The images below are taken from the Encyclopedia of Diderot, a 32 volume work, assembled by over 140 contributors between 1751 and 1777. It was meant to be a broad summation of existing knowledge and was composed of 70,000 articles and hundreds of engravings covering commerce, agriculture, domestic activities, the arts etc. We can be thankful for the articles and illustrations because a lot of contemporary writing of the time did not cover such subjects as the construction of a working fishermans nets, for instance. These topics were deemed to be too mundane to be dealt with.
In this post I have three examples of tidal fish traps. All three of these are fixed in place and depend on the receding tide to leave fish behind, captured in the different obstructions the fishermen have created. The beauty of tidal fish traps is that they are very low maintenance once they are constructed, particularly if stone is used in their construction. You simply need to check them after the tide has gone out, and pick up your catch.
Siting them requires familiarity with the way the currents run as the tide moves out. Selecting a bay sheltered from prevailing winds means that your structure is less likely to be prone to storm damage. And finding a stretch of shore that is habitually used by feeding fish, whether due to structure, vegetation or the effects of currents is important.
Let’s take a look at three tidal fish traps I have selected for this post.
This trap takes advantage of a slightly sloping beach to increase the funnel effect. It uses natural materials that are almost everywhere close at hand. The same principles could be used if you had rebar and netting available. Or loose rubble to form the wings.
Two styles and construction methods, but the same baffle and funnel combination. The long straight section channels the fish to the open mouth of the trap and the inward curving walls directs them away from the opening. The fish trap on the left in the picture is constructed of vertical supports and pliable branches of vines woven together.
You can just make out the outlet openings low on the horizontal walls, on the water side of the trap. They could have gratings in them to prevent fish from escaping. Obviously this tidal trap could stand the pounding of waves or a storm surge. Of particular note is how this trap takes advantage of natural features of the landscape. Blocking off the relatively narrow opening between the two rock outcroppings takes advantage of the much wider expanse of seaside shore line potentially occupied by fish at high tide.
So a couple of takeaways from the images above. The range of materials that can be used for constructing this type of fish trap are wide ranging. These are just a few examples. Think of the various kinds of fencing material that could be used. Everything from chain link, to poultry, to the various sizes of mesh could work, depending on fish species targeted. Uprights could be posts, rebar, piping etc. Walls could be loose stone, any of the various types of blocks, logs, or even plastic piping secured between uprights.
Familiarity with the specific section of coastline is important. Water flow paths during tides, species available for harvest, and seasonal changes in fish behaviour etc. all will affect your potential catch.