Recovery Strategy for the Branched Bartonia (Bartonia paniculata ssp. paniculata) in Canada [Proposed]

Species at Risk Act
Recovery Strategy Series
Adopted under Section 44 of SARA

Branched Bartonia

Photo of Branched Bartonia
Photo: © David J. White,

Table of Contents

List of Tables

List of Figures

Document Information

Recovery Strategy for the Branched Bartonia (Bartonia paniculata ssp. paniculata) in Canada [Proposed]

Cover photo of Branched Bartonia

Recommended citation:

Environment and Climate Change Canada. 2016. Recovery Strategy for the Branched Bartonia (Bartonia paniculata ssp. paniculata) in Canada [Proposed]. Species at Risk Act Recovery Strategy Series. Environment and Climate Change Canada, Ottawa. vii + 27 pp.

For copies of the recovery strategy, or for additional information on species at risk, including the Committee on the Status of Endangered Wildlife in Canada (COSEWIC) Status Reports, residence descriptions, action plans, and other related recovery documents, please visit the Species at Risk (SAR) Public Registry.

Cover illustration: © David J. White

Également disponible en français sous le titre
« Programme de rétablissement de la bartonie paniculée (Bartonia paniculata ssp. paniculata) au Canada [Proposition] »

Content (excluding the illustrations) may be used without permission, with appropriate credit to the source.

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The federal, provincial, and territorial government signatories under the Accord for the Protection of Species at Risk (1996) agreed to establish complementary legislation and programs that provide for effective protection of species at risk throughout Canada. Under the Species at Risk Act (S.C. 2002, c.29) (SARA), the federal competent ministers are responsible for the preparation of recovery strategies for listed Extirpated, Endangered, and Threatened species and are required to report on progress within five years after the publication of the final document on the SAR Public Registry.

The Minister of Environment and Climate Change is the competent minister under SARA for the Branched Bartonia and has prepared this strategy, as per section 37 of SARA. To the extent possible, it has been prepared in cooperation with the Province of Ontario (Ministry of Natural Resources and ForestryFootnote1), and any others as per section 39(1) of SARA.

Success in the recovery of this species depends on the commitment and cooperation of many different constituencies that will be involved in implementing the directions set out in this strategy and will not be achieved by Environment and Climate Change Canada, or any other jurisdiction alone. All Canadians are invited to join in supporting and implementing this strategy for the benefit of the Branched Bartonia and Canadian society as a whole.

This recovery strategy will be followed by one or more action plans that will provide information on recovery measures to be taken by Environment and Climate Change Canada and other jurisdictions and/or organizations involved in the conservation of the species. Implementation of this strategy is subject to appropriations, priorities, and budgetary constraints of the participating jurisdictions and organizations.

The recovery strategy sets the strategic direction to arrest or reverse the decline of the species, including identification of critical habitat to the extent possible. It provides all Canadians with information to help take action on species conservation. When critical habitat is identified, either in a recovery strategy or an action plan, there may be future regulatory implications, depending on where the critical habitat is identified. SARA requires that critical habitat identified within a national park named and described in Schedule 1 to the Canada National Parks Act, the Rouge National Urban Park established by the Rouge National Urban Park Act, a marine protected area under the Oceans Act, a migratory bird sanctuary under the Migratory Birds Convention Act, 1994 or a national wildlife area under the Canada Wildlife Act be described in the Canada Gazette, after which prohibitions against its destruction will apply. For critical habitat located on other federal lands, the competent minister must either make a statement on existing legal protection or make an order so that the prohibition against destruction of critical habitat applies. For any part of critical habitat located on non-federal lands, if the competent minister forms the opinion that any portion of critical habitat is not protected by provisions in or measures under SARA or other Acts of Parliament, or the laws of the province or territory, SARA requires that the Minister recommend that the Governor in Council make an order to prohibit destruction of critical habitat. The discretion to protect critical habitat on non-federal lands that is not otherwise protected rests with the Governor in Council

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A preliminary draft of this recovery strategy was prepared by Talena Kraus (Artemis Eco-Works). Subsequent drafts were developed by Lee Voisin and Jocelyn Sherwood (Environment and Climate Change Canada, Canadian Wildlife Service – Ontario). This recovery strategy benefited from input, review and suggestions from the following individuals and organizations: Krista Holmes, Burke Korol, Angela McConnell, Judith Girard, Liz Sauer, Ken Corcoran, Elizabeth Rezek (Environment and Climate Change Canada, Canadian Wildlife Service – Ontario), and Eric Snyder, Amanda Fracz and Glenn Desy (Ontario Ministry of Natural Resources and Forestry).

Acknowledgement and thanks is given to all other parties that provided advice and input used to help inform the development of this recovery strategy including various Aboriginal organizations and individuals, individual citizens, and stakeholders who provided input and/or participated in consultation meetings.

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Executive Summary

Branched Bartonia is an annual herb that typically grows with Sphagnum moss, in open wetlands. It is 10 to 40 cm tall with a green or purple, angled stem. It has small and scale-like, alternate leaves, and a few to numerous flowers that are small, white, and four-lobed. The species reproduces by seed, but it is not known how long seeds remain viable in the seed bank. Flowering occurs from late July through to September and fruiting occurs from late August to late October and possibly November. Dispersal mechanisms and pollinators of this species are not well known.

There are three subspecies of Branched Bartonia in North America: Bartonia paniculata paniculata, B.p. texana, and B.p. iodandra. The only subspecies that is at risk in Canada is the subspecies B.p. paniculata, which is the focus of this recovery strategy.

Branched Bartonia is found along much of the Atlantic Coastal Plain in the United States but only in one area in Canada. The Ontario population is considered an Atlantic Coastal Plain disjunct, as it occurs in the Muskoka-Parry Sound area of Ontario and is isolated from its main range in the United States. This disjunct population is approximately 600 km from the main population, and is genetically distinct from it. It is believed that seeds of the subspecies were moved to Canada as a result of glaciation.

Branched Bartonia was designated as Threatened by the Committee on the Status of Endangered Wildlife in Canada (COSEWIC) in 2003, and is ranked as Threatened by the province of Ontario and the federal Species at Risk Act (SARA). It is estimated that <1% of the global population is located in Canada.

The main threat to this species is encroachment into its habitat by the invasive shrub, Glossy Buckthorn. Other possible threats include encroachment of Non-native Common Reed, railway embankment enlargement, trampling by humans, off-road vehicle use, peat harvesting, global reduction of pollinators and climate change.

The population and distribution objective for this species is to maintain, and where feasible, increase the distribution and abundance of Branched Bartonia at extant local populations in Canada. Maintaining the current populations and their habitat would provide protection for plants not previously found and for seeds that may be lying dormant in the seedbank.  

Critical habitat for Branched Bartonia is fully identified in this recovery strategy due to meeting the population and distribution objective, and is based on habitat occupancy and habitat suitability. Broad strategies to be taken to address the threats to the survival and recovery of this species are presented in the section on Strategic Direction for Recovery.

One or more action plans will be posted on the Species at Risk Public Registry for Branched Bartonia by 2022.

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Recovery Feasibility Summary

Based on the following four criteria that Environment and Climate Change Canada uses to establish recovery feasibility, there are unknowns regarding the feasibility of recovery of Branched Bartonia. In keeping with the precautionary principle, this recovery strategy has been prepared as per section 41(1) of SARA, as would be done when recovery is determined to be technically and biologically feasible. This recovery strategy addresses the unknowns surrounding the feasibility of recovery.

