Responses of rich-fen Annex I and related habitats to restoration and management undertaken as part of the Anglesey & Lyn Fens LIFE Project

Published source details Birch K.S., Guest J.E., Shepherd S., Milner P., Jones P.S. & Hanson J. (2015) Responses of rich-fen Annex I and related habitats to restoration and management undertaken as part of the Anglesey & Lyn Fens LIFE Project. LIFE Project: Anglesey & Llyn Fens report, Technical Report No. 7.
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This study is summarised as evidence for the following.

	Action	Category
	Use grazing to maintain or restore disturbance Action Link
	Use prescribed fire to maintain or restore disturbance Action Link
	Cut/mow herbaceous plants to maintain or restore disturbance Action Link

Use grazing to maintain or restore disturbance

A replicated before-and-after study in 2011–2013 in a degraded fen in Wales, UK (Birch et al. 2015) found that grazing typically increased cover of grass-like plants but had no effect on other vegetation cover, diversity or structure. Cover of grasses/sedges/rushes significantly increased in two of three grazed plots (from 78–79% before grazing to 93–105% after 16–21 months of grazing). There was no significant change in two of three plots (but a decrease in the other) in purple moor grass Molinia caerulea cover, dwarf shrub cover, fen-characteristic moss cover, fen-characteristic herb cover, plant species richness, plant diversity or vegetation height. Three 10 x 10 m plots were established in an abandoned fen. From spring or summer 2012, each plot was grazed by cattle or ponies. Before grazing began (August 2011) and after 16–21 months (autumn 2013) measurements were taken in five 4 m² quadrats/plot. Cover of every plant species was estimated, and vegetation height was measured, in the centre of each quadrat.

(Summarised by: Nigel Taylor)
Use prescribed fire to maintain or restore disturbance

A replicated before-and-after study in 2010–2012 in a degraded fen in Wales, UK (Birch et al. 2015) reported that burning (along with other interventions) reduced grass/sedge/rush and shrub cover, but typically had no effect on fen-characteristic plant cover and overall diversity, and had mixed effects on vegetation height. In both managed plots, there were decreases in total grass/sedge/rush cover (before burning: 97–98%; two years after: 70–74%) and shrub cover (before: 7–81%; after: 10–13%). Cover of purple moor grass Molinia caerulea decreased significantly in one plot with a similar trend in the other (before: 4–64%; after: 0–3%). There was no significant change in cover of fen-characteristic mosses (<1% before and after), fen-characteristic herbs (before: <2%; after: <1%), or plant species richness/diversity (in three of four comparisons). Vegetation height decreased in one plot but did not change in the other. Two 20 x 20 m plots were established in an abandoned fen. In September 2011, both plots were burned. After burning, one plot was mown and both plots were lightly grazed by cattle. The study does not distinguish between the effects of these interventions and burning. Cover of every plant species was estimated before burning (August 2008) and two years after (autumn 2013), in five 4 m² quadrats/plot.

(Summarised by: Nigel Taylor)
Cut/mow herbaceous plants to maintain or restore disturbance

A replicated before-and-after study in 2010–2013 in two degraded fens in Wales, UK (Birch et al. 2015) found that mowing (sometimes along with other interventions) reduced shrub and grass/sedge/rush cover, typically had no effect on cover of fen-characteristic species and plant richness/diversity, and had mixed effects on vegetation height. In five of six managed plots, there were declines in shrub cover (before intervention: 27–87%; after 2–3 years: 9–19%) and total grass/sedge/rush cover (before: 91–98%; after: 63–80%). Cover of purple moor grass Molinia caerulea decreased in three plots (before: 64–81%; after: 3–34%). In four or five plots, there was no change in cover of fen-characteristic mosses (<1% before and after), fen-characteristic herbs (before: <2%; after: <1%), plant species richness (before: 9–17; after: 8–14 species/4 m²) or plant diversity (data reported as diversity indices). Management had mixed effects on vegetation height (increase: 1 plot; decrease: 2 plots; no change: 3 plots). Six 20 x 20 m plots were established across two abandoned fens. In autumn 2010 or spring 2011, each plot was mown once. Cuttings were removed. Four plots were also grazed. Two of these were also burned. The study does not distinguish between the effects of these interventions and mowing. Cover of every plant species was estimated before mowing (autumn 2010) and 2–3 years after (autumn 2012 or 2013), in five 4 m² quadrats/plot.

(Summarised by: Nigel Taylor)