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C. Survey Protocol for the Shasta Salamander (Hydromantes shastae)
Deanna H. Olson - USDA Forest Service, Pacific Northwest Research Station, 3200 SW Jefferson Way, Corvallis, OR 97330.
Introduction
This survey protocol is used for determining the presence or absence of individuals and populations of the Shasta salamander (Hydromantes shastae; HYSH). Much of the information in this protocol is based on information and recommendations provided by Peter Lewendal (Shasta Land Management, Redding, CA; Lewendal 1995).
Potential sites are to be inventoried using a time-constrained search technique, during appropriate environmental conditions. As a general guide, appropriate habitats should be searched for 8 person-hours per 10 acres (or smaller) during each site visit. To designate absence, four site visits are required. These should be spaced by at least 21 days.
Read the entire document before initiating any survey.
1. Prerequisites for Performing Surveys.
This protocol is only to be employed by qualified biologists trained in terrestrial salamander species identification, with a full understanding of the methodology.
Prior to field work, review the literature for historical information and all available resources to determine the current known range and habitat for this species. The management recommendations for Survey and Manage amphibian species provides a comprehensive and up-to-date information for these salamanders (Olson et al. 1996, in prep.).
2. State Regulations.
The State of California has strict requirements for both the handling and collecting of these animals. Capture and handling is necessary to identify these salamanders, thus the following regulations are to be followed.
HYSH:
In California, this is a State Threatened species and it is prohibited to handle these organisms without a Memorandum of Understanding in place with California Department of Fish & Game. Taking, including collection of Voucher specimens (live or preserved), is generally prohibited and requires an additional letter of permission. The State needs to be notified if any incidental mortality occurs, and the specimen needs to be preserved and routed as per their direction.
Survey Procedures
1. Spatial and Temporal Aspects.
a. Site location.
This species appears to be largely restricted to limestone rock outcroppings in Shasta County, California. It is known from three of four major limestone belts in the area (Kennet Formation, McCloud Limestone, and Hosselkus Limestone; Lewendal 1995). Individuals have been found under surface objects in areas surrounding rock outcrops, to distances of about 90 m.
This species is apparently unique to a small area near Lake Shasta, California, however surveys have not been conducted in potential habitat in other areas of northern California. It is recommended that sites with appropriate habitat in northern California be surveyed if they occur below 3000 feet in elevation. The site should include appropriate habitat in the form of surface rock. Occupied sites generally are limestone outcrops, however, a population has been found in a volcanic rock outcrop. If the proposed project area or an area within 180 m of the perimeter of the project area (Fig. 1) has Shasta salamander habitat, then the survey protocol is triggered. Within outcrops, Shasta salamanders may occur under rocks, in fissures or caves, and on vertical cliffs. Surrounding the outcrops, individuals may be found under surface debris during appropriate environmental conditions. Habitats within 100 m of outcrops should be included in initial surveys. These salamanders have been found in several vegetation types, forested and non-forested. Few populations of this animal are known, thus decisions to survey should be made conservatively.
b. Survey timing.
Seasons -The optimal sampling period is during the wet, humid early spring, although animals have been found in the late fall and winter. If environmental conditions permit, surveys could be possible mid-November through mid-April. If animals are not being found in the first couple of visits, ONE SURVEY IS TO BE SCHEDULED AND CONDUCTED IN THE LATTER PART OF THE SPRING SURVEY SEASON, to attempt to match optimal activity conditions.
Number of Site-Visits - Each site should be visited a total of 4 times over the course of the fall-to-spring rainy season (see environmental conditions, below), unless presence is established. Sampling periods should be separated by at least 21 days to allow for site conditions to develop in response to weather regimes and to provide a sufficient time interval to allow seasonal salamander activity to be triggered. With this sampling interval, it is possible to complete a survey effort within the preferred sampling season, winter-to-spring. However, attention should be paid to environmental conditions that constrain surveys, itemized below.
These animals have been found to be nocturnally active during wet conditions, but also are found during daytime searches. Both day and night surveys can be conducted, however, for safety reasons, daytime surveys might be opted.
2. Environmental Conditions.
The activity patterns of HYSH is dependent on local environmental factors such as humidity and temperature. These factors should be taken into careful consideration when determining when to sample for these animals.
Although precise temperature and humidity guidelines have not been previously established for surveys of this salamander, they appear to be particularly active on the surface during warm tropical weather systems (P. Lewendal, pers. comm.). Until further information is available, the following temperature- moisture conditions are needed for surveys (chest height measures).
Air relative humidity: 90% or greater.
Air temperature: 4-5oC or greater during sampling.