1. Individuals of the wildlife species that are capable of reproduction are available now or in the foreseeable future to sustain the population or improve its abundance.
Yes. There are local populations at each currently known location that have been found over multiple years, indicating the ability of the plant to reproduce successfully over a long period (e.g., >20 years) of time (COSEWIC 2003; Brinker 2006). The core range of the subspecies is 600 km away from the Canadian population, and because of this, there is little to no rescue effect available for the species (COSEWIC 2003). Since the development of the COSEWIC report in 2003, new local populations have been found (Natural Heritage Information Centre [NHIC] 2014). There has been survey evidence of demographic fluctuation with some local populations found 14 years apart, but not in subsequent years. This would suggest that seeds can remain viable in the seed bank, even though mature plants may not be found during a survey.
As the minimum viable population size of the species has not been investigated in Ontario, the loss of part or whole local populations would further fragment the disjunct Canadian population and render it more susceptible to extirpation.
2. Sufficient suitable habitat is available to support the species or could be made available through habitat management or restoration.
Unknown. The suitable habitat that is currently available to the species appears sufficient to support the populations at all locations; however, there are uncertainties regarding the suitable habitat conditions for the Canadian population of Branched Bartonia. The species has been found repeatedly in known locations since its initial discovery in the province, and much of the habitat remains in good to excellent condition (COSEWIC 2003; Brinker 2006). The occupied habitat differs amongst several locations in Canada, and more research to determine the specific range of habitat preferences should be conducted. In addition, there has been some research that suggests Branched Bartonia may be reliant on a fungal associate (Matthews et al. 2009). Further research should be conducted to confirm if Branched Bartonia is in need of a specific fungal associate, as that would be an essential component of suitable habitat.
3. The primary threats to the species or its habitat (including threats outside Canada) can be avoided or mitigated.
Yes. The primary threat to this species and its habitat is the spread of invasive species in some of the wetlands in which Branched Bartonia populations occur (COSEWIC 2003; Brinker 2006). There are factsheets and best practice guides available detailing control methods for Glossy Buckthorn and Non-native Common Reed (Phragmites australis); these control methods have been shown to be effective and further research into biological controls is underway as well (Upper Thames River Conservation Authority 2015; Michigan Department of Natural Resources 2012). Research to address knowledge gaps and actions to address widespread threats such as climate change and global reduction of pollinators would assist in the recovery of the species.
4. Recovery techniques exist to achieve the population and distribution objectives or can be expected to be developed within a reasonable timeframe.
Yes. The recovery techniques necessary to achieve the population and distribution objectives exist and are detailed under (3) above; however, as the species contains several small local populations in Canada, large scale threats or disturbance could cause some local populations to be extirpated. Continuous monitoring and further understanding of the species’ biology and threats will need to be conducted to allow for the objectives to be met. Further information on the life cycle of Branched Bartonia would also assist in developing effective recovery techniques (e.g. propogation, or reintroduction) in the future.

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1. COSEWIC* Species Assessment Information

Date of Assessment:
November 2003
Common Name (population):
Branched Bartonia
Scientific Name:
Bartonia paniculata ssp. paniculata
Reason for Designation:
A cryptic wetland annual species of Atlantic Coastal Plain affinity, highly restricted both geographically and ecologically and present at only six of seven documented sites. Ontario populations are disjunct by about 600 km from the main range of the species with little potential for a rescue effect. The greatest potential risk is from the invasive shrub, glossy buckthorn, at two localities.
Canadian Occurrence:
COSEWIC Status History:
Designated Special Concern in April 1992. Status re-examined and designated Threatened in November 2003.

*COSEWIC (Committee on the Status of Endangered Wildlife in Canada).

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2. Species Status Information

In Canada, Branched Bartonia (Bartonia paniculata ssp. paniculata) is listed as ThreatenedFootnote2 on Schedule 1 of the federal Species at Risk Act (SARA). In Ontario, the species is listed as ThreatenedFootnote3 under the Endangered Species Act, 2007(S.O. 2007, ch.6) (ESA 2007).

Branched Bartonia is globally common, with a rank of G5T5Footnote4. It is not ranked in the United States and is Nationally Imperiled (N2) in Canada (Appendix A) (NatureServe 2015). In Canada, the species occurs only in Ontario, where it is Imperiled (S2) (Appendix A) (NatureServe 2015). It is unranked (SNR) in much of its range in the United States (Alabama, Connecticut, District of Columbia, Florida, Georgia, Illinois, Indiana, Kentucky, Louisiana, Maryland, Massachusetts, Michigan, Mississippi, Oklahoma, Pennsylvania, Rhode Island, South Carolina, Tennessee, Texas), Apparently Secure (S4) in Arkansas and New Jersey, Vulnerable (S3) in Virginia, Vulnerable to Imperiled (S2S3) in North Carolina, Imperiled (S2) in Delaware and Critically Imperiled (S1) in Maine, Missouri, New Hampshire, New York and West Virginia (Appendix A) (NatureServe 2015).

It is not known precisely how much of the global population range is in Canada, but given how common both the species and the subspecies are in the United States, the number is certain to be less than one percent. However, the conservation importance of the Ontario population is likely quite high based on recent genetic work demonstrating that the Ontario population has high genetic divergence from the core populations, and diverged earlier than previously believed (Ciotir et al. 2013).

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3. Species Information

3.1 Species Description

Branched Bartonia has three currently recognized subspecies: Bartonia paniculata paniculata, B.p. texana, and B.p. iodandra (Ciotir et al. 2013). Only subspecies B.p. paniculata occurs in Canada (in Ontario) (Hingmand and Penskar 1996; COSEWIC 2003; Mathews et al. 2009; Ciotir et al. 2013), and mention of Branched Bartonia throughout this recovery strategy refers to subspecies B.p. paniculata, unless otherwise stated. This species is also referred to as Panicled Screwstem or Twining Screwstem, and the names may be used to refer to other subspecies (e.g., ssp. texana) that do not occur in Canada (Gillett 1959; Hingman and Penskar 1996; COSEWIC 2003).

Branched Bartonia is an annual herb that is 10-40 cm tall with a green or purple, angled stem, though it generally appears much shorter as it often grows in Sphagnum moss (COSEWIC 2003). The leaves are small and scale-like, and alternate, with a few to numerous flowers that are small, white, and four-lobed (COSEWIC 2003). These alternate leaves and small, white flowers are important identifying features that distinguish Branched Bartonia from other plants. Reproduction of Branched Bartonia is not completely understood, although it has been confirmed that the subspecies reproduces by seed (COSEWIC 2003). It is not known how long seeds may remain viable in the seed bankFootnote5 (COSEWIC 2003). Flowering occurs from late July through to September and fruiting occurs from late August to late October and possibly into November (Gillett 1959; Higman and Penskar 1996). Dispersal mechanisms and potential pollinators for this species are not well known. Unless the species is in bloom or fruiting, Branched Bartonia is very inconspicuous, due to its small size and growth among Sphagnum mosses.

The genus Bartonia is believed to be saprophyticFootnote 6 (Nilsson and Skvarla 1969), though there is little evidence for this in B.p. paniculata specifically. Branched Bartonia’s small leaves suggest that photosynthesis is not effective (Reznicek and Whiting 1976; COSEWIC 2003). Because of this, it has been hypothesized, but not confirmed, that Branched Bartonia is heterotrophicFootnote 7 (COSEWIC 2003).

3.2 Population and Distribution

Branched Bartonia is found along much of the Atlantic Coastal Plain in the United States, from Massachusetts, south to Florida, west to Texas and north to Arkansas and Tennessee, with isolated populations in Michigan, Wisconsin and Ontario, and is considered to be common through the majority of its range (see Figure 1) (COSEWIC 2003; Hill 2003; Mathews et al. 2009).

