Around here, dolphin regularly engage in an extraordinary learned behavior called “Strand Feeding.”  It works the same way a good Border Collie handles a large flock of sheep. A pod of Bottlenose Dolphin will find a school of fish and cooperatively work to move the fish by circling, corralling and herding them into progressively shallower water, until the school is hemmed in by the shore on one side and a ring of dolphin on the other, cutting off any avenue of escape for the “schoolers”. Then one member of the pod darts into the school, creating a large bow wake that pushes the water and some of the fish flopping onto dry land. Each Dolphin then rushes up onto the mud-bank and, eat its fill of the stranded fish, at least as many as they can grab, while totally out of the water. After all the fish on the bank are taken, the pod retires to deeper water and repeats the operation. Many dolphin “strand feed” in other areas of the world but only on about a 100 mile stretch of coastline around Charleston, S.C. and the Low Country does it happen regularly, daily.

Spartina Grass - Copyright John Zillioux All Rights Reserved

Spartina Grass in pluff mud along the creek

This behavior is not just limited to pods of Dolphin. This evening, I was walking down to the dock head, which is about 350 ft. straight out from shore (see this post for a more thorough description) and stands about 8 ft. above the Spartina Grass heads and oyster bars that spot the shallows, when I saw something very large moving very fast in one of the outflow channels. During a falling tide, when most of the entire expanse of the mud-flats are fully exposed, the only water left is in small erratically winding channels that converge with other progressively larger channels until they form a channel several feet deep and 12-15 ft. wide that empties out into Bohicket Creek, a deep water, fully navigable waterway perhaps 500 ft wide, that separates Johns Island, where I live, from Wadmalaw Island. In the out-going tide an adult Dolphin and a fairly small juvenile were “stranding feeding” in one of the larger channels that empties into the Creek. The juvenile was watching more than taking part in the fun, but the adult was moving a lot of water around and taking fish off the bank with practiced precision and herding other fish towards the juvenile, who caught several as I watched. In the shallower areas, the adult was moving through the soft Pluff-mud at remarkable speeds and only the fastest, and luckiest, fish made it to the safety of the smaller, and shallower connecting channels that were far too shallow for her size. A few Laughing Gulls and a couple Little Blue Herons were also paying close attention to what was going on, but weren’t fast enough to get any fish … though they tried a couple times. After a few minutes, the pair had apparently exhausted the supply of fish in the channel and moved out into the deeper water of the Creek and were gone, leaving only a tiny trail of smoke-like mud in the water pointing in the direction of their leaving.

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