Field Notes
U.S. Fish & Wildlife Service
Field Notes Entry   
Asian Carp in the Upper Mississippi River
Midwest Region, March 12, 2014
Print Friendly Version
VR2W (Acoustic receiver)
VR2W (Acoustic receiver) - Photo Credit: USFWS
Deploying VR2W on a navigation buoy
Deploying VR2W on a navigation buoy - Photo Credit: USFWS
V16 acoustic transmitter
V16 acoustic transmitter - Photo Credit: USFWS
Trevor and Mathew holding a bighead
Trevor and Mathew holding a bighead - Photo Credit: USFWS
Inserting transmitter during surgery
Inserting transmitter during surgery - Photo Credit: USFWS

Professionally speaking, the past year was sensational for me given the opportunity to lead a La Crosse Fish and Wildlife Conservation Office project to monitor Asian carp in the Upper Mississippi River (UMR). Our ongoing objectives are to assess the environmental history, movement, habitat selection, reproductive success and population dynamics (e.g., age structure, growth rates) of Asian carp in the UMR.

We began our work in May by assisting the Missouri Department of Conservation (MDC) and Iowa Department of Natural Resources (DNR) collect Asian carp in Pool 20 near Keokuk, Iowa. Some have asked, “Why Pool 20?” Well, Lock and Dam 19 currently serves as a major bottleneck (i.e., presumed passable only through the lock chamber) for fish passage on the UMR which has slowed the invasion of Asian carp upstream.

I was really excited for this trip because Pool 20 contains a high density of Asian carp, and we were surgically implanting acoustic transmitters into bighead and silver carp to monitor their movements. Sara Tripp, who works for the Missouri Department of Conservation (MDC) and has completed hundreds of these surgeries, was an outstanding mentor who taught me proper anesthesia and surgical techniques. The MDC now has fifteen bighead and ten silver carp with acoustic transmitters in Pool 20, which will be monitored to determine the proportion and rate at which they emigrate upstream. This trip provided us with new techniques and skills that were used the rest of the year.

During the 2013 sampling season, my crew implanted acoustic transmitters in a total of 27 Asian carp that ranged in size from 712 mm to 1170 mm (total length) and included twelve silver carp in Pool 17, five silver carp and five bighead carp in Pool 19, and five bighead carp in Pool 20. The movements of these fish were subsequently monitored using an array of acoustic receivers (VR2Ws) that were deployed at fixed sites over a 580 river-mile reach that extended from near Davenport (IA) downstream to Caruthersville (MO).Nearly 3,000 fish detections were logged in Pools 17 and 18.

Meanwhile, acoustic data analysis is continuing for sites located further downstream. Roving telemetry was also conducted by mounting acoustic receivers on commodity barges to detect fish as towboats pushed cargoes up and down the Mississippi River, allowing us to track fish without deploying a crew. Fish were also located manually to determine habitat and physiochemical usage. By year’s end, no fish were observed moving upstream, but 22 percent of the fish tagged and released in Pool 17 were observed moving downstream to Pool 18.

This year we plan to implant 123 more fish with transmitters to increase our sample size. We will also work further upstream with the Minnesota DNR to deploy additional receivers. This will expand the number of receivers in the array to 150, spanning 970 river miles, and include locations on several tributaries of the UMR that will extend as far as upstream as St. Croix Falls (WI) on the St. Croix River. The telemetry study will conclude by 2017 when transmitter battery-life is due to expire.

For the fish that didn’t receive transmitters, each fish was euthanized and an age estimation structure (Otolith) was removed. Otoliths (ear bones) were collected from 14 bighead and 67 silver carp captured in Pools 7, 17, and 19 during 2013 to address age structure, growth, mortality, and environmental history concerns. We also assisted the MDC collect otoliths from several hundred Asian carp in Pool 20. All otoliths will be sectioned, mounted, and examined independently to estimate the age of each fish. With the age information we will be able to estimate age structure, growth, and mortality and will use this information for future population models. Otolith samples will also be sent to Southern Illinois University (Carbondale, IL) and the University of Massachusetts (Boston, MN) for trace element and isotope analysis to assess environmental history. Data from these chemical analyses will be used to identify the river basin of origin (e.g., UMR, middle Mississippi River, and Illinois River) as well as the rivers (and perhaps the pools) occupied by each fish throughout its life. This information should indicate where adults have successfully spawned and where larval/juvenile fish disperse after hatching. Additional otoliths will be collected in 2014 to increase the sample size in pools above Lock and Dam 19.

Successful spawning events were previously documented in Pools 18 and 19. We are therefore trying to determine whether successful spawning may be occurring further upstream. Monitoring for juvenile Asian carp was conducted at several possible nursery sites in Pool 16 and 17 during 2013. A total of 1,194 fish representing 34 species were collected during 24 mini-fyke net-sets that cumulatively totaled 447 hours of fishing effort. Asian carp were not observed in any of the catches. However, gravid (mature) adults were collected at two sites in Pool 17 with gill nets. Reproduction monitoring will continue in 2014 and 2015 to determine if successful spawning events are occurring upstream of Pool 18.

This project is by far the most thrilling research project I have led and I look forward to how much we can learn from this. These fish can move great distances and are detrimental to native species. If we understand movement patterns of these species, then we may have a chance at impeding or slowing the spread of Asian carp upstream. We will conduct a full year of sampling in 2014 and should be able to hit the water running this year … once the ice melts!

Contact Info: Kyle Mosel, 608-783-8429, kyle_mosel@fws.gov
Find a Field Notes Entry

Search by keyword

Search by State

Search by Region

US Fish and Wildlife Service footer