During the late 1980s, carnivorous ctenophore Mnemiopsis leidyi, along with the other invaders, had been transported to the Black Sea from the coasts of eastern Atlantic, which resulted in ecosystem damage for the region (Vinogradov et al., 1989; Kideys, 2002a; Ghabooli et al., 2011). One of the major factors, resulted in the rapid expansion of the M. leidyi population during its initial invasion into the Black Sea, was the absence of a specialised predator (Kideys and Shiganova, 2001; Kideys et al., 2004a, 2004b, 2005, 2008; Roohi et al., 2008). The Black Sea, besides being a recipient area, also serves as a donor area for some invasive species that then spread further to the Sea of Azov, the Sea of Marmara, and the eastern Mediterranean Sea and, in some cases, to the Caspian Sea (Shiganova, 2010). |