Within Canada, Branched Bartonia (subspecies paniculata) is found only in Ontario. The Ontario population is disjunct from its main range in the United States, and because of this, it is referred to as an Atlantic Coastal Plain disjunctFootnote 8 (Reznicek and Whiting 1976; Reznicek 1994; Ciotir et al. 2013). The wetland areas in which the Ontario populations are found are within the Georgian Bay Ecoregion 5EFootnote 9 (COSEWIC 2003; Brinker 2006). There are 10 known extant local populations in the Muskoka-Parry Sound/Muskoka area, near Georgian Bay on the Canadian Shield (NHIC 2014). Three of these known local populations have been found since the development of the COSEWIC (2003) report.

Based on recent data, the Canadian population is estimated to be about 767 plants (See Figure 2; Table 1); however, Branched Bartonia is easily overlooked during surveys and often occurs in extensive habitat that requires significant surveying effort (COSEWIC 2003; Brinker 2006). Because of these factors, and the discovery of three new local populations since the publication of the COSEWIC Update Status Report (2003), the actual Canadian population size may be underestimated. Based on the 2003 COSEWIC Update Status Report, the extent of occurrence Footnote 10 and area of occupancy Footnote11 are noted as stable, at 400 km2 and <1 km2, respectively.

The main range of the subspecies is approximately 600 km southwest of the Canadian population (COSEWIC 2003). Since the known Canadian population is clearly isolated from the larger population in the United States, there is little to no possibility of a rescue effectFootnote 12 at this time. Branched Bartonia was found relatively recently in Canada (1973) (Reznicek and Whiting 1976); it is therefore possible that more populations exist than are currently known, and may be found as additional surveys of suitable habitat are conducted.

Figure 1. North American Distribution map of Branched Bartonia (subspecies Bartonia paniculata paniculata) (COSEWIC 2003).
Long description for Figure 1

Figure 1 shows a map of the North American distribution of Branched Bartonia (subspecies Bartonia paniculata paniculata). In Canada, the distribution exists in Ontario within the Georgian Bay Ecoregion. In the United States the distribution exists from Massachusetts, south to Florida, west to Texas and north to Arkansas and Tennessee, with isolated populations in Michigan, Wisconsin.

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Table 1. Branched Bartonia local populations in Ontario.
Local PopulationPlant CountHabitat TypeReferences
Axe Lake159Low shrub shore fen/bog complexCOSEWIC 2003; Brinker 2006;
Barrett Lake4Low shrub shore fenCOSEWIC 2003; Brinker 2006;
MacTier Bog120Moderately rich poor fen; poor fenCOSEWIC 2003; Brinker 2006;
Medora Lake Road Fen46Moderately rich poor fenCOSEWIC 2003; Brinker 2006;
O’Donnell Point44Moderately rich poor fenCOSEWIC 2003; Brinker 2006;
Bala Bog57Moderately rich poor fenCOSEWIC 2003; Brinker 2006;
Loon Lake Bog100Poor fenCOSEWIC 2003; Brinker 2006;
Little Hellagone Lake Fen46Poor fenNHIC 2014
Torrance Barrens62Poor fenNHIC 2014
Jevins & Silver Lake Conservation Area129Poor fenNHIC 2014

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Figure 2. Locations of Branched Bartonia in Canada. There are ten extant populations in Canada.
Long description for Figure 2

Figure 2 shows a map of the locations of Branched Bartonia in Canada. There are ten extant populations in Canada. Locations of extant populations occur at Axe Lake, Barrett Lake, Medora Lake Road Fen, O’Donnell Point, Bala Bog, Little Hellagone Lake Fen, Torrance Barrens and Jevins & Silver Lake Conservation Area.

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3.3 Needs of the Branched Bartonia

In Ontario, Branched Bartonia is found in open graminoid or low shrub acidic wetlands, with nutrient poor, peat or sandy soils. Branched Bartonia grows within wetland complexes, including bogs or fens with scattered Tamarack (Larix laricina) and Black Spruce (Picea mariana) and Sphagnum mosses. Typically, it occurs on the Canadian Shield between low ridges of granitized rock. Associated species include (but are not limited to): Black Chokeberry (Aronia melanocarpa), Virginia Cotton-grass (Eriophorum virginicum), Mountain-holly (Nemopanthus mucronatus), White-fringed Orchid (Platanthera blephariglottis), Rose Pogonia (Pogonia ophioglossoides), White Beak-rush (Rhynchospora alba) and Virginia Chain Fern (Woodwardia virginica) (COSEWIC 2003; Brinker 2006). It sometimes occurs with other Atlantic Coastal Plain species, which appears to be true within all of its range and not solely in Ontario (Gillett 1959; Reznicek and Whiting 1976; Higman and Penskar 1996; COSEWIC 2003; Hill 2003; Brinker 2006; Georgian Bay Biosphere Reserve 2015).

Branched Bartonia is dependent on the openness of habitat, substrate type and continuous moisture for establishment of shoots and plant health (COSEWIC 2003; Brinker 2006). Under natural conditions the hydrology of these habitats are typically stable, but do fluctuate seasonally. Thus, the plant is particularly susceptible to habitat drying or water level stabilization that may provide conditions that favour shrub encroachment (Reznicek 1994; Higman and Penskar 1996; COSEWIC 2003; Hill 2003; Brinker 2006). Dependence on openness is based on the shade intolerance of shoots and the lack of competition for sunlight with invasive plants (Brinker 2006).

3.4 Needs of the Branched Bartonia

Branched Bartonia is biologically limited to specific wetland habitat within its Canadian range. Branched Bartonia reproduces by seed; however, specific reproductive biology is unknown (COSEWIC 2003).

Although yet to be confirmed, it is possible that Branched Bartonia relies on a fungal association with specific mycorrhizal fungi (Mathews et al. 2009). If the presence of a specific fungus is required by Branched Bartonia, then the species would be limited by the fungus’ distribution in Canada.

In addition, most of the extant populations occupy an area of less than a few square kilometres. Such populations may be vulnerable to local chance events such as storms and certain human disturbances.

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4. Threats

4.1 Threat Assessment

This section highlights the threats outlined in Table 2, emphasizes key points, and provides additional information. The threats are presented in decreasing order of level of concern within each category.

Table 2. Threat Assessment Table
Key PointsThreatLevel of ConcernNote a of Table 2ExtentOccurrenceFrequencySeverityNote b of Table 2Causal CertaintyNote c of Table 2
Exotic, Invasive, or Introduced Species/GenomeGlossy BuckthornHighLocalizedCurrentContinuousHighHigh
Exotic, Invasive, or Introduced Species/GenomeNon-native Common ReedMediumLocalizedAnticipatedContinuousModerateLow
Climate and Natural DisastersClimate changeMediumWidespreadUnknown /AnticipatedContinuousModerateMedium
Changes in Ecological Dynamics or Natural ProcessesGlobal reduction of pollinatorsMediumWidespreadCurrent/
Changes in Ecological Dynamics or Natural ProcessesRailway embankment expansionLowLocalizedAnticipated/ UnknownOne-timeLowLow
Disturbance or HarmTrampling by humans and ATVsLowLocalizedUnknown/ AnticipatedSeasonalLowLow
Disturbance or HarmPeat harvestingLowUnknownUnknownSeasonalLowLow

Footnotes of Table 2

Footnote a

Level of Concern: signifies that managing the threat is of (high, medium or low) concern for the recovery of the species, consistent with the population and distribution objectives. This criterion considers the assessment of all the information in the table.

Return to footnote a referrer of Table 2

Footnote b

Severity: reflects the population-level effect (High: very large population-level effect, Moderate, Low, Unknown).

Return to footnote b referrer of Table 2

Footnote c

Causal certainty: reflects the degree of evidence that is known for the threat (High: available evidence strongly links the threat to stresses on population viability; Medium: there is a correlation between the threat and population viability e.g. expert opinion; Low: the threat is assumed or plausible).

