Mismanagement of state water networks has brought some vital native fish species close to extinction during the California drought, environmental organizations and a sports-fishing group claimed in a federal lawsuit filed Thursday.

The lawsuit, by the California Sportfishing Protection Association and others, accuses the U.S. Bureau of Reclamation and the State Water Resources Control Board of violating environmental laws in divvying up diminishing flows of water through the delta of the Sacramento and San Joaquin rivers.

Bureau of Reclamation spokesman Louis Moore in Sacramento said federal officials had no immediate comment. State water board officials did not immediately return requests for comment.

"The environmental well-being of the five delta counties' 4-million residents is tied to a healthy delta, but our comments and protests" to water officials were ignored, Barbara Barrigan-Parrilla, head of Restore the Delta, a non-profit organization and a plaintiff in the case, said in a statement.

The suit came as state officials pull back harder yet on state taps while California moves into another summer in its driest four-year period on record. Mandatory water conservation by cities and towns begins this month. State officials have said they also expect to order further water cuts by farmers and others in coming days.

In their statement, the environmental and sports-fishing groups renewed accusations that state and federal water regulators were skewing water distribution from the two main state and federal water networks in California in favor of farmers over delta residents, fishermen and wildlife.

Drying, warming waterways in California's drought have brought one key species, the Delta smelt, to what biologists warn is the brink of extinction, the groups said. More than 95 percent of recent generations of Chinook salmon are dying in state waterways, the lawsuit adds.