates, Toothcup is likely intolerant of competition, although no studies have shown this.

Population Sizes and Trends

Sampling Effort and Methods

Efforts to monitor subpopulations in Canada have been irregular, occurring as time and conditions have permitted, or incidentally while conducting other survey work. As well, surveys are not always thorough assessments of an entire subpopulation, owing to issues relating to, for example, access, weather, and available resources. Furthermore, previous assessments typically provided estimate ranges of the number of individuals rather than absolute counts, as plants can often be hard to detect and can occur at high densities. Sampling has normally been conducted during peak flowering / fruiting periods between August and September, as was done in some cases in 2011.

Abundance

The current Canadian population estimate of Toothcup consists of 6,859 to 7,019 individuals from four subpopulations, including two in Ontario (Great Lakes Plains DU) and two in British Columbia (Southern Mountain DU). Following the IUCN (2001) guidelines, which state to use the lower estimate for populations that fluctuate, the Canadian population currently sits at 6,859 mature individuals.

Ontario (Great Lakes Plains DU)

In 2011, 1,444 mature individuals were counted from two subpopulations, representing the lowest year count. Searches at Puzzle Lake documented 1,139 individuals from 10 sites (Table 3), and 305 individuals from Sheffield – Long Lake / Clare River from one site.

Table 3. Ontario estimates of Toothcup by survey year. Noteaof Table 3
Subpopulation Site Ownership Year Discovered Survey Results

1994
Survey Results

2000
Survey Results

2004
Survey Results

2008
Survey Results

2011
Puzzle Lake P01 Public 1994 50 5-10 400 400 305
Puzzle Lake P02 Public 1994 - 50 150-200 150 0
Puzzle Lake P15 Public 2011 - - - - 65
Puzzle Lake P16 Public 2011 - - - - 45
Puzzle Lake P05 Private 2000 - 200 0 60 454
Puzzle Lake P06 Private 2004 - - 700 30 12
Puzzle Lake P17 Private 2011 - - - - 3
Puzzle Lake P07 Public 2004 - - 40 75 83
Puzzle Lake P08 Public 2004 - - ~200 ~200 52
Puzzle Lake P09 Public 2004 - - 50-70 60 40
Puzzle Lake P10 Public 2004 - - 70-100 0 80
Puzzle Lake P11 Public 2008 - 200 - 140 -
Puzzle Lake P12 Public 2008 - - - 100 0
Puzzle Lake P13 Public 2008 - - - 300-400 -
Puzzle Lake P14 Public 2008 - - - 25 0
Puzzle Lake Totals - - - 50 455-460 1610-1710 1,540-1,640 1,139
Sheffield-Long Lake/Clare River S01 Public 2004 - - 215 - 0
Sheffield-Long Lake/Clare River S03 Private 1994 33 250-270 1400 - 305
Sheffield-Long Lake/Clare River S04 Private 1994 - - 1000-3000 - 0
Sheffield-Long L./Clare River Totals - - - 33 250-270 2,615-4,615 - 305
Ontario Totals - - - 83 705-730 4,225-6,325 1,540-1,640 1,444

The highest Ontario estimate of any year was between 4,325 and 6,325 mature individuals in 2004. At this time, 1,610-1,710 individuals were counted at Puzzle Lake from 7 sites scattered across 2 km of shoreline, and 2,615 to 4,615 individuals from three sites (one on the east shore and two closely spaced ones 500 m to the west at the mouth of the Clare River). In other years, casual monitoring has resulted in additional sites at Puzzle Lake, but never have all 15 sites been present in one survey year.

British Columbia (Southern Mountain DU)

The highest estimate for the South Okanagan Valley subpopulation was more than 12,180 individuals in 2004. Ten or eleven (unsure because of lack of precise early data from the Mica Spit site) sites have been found along about 11 km of Osoyoos Lake shoreline: one in the oxbow area to the north, eight or nine along the east side of the lake to Osoyoos (mainly in the Mica Spit area), and one at Haynes Point south of Osoyoos. No Toothcup plants were observed in the South Okanagan Valley during searches in 2011 (Table 4).

