Northern Black Racer Coluber Constrictor Constrictor
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Appendix A: Reptiles Northern Black Racer Coluber constrictor constrictor Federal Listing N/A State Listing T Global Rank G5 State Rank S2 High Regional Status Photo by Brendan Clifford Justification (Reason for Concern in NH) Based on historic reports of large populations of black racers, substantial population declines have likely occurred in New Hampshire. Racers reach the northern extent of their geographic range in central New Hampshire and southern Maine, and are listed as Endangered in Maine and Threatened in Vermont. Early successional and shrub‐dominated habitats are rapidly declining throughout the northeastern United States, largely as a result of commercial and residential development and forest maturation (Kjoss and Litvaitis 2000). In New Hampshire, remaining patches of early‐successional habitat are small and patchily distributed (Kjoss and Litvaitis 2000). Severe habitat loss, alteration, and fragmentation throughout the species’ distribution is exacerbated by the species extensive habitat requirements (Kjoss and Litvaitis 2000). Distribution A total of 11 subspecies of black racers are recognized, all of which range north of Mexico (Ernst and Ernst 2003). The Northern black racer occurs from southern Maine and central New York, southwest to eastern Tennessee, northwestern Georgia, and northeastern Alabama (Ernst and Ernst 2003). In New Hampshire, this species is restricted to areas south of the White Mountains, with the greatest number of verified records in the southeast. Within this region, black racers occur discontinuously, suggesting that populations may be confined to small pockets of optimal habitat (Klemens 1993). The species distribution map associated with this profile is based on data synthesized at the time of its creation. Distribution maps are continually being updated as new reports are received. Habitat The Northern black racer (Coluber constrictor constrictor) is a long, slender snake associated with a wide variety of early successional habitats, including brushy areas; utility right‐of‐ways; grasslands; old fields; sand pits; rocky ridges and ledges; and the edges of agricultural fields (Hunter et al. 1999, Kjoss and Litvaitis 2000, Ernst and Ernst 2003, NHFG Data). As racers move between habitat patches they may use forested habitats, particularly those that have been altered from timber harvests (NHFG Data). In New Hampshire racers appear to have much larger home ranges than those reported from more southern populations. The home ranges of 25 tracked racers in NH averaged 112 ha for males and 70 ha for females but exceeded 200 ha for some individuals (NHFG Data). Similar home range sizes have been reported from a single population in Maine (Mays and Persons 2011). Mammal burrows and rock crevices may be used as nest sites, retreats, and hibernacula (Ernst and Ernst 2003, NHFG Data). High hibernacula site fidelity is common as individuals may return to the exact crevice or a location close by (NHFG Data). These sites are normally used communally, either in New Hampshire Wildlife Action Plan Appendix A Reptile‐17 Appendix A: Reptiles intra‐ or interspecific assemblages, during the months of October through April (Ernst and Ernst 2003, NHFG Data). Juvenile prey consists primarily of insects whereas adult prey consists of frogs, toads, birds and their eggs, small mammals, and snakes, with mammals being the dominant food item (Ernst and Ernst 2003). Nesting, which also may be communal, typically occurs from the end May through June in loose soil, litter, or hollow logs (Ernst and Ernst 2003, Mays and Persons 2011). Hatchlings emerge in August or September (Hunter et al. 1999, NHFG Data). NH Wildlife Action Plan Habitats ● Shrublands ● Grasslands ● Appalachian Oak Pine Forest ● Developed Habitats ● Hemlock Hardwood Pine Forest ● Rocky Ridge ● Cliff ● and Talus Distribution Map Current Species and Habitat Condition in New Hampshire Populations are likely smaller and more fragmented than historic levels based on historic reports and the current level of human development that have reduced habitat. In a historic report (1940‐1950, specific date unknown) Donald Carle, professor of science at Keene Teachers College, noted that 112 black racers were found at one location in Keene. In a multi‐year study on the movement and habitat‐ use of black racers in New Hampshire, 3 populations with greater than 25 individuals were documented with mark‐recapture techniques and an additional 5 populations had greater than 10 individuals marked (NHFG Data). Still, most statewide records (Element Occurrences) consist of single individuals and no site or population information exists (NHB Data). Population Management Status During 2009‐2015, NHFG surveyed 