Normal 0 The Clarkfork of the Columbia River and most of its tributaries contained Western Montana’s best trout streams prior to the arrival of the white man. When the Berkley Pit in Butte, Montana began mining copper it was the beginning of the demise for the Clarkfork River. Years of smelting oar at the nearby town of Anaconda, Montana polluted the flood plains of the upper and lower Clarkfork River Basin with tons of toxic materials. These toxic materials have been distributed throughout the entire Clarkfork River Basin by years of spring run-off. Man-kind has been trying to clean up the devastated Clarkfork River for quite some time now; this is one of America’s largest Environmental Protection Agencies Super Fund Sites and our government agencies can not make a sound decision on how to clean up the river. Millions of dollars have been spent on constructing settling ponds, stream by-pass’s and the liming of the out-let water flowing from the settling ponds near the town of Anaconda to help restore but not permanently solve the real problems that exist with the Clarkfork River. These large deposits of toxic waste originate from the town of Butte, Montana continuing downstream to the Mill Town Dam; three miles east of the city of Missoula, Montana. With all the problems on the Clarkfork River I am amazed that there is still some excellent fishing in certain areas of the river system, however I would advise you not to consume any trout from the Clarkfork River; they are loaded with extremely toxic materials. Beginning in 1984 through 1987 I worked for the Montana Fish, Wildlife and Parks Department as a Fisheries Technician performing fish population estimates on most of the trout waters in Region #2 in Western Montana. I conducted trout populations on the Clarkfork River from Anaconda downstream to its confluence with the Flathead River near Paradise, Montana. I also conducted trout population estimates on the Clarkfork River Tributaries most notably: the Blackfoot River and Tributaries, Bitterroot River and Tributaries and Rock Creek. The fishable section of the Clarkfork River originates at the outlet of the settling ponds just outside Anaconda, Montana and flows northwesterly to the Idaho State Line. I will try to give a run-down on the trout populations throughout the Clarkfork River Drainage. The Clarkfork River just below the settling ponds is big fish water; these large fish have migrated through the ponds and entered the Clarkfork River system. These trout are predominantly Brown Trout and can reach 20-pounds, however most of the population consists of one to three-pound Brown Trout and Rainbow Trout from 1½ to 10-pounds. The Brown Trout population in this area varies from year to year depending on the quantities of heavy metals entering the river system each year from the nearby smelting tailings from Anaconda. Some years the trout population is only 1,500 trout per mile of stream and in other years it is as high as 6,000 trout per mile of stream. The Clarkfork River Brown Trout population falls off rapidly just a few miles downstream towards the town of Deer Lodge; to just 250 trout per mile of stream. However, there is a high concentration of Brown Trout at the Deer Lodge sewage treatment plant out-let. These Brown Trout are neon colored due to the high level of nutrients entering into the river from the sewage settling ponds. From Deer Lodge to the Little Blackfoot River confluence, the Clarkfork River Brown Trout population is around 250 fish per mile of stream. The Brown Trout population increases slightly in the Clarkfork River from the confluence of Little Blackfoot River downstream to the confluence with Gold Creek. Gold Creek downstream to Rock Creek the Clarkfork River streambed was altered when the Interstate 90 Freeway was built and the river was channelized and constructed with a constant gradient. The Clarkfork River Brown Trout population below the Gold Creek confluence with the Clarkfork River falls to just 25 Brown Trout per mile of stream until it reaches its confluence with Rock Creek. The Clarkfork River from Rock Creek downstream to Mill Town Dam and its confluence with the Blackfoot River upstream from the Dam the combined trout population increases tremendously to 1,500 to 2,000 trout per mile of stream. The Clarkfork River trout species composition also changes; this section of the Clarkfork River, Rock Creek downstream to the dam supports 55% Rainbow Trout up to twenty-two inches in length, 5% Westslope Cutthroat Trout up to twenty-two inches in length, 43% Brown Trout up to twenty-four inches in length, 1% Bull Trout up to thirty- six inches in length and 1% Northern Pike some over 40-inches in length. Mill Town Dam was built without a fish ladder; this barrier has decimated the historic Clarkfork River Native Trout runs; the Westslope Cutthroat Trout and the Bull Trout. The Clarkfork River trout population is poor downstream from Mill Town Dam to its confluence with the Bitterroot River at only 500 to 750 trout per mile of stream. This section of the Clarkfork River runs through the city of Missoula, Montana. Until 1974 it was legal to throw garbage off any bridge in Missoula into the Clarkfork River. One of the best Westslope Cutthroat Trout and Bull Trout streams in Montana flows into the Clarkfork River in the heart of Missoula, Rattlesnake Creek. The Clarkfork River trout population below the Bitterroot River confluence increases slightly to 750 to 1,500 trout per mile of stream and is maintained at this level downstream to its confluence with the Flathead River. The section of the Clarkfork River below the confluence of the Bitterroot River contains some of the hardest fighting and leaping Rainbow Trout you will find anywhere in Montana. The Rainbow Trout in this section can reach over 25-inches in length and weight over 10-pounds. Also this section contains the Native Bull Trout, which can exceed 20-pounds. Now an update to the Clarkfork River January 1st, 2011; in the spring of 2008 the Mill Town Dam was breached and all migrating trout species now had access to the Blackfoot River, the Upper Clarkfork River and their tributaries. When they breached the Mill Town Dam the trout fishery for miles downstream was devastated by all the toxins that were released and most of the trout species were killed.

When looking for a book on fish toxicology, you might find one that discusses the biochemical and molecular aspects, or one that focuses aquatic toxicology in general. You can find resources that cover human and animal toxicology or ecotoxicology in general, but no up-to-date, comprehensive monograph devoted to the effects of chemical pollution on