Technical Report

Summary of the Rio Grande Silvery Minnow Population Monitoring Results From October 2004

URL: https://webapps.usgs.gov/mrgescp/documents/Dudley%20et%20al._2004_Summary%20of%20the%20RGSM%20population%20monitoring%20results%20from%2025-29%20October%202004.pdf

Date: 2004/11/08

Author(s): Dudley R.K., Platania S.P., Gottlieb S.J.

Publication: Report prepared for U.S. Bureau of Reclamation, 27 p.

Abstract:

The tenth sampling effort of the 2004 Rio Grande silvery minnow population monitoring program was conducted between 25 October and 29 October 2004 at 20 sites throughout the Middle Rio Grande. Five sites were located in the Angostura Reach, six sites in the Isleta Reach, and nine sites in the San Acacia Reach. A list of collection localities is appended (Table A-1).

Adult and juvenile fish were obtained by rapidly drawing a 3.1 m x 1.8 m small mesh (5 mm) seine through discrete mesohabitats. Fish were identified in the field, counted, and released at the site of capture. Rio Grande silvery minnow were also counted, identified to age-class, and released at the site of capture. No young-of-year fish (that could not be field identified) were collected during the October 2004 sampling. Figures illustrating catch rates (number of fish per 100 m2 sampled) were prepared for the ten focal species, including Rio Grande silvery minnow, for the purpose of comparisons between reaches.