There are a bunch of world record fish that likely will never be broken.

In some cases records will remain safe due to new regulations. Take for example, Joey “Sturgeon King” Pallotta’s 468-pound white sturgeon that he caught out of Benicia, CA back in July of 1983. Since then, fishing regulations governing sturgeon up and down the West Coast include maximum size limits to ensure the big spawner females don’t get taken out of the gene pool.

In other cases, habitat degradation, development, pollution and over-harvest have all but wiped out the ability of some species to reach record class sizes anymore.

From monster great white sharks to Tuna the size of small cars and brook trout as long as your leg, here’s Field & Stream’s list of 15 (most likely) Unbreakable World Records.