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Energy, Climate change, Environment

Alien Species

Alien species are species living outside their native distributional ranges, having arrived as a result of human activities. Globally, alien species are considered the third most important threat to biodiversity after habitat loss and fishery. Alien species have the potential to impact the environment and economy, for instance by disrupting the food web or by carrying diseases or parasites.

Little is known about which alien species have reached the Arctic area, let alone established there, or what impact they may have. It is therefore necessary to have access to up-to-date information about the presence of alien species in the Arctic region. In this challenge information was gathered and presented on the introduction and distribution of alien species in the Arctic Ocean and on their (potential) impact on the ecosystem and economy.

Objective of the challenge
The objective of this challenge was to provide a table and digital map of alien species in the Arctic sea basin. The information includes:

  • species name
  • family (fish, algae, mammals, sponges etc)
  • year of introduction
  • reason for introduction (climate change, ballast water discharge etc)
  • geographical area
  • impact on ecosystem
  • impact on economy

Indicators are used to assess (potential) impacts of alien species on ecosystem and economy.

Aliens Russian buoy Aliens Shipping

Main results
There is no comprehensive and Arctic-specific database for alien species available. Therefore information on aliens in the Arctic Ocean was compiled from various database sources and scientific literature into a new database focused specifically on Arctic alien species. This is presented in Table 1, containing 101 established and potential alien species in the Arctic. Further detailed information is provided for each of the species separately, including species-specific taxonomy, geography, introduced range, year of introduction, vector or reason for introduction and (potential) environmental and/or economic impacts.

The available information on the identified alien species considered established in the Arctic region (from GBIF data) suggests that the majority were introduced via shipping (hull fouling or ballast water), and some via fisheries or aquaculture activities. While these activities may increase the speed of local dispersal and range extension, the temperature range of most of these species suggest that they may also be able to naturally disperse in the Arctic. As many of the established species were fouling species, habitats with hard substrates are likely to be the most sensitive to potential colonisation, while sheltered bays and inlet areas may also be sensitive to colonisation by planktonic species. While many species may have negligible effects, those that are ecological engineers or cause cascading effects in the food web may disrupt the functioning of the ecological system. Species that interfere with fisheries or aquaculture may also have an economic impact in the area. For more information, see below ‘Established Alien Species in the Arctic’.

Interactive digital maps are developed for each of the identified species to show areas in the Arctic where marine alien species have been reported as introduced. These can be find here.

Lessons learned
The research done for the Alien Species Challenge highlighted several gaps in knowledge that limit the comprehensiveness of the information available. These knowledge gaps consequently limit our ability to detect and predict the presence and (potential) impact of alien species in the Arctic.

In general:

  • There was no existing clear and complete overview of alien species specifically in the Arctic Ocean.
  • The availability of data on the presence of alien species in the Arctic and the distribution of these species in the Arctic was scarce.
  • The border defining the Arctic region is unclear, this made searching for Arctic-specific information difficult.
  • The status of a species as ‘alien’ or ‘native’ is not always clear due to the lack of regular monitoring in the Arctic area.
  • Databases that deal with alien species do not include the Arctic region, whereas databases that concern the Arctic region, do not, or only partly, cover the species identified to be alien
  • In total 101 marine alien species in the Arctic were identified from the literature. The information available relied on sporadic scientific studies that were limited in time and space (giving no indication of change), and is therefore potentially incomplete and quickly out of date. Continued and systematic research is necessary to maintain an up-to-date and relevant list of alien species.  
  • Observations of Arctic alien species are often based on presence in ballast water (in Canada and Svalbard), not on actual settlement and establishment in the marine environment.
  • Biological and environmental data is often lacking for the identified Arctic alien species
  • Reliable and unbiased reports on (potential) impacts of alien species in the Arctic are scarce.
  • The effect of climate change on the ability for certain species to expand their range to include the Arctic is currently unclear.

