Buying Time for Endangered Species
Missouri’s landscape has been changing with its growing human population. Our rivers and streams have been channelized (straightened, deepened and reinforced), reducing habitat for the spawning and rearing of some species of fish and other aquatic animals. Some rivers have also been dammed, keeping fish from reaching their historic spawning grounds. Pesticides, fertilizer and erosion have also degraded many of Missouri’s waterways.
Of the 12 federally endangered animal species found in the state, nine live in rivers. These include three fish and six species of native mussels. As steps are taken to stop the decline of these species, the Missouri Department of Conservation’s hatcheries are taking an active role by supplementing existing populations.
Several factors come into play when raising endangered species. The first challenge is obtaining the adults used to produce the offspring. Once the fish are at the hatchery, propagation work begins. Some fish spawn on their own in a hatchery setting, while hatchery staff must inject hormones into other species to induce spawning.
The endangered species raised in Missouri’s fish hatcheries include Topeka shiners and pallid and lake sturgeon. Endangered native mussels, such as pink mucket, fat pocketbook and scaleshell, are also raised.
Topeka shiners are federally endangered and are being produced at the Lost Valley Fish Hatchery. They are a small shiner that reaches a maximum length of 3 inches. They can only be found in two watersheds in Missouri.
The first shiners were taken to Lost Valley in 2000 to begin work on propagation. This was the first attempt at raising the shiners in a hatchery pond, and hatchery staff had to guess at the kind of pond environment they would need for spawning.
For the first three years, 60 to 80 adult shiners were placed in a rearing pond. Creek gravel was provided for them to deposit their eggs on, as they do in their natural environment. The water level and temperature were manipulated to simulate the type of stream pool where they might be found. At the end of the first three years, only a handful of young were raised. Hatchery staff realized that changes needed to be made for the next year.
For the fourth year, 100 shiners were placed in the pond along with nine orangespotted sunfish. The sunfish were added because most of the spawning observed in the wild has taken place at the edges of sunfish nests. It wasn’t long before the shiners were schooled around the