Date of the first record

The date of the first documented record of the species occurrence in a country/country region.
Date fields usage example:

Date to be specifiedDate FromDate To
Exact 198519851985
18th century17011800
before 1700 1700
after 20012001 

Environmental position

Environment(s) occupied by a species throughout its life cycle.

OPTIONS:

Biofouling. Assemblage of organisms on wetted artificial substrates.

Commensal. An organism in a symbiotic relationship, in which one benefits while the other is not adversely affected.

Demersal. Synonyms: hyperbenthic, benthopelagic, nektobenthic. An organism living at, in or near the bottom of the sea, but having the ability to swim.

Ectoparasite. A parasite living on the surface of its host.

Endoparasite. A parasite living within the organs or tissues of its host.

Epifaunal. Synonym: epibenthic. An animal inhabiting the surface of the seabed, submerged plants and animals.

Epilithic. An organism living on the surface of rock or other hard inorganic substrata.

Epiphytic. An organism living on the surface of a plant, non-parasitic.

Epizoic. An organism living on the surface of an animal, non-parasitic.

Infaunal. Synonym: endobenthic. An animal living within the seabed sediments.

Interstitial. An organism (< 1 mm) living in the spaces between sediment particles.

Lithotomous. An organism burrowing into rock.

Neustonic. An organism living on (epineuston) or under (hyponeuston) the surface film of water bodies.

Pelagic. An organism inhabiting the water column.

Pleustonic. An organism inhabiting the water surface due to their own buoyancy, normally positioned partly in the water and partly in the air.

Habitat type

Estuary. River mouth, transition zone between riverine and marine environments, subject to influences from both.

Lagoon. Shallow, enclosed water body separated from the sea by barrier islands, narrow spit or reefs.

Offshore. Areas located at least 50 nautical miles from the shore.

Open coast. A coast not sheltered from the sea.

Strait/Sound. Channels between the mainland and an island or between two islands which are open at both ends to the open coast (it does not refer to similar features or narrows within marine inlets).

Sheltered coastal area. Coastal area partly surrounded by land (e.g., bay, inlet, fjord).

Ports. A location on a coast or shore containing one or more harbours where ships can dock and transfer people or cargo to or from land.

Port vicinity. The area near a port where ballast water operations may occur, including areas where vessels may conduct ballast water discharge or uptake operations when approaching a port or leaving it, e.g., port approaches, anchorage areas and designated ballast water exchange areas. The dimension is port specific.

Marina. A specially designed harbour for pleasure craft and small boats.

Aquaculture sites. Areas set out for the purpose of farming aquatic organisms.

Marine Protected Area (MPA). Defined marine area where natural resources are given greater protection than the surrounding waters. Different categories exist depending on the level of protection afforded by legislation.

Migration pattern

Diurnal. Movements between alternative habitats over day and night, e.g. vertical migration.

Life-time. One time migration between different habitats during the life cycle, e.g. anadromus migration.

Not relevant. No evidence of any life history cycle stages to migrate.

Seasonal. Movements between alternative habitats during a specific time of a year (e.g., spawning and feeding migrations).

Pathway / Vector

Pathway

A pathway is the route a NIS takes to enter or spread through a non-native ecosystem e.g. vessels. Each pathway may have a number of vectors.

Vector

A vector is a transfer mechanism and is the physical means by which species are transported from one geographic region to another. More than one vector within a pathway may be involved in a transfer of species.

Pathways and vectors included:
PathwayVector
Aquarium tradeIntentional organism release
Transported water
Waste discharge
Culture activitiesAquaculture equipment
Associated water & packaging material
Intercontinental stock movement
Regional stock movement
Unintentional release & escapees
Leisure activitiesAngling catch
Cultural releases
Live bait
Live souvenirs
Sport equipment
Stocking for angling
Waste discharge
Live food tradeIntentional organism release
Transported water
Waste discharge
ManagementBiological habitat management
Construction equipment
Construction materials
Release for biological control
Natural spread from neighboring countriesOther natural vectors
Water currents
Other canalsCanal de Midi (linking the Bay of Biscay with the Mediterranean Sea)
Kiel Canal (linking the North Sea with the Baltic)
Northern waterway (linking the Baltic with the Ponto-Caspian region through Volga river canal system)
Rhone waterway (linking the North Sea with the Mediterranean)
Southern waterway (linking the North Sea with the Black Sea through Danube river canal system)
Central waterway (linking the Baltic Sea with the Black Sea through the Dnieper river canal system)
Other waterways
Irrigation canals
Research and educationGear movement
Intentional releases
Unintentional release & escapees
Waste discharge
Suez Canal 
VesselsAnchor and anchor chain
Ballast tank sediments
Ballast water
Ship’s hull
Sea chest
Others
Wild fisheriesDiscard of by-catch
Fishing gear
Live bait release
Live packaging material
Processed live material
Stock movements
Transported water

