FISH KILL
FISH KILL
White Bass die-off in Lake Oahe
ND Game & Fish Dept .
Periodic kills of adult white bass have occurred in previous years , though fisheries biologists say there ’ s no known cause why this occurs .
Dakota Country Staff Report
“ The timing of this particular fish kill aligns with the white bass spawning period and this was likely the stressor that made these fish susceptible to the bacterial infection . Other recent white bass fish kills on Lake Oahe ( 2009 and 2005 ) were also caused by bacterial infection but those fish kills occurred in August when high water temps were most likely the stressor that contributed to those events .”
A disease that periodically affects some fish in the Dakotas , Aeromonas , struck again in early July through much of Lake Oahe . The largest kill , as noted by North Dakota fisheries biologist , Paul Bailey , was worse along the ND / SD border .
“ We observed the greatest concentrations of dead fish from a couple miles south of the Cattail Bay / Ft . Yates area to the ND / SD border ,” he said .
The dead fish were seen in abundance in several areas of Lake Oahe , comprised largely of white bass . Anglers began noticing dead fish along shorelines in early July . After authorities were notified , tests began when samples of white bass tissue were later confirmed from the University of Minnesota to be Aeromonas bacteria .
While such kills from this disease is mostly confined to adult white bass , there were , Bailey said , “ a few fish of other species that succumbed as well .”
White bass kills from this bacteria are not rare . Other die-offs occurred in Lake Oahe in 2005 and 2009 . ND Fisheries confirmed , however , that the recent event was not as severe as those previous .
When asked why the kill seems to affect only adult white bass , Bailey said this particular event was a bit unusual because the kills usually occur in relation to warm water , often in late summer . That was not the case with the most recent die-off .
“ There are a variety of causes for fish kills , the most common being low dissolved oxygen levels in the winter ,” Bailey explained . “ However , disease outbreaks have also led to fish kills in the Dakotas and that
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