Diversity and Ecology of the Freshwater Crayfish in the Northwest of the Republic of Srpska

Abstract

The existence of three autochthonous crayfish species is confirmed in the northwest of the Republic of Srpska: Astacus astacus, Pontastacus leptodactylus and Austropotamobius torrentium. There is a lack of information on the European crayfish population status in the Republic of Srpska comparing to other European countries. Our aim is to generate the latest information on crayfish distribution and population status, and make it the basis for managing and preserving natural population. The present study was implemented in the period from April 2018 until September 2019. Mostly distributed crayfish species in the Republic of Srpska is A. torrentium registered in 12 locations at altitude ranging from 201 to 846 m in the Vrbas river basin, but it is also present in the tributary streams of the Sana river, in ecologically-like habitats, in particular in relatively clear waters with low quantity of organic substances (I and II water category). A. astacus is mainly present in the Crna river basin, forming both river and lake population (a great number thereof is present in the Balkana lake) – waters with oxygen concentration over 8g O2 m-3 and with BOD5 values below 0.5g O2 m-3. P. leptodactylus was found only in two locations: The Matura river (in Srbac) and the Vrbas river (upstream from Razboj), in the I-III category waters. The identified possible threats for autochthonous crayfish in fresh water ecosystems of the Republic of Srpska require urgent water management and preservation actions.

Morphometric characteristics and condition indices of stone crayfish Austropotamobius torrentium (Shrank, 1803) from the Mlinska River

“…The stone crayfish occurs only in the source and upper parts of streams with stone bottoms (Kappus et al, 1999), although they sometimes can be found in clean rivers and lakes (Renz and Breithaupt, 2000). The above-mentioned species of crayfish is present and dominant in Bosnia and Herzegovina (Trožić-Borovac, 2011;Roljić, 2020), as well as in the neighboring countries, Serbia (Simić et al, 2008), Croatia (Maguire and Gottstein-Matočec, 2004), Montenegro (Rajković, 2012). The existing populations are the remnants of a wider historical population that was ravaged by duck plague by the end of the 19 th and during the 20 th century (Budihna, 1991).…”

“…As preliminary studies determined the presence of this species in Mlinska River (Roljić, 2020), our intention was to describe its morphometric characteristics. This research aims to determine whether there are differences between the morphometric characteristics of males and females and to observe the condition status of the captured individuals in order to estimate the possible pressure on the population of stone crayfish.…”

Production of Planting Material of Raspberry Variety

“…For these reasons, only raspberry planting material produced in a modern way, which is under the professional and health control of authorized persons by the competent Ministry of Agriculture (in Montenegro), should be used for raising new plantations. The highest quality raspberry shoots are obtained from rootstocks that are raised from varietal pure and healthy planting material, in separate and closed spaces (Lolić, 2018).…”