Researchers monitoring threatened and endangered fish species in the Arkansas, Kansas, Gila, San Juan, Red and Platte rivers determined that when river fragmentation and groundwater withdrawals occur along with drought conditions, aquatic systems’ diversity can be put in jeopardy. 

The study showed that barriers or dams introduced into waterways can inhibit various species’ gestation cycle in rivers where free-flowing fragments are less than 100 kilometers.  The construction of dams can also encourage the influx of non-native fish, which often prey on native species.