Far inland from the Gulf of Maine, deep in the hills and mountains of New England and the Maritimes, lives the brook trout. A highly desired sport fish for generations of freshwater anglers, to many the brook trout is a symbol of true wilderness, found only in pure cold waters unpolluted by human activities.

Known by many names (squaretail, speckled trout, or brookie), brook trout (Salvelinus fontinalis) is the honored prey of anglers throughout New England and the Maritimes. Native to the Northeast's waters, its status among freshwater anglers in New Hampshire made it the official "State Freshwater Fish." Part of the attraction might be the beauty of the fish itself and the stunning sites in which the fish is found.

Brook trout are iridescent blue or green in color, and speckled with yellow spots on their sides. Their backs may be olive green with dark wavy lines. Unlike brown trout, its teeth are only in the front of its mouth. Brook trout are found in mountain streams, rivers, lakes, and ponds. Part of the salmon family, brook trout require a year-round supply of cold, well-oxygenated water and sufficient sources of food to live. It will not thrive in water bodies where the temperature rises above 68 degrees F (20 degrees C)in the summer months. Furthermore, the fish requires gravel beds in which to spawn.

Brook trout generally spawn in the late fall. As the water turns colder the female will begin to scoop out a shallow hole in which to lay her eggs. The male and female will simultaneously extrude eggs and milt into the hole. The female then sweeps gravel onto the hole, covering the fertilized eggs. The eggs develop through the winter, hatching in two to three months. First known as fry, later as fingerlings, juvenile trout eat plankton, then switch to insects as they grow larger. They generally remain in the pond or stream in which they were born, although some brook trout may actually head out to sea to live part of their lives, returning to freshwater to spawn.

Brook trout like to eat. Anglers use fancy flies to trick a hungry brook trout into thinking the lure is a tasty insect fluttering on or in a cool stream or lake. Late spring and early fall are the best times for trout fishing in New England, when the waters are cool and the insects are numerous. Many northern bodies of water are fed by deep springs, whose constant stream of cold water helps keep the lake or river temperature down during the hot summer months.

Though fishing stories tell of huge 10-pound (4.5 kg) fish caught in the deep woods in New Hampshire and Maine, today's brook trout average from 1 to 4 pounds (.5 to 1.8 kg). In Canada the trout may run from 4 to 7 pounds (1.8 to 3.2 kg) in certain remote regions. The record for the largest brook trout ever caught was in Ontario in 1916 — the fish weighed 14 pounds, 8 ounces (6.5 kg), and was 31 inches (79 cm) long!

Because brook trout are so desired by anglers, state and provincial governments are eager to grow the fish in hatcheries for release into the wild. The trick to raising trout in a hatchery is providing a steady stream of cold, oxygen-enriched water to the growing fish. Nature does it well; fishery managers rely on machines to do it for them. At a hatchery, eggs and milt are taken from wild trout and fertilized. The resulting fry are provided a constant source of food. When the fry are able to eat insects, they are moved outdoors to a series of tanks to grow into juveniles. By restocking the many cold-water lakes and streams in the Gulf of Maine watershed, brook trout continue to be the highlight of many an angler's season.

While stocking helps meet the demands of anglers, native brook trout still reproduce naturally, living wild and free in many of the rivers, lakes, and ponds of the Gulf of Maine watershed.