Duvaucelia plebeia

Invasion History

First Non-native North American Tidal Record: 1983
First Non-native West Coast Tidal Record:
First Non-native East/Gulf Coast Tidal Record: 1983

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General Invasion History:

Duvaucelia plebeia iis native to the Eastern Atlantic from Trondheim, Norway, south to Portugal and Spain. It is also found in the western Mediterranean and possibly the Aegean Sea. It feeds on the soft coral Alcyonium digitatum (Thompson and Brown 1984; Evertsen and Bakken 2005; Picton and Morrow 2010; de Kluijver et al. 2014). In 1983, D. plebeia was discovered on subtidal rock walls off Nahant, Massachusetts, feeding on Alcyonium sidereum. In 1985, it reached high abundances, but then declined in 1986 (Allmon and Sebens 1988). Recently, specimens have been seen elsewhere in the Gulf of Maine, but its current distribution and abundance are unknown (James Carlton, personal communication 2012; http://todivetoday.com/nudibranchs-of-north-east/).

North American Invasion History:

Invasion History on the East Coast:

Duvaucelia plebeia was first seen in the spring of 1983, during a long-term study of subtidal rock-walls off East Point, Nahant, Massachusetts, in Massachusetts Bay, Gulf of Maine. These rock walls had a diverse community of sponges, hydroids, tunicates, and the soft coral Alcyonium sidereum. Duvauceliaplebeia reached high abundances, drastically reducing the presence of the coral. The nudibranchs declined significantly in 1986, but the community effects from their predation persisted for several years thereafter (Allmon and Sebens 1988). Recently, specimens have been seen elsewhere in the Gulf of Maine, but its current distribution and abundance are unknown (James Carlton, personal communication 2012; http://todivetoday.com/nudibranchs-of-north-east/). 'Boom-and-bust' population dynamics appear to be common among nudibranchs, due to effects on their prey and their prey's competitors in the fouling community (Willan 1976; Chester et al. 2000). 

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Description

Duvaucelia plebeia has a slender body and an expanded head. The oral veil is produced into 2-4 pairs of finger-like pallial tentacles (or processes) extending outward from the anterior margin, with the number of tentacles increasing with the animals' size. The rhinophores resemble inverted cones, made of many thin plates (lamellae) emerging from wide basal sheaths. Gills may be absent in juveniles up to 3 mm long. There are 3-6 pairs of arborescent gills, increasing in number with body size, from three pairs at 4 mm to six pairs at 16 mm. Duvaucelia plebeia can reach 30 mm in size, but usually does not exceed 20 mm. The color is a pale yellow, with extensive greenish brown mottling. In Europe, darker individuals are usually found on yellow specimens of the soft coral Alcyonium digitatum while lighter D.plebeia are often found on white A. digitatum. Description based on Thompson and Brown (1984), Picton and Morrow (2010), and de Kluijver et al. (2014).

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Taxonomy

Ecology

General:

Duvaucelia plebeia i is a nudibranch which inhabits rocky coastal environments. Nudibranchs are simultaneous hermaphrodites and copulate reciprocally or unilaterally (Barnes 1983). Duvaucelia plebeia i lays its eggs in spiral ribbon-shaped masses attached to the base of Alcyonium spp. (soft-coral) (Brown and Thompson 1984; Picton and Morrow 2010). Tritonia plebia hatch into planktotrophic larvae (Todd and Doyle 1981).

Duvaucelia plebeia i inhabits subtidal rocky coasts, in areas of clear, cool water, on boulders and rock walls inhabited by soft-corals of the genus Alcyonium (Brown and Thompson 1984; Allmon and Sebens 1988; Picton and Morrow 2010). Its temperature and salinity requirements are unknown, but it probably has limited tolerance of high temperatures and low salinities. Duvaucelia plebeia i feeds on soft corals of the genus Alcyonium (Brown and Thompson 1984; Allmon and Sebens 1988).

Food:

Soft corals (Alcyonium spp.)

Consumers:

Competitors:

nudibranch Coryphella verrucosa

Trophic Status:

Carnivore

Carn

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Habitats

General Habitat	Rocky	None
Salinity Range	Polyhaline	18-30 PSU
Salinity Range	Euhaline	30-40 PSU
Tidal Range	Subtidal	None
Vertical Habitat	Epibenthic	None

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Life History

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Tolerances and Life History Parameters

Maximum Length (mm)	30	Rarely over 20 mm (Thompson and Brown 1984)
Broad Temperature Range	None	Cold temperate-Warm temperate
Broad Salinity Range	None	Polyhaline-Euhaline

General Impacts

Duvaucelia plebeia appeared in the Gulf of Maine in 1983, and became briefly abundant, preying on and greatly reducing the abundance of the soft coral Alcyonium sidereum. The nudibranch then disappeared or dropped to undetectable abundance, but some of the effects on the composition of the rock-wall community persisted for several years (Allmon and Sebens 1988).