Return to footnote c referrer of Table 2

4.2 Description of Threats

Exotic, Invasive, or Introduced Species/Genome

Glossy Buckthorn: The invasive shrub, Glossy Buckthorn (Rhamnus frangula) is encroaching upon three local populations of Branched Bartonia (Brinker 2006). Glossy Buckthorn can spread quickly and form dense thickets (Catling and Zorebski 1994; Michigan Department of Natural Resources 2012; Upper Thames River Conservation Authority 2015). As such it can eliminate open habitat, causing competition for space, over shading, and drying of habitat, thereby altering habitat conditions required by Branched Bartonia. Given that this species is present near three local populations, along with its invasive nature and ability to spread quickly and densely, it is the most concerning threat for Branched Bartonia (COSEWIC 2003).

Non-native Common Reed: The invasive subspecies of Non-native Common Reed (Phragmites australis) is present near one local population of Branched Bartonia and may be spreading closer to the local population along a railway corridor (Brinker 2006). The effects of Common Reed are similar to that of Glossy Buckthorn as this species aggressively invades open wet areas, outcompetes local flora, and occupies large areas in high density (Mazur et al. 2014). As it is not currently found at any Branched Bartonia locations, it is a threat that should be monitored rather than one that requires immediate active mitigation.

Disturbance or Harm

Trampling by humans and all-terrain vehicles: Evidence of low levels of human activities such as hunting and all-terrain vehicle (ATV) use have been noted at two locations where Branched Bartonia is present, but the locations are relatively inaccessible and this threat was not noted to be of high concern (Brinker 2006). This species can be difficult to see due to its tendency to grow in Sphagnum moss (COSEWIC 2003), which could increase its susceptibility to being trampled during hunting or surveying activities. As Branched Bartonia has quite a short growing season, trampling of mature plants from late July to late October could severely impact seed production at small local populations. Extensive foot traffic or ATV use in Branched Bartonia habitat could cause the development of compacted trails, rendering the habitat unsuitable for seed establishment and altering the suitable habitat conditions required by the species. Evidence of trail creation from foot traffic and ATVs is already present at some local populations (Brinker 2006).

Peat Harvesting: Branched Bartonia is found in wetlands with peat substrates, therefore removal of peat in the wetlands supporting Branched Bartonia would damage and destroy habitat for the species. At present, this threat is not known to occur at any sites occupied by the species. At least two populations are located in areas where peat harvesting is prohibited (i.e. a provincial park and a conservation area).

Climate and Natural Disasters

Climate Change: The wetlands in which this species is found may be sensitive to warming temperatures and acidification due to climate change (Higman and Penskar 1996). Warming of the wetlands may also lead to drier conditions, which would negatively impact the species. Branched Bartonia is a wetland species that is reliant on continuous soil moisture and specific habitat conditions (see section 3.3). As such, changes to the water levels or chemistry in, or flowing to, the wetland it inhabits could be detrimental to the species. Considering the rarity of the species in Canada, and the relatively small amount of plants in each local population, Branched Bartonia is very vulnerable to catastrophic events, and the loss of a single or multiple local populations would further fragment the Canadian population and make it more susceptible to current and anticipated threats.

Changes in Ecological Dynamics or Natural Processes

Railway embankment expansion: There is one local population near a railway embankment and it would likely be destroyed if that embankment were expanded (COSEWIC 2003; Brinker 2006). It is not known if plans to expand the embankment exist, although legislation and regulatory practices exist to address threats that would impact local populations of species at risk.

Global reduction of pollinators: Although not confirmed, it is assumed that Branched Bartonia is dependent on pollinators for reproduction (COSEWIC 2003), and the species has been observed to be visited by pollinators such as moths (Korol pers. comm. 2015). A number of factors are suspected to be contributing to the decline in insect pollinator populations globally and in Canada, including loss of habitat and food sources, diseases, viruses, pests, and pesticide exposure (Health Canada 2014). Notably, there is growing evidence to suggest that pesticides, including neonicotinoids, may be having negative effects on pollinator populations due to their toxic properties and persistence in soil and water (van der Sluijs et al. 2013; Cutler et al. 2014). Currently, the extent to which the decline in pollinator populations may impact the Branched Bartonia is not known.

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5. Population and Distribution Objective

The population and distribution objective for this species is:

  • To maintain, and where feasible, increase the distribution and abundance of Branched Bartonia at extant local populations in Canada.

Branched Bartonia is an Atlantic Coastal Plain species. The Ontario population is disjunct from the main population and genetically distinct (Higman and Penskar 1996; COSEWIC 2003; Ciotir et al. 2013). Its dispersal mechanisms are unknown. With the low number of locations, the loss of one or a few would fragment the Canadian population further and render it more susceptible to extirpation.

The area of occupancy of Branched Bartonia in Canada is estimated to be <1 km2 (COSEWIC 2003). Based on the most recent plant counts at each local population, the abundance of the Canadian population of Branched Bartonia is estimated to be around 767 plants; however, the species is cryptic (i.e., very hard to see unless flowering), and populations tend to fluctuate in size due to annual habitat conditions and the varying dormancy period of Branched Bartonia seeds (COSEWIC 2003; Brinker 2006; NHIC 2014). Therefore, maintaining plant and seed viability will be important for the local populations to remain stable.

Maintaining the current local populations would provide protection for dormant seeds that may allow for increased abundance and range expansion within existing habitat. Surveys to better understand the natural range of variation in population size, and habitat associations will be required to meet the population and distribution objective. Management of Glossy Buckthorn and Common Reed is also likely to be required in order to maintain the size and extent of Branched Bartonia for at least two locations (Brinker 2006). Activities, such as habitat management in adjacent wetland ecosystems, may encourage expansion of the Branched Bartonia into suitable but currently unoccupied habitats in its current range in Ontario and may assist with recovery of the species.

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6. Broad Strategies and General Approaches to Meet Objectives

6.1 Actions Already Completed or Currently Underway

Ongoing monitoring of known local populations, and searches for new locations in habitat deemed by experts to be suitable, are undertaken by the Parry Sound office of the Ontario Ministry of Natural Resources and Forestry (OMNRF) (J. Rouse, pers. comm. 2015). Branched Bartonia receives general habitat protection under the Endangered Species Act, 2007 (as of June 30, 2013) and is a species tracked by the Natural Heritage Information Centre (NHIC). Preliminary genetic work on the Ontario population was completed by Ciotir et al. (2013). The Georgian Bay Biosphere Reserve and the Muskoka Watershed Council have webpages with information on the species and links to, or outlines of, general stewardship guidance (Georgian Bay Biosphere Reserve 2015; Muskoka Watershed Council 2015).

6.2 Strategic Direction for Recovery

Table 3. Recovery Planning Table
Threat or LimitationPriorityNote d of Table 3Broad Strategy to RecoveryGeneral Description of Research and Management Approaches
Knowledge gapsHighDetermine local population sizes at known locations and follow fluctuations between years

Determine specific hydrologic and other needs (e.g. mycorrhizal fungi) of the species

Better define and quantify the vegetation communities it occurs in

Develop a survey protocol for the species to minimize survey impact on the habitat and reduce the occurrence of human disturbance (i.e. trampling) during surveys
  • Conduct standard local population surveys, determine if fluctuations follow any pattern over time
  • Conduct studies to assess the hydrology of the habitat and its influence on the species
  • Conduct a study to determine presence or absence of mycorrhizal fungi (or other indications that species is saprophytic)
  • Conduct studies to determine which species of Sphagnum it is associated with and measure overstory cover percentage in known locations
  • Continue genetic studies to further understand the life history of this subspecies
  • Develop and evaluate a standard survey/monitoring protocol
  • Conduct surveys using the developed survey protocol to address knowledge gaps such as: longevity, natural variations in population size, pollination, pollinators, seed establishment, and habitat associations
Glossy BuckthornHighEvaluate and implement control measures
  • Assess possible control measures (e.g., cutting, pulling, chemical) and implement those most likely to be effective in the locations threatened by Glossy Buckthorn
  • Record and report on results to inform further similar work for this and other species at risk
Common ReedMediumMonitor spread of Common Reed near Branched Bartonia locations
  • Regular (annual/biennial) monitoring of the location of Common Reed
  • If necessary, assess and implement control measures
Disturbance or Harm; Natural Systems ModificationLowCommunicate with appropriate stakeholders and the public regarding best management practices
  • Identify relevant landowners and stakeholders
  • Create and provide communication and outreach information to enhance stewardship of the species
Climate ChangeLowDevelop a plan to mitigate the potential impacts of climate change
  • Connect with other agencies working on climate change scenarios in Ontario to guide creation of climate change predictions and measures to mitigate their impact

Footnotes of Table 3

Note d

"Priority" reflects the degree to which the broad strategy contributes directly to the recovery of the species or is an essential precursor to an approach that contributes to the recovery of the species.

