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Take care of the fish, and the fishing will take care of itself.
Copyright 2014 East Yellowstone Chapter Trout Unlimited. All rights reserved.                                                          P.O. Box 3008, Cody, WY  82414
Background - Yellowstone Lake /Yellowstone Cutthroat Trout Status  January 3, 2012
The Problem:
The Yellowstone cutthroat trout (YCT) now occupy less than 43%
of their historical range; in addition, they are significantly
hybridized in 1/3rd of the remaining.

The Yellowstone Lake/upper Yellowstone River system (YL) was
once home to an estimated 4,000,000 YCT.  It was considered a
stronghold for genetically pure YCT’s and was considered
relatively safe from the impacts of climate change.  In addition, it
was considered a Keystone species for the entire ecosystem; 40
other species are dependent on YCT.
Lake trout (LT) were officially discovered in 1994.  They are
overwhelmingly the most significant threat of the triple threat to YCT
subsistence:  lake trout, drought, and whirling disease.

The NPS has been employing gill netting since 1995 and currently
spend $1M annually on the effort.  To date a total of over 800,000 LT
have been netted; 220,000 in 2011 alone.  The LT population is now
estimated at 3-400,000 adult fish.
The current YCT population is unknown; but is certainly no more than
10% of historical, probably <5%.
The Solution:
The YCT population in this system cannot be lost; and need not be
lost.  A Scientific Review Panel in 2008 made 4 major
recommendations to NPS.  These were renewed in June of this
year. Basically, these recommendations require increased
suppression (netting) of LT, while developing scientific approaches
to population estimates of both species, movement patterns of LT,
LT spawning site identification by a robust telemetry study,
experimentation with alternative technology to target LT eggs, and
periodic review by the scientific community.
Major strides have been made in the past few years by the NPS in
their approach.  Yellowstone Park administration changed over the
winter with Daniel Wenk being named Superintendent.  A
comprehensive fisheries management EA was published which
sets benchmarks for LT removal and YCT recovery.

The NPS netting effort was significantly increased by the hiring
of a commercial fishing crew from Wisconsin.  The NPS has
with NGOs (Trout Unlimited, Greater Yellowstone Coalition,
National Parks Conservation Association) to tackle the problem,
including the acceptance of financial support and input.  The
USGS began a major research effort in 2008 to identify
alternative suppression technology – targeting recruitment.  
Some of that technology is now ready to scale-up.  Electro-
shocking of LT eggs was used this past fall for the first time on
Lake Pend Oreille.  Results of that study are due this winter.  
The most significant advancement has been the start of a three
year hydro-acoustic telemetry study as a joint effort of all parties
to identify lake trout movement patterns and spawning beds.
Future Direction:
The key to YCT recovery is major suppression of LT (they will probably
never be eliminated) while at the same time, cutting off recruitment into
the LT population.  Central to this goal, is to know the location of their
spawning beds and movement patterns, thus a hydro-acoustic study
was initiated on August 16, 2011.  A total of 141 hydro-acoustic tags
were surgically implanted into lake trout.
Yellowstone Lake Receiver

Click map to enlarge.
Implanting hydro-acoustic tag
into lake trout "Judas Fish".
Movements of these fish are being monitored by 40 receivers
strategically located around the lake. Data  will be analyzed this
winter and reported in February at a meeting of the Yellowstone
Lake working group. This 3 year telemetry effort requires a
significant NPS, USGS and NGO commitment of money, research
time, and support.
Trout Unlimited, the National Park Service, the US Fish & Wildlife
Service, and the US Geological Survey are partnering to fund
research by Montana State University/USGS/USFWS to investigate
and develop alternative methods to reduce or eliminate the Lake
Trout in Yellowstone Lake.
Sponsor a "Judas Fish" and track it on line...
Donate a Lake Trout telemetry tag ($400) for Yellowstone Lake
100% of your tax deductible contribution goes to the
Make Checks payable to "Save the Yellowstone
Send to:  Trout Unlimited, P.O. Box 3008, Cody, WY  
For more information please call Dave Sweet, campaign
coordinator, (307)527-9959.
Watch telemetry traces on USGS
web site.
New UW Research Shows Grizzly Diet Shift Hits Elk Herds
May 15, 2013 — A decline in native Yellowstone cutthroat trout due in part to the
introduction of nonnative lake trout has driven a shift in the diets of grizzly bears
that helps explain losses in some migratory elk herds in the greater Yellowstone
area, according to new research published today
.  read more

Fewer Trout means less food for YNP  Raptors
May 13, 2013 - In an ecological chain reaction, an overabundance of non-native
mackinaw in Yellowstone Lake is hurting the cutthroat trout population, which in
turn makes slim pickings for osprey.  
read more
Yellowstone Lake Update for “The Trout Tale”
Winter 2013-2014

When the East Yellowstone Chapter in Cody entered into the fight in the fall of 2007 to “Save the Yellowstone Cutthroat” of
Yellowstone Lake, they had no idea how big the project would get or how long it would take to start seeing a recovery.
After all, this is a simple problem. All you have to do to recover the cutthroats is to get rid of the lake trout that were
somehow introduced into the system. Seems like a pretty simple solution. The strategy also didn't seem too tough – just
net out the majority of the adults and keep the rest from successfully spawning. But, 6 years later we are much wiser than
we were back then.

The road has been long, sometimes difficult, sometimes frustrating, but always rewarding. The greatest rewards have
been seeing the incredible support that fellow TU members, anglers, sportsmen and women, conservationists, and
agency folks have demonstrated for this iconic ecosystem. With only a few exceptions, the vast majority of people that we
have met refuse to accept as inevitable, the loss of this population. They have been willing to argue for its survival and to
put their energy and their resources into the effort. more
Update - Electroshocking to induce mortality of lake trout embryos on Carrington Island,
Yellowstone Lake
Since lake trout were first discovered in Yellowstone Lake in 1994, gillnetting has been the primary tool used to
suppress the population and conserve the native Yellowstone cutthroat trout. In recent years, large live entrapment
nets, set by contract netting crews, have also been used to target the large lake trout. Although it appears the
netting efforts applied in 2012 and 2013 have curtailed lake trout population growth and the Yellowstone cutthroat
trout may be rebounding, these trends will only continue by maintaining high levels of lake trout suppression
through the coming years. In 2014, the lake trout netting alone, using four large boats and contract crews, will cost
nearly $2 million. These costs are expected to increase annually.
To reduce costs and ensure program viability into the foreseeable future..
.read more
Click image to
Yellowstone Is Saving Native Trout With Lessons Learned From
(Gasp!) The Commercial Fishing Industry
Read Forbes article
2012-13 Lake trout population estimates show decline
Lake Trout population declined by 15% during the 2012-13 season as reported by Pat Bigelow, fisheries
biologist, NPS.
SF 82 guaranteed continued funding of studies for the lake trout mitigation in Yellowstone Lake.  Over
$620,000 will be availble for Save the Yellowstone Cutthroat efforts through the Wyoming Wildlife and Natural
Resources Trust.