Wild Georgia: Trout in a stream means good water quality

Later this month, state and federal fisheries workers will begin stocking dozens of “trout streams” in North Georgia’s mountains with hundreds of thousands of young trout raised in hatcheries.

About the same time, multitudes of anglers will begin descending on the streams for the thrill and satisfaction of catching one of the elusive fish — perhaps a beautiful rainbow trout or a native brook trout. The quest for Georgia’s trout is expected to generate an economic impact of some $172 million this year, according to the state Department of Natural Resources.

But whether you fish or not, Georgia is fortunate in having numerous mountain streams suitable for trout, which are super sensitive to water cleanliness and other environmental conditions. North Georgia’s mountains are the southernmost extent of trout streams in the eastern United States.

Of the three trout species in Georgia, the only native is the brook trout, which lives in higher-elevation mountain streams. Brown trout and rainbow trout have been introduced into streams at lower elevations — including a stretch of the Chattahoochee River in metro Atlanta downstream from Buford Dam.

The DNR raises the browns and rainbows in its three trout hatcheries and transfers the fish to suitable streams to accommodate anglers. A fourth hatchery, operated by the U.S. Fish and Wildlife Service, raises all three trout species.

The presence of trout bespeaks highly of a stream’s water quality and surrounding environment. Trout require cold, clean, swift-moving water with an unblemished stream bed of gravel to live, thrive and reproduce.

Cold water holds more oxygen than warm water, and trout critically need higher levels of dissolved oxygen in water than most other fish. Also, splashing streams add more oxygen from the atmosphere to the water.

Clean, clear water also is essential. A major threat to Georgia’s trout streams is silt washing off the land into the water from agriculture and development. When silt settles onto a gravelly creek bottom, it can smother trout eggs and aquatic insects that the fish feed on.

IN THE SKY: From David Dundee, Tellus Science Museum astronomer: The moon will be full on Tuesday. Venus and Jupiter are low in the west just after sunset. Mars is high in the southwest at dark. Mercury and Saturn are not visible now.