Distribution data supplied by the Ocean Biodiversity Information System (OBIS). To interrogate UK data visit the NBN Atlas.Map Help
Researched by | Dr Harvey Tyler-Walters & Paolo Pizzolla | Refereed by | Dr Stefan Kraan |
Authority | (Linnaeus) Lyngbye, 1819 | ||
Other common names | - | Synonyms | - |
A large sturdy brown alga 0.3 -1 m in length (occasionally up to 2 m) rising from a strong, flattened cone shaped holdfast. The main stem is flattened and branches alternately to give a distinctly zigzag appearance. The stem bears a few, flattened ribbon-like 'leafy' fronds. The ends of some branches bear characteristic pod-shaped air bladders (about 0.5 cm wide by 1-4 cm long) that are divided by transverse septa into 10 or 12 compartments. The branches also bear reproductive bodies that appear similar to the bladders but lack the septa. Young plants are olive-green in colour while older specimens are dark brown and leathery. This species is perennial.
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Phylum | Ochrophyta | Brown and yellow-green seaweeds |
Class | Phaeophyceae | |
Order | Fucales | |
Family | Sargassaceae | |
Genus | Halidrys | |
Authority | (Linnaeus) Lyngbye, 1819 | |
Recent Synonyms |
Typical abundance | See additional information | ||
Male size range | |||
Male size at maturity | |||
Female size range | Large(>50cm) | ||
Female size at maturity | |||
Growth form | Foliose | ||
Growth rate | Up to a maximum of 2cm/month | ||
Body flexibility | High (greater than 45 degrees) | ||
Mobility | |||
Characteristic feeding method | Autotroph | ||
Diet/food source | |||
Typically feeds on | |||
Sociability | |||
Environmental position | Epilithic | ||
Dependency | Independent. | ||
Supports | Substratum a number of epiphytic algae, hydroids, bryozoans and compound ascidians (Lewis, 1964; see additional information). | ||
Is the species harmful? | No information |
Although it is typically found in low abundances, Halidrys siliquosa can sometimes form beds (S. Kraan, pers. comm.). Growth rates
The growth rate of newly germinated Halidrys siliquosa (germlings) was found to be dependant on temperature, light intensity and day length. For example:
Moss & Lacey (1963) reported a maximum summer growth rate of 2 cm /month, although this figure was based on a single specimen.
Development
In shallow rock pools or surf affected populations the plants are frequently damaged resulting in a turf-like growth form due to a proliferation of branches from the damaged main axis (Moss & Lacey, 1963).
Seasonal changes
Moss & Lacey (1963) studied Northumberland populations of Halidrys siliquosa and reported:
In appears, therefore, that growth and development follows a seasonal cycle of allocation of energy towards growth in spring, followed by allocation to reproduction later in the year. However, Wernberg et al. (2001) did not detect any significant seasonal change in biomass in the Limfjord, Denmark, due to high monthly variation in biomass, although the specimens they examined were small. They did not detect any seasonal change in thallus height or percentage cover.
Epiphytes
Halidrys siliquosa has been reported to support a number of epiphytic species, depending on location, including microflora (e.g. bacteria, blue green algae, diatoms and juvenile larger algae), Ulothrix and Ceramium sp., hydroids (e.g. Laomedea flexuosa and Obelia spp.), bryozoans (e.g. Scrupocellaria spp.), and ascidians (e.g. Apilidium spp. and Botrylloides leachi ). However, Halidrys siliquosa was considered to be relatively clear of epiphytes due to its ability to shed the outer layer of epidermal cell walls, together with adherent epiphytes (Moss, 1982; Lobban & Harrison, 1997).
Physiographic preferences | Open coast, Strait / sound, Sea loch / Sea lough, Ria / Voe, Enclosed coast / Embayment |
Biological zone preferences | Lower eulittoral, Mid eulittoral, Sublittoral fringe, Upper infralittoral |
Substratum / habitat preferences | Bedrock, Cobbles, Large to very large boulders, Rockpools, Small boulders |
Tidal strength preferences | Moderately Strong 1 to 3 knots (0.5-1.5 m/sec.), Very Weak (negligible), Weak < 1 knot (<0.5 m/sec.) |
Wave exposure preferences | Exposed, Moderately exposed, Sheltered, Very sheltered |
Salinity preferences | Full (30-40 psu), Variable (18-40 psu) |
Depth range | Intertidal to 4 m |
Other preferences | No text entered |
Migration Pattern | Non-migratory / resident |
Reproductive type | Permanent (synchronous) hermaphrodite | |
Reproductive frequency | Annual episodic | |
Fecundity (number of eggs) | >1,000,000 | |
Generation time | 1-2 years | |
Age at maturity | 2 years | |
Season | December - March | |
Life span | Insufficient information |
Larval/propagule type | - |
Larval/juvenile development | Spores (sexual / asexual) |
Duration of larval stage | < 1 day |
Larval dispersal potential | See additional information |
Larval settlement period | Insufficient information |
The MarLIN sensitivity assessment approach used below has been superseded by the MarESA (Marine Evidence-based Sensitivity Assessment) approach (see menu). The MarLIN approach was used for assessments from 1999-2010. The MarESA approach reflects the recent conservation imperatives and terminology and is used for sensitivity assessments from 2014 onwards.