Ecological Impacts

Predation: During its brief peak of abundance, D. plebeia eliminated soft corals (Alcyonium siderium) from rock walls at several sites in the Gulf of Maine. Predation by the nudibranch facilitated further predation by sea urchins (Strongylocentrus droebachiensis) by opening up space, permitting urchins to move into the coral-dominated areas, and eating most of the remaining corals. These changes in community composition persisted for at least two years after the disappearance of T. plebeia (Allmon and Sebens 1988).

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Regional Impacts

N170	Massachusetts Bay		Ecological Impact	Predation
During its brief peak of abundance, T. plebeia eliminated soft corals (Alcyonium siderium) from rock walls at several sites. Predation by the nudibranch facilitated further predation by sea urchins (Strongylocentrus droebachiensis) by opening up space, permitting urchins to move into the coral-dominated areas and eat most of the remaining corals (Allmon and Sebens 1988).
NA-ET2	Bay of Fundy to Cape Cod		Ecological Impact	Predation
During its brief peak of abundance, T. plebeia eliminated soft corals (Alcyonium siderium) from rock walls at several sites. Predation by the nudibranch facilitated further predation by sea urchins (Strongylocentrus droebachiensis) by opening up space, permitting urchins to move into the coral-dominated areas and eat most of the remaining corals (Allmon and Sebens 1988).
MA	Massachusetts		Ecological Impact	Predation
During its brief peak of abundance, T. plebeia eliminated soft corals (Alcyonium siderium) from rock walls at several sites. Predation by the nudibranch facilitated further predation by sea urchins (Strongylocentrus droebachiensis) by opening up space, permitting urchins to move into the coral-dominated areas and eat most of the remaining corals (Allmon and Sebens 1988).

References

Allmon, R. A, Sebens, K. P. (1988) Feeding biology and ecological impact of the introduced nudibranch, Tritonia plebeia, New England, USA, Marine Biology 99(3): 375-385

Barnes, Robert D. (1983) Invertebrate Zoology, Saunders, Philadelphia. Pp. 883

Chester, Charles M.; Turner, Roy; Carle, Michael; Harris, Larry G. (2000) Life history of a nudibranch/hydroid association: A discrete event simulation, Veliger 43(4): 338-348

de Kluijver, M. H.; Ingalsuo, S. S.; de Bruyne, R. H. 2014 Marine species identification portal: Molluscs of the North Sea. <missing URL>



Evertsen, Jussi; Bakken, Torkild (2005) Nudibranch diversity (Gastropoda, Heterobranchia) along the coast of Norway, Fauna Norvegica Series A 25: 1-37

Fraser. C. McClean (1936) Some Japanese hydroids: Mostly new, Transactions of the Royal Society of Canada- Section V Biological Sciences 30: 49-53

Haag, E.; Dyson, K (2014) Trade-off between safety and feeding in the sea anemone Anthopleura aureoradiata, New Zealand Journal of Marine and Freshwater Research 48(4): 540-546
https://doi.org/10.1080/00288330.2014.915858

Picton, Bernard E.; Morrow, Christine C. 2010 Encyclopedia of marine life of Britain and Ireland. <missing URL>



Rudman, W. B. 1997-2016 Sea Slug Forum. http://www.seaslugforum.net/



Ruiz, Gregory M.; Geller, Jonathan (2018) Spatial and temporal analysis of marine invasions in California, Part II: Humboldt Bay, Marina del Re, Port Hueneme, and San Francisco Bay, Smithsonian Environmental Research Center & Moss Landing Laboratories, Edgewater MD, Moss Landing CA. Pp. <missing location>

Thompson, T. E.; Brown, G. H. (1984) <missing title>, Ray Society, London. Pp. <missing location>

Todd, Christopher; Doyle, Roger W. D (1981) Reproductive strategies of marine benthic invertebrates: A settlement-timing hypothesis, Marine Ecology Progress Series 4: 75-83

Willan, Richard C. (1976) The opisthobranch Thecacera pennigera in New Zealand, with a discussion of the genus., Veliger 18(4): 347-352

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