Gray ratsnake (Pantherophis spiloides) proposed recovery strategy 2017: chapter 1

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Part 1 – Federal Addition to the Recovery Strategy for the Gray Ratsnake (Pantherophis spiloides) – Carolinian and Frontenac Axis populations in Ontario, prepared by Environment and Climate Change Canada.

Preface

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 and Minister responsible for the Parks Canada Agency is the competent minister under SARA for the Gray Ratsnake (Carolinian population) and the Gray Ratsnake (Great Lakes/St. Lawrence population) (henceforth referred to as the Gray Ratsnake (Carolinian and Great Lakes/St. Lawrence populations) and has prepared the federal component of this recovery strategy (Part 1), as per section 37 of SARA. SARA section 44 allows the Ministers to adopt all or part of an existing plan for the species if it meets the requirements under SARA for content (sub-sections 41(1) or (2)). A single document has been prepared to address the recovery of the two Gray Ratsnake populations (Carolinian and Great Lakes/St. Lawrence) under SARA. The Ontario Ministry of Natural Resources (now the Ontario Ministry of Natural Resources and Forestry) led the development of the attached recovery strategy for the Gray Ratsnake Carolinian and Frontenac Axis populations (Part 2) in cooperation with Environment and Climate Change Canada and the Parks Canada Agency. In this federal addition, “Frontenac Axis population” has been replaced by the term “Great Lakes/St. Lawrence population” because of how the species is listed under SARA, and these terms may be used interchangeably. The Province of Ontario also led the development of the attached Government Response Statement (Part 3), which is the Ontario Government’s policy response to its provincial recovery strategy and summarizes the prioritized actions that the Ontario Government intends to take and support.

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, the Parks Canada Agency, or any other jurisdiction alone. All Canadians are invited to join in supporting and implementing this strategy for the benefit of the Gray Ratsnake (Carolinian and Great Lakes/St. Lawrence populations) 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, the Parks Canada Agency 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, SARA requires that critical habitat then be protected.

In the case of critical habitat identified for terrestrial species including migratory birds SARA requires that critical habitat identified in a federally protected area^Footnotei be described in the Canada Gazette within 90 days after the recovery strategy or action plan that identified the critical habitat is included in the public registry. A prohibition against destruction of critical habitat under ss. 58(1) will apply 90 days after the description of the critical habitat is published in the Canada Gazette.

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.

If the critical habitat for a migratory bird is not within a federal protected area and is not on federal land, within the exclusive economic zone or on the continental shelf of Canada, the prohibition against destruction can only apply to those portions of the critical habitat that are habitat to which the Migratory Birds Convention Act, 1994 applies as per SARA ss. 58(5.1) and ss. 58(5.2).

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.

Acknowledgements

The initial draft of the federal addition was prepared Talena Kraus (Artemis Eco-Works). Additional preparation and review was completed by Megan Eplett (formerly Environment and Climate Change Canada, Canadian Wildlife Service – Ontario), Ken Tuininga, Lauren Strybos, Angela Darwin and Krista Holmes (Environment and Climate Change Canada, Canadian Wildlife Service – Ontario). Lesley Dunn, Liz Sauer and Elizabeth Rezek (Environment and Climate Change Canada, Canadian Wildlife Service – Ontario), Vivian  Brownell, Joe Crowley, Jay Fitzsimmons  and Anita Imrie (Ontario Ministry of Natural Resources and Forestry) and Sheldon Lambert, Prabir Roy, Joanne Tuckwell (Parks Canada Agency) reviewed and provided comments and advice during the development of this document.

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, landowners, citizens and stakeholders who provided input and/or participated in consultation meetings.

Additions and modifications to the adopted document

The following sections have been included to address specific requirements of the federal Species at Risk Act (SARA) that are not addressed in the Recovery Strategy for the Gray Ratsnake (Pantherophis spiloides) – Carolinian and Frontenac Axis populations in Ontario (Part 2 of this document, referred to henceforth as “the provincial recovery strategy”) and/or to provide updated or additional information. 

Environment and Climate Change Canada is adopting the provincial recovery strategy (Part 2) with the exception of section 2, Recovery. In place of section 2, Environment and Climate Change Canada has established its own population and distribution objectives that are consistent with the provincial recovery goal, and is adopting the government-led and government-supported actions of the Gray Ratsnake – Carolinian and Frontenac Axis Populations – Ontario Government Response Statement^Footnote1 (Part 3) as broad strategies and general approaches to meet the population and distribution objectives, and is adopting the habitat regulated under Ontario’s Endangered Species Act, 2007 (ESA) as critical habitat for the Gray Ratsnake (Carolinian and Great Lakes/St. Lawrence populations).

Under SARA, there are specific requirements and processes set out regarding the protection of critical habitat. Therefore, statements in the provincial recovery strategy referring to protection of the species’ habitat may not directly correspond to federal requirements. Recovery measures dealing with the protection of habitat are adopted; however, whether these measures will result in protection of critical habitat under SARA will be assessed following publication of the final federal recovery strategy.

1. 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 the Gray Ratsnake (Carolinian and Great Lakes/St. Lawrence populations). 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 (Great Lakes/St. Lawrence). This population has been estimated to contain 25,000 – 85,000 individuals, and includes adult males and females known to reproduce as well as juveniles and neonates ^Footnote2 (COSEWIC 2007). However, an increase in road development has been observed throughout this region, leading to an increase in individuals, particularly females, lost to road mortality, which may have significant effects on the population as a whole (COSEWIC 2007; Kraus et al. 2010). 

Unknown (Carolinian). Due to the secretive nature of these snakes and a lack of demographic ^Footnote3 sampling in this region, the size of this population, and its structure, are unknown. There are four subpopulations within the Carolinian region, known as Big Creek, Oriskany Sandstone, Skunk’s Misery and Niagara (COSEWIC 2007; Kraus et al. 2010). These subpopulations are highly isolated and appear to be quite small, though exact numbers are unknown. During a study of one subpopulation, two snakes were tracked and another was found dead on a road, but no others were found despite efforts made to search for them (Yagi and Tervo 2006). Based on the amount of suitable habitat available and the few observations of individuals, this population may also be threatened by negative genetic effects of small population size and demographic stochasticity ^Footnote4, as well as numerous other threats.

