Queensland's National Parks Service says two whales washed up on the state's central coast in recent days appear to have died from natural causes

A 17-metre sperm whale was found on Curtis Island and a three-metre pygmy or dwarf whale was stranded on Great Keppel Island.

NPS acting manager Graham Hemson says the deaths are not a concern.

"The sperm whale is a large adult sperm whale - it's almost 17 metres so it's quite possible it's died of natural causes, of old age essentially," he said.

"Nevertheless we can't really investigate it any further because of the advanced state of decomposition of the corpse."

Tests will be run on the smaller corpse to determine the cause of death and to confirm whether it was a pygmy or dwarf sperm whale.

Mr Hemson says there is no link between the two deaths.

"In this case I think the larger whale probably died sometime before it was washed up whereas the smaller whale seems to have beached itself while still alive and died shortly there after," he said.

"I think they're unrelated and in fact the smaller species do have a bit of a track record of beaching themselves."