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Recovery Strategy for the Lakeside Daisy (Hymenoxys herbacea) in Canada [Final] 2011

Species at Risk Act Recovery Strategy Series Recovery Strategy for the Lakeside Daisy (Hymenoxys herbacea) in Canada November 2010

SARA is the Act developed by the federal government as a key contribution to the common national effort to protect and conserve species at risk in Canada. SARA came into force in 2003, and one of its purposes is "to provide for the recovery of wildlife species that are Extirpated, Endangered or Threatened as a result of human activity."

In the context of species at risk conservation, recovery is the process by which the decline of an endangered, threatened or extirpated species is arrested or reversed and threats are removed or reduced to improve the likelihood of the species' persistence in the wild. A species will be considered recovered when its long-term persistence in the wild has been secured.

A recovery strategy is a planning document that identifies what needs to be done to arrest or reverse the decline of a species. It sets goals and objectives and identifies the main areas of activities to be undertaken. Detailed planning is done at the action plan stage.

Recovery strategy development is a commitment of all provinces and territories and of three federal agencies - Environment Canada, Parks Canada Agency, and Fisheries and Oceans Canada - under the Accord for the Protection of Species at Risk. Sections 37-46 of SARA outline both the required content and the process for developing recovery strategies published in this series.

Depending on the status of the species and when it was assessed, a recovery strategy has to be developed within one to two years after the species is added to the List of Wildlife Species at Risk. Three to four years is allowed for those species that were automatically listed when SARA came into force.

In most cases, one or more action plans will be developed to define and guide implementation of the recovery strategy. Nevertheless, directions set in the recovery strategy are sufficient to begin involving communities, land users, and conservationists in recovery implementation. Cost-effective measures to prevent the reduction or loss of the species should not be postponed for lack of full scientific certainty.

This series presents the recovery strategies prepared or adopted by the federal government under SARA. New documents will be added regularly as species get listed and as strategies are updated.

To learn more about the Species at Risk Act and recovery initiatives, please consult the SARA Public Registry.

Parks Canada Agency. 2011. Recovery Strategy for the Lakeside Daisy (Hymenoxys herbacea) in Canada. Recovery Strategy Series. Parks Canada Agency, Ottawa. xi + 60 pp.

Additional copies can be downloaded from the SARA Public Registry.

Photo courtesy of Judith Jones

Également disponible en français sous le titre:
« Programme de rétablissement de l'hyménoxys herbacé (Hymenoxys herbacea) au Canada »

© Her Majesty the Queen in Right of Canada, represented by the Minister of the Environment, 2008. All rights reserved.
ISBN: 978-1-100-17324-5
Catalogue no.: En3-4/86-2011E-PDF

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

The Parks Canada Agency led the development of this federal recovery strategy, working together with the other competent minister(s) for this species under the Species at Risk Act. The Chief Executive Officer, upon recommendation of the relevant Park Superintendent(s) and Field Unit Superintendent(s), hereby approves this document indicating that Species at Risk Act requirements related to recovery strategy development (sections 37-42) have been fulfilled in accordance with the Act.

signatures


All competent ministers have approved posting of this recovery strategy on the Species at Risk Public Registry.

Under the Accord for the Protection of Species at Risk (1996), the federal, provincial, and territorial governments agreed to work together on legislation, programs, and policies to protect wildlife species at risk throughout Canada. The Species at Risk Act (S.C. 2002, c.29) (SARA) requires that the federal competent ministers prepare recovery strategies for listed Extirpated, Endangered and Threatened species.

The Minister of the Environment presents this document as the recovery strategy for Lakeside Daisy, as required under SARA. It has been prepared in cooperation with the jurisdictions responsible for the species, as described in the Preface. The Minister invites other jurisdictions and organizations that may be involved in recovering the species to use this recovery strategy as advice to guide their actions.

The goals, objectives, and recovery approaches identified in the strategy are based on the best existing knowledge and are subject to modifications resulting from new findings and revised objectives.