Intolerance | Recoverability | Sensitivity | Evidence/Confidence | |
High | High | Moderate | Low | |
Removal of the substratum will result in removal of adults and germlings of Halidrys siliquosa. Therefore, an intolerance of high has been recorded. Recoverability has been assessed as high (see additional information below). | ||||
Intermediate | High | Low | Low | |
Adult plants are large and held upright by their air bladders when immersed. Therefore, smothering by 5 cm of sediment is likely to only cover the base of the plant and have little effect. Intertidal rock pool populations may be more intolerant, depending on the depth of the pool. However, young (up to 1 year old) plants do not bear air bladders, and, together with germlings, are likely to be smothered by the sediment, preventing photosynthesis, and potentially kill young plants. Germlings can survive for up to 120 days in the dark (Moss & Sheader, 1973), so may not be affected by smothering for a month (see benchmark), although any resultant anoxic conditions would probably be detrimental. The presence of a layer sediment has been shown to cause stress and considerable mortality in algal propagules, and sediment scour in flowing water may also remove and kill zygotes or germlings (Vadas et al., 1992). Smothering by epiphytes (see general biology) may reduce photosynthesis and increase drag on the thallus increasing its susceptibility to storm damage. Epiphyte communities have been shown to reduce light reaching the plant and decrease the rates of oxygen exchange with the surrounding water. This is especially true in eutrophic conditions, the result being a reduction in photosynthesis and metabolic stress in macrophytes (Sand-Jensen et al., 1985, Phillipart, 1995b) which will presumably affect macroalgae similarly. Nevertheless, Halidrys siliquosa is able to shed its outer cell walls in order to reduce surface epiphytes (Moss, 1982). Overall, younger or smaller plants, together with germlings may be killed and recruitment reduced. Therefore, an intolerance of intermediate and a high recoverability has been recorded (see additional information). | ||||
Low | Very high | Very Low | Low | |
Increased suspended sediment concentrations will increase turbidity (see below). Suspended sediment settling on algal fronds is likely to reduce photosynthesis, and additional scour by sediment in water flow may adversely affect germling and reduce settlement. Halidrys siliquosa occurs in sheltered and very sheltered conditions, in which siltation rates may be high. Therefore, Halidrys siliquosa may tolerate suspended sediment and is unlikely to be significantly affected by an increase in suspended sediment concentrations for one month (see benchmark). Hence an intolerance of low has been recorded. Increased suspended sediment may reduce recruitment if it coincided with reproductive season. Recovery is likely to be rapid (see additional information below). | ||||
Tolerant | Not relevant | Not sensitive | Not relevant | |
A decrease in suspended sediment is unlikely to have any direct affects on Halidrys siliquosa, except to decrease turbidity (see below). | ||||
Intermediate | High | Low | Low | |
Halidrys siliquosa occurs subtidally, in the sublittoral fringe and is restricted to rockpools in the intertidal. Therefore, it is intolerant of desiccation. It is protected from exposure to desiccation in rockpools and subtidally, however, sublittoral fringe populations may be exposed to the air. Therefore, an increase in desiccation at the benchmark level is likely to adversely effect a proportion of the population and an intolerance of intermediate has been recorded. Recoverability has been assessed as high (see additional information below). | ||||
Intermediate | High | Low | Low | |
A one hour increase in emergence is likely to expose the upper portion of the population, especially in the sublittoral fringe, to desiccation, increased wave action and an increased range of temperature change. Halidrys siliquosa is restricted to rock pools in the intertidal, therefore increased emergence is likely to result in loss of the exposed plants, a loss of a proportion of the population. Hence, intolerance has been assessed as intermediate with recoverability of high (see additional information below). | ||||
Tolerant* | Not relevant | Not sensitive* | Low | |
Decreased emergence and hence, increased immersion may allow Halidrys siliquosa to colonize further up the shore. Therefore, the population may benefit overall. | ||||
High | High | Moderate | Low | |