While most of the range of this species is in the United States, both the Great Lakes/St. Lawrence and Carolinian populations are genetically distinct and geographically isolated from the populations found in continuous portions of this range, with the exception of a small portion of the Great Lakes/St. Lawrence population which extends into upper New York State. Although immigration of individuals from this portion of the population into the Canadian portion of the Great Lakes/St. Lawrence population may be possible, rescue ^Footnote5 is unlikely to occur as Highway 401 and the St. Lawrence River are significant barriers to movement (COSEWIC 2007). Additionally, more information regarding population persistence is needed to determine how many individuals are required to sustain a viable population of Gray Ratsnake, as this is currently unknown.

2. Sufficient suitable habitat is available to support the species or could be made available through habitat management or restoration.

Yes (Great Lakes/St. Lawrence). Suitable habitat for the Gray Ratsnake consists of a broad range of habitat types, including forests, forest edges, old fields, meadows, rocky outcrops and marshes (Blouin-Demers and Weatherhead 2001a, b, c, and 2002b). There is currently sufficient suitable habitat available to support this population. The regeneration of forest habitat across the region may result in an increase of suitable habitat for the species, although some habitat loss is irreversible and the expansion of road networks continues to fragment habitats. There has also been an increase in residential development within this population’s range, particularly for cottages and recreational activities. Although it is unlikely that additional land will be cleared for agriculture, there is a high possibility that it will be cleared for housing or recreational development, which will likely reduce and fragment the habitat further. It is not known at what threshold there would no longer be sufficient habitat to support the population, but given recent genetic studies it is unlikely that the population could withstand much habitat loss and still remain self-sustaining (Prior et al. 1997; Howes et al. 2009).

Unknown (Carolinian). Much of the suitable habitat for this population has already been irreversibly lost or is highly fragmented due to agricultural and urban development as well as high road density, and it is unknown whether the remaining existing habitat will be sufficient to support a self-sustaining population (COSEWIC 2007), whether or not habitat management or restoration occurs to increase suitable habitat. Gray Ratsnakes require relatively large areas of habitat in a mosaic ^Footnote6 of forest and open areas due to their large home ranges and ability to travel long distances from their hibernacula ^Footnote7 as well as to maintain connectivity and facilitate gene flow between existing subpopulations (Weatherhead and Charland 1985; Blouin-Demers and Weatherhead 2001a and b; Blouin-Demers and Weatherhead 2002a; COSEWIC 2007).

3. The primary threats to the species or its habitat (including threats outside Canada) can be avoided or mitigated.

Yes (Great Lakes/St. Lawrence). The primary threats to the Gray Ratsnake include habitat loss, degradation and fragmentation, direct mortality and road mortality, and disturbance or destruction of hibernacula. Through protection of the available habitat through legal and stewardship means (e.g., habitat protection under Ontario’s ESA and SARA, conservation easements, awareness and education campaigns such as those run by Ontario Nature, and partnerships between government and stakeholder groups such as the Lanark County property owners association), future habitat loss, degradation and fragmentation could possibly be mitigated, as could destruction of hibernacula and some direct mortality. Road mortality may be more difficult to mitigate, as common techniques such as eco-passages implemented in some parts of Ontario (i.e., Highway 69/400) have had varied levels of success (Taylor et al. 2014; Baxter-Gilbert et al. 2015). However, research on eco-passage effectiveness is growing, and approaches continue to be updated and refined. Additionally, a recent study conducted along the Thousand Islands Parkway indicates that road mortality for Gray Ratsnakes, among other snake species, was strongly linked to time of year and temperature over multiple years, which may have implications for where mitigation efforts could be focused (Garrah et al. 2015).  Additionally, Snake Fungal Disease (SFD) has been identified as a potential threat to the Gray Ratsnake in this recovery strategy as new  information has become available since the completion of the provincial recovery strategy. Methods for controlling wildlife diseases in general have been developed but have not been proven for SFD, although the spread of the disease can be mitigated through instrument decontamination if snakes are handled (Langwig et al. 2015).

Unknown (Carolinian). As with the Great Lakes/St. Lawrence population, future habitat loss, degradation and fragmentation could be mitigated through the protection and management of available habitat through legal and stewardship means, while restoration techniques could be used to increase the amount of available suitable habitat and increase connectivity between local populations where loss or fragmentation is not irreversible. Other primary threats may also be mitigated through various recovery activities; additional monitoring for hibernacula in this region could help to identify important overwintering areas requiring further protection measures, while direct mortality could be mitigated through increased education and promotion of best management practices for landowners. Habitat connectivity could also be improved through protection and management of movement habitat between known sites, though the active restoration of forest habitat is likely required to alleviate this threat. There are several ways through which the primary threats to the species and its habitat can be mitigated; however, the validity of these methods for reducing significant threats to the Carolinian population and likelihood of success is not well known. Given the small size and fragmented nature of the population, and the already relatively poor quality of the habitat, it is unknown whether recovery actions could sufficiently mitigate threats to the population or its habitat to a point where recovery would be deemed feasible. Also, similar to the Great Lakes/St. Lawrence population, SFD is also a concern for the Carolinian population.

4. Recovery techniques exist to achieve the population and distribution objectives or can be expected to be developed within a reasonable timeframe.

Unknown (Great Lakes/St. Lawrence). Stewardship, protection and education/outreach activities to address threats of accidental mortality and habitat loss and degradation exist and are being used to aid in the recovery of the species (see Section 1.8 in Part 2). Best management practices have been developed and can be communicated to provide landowners with the information necessary to coexist with the species without destroying suitable habitat (e.g., Best Management Practices such as maintaining basking areas, creating artificial nests and providing additional shelter such as cover boards, rock piles and brush and compost piles (Leeds County Stewardship Council 2008; Sciensational Sssnakes!! 2014; Ontario Species at Risk Landowner’s Guide for Black Rat Snake ^Footnote8)). While Best Management Practices are available, negative attitudes toward snakes can present challenges to implementation due to a lack of support for stewardship actions benefitting snakes (Kelly and Seidel 2015). Addressing road mortality and habitat degradation due to increased road development will be more difficult as much of this habitat alteration is irreversible or would require implementing substantial changes using techniques that have not yet been proven effective for this species. Further studies on the ecological impact of roads on snakes are being conducted, and may be useful in developing future mitigation techniques.

