Chinese fishing nets

One of the ways to catch fish is to use a small hand-held net and scoop up fish in it. Well...
... if this works on a small scale, then why not magnify the process and produce a 40 foot square net and scoop up a few more fish? This whole contraption is on a large cantilever, and is lowered and raised into and out-of the water to catch a depressingly meager number of small fish. The nets are beautiful though.