Explanatory table for the information given on sensitivity to human activities

Factor Category Definition
Biotope sensitivity   The intolerance of a habitat or community of species to damage, or death, from an external factor. Defined by the following categories:
  High Keystone/dominant species in the biotope or habitat are likely to be killed/destroyed by the factor under consideration.
  Intermediate Some of the keystone/dominant species in a community may be killed/destroyed by the factor under consideration, the habitat may be partially destroyed or the viability of a species population or diversity/functionality in a community will be reduced.
  Low Keystone/dominant species in a community or the habitat being considered are unlikely to be killed/destroyed by the factor under consideration and the habitat is unlikely to be damaged.  However, the viability of a species population or diversity / functionality in a community will be reduced.
  Not sensitive The factor does not have a detectable effect on structure and functioning of a biotope or the survival or viability of keystone/important species
  Not sensitive* The extent or species richness of a biotope may be increased or enhanced by the factor.
  Not relevant Sensitivity may be assessed as not relevant where communities and species are protected or physically removed from the factor (for instance circalittoral communities are unlikely to be effected by increased emergence regime).
Benchmarks Substratum removal All of the substratum occupied by the species or biotope under consideration is removed. Once the activity or event has stopped (or between regular events) substratum within the habitat preferences of the original species or community remains or is deposited. A single event is assumed for assessment.
  Substratum change All of the population of a species or an area of a biotope is smothered by sediment to a depth of 5 cm above the substratum for one month. Impermeable materials, such as concrete, oil or tar, are likely to have a greater effect

[In the case developments, the substratum is replaced by new material, e.g. from construction]

  Siltation A change in suspended sediment concentration of 100mg/1 outside the normal range experienced by the organism or community of interest for 1 year.
  Desiccation A normally subtidal, demersal or pelagic species including intertidal migratory or under surface species is continuously exposed to air and sunshine for 1 hour.
  Changes in emergence regime A 1 hour change in the time covered or not covered by the sea for a period of 1 year.
  Changes in water flow rate A change of two [MNCR] categories in water flow rate for one year for 1 year. For example from moderately strong (1-3 knots) to very weak (negligible).
  Changes in temperature A change of 5 C outside normal temperature range for 3 consecutive days. This definition includes short term thermal discharges.

A change in temperature of 2 C outside normal temperature range for a year. This definition includes long term thermal discharges.

For intertidal species, the normal range of temperatures includes the normal air temperature regime for that species.

  Changes in turbidity Exposed to 50 mg/l suspended particulate matter or light absorption of 30% for five weeks.
  Changes in wave exposure A change of two ranks on the [MNCR] wave exposure scale e.g. from Exposed to Extremely exposed for a period of 1 year.
  Noise Underwater noise levels 130 dB re 1 ÁPa (for broad spectrum noise 45 – 7070 Hz) at 100 m from source intermittently over a 24 hour period for 1 month during important feeding or breeding periods. This approximates to the regular passing of a 30 m-trawler at 100 m or a working cutter-suction transfer dredge at 100 m.

Atmospheric noise levels 98 dB re 1 ÁPa (for broad spectrum noise 45 – 7070 Hz) at 300 m below the source on and off over a twenty-four hour period for 1 month during important feeding or breeding periods. This approximates to the regular passing of a Boeing 737 passenger jet 300 m overhead.

  Visual presence The continuous presence for one month of moving objects not naturally found in the marine environment (e.g. boats, machinery, and humans) within the visual envelope of the area in which the species under consideration occurs.
  Synthetic compound contamination Environmental Assessment Level/Environmental quality Standard (for seawater unless otherwise stated): Exposed to the following contaminant concentration:
    Tributyl tin: 0.002 m g/l (Maximum Allowable Concentration) Long term: 0.004 m g/l average in seawater for a 1 year period

Short term: 1 m g/l seawater for 2 days (48hrs)

    DDT (all isomers): 0.025/l annual average Long term: 0.05 m g/l average for 1 year

Short term: 0.25 m g/l for 48hrs

    Lindane (g -HCH): 0.02m g/l annual average. Long term: 0.04 m g/l average in seawater for a 1 year period

Short term: 0.2 m g/l for 48hrs

  Heavy metal contamination Environmental Assessment Level/Environmental quality Standard (for seawater unless otherwise stated): Exposed to the following contaminant concentration:
    Copper: 5 m g/l annual average Long term: 10 m g/l annual average for 1 year period.

