10 Mysterious Mass Animal Deaths


One of the strangest events that happens in nature is when a large group of animals die at once. While many times these group deaths can be attributed to a specific cause, there are a few mass die-offs where there is no clear culprit. The absolutely frightening aspect of these mass deaths is that the Earth’s ecosystem is incredibly delicate. A drop in the population of one animal can have untold and terrifying consequences for the Earth’s ecosystem that could be disastrous for the human race. Here are some mysterious, troubling mass deaths of animal groups.

10. Velvet Swimming Crabs


In January of 2010, 40,000 dead velvet swimming crabs washed up on England’s Thanet Coast. Then, a year later, 25,000 crabs washed up dead on the same shore. Both times, the beach was littered with the dead bodies which attracted a large amount of birds, and it soon became a safety hazard.

At first, researchers thought that the crabs may have been killed by a virus, but after the second year, they believe that the cold weather may be causing the crabs to go into hypothermia. But the only evidence of that is that any time there have been large amounts of dead crabs found, there was snow on the beach and researchers have no definitive answer as to what killed the crabs.

9. Borneo Pygmy Elephants


Borneo pygmy elephants are the smallest breed of elephant in the world and only have a population of about 1,500. Their very low numbers made for an alarming sight when 14 dead elephants were found in the Gunung Rara Forest Reserve in the Malaysian state of Sabah. Tests were done and the only thing that they concluded was that it was an unknown toxin that killed the elephants.

It’s unclear if the animals ate the toxicants by accident, or if they were poisoned. There was an oil palm plantation and logging concessions nearby that viewed the elephants as a nuisance and suspicion quickly fell on them. However, a criminal investigation didn’t turn up any evidence of foul play and the elephants’ deaths remain a mystery.

8. Humboldt Squid

One of the most mysterious creatures in the animal kingdom is the Humboldt squid. They’re six feet long, have strong arms, powerful beaks and they have red skin, which is why they are sometimes called “Red Devils.” The reason the giant squid is so mysterious is because for 95 percent of their lives they live at depths of 660 to 2,300 feet during the day and at about 220 feet at night. These levels are at depths that can’t be reached by scuba divers, so observation expeditions of the creatures are a very costly venture.

Needless to say that when thousands of them washed up on the beaches in California in January of 2005, it troubled and puzzled researchers why they would apparently beach themselves. One researcher says the squids may have become mentally deranged after a combination of eating something toxic and spending too much time in warm water. However, that is just an educated guess and the reason for the beaching remains unknown.

7. Harp Seals


In December of 2010, the residents of northern Labrador, Canada, started to find dead harp seals littering the beach. Over the course of the month, over 200 young and adult seals washed up dead on the sands. After the bodies were found, a biologist with Fisheries and Oceans Canada did some tests on the frozen carcasses, but couldn’t figure out what the cause of death was.

All of them looked to be healthy, the pathology tests didn’t turn up anything and there was no sign of disease in the seals. One theory is that somehow the seals drowned, but he is unsure how a large group of them would have managed to do so.

6. Saiga Antelopes

The saiga antelopes are an endangered animal that is recognizable because of their oversized nose. They are a critically endangered species and in 2014, there were only 257,000 antelopes in four herds. They are only found in parts of Russia and Kazakhstan, and during the winters the herds congregate and then split up during the spring, where they give birth to calves.

In May of 2015, during the calving season, disaster struck and within two weeks, 134,000 saiga, which is half the population, mysteriously dropped dead. It is believed that bacteria is the culprit, but it is unclear how it became so deadly to the saiga because it is very unusual for a bacterium to be harmless one day and then radically devastating the next. Researchers are currently investigating the cause of the mass deaths in the hopes that they may save the rest of the saiga.

5. Sheep

Outside of Istanbul, Turkey, in July 2005, a group of sheep herders left a group of sheep grazing in a field and went for breakfast. When they returned to the herd, they found an incredibly bizarre scene – the sheep were committing suicide.

One sheep had walked off a cliff and fell 50 feet to its death. Amazingly, the rest of the sheep followed the leader and walked over the same cliff. 1,500 sheep ended up jumping while the shepherds watched on, unable to do anything to stop it. In total, 400 died, the others were able to survive because the sheep that had already fallen made a cushion.