In particular:

  • Some source websites were only available in Norwegian or French (although it is unclear if they provided the appropriate data). Where English versions were available, they were often less complete than the original version.
  • Some source websites were not user-friendly. Data was often difficult to access and required various search methods for different websites.
  • No databases were found in Russian or Chinese. Whether these do not exist (publically) or were not found due to the language is unclear.
  • We could not access data that was not publically available, and it is unclear if these data contain more appropriate information.


  • Develop standard monitoring for detecting alien species in the Arctic, particularly in areas where human activity is regular or increasing such as on Svalbard. This can consist of annual monitoring by sampling sessile, plankton, and soft sediment in main commercial ports. Analysis can consists of traditional taxonomic identification and/or more innovative methods such as DNA barcoding.
  • Improve current databases by adding Arctic areas to alien species databases and adding alien species information to Arctic databases.
  • Improve communication and coordination with other national monitoring in Russia and Canada to further obtain comprehensive, standardised and reliable Arctic-specific information. In the near future a new version of the Norwegian black list for alien species is expected that may provide further input on the presence, distribution and potential impacts of alien species in the Arctic.
  • Stimulate research, including experimental studies, to fill the knowledge gap about which, to what extent, and in what circumstances alien species may have an impact on the Arctic ecosystem and economy.
  • Stimulate research to make informed projections about the effects climate change may have on the introduction of alien species to the Arctic.

References (most relevant)


