Volunteers are continuing to work along a three and half kilometre section of P.E.I.'s North River near Springvale, cleaning up after 2014's first fish kill.

Over the weekend about 1,000 dead brook trout, rainbow trout, and Atlantic salmon were pulled from the river. It's the fourth year in a row an Island river has been hit with a fish kill.

"To see a large number of dead fish in a stream is very discouraging," said provincial wildlife biologist Rosie MacFarlane.

"I had hoped going into this year that we wouldn't see one, we'd have a break from the last three years of fish kills."

Last year's fish kills were in July, in western P.E.I.

Jordan Condon, a volunteer with the West River Watershed Group, is disappointed to see a fish kill in the Charlottetown area.

"It's not a sight you want to see," said Condon.

"It takes a while for them to bounce back, and I'm a fisherman too and I do fish this river."

Environmental officials have collected water and fish samples to determine what caused this fish kill. MacFarlane suspects heavy rain earlier in the week played a role. It's too early to say for sure, but she said runoff from agricultural land is usually found to be connected to large fish kills.

It will likely take weeks to determine for certain who or what is to blame.