3. Reference Sites.
Care should be taken to not overly disturb Shasta salamanders at known sites because of their extreme rarity. Routine use of Reference Sites prior to surveys of new areas is not recommended at this time.
4. Detection.
Presence within the site is established by the capture of one or more salamanders at a site. If presence has been established, no further site visits as described by this protocol are then necessary and the entire area of suitable habitat is designated the known site. If it is decided that a finer-scale delineation of the known site is necessary, additional surveys will be needed. This is discussed at the end of this protocol.
Absence can only be determined if each site has been sampled 4 times, under appropriate microclimatic conditions, and no individuals are found.
5. Voucher Specimens.
Preserved voucher specimens are not required for this species, due to its status of concern and the required training of field personnel in species identification should reduce identification errors. Photographic vouchers are suggested. This animal is not easily mis-identified, once its key characters have been assessed. If there is doubt as to the identification of a captured salamander, local species-experts can be sought to verify the identity of the animal.
Survey Method
1. Prior to sampling.
Review Survey Area
A contour map covering the specific proposed project area (e.g., forest management activity, recreational development) is needed when conducting a survey. From maps and field verification of site conditions, Shasta salamander habitats should be delineated with the project area boundary and the perimeter area. These comprise the survey area.
Thus, the survey area is defined by the habitat proposed to be affected by the management activity. The construction of a trail across a slope may require a much more restricted survey than an extensive regeneration harvest. However, if there is little HYSH habitat in the proposed harvest site, survey effort may be reduced in that scenario as well.
Survey time can be estimated once the extent of the HYSH habitat is known for the proposed project area. Timing of a survey is scaled to the size of the habitat area using the guideline of 8 person-hours per 10 acres of habitat per site-visit. For example, a two-person field crew may complete the searching of a 5 acre limestone outcrop area in two hours or a 50 acre habitat in twenty hours.
Data form entries (see Appendix 1).
a. Site location.
b. Time and date.
c. Observer name/s.
d. Weather. (record and measure at plot center prior to sampling)
e. Ambient temperature and moisture.
Measurements of air and substrate temperature and humidity are needed to validate survey conditions. Describe locations of each of three sets of measurements.
Measures:
Important! If temperature or relative humidity measures are not above the limits described in the section on environmental conditions, sampling at the site should not be continued on this day. Return at another time, when climate is appropriate.
2. Time-constrained search.
Before conducting the survey, plan the search route to give an extensive reconnaissance-level approach to the entire area, including rock outcrops and surrounding habitats. Obvious caves, highly fissured areas, rubble or cliffs should be marked and their survey approach incorporated into the search route and overall timing. Likely microhabitats can be more intensively searched, but other areas should not be ignored. "Moving rules" will help to maintain extensive surveys. For example, not spending more than 10 minutes searching a particular microsite, or designating the general area to be covered each hour of the survey, might be adequate moving rules.
Search by hand, turning cover objects, and looking into cracks and crevices as you systematically move around the area. A flashlight can facilitate surveys of dark fissures or caves. Please note: potato rakes may be used but only with extreme caution during searches. When moving to a new site or handling a capture (recording information), the timer stops. Time of search applies only to time spent actively searching for animals.
Keep track of time each observer spends searching.
If animals are captured, record the following information:
a. Species - four-letter code (see code sheet) determined by identification keys provided during field training. Record all amphibian species captured.
b. Stage - juvenile/subadult or adult.
c. Capture location - describe in words, mark and map site. Individual locations might be needed if finer-scale delineation of populations is required.
All captures are to be released as close to original capture location as possible. While searching, attempt to return rocks and other large cover objects back to original positions.
When a HYSH is found, search efforts may stop, "presence" is designated, the entire habitat is designated occupied (see below), and the habitat becomes a known site and is entered into the known site database.
Delineation of Occupied Sites.
All suitable rock habitat, as determined by a qualified biologist, that is contiguous with an occupied site will be considered occupied. The full extent of the occupied suitable habitat should be delineated. If suitable habitat is separated by no more than 75 meters, then it should also be considered occupied. If there is doubt as to the occupancy status of suitable contiguous habitat, survey the site using this same survey protocol. Unoccupied habitats may be identified by additional surveys to further delineate sites. The potential ecological value of contiguous but unoccupied habitat (in terms of desired future conditions, population dynamics, and connectivity) should be considered.
Areas surrounding occupied rock outcrops may also be inhabited by Shasta salamanders and should be surveyed to delineate an occupied site. Specifically, areas within 150-200 m of occupied outcrops should be surveyed, using the same method of 8 person-hours per 10 acres of area and up to 4 site-visits. If animals are found in this perimeter area, then sampling should be conducted an additional 150-200 m from the last siting(s), thus expanding the delineated site outward as necessary.