Table 4. British Columbia estimates for Toothcup by survey year. Notebof Table 4
Subpopulation Site Year Discovered Survey Results (estimates)

1981
Survey Results (estimates)

1991
Survey Results (estimates)

1994
Survey Results (estimates)

1995
Survey Results (estimates)

1996
Survey Results (estimates)

1997
Survey Results (estimates)

1999
Survey Results (estimates)

2002
Survey Results (estimates)

2003
Kamloops Mission Flats 1 2011 - - - - - - - - -
Kamloops Mission Flats 2 2011 - - - - - - - - -
Kamloops Mission Flats 3 2011 - - - - - - - - -
Kamloops Mission Flats 4 2011 - - - - - - - - -
Kamloops Mission Flats 5 2011 - - - - - - - - -
Kamloops McArthur Island 1 1980 1,000 - 0 - 0 0 - 0 -
Kamloops Rabbit Island 1 2011 - - - - - - - - -
Kamloops Totals - - 1,000 - 0 - 0 0 - 0 -
South Okanagan Valley Mica Spit 1 1980 - - 200 – 1,000 2,250 - - >5,000 0 4
South Okanagan Valley North Osoyoos Oxbows 1
(Deadman Lake) (status uncertain)
1995 - - - 4-5 - - - - -
South Okanagan Valley Veronica Lake  (East Osoyoos small lake) Private property 1994 - - ~600 - - - - - -
South Okanagan Valley Haynes Point (extirpated) 1953 - 0 0 0 - 0 0 0 -
South Okanagan Valley Town of Osoyoos (pond) (extirpated) 1977 - - - - - - - - -
South Okanagan Valley Inkaneep Creek
(locality unconfirmed)
1995 - - - - - - - - -
South Okanagan Valley Totals - - - - 800 – 1,600 ~2,255 - - >5000 - 4
Totals - - 1,000 - 800 – 1,600 ~2,255 - - >5000 - 4
Table 4. British Columbia estimates for Toothcup by survey year. (Continued)
Subpopulation Site Year Discovered Survey Results (estimates)

2004
Survey Results (estimates)

2005
Survey Results (estimates)

2009
Survey Results (estimates)

2011
Kamloops Mission Flats 1 2011 - - - 5
Kamloops Mission Flats 2 2011 - - - >5,000
Kamloops Mission Flats 3 2011 - - - 100-200
Kamloops Mission Flats 4 2011 - - - 50-100
Kamloops Mission Flats 5 2011 - - - 10 – 20
Kamloops McArthur Island 1 1980 3 - - 0
Kamloops Rabbit Island 1 2011 - - - >250
Kamloops Totals - - 3 - - >250
South Okanagan Valley Mica Spit 1 1980 160 -180 ~50 0 0
South Okanagan Valley North Osoyoos Oxbows 1
(Deadman Lake) (status uncertain)
1995 - - - 0
South Okanagan Valley Veronica Lake  (East Osoyoos small lake) Private property 1994 ~12,000 - - -
South Okanagan Valley Haynes Point (extirpated) 1953 - - 0 -
South Okanagan Valley Town of Osoyoos (pond) (extirpated) 1977 - - 0 -
South Okanagan Valley Inkaneep Creek
(locality unconfirmed)
1995 - - - -
South Okanagan Valley Totals - - ~12,180 ~100 - 0
Totals - - ~12,180 ~100 - >5,500

For the Kamloops subpopulation, the highest estimate was between 5,415 and 5,575 individuals in 2011. A total of seven sites have been found along about 4.2 km of shoreline (excluding the observation of Budd in 1948, which may or may not be one of the recent discoveries). Five of the sites are on the south shore, one on an island, and one on the north shore. The highest estimate for the previously reported McArthur Island site (not found in 2011) was 1,000 in 1981 (Table 4).

