September 2, 2013 Coyote Hills Regional Park, Union City, California
Alameda Creek flows in a culvert leading from the East Bay ridges to San Francisco Bay. The area is parched; dry heat pounds on Kate and me as we streak along the bike path We pass spots where patches of water welcome birds. One white pelican swims alone; sand pipers scurry around the muddy riverbank.
Coyote Hills Regional Park’s marsh is surrounded by grassy hills that turn golden in late summer. Flocks of white pelicans circle the wetland. They nearly vanish as they circle away from the sun, then reappear when direct light hits their dark wingtips. Dozens more swim, dipping their long beaks to catch fish. They ignore the stunned kids and parents who stop to photograph them. Three stand on a small island, surrounded by cat tails. They’ve caught their share of fish, and deserve a break.
“Those look like alligators,” Kate says, and points at long flapping creatures near the marsh’s shore. They are a few feet long and squirming; they’d blend in with the muddy bottom if they were still. For a moment, we think they’re river otters, but quickly realize they have scales, not fur, and they’re not lifting their heads above the surface for a breath.
“Carp,” a park naturalist tells us later. “They’re an introduced species here.” He’s busy selling books and granola bars in the nature center, so we don’t pester him for more information. It’s obvious from his expression that these intruders are a problem. Invaders like these eat more of their share of local animals or plants; there’s often no predator that can control their population. I can’t imagine what might prey on the carp; they’re even too big for the huge white pelicans.
We leave the park after our short conversation with the naturalist. Barn swallows and violet green swallows streak above the water, changing direction every second as they chase insects. These little birds will head south when autumn’s cool weather makes their prey scarce. Three northern shovelers drift past, scooping the water with their long, flat beaks. These ducks are early migrants from the north; the marsh will fill with their relatives as winter comes. These birds are welcome. Still, we’re left with the constant dilema – we love the earth while we see its wounds.