Update on Yellowstone Lake Cutthroat

August 4, 2011 Update for Save the Yellowstone Cutthroat

th. In addition to the two NPS boats that are gill netting on the Lake (which have now gone to a 6 day, double crew work schedule), a commercial gill netter from the Great Lakes region (the Hickey Bros.) has two boats on the Lake. One is strictly a gill netting boat and will work continuously until September 15th. The other contract boat is splitting its time between pulling 8 trap nets where large lake trout can be targeted even in the presence of YCT since fish are captured alive, and gill netting. The trap nets are significant because of where they can be placed and because they target large, spawning age lake trout. As of early August when this is written, over 120,000 lake trout have already been killed. The total will go significantly higher by season’s end.

The year 2011 has already witnessed major progress in the efforts to suppress lake trout in Yellowstone Lake (YL) and to restore this iconic Yellowstone cutthroat trout (YCT) population.

We are proud of this effort and Trout Unlimited’s (TU’s) Save the Yellowstone Cutthroat fund can use your help to carry this progress forward. The following is a synopsis of that progress and a look ahead to the direction of the efforts.

Late in 2010 a new Superintendent was named for Yellowstone National Park(YNP), Daniel Wenk. Superintendent Wenk began his national park career in 1975 and then was assigned to YNP in 1979. He later worked at Mt. Rushmore and the Denver Service Center. Daniel brought to YNP a strong scientific approach to solving the Yellowstone Lake fisheries issues and a willingness to work with outside interests including those of Trout Unlimited (TU) to assist in the effort. He also stated that the YCT fishery was one of his most important natural resources issues in the Park. As a result, significant progress on many fronts has been achieved. In March, members from WY TU, MT TU, the Greater Yellowstone Coalition and the National Parks Conservation Association met with new Superintendent Wenk where they were warmly greeted, listened to, and invited to be part of the solution on YL. He invited these NGO’s to enter into a Memo of Understanding (MOU) with Yellowstone to facilitate this cooperation.

In early 2011 the NPS also released their draft EA on Native Fisheries Conservation. The Plan was reviewed at open houses in Cody and in Bozeman with both meetings very well attended by TU members and supporters. In fact, a high percentage of the formal comments received (over 3000 total) were from TU members. The Plan has now been approved and is very significant in that it sets definitive goals for lake trout removal and for YCT recovery.

Specifically, the Park plans to reduce the lake trout population by 25% each year (a mortality rate of 0.56 each year); to restore the YCT population to an average of the 1995-1999 spawning numbers or 12,800 spawning fish into Clear Creek; and to maintain YCT spawning access to 75% of the known YCT spawning tributaries that are now blocked to varying degrees by gravel bars. These goals are lofty and will only be achieved through significant and scientifically sound approaches.

The lake trout suppression activities were immediately boosted on YL when the ice went off June 9

YNP also recognized the importance of scientific review of their work and reconvened the Science Review Panel that first met in 2008. This June’s meeting was extremely cooperative with all involved commenting on the fresh approach. Some of the highlights include (a) new population modeling which show that the current lake trout population to be around 300,000 to 400,000, (b) confirmation of the annual lake trout suppression targets of 50% to achieve population declines, (c) confirmation from the Lake Pend Oreille experience that a native trout population can recover with significant lake trout suppression especially targeting lake trout spawning areas, and finally, (d) the single most pressing scientific need on the Lake is a hydro-acoustic telemetry study to identify both lake trout movement patterns and their spawning beds. Identifying these spawning beds will both allow massive gill netting efforts as well as identify those areas where new lake trout ova and fry suppression technology can be employed. In addition, the Panel recommended that the Park ramp up the total gill netting effort to 57,000 units, the rebuilding of the Clear Creek weir to monitor YCT populations, and the formation of a Science Advisory Committee and a Financial Advisory Committee that each meet regularly. As you read in the last paragraph and will see in the next, the NPS has responded to many of these suggestions.

This past month has also signaled a major milestone in YNP. Dr. Robert Gresswell of the USGS, with the support and encouragement of the fisheries team in Yellowstone, has launched a hydro-acoustic telemetry study on Yellowstone Lake. This has been made possible by several groups coming together to make it happen. First, the NPS made $25,000 available to buy some of the telemetry tags and, in addition, donated man-power, equipment, housing, etc. to run the study; the USGS wrote the study plan and arranged for the loan of receivers that can be placed around the Lake to monitor the movements; and finally, the NGO’s committed to funding about one half of the telemetry tags ($27,000 from the Save The Yellowstone Cutthroat campaign of the East Yellowstone Chapter of TU) and to funding about $10,000 worth of travel costs and mooring hardware (MT TU, GYC, and NPCA). This cooperation is monumental and the study is huge for future success on the Lake. The actual study plan and 2011 budget can be reviewed at

Yellowstone Telemetry Budget 7-19-11 (pdf).th the hydro-acoustic tags (140 of them) will be implanted in adult lake trout taken from the trap nets. The receivers (26 of them) will be deployed at depth around the lake and monitoring will begin. As these lake trout move and especially as they congregate to spawn around the middle of September, their travel corridors and spawning beds will be located and confirmed. A portable receiver will also be deployed in a boat to further pinpoint these locations. This information should lead to more accurate gill net placements and targeting of spawning fish.Save the Yellowstone Cutthroat, PO Box 3008, Cody, WY 82414.

So, this leads us to the future. Around August 20

However, the study won’t end this fall. The hydro-acoustic tags have a battery life of three years so they will continue to “ping” for at least two more full seasons. The plan is to add 110 more tags next spring at a total cost of about $44,000 and possibly more receivers (24 more are desired) at a cost of $1400 each. Of course, support costs will also be required in subsequent years. Years two and three of the study will provide refinement and expansion of the data collected to be sure we have the entire system covered and all spawning areas identified.

The Save the Yellowstone Cutthroat fund can be proud that we are a major player in making this telemetry study a reality. Your contributions allowed us to purchase 73 hydro-acoustic tags at a cost of $27,000. Without your support, the study would not be happening.

However, we need your help as our financial commitments to aid in this valuable effort have just begun! To enable years two and three of the study, private individuals and groups are being asked to “buy” a single or multiple telemetry tag(s) at a cost of $400 each. Others can “buy” a receiver for $1400 each. Donations are currently being accepted at

If you value Yellowstone cutthroat trout in their native range, please consider making a donation to the fund.

We thank you for your past support and ask for your support in the future as we can now begin to see success on the horizon.