Fluctuations and Trends

Being an annual plant reliant on dynamic flood regimes, Toothcup can undergo large fluctuations from year to year. While long-term trend data are lacking for Canadian subpopulations, there are short-term data that illustrate this.

Ontario (Great Lakes Plains DU)

Counts for Ontario subpopulations are summarized in Table 3. No documented Toothcup losses have occurred at Puzzle Lake or Sheffield Long Lake / Clare River, and both subpopulations lack adequate long-term data to make any meaningful interpretations of trends. Puzzle Lake has been the most consistently monitored subpopulation, having four surveys completed over an eleven year period (2000-2011). No large fluctuations have been observed here, and new sites have been continually found with increased search effort.

Large fluctuations have been observed at Sheffield – Long Lake / Clare River. In 2004, site S04 contained 1,000-3,000 plants, while in 2011 no plants were seen. At site S03, 1,400 plants were observed in 2004 and in 2011 only 305 were counted.

The Norfolk County subpopulation was destroyed when the habitat was converted to row crops in the late 1980s, and is considered extirpated.

British Columbia (Southern Mountain DU)

Counts for BC subpopulations are presented in Table 4. Although the Kamloops subpopulation is extant, the status of the South Okanagan Valley subpopulation is less clear although some sites have been extirpated (Table 4).

Within the South Okanagan Valley subpopulation, two sites, at Hayne’s Point and in the town of Osoyoos, are considered extirpated. Most of the other sites appear to have declined in the past decade and may also be extirpated (fluctuations and trends for the sites on private properties are unknown). The Osoyoos oxbow site was small to begin with (4-5 plants) and may be extirpated given the high degree of invasive plant cover at the site observed in 2011. Open soil was fairly common at this site in 1995 (F. Lomer pers. comm. 2011). The Mica Spit sites have declined, especially over the past eight years, mainly due, probably, to a marked increase in the presence of invasive grasses. Marked fluctuations were noted at some sites on Mica Spit between 1980 and 2004, possibly due to natural climate and drawdown factors as related to seed germination. Douglas and Oldham (2002) noted that between 1994 and 1995 numbers at one site increased from 200 to 250 plants and in another site, increased from 50 to 2,000. Five thousand plants were reported from one site in 1999.

The National Toothcup Recovery Team (2008) stated that ~5,000 plants were observed in the South Okanagan Valley subpopulation in 2006, but this is a reporting error (McIntosh conducted surveys for rare plants in 2006 on the spit and no Toothcup plants were observed, Table 4).

New discoveries in 2011 greatly expanded the number of known occurrences and mature individuals at the Kamloops subpopulation. As a result, the Kamloops subpopulation has more known mature individuals than in the past. However, the McArthur Island site has declined since its discovery in 1981, when 1,000 plants were estimated to be present. Only three plants were observed in 2004, and none were found in 1994, 1996, 1997 and 2002 (BCCDC 2012), and none in 2011 (Table 4). Water levels were unusually high in 2011 and germination may not have occurred. Suitable habitat appears to remain available along the banks at this site.

Rescue Effect

The likelihood of a natural immigration event of Toothcup from outside Canada is extremely low, though possible. Its highly vagile seeds and self-compatibility increase the likelihood of chance medium- to long-range dispersal and establishment, either by birds or perhaps by water or wind from adjacent jurisdictions in New York, Michigan, Ohio, and Washington. Such an event from adjacent US states is increasingly unlikely, however. In the New England States, Toothcup has declined from 26 known occurrences to only 9 (two in Massachusetts, two in Rhode Island, and five in Connecticut) (Mattrick 2001) and the species is threatened in New York State.

Threats and Limiting Factors

The major limiting factor across the Canadian range of Toothcup is its restriction to seasonally flooded, nutrient poor, gently sloping or flat, sandy shorelines of lakes, ponds, and wet depressions. These areas are particularly vulnerable to human-related disturbance, in particular, shoreline development and agricultural activities, degradation by altered flood regimes, and invasion of exotic plants.

