While we have a varied and interesting native fish population in Indiana, it is the alien fish that have attracted the most attention in recent years. At the top of this list are the Asiatic carp. Their invasion has already had a very deleterious effect on our native fish, and sad to say this may be only the beginning of the trouble they may cause.
Now carp and even goldfish have been a part of the Hoosier fauna for many years. It is these new additions that have caused the most concern. The common carp has been with us for a long time and I have seen goldfish in several bodies of water on a number of occasions.
The common carp is found all across Indiana and can reach a weight of over 70 pounds. The state record is 43 pounds. While the goldfish is not this large, it can be up to seven pounds in weight.
The four species of Asian carp that have now reached our state are the grass carp, bighead carp, silver carp, and the most recent, the black carp. Escapees from aquaculture in some southern states have been the chief culprit in the invasion into the rivers of not only Indiana, but many other states.
The grass carp has also been introduced as a weed control measure in a number of our Hoosier lakes. It has been reported to be able to consume up to 90 pounds of vegetation in a single day. Apparently they now are not only found in several of our lakes, but also in both the Wabash and White River.
The bighead carp came to the United States in 1972. It was brought in to Arkansas to eat plankton in some fish farms. Some escaped and have now extended their range into several states, including Indiana, where they are now found in both the White and Wabash as well as some other of our streams. The fight is now on to keep them out of the Great Lakes. They can grow to reach a weight of nearly 90 pounds.
The silver carp came to Arkansas as early as 1973. It also escaped and spread the same as the bighead and is now also in our Hoosier rivers. It does not grow as large as the bighead, but can grow up to 60 pounds and a length of over three feet. That is still a very big fish.
The black carp also came to America in the 1970s and escaped in Missouri in 1994. It is less common in the waters where it is now found. As with the other carps, it can become a large fish, up to 80 pounds.
The main threat from Asian carp is the huge population numbers that can occur where they become established and the food they eat. All feed upon zooplankton, phytoplankton, and even mulluscan species. This combination is the cornerstone of the food supply of many of our native fish and prodigious numbers wipe out much of the food that is so important to our river and stream fish.
I’m afraid they may even change the very structure of our Indiana rivers and result in the demise of several of the species of fish Hoosiers like to catch.
I have had firsthand knowledge of how many of these carp now exist in both the Wabash and the White rivers. I first became aware of these carp when some fisherman brought me a large fish that had jumped into his boat. I did not know what it was, but went to a fish expert. He had to also go to someone else to learn its identity.
Since that first encounter I have seen hundreds jumping at the sound of a boat motor in both the Wabash and White rivers, and I have had several jump into the boats I was aboard. It is indeed something to experience. Let us hope they can be controlled before it is too late.