Bill Carvalho, Founder of Wild Planet Foods, held the live session on 27 April.
A recent Greenpeace ranking of 14 tuna brands in the US placed Wild Planet at the top of the list for sustainable sourcing, and some of the questions submitted focussed on what the less sustainable companies could do to improve.
Mr Carvalho explained that companies receive a low rating when their suppliers fail to prevent habitat degradation or excessive bycatch of non-target species, as well as by taking stock from over-exploited fisheries.
He encouraged these companies to "step up and do the right thing" for the future of the oceans.
He added that whilst there is a short-term cost to make suppliers comply, he believes that consumers are willing to pay for fish caught using more responsible methods.
When asked what consumers can do to make sure they only eat sustainably caught seafood, Mr Cavalho said to look for a specific catch method on the label of the product.
“If it doesn’t say the particular catch method that was used for that fish, it's probably a method that they are not proud of,” he said.
In a restaurant being sure of the sustainability credentials of a product becomes more difficult, but Mr Carvalho said that consumer cards produced by organisations such as Monterrey Bay Seafood Watch are a good place to start.
These cards can explain the most sustainable choice of fish, and taking the cards to a restaurant helps to put pressure on businesses to find out where their stock comes from and make sure it is sourced responsibly.
In another question, Mr Carvalho addressed contamination, saying that there had been concerns about radiation in fish post-Fukushima, but radiation had been below detectable levels in Wild Planet products for the last two years.
He also advised that consumers should follow governmental regulations on a safe level of fish to eat to avoid danger from mercury contamination, particularly in the case of pregnant women or children.
Finally, Mr Carvalho answered a question about slave labour. He said that the recent stories of migrant workers being captured as slaves on fishing boats, after thinking they were heading for a new life, were very concerning for all seafood producers.
However, he said that the problem is thought to be limited to a few operations in South East Asia.
View more of Mr Carvalho's answers in the recording below.
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