A rare species of poisonous puffer fish was discovered on Vancouver Island earlier this month.

It's the first time that a spotted porcupine puffer fish has been seen in British Columbia. The tropical fish, normally found in waters near California, washed up in Jordan River on Oct. 5th.

Since then scientists have been trying to figure out how it got so far north.

"Finding a puffer this far north is exciting but also quite odd," said Jim Powell, CEO of the B.C Center for Aquatic Health Sciences. 

Mystery surrounds the small fish's travels north. The species is not known for being strong swimmers, which would make it difficult for them to go against the current. 

"They're such a wee little fish," said Powell. "If you've ever seen them try and swim they aren’t the fastest, they certainty are not Olympians." 

The curator of vertebrate zoology for the Royal BC Museum, Dr. Gavin Hanke, said he doesn't believe the fish was a pet. 

"I don’t normally see that species in the pet trade," said Hanke. "It could have come up on some fishing gear, or it could have come offshore in the warmer water in the warm blob that we've seen the last few years." 

That blob is also responsible for bringing other tropical species north. Last month, an olive ridley sea turtle was rescued in Port Alberni, one that veterinarians say likely got caught in the warm waters of the blob. 

Although the spotted porcupine pufferfish isn't hurting native B.C. species, other invasive species that show up have the potential to. 

"They might be really harmful for local species," said Dr. Martin Haulena, the head veterinarian for the Vancouver Aquarium Marine Science Centre.

"Native species might be introduced to animals and diseases that they wouldn’t otherwise be exposed to."

Scientists say the warm waters of the blob and El Niño years typically bring more tropical species to B.C waters. However, these recent visitors are anomalies.