Tuesday, October 26, 2010

Predator Conundrums

The last few weeks of the season at the lodge demonstrated to me how we as humans can let our emotions and meddling get in the way of Mother Nature's grand plans. As a demonstration project at the lodge, we have a fish hatchery. In this hatchery we raise coho salmon. Last fall we went out and caught a female and a male coho salmon from the river, stripped her eggs and fertilized them with his milt. All winter long they were incubated in the plastic incubator, safe from the ravages of predators and flooding rivers. This spring, once they were all "buttoned up" we placed them into the trough in the Interpretive Center where we fed them a large healthy diet of commercial fish food. By September they had grown to an average size of 4.5 grams, maybe 3 or 4 times the size of wild coho raised in their natural riverine environment.
Once we deemed the river had enough water after the dry season and the water temperature cooled down to be comfortable for the salmon, we began releasing them into a quiet pool in the Glendale river. 3200 coho fry were released with our best intentions and wishes for a safe journey to the Pacific Ocean and back in three years from now. This is our first instant of meddling with Mother Nature. Many people believe that hatchery raised fish should not be allowed as they have a very unfair advantage over naturally reared wild salmon fry due to their much larger size. The larger fry may have a bit of a setback until they learn where to find food in the river rather than having it dropped to them daily from above. They may also need to learn to watch for wild natural predators who are looking for a meal, especially large dumb fry. Once they become accustomed to their wild habitat, the large fry will begin to eat natural food such as insects, bugs and smaller salmon fry. That's right, they will be eating their smaller wild cousins who did not have the advantages that the large, human fed, fry have had. Humans first mistake even though we mean well. We believe that we are trying to help the river out by raising a few more fish who will grow up to be large coho, fun fish to catch on a rod and reel for our benefit. These fully grown coho also bring back nutrients from the ocean that will eventually feed the bears and the forest around the river. These are all valid, positive justifications for our interference, however we do not really know the true cost to the river. Are these behemoths eating more wild fry than we released, thereby resulting in a net loss of coho in the long run? We have no way of knowing for sure.
The next potential interference we noted was the predators of the wild coho fry. We watched as a Great Blue Heron sat in it's favorite fishing hole daily, snatching coho fry from their hiding spot in the shallows. Now I know that herons are having a rough time of surviving along the coast and are protected by law, but this murderous fish poacher was starting to bring my own style of western justice out of the self imposed mothballs. Henry would sit in front of we humans and brazenly catch wild coho salmon fry day after day, hour after hour.
He would only abandon his fishing hole if a grizzly approached too close for comfort, then he would croak his complaints about the injustices in his life, as he flew to safety in the alder trees above. Don't think I didn't wish I had a sling shot or a twelve gauge handy to protect the salmon fry. What was the use of all of our hard work raising fry only to be eaten by a fish poacher like Henry the Heron?
We got lots of discussion mileage out of this demonstration of the salmon's role in life. They are themselves predators put on earth to "eat and be eaten." It is their role in Nature's grand scheme: eat all they can and feed over 150 different species of predators during their short life. Along their epic odyssey, they will transfer their body weight of nutrients gathered from the open ocean back to their natal river where, they will procreate their species, then die, leaving their large rotting carcasses to feed the river, the bears and eagles and fertilize the forest.
Let us quit interfering in this perfect plan. Let us make it as easy as possible for the wild salmon to make their already dangerous journey, unimpeded by our meddling.

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