YEREVAN, DECEMBER 1, ARMENPRESS. Off Patagonia, Chile, 337 whales were found dead, in the largest whale beaching ever recorded. As “Armenpress” reports, according to National Geographic, the animals were most likely sei whales, and it's not yet clear to scientists what caused the mass die-off.

The whales were first discovered in June, and scientists had planned to report their findings in a scientific journal. But the news has just been leaked in Chilean media, according to National Geographic.

The marine mammals lie in an extremely remote fjord, and that location, combined with rough seas in the area has limited researchers from the Universidad de Chile and Consejo de Monumentos Nacionales, in Santiago, to aerial observations of the carcasses, many of which have already decayed greatly.

According to the National Oceanic and Atmospheric Administration (NOAA), sei whales are "great whales" in the baleen family. They can reach 60 feet long and weigh in at 100,000 pounds. The great sea creatures are considered endangered throughout their range, which includes temperate waters in the Atlantic, Pacific and Indian Oceans.

Not much is known about their movements, and they "may unpredictably and randomly occur in a specific area, sometimes in large numbers," according to the NOAA.

A marine scientist posited to IB Times UK that the whales were likely already dead or dying when they washed ashore.

The deaths were "probably caused by individual whales being exposed to similar circumstances, leading to their death," researcher David Lusseau told the publication. "It is likely also that only a proportion of the dead whales have stranded, so this is an underestimate of the number of whales that have died in a very short event."

Next researchers will try to reach the animals on foot, racing against the fast-decaying corpses, to try to determine what killed them.