Technical Report
Rio Grande Silvery Minnow Salvage 2011
Date: 2011/01/01
Author(s): Remshardt W.J., Archdeacon T.P.
Publication: Prepared for U.S. Bureau of Reclamation, 30 p.
Abstract:
Between 25 June and 26 October 2011, a total extent of 40.0 miles of the main channel of the Middle Rio Grande became intermittent in the Isleta (12.9 miles) and San Acacia (27.1 miles) reaches. Including multiple drying events, 83.7 river miles were salvaged in the San Acacia reach, and 59.2 in the Isleta reach. A total of 8,244 Rio Grande silvery minnow were salvaged from isolated pools, transported, and released alive at locations within the same reach as they were salvaged. The take by mortality of 116 Rio Grande silvery minnow was attributed to water operations in the Middle Rio Grande during the 2011 irrigation season and assigned as incidental take. The level of estimated incidental take (observed multiplied by 50) was 5,800 and was well below the limits established under the determination of incidental take number of 459,077 individuals for the 2011 season. The loss of 336 Rio Grande silvery minnow was attributed to U.S. Fish and Wildlife Service permit activities. Going into the 2011 salvage season, lower presalvage catch rates meant that the allowed incidental take number was set lower in 2011 than 2010. Although we salvaged more miles and days in 2011, the number of fish observed both alive and dead was lower in 2011.