‘Ordinarily at this point I’d be looking at her,’ Will Mitchell told me as we approached the Cefas Endeavour, a research ship owned by the Centre for Environment, Fisheries and Acquaculture Science, a mile offshore the Cornish port of Fowey. ‘I’d be looking at the size of her, how she moves, where we’re going to board her. But I’ve worked this vessel before.’ It was a Wednesday lunchtime in July and the sky was overcast – a rare interruption in a week of fine sunshine – but the sea was almost flat.