Red threads (Cirratulus cirratus)
Cirratulus spp.
Photographer: Teresa Darbyshire Copyright: Amgueddfa Cymru - Museum Wales
Distribution data supplied by the Ocean Biodiversity Information System (OBIS). To interrogate UK data visit the NBN Atlas.Map Help
| Researched by | Ken Neal & Susie Ballerstedt | Refereed by | This information is not refereed |
| Authority | (O. F. Müller, 1776) | ||
| Other common names | Northern cirratule | Synonyms | - |
Summary
Description
Cirratulus cirratus has a long, slender, orange, pinkish or brownish-red body, with 75 to 130 segments, and can reach 12 cm in length. The head is a blunt cone with a row of 4 to 8 large black eyes either side that may meet on top of the head. There are two groups of up to 8 feeding tentacles on the first segment. Pairs of long slender gills arise at intervals from the whole length of the body and these appear as a mass of reddish threads when the worm is buried.
Recorded distribution in Britain and Ireland
Found in suitable habitats all round the coast of Britain and Ireland.Global distribution
Most north west European coasts and also in the south Atlantic.Habitat
Occurs on the lower shore in mud or muddy sand beneath or between rocks.Depth range
Mainly intertidal but may be circalittoral.Identifying features
- Long, slender body with 75 to 130 segments.
- Up to 12 cm in length.
- Blunt head with 4 to 8 large, black eyes.
- Body is orange, pinkish or brownish red.
- Two pairs of up to 8 feeding tentacles near the head.
- Paired, thread-like gills present along most of the body.
Additional information
Cirratulus cirratus is usually found in aggregations of up to 200 individuals. During the breeding season their colour changes, the females become bright yellow and the males white.
Listed by
- none -
Biology review
Taxonomy
| Phylum | Annelida | Segmented worms e.g. ragworms, tubeworms, fanworms and spoon worms |
| Class | Polychaeta | Bristleworms, e.g. ragworms, scaleworms, paddleworms, fanworms, tubeworms and spoon worms |
| Order | Terebellida | |
| Family | Cirratulidae | |
| Genus | Cirratulus | |
| Authority | (O. F. Müller, 1776) | |
| Recent Synonyms | ||
Biology
| Typical abundance | Moderate density | ||
| Male size range | 5 - 130mm | ||
| Male size at maturity | 20mm | ||
| Female size range | Medium(11-20 cm) | ||
| Female size at maturity | |||
| Growth form | Cylindrical | ||
| Growth rate | See additional information. | ||
| Body flexibility | High (greater than 45 degrees) | ||
| Mobility | |||
| Characteristic feeding method | Non-feeding, Surface deposit feeder | ||
| Diet/food source | |||
| Typically feeds on | Diatoms and algal detritus. | ||
| Sociability | |||
| Environmental position | Infaunal | ||
| Dependency | No information found. | ||
| Supports | No information | ||
| Is the species harmful? | No | ||
Biology information
Little information on the general biology or life history characteristics of this species was found. Cirratulus cirratus is regarded as a generally tolerant species and can be found in moderate densities in areas of high environmental disturbance (e.g. 120 per m² 500 m away from an oil platform) (Levell et al., 1989). Once larvae and juveniles settle, they remain in their burrow and adults do not move. It can grow up to 2 cm between reproductive episodes, which occur every 1-2 years (Olive, 1970).
