Standard Methods for Sampling North American Freshwater Fishes, second edition

Chapter 10: Warmwater and Coldwater Fish in Two-Story Standing Waters

Phaedra Budy, Gary P. Thiede, Robert Shields, and Travis Neebling

doi: https://doi.org/10.47886/9781934874769.ch10

We have completely reorganized the middle of the chapter. We now say that sampling the upper strata is the same as described in Chapter 3 and omit repetitive text describing techniques with that chapter completely. We made the same change for Chapter 7, including their stated changes. We then follow with the important considerations unique to sampling two-story water bodies. We added more details in Box 10.1, Linking the Strata: An Example from Flaming Gorge Reservoir, Utah-Wyoming, on species, depths, and sampling periods. We added another new box, Box 10.2, Linking the Strata: An Example from Starvation Reservoir, Utah.

Two-story fisheries occur in lakes or reservoirs characterized by two distinct spatial strata, warmwater and coldwater. These strata develop as the system begins to warm in the spring or summer in response to solar radiation and then separates into an upper warmwater stratum (epilimnion; hereafter, referred to as “the upper stratum”) and a lower coldwater stratum (hypolimnion; hereafter, referred to as “the lower stratum”) separated by the thermocline, a zone of rapidly declining temperatures with depth (i.e., stratification; Figure 10.1). Each stratum, or story, is dominated by fish species with very different physiological constraints, dietary preferences, and behavior.