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 Crepidula fornicata  
Date of the first record (?) 1893

References (not structured):
Nunn JD, Holmes JMC (2008) A Catalogue of the Irish and British marine mollusca in the collections of the National Museum, Natural History 1835-2008.
http://www.habitas.org.uk/nmi_catalogue/index.html (accessed 20 October 2015).Minchin D, McGrath D, Duggan CB (1995) The slipper limpet Crepidula fornicata (L.) in Irish waters with a review of its occurrence in the north-east Atlantic. Journal of Conchcology, London, 35(5): 297-301.
Syke ER (1905) The molluscs and brachiopods of Ballinakill and Bofin Harbours, Co. Galwav, and the deep
water off the west and south-west coasts of Ireland. Annual Report for Fisheries,Ireland 1902-03, Part 2: 53-92.

Comments:
The first record is of a single specimen in the Natural History Museum Dublin from 1893 from Dublin Bay. At this time American oysters were being imported in barrels from the USA and some were relaid in Dublin Bay and this may account for the finding of the single specimen at this time. A decade later oysters from Essex were being used in growth trails in Ballinakill Bay. C. fornicata were noted in a 1902 consignment and were removed by Sykes.
Recipient region (?) Country: Ireland
LME: 24. Celtic-Biscay Shelf
LME sub-region: Celtic seas


References (not structured):
Minchin D, McGrath D, Duggan CB (1995) The slipper limpet Crepidula fornicata (L.) in Irish waters with a review of its occurrence in the north-east Atlantic. Journal of Conchcology, London, 35(5): 297-301.
Sykes,E. R. (1905) The molluscs and brachiopods of Ballinakill and Bofin Harbours, Co. Galwav, and the deep
water off the west and south-west coasts of Ireland. Annual Report for Fisheries,Ireland 1902-03, Part 2: 53-92.

Comments:
The 1893 specimen was from Portmarnock, Dublin Bay.
Source region (?) Not entered

References (not structured):
Minchin D, McGrath D, Duggan CB (1995) The slipper limpet Crepidula fornicata (L.) in Irish waters with a review of its occurrence in the north-east Atlantic. Journal of Conchcology, London, 35(5): 297-301.
Sykes ER (1905) The molluscs and brachiopods of Ballinakill and Bofin Harbours, Co. Galwav, and the deep
water off the west and south-west coasts of Ireland. Annual Report for Fisheries,Ireland 1902-03, Part 2: 53-92.

Comments:
The first record of slipper limpets in Ireland were probably imported with American oysters.
Pathway / Vector (?) Level of certainty: Direct evidence

Pathway: Culture activities
Vector: Regional stock movement

References (not structured):
Minchin D, McGrath D, Duggan CB (1995) The slipper limpet Crepidula fornicata (L.) in Irish waters with a review of its occurrence in the north-east Atlantic. Journal of Conchcology, London, 35(5): 297-301.
Sykes,E. R. (1905) The molluscs and brachiopods of Ballinakill and Bofin Harbours, Co. Galwav, and the deep
water off the west and south-west coasts of Ireland. Annual Report for Fisheries,Ireland 1902-03, Part 2: 53-92.
McNeill G, Nunn J, Minchin D (2010) The slipper limpet Crepidula fornicata Linnaeus, 1758 becomes established in Ireland. Aquatic Invasions 5 Supplement 1: S21-25.

Comments:
Several occurrences of slipper limpets occurred during the early to mid 1900s and all would appear to have been associated with imports of laying oysters. The most recent living population is most probably as a result of mussels originating from south Wales being dumped in the Bay following their refusal for sale.
Habitat type (?) Sheltered coastal area

References (not structured):
McNeill G, Nunn J, Minchin D (2010) The slipper limpet Crepidula fornicata Linnaeus, 1758 becomes established in Ireland. Aquatic Invasions 5 Supplement 1: S21-25.

Comments:
The only known existing population in Belfast lough occurs in a semi-sheltered coastal area.
Wave exposure (?) Semi exposed
Sheltered

References (not structured):
McNeill G, Nunn J, Minchin D (2010) The slipper limpet Crepidula fornicata Linnaeus, 1758 becomes established in Ireland. Aquatic Invasions 5 Supplement 1: S21-25.

Comments:
Generally all of the records were from sheltered environments but the recent and established population in Belfast lough is in a semi-exposed area of the bay.
Salinity range (?) Exact range: 19 - 37

References (not structured):
Walne PR (1956) The biology and distribution of the slipper limpet Crepidula fornicata in Essex Rivers. Fishery Investigations, Ministry of Agriculture, Fisheries and Food. Series II, 10(6):1-50.

