An Entirely Synthetic Fish
Now this is not your average angling or fly-fishing book and definitely not a how-to or where-to book for the fly-fisher. But I still find it a very interesting book seen from an angling perspective because it deals both with the fishing culture and the fishing biology - and to a large extent also with fishing history and fishing politics.
It's the fascinating and somewhat repulsive story about the way the rainbow trout was taken from its home waters along the US side of the Pacific rim and spread literally all over the globe. Spreading a species like this has been done both before and after - both brown trout and other fish as well as mammals (rats, rabbits, cats, dogs, pigs) and invertebrates such as mussels, jellyfish and snails have been transported to remote locations on purpose or by random chance - but the rainbow's journey seems to be very well documented both historical and scientifically and the implications on fish farming, economy, and recreational fishing and influences on native species has been followed closely in north America especially and has drawn the attention of fishing organizations, politicians, scientists and historians.
Since it has also spread to most other parts of the world this history is not only interesting to Americans, but also to most of the rest of us. A friend of mine caught an escaped sea-farm rainbow in the Danish ocean just days ago in waters where rainbow trout is very far from natural, and we have these escapees regularly and in such great numbers that it definitely has to influence the local species as well as the aquatic environment.
Anders Halverson, an aquatic biologist from Yale University in the US, tells the story in great detail and based on very thorough and well documented research. This is as I already said, not your average anglers' book, but a full bred scientific work, but with a high degree of relevance to concerned anglers.
I called the story somewhat repulsive in the intro to my review, but that might not be quite fair, because when this story starts back in the early to mid 1800's, the world wasn't quite as wise on the results of widely spreading different animal species to places where they don't belong. We still ever so often seem to get surprised by what happens when foreign species suddenly wreck havoc on native ones, but there's a higher level of consciousness and knowledge about these matters now than back then.
Halvorsen tells about the first steps towards farming rainbows and stocking rivers and lakes by bringing out fertilized eggs and small fish by train and horseback back in the late 1800's and early 1900's and the more drastic methods of areal stocking (yes, dumping fish from planes!) over mountain lakes hitherto totally devoid of fish in the post WWII era.
He also accounts in great detail of the many both positive and negative results of these activities. Anglers did get some feisty fish to catch, but local species - both gamefish and less conspicuous fish - would often suffer dramatically and sometimes get driven to the edge of extinction in waters where rainbows were stocked.
In many places the drill is now one of trying to remove the rainbows and reinstating the native species, while other places have adapted the rainbows as the natural fish to stock and catch.
Meanwhile the rainbows have spread literally worldwide, and in my own home country, Denmark, they can be caught in the wild in streams and ocean as a result of fish escaping from fish farms in both fresh and salt water, and they are by far the most common fish to stock for catching in what we refer to as put-and-take fisheries. The natural Danish trout is the brown trout (AKA the German brown trout, salmo trutta), and to my knowledge there is little scientific research done to clarify the effect of the escaped fish on the wild, self-reproducing, native fish here. The only fairly clear fact is that brown trout both in streams and ocean aren't doing quite as well as they used to.
Halvorsen's book is very thought provoking because it so clearly lays bare the results of the sometimes mindless stocking of rainbows. It concentrates on north America and the author explains in depth what was done then to spread the fish and what has been done (and not done) since to limit the spread and even remove the rainbows.
It's a scientific book, well documented through literature and interviews and with an impressing index of the sources quoted. I was quite surprised when I got to page 188 of 256 and found that the text ended and the index of sources and keywords started. A dire list of precise references is the telltale sign of a genuine scientific work.
I can warmly recommend this book to anyone who wants to know more about man-influenced fishing biology, but will have to warn the average fishing book reader that it takes some stamina to read and probably a slightly scientific heart and brain to appreciate the full value of the content.
But I truly enjoyed the book, which has enough recreational fishing relevance and lots of historical facts and anecdotes to make it interesting to many anglers.