volume 14 • number 2 • spring 2006 Yellowstone Cutthroat Trout Conservation Source and Date of Lake Trout Introduction History of Lake Fish Hatchery NPS/MIKE YOCHIM Southeast arm of Yellowstone Lake. Manipulated Ecosystems y fi rst job in Yellowstone was as a Youth Conserva- resulting in a few reported catches. Regardless, studies such as tion Corps crew leader in the summer of 1993. For Munro et al.’s indicate that the current lake trout crisis is the Mthe last job of the season, our crew got to spend 10 result of recent, successful introductions. days camping at Trail Creek, near the southeast arm of Yellow- Yellowstone’s fi sheries have been tinkered with since at stone Lake. It was breathtaking to be on the lake in August. We least 1881, the date of the earliest fi sh stocking in the park. Tom felt thoroughly spoiled to be allowed to pass those long days in Olliff, the new Chief of the Yellowstone Center for Resources, what appeared to be such a remote, pristine environment. considers Yellowstone’s aquatic systems to be the park’s “most The next summer, news of the discovery that lake trout had disturbed” environments—not pristine at all. Also in this issue, been illegally introduced to the lake traveled quickly through- Lee Whittlesey records the history of former fi shery operations out the park’s administrative offi ces in Mammoth Hot Springs. and the hatchery at Yellowstone Lake, which were part of park People were sad and angry, wondering who did it and how, and managers’ early efforts to “improve” the fi shery for the benefi t what would happen to the lake’s native Yellowstone cutthroat of sportfi shers. Although park management later moved away trout. In this issue of Yellowstone Science, Andrew Munro et al.’s from manipulation toward protection of native species, today’s article reports on how they identifi ed the source and date of the ease and expansion of world travel and trade has brought with lake trout introduction in Yellowstone Lake. People continue it the movement and proliferation of non-native species, and to point out that Hiram M. Chittenden’s 1903 history, The new concerns. Yellowstone National Park: Historical and Descriptive, 4th ed., Invasive non-native species are now acknowledged world- lists “10,000 yearling lake trout” as having been planted by wide to be a major threat to biodiversity; once introduced, the U.S. Fish Commission “in the Yellowstone River above the efforts to control or eliminate them can be time-consuming falls in 1890.” An exhaustive search by John Varley of offi cial and expensive. Prevention is the key. Yellowstone now spends records on translocations has found no indication that such roughly $400,000 annually just to suppress lake trout popula- a plant took place. But if it did, the introduction failed, as tion growth. In the meantime, the lake’s native Yellowstone did others—Atlantic salmon were also planted in the lake and cutthroat trout, which provide an important source of energy never seen again. According to writer and historian Paul Schul- to at least 42 species of birds and mammals and have recently lery, not a single lake trout appears in the offi cial records of gill- supported a $36 million annual sport fi shery, also suffer from netting and fi sh management work in the park between 1900 the effects of whirling disease and drought. In their article, and 1990. However, highly credible observers have reported Todd Koel et al. describe the efforts of the park’s aquatic sci- catching lake trout in Yellowstone Lake over the park’s history. ences program to conserve the park’s native Yellowstone cut- This may suggest early introductions of lake trout to the lake, throat trout in the face of these and other threats. NPS/JIM PEACO a quarterly devoted to natural and cultural resources volume 14 • number 2 • spring 2006 TAMI BLACKFORD Editor ALICE WONDRAK BIEL Associate Editor VIRGINIA WARNER Photo Editor and Graphic Designer MARY ANN FRANKE Assistant Editor Aerial view of the Yellowstone River delta. ARTCRAFT PRINTERS, INC. Bozeman, Montana Printer FEATURES 4 Where Did They Come From? Natural Chemical Markers Identify Source and Date of Lake Trout Yellowstone Science is published quarterly. Introduction in Yellowstone Lake Support for Yellowstone Science is provided by the Yellowstone Association, a non-profi t educational organization dedicated to serving Andrew R. Munro, Thomas E. McMahon, and James R. Ruzycki the park and its visitors. For more information about the association, including membership, or to donate to the production of Yellowstone 13 Of Fairies’ Wings and Fish Science, visit www.yellowstoneassociation.org or write: Yellowstone Association, P.O. Box 117, Fishery Operations and the Lake Fish Hatchery in Yellowstone Yellowstone National Park, WY 82190. The opinions expressed in Yellowstone Science are the authors’ and may not refl ect either Lee H. Whittlesey National Park Service policy or the views of the