More than 17,000 fish killed in WA

An estimated 17,500 fish have died in what is understood to be a naturally occurring fish kill in Western Australia's far north.

The discovery of the dead fish on beaches in WA's Kimberley region has been linked to a culmination of environmental factors.

More than 37 species of fish were found on beaches near Broome and locals have uploaded photographs of dead turtles and a sea snake to social media.

A Department of Fisheries spokesman told AAP the fish kill had affected mainly small fish, with less than three per cent recorded at more than 30cm long.

Dead marine species have been found along a 60km stretch of coastline between Willie Creek and Cape Bertholet, but the Department of Fisheries believes the deaths have passed, with no fresh discoveries on Sunday.

Higher than normal water temperatures coupled with warm weather and sustained onshore winds have been floated by the department as contributing factors, with experts predicting it was contained to a localised area before the fish carcases were spread by strong tides.

The fish kill affected predominantly near-shore species including leatherjacket, Spanish flag and northwest snapper.

Fish and water samples have been sent to the department's fish health unit and specialist interstate laboratories for testing, with results expected in coming weeks.