This is a great old Native American fish trapping technique. It’s best used in tidal waters rivers or creeks.
The concept is to funnel finish into an area where it’s hard for them to find the way back out, it’s the same concept behind a minnow trap or soda bottle funnel trap
Drive stakes side by side into the bottom in shallow water to create a square or fenced in area of sorts in the water. Make sure the open end of the funnel is on the downstream side where the water is being forced into the opening. Other materials can be used to construct this trap such as rocks, but this is the most effective and allows for building it in slightly deeper water. One trick is to build it starting at one side of the bank and extending out using trhe side of the bank as a barrier and forcing fish towards your trap
It’s a great and simple trap that allows you to catch the fish by hand or spear them once they are in your trap. You’ll be amazed at how effective this survival fish trap really is, even small ones work pretty well.