Chromosome numbers: A very interesting point. Actually, this subject was what first turned me on to fish genetics and prompted me back to grad school from a stream survey job with CFG. Thorgaard (WSU) has published much on the distribution of chromosome numbers in steelhead populations. He has demonstrated a high degree of intrastrain variability, on both systems with and without introduction from outside populations. As an example, a sample of Quinalt steelhead was found to have fish with both 58 and 59 chromosomes. The Rogue, with no introductions from outside systems, exhibits 2n numbers of 58, 59, 60 chromosomes. as does the Alsea. There are many more examples, and I know this first hand 'cuz I've spent many days of my graduate career counting chromosomes in Gary's lab!

I'd like to quote from a "lost" publication from a meeting held in Arcata in 1977 on steelhead management. (1977!!!)

"There are generally only two attitudes toward the implications of the use of hatcheries in steelhead enhancement and management programs which unfortunately divides those interested into those for and those against. The differences in opinion reflect a lack of knowledge as well as a lack of understanding of hatchery objectives."

I think that everyone even remotely connected to this issue would intuitively know that hatcheries cannot solve all manner of management problems. But how can we state that they are the cause of all evil? Previous hatchery programs have no doubt made grievous errors by indiscriminantly planting fish from wherever surplus eggs were available. But others are equally wrong when they become so righteous as to call hatchery management programs unjustified and bent on destroying all runs of native fish on behalf of the "Water Nazis" (whoever they are).

I've worked as a professional in various aspects of fisheries for many years, and I know that in general biologists, hatchery personnel, and sportsmen are reasonably knowledgeable about fisheries (this board is a great example). That said, we are left with the obvious conclusion that differences of opinion regarding the potential of hatcheries are based upon a lack of understanding or mistrust. I'd have to pick the former because we are all above holding petty mistrusts in the name of saving our fisheries (? )

Many arguments that I've read here suggest that a high degree of adaptive genetic variability is essential for the success of native stocks and that this variability is maintained by natural selection. The latter is extremely difficult for me to accept, since selection is (as mentioned by many here) a very powerful force. This force, however, does not cause variability, but instead is one that favors uniformity. Additionally, the common belief that hatchery rearing reduces genetic variation has simply not been proven when good practices are followed. The challenge becomes one of applying basic animal breeding concepts (common sense) in propogation efforts in such a a way as to: (1) enhance or maintain the fishery in a desired direction (not simply increasing numbers of fish), and (2) conserve, to the greatest extent possible, the genetic diversity of the species. By utilizing well-designed breeding and rearing programs we can capitalize on the changes that ALWAYS occur no matter what type of system we speak of by directing those changes to benefit the entire fishery cycle rather than just the hatchery phase.

As for the genetic identity of populations and stocks or strains, when I started in this business the idea of gene frequency analysis through protein electrophoresis was first being utilized by Fred(s) Allendorf and Utter. Allendorf described three major population groupings of rainbow trout (Upper Columbia R and Fraser R., west slope of the Cascades poulations, and "red band" populations. It was presumed that the inland group (upper C&F rivers) descended from a common ancestral stock that migrated to a large inland basin and was isolated during the last glacial period (10K years ago) while the coastal group represented descendants of Asiatic or American coatal population that existed beyond the range of the glacial mass. Now, with much more refined molecular tools, we speak of resolving differences down to the nearest 100 m of a river system. But what on earth do these differences mean evolutionarily? The limit to which genetic differences can be used to define natural populations of steelhead varies according to the amount of straying (or introgression) and/or isolation. The usefulness of defining two spawning populations occupying adjacent areas of a particular drainage on the basis of molecular markers is IMO ridiculous unless geographical or physiological barriers exist that preclude long term gene flow between them.

Sorry guys, gotta get to work here or I'll soon have all of my days to be posting and no chance of those days on a tropical sea. Looking forward to more discussions, but gotta say the personal attacks are way out of line.