© Lisa Jarvis (CC BY 2.0). Kindly recommended by UKCEH.
The following is a short summary of the habitat type and how to create/enhance it to a "good" condition. For an informed position, please refer to official up-to-date EUNIS documentation or the UK Government's Condition Assessment Sheet.
Littoral coarse sediments include shores of mobile pebbles, cobbles and gravel, sometimes with varying amounts of coarse sand. The sediment is highly mobile and subject to high degrees of drying between tides. As a result, few species are able to survive in this environment. Beaches of mobile cobbles and pebbles tend to be devoid of macroinfauna, while gravelly shores may support limited numbers of crustaceans, such as Pectenogammarus planicrurus.
Littoral coarse sediments are found along relatively exposed open shores, where wave action prevents finer sediments from settling. Coarse sediments may also be present on the upper parts of shores where there are more stable, sandy biotopes on the lower and mid shore.
The sediment particle size structure may vary seasonally, with relatively finer sediments able to settle during calmer conditions in summer. Where the sediment grain size is very large (at the interface between sediment and boulder shores), cobbles may be mobile during exposed winter conditions, but stable enough during summer months to support limited juvenile rocky shore epifauna (e.g. juvenile barnacles).
This aligns with the description provided by EUNIS A2.1.
How to Create / Enhance to a "Good" condition
⚠️ Important Note
The design and management of coastal habitats will have specific competency requirements which should be demonstrated where these habitats are targeted in the SSM.
There are a set of criteria that are used to judge the condition of this habitat. These are listed below.
| Indicator | Good (3 points) | Moderate (2 points) | Poor (1 point) |
A | Coastal processes | Coastal processes are functioning naturally. No evidence of human physical modifications which are clearly impacting the habitat. | Artificial structures present e.g. groynes, that are impeding the natural movement of sediments or water, affecting up to 25% of the habitat. | Artificial structures present e.g. groynes, that are impeding the natural movement of sediments or water, affecting more than 25% of the habitat. |
B | Presence and abundance of invasive non-native species | Not more than one invasive non-native species is ‘Occasional’ on the SACFOR scale or is occupying more than 1% of the habitat. No high-risk species indicative of suboptimal condition present, see Footnote 1 for details. | No invasive non-native species are present above ‘Frequent’ on the SACFOR scale or they occupy between 1-10% of the habitat. No high-risk species indicative of suboptimal condition present, see Footnote 1 for details. | One or more invasive non-native species are present at an ‘Abundant’ level on the SACFOR scale; they occupy more than 10% of the habitat; or a high-risk species indicative of suboptimal condition is present – GB Non-native Species Secretariat should be notified, see Footnote 1 for details. |
C | Water Quality | No visual evidence of pollution. There are no nuisance algal growths that are likely to be attributable to nutrient enrichment. Consider seasonality of survey timing2. | Visual evidence of low to moderate levels of pollution. Elevated algal growth with increases in cover that may indicate nutrient enrichment. Consider seasonality of survey timing2. | Visual evidence of high algal growth that is indicative of nutrient enrichment. Signs of eutrophication that would impede bird feeding. Consider seasonality of survey timing2. |
D | Non-natural structures and direct human impacts | No evidence of impacts from direct human activities, or they occupy <1% of the habitat area (for example, pontoons, moorings, boats, crab tiles, bait digging or anchoring scars). | Evidence of impacts from direct human activities occupies 1-10% of the habitat area (for example, pontoons, moorings, boats, crab tiles, bait digging or anchoring scars). | Evidence of impacts from direct human activities occupies >10% of the habitat area (for example, pontoons, moorings, boats, crab tiles, bait digging or anchoring scars). |
E | Litter (when examining a beach strandline, mean high water line or intertidal rocky shore) | Following the Marine Conservation Society (MCS) beach litter survey method, the number of items of litter does not exceed 0.0036 m−1 min−1 person−1, equivalent to up to 20 items per person per 100 m per hour. See Footnote 3 for details. | Following the MCS beach litter survey method, the number of items of litter does not exceed 0.0078 m−1 min−1 person−1, equivalent to between 21 and 47 items of litter per person per 100 m per hour. See Footnote 3 for details. | Following the MCS beach litter survey method, the number of items of litter exceeds 0.0078 m−1 min−1 person−1, equivalent to more than 47 items of litter per person per 100 m per hour. See Footnote 3 for details. |
Condition Assessment Result |
TOTAL SCORE 12-15 (75-100%) = GOOD CONDITION |
TOTAL SCORE 8-11 (50-75%) = MODERATE CONDITION |
TOTAL SCORE 5-7 (0-50%) = POOR CONDITION |
Footnotes |
Footnote 1 - Abundances estimated using SACFOR scales details available here: JNCC (No date) SACFOR abundance scale used for both littoral and sublittoral taxa from 1990 onwards [online]. Available from: sacfor.pdf (jncc.gov.uk) Use the non-native species list available here: Microsoft Word - UK_Marine_NIS_priority_list_2020 (nonnativespecies.org)
DEFRA (2022) UK Marine Non-Indigenous Species Priority List (updated 2020) [online]. Available on: Marine Pathways Group » NNSS (nonnativespecies.org)
Intertidal mixed sediment A2.4
Footnote 2 - Peak bloom time is July – September.
NELMS, S.E. ET AL. (2017) Marine anthropogenic litter on British beaches: A 10-year nationwide assessment using citizen science data. Science of The Total Environment [online], 579. Available from:
The indicator thresholds for litter are based on the methods in Van Loon et al (2020), which is guidance developed within the Common Implementation Strategy for the Marine Strategy Framework Directive (MSFD) by the MSFD Technical Group on Marine Litter.
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