Accepted Article This article has been accepted for publication and undergone full peer review but has not been through the copyediting, typesetting, pagination and proofreading process, which may lead to differences between this version and the Version of Record. Please cite this article as doi: 10.1002/nafm.10343 This article is protected by copyright. All rights reserved. Article type : Article Spatial and Temporal Variability in a Large Reservoir Fish Assessment and Application of a Stratified Random Sampling Approach Benjamin J. Schall ac , Casey W. Schoenebeck ad , and Keith D. Koupal b a Department of Biology, University of Nebraska at Kearney, Bruner Hall of Science, 2401 11th Street, Kearney, Nebraska, 68849, USA b Nebraska Game and Parks Commission, Fisheries Division, 1617 First Avenue, Kearney, Nebraska, 68847, USA c Current Address: South Dakota Department of Game, Fish and Parks, 4500 S. Oxbow Ave, Sioux Falls, SD 57106 d Current Address: Minnesota Department of Natural Resources, 23070 North Lakeshore Drive, Glenwood, MN, 56334 Abstract Sampling is often standardized with regard to time and space to monitor population characteristics. Effective sampling of large reservoirs can be complicated by the inherit bias of habitat variability along the reservoir gradient. Our objective was to assess spatial and seasonal distribution patterns of target and non-target fish species in a large reservoir to identify potential sources of bias. A multitude of fish community and habitat characteristics were measured during seasonal (spring, summer, and fall) gill net surveys in 2015 and 2016