Return to note d referrer of table 3

6.3 Narrative to Support the Recovery Planning Table

Current knowledge of local populations sizes and fluctuations is somewhat lacking, as the species was not found in Canada until 1973 (Reznicek and Whiting 1976) and surveys were not conducted with regularity until relatively recently.

Systematic and regular surveys will provide much more accurate information about local population sizes and their fluctuations. Studies to address knowledge gaps will provide information to inform habitat management, control and/or mitigation of human-caused or natural changes to hydrology. Research on methods to control invasive species such as Glossy Buckthorn and Common Reed will benefit Branched Bartonia through identification of mitigation measures for these threats. Information obtained from research and species surveys provide a strong basis for developing communication and outreach materials that can become part of stewardship initiatives and resources that could reduce or prevent many of the listed threats.

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7. Critical Habitat

7.1 Identification of the Species’ Critical Habitat

Section 41(1)(c) of SARA requires that recovery strategies include an identification of the species’ critical habitat, to the extent possible, as well as examples of activities that are likely to result in its destruction. Under section 2(1) of SARA, critical habitat is “the habitat that is necessary for the survival or recovery of a listed wildlife species and that is identified as the species’ critical habitat in the recovery strategy or in an action plan for the species”.

This federal recovery strategy identifies critical habitat for Branched Bartonia in Canada to the extent possible, based on the best available information as of August 2015. Critical habitat is identified for the 10 extant local populations of Branched Bartonia in Ontario (see Figure 3 and Table 4), and is sufficient to meet the population and distribution objective; therefore, a schedule of studies is not required. Additional critical habitat may be added in the future, if new or additional information supports the inclusion of areas beyond those currently identified (e.g., new populations are found or existing, extant local populations expand into adjacent areas).

Critical habitat identification for Branched Bartonia is based on two criteria: habitat suitability and habitat occupancy.

7.1.1 Habitat Suitability

Habitat suitability relates to areas possessing a specific set of biophysical attributes that can support individuals of the species in carrying out essential aspects of their life cycle. At extant locations in Canada, Branched Bartonia is typically found growing with Sphagnum moss in the peat soils of wetlands containing Tamarack (Larix laricinia) and Black Spruce (Picea mariana) trees, in areas where the canopy is open. Associated vegetation may include but not be limited to Black Chokeberry (Aronia melanocarpa), Virginia Cotton-grass (Eriophorum virginicum), Tamarack (Larix laricina), Mountain-holly (Nemopanthus mucronatus), White-fringed Orchid (Platanthera blephariglottis), Rose Pogonia (Pogonia ophioglossoides), White Beak-rush (Rhynchospora alba) and Virginia Chain Fern (Woodwardia virginica).

Suitable habitat for Branched Bartonia is currently defined as the extent of the biophysical attributes at known local populations. These biophysical attributes, which capture the characteristics required by the species to carry out its life processes, include:

  • Open, graminoid or low shrub wetland
    • wet sand or peat soils
  • water pH that is slightly acidic to neutral
  • presence of Sphagnum mosses
  • presence of scattered Tamarack and Black Spruce

It is expected that other biophysical attributes (especially the identification of specific Sphagnum subspecies it occurs with) may be identified as more becomes known about the species.

In Ontario, suitable habitat for Branched Bartonia is described using the Northern Ontario Wetland Evaluation System (OWES) (MNRF 2014). The OWES framework provides a standardized approach to the interpretation and delineation of wetland boundaries. The OWES approach classifies wetlands not only by vegetation community but also considers hydrology and topography, and as such encompasses the biophysical attributes of the habitat for Branched Bartonia. In addition, the OWES terminology is familiar to many land managers and conservation practitioners who have adopted this tool as the standard approach for northern wetlands in Ontario and is typically used by the province of Ontario to aid land use planning.

Within the OWES, wetland habitat is described by the vegetation community boundary. In addition, the area within 120 m of this wetland habitat boundary contributes to maintaining microhabitat conditions and the functional integrity of the wetland and is included as critical habitat. This boundary will include habitat occupied by Branched Bartonia and the surrounding areas that provide suitable habitat conditions (e.g., open canopy) to carry out essential life processes for the species and should allow for natural processes related to population dynamics and reproduction (e.g., dispersal and pollination) to occur. This 120 m boundary will also prevent invasive species or pollution from impacting the Branched Bartonia population. 120 m is also the area identified within the Ontario’s Natural Heritage Reference Manual (OMNR 2010), as the area where any development may adversely affect the ecological function of a wetland.

As wetland habitats have high ecological value (MNRF 2014), and are vulnerable to degradation (e.g., from non-natural water level fluctuations, invasive plant species and pollution) (Brinker 2006), a habitat-based approach to critical habitat identification is important. This larger area around the plant may also promote ecosystem resilience to invasive species (i.e., Glossy Buckthorn) while protecting what are typically rare plant communities in Ontario and providing room for population expansion. While there is a lack of data regarding the dispersal distances of Branched Bartonia (COSEWIC 2003), the more recent discovery of local populations at Little Hellangone Lake Fen, Torrance Barrens and Jevins & Silver Lake Conservation Reserve indicate that the species may be present in the seedbank of surrounding suitable habitat.

7.1.2 Habitat Occupancy

The habitat occupancy criterion refers to areas of suitable habitat where there is a reasonable degree of certainty of current use by the species.

Habitat is considered occupied when:

  • One or more Branched Bartonia individuals have been observed within the past 20 years.

Occupancy is based on recent occurrence reports available for all known extant local populations from Ontario’s Conservation Data Centre (Natural Heritage Information Centre) and the Committee on the Status of Endangered Wildlife in Canada (COSEWIC). Branched Bartonia is very cryptic. There are local populations where the subspecies was found 14 years apart but not in the intervening years (Brinker 2006), which could be due to cryptic plants, or demonstrate the species’ potential for extended dormancy (the length of time for which seeds remain viable in the seedbank is currently not known). The twenty-year windowFootnote13 (since 1996) corresponds to the threshold beyond which a record is considered historical in Conservation Data Centres (i.e. 20 years for the Ontario Natural Heritage Information Centre (NHIC)) and allows for the inclusion of data for all ten local populations known to be extant. Additional local populations may exist, as site accessibility is low in some suitable habitat areas. If new observations become available, they will be considered for the identification of additional critical habitat.

7.1.3 Application of the Criteria to Identify Critical Habitat for Branched Bartonia

Critical habitat for Branched Bartonia is identified as the extent of suitable habitat (7.1.1) where the occupancy criterion (7.1.2) is met. The area within a radial distance of 120 m of the occupied wetland habitat is also included as critical habitat.

