Lake Oahe’s aquatic food chain includes a smorgasbord of baitfish that are keeping healthy the lake’s gamefish populations.
According to South Dakota Game, Fish and Parks, there were an estimated 80 million baitfish in the lake as of 2017. Of those, around 55 million were rainbow smelt. That fish is native to Lake Champlain and later was introduced to the Great Lakes. From there, human introductions caused the smelt to spread west.
A flood in 2011 put a major dent in the population. It was that event that flushed most of the lake’s rainbow smelt downstream, according to the state. That turned out to be a big problem because smelt are oily. Oily fish are high in fat which, in turn, means they provide a lot of energy to the bigger fish that eat them.
The population has since rebounded, along with other baitfish in the lake. Game, Fish and Parks list emerald shiner, lake herring and gizzard shad as other baitfish. What is more, the state stocked gizzard shad in the lake to help rejuvenate the food chain.