Researchers Propose Strategic Measures to Curb Invasive Carp Spread.

Efforts to halt the advance of invasive carp into sensitive U.S. waterways are receiving renewed attention, as researchers from South Dakota State University (SDSU) offer strategic recommendations to slow the spread of this destructive species. With federal backing and increased scientific scrutiny, experts are zeroing in on prevention as the most cost-effective solution to a growing ecological challenge.

In April, the federal government committed to additional funding to support the U.S. Army Corps of Engineers in strengthening barriers to prevent invasive carp from entering the Great Lakes through Lake Michigan. This $1.2 billion project underscores the seriousness of the threat posed by the fish, which were originally introduced to the U.S. in the 1970s to manage algae in commercial fishponds. However, flooding events allowed the fish to escape, and they have since proliferated across major Midwestern waterways, significantly disrupting native ecosystems.

At the forefront of research efforts, SDSU’s Department of Natural Resource Management, led by assistant professor Alison Coulter and graduate research assistant Hannah Mulligan, is investigating both the ecological impact of invasive carp and viable prevention methods. Their latest study, recently published in the journal BioScience, explores how different states and countries are combating the spread of aquatic invasive species, particularly through the live baitfish trade.

With an estimated value of $1.56 billion in the U.S., the baitfish industry represents a major vector for the unintentional spread of invasive species. One of the main challenges is that young invasive carp can easily be mistaken for native baitfish due to their similar appearance at early life stages. This makes the trade a high-risk pathway for further contamination.

“Prevention is the most cost-effective method to minimize human-facilitated introductions and the subsequent harm caused by invasive species,” Mulligan noted. However, she emphasized that current prevention efforts are inconsistently applied across regions and timeframes. The study reviewed measures such as regulation, education, and inspection to determine best practices under constrained budgets.

One promising solution is the installation of bait disposal stations at water access points, encouraging anglers to properly dispose of leftover bait instead of dumping it into lakes and rivers. While such dumping is illegal in many jurisdictions, it remains a common practice due to misinformation or convenience.

Mulligan explained that many anglers mistakenly believe that releasing unused bait benefits sportfish populations or oppose euthanizing baitfish on ethical grounds. However, releasing baitfish—especially those from different regions—can introduce invasive carp, zebra mussels, and aquatic pathogens into new ecosystems.

To address this, the study recommends targeting bait wholesalers for inspections, as they represent a smaller, more manageable group compared to the larger network of retailers and anglers. Additional suggestions include implementing baitfish harvest restrictions and providing online training about aquatic invasive species in regions with fewer bait outlets.

“Focusing on wholesalers allows us to reduce risk early in the distribution chain, similar to conducting border checks at points of entry,” Mulligan said. “It’s more practical than relying on anglers to spot invasive species in their bait buckets.”

Despite the challenges posed by limited funding, the researchers stress the importance of interagency collaboration. Mulligan pointed to regional panels that share information and resources as effective models for broadening the impact of prevention strategies. She also advocated for greater access to currently unpublished materials like management reports and outreach tools.

“By prioritizing management of the live baitfish trade and promoting the sharing of cost-effective practices, we can enhance regional coverage and slow the spread of aquatic invasive species,” she concluded. Although individual states must manage their own prevention efforts, success ultimately depends on consistent coordination across state lines.

Source:https://phys.org/news/2025-04-invasive-carp.html

This is non-financial/medical advice and made using AI so could be wrong.