Insectivorous bats provide significant economic value to the Australian cotton industry

Abstract

<p>Insectivorous bats exert top-down pressure on pest insect populations in agricultural systems globally. However, few economic estimates exist of their value as pest control agents in many high value crops. We calculated the economic benefit of direct predation of insect pests by bats and the damage averted to cotton yield, a high value commodity crop in Australia. Using a combination of bat dietary studies, average daily energy requirements (estimated by field metabolic rate), prey energy content and acoustic data of bat feeding attempts in cotton crops, we show the direct value of insectivorous bats to the Australian cotton industry is likely between $99-126 ha^-1 in dryland Bt-cotton and $286-361 ha^-1 in irrigated Bt-cotton through the consumption of pest moth <i>Helicoverpa armigera</i>, amounting to $63.6 million annually. We estimate that a population of bats can remove between 77-119 t of moths from Australian cotton crops in an average year across the growing season. However, different bat species consume different insect pests, highlighting the need to conserve bat diversity in agroecosystems. These results provide further incentive for growers to manage non-crop bat roosting habitat to benefit from natural pest control in crops.</p>