University of New Orleans earth and environmental sciences professor Martin O’Connell is fishing for clues in Plaquemines Parish to determine whether tilapia—considered an invasive fish species in the wild—has survived a targeted kill conducted almost 15 years ago.

O’Connell, director of the Nekton Research Laboratory at UNO’s Pontchartrain Institute for Environmental Sciences, has received a nearly $50,000 grant from the Barataria-Terrebonne National Estuary Program for the project in Port Sulphur, Louisiana.

O’Connell’s research involves studying, managing, and conserving aquatic animals in freshwater, estuarine, and marine habitats. His lab researchers examine long-term changes in fish assemblages, responses of aquatic communities to natural and anthropogenic disturbances, and ecological needs of organisms threatened by changing global conditions. Ann Uzee-O'Connell, a researcher in the Pontchartrain Institute for Environmental Sciences, is the co-principal investigator for the grant.

“As a scientist who has studied invasive species most of my career, I am curious to see how well the eradication strategy carried out by LDWF worked,” O’Connell said. “I hope that 14 years after all this happened that we don't find any tilapia.”

Tilapia species are probably the worse group of escaped aquaculture species when it comes to causing ecological and economical damage around the world, O’Connell said. When the area ditches were surveyed for tilapia around 2010, it was estimated that they represented 85 percent of the population.

“This type of quick population growth causes local native fishes to lose both food items and habitat,” O’Connell said.

There are important freshwater species, such as largemouth bass, bluegill and estuarine species like red drum and spotted sea trout that use the areas around Port Sulphur as nursery habitats, O’Connell said.

“It’s bad enough that we are losing so much habitat in Plaquemines Parish to coastal erosion,” he said. “Having another stressor like non-native fishes just adds to the threat to both commercially and recreationally important native fishes.”