Ontario (Great Lakes Plains DU)

Shoreline Disturbance

Shoreline disturbance associated with waterfront development and recreational activities pose the most immediate threat to Toothcup habitat for the Puzzle Lake and Sheffield – Long Lake / Clare River location. Currently, impacts to Toothcup sites appear minor here, as much of the shoreline is too rocky to develop. However, areas with boat launches, docks, boathouses, and patios along shorelines were observed. Such activities don’t appear to have eliminated any sites, though some areas containing plants are quite small and easily lost. In 2011, two boats stored along the north shore at one particular site on Puzzle Lake were directly shading plants. Another site on Puzzle Lake is amidst a dock at a private lodge and some plants were trampled on the adjacent beach. Excessive vehicular and foot traffic was observed at a private boat launch on Sheffield – Long Lake where another site exists and no plants were seen here in 2011. Roughly one third of the shoreline on Puzzle Lake and two thirds on Sheffield Long Lake / Clare River are currently under private ownership, with ongoing and potential long-term impacts for Toothcup.

Campsite development within Puzzle Lake Provincial Park is expected and may slightly reduce the amount of potential suitable habitat, though the presence of any existing occupied Toothcup habitat will be considered in future management decisions regarding campsite development (Brdar pers. comm. 2012).

Water Management

Lake levels have been manipulated on Puzzle Lake in the past to control natural water draw downs, and the remains of a dam exist at the southern end of the lake, though stop logs are no longer present (Bonta 2004). Currently, the remnants of the dam appear to remain unchanged, although beavers occasionally augment it with debris, which landowners have been known to remove (Bonta pers. comm. 2012).

British Columbia (Southern Mountain DU)

Invasive Species

Invasive exotic plant species pose the greatest threat to extant subpopulations of Toothcup in British Columbia. The Osoyoos oxbows subpopulation may have been lost because available habitat is mostly absent due to the dramatic increase of Reed Canary Grass in the area over the past 5-10 years. Since 2006, a few low areas at the Mica Spit site, in particular the largest lagoon, have been invaded by Common Cattail and Hard-stemmed Bulrush, completely covering much of the previously open soil. In Kamloops, invasive grasses, in particular Quackgrass and Smooth Brome, dominate most of the areas of previously suitable habitat on Rabbit Island and in the Mission Flats area. As noted above (see Habitat Trends), recent observations suggest Toothcup may be restricted to small areas that remain wet, and which are unfavourable to Quackgrass (Ryan, pers. comm. 2014).

Residential and Commercial Development

Habitat loss through development and habitat degradation has led to the extirpation of at least two sites near Osoyoos (Haynes Point and in the Town of Osoyoos).

Water Management

The modification of natural water levels of Osoyoos Lake by a dam appears to have destroyed one of the sites in the Mica Spit area (Douglas and Oldham 2002). Wave action and lakeside erosion have increased over the past few years as the water levels have been kept higher than normal for longer periods of time. Higher water levels may also keep the Mica Spit site wetter longer into the summer, which may also affect the site by allowing invasive plants to establish.

Recreational Activities

Recreational boating activities may have also contributed to erosion events alongside Osoyoos Lake (State of Washington Water Research Center 2011).

Agriculture

Livestock are a threat at the Mica Spit site. Although this area was fenced off about a decade ago, the fence is no longer functional and horses and occasionally cattle have free access to the site. Trampling and manure are common across most of the known Toothcup sites.

Protection, Status and Ranks

Legal Protection and Status

Toothcup was first designated as Endangered in Canada in April of 1999 by COSEWIC on the basis of few remaining sites and a limited occurrence across available habitat that is subject to continued threats from development and elevated water levels. Its status was re-examined and confirmed in May of 2000. Following this, Toothcup was listed on Schedule 1 of the federal Species at Risk Act (2002). A proposed federal recovery strategy was posted in August 2014. COSEWIC assessed the Great Lakes Plains population of Toothcup as Threatened and the Southern Mountain population as Endangered in November 2014. Elsewhere in North America, Toothcup has state-level legal status in several U.S. states: it is listed as Endangered in Connecticut, Massachusetts and Rhode Island, Threatened in Minnesota and New York, Sensitive in Washington and Rare in Pennsylvania (United States Department of Agriculture 2012).

