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Assessing Distribution and Movement of Blue Catfish in Kansas Reservoirs

Kayla Gerber, M.S. Student
Zach Peterson, M.S. Student
Dr. Martha Mather

Professional Colleagues:
Dr. Joseph Smith, Post-doctoral Fellow

Project Supervisor
Dr. Martha Mather
Kansas Department of Wildlife, Parks, and Tourism
Milford Reservoir
August 2015

Kansas Department of Wildlife, Parks, and Tourism
Kansas State University

Determine distribution and seasonal movements of the blue catfish in a large reservoir.
Assess correlates of this distribution.
Progress and Results
The objectives of this project were to (a) develop methods that can be used to monitor and understand sport fish movement, (b) document distribution and egress patterns of multiple sizes of Blue Catfish in Milford Reservoir, KS, and (c) collect related data that will help explain reasons for distribution and egress of this important, popular, and highly mobile sport fish. Many Kansas anglers target catfish through specialized clubs (e.g., KC Catfish, Catfish Chasers, US Cats, and U.S. Catfish Association). For example, in 2001, 216,000 Kansas anglers spent $40.1 million fishing for catfish. Blue Catfish, in particular, provide trophy catches (i.e., KS state record, 102.8 lbs). Thus, the results from this research can provide basic scientific, management, and outreach information.

In 2012, Team Blue Catfish developed and tested tagging protocols at the KDWPT hatchery at Milford Reservoir. On June 26-28, 2012, Team Blue Catfish surgically implanted 48 Blue Catfish captured at three different locations in Milford Reservoir with VEMCO V9 acoustic tags. In 2012, mean size of Blue Catfish was 487 mm total length (TL) (range = 383-1020 mm TL; SE = 14.5; 88% of tagged fish were 400-600 mm TL, the most common sized fish in Milford Reservoir). Twenty VEMCO receivers, placed throughout Milford Reservoir, recorded the date, time, and location of fish distribution when tagged fish moved within 300 m of the stationary receivers. Two of these receivers detected if any tagged fish egressed Milford Reservoir either through the upstream Republican River or downstream over the dam. On June 3-6, 2013, an additional 75 Blue Catfish were tagged with V9 and V13 acoustic tags. In 2013, we tagged smaller and larger Blue Catfish as they became available, resulting in an average size of 517 mm TL (range = 343-1090 mm TL; SE = 17.8; 71% of the tagged fish were 400-600 mm TL). Data were retrieved regularly.

In both years, all Blue Catfish survived the tagging and were detected over a million times each year. No tagged catfish left Milford Reservoir through the upper or lower connections to the Republican River. In the field, 85.4-100.0% of the tagged catfish were detected at least once a month from June-November in both years. All tagged Blue Catfish moved throughout the reservoir and were detected at an average of 6-10 receivers. No differences in tagged Blue Catfish distribution were observed across dawn, day, dusk, night. Distribution changed across seasons with a subset of tagged fish moving to the deeper lower part of Milford Reservoir in the fall. Individual fish did not behave the same. Specifically, based on the results of a cluster analysis that used the amount of time tagged fish spent at each receiver, groups of fish differed in their space use and movement patterns. These multiple clusters illustrate different types of behavior within a single population. Although all tagged fish moved on a regular basis, the majority of fish spent most of their time in the middle portion of the reservoir.

This research resulted in M.S. degrees for Kayla Gerber and Zachary Peterson through the Division of Biology at Kansas State University (May, 2015). Their theses are described below.


