Crayfish Personalities May Be Key to Understanding Water Ecosystems

Dan Aquaculture, Industry News Release, Research, Water

Just like people come in different personalities, animals vary in their behavior. For example, some crayfish can be shier while others are bolder, a University of Florida scientist says.


Image courtesy Lindsey Reisinger, UF/IFAS.

While crayfish are known as those little, lobster-like crustaceans eaten by some as a delicacy in soups, bisques and étouffées and are used by others as fish bait, Lindsey Reisinger and her team want to use the crayfish as a model for how animals’ behavior changes the environment and vice-versa.

Reisinger recently received a $299,865, two-year grant from the National Science Foundation to study the behavior of two types of crayfish – the rusty and the virile. Starting in May, they’ll collect crayfish in several states: Tennessee, Ohio, Wisconsin, Alabama, New York, West Virginia and Connecticut.

While crayfish live in Florida water, researchers are concentrating on the other states because that’s where they think they’ll see the biggest behavioral changes in these two crayfish species.

“Scientists don’t know how important animal personalities are for ecosystems,” said Reisinger, a research assistant professor in fisheries and aquatic sciences at the UF Institute of Food and Agricultural Sciences. “Testing this question in crayfish will let us know whether this is something we should consider more broadly, across different species and ecosystems.”

In some ways, crayfish mimic their counterparts in the animal kingdom. For instance, some may feed more often than others, Reisinger said.

“As scientists and conservationists, we are typically concerned with the influence that different species have on the environment,” Reisinger said. “For example, rusty crayfish are invasive in many areas of the Midwest. They eat freshwater plants, insects and snails and often cause major declines in these plants and animals when they are introduced to new lakes and streams.”

They will test whether crayfish behavior affects the amount of nutrients and energy that get into freshwater ecosystems.

They also want to see how crayfish personalities change across the states and how their environments change their behavior. For example, crayfish can impact freshwater ecosystems by shredding leaves that fall into the water. The remaining leaves serve as a food source for other organisms, she said. This can increase nutrients in the water, she said. On the other hand, fish eat crayfish, hopefully balancing out the ecosystem.

“Crayfish are an important for the movement of energy and nutrients through freshwater food webs,” Reisinger said. “An aggressive and bold crayfish will move around and eat much of the day. They eat dead leaves and plants, shred them into small pieces and those little pieces can be eaten by other organisms. That may change how good streams are at filtering nutrients out of the water. This can also cause declines in the abundance of fish that rely on the habitat provided by freshwater plants.”

Source: University of Florida Institute of Food and Agricultural Sciences