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Mediterranean invasive species factsheet

Similar species Ecological impacts
There are no similar species in the Mediterranean No studies have yet quantified the ecosystem impact
Sea. In contrast to Aplysia, Bursatella leachii does of this species in the Mediterranean. The sporadic
not have large mantle flaps and cannot swim. Other high densities reported at some sites and its habit of
species, such as the endemic Tethys fimbria and the feeding on microalgal (cyanobacterial) mats may
genus Melibe, have large oral hoods (ceratas) used influence the dynamics of some natural habitats.
in the capture of food and a set of prominent cerata
(outgrowth structures) along each side of the body.
Economic impacts
In its native waters, ragged sea hares can reach very
high densities (more than 600 individuals per square
metre) and they are believed to adversely affect
commercial shrimping operations. Positive economic
impacts include the existence of a small aquarium
trade for this sea hare and the potential
pharmacological use of its ink gland.

Management options
A suggested prevention action is to conduct local
public awareness campaigns combined with
monitoring. A suggested control action is physical
Cerata
hand removal of new populations by MPA
technicians.

Further reading
Ibáñez-Yuste A., Garrido-Díaz A., Espinosa-Torre F.,
Terrón-Sigler A., 2012. Primera cita del molusco exótico
Bursatella leachii de Blainville, 1817 (Mollusca:
Melibe fimbriata. Photo: M. Draman opistobranchia) en el litoral mediterráneo andaluz.
Chronica naturae, 2: 25-31.
Zakhama-Sraieb, R., Ramzi S., Y Charfi- Cheirkhroucha,
F., 2009. On the occurrence of Bursatella leachii De
Brief history of its introduction and Blainville, 1817 and Pinctada radiata (Leach, 1814) in the
pathways Gar El Melh lagoon (NE Tunisia). Aquatic Invasions. Vol 4,
Issue 2:381-383
Originally found in warm temperate and tropical
http://www.ciesm.org/atlas/Bursatellaleachi.html
waters throughout the world, this species was
probably introduced into the Mediterranean through Tanrıkul, T. T.; Akyol, O., 2012. First report on reproduction
of Lessepsian ragged sea hare, Bursatella leachii (de
the Suez Canal, although ballast waters discharged
Blainville, 1817) (Mollusca: Gastropoda) in Izmir Bay
from cargo ships (water pumped into the ships
(Aegean Sea, Turkey). Journal of FisheriesSciences.com,
elsewhere as ballast to adjust buoyancy) could also Vol. 6 No. 2 pp. 96-98.
explain its occurrence in harbours. The first record of
the species in the Mediterranean Sea was in Israel
in 1940. Subsequently, the species was also
recorded from Turkey, Malta, Italy (Taranto, Sicily,
Lecce, Naples, Venice, Sardinia), Slovenia, Croatia
and around the Spanish coast, including the Balearic
Islands and Almería in the Alboran Sea. It has been
also reported in the Nador Lagoon (Morocco) and in Drawings: Juan Varela
other coastal lagoons and littoral areas around the
Mediterranean.

64 Monitoring Marine Invasive Species in Mediterranean MPAs: A strategy and practical guide for managers