NATURA MONTENEGRINA, PODGORICA, 7(2): 285-289 LENGTH-WEIGHT REGRESSION AND DRY WEIGHT ESTIMATES FOR THE MAIN ZOOPLANKTON SPECIES OF BUVILLA RESERVOIR Spase SHUMKA, Spiro GRAZHDANIand Enkeleda NIKLEKA Agriculture University of Tirana Emai: sprespa@yaho.co.uk Key words: length-weight regression, dry weights, zooplankton species, bioindicators, biomass Synopsis In this paper are presented the data on biomass of the zooplankton of Bovilla Reservoir. The reservoir itself consist the main source for of drinking water for the Tirana capital city. Based on different bibliographical data there are existing dry weights for many zooplankton species (BOTTRELL et al., 1987, DUMONT et al., 1975, MALLEY et al., 1989, MICHALOUDI, 2005 etc.). Based on our calculations the dry weights were: 2, 225 μg Asplanchna priodonta, 0, 03 μg Brachionus angularis , 0, 021 μg Tricocherca sp., etc. During the investigated period 36 species were identified. Their qualitative and quantitative composition varied depending on locations. At this period the Cladocera and Rotatoria species were dominant, while the copepods has been following them. Out from the dominant species the Bosmina, Keratella and Macrocyclops albidus has been most abundant. Reservoirs defined in agreement with ICOLD have in comparison with lakes higher watershed area/waterbody area rate, shorter theoretical retention time, different basin morphology with deepest point at the dam and mostly deep outlet. Their ecosystems usually are considered to be more controlled by catchment area characteristics and by meteorological phenomena than most of lakes, due to larger watershed/reservoir volume ratios and therefore shorter retention time (SHUMKA, 2008). INTRODUCTION Watershed basin of Bovilla covers a total area of 98 km2, including the Tërkuza upriver and of some of its effluents, rivers or torrents. It extends behind Kruja-Dajti mountain chain, starting from the narrow gorge of Zall-Herri. The relief of the zone is vertically and horizontally very fragmented, forming often deep valleys with narrow gorges. The slopes and crests are mainly composed of limestone, while the valley bottoms are sandy combined with clays. As regards vegetation, until 600 m above sea level, there dominate the Mediterranean evergreen shrubs, increasing the altitude