The combination of high water, longer days and warmer temperatures flips a switch in spring spawning fish species like walleye, perch, northern pike and rainbow trout.
Water temperature needs only to increase two or three degrees for some fish to start looking for places to spawn.
Daylight length rules everything on land from plants to animals. Yet daylight is also noticed underwater; even in muddy water.
High water may encourage fish to spawn, but it can also be a danger. Newly deposited eggs can be smothered from too much silt in the water. Spring wind storms and crashing waves can damage the developing eggs of perch, walleye and northern pike. Young fish can be swept out of their protective cover by surging flood water.
All of which explains why, depending on the species, female fish deposit thousands of eggs: Only a small portion survive to become adults.
More water, daylight and rising water temperatures affect other species that depend on water, too, like amphibians.
Right now, temporary pools of prairie water are home to frogs, toads and salamanders.
Boreal frogs are heard everywhere in the spring and early summer. During their breeding season, their loud, short chirp resembles the slow running of a thumb over the teeth of a comb and seems to come from every prairie pond and water-filled roadside ditch.
By midsummer, the inch-long frogs will disappear underground, beneath vegetation, into water tanks, or even under building foundations — anywhere they can keep their skin moist.
Joining the boreal frog in those pools may be several toad species and the tiger salamander, perhaps the weirdest looking creature on the prairie. Its body features blotches of olive or pale-yellow on a black or dark green background.
Water gives life to so many species.
— Bruce Auchly, Fish, Wildlife & Parks