This recovery strategy will be the basis for one or more action plans that will provide further details regarding measures to be taken to support protection and recovery of the species. Success in the recovery of this species depends on the commitment and cooperation of many different constituencies that will be involved in implementing the actions identified in this strategy. In the spirit of the Accord for the Protection of Species at Risk, all Canadians are invited to join in supporting and implementing this strategy for the benefit of the species and of Canadian society as a whole. The Minister of the Environment will report on progress within five years.

Parks Canada Agency led the development of the recovery strategy. The strategy was prepared by J.A. Jones and J.V. Jalava for the Bruce Peninsula and Manitoulin Island Alvar1 Recovery Team, largely during the period in which Brian Hutchinson and Hilary Gignac chaired the recovery team (2002-2006). Their work in directing the team through the production of this strategy is greatly appreciated. Thanks are also due to past chair Kirsten Querbach and past team members Paul Biscaia, Eric Cobb, Talena Kraus and Holly Simpson.

1 "Alvar" is a Swedish word, originally used for the grasslands on the islands of Öland and Göteland in the Baltic Sea. In the Great Lakes basin, "alvar" refers to naturally open areas with shallow soils over relatively flat, limestone bedrock, with trees absent or at least not forming a continuous canopy (Reschke et al. 1999, Brownell and Riley 2000). There are several different kinds of alvars (just as there are different kinds of forests), and each type has a distinctive group of species present.

A strategic environmental assessment (SEA) is conducted on all SARA recovery strategies, in accordance with the Cabinet Directive on the Environmental Assessment of Policy, Plan and Program Proposals. Recovery planning is intended to benefit species at risk and biodiversity in general. However, it is recognized that strategies and action plans may also inadvertently lead to environmental effects beyond the intended benefits. The results of the SEA are summarized below and briefly outline the potential positive and negative environmental impacts as a result of the proposed recovery strategy, and resultant mitigation.

Most threats to Lakeside Daisy (Hymenoxys herbacea) are threats to its alvar habitat. Thus, the steps proposed in this recovery strategy are intended to positively impact the alvar ecosystem as a whole and to benefit the other species that occupy the habitat as well as. First and foremost, the broad strategy in this document is to protect remaining high quality examples of alvar. Much good alvar still exists in the Bruce Peninsula and Manitoulin Regions, so rehabilitation of degraded sites is of lower priority. Therefore, recovery activities for the most part will be fairly non-intrusive, allowing natural ecological processes to carry on. Future actions proposed in this recovery strategy involve communication and education, protection, management and stewardship, policy and legislation, inventory and monitoring, and research.

Specific examples of positive effects include:

The proposed activities have almost no potential for negative environmental impacts other than the possibility of a small amount of trampling from foot traffic during research and monitoring. Researchers carrying out field studies in alvar habitat need to be cautioned on the potential problem and instructed how to prevent creating such impacts.

It is not anticipated that fire will be used as a management tool in the habitat of Lakeside Daisy in the foreseeable future. Most steps in this strategy deal with engaging the public and with protecting existing high quality occurrences rather than with restoring degraded areas. It is known that some alvars have burned, but there has been almost no recent burning (in the last 50 years). Therefore, the use of burning is not a priority for management. If research on fire as a management tool is undertaken, a separate environmental assessment would need to be done.

Placement of barriers such as boulders or gates may have a small amount of impact depending on the kinds of construction techniques used. Use of heavy machinery to place boulders as barriers can be done from existing trails during dry conditions to minimize soil displacement. It is expected that signage, gates, and fencing would be placed outside the habitat in transitional areas that are less sensitive to disturbance. For example, signage to alert visitors to the sensitivity of an area and to keep hikers on trails would be located before entering the habitat, in places where there is enough soil to anchor signage in the ground or on bedrock or other ground that is already disturbed. Barriers and signage will not be placed in high quality alvar habitat.

This recovery strategy addresses the recovery of Lakeside Daisy. In Canada, this species is only found in the Bruce Peninsula and Manitoulin Island Region of Ontario.

