Endangered and Threatened Animal Species Inventory
Laurel Creek Project, Transylvania County, NC
by
Chistopher R. Wilson, Consulting Zoologist
Appalachian Ecological Consultants
425 Roxanna St., Boone, NC. 28607. (828) 264-0928
critterfro@interpath.com
Background
The Laurel Creek Project Area is a proposed limited housing development and conservation easement donation in Transylvania Co., NC. The area is located approximately 4.5 air miles southeast of Brevard in the USGS Brevard Quadrangle and is bordered to the south by Duke State Forest. The northern two-thirds of the project area consists of a major ridge running in a general north-south direction with coves draining the western slopes into Williamson Creek and the Eastern slopes into Laurel Creek. The southern third of the project area is series of coves with a general north-east aspect draining into the East Fork of Laurel Creek. Elevations range between 2500 ft and 3100 ft.
Study Area / 1:100k USGS Hendersonville Topo
Major forest types of the Laurel Creek Project include Montane Oak-Hickory, Acidic Cove, and "Semi"Rich Cove (see Laurel Creek Baseline Documentation by Kevin Caldwell for detailed descriptions). In general, ridges are dominated by Oak/ Hickory with Kalmia understory and the coves are mostly acidic with Kalmia and/or Rhododendron understories (see Map 1).
Other than a small Appalachian Seep Community, there are no bogs, ponds, or wetlands in the project area.
Methodology
The inventory targeted Federal and State listed vertebrate and butterfly species and their habitats as indicated in the Natural Heritage Program List of the Rare Animal Species of North Carolina (LeGrand and Hall, 1999) and other available literature.
On 26 March, 6 & 25 May, and 2 July 2000, I surveyed the Laurel Creek area for rare species and assessed habitat conditions. Birds were surveyed by sight, song, and call during early morning hours. Searches for tracks, scat, and sign were used to determine presence of mammals. Herpetiles were searched by turning cover objects and raking trough leaf-litter and debris. Butterflies were identified by sight. The survey took place during a time of year that offers high detectability of targeted species. Terrestrial and aquatic habitats were inspected to determine suitability for various species.
NCNHP Rare Animal occurrence records for Transylvania CO. (Table 1) were reviewed to determine likelihood of occurrence in the study area based on the presence of potential habitats.
Results
4 Endangered, Threatened, Rare, or Watch List species were detected in the Laurel Creek Project Area and are discussed below.
Potential habitat was observed for 9 Endangered, Threatened, Rare, or Watch List species and are listed in Table 2. In particular, potential habitat was observed for 1 State Endangered Species which is discussed below.
62 wildlife species were detected in the project area and are listed in Table 3.
Endangered, Threatened, Rare, or Watch List species detected in the Laurel Creek Project Area
(see Table 3 for Status Codes)
Appalachian Yellow-bellied Sapsucker, ( SR/FSC): I observed the characteristic horizontal rows of boring holes made by this species. While this observation indicates that Sapsuckers forage in the project area (most likely in winter) it is doubtful that they breed here. Because NCNHP only tracks breeding occurrences of this species, there are no NCNHP records for Sapsuckers in Transylvania CO. (see Map2, YBSapSuck)
Diana Fritillary Butterfly, (SR/FSC): Several males were seen cruising the forest road-sides within the project area. The Diana Fritillary inhabits mountainous areas with moist and well shaded forests, rich soils, and populations of Viola spp. which are used as caterpillar host plants. In the adult phase, the Diana uses small forest openings in search of mates and nectering plants but never strays far from the forest itself. Forest road-sides are frequently used for nectering and are where this species is most conspicuous. This species has decreased in range due to logging (National Audubon Society Field Guide to North American Butterflies, 1995). (see Map2, Diana)
Southern Appalachian Salamander, (W3/-): one individual was found under a log adjacent to the main dirt road at the northern entrance. Although this species is locally common in appropriate habitat, it is endemic to the Southern Appalachians and has a very small range making it vulnerable to extinction. (see Map2, SAppSal)
Black Bear; (W2,W5/-) several scats were observed along the edge of the main road in the center of the project area. With the abundance of roadless forest to the south (Duke Forest), Black Bears may be expected to traverse the project area in the future in search of food, mates, or territories using ridge-tops and ravines as travel corridors. (See Map2, Bear)
Potential Habitat for Endangered Species
Green Salamander (E/FSC): Suitable rock outcrops were located and searched in the southern third of the project area (see Map2, PGreen1 & PGreen2). No Green Salamanders were found in the study area but two new records were discovered on adjacent properties. The first site was discovered by Jeff Corser in early May on Cascade Lake Rd near Laurel Creek, 2500 ft to the East of the project boundary (see Map2, Green1). A second site was discovered by Corser and myself on 25 May, 1300 ft to the south of the project boundary (see Map2, Green2). Both new sites contained one adult male Green Salamander.
Green Salamander discovered adjacent to project area. Tail tip was collected for a phylogenetic study.
Mae Lee Hafer, currently a USFS wildlife biologist at the Pisgah Ranger Station, developed a set of criteria to rate 400m x 400m cells of USGS topo quads as having high probabilities of containing Green Salamanders. In 1992 she applied this method to the Brevard Quad (Survey of the Green Salamander, Aneides aeneus, in Southern Transylvania County, North Carolina (Brevard 7.5' Quadrangle), 1992, Mae lee A. Hafer, NCWRC). Her study indicates 7 high probability cells overlapping portions the project area and several more in the vicinity (see Map3).
Due to the presence of suitable rock outcrops, nearby populations, and the results of Mae Lee Hafer's work, it is highly probable that Green Salamanders occur in the project area, most likely in the coves within southern third of the property. These observations are notable because this species is State Endangered and may be proposed for Federal listing in the near future.
