Conservationists have raised concerns about the environmental history of a Canadian company slated to take over Tasmanian aquaculture giant Tassal.

Tassal, the only remaining Australian-owned major salmon farm business, on Tuesday recommended shareholders accept a $1.1 billion takeover bid by aquaculture company Cooke. 

Tassal chief executive Mark Ryan said Cooke was a “natural fit” and the acquisition would fast-track Tassal’s goal to be one of the world’s most transparent and sustainable protein producers.

The Bob Brown Foundation, state Greens and Tasmanian Alliance for Marine Protection (TAMP) have lashed the takeover.

TAMP acting co-chair Sheenagh Neill described Cooke’s environmental history as “chequered”.

In a legal settlement with the Washington Department of Ecology in 2019, the company paid a $US332,000 penalty after the collapse of a pen released 250,000 non-native fish.

In 2019 it was also fined by the Maine Department of Environmental Protection over multiple violations at farming sites in the US state, including having too many fish in pens.

“The purchase of Tassal by Canadian seafood giant Cooke is another tragedy for Tasmania’s environment, and ultimately for Tassal’s workers,” state Greens MP Rosalie Woodruff said.

“Our precious waters are already suffering from the unbridled growth of the fin-fish industry.”

The takeover bid comes after New Zealand company Sealord bought Petuna in 2020 and Brazilian-owned JBS bought Huon Aquaculture in 2021.

Tasmanian Premier Jeremy Rockliff said the state Liberal government was a strong backer of the salmon industry, but was also vigorous to ensure community expectations were met.

“This is an important industry for Tasmania. The salmon industry employs many thousands of Tasmanians in rural and regional (areas),” Mr Rockliff told reporters.

“What is important (is) that whoever invests in our aquaculture … that they recognise we have some of the most stringent environmental regulations and sustainability expectations of anywhere in the world.” 

Tassal’s salmon farms in Tasmania span five marine zones.

“We understand completely that the Tasmanian fish farming industry is Australia’s most valuable seafood production sector,” Cooke chief executive Glenn Cooke said.

“Our top priority will be to work with other producers and government regulators on continuous environmental improvement plans, as well as strengthening supply chain and local community relationships.

“We intend to make strategic investments in engineering, science and technology to further enhance Tassal’s capabilities.” 

The takeover, which is subject to the approval of Tassal shareholders as well as court approval, is expected to be finalised this year.

A 10-year salmon plan being developed by the Tasmanian government for implementation in 2023 includes a shift to land-based and deep-water fish farming. 

By Ethan James in Hobart

Get the latest news, sport, entertainment, lifestyle, competitions and more delivered straight to your inbox with the Canberra Daily Daily Newsletter. Sign up here.