|Researched by||Dr Harvey Tyler-Walters||Refereed by||Dr Joanna Jones|
|Authority||(Hudson) J.V.Lamouroux, 1813|
|Other common names||-||Synonyms||-|
A conspicuous crimson seaweed up to 30 cm in length. Blades are oval or lanceolate, leaf like and reminiscent of beech leaves. The membranous lamina has a wavy margin and is supported by a conspicuous midrib with opposite pairs of lateral veins. The irregularly shaped, thickened holdfast (about 0.5 cm in diameter) gives rise to a short cylindrical stipe about 1 cm long. The stipe branches sparingly giving rise to spirally arranged blades (about 1.5 - 4 cm wide). The leaves may be pointed in young specimens. In autumn the membranous lamina is lost so that only the midrib remains. Reproductive bodies (e.g. cystocarp) develop on the naked midrib. Cystocarp are globular, with a membranous border, and form in fairly close formation on a short stalks on female plants. Carpogonia on female plants are fertilised during October but carpospores are not released until February. New fronds may grow before all reproductive structures disappear. Reproductive leaflets also grow on the denuded midrib in male and asexual plants. On the male plants tetrasporangial bladelets appear in November and tetraspores released in January and February [Kain & Bates, 1993]. Very wave battered plants may be confused with Phycodrys rubens (q.v.) which has lobed or toothed blades.
Young specimens may be confused with Apoglossum ruscifolium (q.v.) or Hypoglossum hypoglossoides (q.v.) although these species lack the conspicuous lateral veins of Delesseria sanguinea. Wave eroded (battered) specimens may resemble Phycodrys rubens. However, true Phycodrys rubens has lobed or toothed blades and reproductive structures are born on mature blades.
- none -
|Authority||(Hudson) J.V.Lamouroux, 1813|
|Typical abundance||Moderate density|
|Male size range|
|Male size at maturity|
|Female size range||Medium-large(21-50cm)|
|Female size at maturity|
|Growth rate||Insufficient information|
|Characteristic feeding method||Autotroph|
|Typically feeds on||Not relevant|
|Supports||No information found|
|Is the species harmful?||No|
Delesseria sanguinea is perennial and exhibits a complex life cycle. This species exhibits a strong seasonal pattern of growth and reproduction. New blades appear in February and grow to full size by May -June becoming increasing battered or torn and the lamina are reduced to midribs by December (Maggs & Hommersand, 1993). Blade weight is maximal in midsummer, growth dropping in June and July and becoming zero in August (Kain, 1984). Small new blades may be formed in darkness, reserves translocated from assimilates stored in the frond ribs and stipes which persist in winter (Luning, 1990; Maggs & Hommersand, 1993). Kain (1987) suggested that new blade growth may result from an increase in irradiance and hence inhibition of reproduction (e.g. due to removal of Laminarian plants from a kelp canopy) which may explain occasional crop of new blades noted in summer. Kain (1987) also suggested that the normal seasonal trigger for new blade production was temperature, probably when temperatures fell to 13 deg C or below. Morphology, salinity and temperature tolerances differ between North Sea and Baltic populations. In the Baltic specimens are smaller than British specimens, with thinner blades. Temperature and salinity tolerances are probably genetically determined (Rietema, 1993).
|Physiographic preferences||Strait / sound, Ria / Voe, Enclosed coast / Embayment|
|Biological zone preferences||Lower eulittoral, Sublittoral fringe, Upper infralittoral|
|Substratum / habitat preferences||Bedrock, Large to very large boulders, Rockpools, Small boulders|
|Tidal strength preferences||Moderately Strong 1 to 3 knots (0.5-1.5 m/sec.), Weak < 1 knot (<0.5 m/sec.)|
|Wave exposure preferences||Exposed, Extremely exposed, Moderately exposed, Very exposed|
|Salinity preferences||Full (30-40 psu), Reduced (18-30 psu), Variable (18-40 psu)|
|Other preferences||No text entered|
|Migration Pattern||Non-migratory / resident|
|Reproductive frequency||Annual episodic|
|Fecundity (number of eggs)||>1,000,000|
|Generation time||Insufficient information|
|Age at maturity||Insufficient information|
|Season||October - December|
|Life span||5-10 years|
|Larval/juvenile development||Spores (sexual / asexual)|
|Duration of larval stage||Not relevant|
|Larval dispersal potential||No information|
|Larval settlement period||Not relevant|
This MarLIN sensitivity assessment has been superseded by the MarESA approach to sensitivity assessment. MarLIN assessments used an approach that has now been modified to reflect the most recent conservation imperatives and terminology and are due to be updated by 2016/17.