Unknown (Carolinian). Some habitat restoration and best management techniques exist, as do artificial nest programs for this population (COSEWIC 2007; Kraus et al. 2010). Work to further refine and encourage the application of best management practices is being conducted through increasing outreach with landowners and school boards, and educational resources and booklets are being provided to raise public awareness of the species’ recovery needs. However, in addition to the challenge of road mortality, it is not known if these techniques are sufficient to recover this population.

2. Species status information

The Gray Ratsnake (Carolinian population) is listed as Endangered^Footnote9 on Schedule 1 of the federal Species at Risk Act (SARA), while the Gray Ratsnake (Great Lakes/St. Lawrence population) is listed as Threatened^Footnote10. In Canada, Gray Ratsnakes are only found in Ontario, and occur in two regions; the Carolinian population occurs in the Carolinian forest region along the north shore of Lake Erie in southwestern Ontario, and the Great Lakes/St. Lawrence population is associated with the Frontenac Axis region in southeastern Ontario. In Ontario, the Gray Ratsnake (Carolinian population) is listed as Endangered under the provincial ESA, while the Gray Ratsnake (Frontenac Axis population^Footnote11) is listed as Threatened^Footnote12.

The Gray Ratsnake is ranked globally as Secure (G5), while the Gray Ratsnake - Carolinian population is ranked as Critically Imperilled (N1) and the Gray Ratsnake - Great Lakes/St. Lawrence population is ranked as Vulnerable (N3) in Canada (NatureServe 2015).

The Canadian distribution of this species represents less than 5% of the global range, with the majority of the Canadian population made up of the Great Lakes/St. Lawrence population (Area of Occupancy^Footnote13 < 1,500 km²) and only a small fraction occurring in the Carolinian population (Area of Occupancy 320 km²); the remainder of the species’ population is in the United States (COSEWIC 2007).

3. Threats

As described in the provincial recovery strategy (Part 2, section 1.6), habitat degradation, fragmentation and loss, direct mortality, road mortality and disturbance or destruction of hibernacula are ongoing threats to the Gray Ratsnake (Kraus et al. 2010).

In addition to those threats identified in Part 2, another potential threat that may affect the Gray Ratsnake is Snake Fungal Disease (SFD) (Ophidiomyces ophiodiicola). This is an emerging fungal disease in wild snakes that causes severe skin lesions, leading to widespread morbidity and mortality (Sleeman 2013; Allender et al. 2015). SFD is currently known to affect at least seven species including the Northern Watersnake (Nerodia sipedon sipedon), Eastern Foxsnake (Pantherophis gloydi), Eastern Milksnake (Lampropeltis triangulum), and Massasauga (Sistrurus catenatus) (Sleeman 2013). SFD has recently been confirmed in Ontario, in an Eastern Foxsnake found in southwestern Ontario in 2015 (Crowley pers. comm. 2015). It has also been confirmed in nine states in the U.S., although it is likely to be even more widespread (Sleeman 2013).

The disease spreads directly through contact with infected snakes and indirectly via environmental exposure (i.e., contact with contaminated soil) (Sleeman 2013; Allender et al. 2015).  While the population-level effects of SFD remain unclear, it appears to spread easily and is often fatal, and there is concern it could have negative impacts on small snake populations of conservation concern (Sleeman 2013; Allender et al. 2015). For example, SFD is thought to have contributed to a 50% decline in a small Timber Rattlesnake (Crotalus horridus) population in New Hampshire in 2006 to 2007 (Clark et al. 2011). Climate change has the potential to further increase the risk of SFD to snake populations, as warming temperatures may lead to increased infection rates in hibernating snakes (Allender et al. 2015). Due to the small and isolated range of the Gray Ratsnake both globally and in Canada, SFD may threaten population viability if it becomes established in the population.

4. Population and distribution objectives

The provincial recovery strategy recommended the following recovery goal for the recovery of the Gray Ratsnake in Ontario:

• The recovery goal for the Gray Ratsnake in Ontario is to retain the current distribution, population size and connectivity among extant sub-populations within the Frontenac Axis population of eastern Ontario and to achieve self-sustaining sub-populations in the Carolinian population by increasing the distribution and size of the population.

The Government Response Statement for the province of Ontario lists the following goal for the recovery of the Gray Ratsnake in Ontario:

• The government’s goal for the recovery of the Gray Ratsnake is to maintain a viable self-sustaining Frontenac Axis population and to halt the decline of the Carolinian population. The government supports investigating the feasibility of increasing the distribution and size of the Carolinian population.

Under SARA, population and distribution objectives for the species must be established. Consistent with the goal set out in the Government of Ontario’s Government Response Statement, Environment and Climate Change Canada’s population and distribution objectives for the Gray Ratsnake in Canada are:

• To maintain the current abundance, area of occupancy and habitat connectivity within the Gray Ratsnake, Great Lakes/St. Lawrence population; and
• To maintain and, where biologically and technically feasible, increase the current abundance, area of occupancy and habitat connectivity within the subpopulations of the Gray Ratsnake, Carolinian population.

The Great Lakes/St. Lawrence population is relatively large and currently self-sustaining, but threats to habitat (e.g., fragmentation) and road mortality have led to declines. The Great Lakes/St. Lawrence population in Canada is estimated to contain approximately 25,000 – 85,000 individuals, and the Index of Area of Occupancy is estimated at < 1,500 km² (COSEWIC 2007); however, declines in these estimates have likely occurred since surveys were last conducted. Regular monitoring using standard methods should indicate if the abundance and area of occupancy of the population is being maintained and that estimates of abundance meet or exceed previous reports.

It is unknown whether the Carolinian population will persist due to its small size and isolation, as well as the severe fragmentation of remaining suitable habitat (COSEWIC 2007). As such, consistent with the provincial goal, the objective is to maintain the population and if found to be feasible, increase its size, distribution and habitat connectivity. Maintaining and, where feasible, increasing the size, and distribution of the Carolinian population of Gray Ratsnake will require improving habitat connectivity, and it will likely be necessary to conduct active habitat restoration within subpopulations in order to maintain the population and therefore halt further declines. The protection of remaining high quality movement habitat and identifying key priority sites for restoration are required to reduce isolation, fragmentation and the potential for inbreeding depression^Footnote14; thus supporting these objectives.