Water flow is important to supply nutrients and oxygen, and water flow has been shown to increase photosynthesis in Halidrys siliquosa (Schwenke, 1971). Halidrys siliquosa was reported from the 'rapids approaches' in association with Himanthallia elongata and Saccharina latissima (studied as Laminaria saccharina), and may occur in association with Laminaria digitata in strongly flowing tidal streams (Lewis, 1964). Halidrys siliquosa decreases in abundance with increasing water flow, so that in tidal rapids with current speeds of 2-3m/sec (ca 6 knots), it is replaced by Laminaria digitata, Laminaria hyperborea and Saccorhiza polyschides communities (Lewis, 1964; Schwenke, 1971). An increase in water flow from, for example, weak to strong (see benchmark) it likely to significantly reduce the population within a year, resulting in its replacement by species tolerant of strong water flow. Therefore, an intolerance of high has been recorded with a recoverability of high (see additional information below). | ||||
Low | Immediate | Not sensitive | ||
Halidrys siliquosa occurs in moderately strong to weak tidal streams, as well as in rock pools, and is probably tolerant on stagnant water in the short term. Therefore a further decrease in water flow is unlikely to have an adverse effect. Reduced water flow may reduce oxygen and nutrient exchange, therefore an intolerance of low has been recorded. Recoverability will probably be immediate. | ||||
Tolerant | Not relevant | Not sensitive | Moderate | |
Lüning (1984, 1990) reported an upper survival temperature of 25 °C after one week exposure in Halidrys siliquosa. It did not survive at the higher temperatures studied. Zygote germination and growth are temperature dependant. Moss & Sheader (1973) reported 50-97% germination at 3 and 10 °C, falling considerably to 8 -52% at 20 °C and to zero at 22 °C. Growth increased with temperature up to 20 °C but germlings developed abnormally at 20 °C (Moss & Sheader, 1973). Halidrys siliquosa is distributed from northern Norway to northern Portugal and also occurs in rock pools, which may experience a relatively large temperature range. Therefore, it is unlikely to be affected by long term temperature changes within the British Isles. Short term acute change may have adverse effects if the change increased the temperature over 20-25°C, especially if the change coincided with the release of gametes or the germination of zygotes. However, Halidrys siliquosa releases gametes and zygotes in the winter months (December to March). Overall, Halidrys siliquosa is probably tolerant to changes of temperature in British waters. | ||||
Tolerant | Not relevant | Not sensitive | Low | |
Little information concerning the effects of low temperatures on Halidrys siliquosa was found. Lüning (1984, 1990) reported that it survived at 0 °C for one week, and Moss & Sheader (1973) reported that the lower limit of germination was not reached at 3 °C but that no gametes were released from fertile receptacles at -4 °C. Halidrys siliquosa is protected from ice scour or severe frosts by its subtidal or rock pool habit. Overall, Halidrys siliquosa is recorded from northern Norway and is probably tolerant to decreases of temperature likely to occur in British waters. | ||||
Intermediate | High | Low | Low | |
Increased turbidity decreases light penetration and hence decreases photosynthesis, plant growth and reproduction. Moss & Sheader (1973) demonstrated that the growth of germlings was dependent on light intensity but that germlings could survive total darkness for 120 days (see general biology). Halidrys siliquosa occurs in sheltered waters that may already be of medium to high turbidity (see benchmark), therefore an additional increase in turbidity may adversely effect the population. A short term increase may not have significant effects. An increase from medium to high turbidity for a year is likely to result in loss of the deepest extent of the population. Therefore, an intolerance of intermediate has been reported. Extreme turbidity for a year is likely to result in loss of macroalgae. Recoverability has been assessed as high (see additional information below). | ||||
Tolerant* | Not relevant | Not sensitive* | Low | |
Decreased turbidity and hence increased light penetration is likely to benefit all macroalgae present, and may allow the Halidrys siliquosa population to extend to greater depths. Moss & Sheader (1973) noted that Halidrys siliquosa germlings approached photosynthetic saturation at light intensities about 5 fold those of early sporophytes of Laminaria hyperborea, possibly an adaptation to exposure to high light intensities in rock pools. Therefore, the population is likely to benefit from decreased turbidity | ||||
High | High | Moderate | Moderate | |
Halidrys siliquosa is most abundant on sheltered shores but is found on wave exposed shores where it occurs, primarily in deep mid-shore pools (Lewis, 1964). Halidrys siliquosa develops as a short, stunted turf in wave exposed pools (Moss & Lacey, 1963; Lewis, 1964) suggesting that it can tolerate strong water movement (Lewis, 1964). However, with increasing wave exposure Halidrys siliquosa / Saccharina latissima (studied as Laminaria saccharina) communities are replaced by Laminaria digitata or Laminaria hyperborea communities (Lewis, 1964). Therefore, intolerance of high has been recorded with a recoverability of high (see additional information). | ||||