Yellowstone Center for Resources. Copyright © 2006, the Yellowstone Association 20 Conserving Yellowstone Cutthroat Trout for Natural Science, History & Education. Yellowstone’s Aquatic Sciences Program For back issues of Yellowstone Science, please see www.nps.gov/yell/publications. Todd M. Koel, Patricia E. Bigelow, Philip D. Doepke, Submissions are welcome from all investigators Brian D. Ertel, and Daniel L. Mahony conducting formal research in the Yellowstone area. To submit proposals for articles, to subscribe, or to send a letter to the editor, please write to the following address: Editor, Yellowstone Science, P.O. Box 168, Yellowstone National Park, WY 82190. You may also email: [email protected]. DEPARTMENTS Yellowstone Science is printed on recycled paper 2 News & Notes with a soy-based ink. Winter Elk Count • Late Winter Bison Population Estimate • Frederick Turner’s Passing on the cover From the Archives Yellowstone cutthroat trout, 29 courtesy Mimi Matsuda. NEWS & NOTES NPS/BECKY WYMAN 2006 Winter Elk Count recruitment year to move back into an interagency approach to answering a Standard Hunting Season package. questions and solving problems. The Northern Yellowstone Coop- However, this year’s data on recruit- erative Wildlife Working Group ment, harvest, migration size, and win- Yellowstone Late Winter conducted its annual, late winter clas- ter distribution may allow for a modest Bison Population Estimate sifi cation of northern Yellowstone elk increase in antlerless permits within on March 23, 2006. Biologists traveled the existing Restrictive Season frame- The recently completed 2006 late by helicopter to classify a total of 3,649 work for the January 2007 Gardiner winter bison population estimate is elk as bulls, cows, or calves in specifi ed late hunt.” Final elk permit quotas will 3,500 bison. sampling areas throughout the north- be set by the Fish, Wildlife and Parks Based on a late winter aerial survey, ern winter range during the one-day Commission in July 2006. the estimate takes into account the survey. Northern Yellowstone elk win- Due to a lack of snow cover and 2005 late summer population estimate ter between the northeast entrance of unusually windy conditions, the work- of 4,900 bison, known brucellosis risk Yellowstone National Park and Dome ing group was unable to complete the management mortalities, and scientifi c Mountain/Dailey Lake in the Paradise annual winter trend count of northern estimates of over-winter mortality rates. Valley. Yellowstone elk during the typical The population estimate is used to Estimated sex and age ratios for the period in late December or early Janu- guide adaptive management strategies population were 24 calves and 20 bulls ary. Biologists attempted to conduct under the Interagency Bison Manage- per 100 cows. Calf ratios averaged 20 a count on March 22, 2006, but elk ment Plan (IBMP). Specifi c manage- calves per 100 cows inside the park inside the park were widely distributed ment actions may be modifi ed based and 27 calves per 100 cows north of at higher elevations and in timbered on expected late winter population lev- the park boundary. The overall ratio of areas, which made detection diffi cult els as corroborated by the annual late 24 calves per 100 cows is higher than and unreliable compared to previous winter estimate. the late-winter ratios of 12–14 calves winters. Thus, the count was consid- During winter, 939 bison were per 100 cows during 2002–2005, and ered poor and inaccurate, and results removed from the wild bison popula- within the range of 22–34 calves per are not comparable to surveys during tion through capture operations at 100 cows observed during the previous good conditions in previous years. Stephens Creek, in accordance with six years. The working group, comprised the IBMP. This is the sixth winter the P.J. White, biologist for Yellow- of resource managers and biologists IBMP has been used to guide brucel- stone National Park, indicated, “The from the Montana Department of losis risk management actions. increase in recruitment this year prob- Fish, Wildlife and Parks; Yellowstone The IBMP is a cooperative plan ably refl ects less predation by wolves National Park; Gallatin National designed to protect Montana’s brucel- and, in part, a decrease in antlerless elk Forest; and U.S. Geological Survey– losis-free status while allowing for the harvest.” An apparent disease outbreak Northern Rocky Mountain Science conservation of a viable, wild bison reduced wolf numbers on the northern Center, will continue to monitor trends population. Protecting Montana’s range by 40% during summer 2005. of the elk population and evaluate the brucellosis-free status requires keeping Also, Montana Fish, Wildlife and Parks relative contribution of various compo- bison from mixing with cattle grazing signifi cantly reduced antlerless elk per- nents of mortality, including predation, on land outside the park.