Map of resting places of juvenile European catfish (Silurus glanis) in Byšická oxbow lake. A – Situation in
the period from 2nd November to 14th December 2010 (before oxygen deficiency) B – Situation in the
period from 28th December 2010 to 1st February 2011 (after oxygen deficiency).
Within the periods, the change in resting places (relocations) was minimal. All the fish that successfully
survived winter were assembled in two small areas with oxygen levels no lower than 2.2 mg·L−1. Two
individuals which did not move to these two sites died. The southern part of the oxbow is not depicted
because it is shallow, muddy and not inhabited by fish. C – Spatial distribution of DO values on the day
when DO minimum values were detected (21st December 2010). D – Spatial distribution of temperatures
on the day when DO minimum values were detected (21st December 2010).