Let's also keep in mind this is a fish which has lived it's entire life in a (freshwater) hatchery. It's survival has little or nothing to do with returning to the ocean as it has already lived its life entirely in freshwater.
Broodstock salmon can and do hold over in any pond with deep enough water to enable trout to hold over. Take a look at the depth chart of jamaica pond and you will see it is plenty deep enough for this. In fact, due to its urban setting, and byzantine regulations regarding wading and boating access, fishing pressure is fairly light and a lot of fish hold over year to year. Many people have chosen jamaica pond as spot to try to catch a "pin" trout or salmon.
On the plus side, as I see it, Massachusetts does not charge you an additional fee to catch fish paid for with federal money.
Personally, I don't see the NH broodstock program as much better. Additional fees aside, the sections of the Merrimack where they are stocked bear little resemblance to the type of water where you would catch atlantic salmon in the wild. Most of the fish that attempt to move downriver end up dying in the canals of Lowell. Any fish exeptional enough to make it to sea and return to spawn will find their passage blocked by the dam in Lawrence.
I've got as many gripes with the state of Massachusetts as anyone, heck I'm a libertarian, but we're talking about fish stocking here. Lets keep things on topic.