The Parks Canada Agency and the Ontario Ministry of Natural Resources cooperatively led the development of this recovery strategy, with the members of the Bruce Peninsula and Manitoulin Island Alvar Recovery Team, and in cooperation and consultation with the Canadian Wildlife Service - Ontario Region, stakeholders, and private landowners. All responsible jurisdictions reviewed and supported posting of the strategy. The proposed recovery strategy meets SARA requirements in terms of content and process (Sections 39-41) and fulfills commitments of all jurisdictions for recovery planning under the Accord for the Protection of Species at Risk in Canada.

SARA defines residence as: a dwelling-place, such as a den, nest or other similar area or place, that is occupied or habitually occupied by one or more individuals during all or part of their life cycles, including breeding, rearing, staging, wintering, feeding or hibernating [Subsection 2(1)]. The concept of residence under the Species at Risk Act (SARA) does not apply to this species. Residence descriptions, or the rationale for why the residence concept does not apply to a given species, are posted on the SARA public registry.

Lakeside Daisy is listed as Threatened under Schedule 1 of the federal Species at Risk Act (SARA). In Ontario, it is listed as Threatened on the Species at Risk in Ontario (SARO) List under the Endangered Species Act, 2007 (ESA). The global range of Lakeside Daisy is restricted to the Bruce Peninsula and Manitoulin Island Regions of Ontario and six sites in the United States, some of which are re-introductions. The Canadian range of Lakeside Daisy accounts for 95% or more of the global population.

Lakeside Daisy is a low-growing herbaceous perennial consisting of small, leafy rosettes connected by rhizomes. Plants bloom in early May to early July with a yellow daisy-like head on a short stalk. Lakeside Daisy is only found on alvars and limestone bedrock shorelines. Alvars are naturally open areas, dominated by native grasses or sedges or low shrubs, with extremely shallow soil over limestone bedrock. They experience extremes of drought, flooding, temperature, and light levels. Some alvars that support Lakeside Daisy are known to have burned in the past, but others have no evidence of burning at all. The alvars of the Bruce Peninsula and Manitoulin Island Regions contain an exceptional variety of globally and provincially rare vegetation types and species. All alvars in Ontario are considered globally, nationally and provincially imperiled.

The main threats to Lakeside Daisy are threats to its alvar habitat. The principal threats are: off-road vehicles, building and road construction, trampling by pedestrians, quarrying, logging in adjacent forests, invasion by exotic species, and heavy machinery. As well, filling in of habitat due to fire suppression, and changes in lake levels, may affect habitat over very long time frames. Severity of threats is presented for each site.

Lakeside Daisy is found at nine sites on the Bruce Peninsula and 20 sites on the south shore of Manitoulin Island or surrounding islands. At some of the sites where it occurs, Lakeside Daisy can be abundant or even dominant. Current population trends are unknown due to lack of monitoring information.

Recovery is considered feasible for Lakeside Daisy. The goal is to maintain long-term, self-sustaining, viable populations of Lakeside Daisy in its current range in Ontario, by meeting population and distribution objectives targeted to recover the species to Special Concern or lower. The population and distribution objectives for Lakeside Daisy are 1) Prevent an overall, continuous decline in the number of populations in each of the two core areas the species occupies, and 2) Maintain the species' range at its current index of area of occupancy (114 km2) and current extent of occurrence (2,340 km2).

In total, 12 critical habitat polygons are identified at 9 sites on the Bruce Peninsula and 46 polygons are identified at 9 sites in the Manitoulin Region. This critical habitat achieves substantive progress toward fulfilling the population and distribution objectives identified in the strategy. Other recovery tools will be used to meet the objectives, and these will be achieved through implementation of the broad strategies and approaches - - primarily protection of existing populations, reduction of threats to habitat, promoting site stewardship, and public education. One or more action plans will be completed by December 2015.

Recovery of Lakeside Daisy in Canada is considered feasible based on the criteria outlined by the Government of Canada (2009):

  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; biologically, this species has many large, self-sustaining populations and sites where abundant or even dense growth of plants is present. There are sufficient numbers to improve population sizes when adequate habitat is present and threats are not present. Biological factors are probably not the main limitations for this species.

