Extent & Distribution of UK Freshwater Habitats

 

The tables below give information on the extent and distribution of freshwater habitats around the UK.  This shows that:

  • many UK lakes fall into the eutrophic category, having a relatively high nutrient status, and including around 80% of lakes in England, 40% in Wales, 15% in Scotland - Northern Ireland alone accounts for around half of all UK eutrophic lake area, including Lough Neagh, which is by far the largest area of freshwater in the British Isles covering 386 km2, and the Upper and Lower Lough Erne which covers 144 km2
  • mesotrophic lakes are relatively infrequent in the UK and largely confined to the margins of upland areas in the north and west - several of the largest and most important lakes, including Lough Neagh and Lower Lough Erne, were once mesotrophic but are now classified as eutrophic
  • comprehensive information on the extent of nutrient poor, oligotrophic and dystrophic lakes is not available - these are, nevertheless, numerous, occurring most often in the uplands of the north and west, which makes them difficult to access and quantify
  • aquifer-fed naturally fluctuating water bodies is a very rare habitat - there are a few known turloughs in country Fermanagh (Northern Ireland) and at Pant-y-llyn (South Wales), which combine with a small number of fluctuating meres in the Norfolk Brecklands
  • ponds represent a numerous, generally widespread, and familiar type of freshwater habitat - it has been estimated that around 20% of the c.400,000 ponds outside curtilage in the UK might meet with the UK BAP Ponds priority habitat definition

 

UK BAP habitats

 

The table below shows the estimated extent of the freshwater priority habitat types recognised by the UK Biodiversity Action Plan. The values are mainly based on information extracted from the Biodiversity Action Reporting System (BARS).  Note that detailed information on the extent of river habitats is mostly unavailable.

 

UK BAP priority habitats

England

Scotland

Wales

Northern

Ireland

UK

Eutrophic standing waters

3,916 lakes

1,012 lakes

150 lakes

650 lakes

5,734 lakes

Mesotrophic lakes

644 lakes

1,749 lakes

50 lakes

111 lakes

2,554 lakes

Aquifer-fed naturally fluctuating water bodies

16.5 ha

1 ha

6.5 ha

24 ha

Ponds

unknown

unknown

unknown

unknown

80,000 ponds

 

EU Habitats Directive Annex I types

 

The table below shows the estimated extent of UK freshwater habitats listed under Annex I of the EU Habitats Directive. The data is derived from the 2013 UK Report on Implementation of the Habitats Directive.

 

EU Habitats Directive Annex I types (click here to see further information on each habitat)

 

England

(ha)

Scotland

(ha)

Wales

(ha)

Northern

Ireland

(ha)

UK

(ha)

H3150 Natural eutrophic lakes with Magnopotamion or Hydrocharition-type vegetation

17,880

unknown

689

14,800

unknown

H3130 Oligotrophic to mesotrophic standing waters with vegetation of the Littorelletea uniflorae and/or of the Isoëto-Nanojuncetea

10,050

unknown

1,900

2,359

unknown

H3110 Oligotrophic waters containing very few minerals of sandy plains (Littorelletalia uniflorae)

980

unknown

unknown

H3140 Hard oligo-mesotrophic waters with benthic vegetation of Chara spp.

670

unknown

97

166

unknown

H3160 Natural dystrophic lakes and ponds

180

unknown

35

80

unknown

H3170 Mediterranean temporary ponds

10

10

H3180 Turloughs

0.66

3.96

4.62

H3260 Water courses of plain to montane levels with the Ranunculion fluitantis and Callitricho-Batrachion vegetation

unknown

unknown

2,000

unknown

unknown