They quickly adjust their helmets, harness themselves into rock climbing ropes and ascend the slick sides to make room for the next jumper. Some 350 adult murre decoys stand at attention as piped-in murre music carries across the cove. Some 350 adult murre decoys stand at attention atop the island. Though they do not move, it sounds as though they are calling and loudly as piped-in murre music carries across the cove. Parker recorded a murre colony on the Farallon Islands, west of San Francisco, and now loudspeakers blare the colony's chorus perpetually.
Solar panels fuel marine rechargeable batteries to keep up the din.
Murres make squawky, croaky calls. When they're really excited, it sounds like they're playing the kazoo. In between the solar panels and decoys, twelve mirrors are propped up so that arriving murres will see their reflected movements. Otherwise, the colony would look a bit unconvincing, even to a murre. The scientists remove the whitened decoys at the end of each breeding season to scrape off all the guano.