  2. Sufficient suitable habitat is available to support the species or could be made available through habitat management or restoration.
    Yes; the habitat of Lakeside Daisy has been shown to change very slowly over long periods of time (50-200 years). Large areas of high quality, intact alvar habitat still exist, with several now in protected areas.

  3. The primary threats to the species or its habitat (including threats outside Canada) can be avoided or mitigated.
    Yes; many threats can be avoided or mitigated through communications actions to increase awareness about the species, liaising with other groups and agencies, erecting signage, working with management of protected areas, and many other steps.

  4. Recovery techniques exist to achieve the population and distribution objectives or can be expected to be developed within a reasonable timeframe.
    Yes; the Nature Conservancy's International Alvar Initiative (IACI) (Reschke et al. 1999) initiated recovery of alvar ecosystems and associated rare species, and experiences from the IACL show these techniques can be very effective.

Date of Assessment: May 2002

Scientific Name: Hymenoxys herbacea (E.L. Greene) Cusick

COSEWIC Status: Threatened

Canadian Occurrence: Ontario

Reason for Designation: A Great Lakes endemic of global importance, geographically restricted to two shoreline regions of very restricted and provincially rare alvar habitats with large populations subject to risks from natural herbivores and increasing recreational use of its habitat.

COSEWIC Status History: Designated Threatened in May 2002. Assessment based on a new status report.

Lakeside Daisy is listed as Threatened and is on Schedule 1 of the federal Species at Risk Act (SARA). In Ontario it is listed as Threatened on the Species at Risk in Ontario (SARO) List under the Endangered Species Act, 2007 (ESA). The global rank of Lakeside Daisy is G3 or Vulnerable (NatureServe 2009). It is currently listed as S1 or Critically Imperiled in Illinois, Michigan, and Ohio, and S3 or Vulnerable in Ontario. The species is federally listed as Threatened in the United States. The global range of Lakeside Daisy is completely restricted to the Bruce Peninsula and Manitoulin Island Regions of Ontario and six sites in the United States, some of which are re-introductions (NatureServe 2009). The Canadian range of Lakeside Daisy probably accounts for 95% or more of the global population. See Section 2.1 Populations and Distribution Context.

Also called "Stemless Rubberweed" on the Bruce Peninsula or "Manitoulin Gold" on Manitoulin Island (Morton and Venn 2000), the name Lakeside Daisy is derived from its occurrence at Lakeside, Ohio. The plant is a low-growing herbaceous perennial consisting of several small, leafy rosettes connected by rhizomes. The leaves are dark green and faintly hairy. Floral buds form in the fall and rosettes persist through the winter, allowing the plant to bloom in early spring, starting in early May and continuing in some areas to early July (COSEWIC 2002). The inflorescence is a yellow daisy-like head on a short stalk (5-15 cm) that elongates somewhat during fruit set and dispersal.

Lakeside Daisy could be confused with Lance-leaved Tickseed (Coreopsis lanceolata), a similar yellow-orange, daisy-like flower found on some alvars. However, Lakeside Daisy has faintly hairy (vs. smooth, somewhat shiny) leaves, a short, sturdy (vs. tall, slender) stalk, and yellow (vs. yellow-orange) ray flowers. Also, Lakeside Daisy tends to bloom earlier (early May to early July vs. mid-June to mid-July) and is entirely restricted to alvars on dolostone, whereas Lance-leaved Tickseed also occurs in other open habitats.

Lakeside Daisy is only found on alvars and on limestone bedrock shorelines similar to alvars. The alvars of the Bruce Peninsula and Manitoulin Island Regions in Ontario are internationally recognized for their rarity, their distinct ecological character, and for their exceptional variety of globally and provincially rare vegetation types and species. Many of these species are endemic, occurring only in the Great Lakes basin, and some only occur on alvars. A list of rare alvar species is given in Appendix A. All alvars are considered globally, nationally and provincially threatened (NatureServe 2009; NHIC 2009). Because most threats to Lakeside Daisy stem from impacts to its highly threatened alvar habitat, and because of the hugely significant biodiversity on alvars, recovery of Lakeside Daisy will be most effective if undertaken within an ecosystem-based approach.

