Go see the Comodore at the yacht club and give them the what for !!!
Rule 26 - Fishing vessels
Please note: The following information has been reproduced from Part C (Lights and Shapes) of the Prevention of Collision at Sea Regulations 1983 (external link). The purpose of the reproduction is to explain "graphically'' the requirements of navigation lights on a variety of vessels.
A vessel engaged in fishing, whether underway or at anchor, shall exhibit only the lights and shapes prescribed in this Rule.
A vessel when engaged in trawling, by which is meant the dragging through the water of a dredge net or other apparatus used as a fishing appliance, shall exhibit:
two all-round lights in a vertical line, the upper being green and the lower white, or a shape consisting of two cones with their apexes together in a vertical line one above the other; a masthead light abaft and higher than the all-round green light; a vessel of less than 50 metres in length shall not be obliged to exhibit such a light but may do so when making way through the water, in addition to the lights prescribed in this paragraph, sidelights and a sternlight.