NORTH BAY -- It's a yearly tradition in North Bay, seeing the shad flies take over the waterfront and downtown.

By the thousands, they cling to walls, lamp posts, signs and even trees.

"I love them," said one woman. "They're a sign of a healthy lake. If you're born and raised in North Bay, you have to accept them."

The smelly bugs are harmless. They're known for their foul odour and fast mating. They have no mouths due to their short lifespan, but that doesn't mean they aren't a nuisance to some, especially anglers.

The bugs are a tasty treat for area fish and with the bugs coming out in the masses, the fish get quite full after eating them.

"It sucks for fishing and it sucks for swimming for a couple of weeks," said another North Bayite. "It is what it is, but I love seeing tourists run away screaming from them."

Shad flies are also known as mayflies. They come out of Lake Nipissing when the water temperature is just right. They usually hang around for a couple of weeks starting every July.

"They're our mascot," said Tourism North Bay Executive director Steve Dreany. "Around the shores we have so much shallow water and because the water is really shallow there, the sun heats it up and it gets a lot warmer than deeper water that has the cooling effect."

They gather in large swarms to escape predators -- and because they are not skilled flyers.

 "When I was a teenager, some friends of mine and I went to the movie theatre and a lot of tourists were there," recounts one man. "They covered me in shad flies and when the tourists came out, I started screaming and the tourists were panicking."

While we have seen shad fly pins and T-shirts for sale in the past, this year, a local band known as the 'J Houston Band' has written and released a new song and music video about the tiny insects called the 'Shad Fly Shuffle.'

"The words were given to Jim from J Houston Band," said bass player Carolyn Houston. "He thought the words were great, so we wanted to write a song and we did a garage recording of it."

Just like Toronto's CN Tower, North Bay has its own tourist attraction, even if they are only a couple of millimetres in size.

"They're always like friends on your shoulder. They're like a little partner or buddy, so it's kind of fun," concludes one shad fly fan.