Ultraviolet lights — similar to the “black” lights used in discotheques — may prove a fatal attraction for cane toads (Bufo marinus).
The pesky amphibians were introduced into Australia in 1935 to help eradicate beetles that infest sugar cane plantations. In one of the more spectacular failures of biological pest control, the creatures became a greater plague themselves. Although having little or no impact on the beetle population, they went forth and multiplied rapidly, proving an environmental hazard, in part because they are edging out indigenous amphibians for survival, but, more importantly, because they are toxic. Venom that is stored in glands near the toads’ necks poisons the wildlife that feeds on them — including crocodiles, birds, fish and snakes — thus destroying the predators that might help keep them in check.
Australian researchers have been seeking a humane way to trap the creatures for many years. Experiments with red and blue lights didn’t work, but it seems that UV lights finally may do the trick. The researchers say that it could be that these lights attract swarms of insects that entice the toads. In any case, the lights, placed in traps with one-way doors, have already “captivated” hundreds of toads.