The egg strands of perch were found at up to a depth of 20.2 m and, on average, 88% of perch spawning activity occurred at depths greater than 3 m. Almost all the egg strands were deposited on dead vegetation. Ignoring deeper strata may cause drastic underestimation of perch spawning success in lakes.
Keywords: aquatic vegetation; common reed; Eurasian water milfoil; lake management; Myriophyllum spicatum; Phragmites communis; SCUBA diving; spawning substrate