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From Preservation to Conservation;
the restoration of sand drift dynamics in
Wales.
Sam Bosanquet, Julie Creer, Mike Howe,
Emmer Litt, John Ratcliffe, Ceri Seaton & Karen
Wilkinson
Wales and its coastline
Wales! Hard & Soft coast
= Saltmarsh
= Sand dune
= Soft cliff
= Vegetated sea cliff
Influence of climate change on
sand dune development
• Climatic conditions influence the morphology and
dynamics of dune systems. This is illustrated by
observations of past climate changes and dune
development trends.
• A changing climate influences parameters such as:
rainfall; wind speeds; storminess / wave action;
temperature / evaporation rates.
• A balance of these variables have influenced dune
stability / mobility.
Dune mobility and stability drivers
The principal mobility and stability drivers in coastal dune systems (Pye & Blott, 2012).
Welsh sand dunes,
what’s the problem?
What have we lost in Wales?
Whiteford Burrows
bare sand losses
Newborough Warren
bare sand losses
Loss of bare sand from 1940’s to
2013
Dune system Blown sand (ha)
in 1940s-50s
Bare sand (ha)
in 1940s-50s
Blown sand
(ha) in 2009
Bare sand
(ha) in 2009
Overall
loss (ha)
Gronant Dunes & Talacre Warren 240 26 (11%) 265 15 (6%) 11 (42%)
Tywyn Aberffraw 340 87 (26%) 344 13 (4%) 74 (85%)
Newborough Warren 1364 691 (51%) 1409 40 (3%) 651 (94%)
Morfa Harlech 986 82 (8%) 1066 23 (2%) 59 (72%)
Morfa Dyffryn 692 165 (24%) 696 62 (9%) 103 (62%)
Broomhill & Kilpaison Burrows 336 27 (8%) 336 4 (2%) 23 (85%)
Brownslade & Linney Burrows 332 91 (27%) 332 6 (2%) 85 (93%)
Laugharne & Pendine Burrows 629 108 (17%) 724 15 (2%) 93 (86%)
Pembrey Burrows 1677 86 (5%) 1871 34 (2%) 52 (60%)
Whiteford Burrows 148 77 (52%) 164 16 (14%) 61 (79%)
Llangennith Burrows 190 60 (32%) 186 9 (5%) 51 (85%)
Crymlyn Burrows 268 13 (5%) 323 2 (0.6%) 11 (85%)
Baglan Burrows 518 66 (13%) 574 11 (2%) 55 (84%)
Kenfig Burrows 878 154 (18%) 874 4 (0.5%) 150 (97%)
Merthyr Mawr Warren 559 218 (39%) 581 20 (3%) 198 (91%)
TOTAL 9157 1951 (21%) 9745 274 (3%) 1677 (86%)
Directional trend
Observation of a directional trend towards stabilisation…
Images of Kenfig sand dune system, south Wales
1941 1962 1982 1999 2006
Image source: KPAL 2014 and Pye & Blott, (2012)
Meesia uliginosa
Bryum calophyllum
No bare sand. So what?
Liparis loeselii
Biodiversity losses
• Bryophytes
• Bryum calophyllum – now extinct
• Catoscopium nigritum – now extinct
• Meesia uliginosa – now extinct
• Fen orchid Liparis loeselii (S1903)
• Since the late 1980s, the species has been lost from three
(Pendine Burrows, Crymlyn Burrows and Baglan Burrows)
out of 5 Welsh sand dune systems on which it occurred.
• Invertebrates
• Broscus cephalotes – once widespread across dunes is
now restricted to the narrow strandline.
Key research conclusions
Radical action is needed! Grazing,
mowing, scrub clearance and shallow
scrapes have failed to halt the decline
of key dune and dune slack species
(Rhind & Jones, 2009).
‘Coverage of 30-40% pioneer dune and
dune slack habitats, including 10-15% bare
sand, can be regarded as the minimum
required in a dynamic dune system capable
of supporting a wide range of species and
habitats’ (Pye & Blott, 2012).
