By Pete Thomas/GrindTv
Surfers and beachgoers in the Mexican Border city of Tijuana were witness to a rare spectacle Monday, involving killer whales that appeared just outside the surf zone and began to harass dolphins.
Eastern Tropical Pacific killer whales, which are found off Mexico and Central America, are not commonly seen off the northern Baja California coast–especially so close to shore.
Carlos Bravo, a photographer who captured the images for use with this story, said lifeguards and locals said they “have never seen anything like it.”
A report from Alan Williams on the Orca Network Facebook page quoted locals as saying, “This has never happened.”
The killer whales are not believed to be “transient” orcas from California. Those mammals, which prey on dolphins and other marine mammals, have never been documented in Mexican waters.
Eastern Tropical Pacific killer whales, which have not been separated into distinct ecotypes, also are known to prey on marine mammals. They've been documented in U.S. waters, as far north as Catalina Island, according to killer whale researcher Alisa Schulman-Janiger.
The killer whales were traveling in two groups of between four and seven, and were spotted less than 100 yards off Playas de Tijuana, just south of the U.S.-Mexico border.
Williams stated: “A surfer and some others reported that they ‘ate a dolphin’ and described them holding it in their mouth and ‘throwing it about,’ which sounds [like] typical behavior. I didn't see it, but the gulls and scavenger birds were swarming to feed on some leftovers of something, and there are or were plenty of dolphins here.”
Bravo said he received a call at 9 a.m., and arrived at 9:20. He saw only one of the two groups and said he watched them tossing a dolphin, presumably teaching younger members of the pod how to hunt and kill, until about 9:45.
Both reports said the killer whales traveled west, toward the Coronado Islands, before disappearing from view.
Williams wrote: “A surfer in black wetsuit was in the water, and 3 large Orcas approached him in a semicircle to about 30 yards/meters, and each in turn did a ‘spyhop’ maneuver, wherein they surface in a high vertical posture and hover high up for a few seconds–perhaps threatening?
“Or perhaps just to look, or to announce their presence or claim territory. It was quite beautiful, and he got out quickly.”
Researchers are hoping that by looking closely at photos they’ll be able to match at least one individual with others in a photo-identification catalog of Eastern Tropical Pacific killer whales.
NOAA has identified about 240 individuals.
Above all else, I tend to analyze all sociobiological data through the laws of Evolution. Whereas I look to mutation and genetic drift as being the most probative on "why a species appears as it does," I would respectfully submit- particularly with higher order mammals- Natural Selection is the most useful Evolutionary "law" to understand "why a species behaves as it does." As Darwin was careful to acknowledge, Natural Selection may be aptly summarized as the retention of favorable traits over those which are injurious.
So let us dispassionately analyze the behavioral data described herein.
In short, the top Apex predator is- in no uncertain terms- engaging in what appears to be the equivalent of a "war" on its lesser brethren in an overt attempt to inculcate fear. Let us not forget that the "prey" is arguably as highly intelligent as the "predator." As such, (bear with me) the evidentiary "law" of "effect on the listener" comes to mind. In other words, I'm not so sure that the data here is not unlike the non-hearsay analysis for "effect on the listener." It is not proffered as "evidence of just consumption" but, rather, the ACT itself is, well, a form of inter-specific "political speech."
Say, it seems more to me like Chimpanzee attacks observed in Tanzania on OTHER CHIMPS (e.g., despite some consumption, it is more about controlling available resources than serving metabolic need) than when Chimpanzees attack their "lesser" Monkey brethren (i.e., mostly consumption driven, even if the {Colobus Monkey] meat is carefully divided to reinforce social hierarchy).
Here, I am inclined to think these Orca are "driving the [Dolphin] prey" away from the OTHER RESOURCES in the vicinity they compete over by killing a few of the dominant and/or younger Dolphins.
Simply put, perhaps these recent instances of Orcas killing other Dolphins ACROSS THE PACIFIC is much more a FUNCTION of SELECTIVE FORCES pressing down upon the Orca species- which are, not coincidentally, proximately CAUSED by an IMBALANCE of the OCEANIC FOOD CHAIN, i.e., depleted fish stocks from trawling, coupled with industrial pollution and Climate Change.
Of the three, perhaps the fact larger pelagic fish are being cleared out faster than they can reproduce themselves is directing the Orca to take out the Dolphins under the same rationale that leaves bullet holes in some unlucky Sea Lions.
Incredibly, despite the very REAL THREAT OF TUNA EXTINCTION, there is no reprieve from mankind. As by catch struggles helplessly to avoid more waste, futilely, on such a longline.
As for industrial pollution, not unlike Tanzania "taking steps to protect its wildlife" because IT IS FAR MORE VALUABLE WHOLE and ALIVE than bagged and stuffed, so too, are mankind's SHARED OCEANIC RESOURCES far, far more VALUABLE UNDEFILED BY HARMFUL INDUSTRIAL POLLUTANTS than the "cost" of THE WORLD COMMUNITY subsidizing SAFER MEANS TO IRRIGATE/HARVEST CROPS…much less HARVESTING OUR ENERGY.
The Orca are taking out their competitors as a preemptive measure.
Just wait until the pelagic sharks with nothing to eat start eating humans via "hit and run" at their pleasure.
"After the event, even the fool is wise."- Viscount Symonds
Posted by: drudown | Nov 19, 2014 at 01:39 AM