Red Alga Invasive Species Information
What Is Red Alga - (Grateloupia doryphora)?
Habitat: prefers to live in shallow, protected subtidal waters, and likes to attach itself to hard substrates. It can survive water temperatures between 4 and 28° C, and salinities between 12 and 52 parts per thousand.
Distribution in Ireland: Coastal Areas
Status: Unknown
Family name: Grateloupia
Reproduction: Spores develop giving rise to filaments and blades.
Red Alga - Grateloupia doryphora
How To Identify Red Alga?
Colour: Red, olive green, brown
Size: The ribbon-like blades of this seaweed can reach a size of 100 cm by 20 cm, but are usually much smaller.
Red alga prefers shallow, protected subtidal waters attaching itself to hard substrates.
Red Alga - Grateloupia doryphora ID Guide
Why Is Red Alga A Problem?
Where Red Aga co-exists, it usually out competes the other non-native species.
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It can invade the habitat of a native seaweed, Chondrus crispus, aka: "Irish Moss", and crowd it out. Irish moss is used commercially to manufacture carigeen, and also provides an important winter food source for local marine invertebrates.
Additionally, the long blades of Red Alga can shade out other local species of algae and prevent them from growing nearby.
European Communities (Birds and Natural Habitats) Regulations 2011 non-native invasive plant species A-Z (Updated 2017)
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There are currently 35 invasive plant species listed in the European Communities (Birds and Natural Habitats) Regulations (annex 2, Part 1)...
Click on a species from the following list to find out more regarding non-native species subject to restrictions under Regulations 49 and 50.
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American Skunk-Cabbage - Lysichiton americanus
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Brazilian Giant-Rhubarb - Gunnera manicata
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Broad-Leaved Rush - Juncus planifolius
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Cape Pondweed - Aponogeton distachyos
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Cord-Grasses - Spartina (all species and hybrids)
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Curly Waterweed - Lagarosiphon major
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Dwarf Eel-Grass - Zostera japonica
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Fanwort - Cabomba caroliniana
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Floating Pennywort - Hydrocotyle ranunculoides
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Fringed Water-Lily - Nymphoides peltata
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Giant Hogweed - Heracleum mantegazzianum
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Giant Knotweed - Fallopia sachalinensis
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Giant-Rhubarb - Gunnera tinctoria
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Giant Salvinia - Salvinia molesta
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Himalayan Balsam - Impatiens glandulifera
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Himalayan Knotweed - Persicaria wallichii
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Hottentot-Fig - Carpobrotus edulis
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Japanese Knotweed - Fallopia japonica
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Large-Flowered Waterweed - Egeria densa
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Mile-a-Minute Weed - Persicaria perfoliata
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New Zealand Pigmyweed - Crassula helmsii
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Parrots Feather - Myriophyllum aquaticum
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Red Alga - Grateloupia doryphora
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Rhododendron - Rhododendron ponticum
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Salmonberry - Rubus spectabilis
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Sea-Buckthorn - Hippophae rhamnoides
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Spanish Bluebell - Hyacinthoides hispanica
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Three-Cornered Leek - Allium triquetrum
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Wakame - Undaria pinnatifida
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Water Chestnut - Trapa natans
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Water Fern - Azolla filiculoides
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Water Lettuce - Pistia stratiotes
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Water-Primrose - Ludwigia (all species)
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Waterweeds - Elodea (all species)
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Wireweed - Sargassum muticum