Larval gizzard shad characteristics in Lake Oahe, South Dakota: A species at the northern edge of its range

Journal of Freshwater Ecology
By: , and 

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Abstract

Gizzard shad, Dorosoma cepedianum, have generally been restricted to the lower Missouri River impoundments in South Dakota. In recent years, gizzard shad numbers have increased in Lake Oahe, marking the northern-most natural population. These increases could potentially affect recreational fishes. Specifically, questions arise about larval gizzard shad growth dynamics and if age-0 gizzard shad in Lake Oahe will exhibit fast or slow growth, both of which can have profound effects on piscivore populations in this reservoir. In this study, we evaluated larval gizzard shad hatch timing, growth, and density in Lake Oahe. We collected larval gizzard shad from six sites from May to July 2008 and used sagittal otoliths to estimate the growth and back-calculate the hatch date. We found that larval gizzard shad hatched earlier in the upper part of the reservoir compared to the lower portion and that hatch date appeared to correspond to warming water temperatures. The peak larval gizzard shad density ranged from 0.6 to 33.6 (#/100 m3) and varied significantly among reservoir sites. Larval gizzard shad growth ranged from 0.24 to 0.57 (mm/d) and differed spatially within the reservoir. We found no relationship between the larval gizzard shad growth or density and small- or large-bodied zooplankton density (p > 0.05). As this population exhibits slow growth and low densities, gizzard shad should remain a suitable forage option for recreational fishes in Lake Oahe.

Additional publication details

Publication type Article
Publication Subtype Journal Article
Title Larval gizzard shad characteristics in Lake Oahe, South Dakota: A species at the northern edge of its range
Series title Journal of Freshwater Ecology
DOI 10.1080/02705060.2012.709887
Volume 28
Issue 1
Year Published 2013
Language English
Publisher Taylor and Francis
Contributing office(s) Coop Res Unit Leetown
Description 10 p.
First page 17
Last page 26
Country United States
State South Dakota
Other Geospatial Lake Oahe
Online Only (Y/N) N
Additional Online Files (Y/N) N