Habitat preferences
| Physiographic preferences | Open coast, Offshore seabed, Strait / sound |
| Biological zone preferences | Lower circalittoral, Lower eulittoral, Lower infralittoral, Mid eulittoral, Sublittoral fringe, Upper circalittoral, Upper eulittoral |
| Substratum / habitat preferences | Mud, Muddy gravel, Under boulders |
| Tidal strength preferences | Weak < 1 knot (<0.5 m/sec.) |
| Wave exposure preferences | Extremely sheltered, Sheltered, Very sheltered |
| Salinity preferences | Full (30-40 psu), Reduced (18-30 psu), Variable (18-40 psu) |
| Depth range | Mainly intertidal but may be circalittoral. |
| Other preferences | No text entered |
| Migration Pattern | Non-migratory / resident |
Habitat Information
In Northumberland it is the dominant crevice organism on rocky shores between low and high water neaps (Olive, 1970). Cirratulus cirratus has been described as an opportunistic deposit feeder that is characteristic of areas of organic enrichment (Penry & Jumars, 1990). Cirratulus cirratus is mostly intertidal but is sometimes found subtidally (up to 50 m depth off the Devon coast) (Garwood, 1982; Olive, 1970).Life history
Adult characteristics
| Reproductive type | Gonochoristic (dioecious) | |
| Reproductive frequency | Biannual episodic | |
| Fecundity (number of eggs) | No information | |
| Generation time | 1-2 years | |
| Age at maturity | 1-2 years | |
| Season | See additional text | |
| Life span | 5-10 years |
Larval characteristics
| Larval/propagule type | - |
| Larval/juvenile development | Lecithotrophic |
| Duration of larval stage | < 1 day |
| Larval dispersal potential | No information |
| Larval settlement period | Insufficient information |
Life history information
Reproduction in Cirratulus cirratus is asynchronous i.e. it is not entrained to any of the seasons and members of the population are at different stages of reproductive development at any one time (Garwood, 1982; Gibbs, 1971). Oocytes are 150 µm in diameter and once fertilized are deposited in a jelly mass on the surface of rocks (Petersen, 1999). The eggs hatch as a ciliated post-trochophore after 6 days. The larvae are entirely benthic for the duration of their development, living off yolk for around 24 days after hatching and then commence adult style deposit feeding (Olive, 1970). Females can spawn 2-3 times in their lifetime and it takes 1-2 years after each spawning to mature a new clutch of oocytes (Olive, 1970). There are separate sexes, the males are white, females are lemon-yellow due to the colour of coelomic oocytes (Gibbs, 1971). Sex ratios vary and have been recorded as 1:1 (Olive, 1970) 1:1.7 and 1:2.8 (Gibbs, 1971).Asexual reproduction by epitoky (clones growing from the posterior end of the worm) may occur in Cirratulus cirratus. However, the taxonomic status of Cirratulus is in constant review and epitokes may be formed by another species that has been erroneously identified as Cirratulus cirratus (Petersen, 1999).
Sensitivity review
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.
Physical pressures
| Intolerance | Recoverability | Sensitivity | Evidence/Confidence | |
| High | Low | High | Very low | |
| Cirratulus cirratus needs stones to live under in a muddy environment and if these were to be removed, mortality is likely to be very high due to desiccation and predation and an intolerance of high has been recorded. For recoverability see additional information. | ||||
| High | Low | High | Very low | |
| Cirratulus cirratus lives in mud under stones with its feeding tentacles spread out on the mud surface. A sudden influx of sediment would probably interfere with feeding and gas exchange and cause high mortality. Therefore, an intolerance of high has been recorded. For recoverability see additional information. | ||||
| Tolerant* | Not relevant | Not sensitive* | Very low | |
| Cirratulus cirratus is often found in estuaries (Clay, 1967g), which are areas of high suspended sediment and it is likely that it is tolerant to an increase in suspended sediment. Cirratulus cirratus feeds on precipitating particles and is likely to benefit from an increase in suspended organic matter. Therefore tolerant* has been recorded. | ||||
| Low | Very high | Very Low | ||
| A decrease in suspended sediment is unlikely to make Cirratulus cirratus more vulnerable to predation. Cirratulus cirratus relies on particulate organic matter precipitating onto the substratum for food, so that a decrease in suspended particulates may reduce its food supply. However, the reduced turbidity may increase benthic primary productivity, which would be of benefit to Cirratulus cirratus. Overall, its food supply may be reduced and an intolerance of low has been recorded. | ||||