In Ontario, as noted above, suitable habitat for Branched Bartonia is most appropriately identified by the OWES wetland type. At the present time, 5 occupied wetlands have been evaluated by the OWES and assigned a wetland type. For the locations that have not yet been evaluated by the OWES, Ontario base mapping wetland boundariesFootnote14 are used and wetland type confirmed using high-resolution aerial photography. Critical habitat is located within these boundaries where the biophysical attributes described in section 7.1.2 are found and where the occupancy criterion is met (section 7.1.1). When wetland boundaries are evaluated the identification of critical habitat will be updated.

Application of the critical habitat criteria to the best available information identifies critical habitat for the ten known extant local populations of Branched Bartonia in Canada (Figure 3, Table 4), totaling approximately 656 haFootnote 15. While critical habitat is identified for ten extant local populations, some of these local populations are near each other, resulting in the critical habitat grid squares of some local populations to overlap and thus appear to be represented as one. Refer to Table 4 for the names and grid square identification for each of these ten local populations.

Critical habitat for the Branched Bartonia is presented using 1 x 1 km standardized UTM grid squares. The UTM grid squares presented in Figure 3 are part of a standardized grid system that indicates the general geographic areas containing critical habitat, which can be used for land use planning and/or environmental assessment purposes. In addition to providing these benefits, the 1 km x 1 km UTM grid respects provincial data-sharing agreements in Ontario. Critical habitat within each grid square occurs where description of habitat suitability (section 7.1.1) and habitat occupancy (section 7.1.2) are met. More detailed information on critical habitat to support protection of the species and its habitat may be requested on a need-to-know basis by contacting Environment and Climate Change Canada – Canadian Wildlife Service

Figure 3. Grid squares that contain critical habitat for the Branched Bartonia in Canada. Critical habitat for the Branched Bartonia occurs within these 1 x 1 km standardized UTM grid squares (red shaded squares), where the description of habitat suitability (section 7.1.1) and habitat occupancy (section 7.1.2) are met.
Long description for Figure 3

Figure 3 shows a map of critical habitat for the Branched Bartonia in Canada using grid squares. Critical habitat for the Branched Bartonia occurs within the 1 x 1 km standardized UTM grid squares. There are 9 grid squares at Little Hellangone Lake Fern, 7 at O’Donnell Point, 6 at Loon Lake Bog, 4 at Jevins & Silver Lake Conservation Reserve, 4 at Medora Lake Road, 4 at Torrance Barrens, 3 at MacTier Bog, 3 at Bala Bog, 2 at Barrett Lake and 2 at Axe Lake.

Table 4. Grid squares that contain critical habitat for the Branched Bartonia in Canada. Critical habitat for the Branched Bartonia occurs within these 1 x 1 km standardized UTM grid squares where the description of habitat suitability in section 7.1.1 and habitat occupancy (section 7.1.2) are met.
Local Population1 x 1 km Standardized UTM grid square IDNote e of Table 4UTM Grid Square CoordinatesNote f of Table 4
UTM Grid Square CoordinatesNote f of Table 4
Land TenureNote g of Table 4
O’Donnell Point17TNK79125710004992000Non-federal land
O’Donnell Point17TNK79135710004993000Non-federal land
O’Donnell Point17TNK79225720004992000Non-federal land
O’Donnell Point17TNK79235720004993000Non-federal land
O’Donnell Point17TNK79325730004992000Non-federal land
O’Donnell Point17TNK79415740004991000Non-federal land
O’Donnell Point17TNK79425740004992000Non-federal land
Little Hellangone Lake Fen17TNK99485940004998000Non-federal land
Little Hellangone Lake Fen17TNK99495940004999000Non-federal land
Little Hellangone Lake Fen17TNK99575950004997000Non-federal land
Little Hellangone Lake Fen17TNK99585950004998000Non-federal land
Little Hellangone Lake Fen17TNK99595950004999000Non-federal land
Little Hellangone Lake Fen17TNL90315930005001000Non-federal land
Little Hellangone Lake Fen17TNL90325930005002000Non-federal land
Little Hellangone Lake Fen17TNL90405940005000000Non-federal land
Little Hellangone Lake Fen17TNL90415940005001000Non-federal land
MacTier Bog17TNK99665960004996000Non-federal land
MacTier Bog17TNK99675960004997000Non-federal land
MacTier Bog17TNK99765970004996000Non-federal land
Bala Bog17TPK08596050004989000Non-federal land
Bala Bog17TPK08686060004988000Non-federal land
Bala Bog17TPK08696060004989000Non-federal land
Barrett Lake17TPK08776070004987000Non-federal land
Barrett Lake17TPK08876080004987000Non-federal land
Medora Lake Road Fen17TPK09606060004990000Non-federal land
Medora Lake Road Fen17TPK09616060004991000Non-federal land
Medora Lake Road Fen17TPK09706070004990000Non-federal land
Medora Lake Road Fen17TPK09716070004991000Non-federal land
Torrance Barrens17TPK17586150004978000Non-federal land
Torrance Barrens17TPK17686160004978000Non-federal land
Torrance Barrens17TPK17696160004979000Non-federal land
Torrance Barrens17TPK17776170004977000Non-federal land
Loon Lake Bog17TPK27246220004974000Non-federal land
Loon Lake Bog17TPK27256220004975000Non-federal land
Loon Lake Bog17TPK27346230004974000Non-federal land
Loon Lake Bog17TPK27356230004975000Non-federal land
Loon Lake Bog17TPK27436240004973000Non-federal land
Loon Lake Bog17TPK27446240004974000Non-federal land
Jevins & Silver Lake Conservation Reserve17TPK37316330004971000Non-federal land
Jevins & Silver Lake Conservation Reserve17TPK37326330004972000Non-federal land
Jevins & Silver Lake Conservation Reserve17TPK37416340004971000Non-federal land
Jevins & Silver Lake Conservation Reserve17TPK37426340004972000Non-federal land
Axe Lake17TPL12676160005027000Non-federal land
Axe Lake17TPL12776170005027000Non-federal land
Total = 44 grid squares

Notes of Table 4

Note e of Table 4

Based on the standard UTM Military Grid Reference System (see URL NOT FOUND, where the first 2 digits and letter represent the UTM Zone, the following 2 letters indicate the 100 x 100 km Standardized UTM grid, followed by 2 digits to represent the 10 x 10 km Standardized UTM grid. The last 2 digits represent the 1 x 1 km Standardized UTM grid containing all or a portion of the critical habitat unit. This unique alphanumeric code is based on the methodology produced from the Breeding Bird Atlases of Canada (See Bird Studies Canada for more information on breeding bird atlases).

Return to note e referrer of table 4

Note f of Table 4

The listed coordinates are a cartographic representation of where critical habitat can be found, presented as the southwest corner of the 1 x 1 km Standardized UTM grid square that is the critical habitat unit. The coordinates are provided as a general location only.

Return to note f referrer of table 4

Note g of Table 4

Land tenure is provided as an approximation of the types of land ownership that exist at the critical habitat units and should be used for guidance purposes only. Accurate land tenure will require cross referencing critical habitat boundaries with surveyed land parcel information.

Return to note g referrer of table 4

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7.2 Activities Likely to Result in the Destruction of Critical Habitat

Understanding what constitutes destruction of critical habitat is necessary for the protection and management of critical habitat. Destruction is determined on a case by case basis. Destruction would result if part of the critical habitat was degraded, either permanently or temporarily, such that it would not serve its function when needed by the species. Destruction may result from a single activity or multiple activities at one point in time or from the cumulative effects of one or more activities over time. It should be noted that not all activities that occur in or near critical habitat are likely to cause its destruction.

Activities described in Table 5 include those likely to cause destruction of critical habitat for the species; however, destructive activities are not limited to those listed.

