DRIFT FENCE-ASSOCIATED SAMPLING BIAS OF AMPHIBIANS AT A FLORIDA SANDHILLS TEMPORARY POND

Five years of field observations suggest that amphibians inhabiting a sandhills community are able to circumvent a drift fence-pitfall trap enclosure as they move toward and away from an ephemeral pond. Trespass rates varied depending on species and showed no tendency to increase or decrease as the study progressed. Laboratory trials confirmed that frogs easily crossed the fence by walking up the side or hopping over it. Frogs crossed the fence readily regardless of sex or whether the frog was an adult or juvenile. Although striped newts did not climb over the fence in the laboratory, they may use tunnels to go under fences under field conditions. Other species may burrow directly under the fence. A priori assumptions about a species' ability to climb a fence, or that trespass rates do not vary temporally or among sites, are unwarranted and may lead to misinterpretations of the results from studies using drift fences and pitfall traps.