Pond owners often notice that fish behave differently throughout the year, and understanding why can help improve pond management, according to Scott Jones, small impoundment Extension specialist at the University of Arkansas at Pine Bluff (UAPB).
“Fish activity, health and survival are strongly influenced by water temperature,” Jones said. “Unlike mammals, most fish do not regulate their internal body temperature. Their metabolism, movement, digestion, immune response and oxygen demand all change with the temperature of the water.”
In spring and fall, fish tend to be more active and easier to catch. During mid-summer, they often feed early in the morning or late in the evening, while winter can make fish seem almost absent.
Each species has an ideal temperature range for growth. Largemouth bass, for example, thrive near 80°F, while rainbow trout prefer around 60°F. When water temperatures fall outside these ranges, fish can experience metabolic stress that affects growth, behavior, and overall health.
Cold water can slow metabolism, reduce feeding and digestion, weaken swimming strength, and compromise immune function. In Arkansas, channel catfish are particularly vulnerable during winter, especially in ponds with low hardness. “Affected fish may appear thin, pale, or develop fuzzy gray or brown patches,” Jones said. “These conditions, often called ‘winter fungus,’ can cause gradual losses from December through February.”
Warm water presents its own challenges. As temperatures rise, fish metabolism increases, boosting activity, digestion, and oxygen demand—just as warm water holds less dissolved oxygen. Fish may move to deeper or shaded areas, but if oxygen is low, they become stressed, which can reduce growth, weaken immunity, and even lead to death.
“Fish are rarely affected by a single stressor alone,” Jones said. “Temperature extremes, poor water quality, low oxygen and inadequate nutrition can combine to overwhelm a fish’s ability to maintain balance.”
Jones encourages pond owners to monitor seasonal changes and adjust management practices accordingly. Maintaining good water quality, minimizing disturbances during extreme temperatures, and understanding fish behavior can help improve survival, growth, and pond performance.
“By recognizing temperature as a central driver of fish health, pond owners can anticipate seasonal challenges and keep their ponds productive year-round,” he said.
For more information about pond management, contact Scott Jones at (870) 575-8185 or [email protected], or reach out to your local county Extension office.
