Many explorers say humans know more about the surface of the moon than the deep sea. It's almost a cliché to hear but clichés often ring true. The deep sea hosts habitats unseen by our eyes that are essential to the species that use them as areas to feed, shelter, and reproduce. In 2006, the UNGA passed a resolution on sustainable fisheries that called for the protection of these vulnerable marine ecosystems.
Vulnerable marine ecosystems (VMEs) are deep-sea ecosystems that can be adversely impacted by bottom contact fishing gear. VMEs include cold-water coral reefs, coral gardens and deep-sea sponge aggregations. It is quite difficult to positively identify VMEs in deep-water without using specialist underwater camera equipment. However, "VME indicators" are a start for investigation. A VME indicator is a species from a broad group of benthos that is found in trawl bycatch, for example sponges, gorgonians, or stony corals. Their presence indicates that there may be an actual VME habitat on the seabed – for example gorgonians may be a component of coral garden VMEs.
The ICES/NAFO Working Group on Deep-water Ecology (WGDEC) evaluates data on the presence of VMEs in the deep sea in the ICES and NEAFC areas. Group members contribute records of VME indicators and habitats to a VME database each year, which is then used to underpin their work. Over the past few years, significant work has been undertaken by the group and the ICES Data Centre to develop a data portal that publicises all these data on the distribution and abundance of VMEs (and species considered to be indicators of VMEs) across the North Atlantic.
Neil Golding, Chair of WGDEC, is excited about the new portal, "People can now map and explore the data from the VME database and the key thing about the portal is that it differentiates between the VME indicators (often recovered as by-catch) and the VME habitats (observed in situ on the seabed)."
Some VME indicators can be misleading. Golding explains, "Gorgonians can be found dotted across the seafloor but when you find gorgonians as bycatch it doesn't always indicate there is a coral garden (VME) on the seabed. However, sometimes you will get a large number of gorgonians recorded as by-catch within the same area. This can lead you to think that there could be a high likelihood of a VME being present but we still can't explicitly say that." This has led to the group developing a weighting system.
The weighting system looks at the number of VME indicator records for a particular area (presented on the map as a 0.05°x 0.05° c-square, much the same as the VMS data). It evaluates how many records there are of particular VME indicators, where the indicators have come from, and the survey method used (trawl, longline bycatch or camera). This evaluation leads to a score as to the likelihood of a VME being present. On the new portal map, this will display as yellow for a low likelihood, orange for medium, and red for high. Records of known VME habitats are shaded blue. Golding feels this new weighting system will be extremely valuable to the group's work. "The group has been working on this for the last few years. In the past, when we have been requested to provide recommendations on bottom fishing closures to protect VMEs, it has been difficult to know how much confidence you have in the VME indicators. If it was a video transect then you have high confidence but if it was a bycatch of some coral then there might not be a VME down there. That's why this weighting system will be really important."
Displaying all VME data being used by the group ensures that all data underpinning WGDEC recommendations (such as bottom fishing closures) is now visible. "The key thing is that users can now see this. The portal represents the first time we have had these data out in the open. People can now click on the different VMEs and the different indicators. They can look at the recommendations made by WGDEC for bottom fishing closures, formal ICES advice which is provided to ICES clients, and the actual closures enacted by the regional fisheries management organisations. All this can be viewed on the one map as different layers. It makes the process so much more transparent. Advice clients and stakeholders can see what we're doing. I think it's really impressive."
All VME indicator data has been gridded using a 0.05° grid (the same grid that is used for VMS data), and presented via a map on the web portal. This will show the distribution of all VME indicator records being considered by WGDEC and all records will be available for download through the portal. Web services will also allow users to export data from the portal to their GIS.
The group emphasises that the current data portal is a beta version and some features, such as the weighting algorithm will not be live until next week (29 February). The data portal will remain as a beta version for the next four weeks. In this time, they request that all portal users send feedback. This can be to the Chair of WGDEC directly or using a pop up box that will appear on screen when using the map. The timeline for moving from the beta version to launching the final product is expected to be less than a few weeks, depending on the volume of comments received.
A coral garden VME on Anton Dohrn seamount. Photo by Joint Nature Conservation Committee (JNCC), UK, 2009.