Turned out, Picaridin (chemical pesticide found in many insect repellents) not only repells mosquitos, temporarily comforting consumers but also kills predators like salamanders that control the populations of mosquitos, hence permanently increasing the number of mosquitos in the habitat. What a clever idea! Spray Picaridin bug spray to get rid of bugs, then go back to the store and buy more since the number of mosquitos will increase.
By harming mosquito predators, picaridin may help mosquitoes survive
“Insect repellents containing picaridin can be lethal to salamanders. So reports a new study published in Biology Letters that investigated how exposure to two common insect repellents influenced the survival of aquatic salamander and mosquito larvae.
Insect repellents are a defense against mosquito bites and mosquito-borne diseases like dengue, chikungunya, Zika, and West Nile virus. Salamanders provide natural mosquito control. During their aquatic juvenile phase, they forage on mosquito larvae, keeping populations of these nuisance insects in check.”
Emma Rosi, a freshwater ecologist at Cary Institute of Ecosystem Studies and a co-author on the paper explains, “Use of insect repellents is on the rise globally. Chemicals in repellents enter aquatic ecosystems through sewage effluent and are now common in surface waters. We set out to understand the impact of repellent pollution on both larval mosquitoes and the larval salamanders that prey on them.”