Roads create many challenges for conservation, and amphibians are particularly vulnerable to their negative effects. This experiment evaluates the impact that traffic noise has on amphibian populations, specifically anurans (frogs and toads). It is thought that traffic noise may act to reduce population abundances. However, it is difficult to disentangle the impact of noise from other road effects, such as roadkill and chemical pollution. To test this, we created a "phantom road" by playing different traffic noise treatments in four roadless areas and measured resulting anuran abundance, testing whether anurans avoid traffic noise.
Results/Conclusions
Preliminary data showed no effect of traffic noise, but strong effects of date and site. We believe this may reflect a limited ability to maximize sampling effort during periods of greatest frog calling activity (rain events), and we have accordingly implemented methods that will greatly increase data collection, including deployment of acoustic recording devices. In addition to our preliminary results, we plan to also present the results of 5 months of acoustic monitoring (March-July 2016), with robust conclusions about whether traffic noise truly reduces anuran abundance.