Alvars are unusual for a number of reasons. They are naturally open areas in an overall forested landscape. The dominant plants are usually native grasses, sedges or low shrubs. Alvars have extremely shallow soil and experience extremes of drought and flooding, temperature, and light levels (Reschke et al. 1999). Some alvars are relict habitats that have existed since the post-glacial era, while others originated from fires, either a catastrophic event, or periodic smaller fires (Jones and Reschke 2005). Alvars contain many species that normally live in other regions such as boreal and prairie biomes (Catling 1995; Catling and Brownell 1993). As well, some alvars support ancient, stunted trees more than 400 years old (Schaefer and Larson 1997).

Lakeside Daisy grows on alvars and limestone shores, in shallow cracks or crevices in open, exposed bedrock in a few centimetres of sand or accumulated organic soil, or sometimes in small patches of sand on top of bedrock (Figure 1). It occurs only on Silurian dolostone. Sites are generally dominated by Little Bluestem (Schizachyrium scoparium), Northern Dropseed (Sporobolus heterolepis), Creeping Juniper (Juniperus horizontalis), or by Lakeside Daisy itself. There are few populations in dense grasslands (where there is no bare bedrock) or in treed areas. In the Manitoulin Region, all but 3 of the 20 occurrences are within 500m of the Lake Huron shore. On the Bruce Peninsula, 4 of the 9 occurrences are inland and therefore at higher elevations.

Figure 1. Alvar at Ontario Nature's Bruce Alvar Nature Reserve with Lakeside Daisy in the Foreground

Figure 1. Alvar at Ontario Nature's Bruce Alvar Nature Reserve with Lakeside Daisy in the Foreground

A number of ecological processes define alvars and possibly maintain them in their open state, and any of these may be a requirement in the habitat of Lakeside Daisy. Alvars typically have very shallow soils (usually 0 to about 20 cm) that provide little water-holding capacity and dry out quickly. The bedrock below permits little drainage after rainfall, causing frequent and rapid flooding. As a result, alvars fluctuate between conditions of flooding and extreme drought. Also, the lack of tree cover and exposed bedrock contribute to high levels of light and wind, as well as temperature extremes, with surface temperatures reaching as high as 53°C in summer (Schaefer and Larson 1997). Hence, most alvar species are assumed to be drought-adapted. Compared to some types of alvar, the habitat of Lakeside Daisy generally has a lot of exposed rock surface and shallower soil layers, making the effects of natural ecological processes most pronounced. Even in winter under snow, the blackish surface of the bedrock absorbs heat from sunlight and radiates enough warmth to slowly melt snow.

It is not clear whether Lakeside Daisy directly requires fire, but the openness of the habitat where it occurs may be the result of past fire. Some alvars that support Lakeside Daisy are known to have burned in the past, but others have no burn evidence at all (Jones and Reschke 2005). It has been speculated that alvars in the no-burn category originated in post-glacial times and are becoming vegetated at an extremely slow rate (in the order of centuries) (Jones and Reschke 2005), or that the drought-flood cycle and shallow soils perpetually inhibit growth of woody vegetation.

Flowers of Lakeside Daisy cannot self-pollinate and require insect pollination. Campbell (2001) studied 13 populations of Lakeside Daisy on the Bruce Peninsula and observed that the flowers were visited by at least 41 different taxa of insects from eight different families, although probably not all of them accomplished pollination. The most prevalent visitors were flies; however, additional researchers (DeMauro 1993, Bouchard pers. comm. 1996) suggest that bees are more important pollinators.

Seeds are dispersed by gravity or wind. There is no period of seed dormancy, and new seedlings may appear in late summer (COSEWIC 2002). The species also reproduces vegetatively by rhizomatous growth or branching of the woody caudex. The prevalence of sexual or vegetative reproduction varies from year to year. Campbell (2001) found that 23% of plants reproduced asexually, while 12-24% of plants reproduced sexually during a one year period. In addition, not all fertilized ovaries set fruit-only an average of 42.6% of seeds per inflorescence was produced. Campbell notes as well that in spite of these results, the plants do not appear to suffer pollen limitation. The reason for the low seed set is unknown.

