When Night Falls / by Michael Johns

Somewhere between four and nine thousand ashy storm-petrels breed on Southeast Farallon Island, roughy half of the world's population. These sparrow-sized seabirds are tiny versions of more familiar open ocean wanderers like shearwaters and albatrosses, and like their relatives they brave extreme oceanic storms in a truly pelagic lifestyle. Ashy storm-petrels only arrive on colony after dusk and depart before dawn, and are almost never seen on island during the day. So in order to study this species, you have to forgo normal working hours and venture out into the field at night. During lulls in the spring winds, we head out just before 10PM to suitable storm-petrel breeding habitats and set up a long wall of fine mesh netting called a mist net. Calls of ashy storm-petrels are played with a loud speaking near the net to attract unsuspecting birds. Storm-petrels caught in the mist net are then measured, weighed, and banded with a small metal numeric leg band before being released; part of a mark-recapture study aimed to arrive at a more accurate estimate of the breeding population on the Farallones. Along with the joys of working with such an incredible seabird species, on clear nights we are also treated to a dazzling display of our own galaxy.