Every year, hundreds of thousands of trout are stocked in local lakes, rivers and streams. It’s a tremendous undertaking for state trout hatcheries, and it’s funded by money raised through the sale of freshwater fishing licenses. It takes about 18 months to raise a trout to 14 inches in length, and it requires a successful mixture of luck, biology, good timing and hard work.

The Trout Hatchery Process

The whole process begins with the eggs. At the hatchery I visited in Sandwich, MA, the brook, brown and tiger trout are started from eggs and milt collected from the hatchery’s resident fish, but the rainbow trout eggs are brought in from the federal hatchery. The fertilized eggs are placed in shallow mesh pans, which are then submerged in a vat beneath several inches of water. A deep well beneath the hatchery provides a steady stream of cold, crystal-clear water that trickles down over the fragile eggs. The deep well provides water that is exactly 50 degrees, the ideal temperature for hatching trout. Within a few weeks, the eggs will hatch and the trout will begin the cycle of life.

Once they are fully developed into fingerlings, they get transferred into 500-gallon indoor tubs where they reside for several months and grow quickly.

By the time they are around 4 inches long, they are ready for the outside world and are transported to the outdoor pools.

These concrete enclosures, shrouded in heavy protective netting, are their home for the next year. The long, shallow pens receive a steady douse of the cold, clear well water, which flows constantly, keeping the pens clean and well oxygenated. At this point, the trout, residing in a safe river-like habitat, put on the feed bag and daily meals fatten them up quickly. Because the water temperature is constantly around 50 degrees, our long, cold winters don’t slow their growth.

The Trout Stocking Process

The hatchery is set up to run like a well-oiled machine. As soon as the adults are stocked, both in the spring and the fall, their space is replenished with younger fish. The hatchery staggers the hatchlings throughout the year in order to best maximize the space available. After 18 months, most of the fish will be 14-plus inches and ready to hit the local lakes and rivers. A small percentage remains at the hatchery for another year or more in order to provide eggs and milt for the next generation.

These big broodstock trout will eventually get stocked as well, giving anglers a shot at a trophy 3-plus-pounder. An even smaller percentage of fish will be kept to grow to massive proportions. This particular hatchery is open to the public and has a display pool for their most-prized specimens. It is a torturous sight for a fanatical fisherman. For just 25 cents, you can buy a fistful of trout pellets, served up out of a modified gumball machine. Toss them in the water, and witness as 5-plus-pound trout explode on the surface.

Trout do not thrive in warm water, so the adult fish are stocked in the spring and in the fall, with the spring stocking usually offering the biggest bonanza. Depending on where you live, the spring stocking usually occurs from mid-March through April. Many places will be stocked more than once with rainbow, brook, brown, and tiger trout, offering anglers an exciting mix of possibilities.

The first delivery of trout to the local ponds is always a source of much excitement. Like hearing the first peeper or red-wing blackbird of the year, it is a true and much-welcomed sign of spring, and reason to rejoice.