5. Broad strategies and general approaches to meet objectives

The government-led and government-supported action tables from Gray Ratsnake – Carolinian and Frontenac Axis Populations – Ontario Government Response Statement (Part 3) are adopted as the broad strategies and general approaches to meet the population and distribution objectives. Environment and Climate Change Canada is not adopting the approaches identified in section 2.3 of the Recovery Strategy for the Gray Ratsnake (Pantherophis spiloides) Carolinian and Frontenac Axis populations in Ontario (Part 2).

6. Critical habitat

6.1 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 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’.

Identification of critical habitat is not a component of provincial recovery strategies under the Province of Ontario’s ESA. However, following completion of the provincial recovery strategy for this species, a provincial habitat regulation was developed for each of the Gray Ratsnake populations, and both regulations came into force July 1, 2012. A habitat regulation is a legal instrument that prescribes an area that will be protected^Footnote15 as the habitat of the species by the Province of Ontario. The habitat regulation identifies the geographic area within which the habitat for the species is prescribed and the regulation may apply, and explains how the boundaries of regulated habitat are determined (based on biophysical and other attributes). The regulation is dynamic and automatically in effect whenever the condition(s) described in the regulation are met within a specified geographic area.

Environment and Climate Change Canada adopts the description of Gray Ratsnake (Frontenac Axis population) and Gray Ratsnake (Carolinian population) habitats under sections 27.2 and 27.1, respectively, of Ontario Regulation 242/08 made under the provincial ESA as critical habitat for the Gray Ratsnake (Great Lakes/St. Lawrence and Carolinian populations). The provincial habitat regulation is dynamic and automatically in effect whenever the conditions described in the regulation are met, however, areas identified as critical habitat within this recovery strategy will remain as critical habitat until revised in an updated recovery strategy or subsequent action plan.  Additional critical habitat may be added in the future if new information supports the inclusion of areas beyond those currently identified.

The area defined under both of Ontario’s habitat regulations contains the biophysical attributes required by the Gray Ratsnake (Carolinian and Great Lakes/St. Lawrence populations) to carry out its life processes. To meet specific requirements of SARA, the biophysical attributes and geographic locations of critical habitat for each species are further detailed in the subsections below.

6.1.1. Critical habitat for Gray Ratsnake (Great Lakes/St. Lawrence population)

Ontario habitat regulation

The areas prescribed under Ontario regulation 242/08 – Gray Ratsnake (Frontenac Axis population) habitat are described as follows:

27.2 (1) For the purpose of clause (a) of the definition of “habitat” in subsection 2 (1) of the Act, the areas described in subsection (2) that are located in the following geographic areas and parts of geographic areas are prescribed as the habitat of gray ratsnake (Frontenac Axis population):

1. The geographic area of Leeds and Grenville.
2. The parts of the geographic area of Frontenac composed of the lower-tier municipalities of Central Frontenac, Frontenac Islands and South Frontenac and the single-tier municipality of Kingston.
3. The parts of the geographic area of Lanark composed of the lower-tier municipalities of Drummond-North Elmsley and Tay Valley. O. Reg. 122/12, s. 4.

(2) Subsection (1) applies to the following areas:

1. A gray ratsnake (Frontenac Axis population) hibernaculum.
2. The area within 150 metres of the area described in paragraph 1.
3. A naturally occurring gray ratsnake (Frontenac Axis population) egg laying site that is being used, or has been used at any time in the previous three years, by a gray ratsnake (Frontenac Axis population).
4. A gray ratsnake (Frontenac Axis population) egg laying site, other than a naturally occurring egg laying site, being used by a gray ratsnake (Frontenac Axis population) from the time it is used until the following November 30.
5. A naturally occurring gray ratsnake (Frontenac Axis population) shedding or basking site that is being used, or has been used at any time in the previous three years, by two or more gray ratsnakes (Frontenac Axis population).
6. A gray ratsnake (Frontenac Axis population) shedding or basking site, other than a naturally occurring shedding or basking site, that is being used by two or more gray ratsnakes (Frontenac Axis population) from the time it is used until the following November 30.
7. The area within 30 metres of an area described in paragraph 3, 4, 5 or 6.
8. Any part of a rock barren, forest, hedge row, shoreline, old field, wetland or similar area that is being used by a gray ratsnake (Frontenac Axis population) or on which a gray ratsnake (Frontenac Axis population) directly depends to carry on its life processes.
9. An area that provides suitable foraging, thermoregulation, or hibernation conditions for gray ratsnake (Frontenac Axis population) that is within 1,000 metres of an area described in paragraph 8.
10. An area that provides suitable conditions for gray ratsnake (Frontenac Axis population) to move between areas described in paragraphs 1 through 9. O. Reg. 122/12, s. 4.

(3) Subsection (1) does not apply to,

1. an area that is part of a lake or river below the historical low water mark; or
2. an area that was used to grow corn, potatoes, soya beans, wheat or any other row crop in the previous 12 months. O. Reg. 122/12, s. 4.

The habitat for the Gray Ratsnake (Frontenac Axis population) is protected under the ESA 2007 so long as the specified area has been used within the prescribed period of time, outlined above. The 150 m distance around a hibernaculum and 30 m distance around an egg laying or communal shedding or basking site is intended to protect the feature itself and the terrestrial area required to maintain the suitability of the site. The three year term represents approximately the time period in which Gray Ratsnakes (Frontenac Axis population) may use naturally occurring egg laying sites, communal shedding sites and communal basking sites. For non-naturally occurring egg laying, shedding, and basking sites, protection is limited to the active season and ends November 30 of the year of use. This allows the species to complete its life processes without disturbance yet allows for potential removal or disturbance of the feature once the active season is over (e.g., removal of materials such as old metal sheets, compost piles, etc.). The removal of such features outside of the active season will not disturb the individuals of the species and it is likely that similar features can be found the following year . The 1000 m distance represents the average distance traveled by Gray Ratsnakes (Frontenac Axis population) from their hibernacula, and is meant to protect an individual’s home range.

