BIOTIC Species Information for Ulva intestinalis
Researched byGeorgina Budd & Paolo Pizzola Data supplied byMarLIN
Refereed byThis information is not refereed.
General Biology
Growth formStraplike / Ribbonlike
Feeding methodPhotoautotroph
Mobility/MovementSee additional information
Permanent attachment
Environmental positionEpifloral
Typical food typesPhotoautotroph HabitAttached
BioturbatorNot relevant FlexibilityHigh (>45 degrees)
FragilityFragile SizeLarge(>50cm)
Height10 -30 cm. Growth Rate0.15-0.25 cm/day
Adult dispersal potentialNot relevant DependencyIndependent
General Biology Additional InformationGrowth rate
Parchevskij & Rabinovich (1991) cultivated Ulva intestinalis (as Enteromorpha intestinalis) on horizontally and vertically suspended ropes in coastal Black Sea areas polluted with sewage and waste water effluents. Specific growth rate of the seaweed during the spring-summer period was found to be 0.15-0.25 cm/day. A harvest weight of 2600-3000 g/m2 and 3400-4700 g/m2 was obtained within two weeks on horizontal and vertical ropes respectively.

Associated fauna
Ulva intestinalis provides shelter for the orange harpacticoid copepod, Tigriopus brevicornis, and the chironomid larva, Halocladius fucicola (McAllen, 1999). Ulva intestinalis is often the only seaweed found in supralittoral rockpools, and the copepod and chironomid species utilize the hollow thallus of Ulva intestinalis as a moist refuge from desiccation when the rockpools completely dry out. Several hundred individuals of Tigriopus brevicornis have been observed in a single thallus of Ulva intestinalis (McAllen, 1999). Many other intertidal species are often found amongst dense growths of Ulva in deep splash zone pools.

Floating masses
Ulva intestinalis may become detached from the substratum, and buoyed up by gas, float to the surface where they continue to grow. Such mats of unattached Ulva intestinalis are most frequent in summer. For instance, the occurrence of a summer mass of unattached Ulva intestinalis (as Enteromorpha intestinalis) was studied by Baeck et al. (2000) on the Finnish Baltic Sea west coast. The thalli of the seaweed lost their tubular shape, spread, and formed unattached monostromatic sheets. Mats were between 5-15 cm thick, with a biomass of 97 tonnes in an area of 3.7 km2 in 1993.
Biology References McAllen, 1999, Baeck et al., 2000, Parchevskij & Rabinovich, 1991, Clay, 1960b,
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