Climate change is unlikely to reverse dune
stabilisation (Houston & Dargie, 2010)
Areas of rejuvenation at
Newborough Warren & Forest
Newborough Bare sand
created (ha)
Phase 1
Winter 2012-2013 3.96
Phase 2
Winter 2013-2014
Zone 1 West
Zone 1 East
3.85
3.54
Phase 3
Winter 2014-2015 6.63
Total 14.44
Pre-works 40 ha (3% of site) = Bare sand
Post-works 54 ha (4% of site) = Bare sand
Phase 2
Phase 1
Phase 3
Areas of rejuvenation at Kenfig
Site
Bare sand created (ha)
July
2012
May
2013
March
2014
March
2015
Phase 1 2.97 2.97 2.69 2.42
Phase 2 n/a 4.52 4.20 5.32
Phase 3 n/a n/a n/a 2.46
Total 2.97 7.49 6.88 10.20
Pre-works 4 ha (0.5% of site) = Bare sand
Post-works 14 ha (1.5% of site) = Bare sand
Phase 2
Phase 1
Phase 3
Dune slack scrapes
Does it work?
Invertebrate records
Newborough Warren
• In 2013,
• 7 / 16 pioneer dune beetle species
colonising newly created damp
exposed sand.
• In 2015
• 9 / 16 pioneer dune beetle species
colonising bare sand in rejuvenation
areas.
• Several of these species had been scarce
or apparently absent from the site prior to
the rejuvenation work.
• Principal Component Analysis has
grouped the fauna of the excavated slacks
on Newborough Warren close to the
natural pioneer slacks found on Morfa
Dyffryn
Kenfig Burrows
• In 2014,
• Pitfall trapping by Natural Resources
Wales in an excavation on Kenfig
Burrows recorded Bembidion
pallidipennis in large numbers (over
600 specimens), having been last
recorded on this system in 1992.
• Three other slack specialists (Bledius
fergussoni, Dyschirius politus and
Tachytrechus insignis) were also found.
• The Vernal Bee Colletes cunicularius has
also been able to colonise excavations,
nesting in sand banks at Kenfig Burrows
Does it work?
Fen orchid (Liparis loeselii)
2007 – 241 plants on Kenfig Burrows
DUNE SLACK SCRAPING
2014 - 44 plants on Kenfig Burrows
2015 - 412 plants on Kenfig Burrows (10,000
plants in 1970s and early ‘80s)
2017 – 1016 plants in turf-stripped slack
Options for the future
Do nothing! Be bold!
Future plans for Wales
Sands of LIFE LIFE17 NAT/UK/000023
• Restoration benefitting
• 1465 ha of H2130*
• 12 ha of H2120
• 37 ha of H2170 & H2190 (specifically
for P. ralfsii, R. rupestris and L. loeselii)
• 10 frontal dune notches
• 12 ha of re-profiled dunes
• 23 ha of H2130* mowed
• 12 ha of dune slacks scraped &
created
• 44 ha native scrub removed
• 681 ha of duneland cleared of IAS
• 7 ha of conifers removed
• 14ha dunes cleared of conifer stumps
• Appropriate and sustainable grazing
on 1185 ha of dunes
• Rabbit populations supplemented at
3 sites
• Existing rabbit populations managed
at 7 sites
• Unexploded ordnance cleared from
28 ha of dunes
• Monitor outcomes & promote best
practice on other sites
• Raised public understanding of the
dynamic nature of dunes and the
value of sand dune habitats and
species
• We are still waiting to hear if we have
the funding!!!!!
Conclusions
• Stabilisation has reduced the intrinsic geomorphological interest of the
sites and poses a threat to the nature conservation interests.
• The trials currently underway are intended to determine the feasibility of
restoring a greater degree of sand mobility
• It will only be possible to determine the degree of success through
monitoring over a five to ten year period
• The trials offer great opportunities for new research into the interactions
between physical, chemical and ecological processes.
• Next steps…….. Sands of LIFE (LIFE17 NAT/UK/000023)
Thank you (Diolch yn fawr!)