From a cliff above the tiny cove, a stocky, bald man could be seen between tightly drawn lengths of green tarpaulin, a metal rod in one hand, and something long, black and smooth wriggling helplessly under the other.

Suddenly, the waters come alive with frantic splashes as the two objects meet and the water the man’s wading in turns a purplish red.

This was the culmination of the first dolphin cull of the 2009 season in Taiji, the fishing village in Wakayama Prefecture that gained worldwide attention following the release of the Oscar-winning documentary “The Cove” that year.

The method employed — impaling the dolphins behind the blowhole to sever the spinal cord — seemed barbaric, but, according to a paper by Japanese researchers, it is more humane than the more random hurling of harpoons from boats employed previously in Taiji’s drive hunts.

Now, a new study by scientists in Britain and the U.S. rebuts those claims. “Our analysis shows that this method does not fulfill the internationally recognized requirement for immediacy,” said University of Bristol Veterinary School professor Andrew Butterworth, lead author of the paper. “It would not be tolerated or permitted in any regulated slaughterhouse process in the developed world.”

Butterworth and his team assessed video footage of the Taiji cull, filmed covertly in 2011 for the German conservation group AtlanticBlue, in order to verify a study penned in 2010 by Toshihide Iwasaki and Yoshifumi Kai of the Fisheries Research Agency and Taiji Fisheries Association, respectively.

The Japanese report claimed that tests of this method had seen considerable reductions in the time taken for a dolphin to die, leading to further use from December 2008. In the case of four striped dolphins, death occurred in as little as five seconds instead of the 300 seconds needed using conventional practices, according to the report.

Examining the 2011 video footage, however, Butterworth and his team found that the time taken was in fact far longer, with one striped dolphin still moving 254 seconds after first being impaled.

“The disparity . . . calls into question the confidence that can be attributed to the data provided in the Iwasaki and Kai report,” says the study.

The criteria for death used in the Japanese report — given as “termination of breathing and movement” — is also flawed, it adds. Immobility could occur in any animal that had just had its spinal cord severed, while nonrespiration could simply reflect the dolphin’s ability to hold its breath for long periods.

The new paper also scrutinizes other aspects of the Taiji drive, such as the tethering of the animals to boats by their flukes to herd them into the culling cove. “From a scientific, humane and ethical perspective, the treatment of dolphins in the drive hunts sharply contradict current animal welfare standards employed in most modern and technologically advanced societies,” said the coauthor of the paper, Diana Reiss of Hunter College at the City University of New York.

A Taiji fisheries official who asked for anonymity insisted that footage seen by Butterworth and his team may simply have shown a one-off example, featuring less-experienced workers.

“Just as with cattle slaughtered by pistols shot by humans in the West, it is difficult to attain a 100 percent success rate,” he said. “On occasion it’s possible that the spear will not precisely hit the mark, but overall, death is instantaneous. . . . Picking up on one instance that shows this not to be true is just another example of one of the strategies employed to further the claim that we in Taiji are liars.”

Reiss admitted that there is a paucity of clear video footage of the culls such as that provided by AtlanticBlue due to the increasing tendency to shield them from public view, but that an abundance of other footage showed dolphins “flailing and struggling . . . well beyond a few minutes in this practice.”

“Our analysis also addresses the entire process of killing, including the rounding up of the dolphins at sea, the confinement in a cove for sometimes days, and then the actual dragging and herding to shore where they are killed in front of their kin and close allies — all of which is extremely stressful and inhumane,” said Reiss, who has studied the cognition and communication of dolphins for more than 25 years.

“In the U.S. and the U.K., regulations and guidelines governing the humane treatment and slaughter of animals prohibit the killing of an animal in the presence of other animals.”

The Taiji fisheries official said he had no knowledge of the regulations, but added that if they became international requirements they would consider implementing them.

Another unnamed Taiji fisheries official who tried to hinder this reporter’s coverage of the cull in 2009 lambasted what she called “hypocritical” and “racially motivated” condemnation of the hunting methodology, saying kangaroo culling in Australia was far more brutal and that spinal cord transection was also practiced on chickens and other animals in the West.

Researchers say this is a chalk and cheese comparison. With large animals such as dolphins, accuracy of spinal cord severance is problematic, they say.

“To penetrate the spinal canal, the rod would have to accurately enter the space between vertebrae . . . or to damage the cervical vertebral bone sufficiently to allow spinal cord severance,” the U.K.-U.S. study says. “Either of these processes, if carried out with a rod after passage through muscle and other tissues, is unlikely to be applied with a high degree of precision.”

As a result, exsanguination becomes a drawn-out process, inducing first paraplegia and death through trauma and gradual blood loss, the study continues. The process is prolonged further by a practice introduced in 2009 whereby a wooden peg is inserted into the wound. This is undertaken, say Iwasaki and Kai, to prevent excessive water contamination. “It also opens up a potential avenue for the commercial use of the blood,” their report says.

Butterworth and his coauthors say that the method described “does not conform to any recognized mechanism for bringing about death in accepted humane slaughter or euthanasia practice in large mammals.”

The Taiji Fisheries official countered: “Who decided these (recognized mechanisms)?”

The new study has its critics, with expert Lori Marino of Emory University calling the decision to focus on the culling method “unfortunate” as it implies “there is a humane way to end a sentient life.”

“At very best, these statements are worded in a way that can only lead the average person to conclude that there are more acceptable ways and less acceptable ways to kill dolphins,” Marino said. “The idea that there are proper and improper ways in which to slaughter animals is obviously inconsistent with the recognition that they have basic rights to life and liberty.”

Asked if there are other killing methods that would be considered more humane, Reiss said: “The killing of dolphins is indefensible, given our scientific knowledge of dolphins, which has demonstrated their sophisticated cognitive abilities, including self and social awareness. They deserve global protection.”

Kris Simpson of International Dolphin Watch applauded the new study. “We should ensure that dolphins receive the highest standards of treatment in any hunt, equal to that granted to domestic animals,” he said. “This is clearly not being achieved, nor, under conditions in the wild, is it ever likely to be. Our position is therefore unequivocal; dolphins must not be hunted.”

Despite persistent international pressure, Taiji continues its annual culls, which it calls a cornerstone of a fisheries industry that sustains the small fishing community of 3,200 people.

None of the dolphins slaughtered for their meat are from endangered species, they claim. Bottlenose dolphins are among the cetaceans caught and sold for millions of yen to aquariums in Japan and overseas.

“Of course, overfishing of resources should be prevented,” the Taiji official said. “But I can’t see any problem with using resources that are not endangered and can reproduce.”