Prescribed List of Invasive Non Indigenous Species to consider in FeAST
List of Invasive Non Indigenous Species to consider in FeAST, as agreed with the Marine Invasive Non-Native Species Working Group.
Scientific name
Didemnum vexillum
Common name
Carpet Sea-squirt
Status in Scotland
Present
Prevention priority species? (High risk)
Y
Potential impacts
Capable of forming very large colonies, and likely to have considerable effect on pre-existing sessile hard-surface communities through overgrowth interactions etc; may encrust submerged structures but may also affect sheltered shallow subtidal hard substrates;
Scientific name
Styela clava
Common name
Leathery sea squirt
Status in Scotland
Present
Prevention priority species? (High risk)
N
Potential impacts
A relatively large organism that can reach high densities, sometimes being the dominant species in shallow sheltered habitats. The species may have a negative effect on the abundance and habitat occupancy of other shallow-water suspension feeding sessile invertebrates.
Scientific name
Asterocarpa humilis
Common name
Compass sea squirt
Status in Scotland
Present
Prevention priority species? (High risk)
N
Potential impacts
May have a negative effect on the abundance and habitat occupancy of other shallow-water suspension feeding sessile invertebrates. However, it is not clear whether this would cause the local extinction of any species, and A. humilis is at present know only from artificial substrates in its introduced range.
Scientific name
Caprella mutica
Common name
Japanese skeleton shrimp
Status in Scotland
Present
Prevention priority species? (High risk)
N
Potential impacts
Aquarium observations suggest aggressive competitive behaviour, displacing native skeleton shrimps. Behaviour has not been observed in the wild, species recorded living in close proximity to native shrimps under the same environmental conditions, suggesting that similar situations may arise. The wider environmental implications have yet to be confirmed, but it is possible that it will have a significant impact on benthic communities.
Scientific name
Schizoporella japonica
Common name
Orange rippled bryozoan
Status in Scotland
Present
Prevention priority species? (High risk)
N
Potential impacts
This species is a competitor for space and is known to inhibit the growth of adjacent species. However it is a poor invader of previously occupied space.
Scientific name
Undaria pinnatifida
Common name
Japanese wakame
Status in Scotland
Present
Prevention priority species? (High risk)
N
Potential impacts
Likely to compete for space and resources with native species of kelp and other brown seaweeds. It may also compete with other epibenthic animals and seaweed; may dominate algal cover on rocky shores from low tide down to 15m.
Scientific name
Sargassum muticum
Common name
Wireweed
Status in Scotland
Present
Prevention priority species? (High risk)
N
Potential impacts
Potential to out-competes native species because it is fast growing and reproduces within the first year of life by self-fertilisation producing large numbers of offspring. Abundance has been correlated with reduction in diversity of native seaweeds and other species such as sea oak. Dense stands reduce light, increase sedimentation and alter temperature in rockpools.
Scientific name
Corella eumyota
Common name
Orange tipped sea squirt
Status in Scotland
Present
Prevention priority species? (High risk)
N
Potential impacts
Populations might have a negative effect on the abundance and habitat occupancy of other shallow-water suspension feeding sessile invertebrates. However, it is not clear whether this would cause the local extinction of any species.
Scientific name
Botrylloides violaceus
Common name
Orange sheath tunicate
Status in Scotland
Present
Prevention priority species? (High risk)
N
Potential impacts
Capable of forming very large colonies, and likely to have considerable effect on pre-existing sessile communities through overgrowth interactions etc. Might therefore have a negative effect on the abundance and habitat occupancy of other shallow-water suspension feeding sessile invertebrates.
Scientific name
Watersipora subatra
Common name
Red ripple bryozoan
Status in Scotland
Present
Prevention priority species? (High risk)
N
Potential impacts
Capable of forming very large colonies, and likely to have considerable effect on pre-existing sessile communities through space occupancy, overgrowth interactions etc. Can dominate fouling communities and influence their composition; relatively resistant to copper-based antifouling treatments.
Scientific name
Homarus americanus
Common name
American Lobster
Status in Scotland
Records
Prevention priority species? (High risk)
Y
Potential impacts
Larger, more aggressive, more fecund and inhabit a broader range of habitats than the European lobsters, and so could outcompete the native population. Competition for resources is a threat not only to native lobsters but to other environmentally and economically important species such as brown crabs.
Scientific name
Magallana gigas
Common name
Pacific oyster
Status in Scotland
Records
Prevention priority species? (High risk)
N
Potential impacts
May form dense layered oyster beds on coarse/hard substrates in estuaries which can alter the natural state of the ecosystem, posing a potential threat to native species and altering habitats; recently found growing outside culture areas in the Solway, however any potential risks are associated with increasing temperatures that may allow natural spawning and subsequent impacts.
Scientific name
Eriocheir sinensis
Common name
Chinese mitten crab
Status in Scotland
Records
Prevention priority species? (High risk)
Y
Potential impacts
Likely to impact native, benthic invertebrate populations in freshwater and marine systems, through predation and competition for space. May cause siltation of gravel runs used for spawning by salmon/trout.
