Dolphins are dying in the Port River because of speeding boats and jet skis.
The Transport Minister's being urged by South Australians to impose a speed limit with almost 12,000 supporters signing a petition.
It all started with the Messenger Community News but it's believed Minister Stephan Knoll has refused to put plans in place to slow down boaties.
The Protect Our Dolphins campaign are calling for a 10 knot maximum speed limit in the Adelaide Dolphin Sanctuary but the Minister says the speed limit would harm the working port.
It may now be over to Premier Steven Marshall to see if he will step in.
The Port River dolphins are the World's only Wild Tail-Walkers.
An SA Museum report shows over the past 13 years, 17 out of 35 dolphins have died in the sanctuary and already this year three calves have been killed.
To sign the petition head here