On June 1, 2011, the U.S. Fish and Wildlife Service provided notice of a proposed revision to the Riverside fairy shrimp’s designated critical habitat that would add approximately  2,678 acres, raising the total designated critical habitat to approximately 2,984 acres.  The additional lands proposed to be designated are located in Ventura, Orange, Riverside, and San Diego Counties in California.

The proposed revision is to a 2005 final critical habitat designation that identified 306 acres.  The notice recently issued by the U.S. Fish and Wildlife Service states that the proposed revision incorporates "new information specific to Riverside fairy shrimp genetics across the species’ range that was not available when we completed our 2005 final critical habitat designation . . . , and new information on the status and distribution of Riverside fairy shrimp that became available since the 2005 critical habitat designation for this species." 

Comments on the proposed designation must be received or postmarked on or before August 1, 2011.