Hermit crabs are just the latest animals shown to alter their behavior in the presence of noisy humans.
- Boat noises are shown to distract hermit crabs from looking out for danger.
- Birds have shown to change their songs when in loud settings.
- Scientists are just starting to study the effects of an increasingly loud world on animals.
Hermit crabs don't send text messages while scurrying, but human technology may be distracting them all the same.
When boat noise roared over a beach, the crabs weren't as quick as usual to hide inside their shells to avoid a potential predator, says behavioral ecologist Daniel T. Blumstein of UCLA.
The boat roar may not be masking the sound of an approaching predator so much as distracting the crabs from looking out for danger, Blumstein and his students propose in an upcoming Biology Letters.
Distraction makes sense, they contend, because boat noise had an effect even during tests with a mock predator that made no noise to mask. For a silent menace, the researchers used poles to swing a black T-shirt covering an inflatable doughnut toward the crabs. Without boat noise, hermit crabs popped back into their shells briskly as the scary shirt drew near. During a boat roar, though, the crabs didn't respond as quickly, the researchers report.