Biophysical attributes of critical habitat

The area of habitat defined under Ontario’s habitat regulation contains the biophysical attributes required by Gray Ratsnake (Great Lakes/St. Lawrence population) to carry out its life processes. For the purposes of defining critical habitat, these biophysical attributes are described in Table 1.

a Non-naturally occurring features are human-constructed or maintained structures with a primary purpose other than providing habitat for wildlife (e.g., barns and wells).

b Egg laying.

c The process of raising or lowering body temperature by varying exposure to environmental conditions.

Areas suitable for Gray Ratsnakes (Great Lakes/St. Lawrence population), including areas used for thermoregulation, foraging, oviposition and hibernation, are typically found in rock barren, forest, hedgerow, shoreline, old field, wetland and other similar areas that together create a mosaic of forest, forest edge and open habitat with high edge to area ratio (Weatherhead and Charland 1985; Blouin-Demers and Weatherhead 2001a; Row 2006; COSEWIC 2007).

Non-natural habitat features

As explained above, non-naturally occurring features (e.g., compost piles, old wells) have been included in the identification of critical habitat for the Gray Ratsnake (Great Lakes/St. Lawrence population) to support the species’ recovery. Recent genetic studies indicate that it is unlikely that the population could withstand much habitat loss and still remain self-sustaining (Prior et al. 1997; Howes et al. 2009), and because of the species high fidelity to hibernacula and the high importance of egg laying sites (particularly those which are communal) to the species, non-naturally occurring features which provide this type of habitat are important, especially in areas where natural habitat has been lost or is insufficient for the species needs. Additionally, as Gray Ratsnakes are at the northern extent of their range, thermoregulation is particularly important (Blouin-Demers and Weatherhead 2001b) and basking sites are often used prior to or following oviposition. Thus, non-naturally occurring features which provide thermoregulatory characteristics as identified in Table 1 should be left in place where found during the active season.

It may be possible to replace the function served by non-natural structures or features should they need to be removed or disturbed after the active season. However, this determination will need to be done on a case-by-case basis taking into consideration a number of factors including the species’ biology, potential risk to the species, the availability of natural and non-natural structures or features in the surrounding area, and options for mitigation or replacement.

Critical habitat criteria

Hibernacula are one of the most important habitat features for Gray Ratsnake (Great Lakes/St. Lawrence population) as they are critical for over winter survival. It is not currently known to what extent subterranean features of hibernacula extend from an entrance or exit point. A distance of 150 m around a hibernaculum is considered necessary to maintain the physical and biological composition, structure and function of the surrounding subterranean environment and to protect staging areas in the vicinity of the hibernacula used in the spring and fall (Blouin-Demers and Weatherhead  2002a). 

Because of their close relationship with survival and recruitment of individuals as well as some ecological traits of the Gray Ratsnake (e.g., reproductive strategy), oviposition, basking and shedding habitats are also addressed separately from other, more general habitats. The 30 m distance around an oviposition, shedding or thermoregulation site was chosen to ensure that the thermoregulatory, vegetative and lighting properties of the site are maintained (Kraus et al. 2010).

The maintenance of a healthy Gray Ratsnake population (Great Lakes/St. Lawrence population) will require connectivity of forest and forest edge habitats to enable gene flow between snakes from neighbouring hibernacula as well as permitting snakes to move between areas used for thermoregulation, foraging and oviposition. Based on the average distance that radio-tracked Gray Ratsnakes (Great Lakes/St. Lawrence population) traveled from their hibernaculum to their oviposition site (Kraus et al. 2010), a radial distance of 1,000 m is used to determine the extent of critical habitat.

Lakes and rivers, below the historical low water mark, as well as agricultural fields in row crops or in crop rotation do not contain the attributes of critical habitat and are therefore not included in the identification of critical habitat.  Use of these habitats can result in increased rates of mortality and such habitats may become ecological traps^Footnote16.

Through this recovery strategy, the areas prescribed as habitat for the Gray Ratsnake (Frontenac Axis population) under section 27.2 of Ontario Regulation 242/08 become critical habitat identified under SARA. The identification of critical habitat is based on available observations (up to March 2015) for the Gray Ratsnake (Great Lakes/St. Lawrence population) from the past 50 years. The Gray Ratsnake (Great Lakes/St. Lawrence population) is a relatively cryptic species, has a life span of about 30 years (Blouin-Demers et al. 2002) and survey effort in some locations is limited, thus it is appropriate to include observations from the past 50 years unless the habitat has been determined to no longer be suitable or the location has been designated as extirpated by the Ontario Natural Heritage Information Centre (NHIC)^Footnote17.

While the provincial habitat regulation is dynamic and automatically in effect whenever the conditions described in the regulation are met, the areas identified as critical habitat within this recovery strategy will remain as critical habitat until revised in an updated recovery strategy or subsequent action plan. Furthermore, if any new locations of the Gray Ratsnake (Frontenac Axis population) or its habitat features are confirmed within the geographic areas listed under subsection (1) of the regulation (see Figure A-1), the habitat regulation under the ESA will automatically apply to these new locations. Refer to the Habitat Protection Summary for Gray Ratsnake (Frontenac Axis Population) (OMNR 2012a) for further details on the provincial habitat regulation and its application. Should new occurrences of Gray Ratsnake (Great Lakes/St. Lawrence population) be identified that meet the criteria above, the area will not automatically become critical habitat; however, the additional critical habitat would be identified in an updated recovery strategy or a subsequent action plan.

Application of critical habitat criteria

Application of the critical habitat criteria above to the best available data identifies critical habitat for the Gray Ratsnake (Great Lakes/St. Lawrence population). The total area within which critical habitat for the Gray Ratsnake (Great Lakes/St. Lawrence population) is found is 70,614 ha (Figure B-1, See also Table B-1). The total area estimate is derived from a 1,000 m radial distance boundary around a Gray Ratsnake (Great Lakes/St. Lawrence population) occurrence, merging overlapping boundaries. Actual critical habitat within this area occurs only in those areas described in subsections 2 and 3 of the provincial habitat regulation for Gray Ratsnake (Frontenac Axis population), and therefore the actual area would likely be less than reported and would require field verification to develop a more precise estimate. The areas derived from a 150 m and 30 m radial distance around identified hibernaculum and egg laying, shedding or basking sites, respectively, are included within this estimate where known. The critical habitat identified is considered sufficient to meet the population and distribution objectives for the Gray Ratsnake (Great Lakes/St. Lawrence population); therefore a schedule of studies is not required. 

