Enteromorpha intestinalis

Description

Two similar species are found in Ireland, Enteromorpha compressa and  Enteromorpha intestinalis. Both are mid to bright green with a maximum length of 60 cm. Enteromorpha intestinalis is normally up to 7 cm wide, has a short stalk and long inflated, unbranched, tubular fronds with blunt ends.

Enteromorpha growing in rock pools at Spiddál, Co, Galway, Ireland

 The fronds of E. intestinalis are broader than E. compressa but are nipped in at irregular intervals along their length and swell with gas during growth. It has a discoid shaped holdfast. Enteromorpha intestinalis is remarkably tolerant of low salinities and can be found growing in full strength fresh water. Enteromorpha is normally free of fouling epiphytes due to a constant shedding of the top layer of its frond, hence retaining a clean appearance.   

  Enteromorpha compressa has long, narrow, compressed or inflated fronds, each of which has one or more branches, which in turn may have branchlets. Branches have blunt ends and are narrowest where they join the main frond. Both species are used for the same applications

Distribution

Close-up of Enteromorpha compressa

The genus Enteromorpha is extremely common consisting of very similar green seaweeds on all shore levels, found in bright green mats around the whole extent of the Irish coast, Europe and North America. Enteromorpha is present on a wide variety of substrate types including rocks, estuary mud banks, muddy sand flats, and in sheltered pools. It is commonly found in brackish areas, near fresh water inflows and in the splash zone above the high water mark. Quick growth occurs in winter and spring so that it forms a thick green carpet by early summer. Lengths often break off and float in intertidal pools or in the sea where inevitably they are cast up onto shores by the tide

Enteromorpha growing near a fresh water inlet at Kilmore Quay, Ireland 

Measuring Enteromorpha biomass using a quadrat on Tory Island, Ireland

Nutritional analysis