A long time, loyal reader and big supporter of this website sends the link to the "buttoned" article. The Committee explains:
"The dolphins fled a pod of orcas, also named killer whales, in abject fear and terror. Few sea creatures have the ability to move at the velocity of a dolphin, which can reach speeds high enough to become painful because of the pressure generated by fast movement through water. For this reason dolphins and porpoises often leap above the surface when swimming quickly for short periods. Orcas can reach thirty knots, or thirty five miles or fifty five kilometers per hour and maintain this velocity for quite a distance. Because of their size, orcas do not feel water pressure to the extent a dolphin or porpoise experiences discomfort.
There are many more dolphins in the seas of Earth than orcas, thus many dolphins have never seen a killer whale or a pod of them. In this case, the dolphins observed an orca pod pursue prey, and fled in fear, even though the dolphins were not the target.
Dolphins are accustomed to outrunning and outmaneuvering nearly any sea creature, but this does not include the orca. Killer whales have virtually no enemy, equaled in strength and killing ability only by a sperm whale. The latter have no interest in orcas, nor do orcas reciprocate. Sperm whales feed on giant squid at great depths.
When the sea lion the target of the orcas was attacked, a few dolphins attempted to intervene in its defense but were quickly repelled. The dolphins fled the perceived attack, but panic set in across the dolphin pod when the orcas could not be outrun, the orcas chasing the interfering dolphins to the point the smaller creatures would leave the larger orcas alone.
The proximity of the island offered the only possible escape & refuge; the dolphins took it. The reason several of them returned to the beach after being dragged back into the water was the ongoing terror still felt by returning to the proximity of monsters forty to fifty times their weight and four to five times their length, able to outrun them with ease.
By the time humans discovered the beached dolphins, the previously distant and invisible orcas, who encountered the large dolphin pod approximately one human mile from the island, were long gone.