Population distribution and conservation status of notable ...

SURVEY
Despite their scarcity there has been no recent survey to establish status and
population size of S. rupicola and S. porrigentiformis within Torbay. Given the
uncertainty of these population sizes and the potential effects of planned site
management, it is important that a monitoring programme is established to
ensure maintenance of these populations. No seedlings were recorded or
observed by Bradshaw in 1984/5 and there is concern that the populations are
not successfully recruiting. Historic Ordnance Survey maps and photographs of
the two predominantly wooded sites, Babbacombe and Churston, from late
1800’s to the 1930’s, show them to have been open grassland with scrub with
occasional small trees scattered across the slopes.
Sites
The areas surveyed were
1. Babbacombe slopes SSSI – an area between Babbacombe downs and
the coast. (Fig. 3). NGR SX 926 656
2. Redgate Cliffs SSSI – from Redgate beach up the cliff face between
Ansteys cove and Walls Hill. (Fig. 4). NGR SX 934 647
3. Churston Cove CWS – an area stretching from fishcombe point across to
the battery gardens. (Fig.5). NGR SX 917 570
Note: Wall’s Hill was surveyed in 2010, see Appendices photographs pg 20.
The 2008 survey repeated that of Margaret Bradshaw in 1984-5 in order to detect
any changes in population size during the last 23 years. All records have been
lodged with the county recorder for vascular plants, R.E. N. Smith.
All trees had their location recorded with a 10 figure GPS (Global Positioning
System) coordinate with the accuracy of the GPS unit noted. The locations of the
trees were also described and mapped on large scale site maps. (Figures 3-5).
The larger trees were tagged using aluminium tree tags which carry a unique
identifying number and the canopy density was measured.
Using tree ring data from stems found already broken it was possible to estimate
the stem ages of other trees and thus calculate recruitment since 1985.
DISTRIBUTION ACROSS THE SITES
Between them, the three study sites support or have supported 100% of all S.
rupicola ever recorded in Torbay and 80 – 90% of S. porrigentiformis.
Habitats present
All the sites have steep coastal slopes, cliffs and quarried areas. Babbacombe
and Redgate have areas of loose rock. Babbacombe is dominated by high
canopy Ash Fraxinus excelsior and Sycamore Acer pseudoplatanus and there is
little open habitat. Churston also has large areas of similar woodland but also
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