Characteristics of a New Rainbow Trout Population: Spirit Lake, Mount St. Helens Volcano, 2000–2015

  • Tara E. Blackman
  • Charles M. Crisafulli
  • Shannon M. Claeson


Spirit Lake was grossly altered by the 1980 eruption of Mount St. Helens and all air-breathing life perished. A rainbow trout (Oncorhynchus mykiss) population was established circa 1991 and monitored from 2000 to 2014. During that time, the trout population increased, and individual fish size significantly decreased (both length and mass). Fish diets were primarily composed of small prey items, mostly aquatic insects and aquatic snails, and piscivory was not observed. The relatively recent (2011) observation of juvenile fish occupying streams draining into Spirit Lake suggests an increased suitability of stream habitat for both spawning and rearing, which may account for the changing population dynamics and annual variation.


Mount St. Helens Rainbow trout Volcanic disturbance Life history Fish diet Population dynamics Adfluvial Disturbance gradient Salmonid ecology Stream habitat 



This work was supported by funding from the USDA Forest Service, Pacific Northwest Research Station, and the National Science Foundation (LTREB Program, DEB-0614538) to CMC. Our project benefitted from early collaborations and discussions with Bob Lucas, John Weinheimer, and Chris Wageman of the Washington Department of Fish and Wildlife. Juvenile fish aging was made possible through the support of Gordon Reeves’s lab. We thank the numerous field and lab assistants whose help made this project possible. We thank Kathryn Ronnenberg and Kelly Christiansen for producing final figures and tables.


Volcanic Processes

Blast pyroclastic density current (blast PDC)

In the case of the 1980 Mount St. Helens eruption, failure of the volcano’s north flank unroofed pressurized magma and superheated water. Rapid exsolution of magmatic gases and conversion of superheated water to steam produced a laterally directed blast, which formed a density current that flowed across rugged topography. The current contained fragmented rock debris as well as shattered forest material.


An Indonesian term for a rapid granular flow of a fully saturated mixture of volcanic rock particles (± ice), water, and commonly woody debris. A lahar that has ≥50% solids by volume is termed a debris flow; one that has roughly 10–50% solids by volume is termed a hyperconcentrated flow. Flow type can evolve with time and distance along a flow path as sediment is entrained or deposited.

Pyroclastic flow

Rapid flow of a dry mixture of hot (commonly >700 °C) solid particles, gases, and air that has a ground-hugging flow that is often directed by topography. Flows are generally gravity driven but may be accelerated initially by impulsive lateral forces of directed volcanic explosions. Flows typically move at high velocity (up to several hundred km hr−1).


A rain of volcanic particles to the ground following ejection into the atmosphere by an explosive eruption. Tephra is a collective term for particles of any size, shape, or composition ejected in an explosive eruption.

Other Terms

Adfluvial (adj)

Describes life-history strategy in which adult fish spawn and juveniles subsequently rear in streams but migrate to lakes for feeding as subadults and adults.

Anadromous (adj)

Describes fish that ascend rivers or streams to spawn. Subdivision of diadromous.

Mesotrophic (adj)

Describes a body of water having a moderate amount of dissolved nutrients as compared to high levels (eutrophic) or low levels (oligotrophic).

Refugia (n, pl)

Locations that support isolated populations of a once more widespread species. Isolation at Mount St. Helens was caused by intense and high severity disturbance from volcanic forces during the eruption that reduced or eliminated organisms from areas surrounding the refugia.

Thalweg (n)

The trajectory of the connection of lowest points of the channel bed along the length of a stream channel. The thalweg marks the natural direction of a watercourse.

Ultra-oligotrophic (adj)

Having low primary productivity; pertaining to waters having low levels of the mineral nutrients required by green plants. Used of a lake which the hypolimnion does not become depleted of oxygen during the summer.