Tolerant* | Not relevant | Not sensitive* | Low | |
Halidrys siliquosa is associated with wave sheltered rocky substrata (Lewis, 1964). A decrease in wave exposure is likely to allow Halidrys siliquosa to colonize space and to increase in extent. Therefore, the population may benefit from a decrease in wave exposure. | ||||
Tolerant | Not relevant | Not sensitive | High | |
Macroalgae are not known to perceive noise of vibration. | ||||
Tolerant | Not relevant | Not sensitive | High | |
Although macroalgae respond to light, they have no visual perception. | ||||
Intermediate | High | Low | Low | |
Physical disturbance by a scallop dredge (see benchmark) may damage or remove some individuals. Therefore, an intolerance of intermediate has been recorded. Damaged individuals with intact holdfasts, i.e. not removed, will probably survive. | ||||
High | High | Moderate | Low | |
Halidrys siliquosa is permanently attached to the substratum and once removed would not be able to reattach. Therefore, displaced individuals would be lost and an intolerance of high has been recorded. Recoverability has been assessed as high (see additional information below). |
Intolerance | Recoverability | Sensitivity | Evidence/Confidence | |
Intermediate | High | Low | Very low | |
No information on the intolerance of Halidrys siliquosa to synthetic chemicals was found, however, information on other Fucales was available. Fucoids are generally quite robust in terms of chemical pollution (Holt et al., 1995, 1997), e.g. Fucus sp. seems to thrive in TBT-polluted waters (Bryan & Gibbs, 1991). However, Rosemarin et al. (1994) stated that brown algae (Phaeophyta) were extraordinarily highly sensitive to chlorate, such as from pulp mill or brine electrolysis effluents (Holt et al., 1997). In the Baltic, Fucus vesiculosus disappeared in the vicinity of pulp mill discharge points and was adversely affected even at immediate and remote distances (Kautsky, 1992). Different life stages of Fucus serratus differ in their intolerance to synthetic chemicals. Scalan & Wilkinson (1987) found that spermatozoa and newly fertilized eggs of Fucus serratus were the most intolerant of biocides, while adult plants were only just significantly affected at 5ml/l of the biocides Dodigen v181-1, Dodigen v 2861-1 and ML-910. Herbicides (e.g. Diuron and Linuron) in agricultural or urban runoff are likely to be highly toxic to algae (Cole et al., 1999). Therefore, given the reported intolerance of brown algae to chlorates, and their potential intolerance to biocides and herbicides, an intolerance of intermediate has been recorded albeit at very low confidence. Recoverability has been recorded as high (see additional information below). | ||||
Low | Very high | Very Low | Moderate | |
Holt et al., (1995, 1997) reported that fucoids and other algae were capable of retaining and concentrating heavy metals, so much so that Fucus spp. are used as indicators of heavy metal pollution. Alginates found in fucoids (and in Halidrys siliquosa) strip heavy metals and some radionuclides from seawater and store them in inert forms. Hence, adult plants are considered to be relatively tolerant of heavy metal contamination. however, younger stages may be more intolerant. for example iron ore dust interfered with the interaction between eggs and sperm in Fucus serratus (Boney, 1980; cited in Bryan, 1984). Bryan (1984) also reported that heavy metals retarded growth in brown algae, and suggested that heavy metal toxicities to seaweeds was in the order of Hg>Cu>Ag>Zn>Zn>Cd>Pb. Overall, it appears that members of the fucales, and by inference Halidrys siliquosa are relatively tolerant of heavy metal pollution and an intolerance of low has been recorded. | ||||
Low | Very high | Very Low | Low | |
Halidrys siliquosa is protected from the direct effects of oil spills due to its subtidal habit, although sublittoral fringe and rock pool populations will be more vulnerable. However, plants may be exposed to water soluble components of the oil or oil adsorbed on to particulates. No information concerning the effects of oil on Halidrys siliquosa was found. Holt et al. (1997) suggested that fucoids had limited intolerance to oil but noted that studies on long-term exposure were limited. For example, adult Fucus serratus plants are tolerant of exposure to spills of crude oil although very young germlings are intolerant of relatively low concentrations of 'water soluble' extractions of crude oils. Exposure of eggs to these extracts (at 1.5 micrograms/ml for 96 hours) interferes with adhesion during settling and at 0.1micrograms/ml) prevented further development (Johnston, 1977). Fucus vesiculosus showed limited intolerance to oil. After the Amoco Cadiz oil spill Fucus vesiculosus suffered very little (Floc'h & Diouris, 1980). Indeed, Fucus vesiculosus, may increase significantly in abundance on a shore where grazing gastropods have been killed by oil. However, very heavy fouling could reduce light available for photosynthesis and in Norway a heavy oil spill reduced fucoid cover. Therefore, it appears that fucoids, and by inference Halidrys siliquosa, have a limited intolerance to hydrocarbons and an intolerance of low has been recorded. | ||||
