The Status of Fishes in the Missouri River, Nebraska: Blue Sucker Cycleptus elongatus

Authors

Kirk D. Steffensen, Nebraska Game and Parks CommissionFollow
Sam Stukel, South Dakota Department of Game, Fish and ParksFollow
Dane A. Shuman, U.S. Fish and Wildlife Service - Great Plains Fish and WIldlife Conservation OfficeFollow

Date of this Version

Spring 3-23-2015

Citation

2015 Transactions of the Nebraska Academy of Sciences 35, 1–11

Abstract

Blue Sucker Cycleptus elongatus are a large-bodied, benthic fish that are considered an indicator species for riverine health. A combination of historic commercial fishing and anthropogenic modifications to riverine habitat led to blue suckers being listed as a candidate species for the federal threatened or endangered species list in 1993. However, they were never designated a federally protected species. Locally, Blue Suckers are currently listed as a Nebraska Natural Legacy Project’s Tier 1 species but population changes and trends have not been quantified. Therefore, the objective of this paper was to evaluate the current population status of Blue Sucker in the Missouri River along Nebraska’s border. Over 12,000 Blue Suckers were sampled in Nebraska from 2003 to 2012 as part of a targeted effort to characterize the benthic fish community in the Missouri River. Blue Suckers were rarely sampled upstream of Gavins Point Dam. Sampling results from this reach indicate this remnant population is comprised of mostly large adults with very limited reproduction. Capture frequency increased downstream of Gavins Point Dam with adequate reproduction and recruitment to sustain the population in these reaches. Gill net catch consisted of 14% Blue Suckers in the unchannelized reach downstream of Gavins Point and 23% of the benthic fish community in the channelized reach upstream of the Platte River. Age-0 Blue Suckers were most frequently detected in 2011 during the extreme flooding conditions but were also detected in higher abundance in 2006 when the river remained in its channel. The overall population downstream of Gavins Point Dam appears stable or perhaps slightly increasing. Blue Suckers, as with most native fish populations, were negatively affected when the Missouri River was highly modified through dam construction and channelization. However, reproduction and recruitment is occurring and Blue Sucker are not as imperiled as Pallid Sturgeon Scaphirhynchus albus or the native Macrhybopsis species.