  1. Bisson, P.A., R.E. Bilby, M.D. Bryant, C.A. Dolloff, G.B. Grette, R.A. House, M.L. Murphy, K.V. Koski, and J.R. Sedell. 1987. Large woody debris in forested streams in the Pacific Northwest: Past, present, and future. In Streamside management: Forestry and fishery interactions, Proceedings of the symposium Contribution No. 57, ed. E.O. Salo and T.W. Cundy, 143–190. Seattle: College of Forest Resources, University of Washington.Google Scholar
  2. Bisson, P.A., J.L. Nielsen, and J.W. Ward. 1988. Summer production of coho salmon stocked in Mount St. Helens streams 3–6 years after the 1980 eruption. Transactions of the American Fisheries Society 117: 322–335.CrossRefGoogle Scholar
  3. Bisson, P.A., C.M. Crisafulli, B.R. Fransen, R.E. Lucas, and C.P. Hawkins. 2005. Responses of fish to the 1980 eruption of Mount St. Helens. In Ecological responses to the 1980 eruption of Mount St. Helens, ed. V.H. Dale, F.J. Swanson, and C.M. Crisafulli, 163–181. New York: Springer.CrossRefGoogle Scholar
  4. Blackman, T.E. 2014. Life-history strategies of rainbow trout (Oncorhynchus mykiss) cross a volcanic disturbance gradient at Mount St. Helens, Washington. Masters thesis. Corvallis: Oregon State University.Google Scholar
  5. Bortleson, G.C., N.P. Dion, J.B. McConnell, and L.M. Nelson. 1976. Reconnaissance data on lakes in Washington. Volume 2, King and Snohomish Counties. State of Washington, Department of Ecology Water-Supply Bulletin No. 43.Google Scholar
  6. Campana, S.E., and J.D. Neilson. 1985. Microstructure of fish otoliths. Canadian Journal of Fisheries and Aquatic Sciences 42: 1014–1032.CrossRefGoogle Scholar
  7. Crawford, B.A. 1986. Recovery of game fish populations impacted by the May 18, 1980 eruption of Mount St. Helens. Part II. Recovery of surviving fish populations within the lakes in the Mount St. Helens National Volcanic Monument and Adjacent Areas. Fishery Management Report 85-9B. Vancouver: Washington Department of Fish and Game.Google Scholar
  8. Crisafulli, C.M., and C.P. Hawkins. 1998. Ecosystem recovery following a catastrophic disturbance: Lessons learned from Mount St. Helens. In Status and trends of the nation’s biological resources, Vol. 2. ed. M.J. Mac, P.A. Opler, C.E. Puckett Haecker, and P.D. Doran, 253–310. Reston: U.S. Geological Survey. Scholar
  9. Dahm, C.N., D.W. Larson, R.R. Petersen, and R.C. Wissmar. 2005. Response and recovery of lakes. In Ecological responses to the 1980 Eruption of Mount St. Helens, ed. V.H. Dale, F.J. Swanson, and C.M. Crisafulli, 255–274. New York: Springer.CrossRefGoogle Scholar
  10. Daubenmire, R. 1959. A canopy-coverage method of vegetational analysis. Northwest Science 33: 43–64.Google Scholar
  11. Foxworthy, B.L., and M. Hill. 1982. Volcanic eruptions of 1980 at Mount St. Helens: The first 100 days, Professional Paper 1249. Washington, DC: U.S. Geological Survey.Google Scholar
  12. Hawkins, C.P., and J.R. Sedell. 1990. The role of refugia in the recolonization of streams devastated by the 1980 eruption of Mount St. Helens. Northwest Science 64: 271–274.Google Scholar
  13. Hawkins, C.P., J.L. Kershner, P.A. Bisson, M.D. Bryant, L.M. Decker, S.V. Gregory, D.A. McCullough, C.K. Overton, G.H. Reeves, R.J. Steedman, and M.K. Young. 1993. A hierarchical approach to classifying stream habitat features. Fisheries 18 (6): 3–12.CrossRefGoogle Scholar
  14. Larson, D.W. 1993. The recovery of Spirit Lake. American Scientist 81: 166–177.Google Scholar
  15. Larson, D.W., J.W. Sweet, R.R. Peterson, and C.M. Crisafulli. 2006. Posteruption response of phytoplankton and zooplankton communities in Spirit Lake, Mount St. Helens, Washington. Lake and Reservoir Management 22: 273–292.CrossRefGoogle Scholar
  16. Leider, S.A. 1989. Increased straying by adult steelhead trout, Salmo gairdneri, following the 1980 eruption of Mount St. Helens. Environmental Biology of Fishes 24: 219–229.CrossRefGoogle Scholar
  17. Lucas, R.E., and B.A. Crawford. 1986. Recovery of game fish populations impacted by the May 18, 1980, eruption of Mount St. Helens. Part I. Recovery of winter-run steelhead in the Toutle River watershed. Fishery Management Report 85-9A. Olympia: Washington Department of Game, Fisheries Management Division.Google Scholar
  18. Lucas, R.E., and K. Pointer. 1987. Wild steelhead spawning escapement estimates for Southwest Washington streams—1987, Fishery Management Report. 87–6. Olympia: Washington Department of Wildlife, Fisheries Management Division.Google Scholar
  19. Lucas, R.E., and J. Weinheimer. 2003. Recovery of fish populations affected by the May 18th, 1980 eruption of Mount St. Helens. Olympia: Washington Department of Fish and Wildlife.
  20. Major, J.J., T.C. Pierson, R.L. Dinehart, and J.E. Costa. 2000. Sediment yield following severe volcanic disturbance—A two-decade perspective from Mount St. Helens. Geology 28: 819–822.<819:SYFSVD>2.0.CO;2.CrossRefGoogle Scholar