Critical habitat identified for the Gray Ratsnake (Great Lakes/St. Lawrence population) is presented using 10 X 10 km UTM^Footnote18 grid squares. Critical habitat was presented at this scale to minimize risk to the species from persecution and human disturbance. The UTM grid squares presented in Figure B-1 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. The areas of critical habitat within each grid square occur where the description of critical habitat above is met. More detailed information on the regulated habitat may be requested on a need to know basis from the Ontario Ministry of Natural Resources and Forestry. 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 at: ec.planificationduretablissement-recoveryplanning.ec@canada.ca

6.1.2. Critical habitat for Gray Ratsnake (Carolinian population)

Ontario Habitat Regulation

The areas prescribed under Ontario regulation 242/08 – Gray Ratsnake (Carolinian population) habitat are described as follows:

27.1 (1) For the purpose of clause (a) of the definition of “habitat” in subsection 2 (1) of the Act, the areas described in subsection (2) that are located in the following geographic areas and parts of geographic areas are prescribed as the habitat of gray ratsnake (Carolinian population):

1. The geographic areas of Brant, Elgin, Haldimand, Niagara and Norfolk.
2. The part of the geographic area of Middlesex composed of the upper-tier municipality of Middlesex. O. Reg. 122/12, s. 4.

(2) Subsection (1) applies to the following areas:

1. A gray ratsnake (Carolinian population) hibernaculum.
2. The area within 150 metres of the area described in paragraph 1.
3. A naturally occurring gray ratsnake (Carolinian population) egg laying site that is being used, or has been used at any time in the previous three years, by a gray ratsnake (Carolinian population).
4. A gray ratsnake (Carolinian population) egg laying site, other than a naturally occurring egg laying site, being used by a gray ratsnake (Carolinian population) from the time it is used until the following November 30.
5. A naturally occurring gray ratsnake (Carolinian population) shedding or basking site that is being used, or has been used at any time in the previous three years, by two or more gray ratsnakes (Carolinian population).
6. A gray ratsnake (Carolinian population) shedding or basking site, other than a naturally occurring shedding or basking site, that is being used by two or more gray ratsnakes (Carolinian population) from the time it is used until the following November 30.
7. The area within 30 metres of an area described in paragraph 3, 4, 5 or 6.
8. Any part of a meadow, forest, hedge row, shoreline, old field, wetland or similar area that is being used by a gray ratsnake (Carolinian population) or on which a gray ratsnake (Carolinian population) directly depends to carry on its life processes.
9. An area that provides suitable foraging, thermoregulation, or hibernation conditions for gray ratsnake (Carolinian population) that is within 2,000 metres of an area described in paragraph 8.
10. An area that provides suitable conditions for gray ratsnake (Carolinian population) to move between areas described in paragraphs 1 through 9. O. Reg. 122/12, s. 4.

(3) Subsection (1) does not apply to an area that is part of a lake or river below the historical low water mark. O. Reg. 122/12, s. 4.

The habitat for the Gray Ratsnake (Carolinian population) is protected under the ESA 2007 so long as the specified area has been used within the prescribed period of time, as outlined above. The 150 m distance around a hibernaculum and 30 m distance around an egg laying or communal shedding or basking site is intended to protect the feature itself and the terrestrial area required to maintain the suitability of the site. The three year term represents approximately the time period in which Gray Ratsnakes (Carolinian population) may use naturally occurring egg laying sites, communal shedding sites and communal basking sites. The 2,000 m distance represents the average maximum distance traveled by Gray Ratsnakes (Carolinian population) from their hibernacula, and is meant to protect an individual’s home range.

Biophysical attributes of critical habitat

The areas of habitat defined under Ontario’s habitat regulation contain the biophysical attributes required by Gray Ratsnake (Carolinian population) to carry out its life processes. For the purposes of defining critical habitat, these biophysical attributes are described in Table 2. Due to the restricted size of the Carolinian population, limited studies have been conducted on habitat use and movement. While some differences in habitat use (based primarily on available habitat) are known, much of the information presented in Table 2 is based on information available for the Great Lakes/St. Lawrence population.

Areas suitable for Gray Ratsnakes (Carolinian population), including areas used for thermoregulation, foraging, oviposition and hibernation, are typically found in meadow, forest, hedgerow, shoreline, old field, wetland and other similar areas that together create a mosaic of forest, forest edge and open habitat with high edge to area ratio (Weatherhead and Charland 1985; Blouin-Demers and Weatherhead 2001a; Row 2006; COSEWIC 2007).

Non-natural habitat features

As explained above, non-naturally occurring habitat (e.g., compost piles, old wells) has been included in the identification of critical habitat for the Gray Ratsnake (Carolinian population). Suitable habitat in the Carolinian region is severely restricted and heavily fragmented, and it is unknown whether enough habitat remains to support viable populations of Gray Ratsnakes (COSEWIC 2007). Because of the species high fidelity to hibernacula and the importance of egg laying sites to the species, non-naturally occurring features which provide this type of habitat are important to the species continued survival, especially in areas where natural habitat has been lost or is insufficient for the species needs. Additionally, as Gray Ratsnakes are at the northern extreme of their range, thermoregulation is particularly important (Blouin-Demers and Weatherhead 2001b) and basking sites are often used prior to or following oviposition. Thus, non-naturally occurring features which provide thermoregulatory characteristics as identified in Table 2 should be left in place where found during the active season.

It may be possible to replace the function served by non-natural structures or features should they need to be removed or disturbed after the active season. However, this determination will need to be done on a case-by-case basis taking into consideration a number of factors including the species’ biology, potential risk to the species, the availability of natural and non-natural structures or features in the surrounding area, and options for mitigation or replacement.

Critical habitat criteria

Hibernacula are one of the most important habitat features for Gray Ratsnake (Carolinian population) as they are critical for over winter survival. It is not currently known to what extent subterranean features of hibernacula extend from an entrance or exit point. A distance of 150 m around a hibernaculum is considered necessary to maintain the biological composition, structure and function of the surrounding subterranean environment and to protect staging areas in the vicinity of the hibernacula used in the spring and fall (Blouin-Demers and Weatherhead 2002a). 

