Texas Nature Trackers
Texas Parks and Wildlife Department
4200 Smith School Road
Austin, TX 78744
(800) 792-1112 ext. 8062
Texas Amphibian Watch: Data Collection Guide
- Air temperature
- The best option is to have an outdoor thermometer. You can also call time/temperature phone numbers or obtain temperatures from local radio or TV; however, temperatures in rural settings often differ significantly from temperatures in nearby urban settings.
- Record the actual wind speed or use the Beaufort scale described below. Indicate the direction from which the wind is coming. (for example: B2 SW)
- B0 (less than 1 mph) – calm/still: smoke will rise vertically.
- B1 (1-3 mph) – light air: rising smoke drifts; weather vane is inactive.
- B2 (4-7 mph) – light breeze: leaves rustle; can feel wind on your face; weather vane is inactive.
- B3 (8-12 mph) – gentle breeze: leaves and twigs move around; light weight flags extend.
- B4 (13-18 mph) – moderate breeze: moves thin branches, raises dust and paper.
- B5 (19-24 mph) – fresh breeze: medium tree branches move.
- In most localities, surveys should not be conducted when wind speeds exceed 12 mph.
- Use the following National Weather Bureau guide:
- 0 – Few clouds
- 1 – Partly cloudy or variable sky
- 2 – Cloudy or overcast
- 4 – Fog or smoke
- 5 – Drizzle
- 8 – Showers
- Check a calendar to record the closest moon phase: (New moon, First quarter, Full moon, Third quarter)
- Water Level
- Describe as average, below average, above average, much below average, or much above average.
- Barometric Pressure and Relative Humidity
- These two variables may be very important in amphibian calling activity. If your site is located near a National Weather Service station, then you can obtain current data from the Internet. Some local radio and television. news programs will also provide these numbers, although they can change quickly over the course of an evening.
- Background Noise
- Low – does not impair ability to hear calls
- Medium – some noise; may obscure some calls
- High – definitely affects effectiveness of call count
- Amphibian Call Index:
- This index is used to give a very rough relative abundance for each amphibian species calling at a site.
- Index Value 0: No individuals calling.
- Index Value 1: Individuals can be counted. There is space between calls.
- Index Value 2: Calls of individuals can be distinguished, but there is some overlapping of calls.
- Index Value 3: Full chorus. Calls are constant, continuous, and overlapping.
Texas Wetland Types:
Texas boasts a wide variety of wetland types-both natural and man-made. The list below includes the types most likely to be encountered during amphibian surveys, but may not be exhaustive. Feel free to describe your wetland type if it does not fit the descriptions below.
- Found in East Texas, these are sites found on acid peat soils that are low in nutrients. They have essentially no water flow in or out. Vegetation includes low shrubs, herbs, and a few tree species, with the ground cover dominated by sphagnum moss. Some are very over grown with vegetation, while others may contain areas of open water.
- Ditches are obviously man-made linear wetland habitat, with a wide array of native and non-native vegetation. Despite their artificial nature, many ditches are used by amphibians as breeding habitat.
- Lakes are described as any body of water over 20 acres in size dominated by deep open water. Vegetation and anuran habitat is usually limited to the shallow areas along the shore. With only one natural freshwater lake in Texas, most lakes are actually man-made reservoirs.
- Marshes are any wetland characterized as maintaining water year round and dominated by herbaceous, non-woody vegetation. Water depths can vary but are not usually greater than 3 feet. Common plant species include cattails, rushes, sedges, and grasses, along with submergent plants in the more open water areas. In West Texas spring-fed marshes are known as cienegas.
- These are lakes smaller than 20 acres in size. Vegetation can vary, but anuran habitat is usually restricted to shallow areas near the shore. Please indicate whether natural or man-made.
- Found most frequently in East Texas, these wetlands are dominated by woody vegetation. Standing water is usually present year-round. Streams include a variety of wetland habitats from small, intermittent drainage's to large rivers in Texas. Anurans are most likely to utilize the edges of slow-moving stream bodies, but some salamanders are adapted to using deeper water (for example, amphiuma and sirens in East Texas streams) or faster flow areas (for example, the spring-dwelling Eurycea salamanders found in Central Texas streams). Streams should be characterized on the data form as intermittent, small (less than 15 feet in width), or large (more than 15 feet in width). Spring-fed stream habitat should also be noted.
- Temporary Pool
- This category includes "puddles." A temporary pool is defined as any non-permanent water body that is not part of a larger wetland complex as described above. Temporary pools most often result from spring rains, although they may occur in the summer and fall in West Texas.
- Wet Meadow
- These areas are dominated by grasses, sedges, and rushes and may appear prairie-like for most of the year. In areas with water-logged soils, however, water can stand during the spring and support breeding amphibians.