|Progress and Results
The objectives of this project are to (a) develop methods that can be used to monitor and understand fish
movement in general, (b) document distribution and movement patterns of multiple sizes of blue catfish,
and (c) collect related data that will help explain reasons for distribution and movement of this important,
popular, and highly mobile sport fish.
Many Kansas anglers target this family of sport fish through specialized clubs (e.g., KC Catfish, Catfish
Chasers, US Catfish, US Catfish Association), largely because blue catfish provide trophy catches (i.e., KS
state record, 102.8 lbs). For example, in 2001, 216,000 Kansas anglers spent $40.1 million fishing for
catfish. Thus, the specific results from this research can provide technical guidance for stocking decisions,
better assessment protocols, basic scientific information on sport fish in general, and outreach to anglers.
Team Blue Catfish is a collaboration among biologists from KDWPT and KSU on a project administered through
the Kansas Cooperative Fish and Wildlife Research Unit (KCFWRU). In 2012, we developed and tested tagging
protocols at the KDWPT hatchery at Milford Lake. In 2012 and 2013, KDWPT biologists worked with KCFWRU
personnel to capture blue catfish for acoustic tagging and diet analysis. KCFWRU personnel are using these
tagging data to test hypotheses about patterns and drivers of blue catfish distribution. This research will
result in M.S. degrees in fisheries for Kayla Gerber and Zach Peterson through the Division of Biology at
Kansas State University.
Patterns of Distribution and Movement Blue Catfish (Kayla Gerber)
With KDWPT, on June 26-28, 2012, we surgically implanted 48 blue catfish (400-600 mm TL), captured at three
different locations in Milford Lake, with VEMCO V9 acoustic tags. Twenty VEMCO receivers, placed throughout
Milford Lake, 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 left Milford Lake. On June
3-6, 2013, an additional 75 blue catfish (mean = 517 mm TL, range = 361-1090 mm TL) were tagged with V9 and
V13 tags. Data were retrieved regularly and analyzed by monthly time periods.
In both years, all blue catfish survived the tagging. Tagged fish were detected over a million times each year.
No tagged catfish left Milford Lake 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. 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, and night even though
catfish are often assumed to change their distribution at night. Distribution changed across seasons with a
subset of tagged fish moving to the deeper lower part of Milford Lake 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 distribution and movement 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.
Drivers of Blue Catfish Distributional Patterns and Movements (Zachary Peterson)
A major goal in ecology and fisheries biology is to understand and predict spatial and temporal patterns of
organisms, the causes and consequences of those patterns, and the role of heterogeneity in space and time.
Consequently, research that helps to understand and predict the distribution and movements of mobile
organisms under current and changing conditions is of paramount scientific and management importance. This
research will focus on a highly mobile fish, the blue catfish, in a large, heterogeneous environment, Milford
reservoir, KS, to better understand and predict blue catfish distribution and movement.
This aspect of the project will address three objectives to explain which variables (e.g., depth, flow velocity,
geographic region, habitat type, prey, temperature, water quality) explain blue catfish distribution and
abundance. Specifically, for this project, we will identify ecologically important variables from the
peer-reviewed literature (Objective 1), test combinations of variables that explain and predict blue
catfish distribution with multiple habitat selection models (e.g., classification and regression trees,
logistic regression, discrete choice, electivity) (Objective 2), and map relationships between
combinations of variables and fish distribution (Objective 3).
Relevant abiotic and biotic variables were collected monthly at the same 57 locations from June to
November, 2013. For example, in 2013, 13,560 depth measurements and pictures with a side scan sonar,
3,750 temperature and dissolved oxygen measurements with a YSI, 375 secchi depths, 375 ponar grabs,
180 temperature logger downloads, and 150 acoustic doppler current profiles to measure water velocity
were recorded. Electrofishing resulted in capture and measurement of 2,150 fish prey. These spatially
and temporally explicit abiotic and biotic data were statistically and spatially related to blue catfish
location data via 285 manual tracking events at each of the 57 monthly survey locations. Spatial and
statistical analyses are underway.
Products since 2012:
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.
Kayla Gerber, 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