 Table 1. Overview of marine alien species in the Arctic

Organism Type Group Species Observed in Vector Introduction Potential dispersal vector Temperature Range Potential Impact
Bryozoa Bryozoa Schizoporella unicornis Svalbard and Jan Mayen Ballast water; ship fouling; aquaculture Hull fouling 7-19 °C Multiple species impact
Crustacean Amphipoda Crassicorophium bonellii Russia   Hull fouling 3 - 17 °C  
Crustacean Amphipoda Gammarus cf. zaddachi Norway   Ballast water    
Crustacean Amphipoda Jassa marmorata Svalbard and Jan Mayen Hull fouling Hull fouling -2 - 27 °C Multi-species impact (ecosystem engineer - creator of novel habitat)
Crustacean Cladocera Acantholeberis curvirostris Norway Ship fouling Hull fouling    
Crustacean Cladocera Evadne nordmanni Russia Ballast water Ballast water 1-25 °C  
Crustacean Copepoda Acartia clausii Iceland Norway Russia Ballast water Ballast water    
Crustacean Copepoda Anomalocera patersoni Norway Ballast water Ballast water 6.6 - 18.9 °C  
Crustacean Copepoda Calanus helgolandicus Iceland Norway Ballast water Ballast water -0.77 - 24.7 °C  
Crustacean Copepoda Centropages hamatus Iceland Russia Ballast water Ballast water -0.9 - 23.6 °C  
Crustacean Copepoda Oithona similis CA Greenland Norway Russia Svalbard and Jan Mayen United States Ballast water Ballast water -1.9 - 25.9 °C  
Crustacean Copepoda Pseudocalanus minutus Russia United States Ballast water Ballast water -1.9 - 19.3 °C  
Crustacean Copepoda Pseudocalanus newmani Russia United States Ballast water Ballast water -1.9 - 19.3 °C  
Crustacean Copepoda Temora longicornis Iceland Norway Russia Ballast water Ballast water -0.9 - 16.5 °C  
Crustacean Decapoda Cancer pagurus Norway Ballast water Ballast water    
Crustacean Decapoda Carcinus maenas Norway Ballast water; aquaculture Ballast water 0 - 33 °C Single species impact; multiple species impact
Crustacean Decapoda Chionoecetes opilio Svalbard United States Ballast water; Hull fouling -1 - 10 °C  
Crustacean Decapoda Paralithodes camtschaticus Norway Fisheries   -1.7 - 11 °C Multiple species impact; affects entire ecosystem functioning; effect on fisheries
Fish Fish Esox lucius Norway Sweden Fisheries   1 - 29 °C Single species impact; multiple species impact; affects entire ecosystem functioning; effect on fisheries
Fish Fish Oncorhynchus mykiss Norway Sweden Aquaculture   0-25 °C Single species impact; multiple species impact; effect on aquaculture
Fish Fish Platichthys flesus Norway Drift; Shipping   5 - 25 °C Multiple species impact
Fish Fish Salvelinus fontinalis Norway, Sweden Aquaculture   ? - 25 °C Multiple species impact; impact on species with high conservation value; affects entire ecosystem functioning
Macroalgae Macroalgae Bonnemaisonia hamifera Norway Probably introduced unintentionally with shellfish or in the hull fouling of vessels. Secondary spread occurs by drift with water currents or attachment to floating objects (hooks enable entanglement).   -1 - 29 °C Multi-species impact (It may become the dominant alga in certain regions competing with other algae and seagrasses)
Macroalgae Macroalgae Codium fragile Norway The vector to Europe is unknown; secondary dispersal was by movement of shellfish for mariculture, transport on ship hulls and net fouling.   Though a warm temperate species with temperature optimum at 24 °C, growth and reproduction are still possible at 12 °C, adults can survive winter temperature of -2 °C. Economical (It fouls shellfish beds, smothering mussels and scallops, clogging scallop dredges, and interfering with harvesting. It fouls fishing nets, wharf pilings and jetties. It causes a nuisance to humans when it is swept ashore and rots); Ecological (It alters benthic communities and habitats, its dense fronds hinder movement of large invertebrates and fish along the bottom, and increases sedimentation.)
Macroalgae Macroalgae Chroodactylon ornatum Norway Sweden Oyster aquaculture transports; hull fouling; ballast water Hull fouling    
Macroalgae Macroalgae Dumontia contorta Iceland Norway        
Macroalgae Macroalgae Fucus cottonii Norway Ballast water; ship fouling Dry ballast and hull fouling    
Macroalgae Macroalgae Fucus serratus Iceland Norway       Multi-species impact (when established, F. serratus becomes dominant by forming a canopy cover in the lower part of the shore, reducing or eliminating the cover of other canopy forming algae)
Mollusc Mollusc Cerastoderma edule Norway Ballast water; drift Ballast water 7 - 34 °C  
Mollusc Mollusc Mya arenaria Norway Ballast water Ballast water (as larvae) 1 - 28 °C Single species impact
Mollusc Mollusc Mytilus galloprovincialis Svalbard Ballast water Ballast water   Multiple species impact; ecosystem engineer - creator of novel habitat; effect on aquaculture
Nematoda Nematoda Axonolaimidae Norway Svalbard and Jan Mayen Ballast water Ballast water    
Phytoplankton Phytoplankton Heterosigma akashiwo Russia Ballast water   -1.9 - 15 °C Single species impact
Plant Plant Cotula coronopifolia Norway Sweden Range extension due to climate change; birds   ~ -10 - 30 °C Multiple species impact; ecosystem engineer - creator of novel habitat
Polychaeta Polychaeta Heteromastus filiformis Greenland Norway Ballast water; ship fouling Ballast water and hull fouling -1.7 - 26.8 °C  
Polychaeta Polychaeta Scolelepis foliosa Norway Svalbard and Jan Mayen Ballast water Ballast water -1.5 - 16 °C  
Polychaeta Polychaeta Scolelepis korsuni Norway Ballast water Ballast water -1.5 - 16 °C  
Polychaeta Polychaeta Scolelepis tridentata Norway Ballast water Ballast water -1.5 - 16 °C  
Polychaeta Polychaeta Spiophanes kroyeri Greenland Svalbard and Jan Mayen Ballast water Ballast water -0.9 - 17.2 °C  
Group Scientific Name

