Pret a Manger has taken the decision to switch to a sustainable type of tuna after the founder watched a documentary about intensive fishing methods. They will start using skipjack tuna later this year which is more common than the yellowfin and bluefin tuna that they currently use. As well as being more common skipjack tuna is caught using smaller fishing boats using a pole and line approach rather than an intensive fishing method which often leads to other sea creatures being caught in the nets. Although the pole and line technique is more labour intensive and therefore most expensive Pret have promised that the increased cost will not be passed onto the customer. Waitrose and Marks & Spencer have also stopped selling bluefin tuna, swordfish and skate and Tesco does not sell bluefin tuna.