4. Pilot Whales


Pilot whales are similar to killer whales because they are both in the dolphin family, but pilot whales are slightly smaller and are almost all black or gray with a lighter spot on their stomach. They are found in both the northern and southern hemispheres in tropical parts of the ocean.

Pilot whales also have an unusual tendency of beaching themselves en masse. For example, in early 2009, over 400 pilot whales died after they beached themselves in Tasmania. Another group beaching happened in February of 2015, when over 100 pilot whales died after swimming ashore in New Zealand. Those are some of the biggest mass beachings, but smaller groups of pilot whales beach themselves frequently all over the world. For example, 33 were found dead on a beach in Ireland in November of 2010. Then, 20 were found on a beach in Florida in November of 2012. Another mass incident happened in Nova Scotia, Canada in August of 2015, where people found 10 beached whales and six died before they could be returned to the water. Those are only a handful of examples and no one is sure why the whales are doing this. It appears that they have a problem navigating in shallow water, but otherwise, scientists are at a loss as to why it happens. Some speculation is that sonar may be affecting them, or it could be disease or trauma that leads them to the shallow water, but no one knows for sure.

3. The Indian River Lagoon, Florida


The Indian River Lagoon is the most biologically diverse estuary in Florida and the area encompasses about 40 percent of Florida’s coast. It is also the home to one of the most mysterious mass animal deaths in American history. The first deaths were discovered in July of 2012, and it was 43 manatees. Over the next couple of months, more dead manatees were found in the area, bringing the total manatee deaths to 111. Between January and June of 2013, 250 to 300 dead pelicans were found. They were all very thin and had heavy parasite loads. Also found in January of 2013, were 46 dead bottlenose dolphins, and like the pelicans, they too looked thin and sickly.

Biologists believe one culprit for the die-offs was a change in the ecosystem. An algae superbloom killed off 60% of the seagrass, which is what manatees eat. However, researchers believe that is one element and are still puzzled as to what the actual smoking gun is.

2. Chile’s Coastal Life


Chile is a long, narrow country that encompasses the Southwest coast of South America. In 2009, it was also the home of a number of mass animal deaths. The first one happened in March, when 1,200 penguins were found dead on a beach in the southern part of the country. A month later, millions of sardines washed up on the shore not far from the penguins. The smell got so bad that schools near the beach had to be closed and the army had to shovel the fish off the beach. Then, over the course of three months, Andean flamingos began abandoning their nests in the northern part of the country. Due to the abandonment, over 2,000 eggs didn’t hatch. Then the final mass die off was in May, when almost dead 60 pelicans were found on a beach in central Chile.

Four major die-offs from four different species was quite troubling for the science community, but there was no consensus as to what caused the deaths. Some of the culprits include global warming, overfishing, disease, and pollution.

1. Worker Bees

The most famous mass die-off of animals is the death of worker bees throughout the world. In the 1990s, beekeepers started documenting higher than average deaths of bees during the winter. In 2006, the deaths were given a new name, Colony Collapse Disorder. By the time the syndrome started making headlines, beekeepers were losing 30-90% of their worker bees over the winter.

This is a really troubling problem because of how important bees are to our ecosystem. Bees and other insects pollinate one-third of everything we eat. Out of all the crops we eat, which includes all fruit, vegetables and nuts, 84% is pollinated by bees. So quite simply, without bees, it could lead to global starvation. While the bees are not near extinction levels yet, an upset in numbers could lead to an imbalance in the world’s ecosystem that could be devastating in unforeseen ways.

There are a number of theories of what exactly is killing the bees, but no one is really sure. A couple of suspects include microbes, malnutrition and fungicide, but the strongest suspect is neonicotinoids, which is a family of pesticides. In fact, in 2013, Europe banned the use of neonicotinoids for two years and the American Federal Drug Administration is currently reviewing its use. However, neonicotinoids are only suspected and researchers are still investigating the possible causes for the deaths of millions of bees around the world.

Robert Grimminck is a Canadian freelance writer. You can friend him on Facebook, follow him on Twitter, follow him on Pinterest, or visit his website.

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  1. No matter what happens, just blame global warming. Being a scientist is the easiest job in the world, because no matter what the disaster is, all they have to say is, “could have something to do with global warming” and no more research is warranted.