March 30, 2010 3:03:00 PM
I know little about fish or fishing, but I know fisherman like to go for rainbow trout, a good fish to have at the end of your line or to have in your frying pan. The rainbow trout is found all over our nation, and stands for conservation, and unspoiled waters, and the bounty of nature when nature is not trammeled by humans. Except that it does not really stand for any of these things.
Maybe fisherman know all about this already, but for me, the revelations in "An Entirely Synthetic Fish: How Rainbow Trout Beguiled America and Over-ran the World" (Yale University Press) were a surprise. The author Anders Halverson is a journalist, and has a doctorate in ecology, and likes to fish. He has hunted all through historical documents of government and conservation organizations, and interviewed plenty of researchers and others who have helped make the rainbow trout ubiquitous, or who are now trying to reduce its range.
This is not just a fish book. It is a carefully written history of how we think about our natural resources, and about the paradoxes and dangers of trying to control the natural world.
Rainbow trout are native to waters feeding into the Pacific, in an arc that extends up from northern Mexico, though the northeastern states, and over to far eastern Russia. That doesn''t matter anymore.
They have been introduced to the Atlantic states, and in fact to every state. The only reason they aren''t in Antarctica is that there is a lack of trout streams there; they are now on every other continent.
Halverson writes, "The range expansion that corn, sheep, dogs, and humans only achieved over thousands of years, rainbow trout have accomplished in a little more than a century."
A century ago, American fishing gentlemen were convinced that standing by a stream with rod and line was going to maintain our citizens'' virility and make our democracy stronger, but fish like the eastern brook trout were not able to withstand the pollution and higher temperatures we were inflicting on our streams. These men shunned the bottom-feeding catfish. They simply needed a better trout, and the rainbow was it.
Rainbows fought hard when caught, they withstood a bit of pollution and elevated temperatures, and they did well in hatcheries. In the nineteenth century, many nations were interested in acclimatizing their own species to different parts of the world; American acclimatizers liked the idea of getting this American fish all over American streams.
Not only could the rainbows fit within plenty of American streams, not only could they could go international, but they could be molded. Hatcheries could breed for rainbows that grew faster and matured earlier. They could be bred to mate at different times of the year, or selected for resistance, color, shape, and pugnacity at the end of the line. It was a 1939 report from the head of the government''s fish culture effort that bragged that they could now produce "an entirely ''synthetic'' fish."
The states with streams to be stocked thought this was all dandy. A recent report from the U.S. Fish and Wildlife Service says that if you spend a dollar on growing and stocking rainbows, you can expect $32 back in hotel reservations, rod sales and airplane tickets. The more the states stocked the streams, the more demand there was for rainbows.
The demand was enough that some hatchery trucks had sirens on them; they would dump full-grown rainbows into a stream and sound the "come and get ''em" siren for fishermen who would be pulling them out moments later. Sometimes a truck would not do; fingerlings dropped by an airplane sometimes survived the fall into the water better than those that had bounced up a trail on the back of a mule (although if the bombardier missed, the fish might wind up in the trees).
Everyone knows (now) that if you move a species into a region in which it did not evolve, you are liable to change things in unexpected ways. Think of rabbits going to Australia, or kudzu in our own South. The rainbows, as popular as they are with fishermen, are not popular with bats.
How can rainbows affect bats? It is simple: they gobble up mayflies and other insects that would otherwise be bat food. This has bothered songbird populations, too. The rainbows are also adept at eating native fish, and at feeding on frogs, which don''t need any other pressures these days.
Though rainbows were often imported with the idea of adding their diversity to the local fauna, they have decreased such diversity overall. The U.S. Fish and Wildlife Service has acted intentionally to decrease the diversity so that the rainbow trout could prosper.
In 1962, the service deliberately poisoned sections of the Green River in Utah and Wyoming with "piscicide" to get rid of the pesky fish that lived there naturally. There were some complaints by academics and ecologists at the time, but the chemical got dumped in the river, and the antidote that was supposed to be dumped downriver to neutralize it and keep it from heading on through National Parks properties didn''t get there, and so there was even more of an ecological disaster. This was made worse as a public relations matter because three weeks later Rachel Carson''s Silent Spring was published, infuriating some constituents who would not let their representatives in Washington hear the last of it. There were four species of "trash fish" that were to be killed to let the rainbows in; all are now on the endangered species list.
Halverson''s book, however, is not shrill about the many preposterous and presumptuous tinkerings with the environment that have been done for the sake of bringing more rainbows to our streams. There are few villains or fools in this story of the century since this unnatural fish has been taking over the world''s fresh water systems. Many of the public servants profiled here, whether their decisions were good ones or not, were taking steps based on the best information they had at the time, with the intention of helping anglers, and with no prospect of making any material gain by their actions.
Halverson tells many connected stories here in a convincing and fascinating book, and generally refrains from making judgments or regrets. There are inherent paradoxes anytime humans try to take control of nature. Fishermen may think that they are escaping from civilization by getting back to nature to pursue their prey, but it turns out the fish that many are pursuing are mere products of industrialization after all.
Rob Hardy is a local psychiatrist who reviews books for a hobby. His e-mail address is firstname.lastname@example.org.