Pathway / Vector – Levels of certainty:
LevelCriteriaExamples
Direct evidenceThe species was actually found associated with the specific vector(s) of a pathway at the time of introduction to a particular locality within a country/country region.Documented evidence of an introduction: release to the wild for stocking or biological control; escape/release of live food; import of cultured species and documented findings of their associate organisms, parasites and diseases on transmission; appearance of organisms by hull fouling, ballast water discharge sampling or other ship vectors documented upon an arrival with appropriate scientific methods.
Very likelyThe species appears for the first time in a locality where a single pathway/vector(s) is known to operate and where there is no other explanation that can be argued for its presence except by this likely pathway/vector(s).A highly localized distribution of a species in an area adjacent to an isolated port or other locality where the only pathway is vessels and its vector(s) (ballast water, hull fouling, etc). This often involves geographically discontinuous distributions. It may be a continuous spread as in case of introduction by canals or by natural means. The conclusion is deduced from the analysis of the invasion event and species distribution patterns.
PossibleThe species cannot be convincingly ascribed to a single pathway, but is known to be introduced by this pathway(s) elsewhere.There may be more than one pathway involved in the introduction within a country/country region. Arrival of a species known to have taken place elsewhere by the same pathway(s) which operates in an area. A conclusion is made by expert judgment based on pathways currently or historically present.
UnknownInvasion of a given alien species cannot be clearly explained.Where no rational explanation for the appearance of a species in a given country/region.

Population status

Population status (the lowest level of certainty):

Unknown. There is no reliable information on population status of a species.
Established. A species is known to form a reproducing population in a wild.
Not established. There is no evidence of a species’ reproducing population in a wild.

Population status (the moderate level of certainty):
Extinct/no recent record. There are old records where a species was recorded but have not been seen in the same region since.
Rare/single record. There are only casual observations or a single record of a species'presence available.
Common. A species with successfully reproducing populations in an open ecosystem, which are unlikely to be eliminated by man or natural causes. Not dominating native communities.
Abundant. A species with successfully reproducing populations in an open ecosystem, which are unlikely to be eliminated by man or natural causes. Locally dominating native communities.
Very abundant. A species with successfully reproducing populations in an open ecosystem, which are unlikely to be eliminated by man or natural causes. Largely dominating native communities.
Outbreak. A species undergoing pulse-like, short-term (days to few months) exponential population growth during which they have an adverse effect on one or more of the following: biological diversity, ecosystem functioning, socio-economic values and human health.

Recipient region

The country/region for which introduction is recorded.

References.



References should follow the standard of Biological invasions:


Journal article
Gamelin FX, Baquet G, Berthoin S, Thevenet D, Nourry C, Nottin S, Bosquet L (2009) Effect of high intensity intermittent training on heart rate variability in prepubescent children. Eur J Appl Physiol 105:731-738. doi: 10.1007/s00421-008-0955-8
Ideally, the names of all authors should be provided, but the usage of “et al” in long author lists will also be accepted:
Smith J, Jones M Jr, Houghton L et al (1999) Future of health insurance. N Engl J Med 965:325–329


Article by DOI


Slifka MK, Whitton JL (2000) Clinical implications of dysregulated cytokine production. J Mol Med. doi:10.1007/s001090000086


Book
South J, Blass B (2001) The future of modern genomics. Blackwell, London


Book chapter
Brown B, Aaron M (2001) The politics of nature. In: Smith J (ed) The rise of modern genomics, 3rd edn. Wiley, New York, pp 230-257


Online document
Cartwright J (2007) Big stars have weather too. IOP Publishing PhysicsWeb. http://physicsweb.org/articles/news/11/6/16/1. Accessed 26 June 2007


Dissertation
Trent JW (1975) Experimental acute renal failure. Dissertation, University of California

Reproductive duration

Long. Breeds in one or more discrete periods, each longer than three months.

Medium. Breeds in one or more discrete periods, each longer than a week and less than three months.

Short. Breeds in one or more discrete periods within a week.

Reproductive seasonality

Months for a species known to reproduce in the invaded site.