Short term: 50 m g/l for 48hrs

    Mercury: 0.3 m g/l annual average
0.13 mg/kg for sediments
Long term: 0.6m g/l annual average for 1 year, or 0.26 mg/kg in sediments for 1 year

Short term: 3 m g/l for 48hrs

  Hydrocarbon contamination Environmental Assessment Level/Environmental quality Standard (for seawater unless otherwise stated): Exposed to the following contaminant concentration:
    Benzo(a)pyrene: 88.8 m g/kg sediment Exposed to 176 m g/kg in sediment for 1 year.
  Radionuclide contamination Exposure to concentration of radionuclide equivalent to 100 mBg/l. of caesium-137 (137Cs) for 1 year.
  Changes in nutrient levels A change of total nitrogen of 3 mg/l and/or phosphorus of 0.3 mg/l as an annual average. Alternatively, a 50% increase of nutrients as an annual average.
  Changes in salinity A change of one category from the MNCR salinity scale, e.g. from reduced to low for 1 year.

A change of two categories from the MNCR salinity scale, e.g. from full to reduced for 1 week.

  Changes in de-oxygenation Exposure to dissolved oxygen concentration of 2 mg/l for 1 week.
  Abrasion Force equivalent to a standard lobster pot or creel landing on the organism.
  Displacement Removal of the organism from the substratum and displacement from its original position onto a suitable substratum. A single event is assumed for assessment.
  Introduction of microbial pathogens and parasites Sensitivity can only be assessed relative to a known, named disease. Likely to cause partial loss of a population and will be assessed of intermediate sensitivity.
  Introduction of non-native species Sensitivity assessed against the likely effect of the introduction of non-native species in Britain or Ireland.
  Removal of target species Extraction removes 50% of the species from the area under consideration.

The habitat remains intact or recovers rapidly.

  Removal of non-target species A species that is a required host or prey for the species under consideration (and assuming that no alternative host exists) or a keystone species in a biotope is removed.
Human activities   * Activities which have been assigned a sensitivity score in this report
  Aquaculture  
  Aquaculture: algae  
  Aquaculture: fin-fish *  
  Aquaculture: shellfish  
  Climate change/global warming *  
  Coastal defence  
  Coastal defence: barrage  
  Coastal defence: beach nourishment *  
  Coastal defence: dredging *  
  Coastal defence: groynes  
  Coastal defence: sea walls/breakwaters *  
  Collecting (harvesting)  
  Collecting: algae (not kelp/wrack harvesting)  
  Collecting: bait digging *  
  Collecting: birds eggs  
  Collecting: curio  
  Collecting: higher plants  
  Collecting: kelp/wrack harvesting *  
  Collecting: peelers (boulder turning) *  
  Collecting: shellfish (winkles, mussels) *  
  Collecting: trade in wildlife  
  Development  
  Development (culverting lagoons)  
  Development: artificial reefs  
  Development: communication cables  
  Development: docks, ports & marinas *  
  Development: land claim *  
  Development: urban/industrial  
  Extraction (of resources)  
  Extraction: maerl *  
  Extraction: navigational/maintenance dredging *  
  Extraction: oil/gas  
  Extraction: rock/minerals (coastal quarrying)  
  Extraction: sand/gravel (aggregate dredging) *  
  Fishing  
  Fishing: angling *  
  Fishing: fixed netting (gill/tangle)  
  Fishing: mobile netting (seine)  
  Fishing: potting/creeling *  
  Fishing: suction/hydraulic dredging  
  Fishing: benthic trawling *  
  Fishing: pelagic trawling  
  Recreation  
  Recreation: diving/dive site  
  Recreation: marina  
  Recreation: popular beach/resort *  
  Recreation: water sports  
  Uses: archaeology  
  Uses: boats/shipping  
  Uses: boats/shipping (anchoring/mooring) *  
  Uses: boats/shipping (anti-fouling) *  
  Uses: boats/shipping (beaching/launching)  
  Uses: boats/shipping (oil spills) *  
  Uses: coastal forestry/farming *  
  Uses: education/interpretation  
  Uses: energy generation (wind/tide/wave)  
  Uses: freshwater extraction/storage on land  
  Uses: military  
  Uses: research  
  Waste  
  Waste: air (pollution)  
  Waste: cooling water (power stations) *  
  Waste: industrial effluent discharge *  
  Waste: land/riverine drainage (pollution)  
  Waste: litter and debris  
  Waste: nuclear effluent discharge  
  Waste: quarry waste dumping  
  Waste: sewage discharge *  
  Waste: spoil dumping *  

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