Guide for non-scientists

Like many science based projects, the Mapping European Seabed Habitats project, or MESH for short, can at first appear a little impenetrable, however, it only takes a little bit of background information to understand what it is setting out to achieve and why it is so important.  This article has been written specifically to cover this information in order to make MESH more accessible to the non-scientist and hopefully to convey why the team are so enthused by the project!
It is said that more is known about the surface of Mars than the bottom of our seas and to some degree this is true.  Looking off our own North West European coast you will find we have a very poor knowledge of seabed habitats. There is some information, but only for restricted areas, gathered using different techniques and stored in a multitude of institutions across several countries.  The aim of the MESH project is to improve this situation so that we end up with information about a far wider area, gathered using the best possible techniques, accessible through one central location.  Before we look at how we intend to do this, we need to take a step back and explain just what a seabed habitat is.

What is a seabed habitat?

Seabed habitats define the environmental conditions at particular points at the bottom of the sea.  On land you might consider habitat types as being things like forest, marsh, or grassland, for example.  Areas of the same habitat type are shown on habitat maps as areas of the same colour.
BGS Seabed Sediment Map © BGS
North West Irish Sea BGS seabed sediment map (DigSBS250)
BGS 2004)
There is an extensive hierarchy of habitat types, ranging from basic descriptions (high level classifications) such as 'sandy beach' or 'Littoral rock and other hard substrata' through to very detailed descriptions (low level classifications) such as 'Lanice conchilega in littoral sand' and 'Chthamalus montagui and Chthamalus stellatus on exposed upper eulittoral rock' (!). The habitat type at a given location will depend on the depth of the sea above it, the rocks underlying it, the currents flowing over it and a multitude of other factors. Sometimes these factors combine to produce unique conditions, such as those under which cold water corals grow on the seabed in the North Sea.
Sandy Seabed Habitat © Cefas  Gravel Seabed Habitat © Cefas
Sandy seabed habitat
CEFAS 2004)
Gravel seabed habitat
It is important to note that a specific habitat material does not necessarily define alone or exactly what creatures live in or on it; but the seabed environment is a very good indication of what can and may live in a given area.  If you can play windows movie files (.WMV)  to view two videos of seabed habitats.
Until recently people had different ways of classifying marine habitats but a European standard from the European Environment Agency, the 'European Nature Information System' (EUNIS) has given us the ability to gather information in a consistent manner.

Why is it so important to have seabed habitat maps?

There are many demands placed on our marine environment; in addition to the current demands placed on them by fishing and the extraction of oil, gas and aggregates (gravel extraction), there are increasing pressures from things such as offshore wind-farms and leisure activities.  You might have heard in the news recently how marine species are in decline as a consequence of activities such as bottom trawling and dredging.  Seabed habitat maps provide vital information to help us obtain a balance between these demands and conservation.
Blyth offshore wind-farm © AMEC
Blyth offshore wind-farm

How do you produce a seabed habitat map?

To produce a map of seabed habitats you need to survey the seabed at regular intervals either by sending a diver down to look at the seabed, towing a video camera behind a boat or grabbing a sample and bringing it back up to the boat for analysis.  The technique you use will depend on the quality of data you need, the location, depth, area to be covered etc.  The results are plotted on a grid and the areas in between can be filled in with estimates of what is there based on the results.
Grab Sample  Diver
Sampling method: grab
(© CEFAS 2008)
Diver Conducting Survey

Who is involved in the MESH project?

Because marine habitats, by their nature, do not respect international boundaries, it is key to the success of the project to involve as many countries as possible.  We therefore built the project team from twelve partners across five countries: Belgium, France, Ireland, the Netherlands and the UK.  This trans-national cooperation has been helped, and the importance of the project recognised, by partial funding from the EU via its INTERREG funding program.  Working with this number of partners from so many different backgrounds can be difficult at times but it is not only interesting, but also greatly beneficial to creating results that are useful to as wide an audience as possible.
Geographic Area © MESH
MESH project area

What is MESH doing?

The intention of the MESH project is not to go out and map the entire North West Europe seabeds (this would be a huge job in terms of both time and cost).  Instead, our first task was to bring together and collate all the existing maps held in Europe (some dating back to 1870) and to harmonise them into the standard European classification scheme.  This information is now available through an interactive web-based mapping system.
Alongside this have worked to set standards and protocols for the use of surveying and sampling methods and technologies in marine habitat mapping.  This will help improve the quality and consistency of future survey work.
During the process of setting these standards we needed to do some field study work in order to test them for both quality and practicality.  Doing this testing work also contributed data to help fill in gaps in the information we have managed to gather together.
Once we had gathered together and assessed all existing data as well as setting and testing standards the results revealed large gaps in the information that we have.  Ideally we would have liked to survey all these areas, but as before, cost is a large factor.  Instead, we developed methods to predict habitats based on many factors including; depth, temperature and underlying rock type, i.e. use the existing information we had access to predict the seabed habitats.  As well as filling in gaps in the information coverage this also helped us understand the processes determining the existence of a particular habitat in a particular location.
Doing all this work will be of limited benefit unless we work closely with the scientific community who create these maps and with those who use them.  A key part of the project was therefore to hold workshops for interested parties and to demonstrate the value of habitat maps for sustainable marine resource management.

Is there life after MESH?

All the information and products from the website continue to be made freely available through the project website.  There has also been plenty of valuable, ongoing work, for example, since the completion of the MESH project, the EUSeaMap project has developed the predictive modelling capabilities using a finer resolution and extends over a much wider area and MESH Atlantic extended the coverage of habitat maps down the Atlantic coast of Europe to Gibraltar.
From 2014 until 2016 the second phase of the EUSeaMap project (AKA EMODnet Seabed Habitats) will continue the work of EUSeaMap, MESH and MESH Atlantic to product a broad-scale predicitive habitat map for all EU waters).