Sunday, February 11, 2018

The Fish Trap


On a cold Saturday morning, we struggle into the constrictive, clammy confines of our waders and begin the trek down the hill to our fish trap. We’re trapping the Arroyo Hondo. Situated in eastern Santa Clara County, this creek spills into the eastern edge of Calaveras Reservoir, in the outskirts of Milpitas and a Silicon Valley, virtually oblivious to the untrammeled wilderness with which it rubs elbows. I am accompanied by our brand new intern, who happens to have exactly one day more of experience at the new fish trapping site than me. It is with considerable trepidation that I recognize the possibility that there might be a trout in the trap. Sure, last summer I had PIT tagged a few trout, but only small ones that fit easily in the palm of my inexperienced hand. Certainly, none of the hogs that had been popping up in the trap in the last couple of days. Nerves twanging, I set about filling out the data sheet, arranging gear, reviewing protocols. It’s all mundane, routine. Right?

We stuff a burlap bag into opening of the live box, so the trapped fish can’t escape, unlatch each of the six bolts that secure the box, and raise the lid. Whoosh! An angry tail whips creek water over the rim of the live box. Not one, not two, but three big rainbow trout hunkered down in the cool waters of the Arroyo Hondo, waiting to be weighed, measured and fitted with a tracking tag. Damnit! I’m not ready for this. So, buying time, we use small nets to scoop out willow catkins that have accumulated in the live box, and transfer the ho-hum prickly sculpin and California roach so routine to fish trapping from the live trap to a plastic bucket.  But there is no ignoring those three, enormous trout that need to be sedated, weighed, measured, PIT tagged and scale-sampled.

At some point it can’t be postponed anymore, so I fill the buckets with appropriate amount of creek water, add the baking soda and Alka Seltzer that will deoxygenate the water and stun the fish, and net the biggest trout. It struggles as I lift it from the live trap, splashing cold water into my eyes and hair. It tries to escape from the bucket, thrashing turbulent sheets of water from the anesthetic bath. This isn’t going to be easy, is it? I watch nervously as the big fish continues to disturb the water. But the protocols don’t lie. Four minutes later it repeatedly rolls to its side and surfaces to gulp for air. It is time. I’ve already weighed it, so I plunk it on the measuring board. 490 millimeters. Woah.  

I show our intern how I want it oriented, so I can place the PIT tag correctly; starboard side up, tail pointing away from me. Thank god, she has a natural feel for this, and the fish is tired, sedated. It goes well. The tag injector pops through the skin effortlessly, I pull the trigger, extract the gun, rub the incision, read and note the tag number. Not out of the woods yet though, scale samples are still needed. I retrieve the tiny pocket knife from our gear bag, unsheathe the blade, and laboriously scrape exactly one scale from the exposed side of this monster. I wipe the knife on the contact paper, and place the scale sample the labeled envelope. Done. Carefully placing this beauty in the recovery basin, oxygen bubbler merrily churning out air, I take a breath. A breeze floats down the Arroyo Hondo and cools the sweat on the back of my neck, raising goose bumps on my arms. I lift a second fish from the trap. Weigh, measure, tag, scales. Repeat. This, is what I do.