Fish Stock Survey of Lough Macnean Upper, August 2022
Lough Macnean Upper is the larger of the two Macnean lakes, situated on the border of counties Fermanagh, Leitrim and Cavan at an altitude of 47m a.s.l. (Plate 1.1, Figure 1.1). It is a mesotrophic lake with a surface area of 644ha, mean depth of 5.2m and maximum depth of 22.7m. The lake falls into typology class 8 (as designated by the EPA for the Water Framework Directive), i.e., deep (>4m), greater than 50ha and moderately alkaline (20-100mg/l CaCO3).
Lough Macnean Upper is fed by several rivers (Lurgan, Esky and Black Rivers) and flows into Lough Macnean Lower via the Belcoo River. Both Lough Macnean Upper and Lough Macnean Lower were formed by a process of glaciation. Glaciers excavated deep basins in the carboniferous rocks, creating steep valley sides and rocky cliffs (NIEA, 2009a). The shores of the lake have good examples of wet woodland and extensive fen and reed bed communities (NIEA, 2009b). The islands on the lake are important breeding sites for lapwing (Vanellus vanellus), snipe (Gallinago gallinago) and curlew (Numenius arquata) (NIEA, 2009b). The white-clawed crayfish (Austropotamobius pallipes), a species listed on Annex II of the EU Habitats Directive, has been recorded in the lake (NIEA, 2009b).
Lough Macnean Upper is a mixed coarse fishery and is particularly noted for its pike angling. The shoreline is broken up by areas of woodland and sheltered bays fringed with reed swamps and fen (NIEA, 2009a). Agricultural usage along the shoreline of the lake is not very developed when compared to the lower lake. Surrounding fields tend to be rush-infested with overgrown hedges (NIEA, 2009a).
A survey carried out in 1969 revealed perch (Perca fluviatilis), pike (Esox lucius), roach (Rutilus rutilus), roach x bream hybrids (Rutilus rutilus x Abramis brama) and brown trout (Salmo trutta) were present in Lough Macnean Upper (IFT, unpublished data). The lake was again surveyed in 2006, 2010, 2013 and 2016 (Kelly et al., 2007, 2011, 2014 and 2017). During the 2016 survey, perch were found to be the dominant species present in the lake. Roach, pike, bream (Abramis brama), roach x bream hybrids, eels (Anguilla anguilla) and brown trout were also recorded.
This report summarises the results of the 2022 fish stock survey carried out on the lake using Inland Fisheries Ireland’s fish in lakes monitoring protocol. The protocol is WFD compliant and provides insight into fish stock status in the lake.
Topics: Lake Surveys 2022 , Lough Macnean Upper |