9 racer populations with mark‐recapture techniques and radio‐ telemetry to document the population sizes and delineate the approximate site boundaries. Site‐ specific threats have been identified for several populations which will be incorporated into local management plans. New Hampshire Wildlife Action Plan Appendix A Reptile‐18 Appendix A: Reptiles Regulatory Protection (for explanations, see Appendix I) ● NHFG Rule FIS 803.02. Importation. ● NHFG Rule FIS 804.02. Possession. ● NHFG Rule FIS 811.01 Sale of Reptiles. ● Endangered Species Conservation Act (RSA 212‐A) ● NHFG FIS 1400 Nongame special rules ● Fill and Dredge in Wetlands ‐ NHDES Quality of Habitat Data on the presence and condition of most shrubland habitats in New Hampshire is insufficient. The largest shrubland habitats in the state are likely associated with utility right‐of‐ways that are maintained as early‐successional habitat. Large powerline corridors that have limited road crossings can provide suitable habitat for some populations (NHFG Data). Active sand and gravel pits may provide suitable habitat in some areas but are also likely to put individual snakes at risk to direct mortality (NHFG data). Abandoned pits that are left to re‐vegetate naturally provide ideal habitat conditions that may exists for decades although these areas are often targeted for reclamation by landowners thereby reducing the habitat quality. The remaining shrubland habitats in the state are mostly small, disjunct patches associated with old fields, regenerating clearcuts, the edges of agricultural fields or un‐kept sections of backyards. While racers will readily use these habitats they are often too small to hold individuals for extended periods. Habitat patches associated with backyards or the edges of industrial lots are likely to increase encounters with roads or people. The habitat quality varied at nine racer sites that were surveyed by NHFG. Five sites had powerline right‐of‐ways where several individual racers spent the majority of the active season, although snakes were not confined to the right‐of‐way and moved back and forth to nearby fields (NHFG Data). Flood control structures (e.g., rip rap dikes) and the associated landscape were heavily used at two sites and are likely to provide stable and suitable habitat patches for those populations. Two sites were comprised primarily of smaller habitat patches associated with agricultural fields and backyards. However, despite some sites having larger and higher quality habitat patches, racers were documented using the edges of yards at eight of nine sites, although the frequency varied between sites. Habitat Protection Status The amount of conserved land at the NHFG survey sites (n = 9) ranged from less than 5% to greater than 90% of the site. At four sites less than 10% of the land is in conservation with none of the known hibernacula protected. More than 50% of the land is protected at five sites with the hibernacula on conserved land at four of these sites. Although the majority of Element Occurrence records in the Rare Species Database are on private lands, these records may be representative of long distance movements and the site boundaries and protection status cannot be determined without further investigation. Habitat Management Status There has been little habitat management conducted in New Hampshire specifically for black racers, but management for early‐successional habitat that has been targeted toward other species (e.g., New England cottontail, American woodcock) has likely benefitted racers at some sites. Land‐use activities such as timber harvesting and rotational mowing of utility right‐of‐ways are conducted statewide and are likely to enhance or maintain racer habitat where they occur. New Hampshire Wildlife Action Plan Appendix A Reptile‐19 Appendix A: Reptiles Threats to this Species or Habitat in NH Threat rankings were calculated by groups of taxonomic or habitat experts using a multistep process (details in Chapter 4). Each threat was ranked for these factors: Spatial Extent, Severity, Immediacy, Certainty, and Reversibility (ability to address the threat). These combined scores produced one overall threat score. Only threats that received a “medium” or “high” score have accompanying text in this profile. Threats that have a low spatial extent, are unlikely to occur in the next ten years, or there is uncertainty in the data will be ranked lower due to these factors. Habitat conversion due to development of upland habitat (Threat Rank: High) Racers have extensive home ranges and travel between several habitat patches during their active season. Patches that are lost to development force racers to shift their home ranges which may increase the risk of road crossings or human encounters. While the loss of small patches may not be immediately