  21. Martin, D.J., L.J. Wasserman, R.P. Jones, and E.O. Salo. 1982. Effects of the eruption of Mount St. Helens on salmon populations and habitat of the Toutle River. In Proceedings from the conference, Mount St. Helens: Effects on water resources, Report No. 41, 235–254. Pullman: State of Washington Water Research Center, Washington State University.Google Scholar
  22. Martin, D.J., L.J. Wasserman, and V.H. Dale. 1986. Influence of riparian vegetation on posteruption survival of coho salmon fingerlings on the west-side streams of Mount St. Helens, Washington. North American Journal of Fisheries Management 6: 1–8.CrossRefGoogle Scholar
  23. McPhail, J.D., and C.C. Lindsey. 1986. Zoogeography of the freshwater fishes of Cascadia (the Columbia system and rivers north to the Stikine). In Zoogeography of North American freshwater fishes, ed. C.H. Hocutt and E.O. Wiley, 615–637. New York: Wiley.Google Scholar
  24. Milner, A.M., E.E. Knudsen, C. Soiseth, A.L. Robertson, D. Schell, I.T. Phillips, and K. Magnusson. 2000. Colonization and development of stream communities across a 200-year gradient in Glacier Bay National Park, Alaska, U.S.A. Canadian Journal of Fisheries and Aquatic Sciences 57: 2319–2335. Scholar
  25. Milner, A.M., A.L. Robertson, K.A. Monaghan, A.J. Veal, and E.A. Flory. 2008. Colonization and development of an Alaskan stream community over 28 years. Frontiers in Ecology and the Environment 6: 413–419.CrossRefGoogle Scholar
  26. Ogle, D.H. 2013. FSA: Fisheries stock analysis. R package version 0.4.3.
  27. Olds, C. 2002. Fisheries studies at the sediment retention structure on the North Fork Toutle River 1993, 2001, and 2002. Prepared for the U.S. Army Corps of Engineers, Portland District, Contract 36001648. Olympia: Washington Department of Fish and Wildlife.Google Scholar
  28. Pavlov, D.S., K.A. Savvaitova, K.V. Kuzishchin, M.A. Gruzdeva, A.Yu. Mal’tsev, and J.A. Stanford. 2008. Diversity of life strategies and population structure of Kamchatka mykiss Parasalmo mykiss in the ecosystems of small salmon rivers of various types. Journal of Ichthyology 48: 37–44.CrossRefGoogle Scholar
  29. Quinn, T.P. 2005. The behavior and ecology of Pacific salmon and trout. American Fisheries Society, Bethesda, and University of Washington Press, Seattle.Google Scholar
  30. Redding, J.M., and C.B. Schreck. 1982. Mount St. Helens ash causes sublethal stress responses in steelhead trout. In Proceedings from the conference, Mount St. Helens: Effects on water resources, Report No. 41, 300–307. Pullman: State of Washington Water Research Center, Washington State University.Google Scholar
  31. Roni, P., and T.P. Quinn. 2001. Density and size of juvenile salmonids in response to placement of large woody debris in western Oregon and Washington streams. Canadian Journal of Fisheries and Aquatic Sciences 58: 282–292.CrossRefGoogle Scholar
  32. Stober, Q.J., B.D. Ross, C.L. Melby, P.A. Dinnel, T.H. Jagielo, and E.O. Salo. 1981. Effects of suspended volcanic sediment on coho and Chinook salmon in the Toutle and Cowlitz rivers. Technical Completion Report, Contract No. 14-34-0001-1417. Washington Department of Fisheries; Office of Water Research and Technology, U.S. Department of the Interior; State of Washington Water Research Center.
  33. Swanson, F.J., and J.J. Major. 2005. Physical events, environments, and geological–ecological interactions at Mount St. Helens: March 1980–2004. In Ecological responses to the 1980 eruption of Mount St. Helens, ed. V.H. Dale, F.J. Swanson, and C.M. Crisafulli, 27–44. New York: Springer.CrossRefGoogle Scholar
  34. Swanson, F.J., C.M. Crisafulli, and D.K. Yamaguchi. 2005. Geological and ecological settings of Mount St. Helens before May 18, 1980. In Ecological responses to the 1980 eruption of Mount St. Helens, ed. V.H. Dale, F.J. Swanson, and C.M. Crisafulli, 13–26. New York: Springer.CrossRefGoogle Scholar
  35. Wissmar, R.C., A.H. Devol, A.E. Nevissi, and J.R. Sedell. 1982. Chemical changes of lakes within the Mount St. Helens blast zone. Science 216: 175–178. Scholar
  36. Wydoski, R.S., and R.R. Whitney. 2003. Inland fishes of Washington. Bethesda/Seattle: American Fisheries Society/University of Washington Press.Google Scholar

Copyright information

© Springer Science+Business Media LLC 2018

Authors and Affiliations

  • Tara E. Blackman
    • 1
  • Charles M. Crisafulli
    • 1
  • Shannon M. Claeson
    • 2
  1. 1.U.S. Department of Agriculture, Forest Service, Pacific Northwest Research StationMount St. Helens National Volcanic MonumentAmboyUSA
  2. 2.U.S. Department of Agriculture, Forest Service, Pacific Northwest Research StationWenatchee Forestry Sciences LaboratoryWenatcheeUSA

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