aquatic surveys




Table 1. Trapping data and coefficient of variation estimation. Traps were haphazardly spread over a homogenous habitat in two wetlands. The CV was calculated using all means (to include intra-annual variation) and using only one date per year (marked with asterisks).

Bell Marsh, Fort Lewis, Washington:

Date

CV

Species 6/27/94* 7/5/94 6/5/95 6/22/95* 7/5/95 7/6/95 6/7/96* Ann. Intra-Ann.
Traps Set 4 10 5 10 12 12 5
Rana

aurora

mean 19.75 27.3 4.2 5.9 3 2.417 2.8 95% 107%
std. dev. 7.274 14.788 4.266 2.378 1.651 1.832 1.095
range 13-29 9-52 0-10 1-9 1-6 0-6 1-4
Hyla

regilla

mean 0.75 1.3 4.2 8.1 2.667 3.583 0.6 136% 86%
std. dev. 0.957 1.567 3.899 6.244 3.143 2.021 0.894
range 0-2 0-4 0-8 1-23 0-9 0-7 0-2




Lost Marsh, Fort Lewis, Washington:
Date CV
Species 6/23/95 7/3/95 7/4/95 Intra-Ann.
Traps Set 18 18 18
Rana mean 1.16 0.611 0.389 55%
aurora std. dev. 1.098 1.145 0.698
range 0-4 0-4 0-2
Hyla mean 19.667 7 13.611 47%
regilla std. dev. 6.624 6.508 9.9
range 8-36 0-27 1-32
Ambystoma mean 2.722 2.167 0.722 55%
macrodactylum std. dev. 1.565 2.572 0.958
range 0-5 0-9 0-3



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