Comments:
No doubt the tolerance is greater than that found in experiments by Walne (1956).
Temperature range (?) Unknown

References (not structured):
Walne PR (1956) The biology and distribution of the slipper limpet Crepidula fornicata in Essex Rivers. Fishery Investigations, Ministry of Agriculture, Fisheries and Food. Series II, 10(6):1-50.

Comments:
Limpets succumb at temperatures of -5 to -6 C and in cold winter periods mortalities of limpets on the lower shore were noted in Essex, Britain.
Zonation / Substratum (?) Benthic:
Littoral (Benthic)
Sublittoral beyond photic zone
Sublittoral within photic zone
Substratum:
Soft (mud to pebbles)

References (not structured):
McNeill G, Nunn J, Minchin D (2010) The slipper limpet Crepidula fornicata Linnaeus, 1758 becomes established in Ireland. Aquatic Invasions 5 Supplement 1: S21-25.

Comments:
The living Irish population was found at lowest tide levels to ~7m depth
Reproductive duration (?)Medium

References (not structured):
Walne PR (1956) The biology and distribution of the slipper limpet Crepidula fornicata in Essex Rivers. Fishery Investigations, Ministry of Agriculture, Fisheries and Food. Series II, 10(6):1-50.

Comments:
Males crawl over the bottom and are attracted to snails that have developed to females and attach to them. Such groups, known as 'chains' were present in the dredged samples indication the capability to reproduce in Belfast Lough.
Reproductive seasonality (?) Apr.
May
Jun.

References (not structured):
Walne PR (1956) The biology and distribution of the slipper limpet Crepidula fornicata in Essex Rivers. Fishery Investigations, Ministry of Agriculture, Fisheries and Food. Series II, 10(6):1-50.

Comments:
In Essex spawning takes place once temperatures attain 10C, this is usually towards the end of April in shallow bays
Migration pattern (?) Not entered
Population status (?) Common (Moderate level of certainty)

References (not structured):
McNeill G, Nunn J, Minchin D (2010) The slipper limpet Crepidula fornicata Linnaeus, 1758 becomes established in Ireland. Aquatic Invasions 5 Supplement 1: S21-25.
Minchin D, McGrath D, Duggan CB (1995) The slipper limpet Crepidula fornicata (L.) in Irish waters with a review of its occurrence in the north-east Atlantic. Journal of Conchcology, London, 35(5): 297-301.
Minchin D, Nunn J (2006) Further range extensions of the marine gastropod Calyptraea chinensis (L.) in Ireland. Irish Naturalists’ Journal. 28 (5): 200-203.
Nunn JD, Holmes JMC (2008) A Catalogue of the Irish and British marine mollusca in the collections of the National Museum, Natural History 1835-2008.
http://www.habitas.org.uk/nmi_catalogue/index.html (accessed 20 October 2015).
Arnold DC 1960. Occurrence of the slipper limpet, Crcpidula fornicata L. in Ireland. Nature 196: 95.
Spicer JI (1923) The slipper limpet, an enemy of the oyster. Fish. Tech. Rep., Dublin 4pp.

Comments:
The recently found living population in Belfast Lough is established and is likely to be spread. It is the only surviving population in Ireland at present (2013). All previous records are of shells or populations that have expired and include the records of Arnold (1960)from Kilmakilloge Harbour, Kenmare Bay. Previously there have been accounts of the slipper limpet in Ireland dating from the import of Crassostrea virginica in 1902 (Sykes, 1905), all of which were presumably removed. From 1915 specimens were collected at Omeath, Carlingford Lough and were lodged in the Natural History Museum, Dublin. Such was the concern in these early years that leaflet was produced to advice upon the risks of the species becoming introduced and being vigilant in their disposal when dredged with oysters. A population was found in Clew Bay and in the 1963 study of the oyster beds, following the severe winter, no living slipper limpets or their shells were recovered (Minchin et al. 1995). Shells of limpets were recovered from Tralee Bay but these were in a consignment of autoclaved oyster shell used for laying in Tralee Bay as clutch for improving native oyster spat settlements.
During 2000 and 2001 consignments of Pacific oysters for culture, in Waterford Harbour in bags on trestles, had some small male specimens associated with consignments. A follow-up study failed to find any living after three months.
Species status (?) Non-indigenous species

References (not structured):
Abbott RT (1954) American Seashells, the New Illustrated Naturalist, D. Van Nostrand Co Inc., New York 541pp.

Comments:
In its native region it occurs from Canada to Texas.
Created byDan Minchin 
Last update byDan Minchin, 2013-11-05
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