Seasonal weight-length relationship of Amur sleeper (Perccottus glenii Dubowski, 1877) in the Danube River drainage channel

Abstract

The Amur sleeper (Perccottus glenii), an indigenous species to the Russian Far East, northern China and the northern part of Korean Peninsula, has been considered an invasive alien species to European waters, where it may have negative impact on eggs and larvae of native fish species, on aquatic macroinvertebrate and larval amphibians. There were a few findings of the Amur sleeper specimens in Serbia during 2001-2003. The first record of established population was from the Danube River flood plain zone (1139 river km) in 2005. Our study includes 85 specimens collected in the Danube River drainage channel near Veliko Gradište (Serbia), in 2015-2016. The body length of specimens range from 35.78 mm to 140.68 mm, while the body weight range from 0.5 g to 40 g. Based on scale analyses, specimens have been determined at age of 0+, 1+ and 2+. The length-weight analysis does not show any differences between the regression slopes of samples from the two season.