|Delesseria sanguinea will be removed with the substratum and it is therefore highly intolerant. There is little information on recruitment or recolonization rates. Kain (1975) examined recolonization of cleared concrete blocks in a subtidal kelp forest. Red algae colonized blocks within 26 weeks in the shallow subtidal (0.8 m) and 33 weeks at 4.4 m. Delesseria sanguinea was noted within 41 weeks (8 months) at 4.4m in one group of blocks and within 56-59 days after block clearance in another group of blocks. This recolonization occurred during winter months following spore release and settlement, but not in subsequent samples (Kain, 1975). This suggests that recolonization of Delesseria sanguinea in new areas is directly dependent on spore availability. Rhodophyceae have non flagellate, and non-motile spores that stick on contact with the substratum. Norton (1992) noted that algal spore dispersal is probably determined by currents and turbulent deposition. However, red algae produce large numbers of spores that may settle close to the adult especially where currents are reduced by an algal turf or in kelp forests. It is likely that this species could recolonize an area from adjacent populations within a short period of time in ideal conditions but that recolonization from distant populations would probably take longer.|
|Adults are up to 30 cm in height and will probably survive smothering to a depth of 5 cm by sediment. However, algal spores and propagules are adversely affected by a layer of sediment, which can exclude up to 98 percent of light (Vadas et al., 1992). Germlings and juveniles are likely to be highly intolerant of smothering. A layer of sediment is likely to interfere with settlement and attachment of spores.|
|The effects of increased siltation on adults is likely to include smothering (above) or increase turbidity and therefore light attenuation (see below). Within kelp forest, current flows are reduced and siltation is likely to be increased. Therefore, Delesseria sanguinea may be tolerant of a level of siltation. Increased siltation may increase sediment scour, especially in winter. Spores, germlings and juveniles are likely to be highly intolerant of sediment scour (Vadas et al., 1992). However, Delesseria sanguinea reproduces in winter and increased siltation may interfere with recruitment and long term survival of the population.|
|Delesseria sanguinea is normally subtidal and unlikely to be exposed to desiccation except at extreme low tides or in exposed rock pools. Strong insolation of 20mW per square cm (comparable to mid day on a cloudless December in the UK) causes significant reduction in photosynthesis in only a few hours (1- 4 hrs) (Drew, 1983). A variety of subtidal red algae can survive aerial exposure for 14 hrs only at humidities of 100 percent (Kain & Norton, 1990). Spores and germlings are highly intolerant of desiccation due to there relatively high surface to area ratios. Subtidal algae are more intolerant of than intertidal algae to desiccation.|
|Delesseria sanguinea is a subtidal species. Increased emergence will extend tidal influence further down the shore. The extent of the population will be decreased accordingly by depressing its height up the shore as a result of increased desiccation, insolation and competition from intertidal algae. Similarly individuals inhabiting rock pools may be lost.|
|Algae are dependent on water flow for a supply of nutrients and removal of wastes. Delesseria sanguinea is found is a wide range of water flow regimes from moderately strong to weak. However, the flow rates experienced within kelp forests will be reduced. Deep growing red algae such as Delesseria sanguinea were observed growing in stagnating water in Kiel Bay, western Baltic Sea (Schwenke, 1960; cited in Kinne, 1971). It is likely, therefore, that this species would tolerate decreased water flow. However, an increase to strong or very strong may inhibit settlement of spores and may remove adults or germlings.|
