This Cambodian shows us how to catch fish in a river using naturally occurring resources. He uses what look like bamboo shoots and runners (twigs with vines or grasses would probably work, too) to construct a fish trap which allows entrance but no exit.
He shows us every step of the process, including nonchalantly removing a leech from his ankle, and makes a very respectable catch for just twenty minutes effort (the video is speeded up) and a six-hour wait.
The U.S. Army manual features worthing very similar. Have you ever caught fish with a type of trap? If you have please post a story or photo in the Comments section or email it to me at news(@)selfreliancecentral.com – but without the parentheses.