Presenter Information

Michael J. KrummelFollow

Presentation Type

Poster

Faculty Mentor’s Full Name

Andrew Whiteley

Faculty Mentor’s Department

Fisheries and Conservation Genomics

Abstract

A long-held belief regarding stream-resident salmonid populations is that fish are predominately sedentary, termed the restricted movement paradigm. The existing literature has addressed whether fish are mobile and undergo long-range movements, or are sedentary and remain in small (20-50 m) reaches of the stream, or a combination of both. The restricted movement paradigm suggests resident salmonid populations are sedentary, however, limited studies exist on the restricted movement paradigm with respect to small, isolated riverine salmonid populations. We tested the restricted movement paradigm in four isolated Westslope Cutthroat Trout (Oncorhynchus clarkii lewisi )populations on the east side of the continental divide in Montana in the summers of 2017 and 2018. We conducted a mark/recapture study using electrofishing and recorded the stream segment fish were captured, using a 40-m resolution per stream reach. We will calculate the mean and variability in fish movements to determine if these populations align with the restricted movement paradigm. Movement distributions will be compared for short-term (seasonal) versus long-term (annual) movement. Additionally, we will examine how individual fish length and fish density influences movement using generalized linear models. This study will give us a detailed understanding of the movement patterns of Westslope Cutthroat Trout in these isolated systems, something that has not been well-studied. Movement is a critical ecological and evolutionary process that can give us a better understanding of population dynamics. As our study streams are fragmented and fish are restricted to available habitat, limited movement within the isolated habitat could suggest further implications to the persistence of these valuable populations.

Category

Life Sciences

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Apr 17th, 3:00 PM Apr 17th, 4:00 PM

Movement patterns of Westslope Cutthroat Trout populations in isolated headwater streams of Montana

UC South Ballroom

A long-held belief regarding stream-resident salmonid populations is that fish are predominately sedentary, termed the restricted movement paradigm. The existing literature has addressed whether fish are mobile and undergo long-range movements, or are sedentary and remain in small (20-50 m) reaches of the stream, or a combination of both. The restricted movement paradigm suggests resident salmonid populations are sedentary, however, limited studies exist on the restricted movement paradigm with respect to small, isolated riverine salmonid populations. We tested the restricted movement paradigm in four isolated Westslope Cutthroat Trout (Oncorhynchus clarkii lewisi )populations on the east side of the continental divide in Montana in the summers of 2017 and 2018. We conducted a mark/recapture study using electrofishing and recorded the stream segment fish were captured, using a 40-m resolution per stream reach. We will calculate the mean and variability in fish movements to determine if these populations align with the restricted movement paradigm. Movement distributions will be compared for short-term (seasonal) versus long-term (annual) movement. Additionally, we will examine how individual fish length and fish density influences movement using generalized linear models. This study will give us a detailed understanding of the movement patterns of Westslope Cutthroat Trout in these isolated systems, something that has not been well-studied. Movement is a critical ecological and evolutionary process that can give us a better understanding of population dynamics. As our study streams are fragmented and fish are restricted to available habitat, limited movement within the isolated habitat could suggest further implications to the persistence of these valuable populations.