Toothcup is not listed under the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES).

Ontario

Toothcup is listed as Endangered in the Ontario Endangered Species Act, 2007 (ESA). Under the ESA, Toothcup receives species-level and habitat-level protection as of June 30, 2013. Toothcup also receives protection in Puzzle Lake Provincial Park and Mellon Lake Conservation Reserve under the Provincial Parks and Conservation Reserves Act (2006).

British Columbia (Southern Mountain DU)

There is no specific provincial legal protection for Toothcup in British Columbia.

Non-Legal Status and Ranks

NatureServe Explorer (2012) provincial and state status ranks (SRanks) are provided in Table 5. Toothcup is not considered of high conservation concern across the core of its range, but is of conservation concern near the edge of its range where populations tend to be small and fragmented.

Table 5. Toothcup Subnational (S) Ranks based on NatureServe Explorer (2012) status designations.
Country Status Jurisdiction
Canada S1 (Critically Imperilled) British Columbia, Ontario
United States SH (Possibly Extirpated) New Hampshire
United States S1 (Critically Imperiled) Arizona, Colorado, Massachusetts, Montana, Rhode Island, Washington
United States S1S2 (Critically Imperiled to Imperiled) Connecticut
United States S2 (Imperiled) Minnesota, New York, Oregon,
United States S3 (Vulnerable) Delaware, Iowa, Michigan, New Jersey, Pennsylvania, West Virginia
United States S3? (Maybe Vulnerable Nebraska
United States S4 (Apparently Secure) Kentucky
United States S4S5 (Apparently Secure to Secure) Maryland
United States S5 (Secure) Mississippi, North Carolina, Virginia
United States SNR (Unranked) Alabama, Arkansas, California, District of Columbia, Florida, Georgia, Idaho, Illinois, Indiana, Kansas, Louisiana, Missouri, Ohio, Oklahoma, South Carolina, South Dakota, Tennessee, Texas, Wisconsin

The General Status for Toothcup in Canada was assessed in 2005 and it was given a rank of “At Risk” in Ontario, British Columbia (on the provincial Red List), and Canada (CESCC 2006).

Habitat Protection and Ownership

Ontario (Great Lakes Plains DU)

Ontario Toothcup subpopulations are on a mix of public and private land. Roughly half of all plants on Puzzle Lake occur within Puzzle Lake Provincial Park, Crown land managed by the provincial government. Ontario Parks staff are aware of the subpopulations and conduct monitoring along with Ministry of Natural Resources field staff. The remaining sites are on private land, and landowners are aware of their presence and are generally interested in the conservation of the species. Plants found on nearby Sheffield – Long Lake / Clare River occur on a mix of public and private land as well. Two of the three sites (consisting of roughly 53% of the total number of mature individuals) are on private land, while the third occurs within the Mellon Lake Conservation Reserve, owned and managed by the provincial government. One of the private sites is found at a boat launch on the east side of the lake and experiences seasonal vehicular traffic.

The extirpated subpopulation in Norfolk County occurred on private land. One of the two sites was recommended as a Significant Site in the Natural Areas Inventory of the Regional Municipality of Haldimand-Norfolk (Gartshore et al. 1987) though was never adopted into the region’s official plan and the site was subsequently destroyed.

