Conservation of Maerl (Calcareous red seaweed) in Europe
Submitting Institution
Queen's University BelfastUnit of Assessment
Earth Systems and Environmental SciencesSummary Impact Type
EnvironmentalResearch Subject Area(s)
Environmental Sciences: Ecological Applications, Environmental Science and Management
Biological Sciences: Ecology
Summary of the impact
The application of legislation and policy protecting European maerl
habitats under the EC Habitats
Directive has been strengthened by research at QUB showing that maerl,
coral-like seaweed, is
slow-growing, intolerant of disturbance and burial, and supports high
biodiversity. A new marine
Natura 2000 Special Area of Conservation (SAC) in Northern Ireland
was designated for maerl in
2010. Maerl beds in the Fal and Helford SAC, the largest in England, were
protected in 2009 from
channel dredging until a Scientific Panel including a QUB academic has
considered the results of a
maerl-relocation trial in 2013.
Underpinning research
Context: Maerl beds, formed by unattached coralline red algae, are
marine habitats with high
conservation importance due to their high biodiversity. They are
threatened globally by
commercial extraction as a calcareous resource for agricultural and
industrial applications. The
EC Habitats Directive, which forms the cornerstone of Europe's nature
conservation policy, gives
legislative protection to maerl. The maerl-forming species Phymatolithon
calcareum and
Lithothamnion corallioides are the only seaweeds included in Annex
V, as "species of Community
interest whose taking in the wild and exploitation may be subject to
management measures".
Maerl habitats are protected in the Natura 2000 network of Special
Areas of Conservation (SACs)
within the Annex I category "Sand banks which are slightly covered by sea
water all the time".
QUB research: From 1983 onwards, when Christine Maggs (initially
postdoctoral fellow; lecturer
from 1995) joined phycologist Matthew Dring, QUB researched the ecology
and conservation of
maerl. In 1998, new analyses of their data on the biodiversity of maerl
beds in Britain and Ireland
were reported in a comprehensive synthesis for the UK Marine SACs LIFE
project.1This showed
that the biodiversity of seaweeds on maerl beds equalled that of shallow
Mediterranean algal
communities, the highest previously recorded in Europe.1Their
analysis highlighted two of the
most serious knowledge gaps concerning management of maerl: growth rates
and longevity1. In
2001- 2004, Maggs and PhD student Charmaine Blake used a novel vital
staining technique to
demonstrate slow growth rates (0.5-1.5 mm per annum) of P. calcareum
and L. corallioides in the
field and laboratory.2The results confirmed previous
speculation that commercial harvesting
cannot be sustainable and that maerl habitats are very vulnerable to
physical disturbance.2
Maggs, algal physiologist John Berges (who moved to the University of
Wisconsin Milwaukee in
2006) and students Blake and Sian Wilson found with PAM fluorometry that
maerl species are
highly sensitive to disturbance by burial, particularly by anoxic
sediments.3 Radiocarbon-dating of
dead maerl beds in Northern Ireland by Blake, in collaboration with Paula
Reimer (who leads
QUB's 14Chrono Centre), showed that catastrophic maerl bed
extirpation had occurred in
Strangford Lough during a period of rapid sedimentation associated with
climatic change 4200
years ago.4 In Belfast Lough a maerl bed had died
contemporaneously with extensive 19th
century channel dredging that re-mobilised toxic sediment. Combined with
our experimental
evidence that sedimentation kills maerl, we concluded that channel
dredging probably caused the
death of the Belfast Lough maerl bed4. These results accorded
with field observations in Scotland
by Jason Hall-Spencer on damage to maerl by sediment from scallop dredging
and aquaculture.
Maggs, marine ecologist Mark Johnson (who moved to NUI Galway in 2009)
and their research
group found that in Northern Ireland there was a suite of rare seaweeds
confined to maerl
habitats5. Experimental stabilization of maerl showed that
biodiversity of maerl beds is particularly
dependent on the nature and extent of adjacent habitats, requiring
conservation measures to take
the spatial context of beds into account6.
References to the research
1) Birkett, D.A., Maggs, C.A. & Dring, M.J. (1998). An overview of
dynamics and sensitivity
characteristics for conservation management for marine SACs. Vol 5. Maerl.