The main threats to Lakeside Daisy are threats to the alvar ecosystems that are its habitat. Threats were not examined in detail in the COSEWIC Status Report (COSEWIC 2002). Based on more recent background information (NHIC 2009, Jalava 2008, Jalava 2004a, Oldham and Kraus 2002, Brownell and Riley 2000), as well as the direct observations of the authors and recovery team members, the principal anthropogenic stresses affecting Lakeside Daisy and alvar habitats are: off-road vehicle use, building and road construction, trampling by pedestrians, quarrying, logging in adjacent forests, invasion by exotic species, and heavy machinery. Herbivory is noted as an impact to the species in the COSEWIC report (2002), but recent field studies have not corroborated this. As well, genetic isolation is a potential but unstudied threat, and filling in of habitat due to fire suppression, changes in lake levels, and changes in climate, may potentially be affecting habitat over very long time frames. Threats are presented on a site-by-site basis in Table 1. Only those threats that are current and have a high degree of causal certainty and level of concern are presented. Potential and future threats are described in the text below.

Off-road Vehicles: Alvars, with their open aspect, are appealing to off-road vehicles, and their use is a serious concern, especially as all-terrain vehicles (ATVs) are nearly unrestricted in their movements and do not require trails or roads. ATVs disturb or destroy vegetation, displace shallow layers of soil, leave ruts, and are vectors for invasive species. ATV use is an increasingly popular recreational pastime, and the threat is widespread. Damage to habitat and uprooting of plants by ATVs on the extremely sensitive alvar pavement (i.e., areas of bare dolostone bedrock) is a serious, widespread threat to Lakeside Daisy populations, especially where populations are adjacent to shoreline areas that are public rights-of-way.

Table 1: Threats to Lakeside Daisy by Site.
Legend: X - Current major impact; x - Current minor impact; H - Historical impact. Threats sources: Brownell and Riley (2000); NHIC (2009); COSEWIC (2002); McGuire (2006); and direct observations by the authors or Recovery Team members.

Site Name Off-road vehicles Bldg. & road development Pedestrian trampling Quarrying Adjacent logging Exotic Species Heavy Machinery
BRUCE PENINSULA
Cabot Head PNR x x H x
Dyer's Bay Rd (incl Bruce Alvar NR) x
Emmett Lake Road X x x H x
South of George Lake
George Lake X x
Halfway Log Dump / Cave Point x X
West of Cave Point X
Grotto / Overhanging Rock Point X
East of Nawash Hunting Grounds x x
MANITOULIN REGION
Belanger Bay X H
Black Point - Fisher Bay
Burnt Island Harbour, NW of Burnt Island Harbour, Christina Bay X
Burnt Island Road
Carroll Wood Bay X x
Gatacre Point (E. Taskerville)
Greene Island
Lorne Lake (Taskerville inland)
Lynn Bay
West of Lynn Point X x x
Misery Bay E. X H x
Misery Bay W. x x x H x
Mississagi Lighthouse X X x
Murphy Point (Macs Bay) x H x
Quarry Bay X H x
Rickley Harbour/Girouard Pt.
West of Sand Bay
Silver Lake S. of Hwy 540 x
Silverwater Radio Towers
Taskerville - Portage Point

Building and Road Construction: Alvars are prime sites for seasonal or permanent residential development because of their proximity to the Lake Huron shoreline. Alvar habitat may be entirely eliminated by the construction of buildings, yards, driveways, and roads. Associated impacts include: clearing of alvar vegetation; blasting of bedrock for basements, trucking-in of fill that may introduce invasive, non-native plants; trampling of vegetation; and displacement of shallow soils (leaving ruts) by heavy machinery. Several remote sites for Lakeside Daisy have no current impacts (hence they are not represented in the Table above), but could be subdivided and developed in the future.

