BRUNSWICK, Ga. (AP) – Scientists say they have linked four pilot whales found dead on the coast of South Carolina with 17 whales of the same species that died days earlier after beaching themselves in Georgia.

The Georgia Department of Natural Resources said in a news release Monday that photographs of dorsal fins confirmed the 21 dead whales belonged to the same pod.

The agency said 16 of the deadly strandings happened Wednesday around St. Catherines Island, Georgia. An additional pilot whale carcass was later found on Cumberland Island.

Four more dead whales were found Saturday on and near Edisto Beach, South Carolina – about 80 miles (128 kilometers) from the stranding site in Georgia.

The American Cetacean Society says pilot whales are often involved in mass strandings partly due to their social nature.

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