The concentration in the pool was maintained by slowly introducing part of the rotenone into the riffle at the head of the pool.
Tables 12-16 list all fish obtained at the upper Neosho station by means of the shocker, seines, and rotenone.
Therefore, rotenone was more effective in deep water than was the shocker.
Pools in which rotenone was used had areas of as much as one-half acre and depths in excess of six feet.
rotenone acts more slowly than cyanide, allowing more of the distressed fish to rise to the surface.
The rotenone was mixed with water and applied by hand, or into the backwash of an outboard motor.
In 1958 and 1959 rotenone was applied to the upper end of a pool and mixed by agitating the water.
Pool at the upper Neosho station in which rotenone was used, Sec.
In all three years of the study, large samples were obtained by means of rotenone in the same pool at the upper Neosho station.
rotenone was used in a few small pools in efforts to capture complete populations.