By Kelley Luikey | What do fish-whacking, kerplunking, pinwheeling and strand feeding have in common? They are all terms used to describe the resourceful feeding methods of dolphins.
The common bottlenose dolphin (Tursiops truncatus) is a charismatic and beloved sight in our Beaufort waterways. Intelligent and social – they travel, feed, play and rest in groups and are active throughout the day and night. Local residents and visitors alike are fortunate to have the opportunity to frequently observe these beautiful creatures in their natural habitat.
Some of the most remarkable behaviors to witness on our inshore waters are their incredible feeding methods.
Bottlenose dolphins consume approximately five percent of their body weight a day; roughly 15-30 pounds of fish, squid and crustaceans depending on the size of the dolphin. They employ a diverse array of foraging strategies, many of which are complex in nature and likely learned. Some of these behaviors involve single animals while other techniques involve dolphins working together in a coordinated effort. With flukes slapping, water splashing and fish leaping, many of these feeding methods create an impressive visual and acoustic display that an observer will not soon forget.
Fish-whacking, kerplunking and pinwheeling (yes, these are actual scientific terms) are just three examples of dolphins working alone to capture prey. Fish-whacking occurs when a dolphin will debilitate a fish by using its flukes to whack the fish. The prey is often hurled it into the air and stunned, thereby making it a breeze for the dolphin to retrieve and eat. Kerplunking is another method in which a dolphin will use a fluke-slap to produce a “kerplunk” sound. The tail splash creates bubbles under the water, flushes the fish from their hiding spots and makes it easier for the dolphins to detect them. The pinwheel strategy occurs when the dolphin rotates to swim on its side, accelerates at an extremely fast rate and circles schooling fish into a tight circumference in order to intercept the fish. This high speed pursuit creates an astonishing exhibition of agility and maneuverability.
Perhaps one of the most impressive feeding techniques to observe in our area is a type of cooperative feeding behavior that is unique to South Carolina and Georgia. This method is termed strand feeding and is so-called because the dolphins partially strand themselves temporarily on the shore to feed.
First documented in 1971 (Hoese) in the shallow marshes of Georgia, strand feeding involves a group of dolphins operating as a unit to capture schooling fish. Working at low tide, the dolphins synchronize their movements underwater to corral the fish towards a bank. The dolphins then make a strong push towards the shore, creating a bow wave and forcing their prey onto the mud. The sheer force of them hurling their bodies towards the shore as a group is an extraordinary display and not without risk. The dolphins consume the fish on the bank and must quickly slide or shimmy back into the water before they become stuck in the mud and face a host of hazards.
A similar foraging strategy called beach hunting has been noted in bottlenose dolphins in other locations around the world. However, it involves solitary dolphins rather than a synchronized group and does not appear to be practiced on a regular basis.
Dolphins utilize a repertoire of techniques to hunt prey, all of which are testament to their intelligence, agility and maneuverability. The patient Lowcountry observer, whether out on the water by boat or simply watching from shore, can observe our local bottlenose dolphins navigating the intricate maze of our tidal marshes, creeks and rivers.
The lucky onlooker may be rewarded by witnessing one of their ingenious foraging displays…a truly spectacular experience.
Follow more of Kelley’s fabulous local nature photography on her Facebook page, at Nature Muse Imagery.