Figure 12 – Sites where <strong>Pulsatilla</strong> <strong>vulgaris</strong> is now extinct (all photos taken 2003-2006; year of last record indicated): (a) Fleam Dyke, Cambridgeshire (1973); (b) Shacklewell Hollow, Leicestershire (1992); (c) Hildersham Furze Hills, eastern (Sand) hill, Cambridgeshire (1990); (d) Honnington Camp, Lincolnshire (1992); (e) Pitstone Hill, Buckinghamshire (1996); (f) Southorpe Roughs, Northamptonshire (1990). 28
Losses to ploughing and quarrying continued into the twentieth century and by the 1960s only 29 populations remained (Wells & Barling, 1971). Losses since then have mainly been caused by increased above-ground competition, particularly with Bromopsis erectus, as a result of under-grazing (Walker et al., in press). Ironically this was first observed in grazing exclosures that were erected to protect populations from over-grazing (e.g. Carter, 1967; Wells, 1971). Of the 20 sites where <strong>Pulsatilla</strong> <strong>vulgaris</strong> has either declined or gone extinct since the 1960s, 16 have been ungrazed for over 40 years or have only received intermittent grazing, mowing or burning (Table 9). These include small areas of grassland on earthworks or steep banks that are now completely isolated within arable landscapes and are now partly or completely scrubbed-over (e.g. Fleam Dyke, Fig. 12a; Honnington Camp, Fig. 12d), small exclosures erected to exclude livestock, deer and rabbits on over-grazed sites (e.g. Aston Upthorpe Down, Fig. 13a) and privately managed nature reserves where resources for management have been limited (e.g. Ancaster Valley, Fig. 13). This decline of grazing frequency and intensity on many sites has been due to the reduced profitability of livestock farming in arable areas since the 1950s which has made it difficult to sustain appropriate grazing management on unproductive sites (Nisbet & Shere, 2006). On mixed farms the conversion of grassland to arable has made farmers less committed to grazing small areas, whereas their inaccessibility has deterred potential graziers because of increased transport and infrastructure costs. Even on livestock farms these problems have prevented the grazing of small fragments of semi-natural grasslands perceived to be unproductive and/or difficult to manage. In addition, there has been a decline in rabbit grazing since the spread of myxomatosis in 1953 which is known to have caused dramatic successional changes, especially on sites with no history of livestock grazing (Sumpton & Flowerdew, 1985). Table 9 - Management of <strong>Pulsatilla</strong> <strong>vulgaris</strong> populations in relation to trends in abundance, 1968-2006. 1-5 represent a decline in the intensity of grazing management. Extant Management since 1968 1. Winter + some spring/summer/autumn Increas e Stable Decline Extinc t Total grazing 3 2 - - 5 2. Winter grazing (since 1980) 2 1 - - 3 3. Irregular grazing, mowing, burning - 4 2 2 8 4. Over-grazed then under-grazed - - 2 3 5 5. Ungrazed for over 40 years - - - 7 7 6. Improved/destroyed - - - 4 4 7. Unknown - 1 - - 1 Over the last 40 years many grassland sites have also been agriculturally improved and reseeded to increase productivity. Other threats have included the digging-up of plants for horticulture including over 1000 from Knocking Hoe in 1948 (Hope-Simpson, 1948) and more recently at Barton Hills (M. Gurney, pers. comm.). In addition, the last known plants were dug-up at two former sites (Broughton Far Wood, Fleam Dyke; Marren, 1999) although other factors were more important in causing declines. Other direct threats, including forestry, building developments, etc. have only caused a few losses, including the dumping of rubble on the last Leicestershire colony. More recently there has also been concern, but no direct evidence, that atmospheric nitrogen deposition may be adversely affecting some populations through eutrophication of infertile grassland (Crawley, 2005; Rich et al., 1993). 29
- Page 1 and 2: Pulsatilla vulgaris (L.) Mill. Pasq
- Page 3 and 4: 1 Morphology, identification, taxon
- Page 5 and 6: Pulsatilla is now generally accepte
- Page 7 and 8: 2 Distribution and current status 2
- Page 9 and 10: UK VU Declined from ca.130 to 18 lo
- Page 11 and 12: English populations, the overall nu
- Page 13 and 14: surviving in each year, and (c) the
- Page 15 and 16: maturation before the male (andro-
- Page 17 and 18: 3.1.6 Seed dispersal Achenes of Pul
- Page 19 and 20: the sward and thereby determining t
- Page 21 and 22: Table 6 - Chemical and mechanical a
- Page 23 and 24: Figure 9 continued. Habitats of Pul
- Page 25 and 26: Cavenham Heath) support extensive a
- Page 27: Kalliovirta et al., 2006). There ar
- Page 31 and 32: . (a) Sites in good condition, graz
- Page 33 and 34: Quarry, Ancaster 1996 Most scratche
- Page 35 and 36: 7.4 Monitoring and the Common Monit
- Page 37 and 38: Kalliovirta, M., Ryttäri, T. & Hei
- Page 39 and 40: Warden, K. 2001. An investigation i
- Page 41 and 42: 11 Annex 1 - site descriptions Desc
- Page 43 and 44: Historically Pulsatilla has been re
- Page 45 and 46: In the 1960s a small population occ
- Page 47 and 48: introduced by the National Trust le
- Page 49 and 50: 13 Annex 2 - changes in population
- Page 51 and 52: Annex 3 continued. All sites Limest
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