| Not relevant | Not relevant | Not relevant | Not relevant | |
| Cirratulus cirratus lives in mud under stones and is therefore unlikely to be subject to desiccation. Not relevant has been recorded. | ||||
| Intermediate | High | Low | Very low | |
| Cirratulus cirratus is found from the subtidal up to the high water of neap tide level and an increase in emergence time is likely to exclude worms from the upper limit of their range. There would probably be some mortality near high water neap tide level and a shift of the population down to the new high water neaps level. Therefore, an intolerance of intermediate has been recorded. | ||||
| Tolerant* | Not relevant | Not sensitive* | ||
| A decrease in emergence is likely to have the opposite effect of an increase and extend the range of the population up the shore to the new high water neaps level. Therefore, tolerant* has been recorded. | ||||
| Intermediate | High | Low | Very low | |
| Cirratulus cirratus feeds by laying its tentacles out on the surface of the mud and passing food particles to the mouth by ciliary movements. An increase in water flow rate may affect the ability of Cirratulus cirratus to collect food particles. Also, an increase in water flow rate may change sediment characteristics and remove the preferred sediment type of Cirratulus cirratus. In increase in water flow, e.g. from weak to strong (see benchmark) is likely to significantly affect the substratum, removing fine muddy deposits, and reducing the area of suitable habitat for Cirratulus cirratus. Therefore, an intolerance of intermediate has been recorded. | ||||
| Not relevant | Not relevant | Not relevant | ||
| Cirratulus cirratus is found in estuaries and on muddy shores, where the water flow rate is slow so a decrease in water flow rate is unlikely to affect this species and this factor has been assessed as not relevant. | ||||
| Tolerant | Not relevant | Not sensitive | Moderate | |
| Cirratulus cirratus probably has wide temperature tolerances (7-25°C (Gibbs, 1971). Cirratulus cirratus is probably tolerant of temperature changes at the benchmark level. | ||||
| Low | High | Low | High | |
| Cirratulus cirratus probably has wide temperature tolerances (7-25°C (Gibbs, 1971). During the extremely cold winter in the United Kingdom in 1962-63, the distribution of Cirratulus cirratus did not change (George, 1968). Cirratulus cirratus survived temperatures as low as -2°C for long periods but was killed after a few hours in -4°C due to ice crystals forming in its tissues (George, 1968). At the benchmark level, Cirratulus cirratus will probably not be adversely affected by a decrease in temperature and an in tolerance of low has been recorded. | ||||
| Tolerant | Not relevant | Not sensitive | Very low | |
| Reduced illumination due to turbidity may reduce the productivity of the microalgae that Cirratulus cirratus feeds upon. However, it also feeds on particulate organic matter and, therefore, is not likely to be adversely affected. | ||||
| Tolerant | Not relevant | Not sensitive | Not relevant | |
| A decrease in turbidity is likely to increase benthic microalgal productivity, which could potentially benefit Cirratulus cirratus. However, the relative contribution of benthic microalgae and organic matter to its diet is unknown. Therefore, tolerant has been recorded. | ||||
| Intermediate | High | Low | Low | |
| Increasing wave exposure increases the incidence of turnover of rocks on the shore and will also increase the size of rocks disturbed (Osman, 1977). If the rocks on the shore are turned over, anything underneath is likely to be washed out of the sediment by subsequent waves and suffer increased predation. Cirratulus cirratus is not a very motile species and if it were revealed by loss of a protecting rock, mortality is likely to be high and an intolerance of intermediate has been recorded to account for this. | ||||
| Not relevant | Not relevant | Not relevant | ||
| Cirratulus cirratus is found from sheltered to extremely sheltered shores and therefore a decrease in wave exposure is not relevant. | ||||
| Tolerant | Not relevant | Not sensitive | High | |
| At most, Cirratulus cirratus will have only a limited ability to detect sound or vibration and therefore is unlikely to be sensitive to noise. | ||||
| Tolerant | Not relevant | Not sensitive | High | |