Salinity range

The exact salinity range if known (psu), else salinity zone(s) according to the Venice system:
1. Limnetic [<0.5psu]
2. β-Oligohaline [0.5-3psu]
3. α-Oligohaline [3-5psu]
4. β-Mesohaline [5-10psu]
5. α-Mesohaline [10-18psu]
6. Polymixohaline [18-30psu]
7. Euhaline [30-40psu]
8. Hypersaline [>40psu]

Source region

The area the species was introduced from to the recipient country/country region. Depending on the information availability may be ascribed to a particular locality (e.g. port), a country, a LME or a larger Ocean region.
CAUTION: in many cases the source area will be not the same as the area of native origin which is defined in the SPECIES block of the database.

Species status

Non-indigenous species. Non-indigenous species (synonyms: alien, exotic, non-native, allochthonous, introduced) are species, subspecies or lower taxa (such as a variety, form) introduced outside of their natural range (past or present) and outside of their natural dispersal potential. This includes any propagule of a NIS, such as a gamete, seed or resting spore, a gravid female or a pair of individuals of different sexes (in sexual reproduction), or a vegetative reproductive organ and section of tissue (in asexual reproduction), which might survive, reproduce and subsequently form a population. It also includes hybrids between an alien species and an indigenous species, fertile polyploid organisms and artificially hybridized species irrespective of their natural range or dispersal potential.

Cryptogenic. Cryptogenic species are such species which cannot be reliably demonstrated as being either introduced or native. In some cases the true origin of a species remains obscure because of either insufficient taxonomic knowledge or due to a lack of records from the time they became introduced, or for other reasons.

Temperature range

Indicate min. and max. annual temperature range in the area where a species is known to maintain an established (reproducing) population.

Wave exposure

Exposed. Open coastline facing prevailing wind and receiving both wind-driven waves and swell.

Semi exposed. Generally open coasts facing away from prevailing winds or sheltered by offshore reefs/structures.

Sheltered. Coasts with a restricted fetch (<20 km) and lacking persistent swell.

Zonation

Ecological zone(s) occupied by a species throughout its life cycle.

Benthic - Bathyal. Synonym: continental slope. The seafloor between the edge of the continental shelf and abyssal plain (200-4000 m).

Benthic - Littoral. Synonym: intertidal. The shore between the high and low water marks.

Benthic - Sublittoral beyond photic zone. Synonym: lower circalittoral. The lower part of the continental shelf, where photosynthesis cannot take place.

Benthic - Sublittoral within photic zone. Synonyms: subtidal, infralittoral. The shallow part of sublittoral where photosynthesis can occur.

Benthic - Supralittoral. Synonyms: splash zone, spray zone, supratidal zone. The area above the spring high tide line, subject spray or splash.

Pelagic - Littoral. Water mass within littoral zone.

Pelagic - Neritic. Water mass above the continental shelf.

Pelagic - Offshore. Synonym: oceanic. Water mass beyond the continental shelf.

Public domain: Introduction event account

Species Styela clava  
Date of the first record (?) To 1998

References (not structured):
Carlisle DB (1954) Styela mammiculata n.sp., a new species of ascidian from the Plymouth area. Journal of the Marine Biological Association of the United Kingdom 33: 329-334
Minchin D and Duggan CB (1988) The distribution of the exotic ascidian, Styela clava Herdman, in Cork Harbour. Irish Naturalists’ Journal 22: 388-393

Comments:
It is well established in Kent, Essex and Norfolk and also is known in the Humber. It was first recorded in Britain from Plymouth where it was described as Styela mammiculata.
Recipient region (?) Country: United Kingdom (Britain)
LME: 22. North Sea

References (not structured):
Ashelby CW (2005) The occurrence and distribution of non-native fauna in Harwich Harbour and the Stour and Orwell estuaries, including new records of Caprella mutica Schurin 1935 and Bugula stolonifera Ryland 1960. Essex Naturalist 22: 103-116.

Comments:
First recorded from Harwich Town Quay and in south-east coast estuaries on the east coast of Britain.
Source region (?) Country: Korea, Republic of
--> LME: 50. Sea of Japan / East Sea
Country: Korea, Republic of
--> LME: 48. Yellow Sea; LME sub-region: Yellow Sea

References (not structured):
Millar RH (1960) The identity of the ascidians Styela mammiculata Carlisle and S. clava Herdman. Journal of the Marine Biological Association of the United Kingdom 39: 509-511
Pathway / Vector (?) Level of certainty: Highly likely

Pathway: Vessels
Vector: (Highly likely) Ship’s hull

References (not structured):
Minchin D and Duggan CB (1988) The distribution of the exotic ascidian, Styela clava Herdman, in Cork Harbour. Irish Naturalists’ Journal 22: 388-393.
Davis MH and Davis ME (2004b) The role of man-aided dispersal in the spread of the immigrant Styela clava Herdman, 1882. Journal of Marine Science and
Environment 1: 18-24.