Because of their close relationship with survival and recruitment of individuals as well as some ecological traits of the Gray Ratsnake (e.g., reproductive strategy), oviposition, basking and shedding habitats are also addressed separately from other, more general habitat. The 30 m distance around an oviposition, shedding or thermoregulation site was chosen to ensure that the thermoregulatory, vegetative and lighting properties of the site are maintained (Kraus et al. 2010).

The maintenance of a healthy Gray Ratsnake population (Carolinian population) will require connectivity of forest and forest edge habitats to enable gene flow between snakes from neighbouring hibernacula as well as permitting snakes to move between areas used for thermoregulation, foraging and oviposition.  Yagi and Tervo (2006) found that Gray Ratsnakes in the Oriskany sub-population travelled nearly two kilometres, thus a radial distance of 2,000 m is used to determine the extent of critical habitat.

Lakes and rivers, below the historical low water mark do not contain the attributes of critical habitat and are therefore not included in the identification of critical habitat.

Through this recovery strategy, the areas prescribed as habitat for the Gray Ratsnake (Carolinian population) under section 27.1 of Ontario Regulation 242/08 become critical habitat identified under SARA. The identification of critical habitat is based on available observations (up to March 2015) for the Gray Ratsnake (Carolinian population) from the past 50 years. The Gray Ratsnake (Carolinian population) is a relatively cryptic species, has a life span of about 30 years (Blouin-Demers et al. 2002) and recent survey effort in some locations is limited, thus it is appropriate to include observations from the past 50 years unless the habitat has been determined to no longer be suitable or the location has been designated as extirpated by the Ontario Natural Heritage Information Centre (NHIC).

While the provincial habitat regulation is dynamic and automatically in effect whenever the conditions described in the regulation are met, the areas identified as critical habitat within this recovery strategy will remain as critical habitat until revised in an updated recovery strategy or subsequent action plan. Furthermore, if any new locations of the Gray Ratsnake (Carolinian population) or its habitat features are confirmed within the geographic areas listed under subsection (1) of the regulation (see Figure A-2), the habitat regulation under the ESA will automatically apply to these new locations. Refer to the Habitat Protection Summary for Gray Ratsnake (Carolinian Population) (OMNR 2012b) for further details on the provincial habitat regulation and its application. Should new occurrences of Gray Ratsnake (Carolinian population) be identified that meet the criteria above the area will not automatically become critical habitat; however, the additional critical habitat would be identified in an updated recovery strategy or a subsequent action plan.

Application of critical habitat criteria

Application of the critical habitat criteria above to the best available data identifies critical habitat for the Gray Ratsnake (Carolinian population). The total area within which critical habitat for the Gray Ratsnake (Carolinian population) is found is 43,990 ha  and includes area for the four known sub-populations (Figure B-2, See also Table B-2). The total area estimate is derived from a 2,000 m radial distance boundary around a Gray Ratsnake (Carolinian population) occurrence, merging overlapping boundaries. Actual critical habitat within this area occurs only in those areas described in subsections 2 and 3 of the provincial habitat regulation for Gray Ratsnake (Carolinian population), and therefore the actual area would likely be less than reported and would require field verification to develop a more precise estimate. The areas derived from a 150 m and 30 m radial distance around identified hibernaculum and egg laying, shedding or basking sites, respectively, are included within this estimate where known. The critical habitat identified is considered sufficient to meet the population and distribution objective for Gray Ratsnake (Carolinian population); therefore a schedule of studies is not required.  

Critical habitat identified for the Gray Ratsnake (Carolinian population) is presented using 10 X 10 km UTM grid squares. Critical habitat was presented at this scale to minimize risk to the species from persecution and human disturbance. The UTM grid squares presented in Figure B-2. 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. The areas of critical habitat within each grid square occur where the description of critical habitat above is met. More detailed information on the regulated habitat may be requested on a need-to-know basis from the Ontario Ministry of Natural Resources and Forestry. 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 at: ec.planificationduretablissement-recoveryplanning.ec@canada.ca.

6.2 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. Destruction of critical habitat for Gray Ratsnake (Carolinian and Great Lakes/St. Lawrence populations) can occur at a variety of scales. It may occur from an activity taking place either within or outside of the critical habitat boundary, and it may occur at any time of year.  It may be possible to replace the function served by non-natural structures or features should they need to be removed or disturbed after the active season.  Decisions on potential removal/disturbance and mitigation measures will need to be considered on a case-by case basis.  Activities described in Table 3 include those likely to cause destruction of critical habitat for the species; however, destructive activities are not necessarily limited to those listed.

7. Measuring progress

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

• The current abundance and area of occupancy of the Great Lakes/St. Lawrence population, and the degree of habitat connectivity within the population, have been maintained.
• The Carolinian population has been maintained, and where biologically and technically feasible, the current abundance, area of occupancy and habitat connectivity within subpopulations have been increased.

8. Statement on action plans

The Parks Canada Agency completed the Multi-species Action Plan for the Thousand Islands National Park of Canada in 2015 and this document will contribute towards implementation of this recovery strategy.

One or more additional action plans will be completed and posted on the Species at Risk Public Registry for Gray Ratsnake by December 31, 2023.

9. 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.

In general, protecting this species and its habitat will benefit other species of multiple taxa, as the Gray Ratsnake is both predator and prey for a number of species (e.g., it provides an important component of a healthy ecosystem, food for some species, and a form of natural population control for others). Gray Ratsnakes also use multiple habitat types over large areas (i.e., mixed and deciduous forest, open areas such as rocky outcrops, wetlands, and small fields, and the edge habitat between forest and open habitats; see Part 2), and protection of these habitats will maintain habitat for other species as well (e.g., Cerulean Warblers, Golden-winged Warblers, Flooded Jellyskin, Pale-bellied Frost Lichen, Eastern Loggerhead Shrikes). Protection of natural features in the Carolinian region in particular will be of benefit to many species as the natural habitat in that region is already quite fragmented. The Carolinian ecosystem itself is one of the most threatened in Ontario and supports over 125 species at risk, such as Spotted Wintergreen, Red Mulberry, Cucumber Tree, Henslow’s Sparrow, Yellow-breasted Chat, Fowler’s Toad, and Queensnake.

The potential for this recovery strategy to inadvertently lead to adverse effects on other species was considered. None of the management activities proposed includes activities that would negatively affect other species. The SEA concluded that this strategy will clearly benefit the environment and will not entail significant adverse effects.