No information | Not relevant | No information | Not relevant | |
Ryan et al (2003) report on radioactivity levels in various fucoids around Ireland although no specific information was found on either Halidrys siliquosa or effects on fucoids in general. | ||||
Tolerant* | Not relevant | Not sensitive* | Moderate | |
Wernberg et al. (2001) reported that the N:P (nitrogen to phosphorus) ratio in Limfjorden Halidrys siliquosa was low in summer and high in spring, which suggested that growth was nutrient limited by P in spring and N in summer. Kindig & Littler (1980) exposed Halidrys dioica and other algae to 10% untreated sewage effluent in the field, which resulted in increased gross productivity. However, Halidrys dioica was found to be absent in the vicinity of a sewage outfall, and Kindig & Littler (1980) concluded that another component of the effluent, other than nutrient, was responsible. Overall, therefore, it would appear that moderate nutrient enrichment at the benchmark level may stimulate growth of Halidrys spp. However, excessive enrichment may lead to eutrophication, decreased oxygen levels (see below) and the potential smothering of Halidrys sp. by microfloral epiphytes (see smothering). | ||||
Low | Very high | Very Low | Very low | |
No information on salinity tolerance was found. However, Halidrys siliquosa occurs in rock pools, which may experience considerable fluctuations in salinity due to evaporation on hot days. Therefore, Halidrys siliquosa is probably tolerant of fluctuations in salinity, both increases and decreases, and an intolerance of low has been recorded. | ||||
Low | Very high | Very Low | ||
No information on salinity tolerance was found. However, Halidrys siliquosa occurs in rock pools, which may experience considerable decline in salinity due to freshwater influence during rain. Therefore, Halidrys siliquosa is probably tolerant of fluctuations in salinity, both increases and decreases, and an intolerance of low has been recorded. | ||||
No information | Not relevant | No information | Not relevant | |
Little information on the effects of oxygen depletion on macroalgae was found. Kinne (1972) reports that reduced oxygen concentrations inhibit both photosynthesis and respiration. The effects of decreased oxygen concentration equivalent to the benchmark would be greatest during dark when the macroalgae are dependant on respiration. |
Intolerance | Recoverability | Sensitivity | Evidence/Confidence | |
No information | Not relevant | No information | Not relevant | |
Halidrys siliquosa supports a number of epiphytic species, which use it as a substratum but are not parasitic on the plant. No information on diseases was found. | ||||
High | High | Moderate | High | |
Halidrys siliquosa has been reported to be displaced as the dominant species in rock pools by the non-native Sargassum muticum on the south coast of England (Eno et al., 1997). Staehr et al. (2000) reported that an increase in the abundance of Sargassum muticum in Limfjorden, Denmark had resulted in a significant decline of the cover of large brown algae, especially Saccharina latissima (studied as Laminaria saccharina), Halidrys siliquosa, Codium fragile and Fucus vesiculosus. Therefore, Sargassum muticum appears to able to completely replace or significantly reduce the extent of Halidrys siliquosa, and other algae, and an intolerance of high has been recorded. Recoverability has been assessed as high (see additional information below). | ||||
Not relevant | Not relevant | Not relevant | Not relevant | |
No evidence of the extraction or harvesting of Halidrys siliquosa was found. | ||||
Tolerant* | Not relevant | Not sensitive* | Low | |
Svendsen (1972; summary only) reported that Halidrys siliquosa became one of the dominant macroalgae, 3 years after kelp harvesting in Norway. This suggests that removal of other algae species that compete with Halidrys siliquosa for space and light would be beneficial. |
- no data -
National (GB) importance | - | Global red list (IUCN) category | - |
Native | - | ||
Origin | - | Date Arrived | Not relevant |
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Centre for Environmental Data and Recording, 2018. Ulster Museum Marine Surveys of Northern Ireland Coastal Waters. Occurrence dataset https://www.nmni.com/CEDaR/CEDaR-Centre-for-Environmental-Data-and-Recording.aspx accessed via NBNAtlas.org on 2018-09-25.