Aquatic Conditions
Williamson Creek and Laurel Creek were the only streams large enough to have potential for fish populations. Williamson Creek contained the least sedimentation (degree of substrate embeddedness in pools) and the highest potential for Brook Trout. However, the stream also maintained a very low flow rate and much of the stream substrate is bedrock. Laurel Creek has a higher flow rate yet the substrate is significantly embedded with fine sediments. This creek is likely receiving sediment inputs from unpaved roads upstream to the southwest of the property. Although I did not measure stream temperature, both streams appeared too warm for Brook Trout. Also, the streams may contain fish barriers (such as waterfalls) downstream from the project area preventing colonization.
I reviewed the habitat requirements and ranges of each fish species listed in the NCNHP element occurrence records for Transylvania CO. Based on the available literature and my field observations, no rare fish species are likely to occur in the project area. In addition, it is my opinion that neither stream contains Brook Trout, however, electro-shock fish surveys would increase certainty.
Additional Surveys
A fish survey using electro-shock techniques is planned for the summer of 2000 and the results will be appended to this report.
Recommendations for Conservation
The Laurel Creek Project contains biologically sensitive areas and potential habitat for State Endangered species. Due to the richness of Laurel Creek Cove, Williamson Creek Cove, and the entire stretch south of Laurel Creek, I recommend donating these areas as a Conservation Easement. I have included a map delineating a suggested conservation easement based on the report by Kevin Caldwell (see Map 4). This easement covers approximately 223 contiguous acres and will protect the most critical areas for all of the observed and potential rare species within the project area including habitat for the state endangered Green Salamander. The easement will also protect the majority of rare plant species and stream reaches within the project area (see Caldwell) and will extend the effective size of the Duke State Forest.
Within the areas to be developed, I recommend the following:
- Avoid disturbance to coves which often contain the most biotic diversity and the steepest slopes.
- Minimize the size of all canopy gaps. Large canopy gaps will change the floral and faunal species composition from an interior forest community to an edge community. In particular, bird populations are susceptible to brood parasites and predators associated with edges. Large canopy gaps also reduce substrate moisture reducing habitat for amphibians and small mammals.
- Leave the largest buffer strips possible along streams and seeps. Riparian buffers greatly reduce stream sedimentation, maintain cool stream temperatures and shading, supply woody debris for structure and nutrients, and are often used as corridors by many species of wildlife. A riparian buffer should consist of a core riparian habitat plus a core-buffer to protect from edge effects. Keep in mind edge-effects on salamanders are known to extend up to 35 meters into the core, particularly in south facing edges (deMaynadier et. Al, 1998. Effects of silvicultural edges on the distribution and abundance of amphibians in Maine. Conservation Biology 12:340-352). Although it may not be practical for all streams within the project area, I suggest a minimum buffer of 200 ft on streams and seeps, particularly those with steep adjacent slopes.
- Take all precautions to reduce sedimentation in streams during development through use of silt fencing, holding ponds, and restricting grading to dryer seasons of the year. Minimize the area of exposed surfaces and sow native grass seed on areas that will be exposed for extended periods (including un-used roads and paths). Pave all roads that will receive frequent use; paved roads produce less sediment than dirt or gravel.
- Do not remove downed woody debris and standing dead trees unnecessarily, particularly large diameter trees or those with exfoliating bark. A lack of woody debris is a limiting factor for many forest species.
- Avoid unnecessary moving or compacting of soil. Soils take thousands of years to develop. Disturbing the soil alters floral and faunal communities for extended periods of time. Fossorial animals such as small mammals and salamanders are particularly affected.
- Maintain forest cover within the ridge saddles as wildlife corridors. The main north-south ridge on the northern half of the property is frequently traversed by wildlife through the saddles as demonstrated by the abundance of game trails and tracks in these areas. Because development activities are to be concentrated on the ridge, there is a potential to fragment the two watersheds to the east and west. Maintaining forest cover and downed woody debris within the saddles and connecting ravines may ensure gene exchange across the ridge for less mobile organisms such as salamanders.
- Create small fish free ponds. A limiting factor for many lentic breeding amphibians is a lack of fish free ponds. Creating such ponds is relatively cheep and easy and will significantly increase the biodiversity on the property. A simple scoop by a bulldozer can create a breeding pond for a number of frogs and salamanders. It is important that such ponds remain free of predatory fish. Future residents may appreciate listing to the calls of breeding frogs. I suggest placing the ponds in a variety of habitats such as in heavily shaded coves near streams and on the oak/ hickory ridge-tops. Mosquitoes will be controlled once predatory insects and larval salamanders become established.
Proposed Trout Pond
The owner has expressed interest in developing trout ponds for recreational purposes by damning small portions of stream (<.25 acre) within the project area. Besides the obvious physical modifications to the stream, there are ecological effects associated with this activity. Nutrient loading down stream would occur due to the input of trout food and waste products. A top-draw dam would increase water temperatures downstream while a bottom-draw may reduce the amount of dissolved oxygen. These effects would alter the faunal and floral communities down-stream. However, these effects may dissipate rapidly downstream.
An important consideration for the success of a trout pond is sediment loading and water temperatures. Sedimentation from the proposed development, particularly roads, can fill ponds very quickly requiring frequent dredging. Because of sedimentation concerns, it may be a good idea to wait until the roads are paved and development activities are completed before creating the ponds. Also, trout require cold water temperatures around 15 - 16 degrees Celsius. In order to maintain optimal water temperatures, the pond should be at least 12 ft deep and heavily shaded. Finally, such a project may require federal or state permits due to the modification of a stream.