Kayla Gerber Thesis. Tracking Blue Catfish: Quantifying System Wide Distribution of a Mobile Fish Predator Throughout a Large Heterogeneous Reservoir.
A flexible distribution is an adaptive response that allows animals to take advantage of spatial variation in the fluctuation of resources. Distribution of mobile organisms is complex so multi-metric patterns derived from dynamic distribution trajectories must be deconstructed into simpler components for both individuals and populations. Tagging and tracking fish is a very useful approach for addressing these fisheries research questions, but methodological challenges impede its effectiveness as a research tool. This research project developed and evaluated a high-retention, high-survival tagging methodology for catfish. Then, Team Blue Catfish integrated multiple distribution metrics to identify if sites within an ecosystem function differently for mobile predators. Finally, Kayla and colleagues determined if distinct groups of individuals existed, based on distributional patterns. The research team also tested sources of variation in system-wide detections (i.e., season, diel period, size, and release location) and provided additional details on methods and interpretation of the results. To address these objectives, the study tracked 123 acoustically tagged (VEMCO V9-V13) Blue Catfish (Ictalurus furcatus mean: 505.3 mm TL; SE: 12.3 mm; range: 300-1090 mm) from June through November, 2012-2013, in Milford Reservoir, KS. Across the five months, 85.4-100.0% of the tagged Blue Catfish were detected at least once a month by an array of 20 stationary receivers (VR2W), a detection rate much higher than rates reported in the literature for catfish (38%). Blue Catfish were consistently aggregated in the northern portion of the middle region of Milford Reservoir. Using three metrics (population proportion, residence time, and movements), this study found four types of functional sites that included locations with (i) large, active aggregations, (ii) exploratory/transitory functions, (iii) small, sedentary aggregations, and (iv) low use. This study also found that tagged Blue Catfish clustered into three groups of individuals based on distribution. These included (1) seasonal movers, (2) consistent aggregations across seasons, and (3) fish exhibiting site fidelity to Madison Creek. Sites with different functions and groups of individual fish were related but not the same. The approach to looking at multiple responses, functions of sites, and individual groupings provided new insights into fish ecology that can advance fisheries management of mobile predators.


Zachary Peterson Thesis. uantifying Patterns and Select Correlates of the Spatially and Temporally Explicit Distribution of a Fish Predator (Blue Catfish, Ictalurus Furcatus) Throughout a Large Reservoir Ecosystem.
Understanding how and why fish distribution is related to specific habitat characteristics underlies many ecological patterns and is crucial for effective research and management. Blue Catfish, Ictalurus furcatus, are an important concern for many fisheries agencies. However, lack of information about their distribution and habitat use remains a hindrance to proper management. Here, over all time periods and across months, Team Blue Catfish quantified fish distribution and environmental correlates of distribution in Milford Reservoir, the largest reservoir in Kansas. This research tested relationships among acoustically tagged Blue Catfish and three groups of variables postulated to influence Blue Catfish distribution in the literature (i. localized microhabitat variables, ii. larger-scale mesohabitat variables, iii. biotic variables). Blue Catfish were consistently aggregated in two locations of the reservoir across five months during summer and fall, 2013. Using multiple linear regression and an information theoretic model selection approach, consistent correlates of distribution included localized, microhabitat variables (i.e., dissolved oxygen, slope) larger-scale, mesohabitat variables (i.e., distance to channel, river kilometer from the dam) and a biotic variable (i.e., Secchi depth). This research identified which five of the 12 variables identified in the literature were most influential in determining Blue Catfish distribution. As a guide for future hypothesis generation and research, this study proposes that Blue Catfish distribution was driven by three ecologically-relevant tiers of influence. First, Blue Catfish avoided extremely low dissolved oxygen concentrations that could cause physiological stress. Second, Blue Catfish aggregated near the channel, an area of bathymetric heterogeneity that may offer a foraging advantage. Third, Blue Catfish aggregated near low Secchi depths, shown here to be associated with increased productivity. Building on these results, future research into the distribution and habitat use of Blue Catfish should incorporate aggregated distributions of fish into research designs, focus on how both small and large scale relationships interact to produce patterns of distribution, and explore further the mechanisms, consequences, and interactions among the three tiers of influence identified here.



