Native fish play an important role in the environment. The Murray-Darling Basin is home to over 60 native fish species, including freshwater fish, estuarine fish and migratory fish between rivers and seas. Many of these species are endemic to Australia and some are found only in the Murray-Darling Basin. Strong native fish schools help keep rivers healthy by cycling nutrients such as carbon and nitrogen and maintaining productive food webs. Secondly, native fish schools must be protected and restored. If you could glean so much knowledge from just one species group, imagine the other information contained in the DNA of dozens of other species unique to that state. And with all the changes we're making — dams, aqueducts, reservoirs — California's native fish are becoming increasingly vulnerable. Not only do we risk losing it, but it also shows that the well-being of some of our vital freshwater ecosystems may not be stable. Depending on how we use river water. , the river's natural flow, time and pattern changed. River currents affect the life cycle of native fish, and different species require different currents. Barriers such as dams, weirs, and very dry climatic conditions (which can stop flow) can prevent native fish from reaching where they need to reach their feeding and breeding grounds. Water for the environment is used to complement other management techniques such as fish ways and tree stumps and to improve native fish populations, including endangered species. Giving current to the right place at the right time allows native fish to swim where they need to feed, grow and reproduce. The goal is to maintain and improve the health of native fish populations, which will help restore the health of entire river systems. Native fish are of great social and cultural value to watershed communities. I have. Recreational fishing is a major recreational activity throughout the basin, generating $1.3 billion in annual revenue. A hobby fisherman needs a healthy fish population to keep fishing. Indigenous fish are of cultural importance to indigenous peoples. The ability to fish for bait and use the basin's surroundings for recreation and family and community gatherings maintains a connection to both land and water. All of these ecological, economic and cultural values ​​depend on healthy native fish populations. Releasing water into the environment can help restore native fish populations so we can all benefit from healthy rivers. There are things that do not coexist with salmonid fish. Previous studies of the exotic brown trout Salmo trutta and the disjointed distribution of native galaxies showed native extinction unless large waterfalls impeded upstream migration of trout. We predicted that water extraction may be another factor controlling the spatial distribution of both invasive and native fish in the Manuherikia river system. Their predominantly uneven distribution in this river is mediated by water extraction for irrigation, along with pool habitat availability and valley slope. Trout are more susceptible than native fish to stresses associated with low currents, which appears to limit their ability to clear galactic populations from low-watershed locations with high levels of water attraction.