Angler's Question:
Why Does Maine Stock Game Fish?

By Peter Bourque

We receive lots of questions regarding fish stocking in Maine. Why do we stock? Why don't we stock more? What species do we stock and why? Why do we stock varying sizes and ages of fish? In the next few paragraphs I will attempt to answer some of these questions.

Maine stocks about one and one quarter million fish each year. Most of these fish are six inches or larger when released into the wild. All of the Maine Department of Inland Fisheries & Wildlife's fish culture or hatchery program consists of growing various species of trout and landlocked salmon. At the current time we are raising brook trout, brown trout, lake trout (togue), landlocked salmon, splake (a brook trout/lake trout hybrid) and rainbow trout.

We stock fish to provide fishing opportunities for anglers that would not otherwise be available. Each of the state's nearly 6000 lakes and ponds and almost 32,000 miles of rivers and streams present some type of angling opportunity as well as management challenges.

Click Here To Subscribe!

Historically, fish stocking 50 to 100 years ago was done with little knowledge of the habitat requirements for a given species or the dynamics of a particular ecosystem. In the early 1950's fishery managers began to study these ecosystems to gain an understanding of how they operated in order to make informed decisions for future management of these waters. As more information was gathered, management recommendations resulted in a variety of stocking changes. In many situations the species to be stocked was changed. Perhaps many didn't realize that at one time Maine stocked four species of Pacific salmon. In other instances changes were made in the size of fish stocked. Years ago millions of tiny fry were planted in waters with large populations of predatory fish, resulting in few returns to the angler. In addition, many stockings especially in brooks and streams were stopped completely as there were adequate populations of wild trout.

IFW's fish stocking programs actually fall into four categories: introductory stocking, maintenance stocking, experimental stocking and put and take stocking. Introductory, maintenance and experimental stockings would all fall into the category of "biological" stocking programs. In each of these the habitat, water quality and available forage would be assessed and considered to be suitable to allow a stocked fish to survive and grow to legal size. Of these three types of programs the introductory one is the smallest. In this program we would consider all conditions to be suitable including sufficient spawning area for the species being stocked. Generally, after a few years, stocking can be discontinued and the fishery will maintain itself through natural reproduction. In fact, in a few of our brook trout waters we have established self- sustaining populations with a single stocking.

The largest part of Maine's stocking is considered a maintenance stocking program where routine, continuous stocking (on various time tables) may be made to supplement an insufficient amount of natural reproduction or substitute where there is a complete lack of natural reproduction. The lack of natural reproduction is generally a result of no suitable spawning habitat. We often get the question: Do stocked fish spawn? Yes, indeed they would spawn very nicely assuming there was suitable habitat conditions for successful spawning. Since many of Maine's waters have great habitat for growth and survival of stocked fish, but lack spawning area, our maintenance stocking program must continue.

The last of our three biological stocking programs is experimental. Experimental stocking is used in special situations to help us predict the success of a new program where complex biological interactions exist. Fish may be stocked on an experimental basis, and once information is gathered, the program may be changed, continued or stopped, depending on the results of the stocking. Past and present examples of our experimental programs include stocking of brown trout in tidal rivers such as the Mousam and Ogunquit, while currently we are conducting an experimental stocking with rainbow trout in several waters in central and southern Maine.

Our one non-biological program is called "put and take" stocking and consists of stocking legal-sized fish into waters where they are expected to be caught within a short time. These waters generally do not provide the right conditions to hold trout over the entire year (for example, the water may be too warm in the summer, or too low) or there may be very heavy fishing, such as waters near larger urban areas.

This stocking provides a short-term fishery that must be maintained by continuous stocking during periods when the habitat conditions are suitable. Most of this program is conducted in high population areas where other opportunities for trout fishing may not exist, i.e. spring stocking of some of the brooks in York and Cumberland Counties. Since hatchery space is limited, the stocking of large numbers of legal-sized fish is also limited. In a few years, as a result of the seven million dollar bond issue, we will be able to increase the number of "put and take" trout. In addition, a program such as this would not be considered where there are adequate numbers of wild fish.

All "biological" stocking programs are done with considerable thought and information available to each regional fishery staff. Many years ago department fisheries biologists established a set of guidelines for stocking. These guidelines include recommendations on species to be stocked, size of fish at stocking and numbers to be stocked. Species, size and numbers are based on the available habitat for the species to be stocked and the amount of competition from other fish species and the available forage (feed).

In order to give our biological stocking programs the best chance of success, fish quality goals (size and condition of fish at a particular age) are established for all species and strains grown in our hatchery system. Department fish culturists strive to meet these goals in order to provide for better survival following stocking and greater returns to the anglers. They take great pride in the products they stock and are continually finding ways to improve them.

IFW has nine hatcheries and rearing stations. Hatcheries are just that, where fish are hatched and also raised. A rearing station is where some fish are moved to after hatching. Each of these nine facilities represent sites which have proven to be conducive to the production of a certain species of coldwater fish. Some of them are fed by lake water, while others receive their water supplies from springs and underground wells.

Fish production schedules are planned several years in advance to assure the number and size of a particular species or strain are available to meet the needs of anglers. Exactly what species are produced by a particular facility are governed by the need for specific species, strain and size of the fish, the suitability of a facility for certain species and the geographic need for a specific species.

Another "special" program is the stocking of many of our larger, "retired" hatchery brood stock. These give anglers the opportunity to catch a trophy size fish. Brown trout measure out from 26-28 inches, togue are 26-28 inches, and the brook trout released are up to 22 inches in size. The brood stock are the fathers and mothers that produce the fingerlings, fry and yearlings the Department of Inland Fisheries and Wildlife stock throughout the year. The biological clock has stopped ticking for these fish, they are no longer active in their reproduction cycle, so they are released into the wild. Fish range in age from three to twelve years. A list of stocked fish is available through our department or on our website.

And of course, you may wonder just how they do get into those 700 lakes, rivers, streams and ponds? There isn't one process used for all them. It depends on the geographic location of the water body, and its accessibility. Some are stocked by running a hose from a hatchery truck to the water and some are moved to ponds by a bucket that is filled at the truck. We use airplanes to bring fish to remote ponds where travel by truck is not feasible, and in some areas, we backpack them in as fry in a specially made pack frame designed to carry very small fish. The stocking of many waters also includes the boating of fish to various sections of a water body to spread the fish out and reduce attacks on them by predators such as larger fish or birds.

Hopefully this has given you an overview of IFW's stocking programs. If you are looking for a list of what bodies of water we stock, give us a call at 287-8000, or by check us out online at

Peter Bourque is Director of Fisheries Program Development for the Maine Department of Inland fisheries and Wildlife

Click Here For Past Feature Stories!!

Feature Story |  Current News |  Photo Gallery |  Advertising |  Subscribe Today |  Outdoor Resources |  Home