|There is some evidence to suggest that blade growth in Delesseria sanguinea is delayed until ambient sea temperatures fall below 13 °C, although blade growth is likely to be intrinsically linked to gametangia development (see Kain, 1987). Delesseria sanguinea is tolerant of 23 deg C for a week (Lüning, 1984) but dies rapidly at 25 deg C. North Sea and Baltic specimens grew between 0-20 deg C, survived at 23 deg C but died at 25 deg C rapidly (Rietema, 1993). Rietema (1993) reported temperature differences in temperature tolerance between North Sea and Baltic specimens. Lüning (1990) reports optimal growth in Delesseria sanguinea between 10 - 15 deg C and optimal photosynthesis at 20 deg C. However, the upper limit of temperature tolerance is reduced by lowered salinity in Baltic specimens (Kinne, 1970; Kain & Norton, 1990). At low salinity photosynthesis is restricted to a narrow range of temperatures in adult thalli whereas juvenile thalli have a wider response range (Lobban & Harrison, 1997; fig 6.27). It is likely therefore that within the subtidal an increase in temperature of 2 deg C in the long term will have limited effect on survival, although it may affect initiation of new growth at the southern limits of the population. An increase of 5 deg C in the short term may affect survival if the ambient temperature is increased above 23 deg C.|
|Tolerant||Not relevant||Not sensitive||Moderate|
|Temperate, sub-tidal red algae are characterised by high rates of photosynthetic saturation, high maximum rates of photosynthesis and rapid growth. Reproduction in some species, triggered by short days, during winter when growth of other algae is limited, increased wave action results in loss of algae and most space is available for recolonization (Kain & Norton, 1990). Red algae possess only trace amounts of chlorophyll a (Lüning & Schmitz, 1988). Their main photosynthetic pigments are phycobiliproteins, which absorb optimally in the green light of deeper coastal waters. Photosynthesis in Delesseria sanguinea is inhibited by high light levels >200 µmol/m²/s, roughly equivalent to very clear shallow water in summer (Kain & Norton, 1990; Figure 15-2). However, in turbid coastal waters, where green light prevails, photosynthetic effectiveness increases with depth in red algae rich in phycoerythrin such as Delesseria sanguinea (Lüning, 1990). Delesseria sanguinea can grow in darkness using energy reserves stored in the stipe or lower regions of the frond ribs (Lüning, 1990). Increased turbidity would decrease the light levels at depth and may reduce the effective day length and induce reproduction earlier than in less turbid areas (Kain & Norton, 1990). Delesseria sanguinea is adapted to grow at depth or in the shade of other plants. Long term (years) decreased turbidity may restrict its downward extent. Short term changes may affect growth and reproduction, however, as a perennial, the adults will probably survive.|
|Tolerant||Not relevant||Not sensitive||Moderate|
|Delesseria sanguinea occurs on coasts with a wide range of wave exposures, from very exposed to very sheltered and are therefore unlikely to be intolerant of changes in wave action. The plants are sheltered from the worst effects of wave action by depth or dominant kelps.|
|Tolerant||Not relevant||Not sensitive||Not relevant|
|Plants have no known sound or vibration receptors|
|Tolerant||Not relevant||Not sensitive||Not relevant|
|Marine algae have no known response to visual stimuli.|
|Little information is available on the effects of abrasion on sub tidal red algae. However, the growth form of Delesseria sanguinea suggests that its lamina would probably be damaged by passing fishing gear, such as a scallop dredge (see benchmark). Although, its lamina is flexible a proportion of the population is likely to be torn off and lost. Specimens attached to cobbles or boulders may be removed (see substratum loss above). Therefore, an intolerance of intermediate has been recorded.|
