Coastal researchers, fishermen, fishery managers and educators teamed up to understand changes in shrimp populations in response to shifting environmental conditions in estuaries.

The Project

Shrimping has deep cultural and economic ties to the South Carolina and Georgia coasts, and the southeast US Atlantic coast region as a whole. However, over the past two decades, commercial shrimp landings have been highly variable. Fishery management agencies, extension offices, and several southeastern Reserves have identified the need to better understand how shrimp populations are responding to changing environmental conditions, including warmer winters and altered salinity regimes.

To do this work, a diverse team with members from universities, fishery management agencies, fisheries extension offices, and Reserves came together to form the Lowcountry Shrimp Collaborative. The Lowcountry Shrimp Collaborative used a comprehensive approach to examine how environmental conditions in estuaries are affecting abundance and timing of shrimp populations throughout the region through examination of each stage of the shrimp life cycle. Together, the Collaborative:

• Analyzed and synthesized numerous ongoing, long-term (30+ years) datasets on multiple shrimp life history stages (postlarval, juvenile, sub-adult, adult, commercially harvested) and environmental conditions (water quality, including System-Wide Monitoring Program data);
• Conducted field sampling targeting shrimp and their prey in salt marsh creeks during spring and summer seasons, over two years, at three southeast Reserves;
• Ran controlled seawater laboratory experiments to understand the impacts of competition for limited resources between shrimp species during their overlapping periods of estuarine residency; and,
• Interviewed commercial shrimpers based in Georgia and South Carolina, to better understand historical changes in, and perceptions of environmental impacts on, the shrimp industry in the southeast US.

The project found that estuarine water temperature is rising across the region, mainly driven by increases during winter months. Warming temperatures can alter the life histories of shrimp, including shifting body size, altering the timing of migratory cues, and modifying habitat use. These warmer temperatures are also resulting in longer shrimping seasons with shrimpers often able to continue harvesting well into January. These results were confirmed by observations shared by shrimpers, who joined for a project wrap-up event where the team presented results and engaged in lively discussions about research needs and opportunities for collaboration between researchers, managers, and the industry.

The Impact

• Formed a deeply knowledgeable and experienced Collaborative of researchers, managers, and educators that is well-positioned to continue studying shrimp population dynamics in the southeast US when opportunities arise.
• Established strong and growing relationships with fishery managers and shrimp industry end-users who are interested in future research collaborations with the Lowcountry Shrimp Collaborative.
• Developed the next generation of researchers, managers, and educators focused on estuaries and their associated fisheries by providing research experiences for graduate (3) and undergraduate (25) students, with some students receiving additional research support from shrimp industry-affiliated organizations.
• Used a systems approach to understanding the connections between inshore estuarine habitats, the shrimp populations that utilize them during early life stages, and the shrimping industry that depends on both.
• Conceived a potential roadmap, applicable for shrimp and other fishery species in the southeast US and beyond, for conducting comprehensive investigations of fishery species with complex ocean-estuary life cycles that involves utilizing multiple long-term datasets focused on individual life stages, with datasets collected by distinct research groups and management agencies.
• Contributed significantly to the scientific literature on estuarine habitats and the ecology of shrimp, namely the impacts of changing environmental conditions on shrimp habitat use and population dynamics, over both short (seasonal) and long-term (decadal) time scales.