Trampling by Pedestrians: High visitor use and the resulting foot traffic at some alvars threatens the vegetation and sensitive species. In addition, unmonitored camping activities (putting tents, fire pits, and latrines on alvar) threaten some sites. On the Bruce Peninsula, recreational foot traffic is a threat to Lakeside Daisy shoreline occurrences (COSEWIC 2002). Signage, designated trails and boardwalks (at Ontario Nature's Bruce Alvar Nature Reserve), and relative inaccessibility (Cabot Head and Emmet Lake sites) currently reduce the threat of serious impacts at some locations.

Quarrying: Alvars are prime sites for quarry development because the limestone or dolostone bedrock is close to the surface and little clearing of forest and overlying soil is necessary. Aggregate extraction can completely destroy Lakeside Daisy habitat. On western Manitoulin Island a large area of alvar will be affected by expansion of the largest quarry in Ontario. At present, no significant alvar sites on the Bruce Peninsula are believed to be threatened by quarrying.

Logging: Use of heavy machinery for logging in forests adjacent to alvars and Lakeside Daisy habitat is a frequent and widespread threat. Logging damages alvar habitats when roads are built across alvars or when alvars are used as log landings and loading grounds. This has occurred at several alvars on western Manitoulin Island and could occur again in almost any alvar on private land.

Invasion by Exotic Species: Invasion by non-native species is one of the most serious effects of human disturbance at alvar sites. Exotic species compete with native species for rooting space and for scarce nutrients and moisture, frequently leading to reduction or extirpation of native species (Stephenson 1995; Jones 2000). Invasion by exotic species is often associated with other human-caused disturbances such as road building. Some examples of problem exotics include Common St. John's Wort (Hypericum perforatum), Mossy Stonecrop (Sedum acre), Canada Bluegrass (Poa compressa), and White Sweet Clover (Melilotus alba) (Reschke et al. 1999).

Heavy Machinery: Use of heavy machinery to remove boulders, stones, and granitic erratics for sale to the landscaping industry also destroys vegetation and displaces shallow soils. The boulders, stones, and erratics themselves have functions within the ecosystem that have not been studied. They may be important in providing small patches of shade, trapping organic matter, supporting numerous lichen species, blocking the wind, or performing other possible functions. Ornamental stone removal has become more common on the Bruce Peninsula recently.

Filling in of Habitat Due to Fire Suppression: It is evident that wildfire occurred during the past 150 years at many alvars in the Bruce and Manitoulin Regions (Schaefer 1996, Schaefer and Larson 1997, Jones and Reschke 2005), and some habitat for Lakeside Daisy was probably created by fire (Jones and Reschke 2005). Filling in of habitat, possibly from fire suppression, may result in the reduction or elimination of Lakeside Daisy habitat over the long term and thus is a threat to the species. However, because the time frame over which this happens is long, and because Lakeside Daisy sites are at different stages of succession, it is difficult to gauge the effects or urgency of this potential threat. The time frame over which this threat may act, and thus the urgency of addressing it, is unknown.

Changes in Lake Levels: Changes in lake levels affect shoreline populations of Lakeside Daisy. Flooding, wave-wash, and ice-scour may play a role in the perpetuation of the bedrock shoreline habitat of Lakeside Daisy, but at higher lake levels the size or presence of some of these habitats and populations becomes reduced. It is assumed that historically, the species was able to respond to and recover from changes in the natural cycle of lake levels. However, with human controlled out-flow rates (Derecki 1985) and potential diversion of water from Lakes Huron and Michigan, it is not certain that the natural lake level cycles will continue, and this may be a potential threat.

In order to plan recovery of Lakeside Daisy, it is important to see the work that has already been done to avoid duplication of efforts. Much work to protect alvars and increase awareness of their significance pre-dated this recovery strategy. Many of these actions have directly protected or otherwise benefited Lakeside Daisy populations. Some of the major accomplishments include:

Bruce Peninsula and Manitoulin Region Alvar Surveys (2004-2008): A number of previously unsurveyed alvar sites in the Bruce Peninsula (Jalava 2004a, 2006, 2007, 2008) and Manitoulin Regions (Jones 2004-2008) were inventoried and mapped during 2004-2008 to support this recovery strategy and work towards identification of critical habitat for Lakeside Daisy.

