Are there correlations between the levels of fluctuating asymmetry in Pelophylax ridibundus (Anura: Ranidae) meristic morphological traits and morphological parameters used for assessing their physical fitness (health status)?

The degree of developmental stability of individuals and populations is most often estimated by their level of fluctuating asymmetry (FA) - the random deviations from perfect symmetry. In our previous work, we recorded high levels of FA (FAMI index: frequency of asymmetric manifestation of an individual) in Pelophylax ridibundus populations that inhabit biotopes at Sazliyka River, south Bulgaria with high levels of anthropogenic pollution (domestic sewage pollution). At the same time, in the biotopes located in the upper reaches of the river (less disrupted habitats), the populations showed low levels of FA. Currently, we present the results of the study of the values of several morphological parameters: snout-vent length (SVL), body weight (BW), and body condition factor (CF) in the same populations of P. ridibundus. In addition, we evaluate the correlation between the values of these morphological parameters and the values of fluctuating asymmetry (the FAMI index), using the Kendall rank correlation analysis. The analysis of the relationships between the parameters characterizing the physical fitness of frogs and the indicator of developmental stability - the FAMI index - did not establish statistically significant correlations in the analyses in the whole groups of P. ridibundus from each site and in the correlations between sexes. We believe that the approaches to the study of developmental stability (analysis of fluctuating asymmetry levels) and those related to the assessment of physical fitness (health status) of frogs should be applied independently of each other.