Bird kills highlight threats of noise pollution

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What do blackbirds and whales have in common? A potentially fatal tendency to over-react to loud noises.
Massive and somewhat mysterious bird and fish kills around the globe have ignited conspiracy theories and cries of “aflockalypse.” A quick perusal of the US Geological Survey’s database of wildlife mortality events shows that such events are not as uncommon as one might thing. And, as causes for the individual events are pinned down, it’s becoming clearer and clearer that recent events are unrelated, with the fish kills linked variously to cold water and disease and the bird deaths attributed to fireworks. Interestingly, it’s the birds that sparked an ocean connection for NRDC’s Michael Jasny:
Now birds and whales are vastly different species, with different ecologies, but the die-off in Beebe couldn’t help but make me think of the oceans and the growing problem that marine wildlife is facing from disruptive, manmade noise. There certainly are limits to the comparisons you can draw, but the reactions of birds, which are generally far easier to study, can shed some light on marine animals and how they are adjusting or failing to compensate for the urbanization of their world.
One thing we can say about the blackbirds’ behavior in Arkansas is that it was maladaptive. The birds weren’t in any direct physical danger from the fireworks, and by tearing off into the dark sky they put themselves at risk of collision and death.
But the “fight-or-flight” response, which is highly conserved across species, doesn’t always lead to the best results. Take for comparison the melon-headed whales caught in a naval sonar exercise off Hawaii, in 2004. The exercise seems to have herded a large pod – representing a significant part of the melon-head population – towards the main islands and around Kauai, where they wound up stranded for two days in Hanalei Bay and might well have died were it not for a brilliant local rescue.
In the end it would have been better for the whales to have braved the Navy’s high-intensity sonar signals than to have fled, just as it would have been better for the blackbirds to have stayed put as the fireworks boomed around them. Sometimes it is just hard to deny the primal urge to run.


