The bulk of the work conducted by the fish and wildlife service on St. Paul revolves around seabird productivity monitoring. We have plots distributed throughout prime nesting habitat, that we visit on a rotating schedule every three days. For many hours, we sit on the edge of a cliff, and using either a scope or binoculars, note the status (i.e. bird, bird/egg, bird/chick, etc) of all the birds within the plots. We do, however, have side projects that add a little variety to our daily schedule. For instance today we are heading to a nearby pond to collect stickleback from traps we set yesterday. Stickleback are small minnow-sized fish found in both fresh and salt water systems throughout the northern hemisphere. Those that become trapped in ponds and lakes, like the ones here on St. Paul, make excellent subjects for studying evolution. Just like Darwin's finches, isolated populations of these small fish, unable to exchange genetic information with neighboring populations, have evolved different morphology on a relatively brief timescale. For example stickleback found in the ocean contain up to ten times more armor plating than those in fresh water systems. This is likely a response to predatory pressures, a heavier armor protects against fast moving predatory fish in the ocean, whereas a lighter armor, mostly around the head, makes the stickleback faster, and protects against slow moving predatory insects in fresh water. That's the gist of it anyway. Interesting stuff.
Canon EOS 60D, Canon EF 17-40mm f/4L USM, ISO-400 f/7.1 @ 1/125 sec.
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