|If Delesseria sanguinea is removed from the substratum it can not reattach itself and it is therefore highly intolerant. Kain (1975) examined recolonization of cleared concrete blocks in a subtidal kelp forest. Red algae colonized blocks within 26 weeks in the shallow subtidal (0.8 m) and 33 weeks at 4.4 m. Delesseria sanguinea was noted within 41 weeks (8 months) at 4.4 m in one group of blocks and within 56-59 days in blocks cleared at two monthly intervals during winter months, but not in subsequent samples (Kain, 1975). This suggests that Delesseria sanguinea can recolonize areas, but is directly dependent on its reproductive season and spore availability. Rhodophyceae have non flagellate, and non-motile spores that stick on contact with the substratum. Norton (1992) noted that algal spore dispersal is probably determined by currents and turbulent deposition. However, red algae produce large numbers of spores that may settle close to the adult especially where currents are reduced by an algal turf or in kelp forests. It is likely that this species could recolonize an area from adjacent populations within a short period of time in ideal conditions but that recolonization from distant populations would probably take longer.|
|O'Brien & Dixon (1976) suggested that red algae were the most sensitive group of algae to oil or dispersant contamination, possibly due to the susceptibility of phycoerythrins to destruction, and that the filamentous forms were the most sensitive. However, most evidence relates to dispersants. O'Brien & Dixon (1976) also report that red algae are effective indicators of detergent damage since they undergo colour changes when exposed to relatively low concentration of detergent. Smith (1968) reported that 10 ppm of the detergent BP 1002 killed the majority of specimens in 24hrs in toxicity tests. However, the effects take several days to manifest; when killed the lamina turn bright orange. Heavy mortality of Delesseria sanguinea occurred down to 12 m after the 'Torrey Canyon' oil spill (probably due to a mixture of wave action and dispersant application). Laboratory studies of the effects of oil and dispersants on several red algae species, including Delesseria sanguinea (Grandy, 1984; cited in Holt et al., 1995) concluded that they were all sensitive to oil/ dispersant mixtures, with little differences between adults, sporelings, diploid or haploid life stages. Cole et al. (1999) suggested that herbicides , such as simazina and atrazine were very toxic to macrophytes. Hoare & Hiscock (1974) noted that Delesseria sanguinea was excluded from Amlwch Bay, Anglesey by acidified halogenated effluent discharge. Holt et al. (1995) concluded that Delesseria sanguinea is probably generally sensitive to chemical contamination.|
|Low||Very high||Very Low||Low|
|Bryan (1984) suggested that the general order for heavy metal toxicity in seaweeds is: Organic Hg > inorganic Hg > Cu > Ag > Zn > Cd > Pb. Cole et al. (1999) reported that Hg was very toxic to macrophytes. The sub-lethal effects of Hg (organic and inorganic) on Plumaria elegans sporeling were reported by Boney (1971), for example 100 percent growth inhibition was caused by 1 ppm Hg in his study. However, little information concerning the effects of heavy metals on Delesseria sanguinea was found. Heavy metals have the potential to accumulate in plant tissue, therefore it may take some time for tissue levels to fall before recovery can begin.|
|Delesseria sanguinea is unlikely to become smothered by oil due to its subtidal position. However, O'Brien & Dixon (1976) suggested that red algae were the most sensitive group to oil or dispersant contamination, possibly due to the susceptibility of phycoerythrins to destruction, and that the filamentous forms were the most intolerant. Heavy mortality of Delesseria sanguinea occurred down to 12 m after the 'Torrey Canyon' oil spill, although it was unclear how much of the effect was due to oil rather than dispersant contamination. Laboratory studies of the effects of oil and dispersants on several red algae species, including Delesseria sanguinea (Grandy, 1984; cited in Holt et al., 1995) concluded that they were all sensitive to oil/ dispersant mixtures, with little differences between adults, sporelings, diploid or haploid life stages. Holt et al. (1995) concluded that Delesseria sanguinea is probably generally sensitive to chemical contamination.|
|No information||Not relevant||No information||Not relevant|