British Columbia (Southern Mountain DU)

Toothcup subpopulations in British Columbia are on a mix of public and private land. In the Okanagan Valley, the Osoyoos Oxbows site is in the BC Parks’ South Okanagan Wildlife Management Area, the Mica Spit sites are on Osoyoos Indian Band property, the extirpated Hayne’s Point site is in a Provincial Park, and the other extirpated site is in the Town of Osoyoos. In the Kamloops area, two sites, one at McArthur Island and one at Mission Flats, are in Municipal Parks, and the remaining sites are on private land. 

Acknowledgements

The report writers wish to thank the following for assistance with fieldwork in Ontario: Mike Oldham, Colin Jones, Wasyl Bakowsky, Mike McMurtry, Rob Craig, Tanya Taylor, all with the Natural Heritage Information Centre; Todd Norris, District Ecologist, with the Ontario Ministry of Natural Resources; and Carolyn Bonta, Assistant Park Planner, Ontario Parks. In addition, the authors wish to acknowledge the NHIC, OMNR, and the Canada Ontario Agreement (COA), which supported portions of fieldwork costs.

In British Columbia, the authors extend thanks to the following for fieldwork assistance: Jamie Fenneman, Justine McCulloch, Mandy Ross, and Steve Joya in the Kamloops area, and Sara Bunge, Mark Weston, Kirk Stafford, Gordon Neish, and Greta Westby in the South Okanagan oxbow areas. Ron Hall and Alan Baptiste provided permission and field support on Osoyoos Indian Band property. Marta Donovan (BCCDC) provided documentation and advice. Sherry Linn provided maps and discussed land ownership and various habitats in the oxbow areas north of Osoyoos Lake. Kristin Dangelmaier, the Environmental liaison for Domtar Inc., has given permission for the use of Toothcup data that were reported from their property in the Mission Flats area.

Authorities contacted

Carolyn Bonta, Assistant Park Planner, Ontario Parks

Corina Brdar, Southeast Zone Ecologist, Ontario Parks

Drs. Adolf and Oluna Ceska, Consulting Botanists, Victoria, BC

Frank Lomer, Consulting Botanist, Vancouver, BC

Todd Norris, District Ecologist, Ontario Ministry of Natural Resources

Mary E. Gartshore, Consulting Biologist

Dr. Anton A. (Tony) Reznicek, Curator of Vascular Plants, University of Michigan University Herbarium

Michael Ryan, Research Ecologist, British Columbia, Thompson Okanagan Region, BC Ministry of  Forests, Lands and Natural Resource Operations.

Donald A. Sutherland, Program Zoologist, Ontario Natural Heritage Information Centre

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Sutherland, D.A., pers. comm. 2011. Conversation with Sam Brinker regarding the nature of occupied Toothcup habitat in Norfolk County. Zoologist, Natural Heritage Information Centre, Peterborough, Ontario.

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Biographical summary of report writers

Samuel R. Brinker is a botanist with the Natural Heritage Information Centre, where he assists with maintaining provincial status ranks and rare species occurrences in Ontario. He also conducts botanical inventories throughout the province and occasionally further abroad. He has authored several status reports and status appraisal summaries. Prior to this, Sam received a Bachelor of Environmental Studies (BES) from the University of Waterloo. He has also held a number of positions with the Ontario Ministry of Natural Resources, as well as working as a consulting biologist focusing on botanical inventories, vegetation mapping and species at risk assessments.

Dr. Terry McIntosh is a consulting botanist who specializes in plants, in particular bryophytes, of arid land ecosystems. He is a Taxon Editor (for the bryophyte volumes) and board member of the Flora of North America project. He has authored nine COSEWIC status reports: Columbian Carpet Moss, Banded Cord-moss, Rusty Cord-moss, Silver-hair Moss, Nugget-moss, Alkaline Wing-nerved Moss, Margined Stream-side Moss, Twisted Oak Moss, and Bent Spike-rush. He has also completed seven National Recovery Strategies. Terry has a strong interest in conservation and natural history, and is working closely with the Osoyoos Indian Band in their conservation efforts.

Collections examined

Ontario collections were examined from the Natural Heritage Information Centre Herbarium (NHIC), Peterborough.

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