Dead fish washing up on Bradford Beach by the thousands: What are they, and what's causing this?

MILWAUKEE (WITI) -- Dead fish are washing up on Bradford Beach by the thousands! So what's causing it?

FOX6 News spoke with Baylee and Brooklyn Bates. They're sisters, and they were amazed by the amount of dead fish on Bradford Beach on Tuesday afternoon, June 24th.

So what, exactly is happening here?

FOX6 News spoke with John Janssen at the UW-Milwaukee School of Freshwater Sciences.

He says the fish are "alewives" -- coming to shore to spawn.

Janssen says the fish are dying because they are starving.

Mussels in Lake Michigan are apparently stealing food in the food chain.

Janssen says a big temperature drop can trigger these massive "die-offs."

"This is a saltwater fish, and they have difficulty living in fresh water.  It just weakens them a bit," Janssen said.

Janssen says we've seen this before, but this die-off is occurring a little later than we're used to.

Lake Michigan is warming up slowly this year.

Meanwhile, the seagulls are fat and happy. When they see dead fish, it's like a buffet for them!