Scottish
Association for Marine Science (UK Marine SACs Project). 116 pp.
[http://www.ukmarinesac.org.uk/pdfs/maerl.pdf]
2) *Blake, C. & Maggs, C.A. (2003). Comparative growth rates and
internal banding periodicity
of maerl species (Corallinales, Rhodophyta) from northern Europe. Phycologia,
42: 606-612.
3) *Wilson, S., Blake, C., Berges, J.A. & Maggs, C.A. (2004).
Environmental tolerances of free-living
coralline algae (maerl): implications for European marine conservation. Biological
Conservation, 120: 283-293.
4) Blake, C., Maggs, C.A. & Reimer, P. (2007). Use of radiocarbon
dating to interpret past
environments of maerl beds. Ciencias Marinas 33: 385-397.
5) Wilson, S., Johnson, M.P., Kelly, J., Clarkin, P.E. & Maggs, C.A.
(2007). Assessment of
extent and abundance of maerl beds and their associated biodiversity along
the East Antrim
coast. NIEA Research & Development Series (ISSN 1751-7796
Online).
6) *Hinojosa, G., Johnson, M.P. & Maggs, C.A. (2009). Like a rolling
stone: the mobility of
maerl (Corallinaceae) and the neutrality of the associated assemblages. Ecology,
90: 517-528.
*References that best indicate the quality of the underpinning research
Details of the impact
Our impact on legislation, designations, policy and practice: QUB
research on maerl beds
and their biodiversity (Sections 2, 3) has had impact since 2008, in the
context of member states'
obligations to protect maerl under the 1992 Habitats Directive. QUB
research has benefitted the
environment through traceable inclusion in current government policy
papers, legislation and
planning decisions designed to reduce or mitigate anthropogenic impacts on
maerl in Northern
Ireland, Great Britain and Europe.
Northern Ireland: QUB research contributed to setting specific
targets and actions of the Northern
Ireland Environment Agency (NIEA)'s Habitat Action Plan (HAP) for maerl
beds, published in
2003 and still in effect.S1 The HAP was designed to
deliver Northern Ireland's contribution to the
UK Biodiversity Action Plan (UKBAP) for maerl. It cites our published
research1and describes
(Sections 1.1, 3.2) ongoing QUB projects, some commissioned by the NIEA,
that were later
published2,3and contributed to achieving the HAP targets. Maerl
beds and Phymatolithon
calcareum are respectively a Northern Ireland Priority Habitat and
Species.
In 2010 our research on the extent and biodiversity of a maerl bed off
the Antrim coast near Red
Bay5 (commissioned through Quercus, our biodiversity
partnership with the NIEA) was used to
designate a new marine SAC for this Annex 1 habitat: "The Red Bay
sandbanks are dominated by
both living maerl and sub-fossil maerl and have been thoroughly mapped and
characterised as
part of this SAC selection assessment".S2This new SAC
with its ancient maerl beds was
welcomed by local media as "Northern Ireland's answer to the great
tropical reefs" and NIEA
spokesman Joe Breen cited our research: "It's the only known site in
Northern Ireland for the
orange northern starfish ... Some of the surface sub-fossil [maerl has
been] carbon-dated to 650
years".S3
Great Britain: The Habitats Directive was implemented in Great
Britain as The Conservation
(Natural Habitats, &c.) Regulations 1994 (now The Conservation of
Habitats and Species
Regulations 2010). The Joint Nature Conservation Committee (JNCC)
designated Phymatolithon
calcareum as a UKBAP Priority Species in 2007 (updated 2010)S4
using criteria including the slow
growth rate.2 From July 2012, under the UK Post-2010
Biodiversity Framework, UKBAP work is
carried out at country level and has moved to BARS (Biodiversity Action
Reporting System).S5
The current Vision Statement for the National Action Plan for maerl beds
notes "Our knowledge of
the maerl resource is continuing to grow although it remains
incomplete.... recent completion of
postgraduate projects at University Marine Biological Station Millport and
Queen's University
Belfast (and subsequent publications in the scientific literature) has
significantly improved
understanding of maerl ecology and sensitivity to impacts..."S5
The Fal and Helford SAC includes the largest maerl bed in England; the
SAC Management
SchemeS6 cites our research.1 In 2009
Falmouth Harbour Commissioners applied to the Marine
Management Organisation (MMO), as the `competent authority' under the
Regulations, to licence
work involving dredging a channel through the maerl beds. The
Environmental Statement by
Royal Haskoning cites our research.1
An independent maerl recovery report by Jason Hall-Spencer cited our
paper on extinction of
maerl beds4 and considered that there would be potential loss
of maerl habitat.S6 Natural England
advised the MMO that the proposal was likely to have a significant effect
on the designated
features of this protected European site. Therefore, under the
Regulations, an appropriate
assessment was required to assess the impact of the proposed development
on the conservation
objectives of the site. The MMO's assessment was that "it cannot be
concluded that there would
be no adverse effect on the integrity of the Fal and Helford SAC" and the
application to dredge
was rejected.S8 The MMO required further research into
mitigation measures, and in 2011
recruited Maggs (QUB) to an Independent Science Advisory Panel (ISAP) of
"five independent
scientists who have significant and recognised expertise in maerl ecology,
experimental design
and the wider impacts on benthic ecology from dredging operations".S9
In 2012 the MMO
approved a licence for a maerl-relocation trial to take place, overseen by
the ISAP, to determine
whether this novel approach can safeguard Falmouth's maerl.
