Here in newcastle county down there is a fish trap similar to the one mentioned earlier. Its more curved and I would think that the walls where much higher than they are now. I have wanted for a long time to try making a trap in a river estuary with a bundle of straight sticks. you would push the sticks into the sand at obout 2" to 3" apart in a v pointing down stream and mabey 30 ft wide ( a lot of sticks) the fish swimming upstream would pass the trap in deep water and would be caught when the water level dropped as they returned down stream. I would think these traps would be illegal as are the outterboards and some of the other methods mentioned earlier. My grandfather used an otterboard many years ago it was a very popular method in ireland before it became outlawed.
Does no harm to know for a survival situation though.
Does no harm to know for a survival situation though.