Traditional boat designs are strikingly local, changing from one bay to the next along the same coastline. Each type is a solution to the particular conditions where it was built.
The launching ground shapes the hull
A boat that must be dragged up a shingle beach every night needs a different underside from one that lies afloat in a sheltered harbour.
Beach-launched types tend towards flat or lightly curved bottoms, sturdy keel bands and a weight that a handful of people can move. Everything else is subordinate to that requirement.
Where a deep-water quay existed, builders were free to design for sailing performance instead, producing finer hulls that would be ruined by regular grounding.
Sea state at the harbour mouth matters more than the open sea
The dangerous part of a working day is usually the entrance, where swell meets shallow water and a boat must be handled with no room to manoeuvre.
Bays with a bar across the mouth produced high-bowed types built to lift over broken water. Sheltered inlets produced lower, drier boats that would be swamped elsewhere.
Because that entrance condition changes over short distances, so does the boat, which is how neighbouring villages ended up with visibly different fleets.
Available timber sets the construction method
Builders used what grew nearby. Where long straight timber was available, planking ran full length; where it was not, hulls were built from shorter overlapping pieces.
Naturally curved branches were prized for frames because a grown curve is stronger than a sawn one, and finding them shaped how a yard sourced material.
Once a method was established it persisted, since the tools, the moulds and the apprentices were all specific to that way of working.
The fishery dictated the working deck
A boat setting pots needs clear space along one side and somewhere to stack gear. A boat working nets needs a different arrangement entirely.
Those requirements determined where the mast sat, how the thwarts were placed and how much freeboard was needed, all of which are visible in the finished shape.
Change the target species and the boat changes with it, which is why a type can be dated by the fishery it was built to serve.
Why the types survive without the work
Almost none of these boats are commercially viable now, having been displaced by fibreglass hulls and engines that make local optimisation largely irrelevant.
They survive through restoration groups, harbour trusts and racing classes that maintain a handful of examples and, more importantly, the skills to repair them.
A visitor who wants to see the real thing should look for a working yard rather than a museum, because the knowledge lives in the people still cutting timber to a local pattern.