A reliable, non-invasive technique for measuring growth in tadpoles exposed to salt

The use of chemical de-icers raises salt levels in roadside streams and ponds, which has adverse effects on tadpole development. Experiments on the effects of de-icers on tadpole development are often hampered by difficulties measuring body size without introducing handling stress that may skew results or cause unintended mortality. We have found a linear relationship between surface area and body mass in tadpoles that is unaffected by exposure to salt. Measuring surface area is therefore a suitable technique whose use should be encouraged when investigating the effects of salt exposure on tadpole growth and development.