He has previously boasted that when he sits down with his friends Sime "Sam" Sarin, Mario Valcic and Joe Puglisi, they are worth more than a billion dollars between them.
[10] Stehr's business interests are represented in the South Australian parliament by political lobbyists and former politicians, Graham Ingerson[11][12] and Nick Bolkus.
[17] In 2014, Stehr participated in a trade delegation to China with Australia's Prime Minister, Tony Abbott as an ambassador for the seafood industry.
The tank's waters were climatically controlled to simulate the experience of wild fish traversing long distances and varied oceanic conditions.
[5] In Bangkok, 2008 Hagen was presented with the Friend of the Sea, Sustainable Seafood Award in acknowledgement of being the first organisation in the world to create an artificial breeding regime for the Southern bluefin tuna.
[22] In developing this technology, Stehr established the first formal collaboration agreement between Kindai University of Japan and Australia for the propagation of tuna.
Stehr's daughter, Yasmin, spoke representing the 2015 applicant, Oceanic Victor, at a meeting of the Development Assessment Commission (DAC).
[29] Stehr was the seed funder of a sculpture of a "tuna poler" fisherman made by Ken Martin that was unveiled in Port Lincoln in July 2019.
[31] Stehr has stated that his tuna business is "beholden to Japan" and has welcomed the prospect of a Free Trade Agreement with China and reduced tariffs.
In June 2008 Stehr attended a protest opposing Centrex Metals plan to export iron ore from Port Lincoln.
The following year, Stehr voiced his opposition, stating that he was concerned about the new activity harming the town's reputation for producing clean, fresh seafood.
He believes that the establishment of 'no take' sanctuary zones on 1 October 2014 will significantly affect the industry's output and could force Australia to import more seafood.