Comments:
There is evidence of this species appearing on the hulls of commercial shipping and leisure craft. It has also been found associated with oysters that have been transmitted as stock between different biogeographic areas.
Habitat type (?) Aquaculture sites
Lagoon
Marina
Marine Protected Area (MPA)
Port vicinity
Ports
Sheltered coastal area

References (not structured):
Davis MH, Lützen J, Davis ME (2007) The spread of Styela clava Herdman, 1882 (Tunicata, Ascidiacea) in European waters. Aquatic Invasions, 2(4):378-390.

Comments:
It is a notable fouling species of man-made structures, of aquaculture equipment and on vessel hulls. It occurs in lagoon-type environments and sheltered environments. Its ability to attach to culture equipment forms a risk the species may become transferred elsewhere.
Wave exposure (?) Sheltered

References (not structured):
Clarke CL, Therriault TW (2007) Biological Synopsis of the Invasive Tunicate Styela clava (Herdman 1881). Canadian Manuscript Report of Fisheries and Aquatic Sciences 2807.

Comments:
Typically favours low wave-energy environments and sheltered embayments, including marinas and ports.
Salinity range (?) Venice system:
6. Polymixohaline [18-30psu]
7. Euhaline [30-40psu]

References (not structured):
Krone R, Wanke C, Schröder A (2007) A new record of Styela clava Herdman, 1882 (Urochordata, Ascidiacea) from the central German Bight. Aquatic Invasions 2 (4): 442-444.

Comments:
Tolerates salinity range between 20-32psu. Pulses of low salinity result can purge populations.
Temperature range (?) Min: -2
Max: 23

References (not structured):
Krone R, Wanke C, Schröder A (2007) A new record of Styela clava Herdman, 1882 (Urochordata, Ascidiacea) from the central German Bight. Aquatic Invasions 2 (4): 442-444.
Zonation / Substratum (?) Benthic and Pelagic:
Littoral (Benthic)
Sublittoral within photic zone
Substratum:
Artificial (manmade)
Biogenic (living or nonliving)
Hard (cobbles to bedrock)

References (not structured):
Ashelby CW (2005)The occurrence and distribution of non-native fauna in Harwich Harbour and the Stour and Orwell estuaries, including new records of Caprella mutica Schurin 1935 and Bugula stolonifera Ryland 1960. Essex Naturalist 22: 103-116.
Clarke CL,Therriault TW (2007)Biological Synopsis of the Invasive Tunicate Styela clava (Herdman 1881). Canadian Manuscript Report of Fisheries and Aquatic Sciences 2807.

Comments:
Typically found in the upper sublittoral zone typically from 15-25m depth. As a fouling species, it is common on rocks and pylons and can attach to concrete and cement, wood, vessel hulls and reefs. Also commonly inhabits permanently submerged floating surfaces, such as buoys and pontoons.
Reproductive duration (?)Medium

References (not structured):
Clarke CL, Therriault TW (2007) Biological Synopsis of the Invasive Tunicate Styela clava (Herdman 1881). Canadian Manuscript Report of Fisheries and Aquatic Sciences 2807.

Comments:
Spawning is temperature dependant and it is believed to only be able to spawn in waters above 15 - 16°C.
Reproductive seasonality (?) Jul.
Aug.
Sept.

References (not structured):
Lützen J and Sørensen V (1993) Ecology, reproduction and further spread of the immigrant East-Asiatic ascidian Styela clava Herdman in Danish waters. Flora og Fauna 99: 75-79.
Migration pattern (?) Not entered
Population status (?) Common (Moderate level of certainty)

References (not structured):
Ashelby CW (2005)The occurrence and distribution of non-native fauna in Harwich Harbour and the Stour and Orwell estuaries, including new records of Caprella mutica Schurin 1935 and Bugula stolonifera Ryland 1960. Essex Naturalist 22: 103-116.

Comments:
Highly localised within port regions and marinas in areas with leas than full salinity.
Species status (?) Non-indigenous species

Comments:
Native to the north-west Pacific.
Created byDan Minchin, 2013-03-15
Last update byElizabeth J. Cook, 2014-06-05
Contributors
Added by Dan Minchin, 2013-03-15
Edited by Dan Minchin, 2013-10-29
Edited by Elizabeth J. Cook, 2014-06-05

Copyright © 2012 onwards - Coastal Research and Planning Institute
Support: FP7-ENVIRONMENT VECTORS
OS Template