Environmental Records Information Centre North East, 2018. ERIC NE Combined dataset to 2017. Occurrence dataset: http://www.ericnortheast.org.ukl accessed via NBNAtlas.org on 2018-09-38
Fenwick, 2018. Aphotomarine. Occurrence dataset http://www.aphotomarine.com/index.html Accessed via NBNAtlas.org on 2018-10-01
Fife Nature Records Centre, 2018. St Andrews BioBlitz 2014. Occurrence dataset: https://doi.org/10.15468/erweal accessed via GBIF.org on 2018-09-27.
Fife Nature Records Centre, 2018. St Andrews BioBlitz 2015. Occurrence dataset: https://doi.org/10.15468/xtrbvy accessed via GBIF.org on 2018-09-27.
Fife Nature Records Centre, 2018. St Andrews BioBlitz 2016. Occurrence dataset: https://doi.org/10.15468/146yiz accessed via GBIF.org on 2018-09-27.
Kent Wildlife Trust, 2018. Biological survey of the intertidal chalk reefs between Folkestone Warren and Kingsdown, Kent 2009-2011. Occurrence dataset: https://www.kentwildlifetrust.org.uk/ accessed via NBNAtlas.org on 2018-10-01.
Kent Wildlife Trust, 2018. Kent Wildlife Trust Shoresearch Intertidal Survey 2004 onwards. Occurrence dataset: https://www.kentwildlifetrust.org.uk/ accessed via NBNAtlas.org on 2018-10-01.
Manx Biological Recording Partnership, 2017. Isle of Man wildlife records from 01/01/2000 to 13/02/2017. Occurrence dataset: https://doi.org/10.15468/mopwow accessed via GBIF.org on 2018-10-01.
Manx Biological Recording Partnership, 2018. Isle of Man historical wildlife records 1990 to 1994. Occurrence dataset: https://doi.org/10.15468/aru16v accessed via GBIF.org on 2018-10-01.
Manx Biological Recording Partnership, 2018. Isle of Man historical wildlife records 1990 to 1994. Occurrence dataset:https://doi.org/10.15468/aru16v accessed via GBIF.org on 2018-10-01.
Manx Biological Recording Partnership, 2018. Isle of Man historical wildlife records 1995 to 1999. Occurrence dataset: https://doi.org/10.15468/lo2tge accessed via GBIF.org on 2018-10-01.
Merseyside BioBank., 2018. Merseyside BioBank (unverified). Occurrence dataset: https://doi.org/10.15468/iou2ld accessed via GBIF.org on 2018-10-01.
National Trust, 2017. National Trust Species Records. Occurrence dataset: https://doi.org/10.15468/opc6g1 accessed via GBIF.org on 2018-10-01.
NBN (National Biodiversity Network) Atlas. Available from: https://www.nbnatlas.org.
OBIS (Ocean Biodiversity Information System), 2023. Global map of species distribution using gridded data. Available from: Ocean Biogeographic Information System. www.iobis.org. Accessed: 2023-06-08
Outer Hebrides Biological Recording, 2018. Non-vascular Plants, Outer Hebrides. Occurrence dataset: https://doi.org/10.15468/goidos accessed via GBIF.org on 2018-10-01.
Royal Botanic Garden Edinburgh, 2018. Royal Botanic Garden Edinburgh Herbarium (E). Occurrence dataset: https://doi.org/10.15468/ypoair accessed via GBIF.org on 2018-10-02.
South East Wales Biodiversity Records Centre, 2018. SEWBReC Algae and allied species (South East Wales). Occurrence dataset: https://doi.org/10.15468/55albd accessed via GBIF.org on 2018-10-02.
Yorkshire Wildlife Trust, 2018. Yorkshire Wildlife Trust Shoresearch. Occurrence dataset: https://doi.org/10.15468/1nw3ch accessed via GBIF.org on 2018-10-02.
This review can be cited as:
Last Updated: 29/05/2008