“…Agassiz, 1865) persists in high numbers during the summer to winter, both in its native range along the American Atlantic coasts (Costello et al, 2006;2012) and in invaded habitats like the Black and Caspian Seas (Vinogradov et al, 2005), the North Sea (Riisgård et al, 2007), the Baltic Sea (Javidpour et al, 2009), and the Mediterranean Sea (Fuentes et al, 2010). The recent invasions of northern European waters have stimulated heightened interest in the role of M. leidyi as a competitor and predator of crustacean zooplankton, fish eggs, and larvae (e.g., Colin et al, 2010;Jaspers et al, 2011). An understanding of its ecology also requires quantification of its role as prey, but such studies are sparse (e.g., Oviatt & Kremer, 1977;Purcell & Cowan, 1995;Kreps et al, 1997;.…”