Dean Grubbs' Interpretation of Killer
Whale/White Shark Encounter
14 October 1997
Dean Grubbs, a graduate student at the Virginia Institute of Marine Science, Gloucester Point, Virginia, just returned from the Farallon Islands and updates us on the recent killer whale/white shark encounter. |
| Ken Goldman and myself arrived to the islands just as the Orcinus-Carcharodon encounter occurred. We saw very little first-hand other than glimpses of Orcinus from behind the rocks. However, I have seen all of the footage taken and heard the accounts from Pete Pyle, Scott Anderson, and Mary Jane Schramm. Since they are still on the island and are not tuned in to elasmo-l, I will make a few corrections to the story the media circus has been spreading and give you the interpretation (in short) of the chronology of events which seems most likely. |
| There were two Orcinus seen off the Sugar Loaf on the North side of the South Farallon Islands. One was larger than the other but both were supposedly mature females. There was no calf present. The two whales were said to have killed a Zalophus (California sea lion) and were 'toying' with it for a while. A small Carcharodon came on the seen, probably to investigate the kill and try to steal a hunk as is normal had the kill been made by another white shark. The smaller Orcinus apparently did not accept this intrusion with open pectorals and proceeded to attack the Carcharodon (it was most definitely a Carcharodon). It swam through the water pushing the shark along as it writhed in its mouth. The whale was holding the shark anterior to the pectorals. The whale eventually dropped the shark and it sank to the bottom. The shark's body cavity must have been torn open on the left side as there appeared to be internal organs such as intestine trailing from the shark as it was seen in the footage sinking upside down to the sea floor and a large portion of the shark's liver was left floating on the surface. The shark appeared to be completely intact otherwise. The Orcinus then spent time pushing the liver around on the surface but never really fed on the shark at all. So there was no feeding of a calf, there was no ripping the shark to shreds, and one can contemplate at length the cause of the attack. |
| So, having said this, what does it mean scientifically? Virtually nothing! This is the first time Orcinus has ever been seen this close to the islands according to Pete Pyle and have never been seen feeding. According to cetologists in southern CA the Orcinus in question, which was billed as a calf by the media, was first observed as a young adult female in 1982 though there is debate over the size of the animal. She has been observed virtually every year since and has never been seen north of Los Angeles until this incident. All of the Orcinus in the region are transients that don't usually come close to shore so the two species probably rarely encounter each other so such an incident makes for dramatic media footage and mildly interesting discussion, but is virtually meaningless ecologically. Show me footage of a large Physeter feeding on an adult Architeuthis. |
| Anyway, that's my opinion and I hope this clears up some of the questions regarding the incident.
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