Table 5. Activities Likely to Destroy Critical Habitat of Branched Bartonia
Description of ActivityDescriptions of Effect in Relation to Function LossDetails of Effect
Activities that introduce or promote the establishment of exotic and/or invasive species (e.g., planting non-native species, moving fill)The introduction of invasive plant species can result in increased competition with Branched Bartonia for limited resources. Invasive species can also alter the ecological dynamics and/or cause physical and chemical changes to habitat (e.g., altered shade or soil moisture) and render it no longer suitable for Branched Bartonia. Invasive species such as Glossy Buckthorn and Common Reed spread rapidly and convert the open habitat needed by Branched Bartonia to closed habitat not suitable for the species, leading to loss of critical habitat.If this activity were to occur either within or adjacent to the bounds of critical habitat, effects would be direct and cumulative, at any time of the year. A single event within critical habitat could lead to habitat destruction because once seeds are introduced it can lead to rapid expansion of invasive species. Loss of habitat at one location could lead to loss of that local population and could compromise the long-term sustainability of the Ontario population.
Activities that result in the degradation or fragmentation of critical habitat (e.g. residential development or construction or expansion of roads, rail lines or recreational trails)Degrading habitat quality and hydrology may change critical habitat and make it unsuitable, reducing or eliminating critical habitat.If this activity were to occur within or outside the bounds of critical habitat, effects could be cumulative, or may occur from a single event, at any time of the year.
Activities that result in the alteration of natural wetland water regimes and chemistry (e.g., drainage or filling of wetlands, changes to groundwater recharge areas such as paving)As a wetland species, Branched Bartonia relies on open wet habitat, and changes to the hydrology in the wetland itself or its recharge (source) areas would degrade or destroy critical habitat.If this activity were to occur within or outside the bounds of critical habitat, effects could be cumulative, or may occur from a single event, at any time of the year. Loss of habitat at one location could lead to loss of that local population and could compromise the long-term sustainability of the Ontario population.
Operation of off-road vehicles (e.g., ATVs)Use of off-road vehicles in critical habitat could compact the substrate and make it unable to support the growth of Branched Bartonia.If this activity were to occur within the bounds of critical habitat, effects would be direct and cumulative, at any time of the year.
Activities that cause native plant removal (e.g., digging, clearing, or gathering)Removal of peat, the substrate for the wetlands comprising critical habitat, or native vegetation that contributes to suitable habitat would result in direct removal and loss of critical habitat.If this activity were to occur within the bounds of critical habitat, effects would be direct and cumulative, at any time of the year.

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8. Measuring Progress

The performance indicators presented below provide a way to define and measure progress toward achieving the population and distribution objective. Every five years, success of recovery strategy implementation will be measured against the following performance indicator:

  • The distribution and abundance of Branched Bartonia has been maintained, and where feasible, increased in Canada.

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9. Statement on Action Plans

One or more action plans will be completed for the Branched Bartonia and posted on the Species at Risk Public Registry by 2022.

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10. Effects on the Environment and Other Species

A strategic environmental assessment (SEA) is conducted on all SARA recovery planning documents, in accordance with the Cabinet Directive on the Environmental Assessment of Policy, Plan and Program Proposals. The purpose of a SEA is to incorporate environmental considerations into the development of public policies, plans, and program proposals to support environmentally sound decision-making and to evaluate whether the outcomes of a recovery planning document could affect any component of the environment or any of the Federal Sustainable Development Strategy’s (FSDS) goals and targets.

Recovery planning is intended to benefit species at risk and biodiversity in general. However, it is recognized that strategies may also inadvertently lead to environmental effects beyond the intended benefits. The planning process based on national guidelines directly incorporates consideration of all environmental effects, with a particular focus on possible impacts upon non-target species or habitats. The results of the SEA are incorporated directly into the strategy itself, but are also summarized below in this statement.

Branched Bartonia habitat is shared by many other wetland species including other rare species and species at risk. Recovery activities that conserve and/or maintain open graminoid or low shrub sphagnum wetlands will positively affect a number of other species requiring similar habitats.

Table 6. Some of the species that may benefit from conservation and management of habitat in those areas where Branched Bartonia occurs.
Common NameScientific NameSARA Status
Intermediate PinweedLechea intermediaNot at Risk
Inland SedgeCarex interiorNot at Risk
St. John’s WortTriadenum virginicumNot at Risk
White-fringed OrchidPlatanthera blephariglottisNot at Risk
Brownish BeakrushRhynchospora capitellataNot at Risk
Northern Yellow-eyed GrassXyris montanaNot at Risk
Eastern Ribbonsnake (Great Lakes population)Thamnophis sauritusSpecial Concern
Eastern Foxsnake (Great Lakes population)Pantherophis gloydiEndangered
MassassaugaSistrurus catenatusThreatened
Blanding’s Turtle (Great Lakes/St. Lawrence population)Emydoidea blandingiiThreatened

The proposed recovery activities will benefit the environment in general, and are expected to positively affect other native species. It is possible, however, that activities that control invasive shrub species may be detrimental to some species to a limited extent (e.g., cutting or uprooting may damage adjacent vegetation). Consequently, it is important that these habitat management activities for Branched Bartonia be considered carefully and all reasonable efforts to minimize such possibilities be made. It is also important that habitat management activities for Branched Bartonia be considered from an ecosystem perspective through the development, with input from responsible jurisdictions, of multi species plans, ecosystem-based recovery programs or area management plans (as appropriate) that take into account the needs of multiple species, including other species at risk.

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11. References

Brinker, S. 2006. Detailed inventory of Branched Bartonia Bartonia paniculata (Michx.) Muhlenb ssp. paniculata in Central Ontario. Prepared for Ontario Ministry of Natural Resources and Ontario Parks, 29. 61pp.

Catling, P.M. and Z.S. Porebski. 1994. The history of invasion and current status of Glossy Buckthorn, Rhamnus frangula, in southern Ontario. Canadian Field-Naturalist 108(3):305-310.

Ciotir, C., C. Yesson and J. Freeland. 2013. The evolutionary history and conservation value of disjunct Bartonia paniculata subsp. paniculata (Branched Bartonia) populations in Canada. Botany 91(9):605-613.

COSEWIC. 2003. COSEWIC Assessment and Update Status Report on the Branched Bartonia Bartonia paniculata ssp. paniculata in Canada. Committee on the Status of Endangered Wildlife in Canada. Ottawa. vi + 14pp.

Crins, William J., Paul A. Gray, Peter W.C. Uhlig, and Monique C. Wester. 2009. The Ecosystems of Ontario, Part I: Ecozones and Ecoregions. Ontario Ministry of Natural Resources, Peterborough Ontario, Inventory, Monitoring and Assessment, SIB TER IMA TR- 01, 71pp.

Cutler, G.C., Scott-Dupree, C.D., Drexler, D.M. 2014. Honey bees, neonicotinoids, and bee incident reports: the Canadian situation. Pest Management Science 70(5): 779-783.

Georgian Bay Biosphere Reserve. 2015. Accessed: October 1, 2015.

Gillett, J.M. 1959. A revision of Bartonia and Obolaria (Gentianaceae). Rhodora 61:43-62.

Health Canada. 2014. Pollinator Health and Pesticides. Website: Accessed: October 1, 2015.

Hill, S.R. 2003. Conservation Assessment for Twining Screwstem (Bartonia paniculata (Michx.) Muhl.). INHS Center for Biodiversity 2003 (7).

Higman, P.J. and M.R. Penskar. 1996. Special Plant Abstract for Bartonia paniculata (panicled screwstem). Lansing, Mighigan.

Korol, B. 2015. Personal communication to Lee Voisin. (Habitat Biologist, Canadian Wildlife Service – Ontario Region, Environment and Climate Change Canada, Toronto).

