Morphology of the Eurasian perch (Perca fluviatilis): A multivariate approach

Abstract

The morphology of the Eurasian perch (Perca fluviatilis L.) taken from three sites, the Danube (river), Stari Begej (channel) and Lake Gruzansko (reservoir), was analyzed by multivariate statistical methods. The main morphological intervals that were identified in the life history of the perch were: younger and older fingerlings (YOY) and young juveniles (1+) as the one interval, preadults (2+ and 3+) as the second interval, and adults (≥4+) as the third one. It was evident that the formation of morphological features differed in examined samples, since mode and amount of characters change in particular month stages of fingerling and age classes of older perch were not the same. This applies also to alterations in the morphology until adulthood. Even then, perch from particular biotopes differed. Thus, delimited divisions of the life cycle coincided rather well with the main feeding periods in the life history of the perch, and were apparently related to growth, since the slowly growing perch lagged behind in the development of morphological features, as well as in the shift to piscivorous feeding. Allometry was not observed, suggesting that even if it appeared it had a short duration and is of small importance.