Updated distribution, population genetic structure, and local occurrence patterns of Longnose Sucker (Catostomus catostomus) and Lake Chub (Couesius plumbeus) in the Black Hills of South Dakota.
Abstract
Longnose Sucker (Catostomus catostomus) and Lake Chub (Couesius plumbeus) were
once thought to exist throughout the Black Hills, South Dakota; however, recent surveys
have documented dramatic declines. To inform future conservation, I provide: (1)
updated regional and local distributions, (2) descriptions of occurrence patterns and size
structure, (3) assessments of the influence of stream characteristics on relative
abundances, and (4) describe the interrelatedness and regional population genetic
structure for both species. Longnose Sucker were restricted to two major tributaries of the
Redwater subbasin, and more often captured in stream reaches with steep banks and more
even substrate composition. Additionally, greater species richness and higher width-depth
ratios were important stream characteristics. Lake Chub were most often captured in
riffle macrohabitats within a single river system in the Middle Cheyenne – Elk subbasin.
Stream reaches with fewer trout and greater native species richness were important
factors in Lake Chub occurrences. Reduced representation genome sequencing suggests
that Longnose Sucker move throughout the Redwater subbasin. Genetically distinct Lake
Chub populations are found in the Middle Cheyenne – Elk Subbasin. These results
provide crucial data to better understand the resiliency, redundancy, and representation of
these fishes and inform their conservation in the Black Hills of South Dakota.
Subject
Biology
Aquatic Science
Longnose Sucker