Every year, freshwater fishermen sit at their computer screens, refreshing the trout stocking report to see if their local fishing haunts have been stocked with a bounty of rainbow trout, brown trout, brook trout, and a brown/brook hybrid, the tiger trout.
This year, Massachusetts Fisheries and Wildlife stocked those four aforementioned trout species across Massachusetts in huge numbers. In the spring, the state received hundreds of thousands of live trout dumped into various water bodies. This fall, 65,000 fish were added to these ecosystems.
Massachusetts funds its trout stocking program via the sale of annual fishing licenses. The investment by the state into trout stocking is a good one, as, according to Hatchery System Supervisor for Massachusetts Fisheries and Wildlife, Dr. Caleb Slater, “each dollar invested into the trout stocking program returns another $22 to the Massachusetts economy….according to a study commissioned by MassWildLife in 2019.”
The only species of these slimy dollar bills included in the stocking that naturally occurs in Massachusetts is the brook trout, as feeble populations of native, sea-run “salters” still fight for survival.
These trout are being relocated where they otherwise would not have, into places that already have flourishing native fish populations. How do these incumbent fish respond to the “out of towners?” In certain stocked ponds, such as Walden Pond in Concord or Shubael Pond in Barnstable on Cape Cod, non-native, adapted, reproducing fish species, namely smallmouth bass, currently thrive there and reproduce alongside the native species, such as Largemouth Bass and Yellow Perch. Stocked trout, however, are “sterile,”or unable to reproduce.
“The main issue we find when they add the fish is food source,” local angler Benjamin Sussman said, “whether it is the {natural forage}, or the newly stocked food source for the freshwater’s top predators.” This natural forage includes small crustaceans, such as crawfish, and small baitfish such as smelt and killifish, most commonly. Everything in the pond can be forage for something besides adult snapping turtles and the sediment they hide in!
While smaller local fish can find themselves competing with these trout for the existing forage in these water bodies, “the local fish have the upper hand [because] stocked trout are bad at being wild trout, initially,” said fisherman Cory Azmon. “These fish are dropped into an environment where they must fend for themselves instantly, after being cared for and raised in a controlled environment.”
In hatcheries, stocked trout are fed and kept in large tanks until they reach desired stocking size, which for most of these fish is between 12 and 16 inches. Every so often, the Massachusetts Department of Conservation and Recreation will release the breeders, or broodstock, trout into the ponds. These fish are quite large, often exceeding 20 inches!
These broodstock trout are released every few years, most recently in 2020. This allows the state to keep some of its trophy brown trout fisheries healthy, such as its two popular Concord holes, Walden and White, while keeping the gene pool fresh at the hatchery, leading to a healthier, future population of “stockies.”
According to Dr. Slater, “Retired broodstock fish are often stocked into waters known to be able to ‘hold over trout.’ These are deep lakes or ponds that contain enough cold water below the thermocline in the summer for trout to survive.”
To experience the stocked trout waters firsthand, one does not need to leave Boston. Jamaica Pond, among the deep, aforementioned water bodies, in the city’s Jamaica Plain neighborhood, boasts one of the stronger stocked trout fisheries in the state, especially if you are looking to tussle with a fat rainbow.
Jamaica Pond, while its trout fishery remains strong through generous, bi-annual replenishment, has populations of largemouth bass growing to trophy sizes. Stocking trout, for smaller species, can create food competition, as they share a diet. Thankfully, insects make up a good portion of the diet for both and are always plentiful. However, for the largemouth bass, the oily medium-sized trout morsels are a welcomed, calorie-bursting addition.
“There are some major behemoth bass in these stocked trout ponds,” says local angler John Zoetjes. “Jamaica, Walden, those big Cape ponds: all of them have giant bass.” These ponds, however, boast relatively small populations of these bass. When there is a small population of bass, paired with a replenished source of calorie-rich food, it allows these fish the nutrients and physical space to grow to huge sizes.
While largemouth bass themselves may be a beneficiary of the trout stocking program in terms of food source, many native fish have found themselves flopping over ice alongside the trout and ending up on dinner plates in unsustainable numbers.
“These guys sit by the pond with their limit of trout continuing to fish because they can stuff their buckets continually with yellow perch and sunfish,” fisherman Kirk Spinelli said.
“The trout are a sustainable food source, but those panfish need time to reproduce….the trout don’t have to.” This makes trout a much more sustainable food source relative to the native fish.
They make a healthier one, too, as the fish that spend their entire lives in freshwater ponds are prone to high mercury levels. These fish should be released for the health of their species and the fisherman enjoying the sport.
As a result, many ponds that are stocked with trout may appear to have damaged local fish populations due to the new, improving competition from the trout. However, the trout just simply are not skilled enough hunters at first to do so. Holdover trout, which survive in relatively low numbers, will begin to adapt to a wild mindset, taking advantage of natural forage in these ponds and lakes over time.
When examining whether stocked trout are truly damaging local fish populations, one must ask why they receive some of the blame. Since these trout are stocked both for recreation and as a food source, they attract food fishermen to lakes where these trout will coexist with other, often edible, local species. As a result, both get kept, seemingly carrying equal consequences while the trout can be harvested without significant damage to the ecosystem. The same cannot be said for local species, as, unlike the trout, they have the responsibility of providing for the population of its species.
So, no, the trout are not to blame. The issue is one of non-selective harvest, while selective harvest should be adhered to by devoted, avid anglers who care about the health of fish populations going forward.
The stocking program is a great way to get younger people involved in catching, cleaning, and cooking fish. If we, as a people, can use this resource properly, it can remain beneficial to the Massachusetts human and fish communities. By taking food pressure off of local species, we can foster a bright future for our fisher-children and our local fish.
Sources:
Fishermen:
Ben Sussman
Cory Azmon
John Zoetjes
Kirk Spinelli
Expert:
Dr. Caleb Slater, Hatchery System Supervisor, Massachusetts Fisheries and Wildlife
Info on Stocking:
Mass.gov