Skipper personal choice is the normal reason for the colour of any fishing boat.
There were many hundred Danish style anchor seiners that worked out of Hull and Grumsby from the late 1940's up to the 1990's and these were usually painted light blue , the main reason was that the colour was thought to help keep the inside of the boat cool.
The Emma Louise is a vivier crab boat , she keeps her crabs alive by keeping them in a tank of sea water ( constantly being refreshed with water being pumped through from the sea ) so the white colour will be to keep the working deck cool in the summer.
When you cover in a fishing boat like this one then in the summer the working deck can get very very hot so painting the shelterdeck white is very common and is done to help keep the boat as cool as possible
^^ (c) Martin Johns and is hosted on www.trawlerphotos.co.uk
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