|Kain (1984) noted that growth of blades continued into July and August. Delesseria sanguinea can grow new blades in darkness by drawing on reserves held in frond midrib and stipe (Lüning, 1990), suggesting that nutrients are subject to 'luxury' accumulation in the winter months. Delesseria sanguinea is likely to tolerate low nutrient levels, during spring and summer. An increase in abundance of red algae, including Delesseria sanguinea, was associated with eutrophication in the Skagerrak area, Sweden, especially in areas with the most wave exposure or water exchange (Johansson et al., 1998). However, where eutrophication resulted in high siltation rates, the delicate foliose red algae such as Delesseria sanguinea were replaced by tougher, erect red algae (Johansson et al., 1998). High nutrient levels and eutrophication may result in increased siltation and turbidity (see above). Although increased nutrients may stimulate growth, this species may be out competed by green algae and epiphytes at the upper reaches of its range where light is less limiting.|
|Salinity and temperature affect photosynthesis. At low salinities photosynthesis in adults occurs in a restricted temperature range, although juvenile thalli photosynthesise across a wider range of temperatures (Lehnberg, 1978; cited in Lobban & Harrison, 1997). Rietema (1993) examined ecotypic differences between North Sea and Baltic populations of Delesseria sanguinea. Optimal growth occurred in Baltic specimens at 19 -23 psu and North Sea specimens at 33 psu. North Sea specimens died at 7.5 - 11 psu. Optimal photosynthesis occurred at full salinity, even in specimens collected from 15 psu (Lehnberg, 1978; cited in Lobban & Harrison, 1997). Increased salinity at 40 psu drastically reduced photosynthesis in Baltic specimens (Kinne, 1971). Delesseria sanguinea is likely to tolerate reduced salinity, although growth and reproduction may be reduced in low salinity environments when compared to full salinity.|
|The effects of deoxygenation in plants has been little studied. Since plants produce oxygen they may be considered relatively insensitive. However, a study of the effects of anaerobiosis (no oxygen) on some marine algae concluded that Delesseria sanguinea was very intolerant of anaerobic conditions; at 15 deg C death occurs within 24hrs and no recovery takes place although specimens survived at 5 deg C. (Hammer, 1972).|
|No information||No information||No information||Not relevant|
|No reference to diseases of red algae was found in the literature.|
|Not relevant||Not relevant||Not relevant||Not relevant|
|No non-native species were identified that compete with Delesseria sanguinea.|
|Not relevant||Not relevant||Not relevant||Not relevant|
|This species has been collected, by the French company GoËmar for cosmetic purposes, although knowledge of this trend continuing is unknown. Additionally sheep, on North Ronaldsay of the Orkneys have been known to graze on this species of algae.|
|Tolerant*||Not relevant||Not sensitive*||Low|
|Extraction or harvesting of kelp will increased light penetration and is likely to enhance growth. Kain (1975) showed that red algae recolonized cleared concrete blocks, in kelp forest in the Isle of Man; Delesseria sanguinea colonizing within 56-59 days. This suggests that extraction of kelp may encourage growth of this species in the short term until the kelp species dominate again.|
- no data -
|National (GB) importance||-||Global red list (IUCN) category||-|
Bold, H.C. & Wynne, M.J., 1978. Introduction to the algae: structure and reproduction. New-Jersey: Prentice-Hall, Inc.
Boney, A.D., 1971. Sub-lethal effects of mercury on marine algae. Marine Pollution Bulletin, 2, 69-71.
Dickinson, C.I., 1963. British seaweeds. London & Frome: Butler & Tanner Ltd.
Drew, E.A., 1983. Light. In Sublittoral ecology: The ecology of the shallow sublittoral benthos, (ed. R. Earll & D.G. Erwin). Oxford: Clarendon Press.
Guiry, M.D. & Blunden, G., 1991. Seaweed Resources in Europe: Uses and Potential. Chicester: John Wiley & Sons.
Hammer, L., 1972. Anaerobiosis in marine algae and marine phanerograms. In Proceedings of the Seventh International Seaweed Symposium, Sapporo, Japan, August 8-12, 1971 (ed. K. Nisizawa, S. Arasaki, Chihara, M., Hirose, H., Nakamura V., Tsuchiya, Y.), pp. 414-419. Tokyo: Tokyo University Press.
Hardy, F.G. & Guiry, M.D., 2003. A check-list and atlas of the seaweeds of Britain and Ireland. London: British Phycological Society
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Hoare, R. & Hiscock, K., 1974. An ecological survey of the rocky coast adjacent to the effluent of a bromine extraction plant. Estuarine and Coastal Marine Science, 2 (4), 329-348.
