Biodiversity & Conservation

Beggiatoa spp. on anoxic sublittoral mud



Image Keith Hiscock - A mat of the filamentous bacterium Beggiatoa spp. Image width ca 10 cm.
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Distribution map

SS.SMu.IFiMu.Beg recorded (dark blue bullet) and expected (light blue bullet) distribution in Britain and Ireland (see below)

  • EC_Habitats

Text page icon Habitat description

Map icon Distribution of biotope in Britain and Ireland Recorded on the coast of the Shetland Isles and the west coast of Scotland. Also recorded in South Donegal Bay in Ireland. Often a feature of the seabed below fish cages in sheltered locations.
National importance Not available

Text page icon Description of biotope

For a full description of this biotope including characterizing species, distribution, survey information and references visit JNCC

Sublittoral soft anoxic mud, often in areas with poor water exchange with the open sea, can have a conspicuous bacterial mat covering of Beggiatoa species. The anoxia may be a result of natural conditions of poor water exchange in some sea lochs (and many Scandinavian fjords) or artificially under fish farm cages from nutrient enrichment. The fauna is normally impoverished at such sites, with few elements of the infaunal communities present in other muddy biotopes. Scavenging species such as Asterias rubens and Carcinus maenas are typically present where the habitat is not too anoxic but in extreme conditions of anoxia little survives other than the Beggiatoa. The polychaete Ophiodromus flexuosus occurs in high densities at the interface between oxygenated and deoxygenated sediments (in Norwegian fjords). (Information taken from the Marine Biotope Classification for Britain and Ireland, Version 97.06: Connor et al., 1997a, b).

Additional information icon Additional information

None entered

This review can be cited as follows:

Hill, J.M. 2002. Beggiatoa spp. on anoxic sublittoral mud. Marine Life Information Network: Biology and Sensitivity Key Information Sub-programme [on-line]. Plymouth: Marine Biological Association of the United Kingdom. [cited 30/11/2015]. Available from: <>