Welcome‎ > ‎News‎ > ‎

Over 46,000 Triploids Released

posted Mar 30, 2017, 7:48 AM by cct fishtags   [ updated Mar 30, 2017, 7:50 AM ]

The Colville Tribes Resident Fish Hatchery released of over 46,000 triploid rainbow trout into Rufus Woods Lake on March 23, 2017. The fish average almost 2 pounds each and can be identified by the absence of an adipose fin. Currently, anglers have been very successful, and they are encroached to take advantage of this fishery the department has provided while it persists. Higher than expected stream flows, dam maintenance, and drawn down requirements forced Grand Coulee Dam to spill water from spill tubes which increased total dissolved gas (TGD) levels >120%. Studies have shown that TDG levels of 120% cause gas bubble trauma to Rainbow Trout which can cause approximately 20% mortality.  As TDG level and exposure time increase, fish are subjected to higher mortality rates.  Since increased TDG levels are anticipated in the foreseeable future due to high river flows and dam operations, these fish were released earlier than originally scheduled.