Dolphins are recognized for their intelligence and complex social structures, allowing them to develop sophisticated hunting techniques. Among these methods, strand feeding is a highly specialized and unusual behavior. This strategy involves a group of dolphins deliberately pushing fish onto a shoreline and then temporarily launching themselves out of the water to capture their prey. The cooperative nature of this hunting requires precise coordination and learned knowledge.
The Mechanics of Dolphin Strand Feeding
Strand feeding is a coordinated group effort relying on precise timing and a specific environment. The process begins with a small pod of dolphins corralling a school of fish, such as mullet or menhaden, toward a shallow, sloping bank or mudflat. Once the fish are concentrated, the dolphins form a line and accelerate rapidly toward the bank in unison.
This synchronized rush creates a powerful bow wave, a hydraulic force that pushes the trapped fish onto the exposed bank. Following the wave, the dolphins surge forward, momentarily stranding their bodies on the mud or sand to snatch the disoriented prey. They execute this maneuver quickly, sliding back into the water to avoid becoming permanently beached.
This technique is a high-risk strategy, as dolphins are not built to support their weight on land. If the retreat is not executed perfectly, a dolphin risks injury, sunburn, or death. Observations show dolphins typically strand on their right side, resulting in noticeable dental wear from repeated contact with the abrasive substrate.
Primary Geographic Locations
Strand feeding is globally rare, observed in fewer than ten locations worldwide, which heightens the significance of these primary hotspots. This unique foraging behavior is overwhelmingly concentrated along the estuarine and coastal regions of the southeastern United States. The practice was first documented in a Georgia salt marsh in 1971 and remains most frequently observed in the US Lowcountry.
The most established area for this behavior spans the tidal creeks and salt marshes of South Carolina and Georgia. Specific locations include the waterways around Kiawah Island and Seabrook Island, and the Beaufort County area, encompassing Hilton Head, Bluffton, and Port Royal.
This 300-mile stretch of coastline provides the ideal environmental conditions for local dolphin populations to practice this behavior consistently. Outside the US, strand feeding has been reported in isolated areas, including the Gulf of Guayaquil in Ecuador and occasionally in the Louisiana salt marsh. However, the South Carolina and Georgia regions host the most well-studied occurrences of this complex hunting technique.
Ecological Factors and Specific Populations
The dolphins engaging in this hunting are Atlantic bottlenose dolphins (Tursiops truncatus), specifically coastal resident populations. Residency is a defining factor, as the behavior is a learned cultural tradition passed down from mother to calf. It requires an intimate knowledge of local bathymetry and tidal patterns that only resident animals possess.
The physical environment must meet specific criteria for strand feeding to be viable. It requires areas with a large tidal amplitude, which exposes extensive mudflats and creates steep, shallow slopes along the creek banks. For example, the Beaufort, South Carolina, region has an average tidal range of about 8.5 feet, necessary to concentrate prey in the narrowing waterways.
The precise slope of the bank is paramount; dolphins prefer a gently inclined surface that allows them to slide out and quickly slide back in using gravity. This is typically observed on exposed mud or soft sand banks. The behavior is closely tied to the tidal cycle, occurring most often within the two hours before and two hours after low tide, when water levels are lowest.