Appendix 5. Instructions for Van Dyke's salamander stream surveys. How to determine the distance between transect groups.

Groups will be spaced such that they will span the length of the stream in of the survey area, using a systematic placement based on time and area. Here s how to determine the distance (in your allotted 8 p-h) to put between the end of the last transect of a group and the beginning of the first transect of the next group (=intergroup distance):

1. Measure or estimate the linear distance of the main channel of the stream in m through the survey area (D) and record the length of time (to the nearest 0.25 h) it takes to complete your first group of transects (T).

2. Calculate the number of groups (N) that can be done within 8 p-h (a constant): N = 8/T + 0.25, rounded down to nearest whole number. The 0.25 h is added to account for potential underestimation.

3. Calculate the total distance of all groups (D₁). D₁ = N * 25.

4. Calculate the difference (D₂) between the total distance and group distance. D₂ = D - D₁.

5. Calculate the intergroup distance (I), in m. I = D₂/N-1. If I is zero or less, do not separate the groups; me+rely proceed until 8 p-h or the end of the area is reached.