185
Arctic Yearbook 2015
transmission caused by microscopic pathogens (CAFF 2013). Additional research concentration in
these areas may have high potential net benefits.
Microorganism bio-invasions are a rather conspicuous feature of marine ecosystems overall,
particularly because of the ballast water tanks which may carry hundreds of trillions (Society for
General Microbiology 2008) of microorganisms on just a single tank or a hull can harbor whole
ecosystems of microorganisms. The chances of their individual survival might be relatively low, but
the increasing shipping activity in the Arctic increases the overall threat level. Fighting the challenge
of microorganism invasions and managing them effectively has never been easy. One can argue that
preventing introduction and new infestation would be an optimal solution but the limited amount of
research to date does not allow strong conclusions (Burnett et al. 2008; Burnett, Pongkijvorasin &
Roumasset 2012; Kaiser & Burnett 2010). Besides the general experience obtained so far, which
indicates that particularly for marine ecosystems, preventing invasions has proved the most effective
and economically viable way to mitigate their impacts (Carlton 2001; Williams et al. 2013), the diverse
realm of Arctic invasions paves the way towards intensifying joint prevention efforts.
Apart from the microorganisms discussed above, existing fears for future invasions are also informed
by northward migrations in temperate waters and include species that range from the European green
crab (Carcinus maenas) (deRivera, Steves, Ruiz, Fofonoff & Hines 2007), which as a voracious predator
may pose a significant threat to Arctic marine life, to salmon (Nielsen, Ruggerone & Zimmerman
2013). Additionally to the above, other non-indigenous species have also been identified in Arctic and
sub-Arctic waters but cannot yet be listed as confirmed invasions (Molnar, Gamboa, Revenga &
Spalding 2008):
Table 1: Suspected Arctic introductions
Species name
Binomial name
Soft-shell clams
Mya arenaria
Hydroid
Ectopleura crocea
Naval shipworm
Teredo navalis
Higher
Taxa
Invertebrate
Mollusc
Ecoregion/ location of identification
Invertebrate
Cnidarian
Invertebrate
Mollusc
Eastern Bering Sea
Acartia copepod
Acartia tonsa
Invertebrate
Arthropod
Crustacean
Zebra mussel
Dreissena polymorpha
Invertebrate
Mollusc
Kourantidou, Kaiser & Fernandez
North and East Iceland
Eastern Bering Sea
East Greenland Shelf
West Greenland Shelf
Northern Grand Banks - Southern
Labrador
Northern Labrador
Baffin Bay - Davis Strait
White Sea
Hudson Complex