Ampelisca abdita

Amphipoda Caprella mutica
Amphipoda Crassicorophium bonellii
Amphipoda Gammarus cf. tigrinus
Amphipoda Gammarus cf. zaddachi
Amphipoda Gammarus daiberi
Amphipoda Grandidierella japonica
Amphipoda Jassa marmorata
Amphipoda Monocorophium acherusicum
Amphipoda Sinocorophium heteroceratum
Bryozoa Schizoporella unicornis
Cirripedia Amphibalanus amphitrite
Cirripedia Amphibalanus eburneus
Cirripedia Amphibalanus improvisus
Cirripedia Amphibalanus reticulatus
Cirripedia Austrominius modestus
Cirripedia Balanus trigonus
Cirripedia Conchoderma virgatum
Cirripedia Megabalanus cf. spinosus
Cirripedia Megabalanus cf. tintinnabulum
Cirripedia Megabalanus coccopoma
Cladocera Acantholeberis curvirostris
Cladocera Evadne nordmanni
Cladocera Podon leuckartii
Copepoda Acartia clausii
Copepoda Acartia tonsa
Copepoda Acartiella sinensis
Copepoda Anomalocera patersoni
Copepoda Calanus helgolandicus
Copepoda Centropages hamatus
Copepoda Centropages typicus
Copepoda Clausocalanus furcatus
Copepoda Cyclops kolensis kolensis
Copepoda Eurytemora affinis
Copepoda Euterpina acutifrons
Copepoda Heterolaophonte stroemii stroemii
Copepoda Isias clavipes
Copepoda Limnoithona tetraspina
Copepoda Metridia lucens
Copepoda Nitocra lacustris
Copepoda Oithona davisae
Copepoda Oithona similis
Copepoda Parapontella brevicornis
Copepoda Paronychocamptus huntsmani
Copepoda Pseudocalanus
Copepoda Pseudodiaptomus forbesi
Copepoda Pseudodiaptomus marinus
Copepoda Schizopera clandestina
Copepoda Sinocalanus doerrii
Copepoda Temora longicornis
Copepoda Temora turbinata
Copepoda Tortanus dextrilobatus
Decapoda Cancer irroratus
Decapoda Cancer pagurus
Decapoda Carcinus maenas
Decapoda Chionoecetes opilio
Decapoda Crangon crangon
Decapoda Hemigrapsus takanoi
Decapoda Paralithodes camtschaticus
Fish Acanthogobius flavimanus
Fish Dallia pectoralis
Fish Esox lucius
Fish Oncorhynchus mykiss
Fish Platichthys flesus
Fish Salvelinus fontinalis
Foraminiferan Trochammina hadai
Hydroid Garveia franciscana
Isopoda Eurydice pulchra
Isopoda Idotea linearis
Macroalgae Bonnemaisonia hamifera
Macroalgae Caulacanthus ustulatus
Macroalgae Ceramium sinicola
Macroalgae Chroodactylon ornatum
Macroalgae Codium fragile
Macroalgae Dumontia contorta
Macroalgae Fucus cottonii
Macroalgae Fucus serratus
Macroalgae Microspongium globosum
Macroalgae Sargassum muticum
Mollusc Cerastoderma edule
Mollusc Mya arenaria
Mollusc Mytilus galloprovincialis
Mysida Hyperacanthomysis longirostris
Mysida Mesopodopsis slabberi
Nematoda Ascolaimus sp.
Nematoda Axonolaimidae
Nematoda Daptonema tenuispiculum
Nematoda Geomonhystera sp.
Nematoda Prochromadora orleji
Phytoplankton Heterosigma akashiwo
Phytoplankton Mediopyxis helysia
Phytoplankton Neodenticula seminae
Phytoplankton Stephanopyxis turris
Plant Cotula coronopifolia
Polychaeta Heteromastus filiformis
Polychaeta Scolelepis sp.
Polychaeta Spiophanes kroyeri
Sponge Cliona thoosina
Tunicata Botrylloides violaceus
Tunicata Botryllus schlosseri
Tunicata Ciona intestinalis


The following publication related to this challenge has been published: