Stocked trout don’t have a guaranteed lifespan. Some live a few days, and others live upwards of seven years. Their lifespan depends entirely on the water conditions, fishing pressure, predators, and access to food. They’re raised in controlled environments and released into the wild to acclimate and survive.
Without stocked trout, many of us wouldn’t be passionate trout anglers. Every year, millions of trout are stocked across the United States, offering anglers access to trout in urban ponds and lakes. The easy access to stockers starts a passion that leads anglers to pursue wild and native trout in the country’s far reaches.
Stocked Trout Lifespan
Stocked trout can live up to six or seven years in an ideal world with no predators, perfect water conditions, and ample food. Every normalcy has anomalies and exceptions, but most stocked trout don’t live past the first few weeks.
Stocked Trout Lifespan and Water Conditions
A famous study was completed in 2018 that studied stocked trout behavior in the Southern Appalachian Mountain Streams. The study happened over four years and involved tagged and stocked trout.
The entire goal of the study was to gather information on how stocked trout behave and how well they survive.
The study found that trout have a much better opportunity to survive when placed in water below 65 degrees. Regardless of the water conditions, however, the study found that over 60 percent of stocked trout don’t make it past the first week.
Water conditions play a significant role in how long stocked trout survive.
In my home state of Arizona, the Game and Fish Department stocks trout in Phoenix lakes and rivers throughout the winter, fully expecting the fish to die when the temperatures warm in the spring. However, they survive the winter months and allow Phoenix anglers to land trout in the city.
Trouts must acclimate quickly when introduced into a lake, pond, or stream. They thrive in water conditions below 65 degrees. As the temperatures move over 65, trout go into survival mode. If the temperatures stay consistently over 70 degrees, they’ll only last a week or two before they die.
Most game and fish departments attempt to stock trout in water where they’ll survive for at least a couple of months. It’s an expensive process, so the local game and fish departments at least want a decent return on investment.
Stocked Trout Lifespan and Fishing Pressure
It’s surprising how many anglers follow the local stocking schedules. On stocking days, you’ll find multiple anglers waiting at the lake, pond, or river for the trout to drop into the water.
When game and fish departments stock, they try to track how many fish get caught throughout the year. On average, anglers catch 40 percent of the stocked fish. This rate is known as the “return-to-creel” percentage.
If it’s a heavily fished area, these percentages increase into the 60s and 70s. Trout often feed right after they enter the water, so anglers can catch them almost as soon as they enter.
There are usually high limits on stocked fish. Game and fish departments aren’t overly picky when keeping stocked fish.
Stocked Trout and Predators
In the four-year study, of the 60 percent of trout that died the first week, predators ate 30 percent. Predators are smart. They know where the stocked trout live and how easy of targets they are. Stocked trout aren’t used to having to watch for any predators while in their tanks.
They don’t immediately hide after entering the lake, pond, river, or stream. Birds, larger fish, and other predators take advantage of their vulnerability. If the trout are smart or lucky enough to survive the initial wave of predators, they give themselves a far higher chance of survival.
It takes time for stocked trout to learn what they have to watch out for in their new conditions.
Stocked Trout and Food Access
Food access is one of the final factors determining how long stocked trout live. When the game and fish department stocks a few thousand fish into a local pond, there’s an immediate fight for food. In their tanks, stocked trout only eat pellets. When they enter their new home, their instincts usually take over.
They find insects, crustaceans, worms, and other fish to eat. It may take time, and the fish that don’t know what to eat die fairly quickly. Newly stocked trout eat everything from trash to old lures. They get even more acclimated to their conditions as they learn what is food and what isn’t. They’re more willing to bite your lures if they’re hungry when they hit the water.
Most stocked trout don’t pass the first few weeks in their new conditions. Challenging water conditions, predators, fishing pressure, and a lack of food take out trout daily. As anglers, your best chance of catching stocked trout is in the first few days after they’re stocked when they’re hungry and trying to do anything they can to survive. Trout are a sensitive fish that need a multitude of factors to align for them to survive.