| Cirratulus cirratus does have eyes but it lives under rocks with only the deposit feeding tentacles exposed and so is probably tolerant to visual presence at the benchmark level. | ||||
| Intermediate | High | Low | Very low | |
| At the benchmark level, abrasion is likely to cause some mortality by moving stones and unearthing the worms. Disturbing rocks may also affect the survivorship of embryos in eggs attached to the rock surface. Therefore an intolerance of intermediate has been recorded. | ||||
| No information | No information | No information | Not relevant | |
| Cirratulus cirratus establishes under rocks in mud as a larva and there was no information on whether adults reburrow if disturbed. There is insufficient information to assess the intolerance of Cirratulus cirratus to displacement. | ||||
Chemical pressures
| Intolerance | Recoverability | Sensitivity | Evidence/Confidence | |
| High | Low | High | High | |
| After a spill of fuel oil in Southampton Water, dispersants were used to clean certain areas and high mortalities of Cirratulus cirratus were observed (George, 1971). Three dispersants were tested for their effects on Cirratulus cirratus survivorship, BP 1002, Essolvene (which was used in Southampton Water) and Corexit 7664. BP 1002 and Essolvene become toxic at 100 ppm. BP 1002 caused 50% mortality at 129 ppm and 100% mortality at 144 ppm. Essolvene was slightly less toxic, causing 50% mortality at 162 ppm and 100% mortality at 200 ppm. Corexit was far less toxic than either BP 1002 or Essolvene. It took a concentration of 100,000 ppm of Corexit 7664 to cause 50% to Cirratulus cirratus. Longer exposure to sublethal concentrations of BP 1002 or Essolvene completely prevented the maturation of oocytes (George, 1971). The evidence presented above suggests an intolerance of high to synthetic chemicals. For recoverability, see additional information below. | ||||
| No information | No information | No information | Not relevant | |
| Insufficient information. | ||||
| Low | High | Low | High | |
| A spill of fuel oil in Southampton water lead to widespread oiling of intertidal mud but this had very little effect on Cirratulus cirratus abundance. The thickness of the oil was not sufficient to prevent oxygen reaching the sediment and at high tide, the oil refloated so that Cirratulus cirratus could feed as normal. Embryo development was also unaffected by oil (George, 1971) and an intolerance of low has been recorded. | ||||
| No information | No information | No information | Not relevant | |
| Insufficient information. | ||||
| Tolerant* | Not relevant | Not sensitive* | Moderate | |
| Cirratulus cirratus is characteristic of areas of organic enrichment (Penry & Jumars, 1990) and therefore is probably tolerant* of an increase in nutrient levels. | ||||
| No information | No information | No information | Not relevant | |
| No information on hypersaline conditions was found. | ||||
| Low | High | Low | ||
| Cirratulus cirratus can tolerate salinities down to 17 psu (Gibbs, 1971) and so is likely to survive the benchmark chronic change as it is normally found intertidally at full salinity. An acute change will probably stress a population of Cirratulus cirratus but not cause high mortality and an intolerance of low has been recorded. | ||||
| Low | High | Low | Very low | |
| Cirratulus cirratus is characteristic of areas of organic enrichment (Penry & Jumars, 1990), although no further information was found. Therefore, an intolerance of low has been recorded, albeit with very low confidence. | ||||
Biological pressures
| Intolerance | Recoverability | Sensitivity | Evidence/Confidence | |
| No information | No information | No information | No information | |
| Insufficient information | ||||
| No information | No information | No information | No information | |
| Insufficient information | ||||
| Not relevant | Not relevant | Not relevant | Not relevant | |
| Cirratulus cirratus is not targeted for extraction. | ||||
| Not relevant | Not relevant | Not relevant | Not relevant | |
| No co-occurring species to Cirratulus cirratus are known to be extracted. | ||||
Additional information
RecoverabilityThe fecundity of Cirratulus cirratus is unknown but the larvae are entirely benthic throughout their development (Olive, 1970) and, if an area is completely defaunated, recolonization by Cirratulus cirratus may be slow (George, 1968). Recovery by populations that suffer partial mortality could take up to 2 years. However, populations that are completely wiped out may not recover at all due to the limited dispersal capability of the larvae of Cirratulus cirratus (George, 1968).