References

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Baxter-Gilbert J.H., J.L. Riley, D. Lesbarrères, J.D. Litzgus. 2015. Mitigating Reptile Road Mortality: Fence Failures Compromise Ecopassage Effectiveness. PLoS ONE 10(3): e0120537. doi:10.1371/journal.pone.0120537

Blouin-Demers, G., and P.J. Weatherhead. 2001a. Habitat use by black rat snakes (Elaphe obsoleta obsoleta) in fragmented forests. Ecology 82:2882-2896.

Blouin-Demers, G., and P.J. Weatherhead. 2001b. Thermal ecology of black rat snakes (Elaphe obsoleta) in a thermally challenging environment. Ecology 82:3025-3043.

Blouin-Demers, G., and P.J. Weatherhead. 2002a. Implications of movement patterns for gene flow in black rat snakes (Elaphe obsoleta). Canadian Journal of Zoology 80:1162-1172.

Blouin-Demers, G. and P.J. Weatherhead. 2002b. Habitat-specific behavioural thermoregulation by black rat snakes (Elaphe obsoleta obsoleta). Oikos 97: 59-68.

Blouin-Demers, G., P.J. Weatherhead, and J.R. Row. 2004. Phenotypic consequences of nest-site selection in black rat snakes (Elaphe obsoleta). Canadian Journal of Zoology 82:449–456.

Clark, R.W., M.N. Marchand, B.J. Clifford, R. Stechert, S. Stephens. 2011. Decline of an isolated timber rattlesnake (Crotalus horridus) population: interactions between climate change, disease, and loss of genetic diversity. Biological Conservation 144, 886-891.

COSEWIC. 2007. COSEWIC assessment and update status report on the Gray Ratsnake Elaphe spiloides (Great Lakes/St. Lawrence population and Carolinian population) in Canada. Committee on the Status of Endangered Wildlife in Canada. Ottawa. vii + 33 pp.

COSEWIC. 2009. Guidelines for use of the Index of Area of Occupancy (IAO) in COSEWIC Assessments. Website: [accessed June 2015]

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Howes, B.J., J.W. Brown, H.L. Gibbs, T.B. Herman, S.W. Mockford, K.A. Prior and P.J. Weatherhead. 2009. Directional gene flow patterns in disjunct populations of the black ratsnake (Pantherophis obsoletus) and the Blanding’s turtle (Emydoidea blandingii). Conservation Genetics 10:407-417.

Kelly, A. and M. Seidel. 2015. Conservation Biology Blueprint for Seven Threatened Species Found in the Region between Frontenac Provincial Park and Charleston Lake Provincial Park. Report for course ENSC 430, Queen’s University. 84 pp. QSpace - Queen's Reseach and Learning Resporitory

Kraus, T., B. Hutchinson, S. Thompson and K. Prior. 2010. Recovery Strategy for the Gray Ratsnake (Pantherophis spiloides) – Carolinian and Frontenac Axis populations in Ontario. Ontario Recovery Strategy Series. Prepared for the Ontario Ministry of Natural Resources, Peterborough, Ontario. vi + 23 pp.

Langwig, K. E., J. Voyles, M. Q. Wilber, W. F. Frick1, K. A. Murray, B. M. Bolker, J. P. Collins, T. L. Cheng, M. C. Fisher, J. R. Hoyt, D. L. Lindner, H. I. McCallum, R. Puschendorf, E. B. Rosenblum, M. Toothman, C. K. R. Willis, C. J. Briggs and A. M. Kilpatrick. 2015. Context-dependent conservation responses to emerging wildlife diseases. Front. Ecol. Environ. 13(4): 195–202, doi:10.1890/140241

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Appendix A: Regulated habitat for the Gray Ratsnake in Canada

Appendix B: Critical habitat for the Gray Ratsnake in Canada

1. Based on the standard UTM Military Grid Reference System, where the first 2 digits and letter refer to 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 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).

2. The listed coordinates are a cartographic representation of where critical habitat can be found, presented as the southwest corner of the 10 x 10 km Standardized UTM grid square containing all or a portion of the critical habitat unit. The coordinates may not fall within critical habitat and are provided as a general location only.

3. 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.

1. Based on the standard UTM Military Grid Reference System, where the first 2 digits and letter refer to 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 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).

2. The listed coordinates are a cartographic representation of where critical habitat can be found, presented as the southwest corner of the 10 x 10 km Standardized UTM grid square containing all or a portion of the critical habitat unit. The coordinates may not fall within critical habitat and are provided as a general location only.

3. 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.

Appendix C: Subnational conservation ranks of Gray Ratsnake (Pantherophis spiloides) in Canada and the United States

Rank definitions (NatureServe 2014)

N1/S1: Critically imperilled (National/State) - At very high risk of extirpation in the jurisdiction due to very restricted range, very few populations or occurrences, very steep declines, severe threats, or other factors.

N2/S2: Imperilled (National/State) - At high risk of extirpation in the jurisdiction due to restricted range, few populations or occurrences, steep declines, severe threats, or other factors.

N3/S3: Vulnerable (National/State) -  At moderate risk of extirpation in the jurisdiction due to a fairly restricted range, relatively few populations or occurrences, recent and widespread declines, threats or other factors.

S4: Apparently secure (State) - At a fairly low risk of extirpation in the jurisdiction due to an extensive range and/or many populations or occurrences but with possible cause for some concern as a result of local recent declines, threats or other factors.

G5/S5/N5: Secure (Global/State/National) - At very low risk of extinction or elimination due to a very extensive range, abundant populations or occurrences, and little to no concern from declines or threats.

SU: Unrankable (State) - An occurrence rank cannot be assigned due to lack of sufficient information on the occurrence.

SH: Historical (State) - Recent field information verifying the continued occurrence is lacking.

SX: Extirpated (State) - Adequate surveys by one or more experienced observers at times and under conditions appropriate for the species at the occurrence location, or other persuasive evidence, indicate that the species no longer exists there or that the habitat or environment of the occurrence has been destroyed to such an extent that it can no longer support the species.

NNR/SNR: Unranked - National or subnational conservation status not yet assessed.

?: Used to indicate uncertainty in any of the above ranks, usually because data is lacking.