Harsher penalties for SA shipwreck crooks

People found guilty of illegally pinching or keeping parts of historic South Australian shipwrecks will soon face harsher penalties.

The state government says the top penalty for nabbing or hoarding an unregistered shipwreck relic will quadruple from $5000 to $20,000 from May.

The increase is part of amendments to the Historic Shipwrecks Act, which currently protects 270 shipwrecks older than 75 years in SA.

The changes also include a new $750 fine for lesser offences, more powers for shipwreck inspectors and a streamlined process for shipwreck declaration.

Environment Minister Ian Hunter says there have been a large number of reports of illegal activity around SA shipwrecks and the government is determined to see them better protected.

He said the 135-year-old Zanoni, in the Yorke Peninsula marine park sanctuary zone, a complete 19th century merchant vessel shipwreck, has been among the victims.

"These South Australian assets hold important educational, recreational and tourism value," he said in a statement on Thursday.