Europe: In 2008, Maggs and Jason Hall-Spencer (University of
Plymouth) were commissioned to
prepare an assessment of maerl for OSPAR on behalf of the Department of
the Environment,
Heritage (now Community) & Local Government, Ireland S10.
The 1998 OSPAR Convention, the
instrument guiding international cooperation on the protection of the
North-East Atlantic marine
environment, lists maerl beds (Agreement 2008-6) as threatened and/or
declining. Our
assessment, with recommendations for actions and measures that could be
taken to improve the
conservation status of maerl, delivers one of Ireland's commitments under
OSPAR.
Sources to corroborate the impact
S1) Northern Ireland Habitat Action Plan: http://www.doeni.gov.uk/niea/biodiversity/habitats-2/northern_ireland_habitat_action_plans.htm
[gives link to] Maerl Beds Final Draft — April 2003 [currently in force —
July 2013]
http://www.doeni.gov.uk/niea/maerl_beds_web_version_april_03-3.pdf
S2) Red Bay marine SAC
http://jncc.defra.gov.uk/protectedsites/sacselection/sac.asp?EUCode=UK0030365
S3) Belfast Telegraph 3 March 2010 Protected: the ancient coral-like
seaweed off Northern
Ireland's coast
http://www.belfasttelegraph.co.uk/news/local-national/protected-the-ancient-corallike-seaweed-off-northern-irelands-coast-14705369.html#ixzz1kMZVqpKN
S4) Phymatolithon calcareum UK Biodiversity Action Plan Priority
Species
http://jncc.defra.gov.uk/_speciespages/2508.pdf
S5) Biodiversity Action Reporting System archived maerl Biodiversity
Action Plan status
http://webarchive.nationalarchives.gov.uk/20110303145213/http://www.ukbap-reporting.org.uk/plans/national_plan.asp?HAP=%7BF8A12650%2D4C02%2D4FA8%2DB5
49%2D160D29156658%7D&SAP=
S6) Fal and Helford SAC management scheme
http://publications.naturalengland.org.uk/file/3118614
S7) Hall-Spencer, J. (2009) Port of Falmouth Development Initiative:
maerl 'recovery' report.
http://www.marinemanagement.org.uk/licensing/public_register/cases/falmouth.htm
S8) http://marinemanagement.org.uk/licensing/public_register/cases/documents/falmouth/evide
nce_summary.pdf
S9) http://www.marinemanagement.org.uk/
licensing/public_register/cases/documents/falmouth/friends_factsheet.pdf
S10) Hall-Spencer, J.M., Kelly, J. & Maggs, C.A. (2010) Background
document for maërl beds.
OSPAR Commission, 491/2010, 36pp. ISBN 978-1-907390-32-6.
www.ospar.org/documents%5Cdbase%5Cpublications%5CP00491_maerl.pdf
Individual users/beneficiaries who can be contacted to corroborate
claims
Principal Scientific Officer, Marine Conservation and Reporting, Northern
Ireland Environment
Agency.