Scientific name
Crepidula fornicata
Common name
Slipper limpet
Status in Scotland
Horizon
Prevention priority species? (High risk)
Y
Potential impacts
Spatial competition occurs when numerous stacks of slipper limpets prevent other seabed species from settling and through the deposition of faeces and sediments they reduce hard-surface habitat availability. Competition for food may occur with other filter feeding species, including certain bivalves. Attachment to species, including mussels and mobile species may lead to a reduction in survival, growth and reproduction of the host. On a large scale, slipper limpet stacks have been shown to disturb normal water flow, trapping fine suspended particles. Large numbers can also reduce drainage of oyster beds during ebb tides, disturbing oyster metabolism.
Scientific name
Rapana venosa
Common name
Veined rapa whelk
Status in Scotland
Horizon
Prevention priority species? (High risk)
Y
Potential impacts
Voracious predator that feeds on mussels and common cockles and potentially native oysters. It may also out-compete native whelks for food.
Scientific name
Hemigrapsus sanguineus
Common name
Asian Shore Crab
Status in Scotland
Horizon
Prevention priority species? (High risk)
N
Potential impacts
Significant reductions in common shore crab abundance and mussel density have been reported where the Asian shore crab has achieved high densities in mainland Europe, and similar effects across the broader community may be expected. Common shore crab is also reported to have been displaced by the Asian shore crab in rocky shore habitats.
Scientific name
Hemigrapsus takanoi
Common name
Brush-clawed shore crab
Status in Scotland
Horizon
Prevention priority species? (High risk)
N
Potential impacts
A drastic reduction in the number of juvenile native common shore crabs has been observed. May replace the common shore crab as the dominant and most abundant shore crab species. A similar impact on native crabs may occur were the brush-clawed shore crab to become established in GB.
Scientific name
Mnemiopsis leidyi
Common name
American comb jelly
Status in Scotland
Horizon
Prevention priority species? (High risk)
N
Potential impacts
Major predator of zooplankton, fish eggs and larvae. Following its introduction into the Black Sea a dramatic decrease in abundance of almost all prey species of pelagic fish and the disappearance of some zooplankton species was observed. These extreme impacts occurred in the absence of natural predators; when a predator of the sea walnut was also unintentionally introduced to the Black Sea, M. leidyi numbers decreased rapidly and the ecosystem began to recover.
Scientific name
Gracilaria vermiculophylla
Common name
Rough agar weed
Status in Scotland
Horizon
Prevention priority species? (High risk)
Y
Potential impacts
Inhibits the growth and survival of native algae through competition. Loose-lying populations have the potential to develop into dense mats, particularly in shallow bays, lagoons, harbours and estuaries. These mats can modify the habitat available for the benthic faunal community and bottom dwelling fish. Algal mats can also form physical barriers for settling larvae, decrease light intensity, increase the likelihood of anoxia and change water movement patterns, which in turn affects sedimentation rate and thus food availability for deposit feeders.
Scientific name
Ocenebra inornata
Common name
Japanese sting winkle /oyster drill
Status in Scotland
Horizon
Prevention priority species? (High risk)
Y
Potential impacts
Predator of bivalves, notably oysters in invaded range (France).
Scientific name
Schizoporella errata
Common name
A bryozoan
Status in Scotland
Horizon
Prevention priority species? (High risk)
Y
Potential impacts
A strong competitor for space and is known to inhibit the growth of adjacent species.
Scientific name
Theora lubrica
Common name
Window shell
Status in Scotland
Horizon
Prevention priority species? (High risk)
Y
Potential impacts
Occurs in soft, muddy subtidal or lower intertidal sediments, rich in organic matter. It is considered a pollution-indicator species, because of its frequent dominance in highly polluted sediments. Despite high fecundity and dominance in such environments, ecological impacts have not been reported so far for this species.
Scientific name
Megabalanus tintinnabulum
Common name
Sea tulip
Status in Scotland
Horizon
Prevention priority species? (High risk)
N
Potential impacts
May compete with other intertidal hard substrate organisms for space and also possibly with a variety of filter-feeders for food.
Scientific name
Megabalanus coccopoma
Common name
Titan acorn barnacle/ Large pink barnacle
Status in Scotland
Horizon
Prevention priority species? (High risk)
N
Potential impacts
May compete with other intertidal hard substrate organisms for space and also possibly with a variety of filter-feeders for food.
Scientific name
Celtodoryx ciocalyptoides
Common name
A sponge
Status in Scotland
Horizon
Prevention priority species? (High risk)
N
Potential impacts
Potential to smother bivalve stocks (wild or cultured) or compete with them for space and food.
Scientific name
Paralithodes camtschaticus
Common name
Red king crab
Status in Scotland
Horizon
Prevention priority species? (High risk)
N
Potential impacts
Impacts to native benthic fauna would likely be significant as the red king crab is a voracious, omnivorous, opportunistic feeder. In Norway it is reported that scallop beds and flatfish populations are being reduced due to predation by the red king crab.
