Page 13 - Conservation Impact Report 2016

Conservation Impact

■■ Consistent grazing and scrub control help ensure
that chalk grassland sites remain floristically diverse.
One typical chalk grassland reserve has 34% cover
of rockrose (Helianthemum nummularium), 50%
cover of scabious species (Scabiosa columbaria
& Knautia arvensis) and 46% quaking grass (Briza
media); all of which are now classified as Near
Threatened, due to their decline in the ‘wider
countryside’.

■■ Silver-spotted skippers (Hesperia comma) are
expanding their range northwards in part due to
climate change. Management of chalk grassland
ensures the abundant short sward required by
this species is present, so promoting potential
colonisation by the occasional vagrants recorded
on sites. One site already supports a strong
population of this butterfly with a maximum count
of 19 individuals in 2014.

■■ Seven chalk grasslands support populations of Chiltern gentian
pure Chiltern gentian. Driven by the plant’s life
cycle requirements numbers vary significantly
between years. In any given year there can be over
10,000 individual plants. Following scrub removal
numbers have significantly increased at one of the
seven sites. Data is not available for years following
2013 as the population was too numerous to count
accurately (see figure 5).

Figure 5. Chiltern gentian numbers at one chalk grassland nature reserve

26 Extent & Distribution of UK Lowland Grassland Habitats, Joint Nature Conservation Committee, jncc.defra.gov.uk/page-5848 (accessed 12 August
2016)
27 Meadows, Grass and Pasture: Introduction, Low Impact, www.lowimpact.org/lowimpact-topic/meadows-grass-pasture (accessed 12 August 2016)
28 P.A Stroh et al., A Vascular Plant Red List for England, Botanical Society of Britian and Ireland, Bristol, 2014.
29 K.J. Walker and C.E Pinches, Reduced Grazing and the Decline of Pulsatilla Vulgaris Mill. (Ranunculaceae) in England, UK, Biological Conservation,
144 2011, p. 3098–3105.

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