Not all streams, rivers, lakes and ponds come stocked with a plethora of fish on their own. This is one of the things that NY State DEC does which is called “fish stocking”.
Fish stocking is when DEC releases over one million pounds of fish into more than 1,200 public streams, rivers, lakes and ponds across the state. (http://www.dec.ny.gov/outdoor/7739.html)
There are two main reasons for doing so. One, to enhance recreational fishing and two, to restore native species where they originally occupied. The fish that are released are found in hatcheries that are run by DEC. There are currently 12 hatcheries that raise anywhere from one kind of fish to multiple fish such as brook trout, rainbow trout, lake trout and walleye to name a few.
Without the assistance of DEC, some ponds, streams, lakes and rivers would be quiet remain inactive because of the lack of fisherman visiting.
For a complete list of fish stocking information in specific waters (by county) check out the link below.