Mystery Surrounds Stranded Whales Who Got Back in the Ocean

Eleven long-finned pilot whales were found by local teenagers, washed up and stranded on the same beach in Canada on Sunday, but only three could be saved.

The Marine Animal Response Society attended the scene in Port Hood, Nova Scotia, and alongside the locals, managed to help three of the whales return to the waves, one of which was a juvenile. The remaining eight, unfortunately, died on the beach.

Long-finned pilot whales are, despite their names, a species of large dolphin. These creatures grow to lengths of up to 19 feet for females, and around 22 feet for males. They are found throughout the Northern Atlantic and across the Southern Hemisphere, the National Oceanic and Atmospheric Administration (NOAA) explains.

These mammals live in close social groups of between 10 and 20 individuals, with a complex social structure. They can dive to depths of about 2,000 feet for up to 16 minutes to feed on fish, cephalopod, and crustaceans.

"It's actually really important it's done in a very specific way to be able to get them all back in the water very carefully, making sure the animals are kept cool, you know, putting water on them, but not in their blowhole, and then trying to get them all out at the same time because they need to go as a group, which is very hard when you have a group this big of animals this large," Marine Animal Response Society executive director Tonya Wimmer told Canadian news outlet CBC Radio's Information Morning Cape Breton.

The exact reason for these whales' mass strandings is unknown, with this species being the most commonly involved in such activity. One of the largest stranding events in history resulted in over 1,000 whales washing up on a single beach in the Chatham Islands near New Zealand in 1918. Several hundred whales are left stranded on these islands each year. Also in New Zealand, ​​more than 600 pilot whales stranded in 2017, leading to 250 deaths.

"Long-finned pilot whales are notorious for these beachings and we know from past research that they can be both naturally occurring (confusion, sick individual, etc.) or human-caused," The Cape Breton Pilot Whale Project said in a Facebook post announcing the strandings.

The strandings can also occur if the whales follow a food source into the shore and become trapped as the tide goes out.

"Whale strandings remain a mystery. We don't exactly know why whales and dolphins do this," wildlife scientist Vanessa Pirotta of the Marine Predator Research Group at Macquarie University, previously told Newsweek.

"Several factors might be at play here, e.g. misnavigation, spooked by something, following a sick leader. There might be many more reasons," Pirotta said. "Pilot whales are social and can be found in large pods at times. Unfortunately, the clock starts ticking when a whale/dolphin strands. The longer they are out of water, the less chance they have at being released. Even if released, there's always a chance they might re-strand."

Wimmer told CBC that there was another pod of the same species close offshore that they were concerned might also strand.

"They're swimming around. They're not actively leaving the area, but there is apparently some bait in the area, some food that they may be eating," Wimmer said. "We're hopeful they may leave the area, but we're not sure yet."

It is hoped that necropsies can be carried out on the dead whales to find out the exact reason for their strandings and deaths.

"That will at least tell us what it's not for the dead individuals, whether there's any sign of disease, or sickness, or complications," Elizabeth Zwamborn of the Cape Breton Pilot Whale Project told local station I Heart Radio.

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