Peer-reviewed Publications:

Gerber, K. M., M. E. Mather, and J. M. Smith. 2017. A suite of standard post-tagging evaluation metrics can help assess tag retention for field-based fish telemetry research. Reviews in Fisheries and Fish Biology DOI: 10.1007/s11160-017-9484-z


Gerber, Kayla (M.S., 2015; advisor Mather) Tracking blue catfish: quantifying system-wide distribution of a mobile fish predator throughout a large heterogeneous reservoir. M.S. Thesis, Kansas State University.

Peterson, Zachary (M.S., 2015; advisor Mather) Quantifying patterns and select correlates of the spatially and temporally explicit distribution of a fish predator (Blue Catfish, Ictalurus furcatus) throughout a large reservoir ecosystem. M.S. Thesis, Kansas State University.


Mather, M., K. Gerber, Z. Peterson. 2015. Assessing distribution and movement of blue catfish In Kansas reservoirs. Final Report to Kansas Wildlife, Parks, and Tourism.

Professional Presentations

Smith, J. M., M. E. Mather, and K. M. Gerber. 2016. Seasonal and diel patterns of depth and temperature distribution of Blue Catfish in Milford Reservoir, KS. Presentation was part of the symposium entitled "Blue Catfish: Lessons from a large riverine opportunistic catfish." 146th Annual Meeting of the American Fisheries Society. Kansas City, MO.

Gerber, K. M., M. E. Mather, J. M. Smith, and Z. Peterson. 2016. Identifying overall, seasonal, and diel patterns for reservoir-wide distribution of Blue Catfish: filling critical gaps for fish ecology and fisheries management. Presentation was part of the symposium entitled "Blue Catfish: Lessons from a large riverine opportunistic catfish." 146th Annual Meeting of the American Fisheries Society. Kansas City, MO.

Peterson, Z., M. E. Mather, J. M. Smith, and K. M. Gerber. 2016. Correlates of the whole-system distribution of a reservoir predator (Blue Catfish, Ictalurus Furcatus). Presentation was part of the symposium entitled "Blue Catfish: Lessons from a large riverine opportunistic catfish." 146th Annual Meeting of the American Fisheries Society. Kansas City, MO.

Gerber, K.M. and M.E. Mather. 2015. A high retention methodology for surgically implanting telemetry tags in catfish. 2015 Kansas Natural Resource Conference, Wichita, KS.

Gerber, K.M., M.E. Mather, J.M. Smith, and Z. Peterson. 2015. Distribution patterns of individual fish predators (Blue Catfish) in a Midwestern reservoir. 75th Midwest Fish and Wildlife Conference, Indianapolis, IN.

Gerber, K.M., M.E. Mather, J.M. Smith, and Z. Peterson. 2014. Patterns of variability in the distribution and movement of individual fish predators in a heterogeneous aquatic ecosystem. Presentation. 144th Annual AFS Conference, Quebec City, Quebec, Canada.

Peterson, Z.J., M.E. Mather, K.M. Gerber, and J.M. Smith. 2014. Evaluating the adequacy of fish-habitat data for the blue catfish. Upcoming Presentation. 144th Annual AFS Conference, Quebec City, Quebec, Canada.

Gerber,Kayla, Martha Mather, Joseph Smith and Zach Peterson. 2014. Distribution and movement of predators in a heterogeneous aquatic ecosystem. Graduate Student Research Forum, Division of Biology, Kansas State University.

Gerber, K. M., M. E. Mather, Z. Peterson, J. M. Smith, J. Reinke, J. Goeckler. 2012. Where are those $$#@@ fish?; Distribution and movement of a top predator (blue catfish) in a large, highly-variable Midwestern reservoir. Midwest American Fisheries Society Meeting, Wichita, KS.

Peterson, Z., K. Gerber., M. E. Mather, and J. Smith. 2012. Quantifying spatially-explicit patterns in a large reservoir: an approach for determining associations between a top fish predator and physical habitat. Midwest American Fisheries Society Meeting, Wichita, KS. Poster