Matthews, K.G., N. Dunne, E. York and L. Struwe. 2009. A phylogenetic analysis and taxonomic revision of Bartonia (Gentianaceae: Gentianeae), based on molecular and morphological evidence. Systematic Botany 34(1):162-172.

Mazur, M.L.C., K.P. Kowalski, D. Galbraith. 2014. Assessment of suitable habitat for Phragmites australis (common reed) in the Great Lakes coastal zone. Aquatic Invasions 9(1): 1-19.

Michigan Department of Natural Resources. 2012. Invasive Species – Best Control Practices: Glossy Buckthorn (PDF, 371 KB). Michigan Natural Features Inventory. Accessed: October 1, 2015.

MNRF (Ministry of Natural Resources and Forestry). 2014. Ontario Wetland Evaluation System – Northern Manual. First Edition, Version 1.3. Toronto: Queen’s Printer for Ontario. 290 pp.

Muskoka Watershed Council. 2015. Branched Bartonia Factsheet. Muskoka Watershed Council Stewardship Guides (PDF, 743.5 KB). Accessed: October 1, 2015.

NatureServe. 2015. NatureServe Explorer: An online encyclopedia of life [web application]. Version 7.1. NatureServe, Arlington, Virginia. Accessed: August 3, 2015.

NHIC (Natural Heritage Information Centre). 2014. Element occurrence and observation report(s) for the Branched Bartonia. Peterborough (ON): Ontario Ministry of Natural Resources.

Nilsson, S.S. and J.J. Skvarla. 1969. Pollen morphology of saprophytic taxa in the Bentianaceae. Annuals of the Missouri Botanical Garden 56(3):420-438.

Ontario Ministry of Natural Resources. 2010. Natural Heritage Reference Manual for Natural Heritage Policies of the Provincial Policy Statement, 2005. Second Edition. Toronto: Queen’s Printer for Ontario. 248 pp.

Reznicek, A.A. 1994. The disjunct coastal plain flora in the Great Lake s region. Biological Conservation. 68(3):203-215.

Reznicek, A.A and R.E. Whiting. 1976. Bartonia (Gentianaceae) in Ontario. Canadian Field-Naturalist. 90(1):67-69.

Rouse, J. 2015. Personal communication via email to Talena Kraus. (Ontario Ministry of Natural Resources and Forestry, Parry Sound).

Upper Thames River Conservation Authority. 2015. Buckthorn Control Methods (PDF, 324 KB). Accessed: October 1, 2015.

van der Sluijs, J.P., N. Simon-Delso, D. Goulson, L. Maxim, J. Bonmatin, L.P. Belzunces. 2013. Neonicotinoids, bee disorders and the sustainability of pollinator services. Current Opinion in Environmental Sustainability 2013(5):293–305.

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Appendix A: Subnational Conservation Ranks of Branched Bartonia (Bartonia paniculata ssp. paniculata) in Canada and the United States
Global (G) RankNational (N) Rank (Canada)Sub-national (S) Rank (Canada)National (N) Rank (United States)Sub-national (S) Rank (United States)
G5T5N2Ontario (S2)NNRAlabama (SNR), Arkansas (S4), Connecticut (SNR), Delaware (S2), District of Columbia (SNR), Florida (SNR), Georgia (SNR), Illinois (SNR), Indiana (SNR), Kentucky (SNR), Louisiana (SNR), Maine (S1), Maryland (SNR), Massachusetts (SNR), Michigan (SNR), Mississippi (SNR), Missouri (S1), New Hampshire (S1), New Jersey (S4), New York (S1), North Carolina (S2S3), Oklahoma (SNR), Pennsylvania (SNR), Rhode Island (SNR), South Carolina (SNR), Tennessee (SNR), Texas (SNR), Virginia (S3), West Virginia (S1)

Table A-1. Ranks of Branched Bartonia in Canada and the United States. (NatureServe 2015)

Rank Definitions (NatureServe 2015)

S1: Critically Imperilled: Critically imperiled in the nation or state/province because of extreme rarity (often 5 or fewer occurrences) or because of some factor(s) such as very steep declines making it especially vulnerable to extirpation from the state/province.

S2: Imperilled: Imperiled in the nation or state/province because of rarity due to very restricted range, very few populations (often 20 or fewer), steep declines, or other factors making it very vulnerable to extirpation from the nation or state/province.

S3: Vulnerable: Vulnerable in the nation or state/province due to a restricted range, relatively few populations (often 80 or fewer), recent and widespread declines, or other factors making it vulnerable to extirpation.

S4: Apparently Secure: Uncommon but not rare; some cause for long-term concern due to declines or other factors.

S5: Secure: Common, widespread, and abundant in the nation or state/province.

SNR: Unranked: Nation or state/province conservation status not yet assessed.

S#S#: Range Rank --A numeric range rank (e.g., S2S3) is used to indicate any range of uncertainty about the status of the species or community. Ranges cannot skip more than one rank (e.g., SU is used rather than S1S4).

T#: Infraspecific Taxon (trinomial)--The status of infraspecific taxa (subspecies or varieties) are indicated by a "T-rank" following the species' global rank. Rules for assigning T-ranks follow the same principles outlined above for global conservation status ranks. For example, the global rank of a critically imperiled subspecies of an otherwise widespread and common species would be G5T1. A T-rank cannot imply the subspecies or variety is more abundant than the species as a whole-for example, a G1T2 cannot occur. A vertebrate animal population, such as those listed as distinct population segments under under the U.S. Endangered Species Act, may be considered an infraspecific taxon and assigned a T-rank; in such cases a Q is used after the T-rank to denote the taxon's informal taxonomic status.

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Footnote 1

“Populations” are characterized as being separated by >1 km (Cordeiro 2004 in NatureServe 2013).

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Footnote 2

Threatened (SARA): A wildlife species that is likely to become endangered if nothing is done to reverse the factors leading to its extirpation or extinction.

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Footnote 3

Threatened (ESA): A species that lives in the wild in Ontario, is not endangered, but is likely to become endangered if steps are not taken to address factors threatening it.

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Footnote 4

Global, national and subnational conservation ranks and their definitions are listed in Appendix A.

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Footnote 5

Seed bank: the natural storage of seeds, often dormant, within the soil. Annual plants may rely heavily on banked seeds for successful perpetuation from year to year, particularly in early successional and/or dynamic and naturally transient/patchy habitats; germination is favoured when and where ideal microhabitat conditions occur.

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Footnote 6

Obtaining nutrients from dead or decaying organic matter

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Footnote 7

Heterotrophic: reliant on organic carbon for nutrients

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Footnote 8

A species isolated from its main range along the Atlantic coast of North America. This isolated population was created as a result of glaciation (glaciers physically moving the species to a new location with suitable habitat).

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Footnote 9

These ecoregions are defined by the Ministry of Natural Resources (Crins et al. 2009).

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Footnote 10

Extent of occurrence: the area included in a polygon without concave angles that encompasses the geographic distribution of all known populations of a wildlife species (COSEWIC - Definitions and Abbreviations)

Return to footnote 10 referrer

Footnote 11

Area of Occupancy: a biological measure of the occupied habitat within a wildlife species’ range, determined by COSEWIC using an Index of Area of Occupancy (IAO).

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Footnote 12

Rescue effect: genetic or demographic immigration into a population to reduce extinction pressures

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Footnote 13

A period of 1996 to 2015 has been used to identify critical habitat in this Recovery Strategy.

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Footnote 14

Wetland boundaries as part of the Ontario Base Mapping (OBM) in northern Ontario are mapped at a 1:20,000 scale (+/- 10 m horizontal accuracy). This accuracy is within the tolerances of the OWES, but boundaries have not been field verified.

Return to footnote 14 referrer

Footnote 15

This area includes up to 120m from the Ontario Wetland Evaluation System, wetland type boundaries or habitat boundaries that can be delineated from high resolution aerial photography.

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