Restoration & Rehabilitation
Fri Apr 20 10:25:00 MDT 2012
Surveys in the headwaters of Crawford Creek in 2003 documented the presence of a small population of pure native westslope cutthroat trout (WCT) above a waterfall barrier. Downstream Crawford Creek supported brook trout and hybridized WCT trout. A barrier was constructed on lower Crawford Creek in 2005. In 2006, approximately 1.5 miles of Crawford Creek upstream of the constructed fish barrier was treated with rotenone (EA 5/16/2006; DN 8/28/2006). A total of 196 live juvenile and adult WCT were transferred in 2007 and 2008 to the fishless habitat in Crawford Creek. Surveys in 2009 found rainbow and hybrid trout above the fish barrier. The Lewis and Clark National Forest identified a road crossing and culvert replacement project 0.10 miles downstream of the current failing fish barrier and was designed to meet requirements of both the USFS and the stringent criteria for a fish barrier. We propose using rotenone to remove hybridized fish from the lower reaches of Crawford Creek (1 to 1.5 miles of stream) after replacement of the old and inadequate culvert with the new culvert/fish barrier. Non-hybridized WCT remaining in the headwaters of Crawford Creek would then naturally re-populate the lower reaches of stream. The proposed action is nearly identical to the selected action described in the original EA (EA 5/16/2006; DN 8/28/2006). Under the proposed action, approximately 0.10 miles of additional downstream habitat would be treated with rotenone. Only the length of stream supporting non-native fishes would be treated. Non-hybridized WCT may currently occupy the headwaters of previously treated areas of Crawford Creek. These headwater areas would be assessed and eliminated from treatment plans. The level of environmental and human impacts described and addressed in the original EA are essentially unchanged. We also describe the two other alternatives considered. The proposed alternative would increase the total miles of stream holding non-hybridized WCT by approximately 5 percent in the Belt Creek Drainage.