If they keep killing sharks, then the shark population will become extinct, I'm not sure if anyone wants to put a stop to it at all. About 100 million sharks are killed by humans every year.
Deltas are similar to alluvial fans in shape, but are deposited in a different environment. Sediments that form deltas are transported in continuous flowing water. Delta deposits are found at the mouths of streams or rivers as they empty into lakes and oceans also River channels cross delta and alluvial fan deposits. Hope I helped a bit