Preprint volume - SIBM

Pre-print Volume – Introductory lecture
Topic 1: BIODIVERSITY AND CONSERVATION SCIENCE: CONTRIBUTING TO MANAGEMENT
under the MSFD by 2012. The report has highlighted the challenge of defining the
desired “status” of UK seas, which has particular relevance to setting the
baselines/reference conditions that will inform discussions on defining GES.
Measuring progress towards the vision in UK seas - A large number of marine
scientists were involved in CP2: the HBDSEG report alone has contributions from over
150 scientists (including 99 primary authors) representing 40 institutions and
encompassing information from the academic and research communities as well as
experts in government agencies and Non-Governmental Organisations. CP2, therefore,
provides the largest and most comprehensive assessment ever taken of the health of
marine ecosystems in UK waters. The CP 2 report is made up of four separate feeder
reports relating to the different aspects of the vision: an Ocean Processes report
containing information on the physical and oceanographic conditions in UK seas; a
Productive Seas report with an analysis of economic productivity; a Clean and Safe
Seas report with an assessment of contaminants and other inputs; and a Healthy and
Biologically Diverse Seas report with an assessment of the state of the marine
environment in terms of its habitats and species. The focus here is the latter report
which looks at the status of habitats (Intertidal Rock; Intertidal Sediments; Subtidal
Rock; Shallow Subtidal Sediments; Shelf Subtidal Sediments, and Deep-Sea Habitats);
microbes; plankton; marine and estuarine fish; seals; turtles; cetaceans and seabirds and
waterbirds. Information from surveys, monitoring programmes and long-term time
series is used where available to assess the various components whilst information on
pressures is provided by the “Clean and Safe Seas” and “Productive Seas” reports.
Data are analysed to provide information on changes in habitats and species since the
last report in 2005 as well as changes from “natural conditions”. Where possible and
appropriate, results are reported for eight UK regions.
Assessing trends in UK habitats and species - For some components such as
microbes and turtles there is too little information available to make any assessment
and for some components such as cetaceans and estuarine fish conclusions are based on
fairly limited data so necessarily tentative. For other components the picture is mixed
with concerns over trends in sedimentary habitats; improvements in many fish
communities; continuing changes in plankton communities linked with increasing sea
temperatures; declines in numbers of harbor seals and seabirds but increases in the
number of waterbirds. The assessment of habitats depends largely on looking at trends
in the distribution and intensity of pressures with this forming the basis of the
assessment.
Assessing the state of UK habitats and species – what do we mean by the vision? -
Whether the focus is on survey and monitoring data or on pressures information, an
assessment based on trends can be many of the marine components. However, the
picture becomes more complicated when trying to make an assessment of state i.e. how
near or far is the component under investigation from the status articulated by the
“vision”. As there is no agreement on what the status should be overall or for
individual species and habitats, different criteria are used to establish a reference point
or baseline that represents this status. For example, when assessing species it is
generally assumed that high population abundances are a good thing and that declines
in abundance are not (e.g. seals, seabirds and waterbirds, cetaceans) and that high
biodiversity is also desirable (e.g. fish). For others (e.g. plankton) changes in
abundance or diversity are not considered a problem as long as the change is largely
“natural change” i.e. not driven by anthropogenic pressures. For habitats, it is assumed
41 st S.I.B.M. CONGRESS Rapallo (GE), 7-11 June 2010
18