Length-weight relationships of 28 fish species caught from demersal trawl survey in the Middle Black Sea, Turkey

This study provides updated the length-weight relationships and Fulton's condition factor of 28 fish species belonging to 23 families from the Black Sea. Samples were collected along the depths between 0-100 meters by demersal trawl surveys conducted seasonally from May 2017 to September 2019. A total of 83,885 specimens were collected. The length-weight relationships and Fulton's condition factor, minimum, maximum and mean lengths, total weights, descriptive statistics, and growth type were provided for all the species. The results indicate that LWR parameters of b varied from 2.2039 to 3.737 and Fulton's condition factor varied between 0.004 and 1.18. These findings could be useful for monitoring and management of sustainable fisheries and habitat health

Monthly variation in the morphological characteristics of Trichodina sp. (Ciliophora: Peritrichida) found on whiting Merlangius merlangus euxinus

To determine the existence and extent of seasonal variation in morphological characteristics of Trichodina sp., sixty whiting Merlangius merlangus euxinus were sampled monthly for one year, from the Eastern Black Sea coast of Turkey, using a line and hook. Strong seasonal morphological variations were detected; the denticle span, blade length and ray length showed significant seasonal variation, especially in June. The timing of primary production in the Black Sea and the changes in cellular organelles suggested a negative relationship between the body diameter of trichodinids and food availability in the surrounding environment