Importance review
Policy/legislation
- no data -
Status
| National (GB) importance | - | Global red list (IUCN) category | - |
Non-native
| Native | - | ||
| Origin | - | Date Arrived | - |
Importance information
-none-Bibliography
Clay, E., 1967g. Literature survey of the common fauna of estuaries, 7. Cirratulus cirratusO.F. Müller. I.C.I. Research Laboratory, Brixham. PVM45/B/380.
Fauchald, K., 1977. The polychaete worms. Definitions and keys to the orders, families and genera. USA: Natural History Museum of Los Angeles County.
Fish, J.D. & Fish, S., 1996. A student's guide to the seashore. Cambridge: Cambridge University Press.
Garwood, P.R., 1982. Polychaeta - Sedentaria incl. Archiannelida. Report of the Dove Marine Laboratory Third Series, 23, 273p.
George, J.D., 1968. The effect of the 1962-63 winter on the distribution of the cirratulid polychaetes, Cirratulus cirratus (Müller) and Cirriformia tentaculata (Montagu) in the British Isles. Journal of Animal Ecology, 37, 321-31.
George, J.D., 1971. The effects of pollution by oil and oil dispersants on the common intertidal polychaetes, Cirriformia tentaculata and Cirratulus cirratus. Journal of Applied Ecology, 8, 411-420.
Gibbs, P.E., 1971. Reproductive cycles in four polychaete species belonging to the family Cirratulidae. Journal of the Marine Biological Association of the United Kingdom, 51, 745-769.
Hayward, P., Nelson-Smith, T. & Shields, C. 1996. Collins pocket guide. Sea shore of Britain and northern Europe. London: HarperCollins.
Hayward, P.J. & Ryland, J.S. (ed.) 1995b. Handbook of the marine fauna of North-West Europe. Oxford: Oxford University Press.
Howson, C.M. & Picton, B.E., 1997. The species directory of the marine fauna and flora of the British Isles and surrounding seas. Belfast: Ulster Museum. [Ulster Museum publication, no. 276.]
JNCC (Joint Nature Conservation Committee), 1999. Marine Environment Resource Mapping And Information Database (MERMAID): Marine Nature Conservation Review Survey Database. [on-line] http://www.jncc.gov.uk/mermaid
Levell, D., Rostron, D. & Dixon, I.M.T., 1989. Sediment macrobenthic communities from oil ports to offshore oilfields. In Ecological Impacts of the Oil Industry, Ed. B. Dicks. Chicester: John Wiley & Sons Ltd.
Olive, P.J.W., 1970. Reproduction of a Northumberland population of the polychaete Cirratulus cirratus. Marine Biology, 5, 259-273.
Osman, R.W., 1977. The establishment and development of a marine epifaunal community. Ecological Monographs, 47, 37-63.
Penry, D.L. & Jumars, P.A., 1990. Gut architecture, digestive constraints and feeding ecology of deposit-feeding and carnivorous polychaetes. Oecologia, 82, 1-11.
Petersen, M.E., 1999. Reproduction and development in Cirratulidae (Annelida: Polychaeta). Marine Biology, 8, 243-259.
Datasets
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.
Fenwick, 2018. Aphotomarine. Occurrence dataset http://www.aphotomarine.com/index.html 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.
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: 2023-03-30
South East Wales Biodiversity Records Centre, 2018. SEWBReC Worms (South East Wales). Occurrence dataset: https://doi.org/10.15468/5vh0w8 accessed via GBIF.org on 2018-10-02.
Citation
This review can be cited as:
Last Updated: 02/05/2006
