Wasaga Beach on the Georgian Bay of Lake Huron in Ontario is recognized as the longest freshwater beach in the world. Today it’s also known as the place where hundreds of dead eels from Southeast Asia mysteriously washed ashore. How did these creatures get from Thailand to Canada and what does their appearance mean?
The dead eels began washing ashore near the mouth of the Nottawasaga River in early September 2015. Their pointed noses and spotted tails didn’t look like anything that normally swims in Lake Huron or any of the other Great Lakes, so samples were sent to the Ministry of Natural Resources and Forestry (MNRF), which determined that they were peacock eels (Macrognathus siamensis), also known as the Siamese Spiny Eel or Peacock Spiny Eel. Peacock eels have never been reported before in any of the Great Lakes.
As the scientific name suggests, they’re native to Thailand (Siam) and are also found in rivers and streams in India, Sri Lanka, Sumatra and Malaysia. In their home waters, peacock eels are bottom feeders that can grow up to 40 centimeters (15 inches) long on a diet that consists of any fish that fits in their mouth. That’s just one of the things that worries Great Lakes wildlife experts.
First things first. How did the peacock eels get to Lake Huron? Being a popular aquarium fish, they were most likely dumped by a careless fish tank owner. However, that doesn’t explain why there were hundreds of peacock eels in the Nottawasaga River and Georgian Bay. This sounds more like the work of an unscrupulous breeder or importer.
Then there’s the question of what killed the eels. Being a tropical species, experts don’t believe they could survive a winter in Lake Huron, but the waters are still warm. Was it something they ate? Was there something wrong with them? Will what killed them affect other fish in the area? Will it spread to the other Great Lakes? What if the experts are wrong and some manage to survive the winter? How will this impact local fish?
That's a lot to worry about. The Great Lakes are the largest group of freshwater lakes on Earth. It would be tragic if they were destroyed by someone whose peacock eel got too big for their tank.