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Brown Treesnake counts during visual encounter surveys at three walking paces, Guam 2016

June 1, 2020

We evaluated three walking paces to estimate (1) how snake detection rate per unit distance changes with increasing pace, and (2) how total number of snakes found by the end of a night of surveying varies with pace when the amount of surveying time per night is held constant. For a ?fast? pace we searched the 220 meter-long transect in 10 minutes, corresponding to a walking pace of 1.32 km/h, whereas for a ?medium? pace we searched 17.5 minutes, corresponding to a pace of approximately 0.75 km/h. The ?slow? pace was the 30 minutes (0.44 km/h) the standard previously adopted for work on Guam. Perch height and sizes of detected snakes were recorded for the three paces.