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Johansson ,G., Eriksson, B.K., Pedersen, M. & Snoeijs, P., 1998. Long term changes of macroalgal vegetation in the Skagerrak area. Hydrobiologia, 385, 121-138.
Kain, J.M., & Bates, M.J., 1993. The reproductive phenology of Delesseria sanguinea and Odonthalia dentata off the Isle of Man. European Journal of Phycology, 28, 173-182
Kain, J.M., & Norton, T.A., 1990. Marine Ecology. In Biology of the Red Algae, (ed. K.M. Cole & Sheath, R.G.). Cambridge: Cambridge University Press.
Kain, J.M., 1975a. Algal recolonization of some cleared subtidal areas. Journal of Ecology, 63, 739-765.
Kain, J.M., 1982. The reproductive phenology of nine species of the Rhodophycota in the subtidal region of the Isle of Man. British Phycological Journal, 17, 321-331.
Kain, J.M., 1987. Photoperiod and temperature as triggers in the seasonality of Delesseria sanguinea. Helgolander Meeresuntersuchungen, 41, 355-370.
Kain, J.M., 1991. The dithering males of Delesseria. British Phycological Journal, 26, 90.
Kain, J.M., 1996. Photoperiodism in Delesseria sanguinea (Ceramiales, Rhodophyta) 1. The phases and sexes differ. Phycologia, 35, 446-455.
Kinne, O. (ed.), 1970. Marine Ecology: A Comprehensive Treatise on Life in Oceans and Coastal Waters. Vol. 1 Environmental Factors Part 1. Chichester: John Wiley & Sons
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Kühl, H., 1981. The sand gaper Mya arenaria. In Invertebrates of the Wadden Sea. Final report of the section 'Marine Zoology' of the Wadden Sea Working Group, (ed. N. Dankers, H. Kuhl, W.J., Wolff), pp. 118-119.
Lobban, C.S. & Harrison, P.J., 1997. Seaweed ecology and physiology. Cambridge: Cambridge University Press.
Lüning, K., & Schmitz, K., 1988. Dark growth of the red algae Delesseria sanguinea, (Cerimales): lack of chlorophyll, photosynthetic capability, and phycobilisomes. Phycologia,27, 72-77
Lüning, K., 1984. Temperature tolerance and biogeography of seaweeds: the marine algal flora of Helgoland (North Sea) as an example. Helgolander Meeresuntersuchungen, 38, 305-317.
Maggs, C.A. & Hommersand, M.H., 1993. Seaweeds of the British Isles: Volume 1 Rhodophycota Part 3A Ceramiales. London: Natural History Museum, Her Majesty's Stationary Office.
Molenaar, F.J. & Breeman, A.M., 1997. Latitudinal trends in the growth and reproductive seasonality of Delesseria sanguinea, Membranoptera alata, and Phycodrys rubens (Rhodophyta). Journal of Phycology, 33, 330-343.
Norton, T.A. (ed.), 1985. Provisional Atlas of the Marine Algae of Britain and Ireland. Huntingdon: Biological Records Centre, Institute of Terrestrial Ecology.
Norton, T.A., 1992. Dispersal by macroalgae. British Phycological Journal, 27, 293-301.
Picton, B.E. & Costello, M.J., 1998. BioMar biotope viewer: a guide to marine habitats, fauna and flora of Britain and Ireland. [CD-ROM] Environmental Sciences Unit, Trinity College, Dublin.
Rietema, H., 1993. Ecotypic differences between Baltic and North Sea populations of Delesseria sanguinea and Membranoptera alata. Botanica Marina, 36, 15-21.
Smith, J.E. (ed.), 1968. 'Torrey Canyon'. Pollution and marine life. Cambridge: Cambridge University Press.
South, G.R. & Tittley, I., 1986. A Checklist and Distributional Index of the Benthic Marine Algae of the North Atlantic Ocean. London: British Museum (Natural History).
Vadas, R.L., Johnson, S. & Norton, T.A., 1992. Recruitment and mortality of early post-settlement stages of benthic algae. British Phycological Journal, 27, 331-351.
This review can be cited as:
Last Updated: 09/11/2006