A global survey on acoustic bat lures highlights ethical concerns and the need for standardised methods

Acoustic bat lures are devices capable of playing high frequency sound. These stem from research showing the behavioural responses of bats to acoustic stimuli, and are used as bat-attractants, usually in an effort to catch bats. Through an online survey, we aimed to inform best practice by accumulating user experiences. We received 55 responses to the survey from 21 countries. Lures have been used across 34 countries, but predominantly in the United Kingdom, across the European Union, and throughout the USA during bat community-focused surveys. With growing research that lures may attract some species whilst deterring others, lures may be more appropriately used for species-specific focused projects, rather than broader, bat community-focused projects. Over half of survey respondents expressed ethical concerns surrounding the use of bat lures, stating that their use should be limited due to a lack of understanding of their effects, and that they may alter the behaviour of bats due to stress. We encourage practitioners to use lures with some caution, and test their utility so that over time we understand these potential concerns with more certainty. To this end, we also recommend guidelines be published for general ethical use, alongside standardised methods to deepen our future understanding of these devices and their effect on bat species globally.