At one time gizzard and threadfin shad were thought to be the ideal forage fish for stocking impoundments, lakes and ponds with to provide an ample food source for bass and crappie. Over time however, the introduction of shad started causing problems that outweighed the benefits in a lot of waters. It turns out that the shad and game fish fry feed off of the same food. The shad are able to compete much more effectively for this food due to their structure. With the reproduction and growth rates of shad this could lead to a food shortage for game fish fry if the shad numbers aren’t properly maintained for the size of the body of water they are introduced to. When the food supply becomes scarce for game fish their growth rate, naturally, is inhibited. If the Gizzard shad is present this can further cloud the situation due to the fact that they can quickly grow to sizes to large for most of the game fish to eat.

Due to the fact that shad can become overcrowded in impoundments and cause problems with the game fish population, it is generally recommended that when fishing with these bait fish you dispose of any remaining shad at the end of you day in such a way that they cannot enter any body of water. In some states this is a requirement.