First Nations Species at Risk (SAR) Inventory and Mapping: During the summers of 2007-2009, two First Nations in the Bruce Peninsula and Manitoulin Region undertook inventories (e.g. Jones 2007) that included alvars and Lakeside Daisy. This is the first step towards recognizing the presence and needs of these species on First Nations lands.

International Alvar Conservation Initiative (IACI) The IACI, coordinated by The Nature Conservancy, Chicago, IL, studied alvars across North America (Reschke et al. 1999) and produced detailed field inventories and mapping of Lakeside Daisy occurrences. The IACI culminated with a workshop on North American alvars held in June 1998, involving approximately 100 participants. The IACI led to many subsequent alvar conservation activities in Ontario (some described next).

The Ontario Alvar Theme Study: An ecological theme study of Ontario alvars (Brownell and Riley 2000) was produced by Ontario Nature. This project looked at alvars in Ontario, collected additional field data, ranked sites, and made recommendations on the significance and conservation status of alvars across the province. Lakeside Daisy was used as one of the elements on which the ranking was based.

Alvar Stewardship Packages: As part of the IACI, stewardship information packages were distributed to private landowners of alvars in the Manitoulin Region (Jones 1998) as well as in other parts of Ontario (Jalava 1998).

Public Awareness and Consultation: A considerable amount of public contact and education about alvars has already occurred, mostly due to the IACI. Contact was made with many alvar landowners when permission was sought to survey their lands for the IACI. This was followed up with stewardship packages given to many of these landowners. The word "alvar" has become a familiar term in common usage in the Bruce Peninsula and Manitoulin Region. The aggregate industry has been informed about alvars, and the Aggregate Producers Association of Ontario has featured alvars in their annual reports several times (Ontario Aggregate Resources Corporation 2009). These efforts have resulted in increased awareness of Lakeside Daisy.

Protected Areas Management: At Bruce Peninsula National Park, Misery Bay Provincial Nature Reserve, and private nature reserves such as the Bruce Alvar Nature Reserve, management has focused on maintaining the integrity of Lakeside Daisy habitat and Lakeside Daisy populations. This has resulted in routing trails away from sensitive areas and construction of boardwalks.

Lands Protected: Several key alvars have been protected in the last 10 years either by being acquired by private land trusts or incorporated into provincial or national parks, or other protected areas. At present, 18 of 29 Lakeside Daisy sites are found wholly or in part within protected areas (see Section 2.5).

This section summarizes important knowledge gaps for Lakeside Daisy and alvar ecosystems in the Bruce and Manitoulin Regions.

Land use and threats analysis: A comprehensive look at current threats and current and proposed land uses in and adjacent to Lakeside Daisy sites is needed to assess likely impacts and help focus conservation and site stewardship activities.

Information on alvar ecology to inform better management of Lakeside Daisy habitat: Although some recent studies of the natural processes that create and maintain alvars have been undertaken (e.g., Gilman 1995, Schaefer and Larson 1997, Catling and Brownell 1998, Jones and Reschke 2005), many unanswered questions remain. The ecological role of wildfire, flooding, drought, and other factors need to be better understood if long term management and stewardship of alvars are to be successful.

The need for fire: The use of controlled burning to maintain habitat needs to be studied.

Monitoring change: How are alvars changing due to threats, or due to natural succession, and how quickly?

Exotic and invasive species: An understanding of the status, impacts, and control of exotic and invasive species in alvars would be useful to land managers so as to better control and reduce the impacts of this identified threat.

Genetic Isolation: This may be a potential threat to this geographically-restricted species. However, Esselman et al. (2000) examined genetic diversity among Lakeside Daisy populations and found the species had a genetic diversity comparable to other outcrossing endemic species, with a greater diversity within populations than among separate locations. Still, for populations consisting of very small isolated patches (e.g. several inland locations on Western Manitoulin), genetic isolation may limit the species ability to respond to changing conditions. The effects of this potential threat need further study.

Changes in Climate: As an alvar-obligate species, Lakeside Daisy already endures extreme levels of heat and drought. It is not known what Lakeside Daisy's limits of temperature and drought tolerance might be.

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2025-08-28