Trypanosome infections of marine fish in the southern Barents Sea and the invasive red king crab Paralithodes camtschaticus

On the Atlantic blue crab ( Callinectes sapidus Rathbun 1896) in southern European coastal waters: Time to turn a threat into a resource?

“… the monitoring of the distribution and abundance of populations are key actions of the Green Crab Management Plan (see further);  connectivity assessed using molecular approaches for both Atlantic and Pacific populations (Roman, 2006;Darling et al, 2008;Tepolt et al, 2009); Ecological impact  currently included in the highest risk category of invasive species by the Norwegian biodiversity authority (Gederaas et al, 2012);  in 2002, Norway started a comprehensive research programme on the ecosystem impacts of the species in co-operation with Russia (Jørgensen and Nilssen, 2011);  destabilizing impacts have been demonstrated on the structure and functioning of benthic assemblages related with the generalist feeding habits of the species and its trophic shifts during ontogeny (Oug et al, 2011;Falk-Petersen et al, 2011;Fuhrmann et al, 2015; but see Britayev et al, 2010 for a counterexample);  indirect negative impacts have been suggested as vector of fish pathogens (e.g. trypanosome blood parasites by hosting the leech Johanssonia arctica: Hemmingsen et al, 2005Hemmingsen et al, , 2010;  designated as an aquatic nuisance species in the USA by the Aquatic Nuisance Species Task Force (ANSTF) since 1998;  in 2002 the ANSTF implemented a Green Crab Management Plan to assess the impacts and prevent, eradicate, and control the species;  negative impacts have been demonstrated on a number of benthic invertebrate taxa, including bivalves and other crustaceans (Floyd and Williams, 2004;Grosholz et al, 2000;Pickering and Quijón, 2011;Gehrels et al, 2016);  indirect negative effects have been suggested on physical characteristics of benthic habitats through bioturbation (Schratzberger and M. Warwick, 1999;Neira et al, 2006;Malyshev and Quijón, 2011;Lutz-Collins et al, 2016);  no parasite-related indirect effects have been emphasized to date; however, it has been suggested that the species may have a lower susceptibility to pathogens than other decapod crustaceans (e.g. Hematodinium infections: Hamilton et al, 2010); Economic Impact  negative effects have been indicated on the recruitment of valuable finfish species by feeding on egg-clutches (Mikkelsen and Pedersen, 2012; but see Dvoretsky, 2015 andPedersen, 2017);  non-univocal effects have been highlighted on the abundance of finfish and crust...…”