Projects
- Early Life Stages Research
About the project:
- Most of the work on this project happens in late spring and throughout the summer. Invasive carp usually spawn when the water temperature is above 65°F and typically happens after rain causes the river to rise.
- Indiana DNR project partners collect data throughout a large portion of the Ohio River, stretching from West Virginia to southwest Indiana.
- A portion of the eggs and larvae collected are sent to a laboratory for genetic analysis to confirm the exact species.
- Once hatched, young invasive carp grow fast and can reach sizes of 5 to 6 inches by the end of their first summer.
- The research findings help inform agencies on the best areas on which to focus resources to reduce invasive carp spawning and abundance.
Project goals:
- Determine where spawning and reproduction occurs. Indiana DNR works jointly with other partners to collect fish eggs and larvae using a specialized net to determine how far up the Ohio River invasive carp are spawning and reproducing. Tributaries of the Ohio River are also monitored to determine areas where invasive carp spawn.
- Determine where young fish survive to adulthood. Project partners use targeted techniques to capture small, 1 to 5-inch young-of-year (fish that were born during that year) invasive carp. This informs researchers what types of habitat invasive carp prefer, so we can look for ways to lower their survival.
- Investigate why Hovey Lake attracts so many young invasive carp. In collaboration with university and federal partners, Indiana DNR is researching how small invasive carp get into Hovey Lake each year and is looking at ways to limit this from happening in the future.
- Determine the origin of adult invasive carp by using microchemistry. Microchemistry is a tool used by researchers to look at the chemical makeup of a fish when it is a certain age and compare that to the chemical makeup of water in different rivers and streams. Many rivers and streams have a unique chemical signature that can be used to determine where fish may have lived during different years of their lives.
Current status:
- As of 2021, genetically confirmed silver and bighead carp eggs have been collected just upstream of Cincinnati on the Ohio River.
- Most spawning appears to happen in the main channel of the Ohio River, but invasive carp eggs were also collected in the Kentucky River in 2021.
- Most young-of-year invasive carp are collected near Mount Vernon, Indiana in and around Hovey Lake but recently several have been collected in Ohio River tributaries as far upstream as near Rising Sun, Indiana, in 2022.
- Movement and Habitat Use Research
About the project:
- Work for this project is performed year-round. Invasive carp show movement from the main channel into tributaries and vice versa as water level and temperature fluctuates throughout the year.
- There is a vast array of data loggers on the Ohio and Wabash rivers, as well as several of the tributaries of the Ohio River. These data loggers are maintained by Indiana DNR and other partners. New data is downloaded from data loggers approximately every two months.
- Indiana DNR and other partners work to tag invasive carp species throughout different sections of the Ohio and Wabash rivers.
- The information from this project is used to determine how quickly invasive carp are moving farther upriver and to inform fishing removal efforts.
Project goals:
- Understand year-round invasive carp movements within river systems. Indiana, along with several other project partners, has an extensive system of data loggers along the Ohio and Wabash rivers and their tributaries. Through regular data downloads, we can get a sense of when and where invasive carp are moving, not only within the Ohio and Wabash rivers, but also in their tributaries.
- Determine how many invasive carp are moving up or downstream through lock chambers. Data loggers are deployed on nearly every Ohio River lock and dam from Willow Island, West Virginia, down to Smithland, Kentucky. These data loggers help determine how many tagged invasive carp have moved through the dam (up or down river) via the lock chambers.
- Understand when invasive carp are using tributaries. Data loggers located in the tributaries of the Ohio River provide information on when tagged invasive carp are entering and leaving the tributaries for the main stem of the Ohio. Understanding when they use the tributaries, and under what conditions, can help inform when it is best to schedule removal events.
- Monitor how far upriver invasive carp have invaded. As the front edge (farthest upstream detection point) of the invasive carp population expands, detections of tagged fish on data loggers farther upriver can help to inform project partners of where invasive carp have moved within the river.
Current status:
- Very few tagged fish were found to move away from the stretch of river in which they were tagged.
- Adult invasive carp were found to have an estimated 75% chance of surviving each year.
- Most fish movement occurs in the spring, when warmer waters and higher river flows jumpstart spawning activity.
- Early Detection and Evaluation Project
About the project:
- Most of the work on the project takes place from late spring through the fall.
- Sampling consists of both fish community sampling and efforts targeted at just invasive carp. Both are accomplished using boat electrofishing.
- Fish community sampling occurs on the Ohio and Wabash rivers. This work informs where invasive carp are established on both rivers, as well as how much of the current fish community consists of invasive carp species.
- Targeted sampling for invasive carp is performed on the Ohio River and its tributaries. Fish collected during summer targeted efforts are used to determine the average age of invasive carp within Indiana waters.
Project goals:
- Determine ages of invasive carp in different areas of the river. Aging invasive carp allows DNR to track changes in growth rates and population age structure over time to evaluate the success of management actions.
- Monitor changes in present native fish species for community sampling. Shifts in the fish species found along the river can be an indication that invasive carp may be negatively affecting them.
- Monitor if invasive carp have expanded to new areas of the river. Fish community sampling helps DNR determine which areas of the river are home to invasive carp. It can also help determine if invasive carp are just spreading to that area or if they are well established.
Current status:
- Bighead carp have been found as far up the Ohio River as Stratton, Ohio.
- Silver carp have been found as far up the Ohio River as Twomile Creek, south of Letart, West Virginia.
- Black carp have been found as far up the Ohio River as Brandenburg, Kentucky.
- Control and Containment Project
About the project:
- Most of the work for this project is done from fall through winter and early spring. Invasive carp jump less in colder water temperatures and are more likely to be in the tributaries where it is easier to use nets to capture them.
- Removal efforts are usually accomplished through netting or electroshocking. Sometimes both are used together.
- Indiana DNR helps several project partners with contract fishing programs as needed.
- The priority of this project is to slow the movement of invasive carp upriver and ultimately drive down invasive carp populations.
- Agencies provide oversight to ensure that invasive carp harvest programs cause no substantial impacts to native fish populations.
Project goals:
- Reduce the population of invasive carp species. Both contracted fishing and incentive programs are being used by neighboring states to increase the number of invasive carp harvested from Indiana waterways.
- Stop the spread of invasive carp species. State and federal partners are evaluating different deterrents and barriers to slow the spread of invasive carp.
- Focusing fishing efforts in areas of highest concern. Currently, incentive programs exist on the Wabash River to help increase harvest in underused populations. Contracted-fishing efforts have focused on either the leading edge of invasive carp movement or in areas with highest concentrations of invasive carp to reduce the number of invasive carp moving farther upstream.
Current status:
- Indiana DNR assists project partners with contracted fishing efforts on the Wabash and Ohio rivers.
- Indiana DNR is working to implement new programs to help increase removal of invasive carp from Indiana waters.
- Indiana DNR conducts small scale removal efforts through boat electroshocking.
- Neighboring states, including Illinois and Kentucky, have harvest programs to incentivize increased harvest of invasive carp.