1.   And he said he is working on an agreement with tribes to mark all hatchery fish before release, starting as early as next spring.

2.   Aside from diluting the genetic identity of wild fish, hatchery fish can compete for food and spread disease.

3.   All the diseased hatchery fish had come from the eastern Maine stream, suggesting the outbreak began there.

4.   British researchers say the key to improving survival for hatchery fish is to send them on training courses to help them cope with life in the wild.

5.   But the dams, overfishing, destruction of spawning areas and the competition with hatchery fish cut severely into their numbers.

6.   But then the number of fish born in the wild reached a record level, at the same time the millions of hatchery fish reached a peak.

7.   Hatchery fish are more genetically similar to each other, and they are also more prone to mass disease outbreaks.

8.   It has cropped up most prominently in trout hatcheries and apparently spread into the wild when hatchery fish were released.

9.   Nevertheless, the growing reliance on hatchery fish raises questions about the long-term health of the salmon population.

10.   Only the oxygen-deficient upper portion received hatchery fish annually.