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Silas Ratten

Silas Ratten


  • University of Maine 2013


Prior to my current project I was involved in fish research as a summer technician for Utah State University were I aided in a study focused on interactions between stream dwelling nonnative brook trout and Bonneville cutthroat trout. While in Utah, I also aided in research critical to understanding the movements and habitat preferences of endemic fishes in a tributary to the Green River, Utah.
As an undergraduate student and full time technician at the University of Maine I’ve been involved in a multitude of research projects including a studies focused on lake whitefish predation, the competitive interactions between juvenile Atlantic salmon and small mouth bass, annual arctic charr population assessments, investigations into small stream movements of native brook trout, understanding migrations of sea-run brook trout through otolith microchemistry, and evaluating the ability of sea lamprey to predispose Atlantic salmon spawning habitat.

Research Interests

My research project focuses on the growth, movements, and spawning behavior of lake whitefish in St. Froid and Clear Lakes, Maine. Historically lake whitefish were abundant and found throughout Maine’s lakes. In addition they provided a popular sport fishery for winter ice anglers. Currently, populations of these native fish have been reduced in abundance, now primarily residing in areas of northern Maine. Findings of the current research will provide critical information regarding the basic biology of lake whitefish in Maine and evaluate restoration efforts.
St. Froid Lake is located in Winterville, Maine and once inhabited a sustainable lake whitefish population but in the early 1900’s experienced extirpation. Currently management actions are being employed to restore lake whitefish in St. Froid Lake. These actions include an annual stocking of juvenile lake whitefish since 2003. Stocking classes are denoted by various fin clips implemented prior to release. In contrast to St. Froid Lake, Clear Lake located in T10 R11 WELS, Piscataquis County Maine hosts a robust, self-sustaining population of Lake whitefish. Clear Lake is the subject of an ongoing study since 2004 dedicated to understanding the seasonal movements of Lake whitefish. The continuation of this work will provide the only long term dataset of lake whitefish movements in Maine.
The objectives of this study are to (1) Characterize lake whitefish movements to better understand spawning locations, the time window when spawning occurs, and how summer movements relate to the lake stratification, (2) Assess lake whitefish growth (annual and seasonal) within Clear and St. Froid Lakes to evaluate current restoration efforts, and (3) Observe lake whitefish spawning and characterize size structure, timing, and duration of spawning events in Clear Lake.


Current Staff

Federal Staff: 3

Masters Students: 6

Phd Students: 7

Post Docs: 2

University Staff: 5

5 Year Summary

Students graduated: 26

Scientific Publications: 57

Presentations: 225


Contact Information

Tel: (207) 581 - 2921


Maine Cooperative Fish and Wildlife Research Unit Cooperators

  1. Maine Department of Inland Fisheries and Wildlife
  2. U.S. Fish and Wildlife Service
  3. U.S. Geological Survey
  4. University of Maine
  5. Wildlife Management Institute