Daphnia Abundance and the Subsequent Effects on Endemic Bonneville

Location

Space Dynamics Laboratory

Event Website

http://water.usu.edu/

Start Date

3-25-2004 10:15 AM

End Date

3-25-2004 10:20 AM

Description

Daphnia pulex are important as a food source for juveniles of the 13 species of fishes in Bear Lake Utah/Idaho and can be the main food source of the endemic zooplanktivor, Bonneville cisco Prosopium gemmifer. Previous studies have suggested that Daphnia populations are cyclic in Bear Lake and may be related to lake water levels. We tested this relationship by examining the abundance and spatial distribution of Daphnia in Bear Lake during the summer of 2003, a year culminating a five-year drought period. We compared our results to previous samples collected during 1998-1996, a period characterized by both low and high water years. If Daphnia abundance is high in 2003 supporting the hypothesis that low water years promote Daphnia population expansions The relationship between climate and Daphnia may be due to direct impacts on water quality or may be related to water level effects on Bonneville cisco recruitment. We explore these possibilities and assess the potential impacts of water level changes on the population dynamics of this endemic planktivorous fish. Understanding linkages between lake water levels and Daphnia population dynamics would be an asset to the management of the lake.

This document is currently not available here.

Share

COinS
 
Mar 25th, 10:15 AM Mar 25th, 10:20 AM

Daphnia Abundance and the Subsequent Effects on Endemic Bonneville

Space Dynamics Laboratory

Daphnia pulex are important as a food source for juveniles of the 13 species of fishes in Bear Lake Utah/Idaho and can be the main food source of the endemic zooplanktivor, Bonneville cisco Prosopium gemmifer. Previous studies have suggested that Daphnia populations are cyclic in Bear Lake and may be related to lake water levels. We tested this relationship by examining the abundance and spatial distribution of Daphnia in Bear Lake during the summer of 2003, a year culminating a five-year drought period. We compared our results to previous samples collected during 1998-1996, a period characterized by both low and high water years. If Daphnia abundance is high in 2003 supporting the hypothesis that low water years promote Daphnia population expansions The relationship between climate and Daphnia may be due to direct impacts on water quality or may be related to water level effects on Bonneville cisco recruitment. We explore these possibilities and assess the potential impacts of water level changes on the population dynamics of this endemic planktivorous fish. Understanding linkages between lake water levels and Daphnia population dynamics would be an asset to the management of the lake.

https://digitalcommons.usu.edu/runoff/2004/AllPosters/22