College of Liberal Arts

University of Mississippi

Research Takes Hits for Science

University of Mississippi student Orathai “Nok” Pongruktham has been hit in the head by a fish many times, all in the name of research.

The fish, better known as the Asian Carp, or more specifically, the Silver Carp, has been called the flying fish of the Mississippi River by those who do not know better.

Dr. Clifford A. Ochs, Associate Professor of Biology

“Last time we went out on the lake, it was terrifying because they jump,” said Pongruktham, who is a graduate biology student at UM. “Hundreds of them jump at a time.”

Pongruktham said sometimes it gets so bad that her professor Clifford Ochs has had to protect her from the leaping fish, which can grow as large as 60 pounds.

“They hurt,” Pongruktham said. “We sometimes come back from the lake bloody.”

Ochs admitted, however, that the leaping is not always a complete negative.

“We have two primary ways of catching the fish for our research,” Ochs said. “Anything that jumps and lands in our boat becomes our fish. We also work with some commercial fishermen.”

Silver Carp is an invasive species from China that was placed in catfish farms to help control algae in the 1970s, and researchers are not sure how they got into the river system.

Now, it is estimated that hundreds of thousands of them are in the river, and Ochs said they are likely here to stay.

“They are like kudzu,” Ochs said. “They are not going away.”

The team’s research is centered at the Army Corps of Engineers base at Forest Home Chute near Vicksburg. The UM research team, which received a $116,000 grant, is in its third year of funding.

Once they get the fish, the two plankton experts and their assistants hand them off to a fish expert, who anesthetizes and dissects the fish.

For their research, Ochs and Pongruktham are primarily interested in the carp’s “stomach.”

“They have a large digestive tract instead of a stomach,” Pongruktham said. “It is a big pack of guts — 25 feet long.”

The research team is looking to see what plankton the Asian Carp is eating.

“We are taking samples from the upper portion of the digestive tract,” Ochs said. “There are lots of ways that this fish can change the food web, and we want to study how.”

Ochs said what the fish does not digest can also be interesting.

“Also, we are looking lower in the tract to see what they are unable to digest,” Ochs said. “Certain kinds of algae seem to be able to travel through the carps’ system and continue to grow. These types could actually benefit from the fish’s presence.”

Pongruktham said this is not always the most fun part.

“We have to get the poop out to see what they eat,” she said.

Ochs said that some smaller types of algae benefit and could grow more plentiful. However, fish that also eat the same type of plankton the carp eat could be in trouble.

“One example is the paddle fish, which is an iconic fish of the Mississippi River,” Ochs said. “There is concern that its population could become unhealthy. This also has an effect on fish that feed on these types of fish.”

Ochs said the Asian Carp could also hurt the pocketbooks of commercial fishermen of the Mississippi River. Kentucky is trying to market the fish as Kentucky Tuna and sell it as food, since the fish is likely here to stay.

Ochs said he had yet to try one of the fish, but Pongruktham said they were good.

“It was very tasty,” she said. “It is a bony fish, but good.”

Ochs said another aspect of his research that could be interesting is helping China in repopulating its waterways with the fish, which is a staple food in its native country.

“They are having problems growing their numbers due to water quality,” Ochs said. “Some of what we learn could be important to the Chinese as they attempt to regrow the population.”

The issue of keeping the Asian Carp out of the Great Lakes is one of the most important debates concerning the fish, Ochs said.

Illinois, which has a canal that connects the lakes to the river system, is trying to come up with a way to keep the fish out without closing the canal. Several states, including Michigan, have sued Illinois in an attempt to get the canal closed in order to keep the carp out.

“They could already be there,” Pongruktham said. “We just may not know yet.”

Pongruktham joined the project in 2006, when the research was funded on a trial basis, and she said it was a good fit for her. Ochs said the Thailand native is a better microscopist than he.

“I have better eyes and can see what he cannot,” Pongruktham said.

She said she was having fun doing the research.

“It does make me wonder why I am still doing it, since this is not my thesis,” Pongruktham said. “But it is very interesting research, and it does pay for me to go to school.”

Pongruktham said she wants to continue to do research when she graduates, and she hopes to continue to devote her time to rivers.

“I’m looking for a post-research job somewhere, maybe in Asia,” Pongruktham said. “I plan to keep studying plankton and river ecology. Maybe, one day, I will teach.”

from DM by Cain Madden