Anton Dohrn biotope map

Translated from Anton Dohrn biotope maps showing all Annex I and non-Annex I habitats. Translated to EUNIS by JNCC.

Data collected aboard the MV Franklin in July 2009: Acoustics (Multibeam echosounder), Drop camera/towed video (10 sites).

The original survey plan (Stewart 2009) for the Anton Dohrn Seamount AoS involved a combination of radial transects on the top of Anton Dohrn and a suite of transects parallel to the flanks of the seamount both at the top of the flank and a level near the base the flank tohighlight the lower level of possible rock or hard substrate. 
The survey plan was subsequently modified to provide an area of multibeam coverage over two areas on the flanks of the seamount. The areas selected were on the south-eastern flank and the northwestern flank (Figure 5) and included diverse morphological features noted during the SEA 7 2005 survey (Jacobs 2006). The areas would provide a contrast between the south-eastern area primarily subject to ‘southern’ water masses and the north-western area occasionally influenced by ‘colder’ NSDW waters spilling over the Wyville Thomson Ridge. The two case study areas also differ in the height of the cliff surrounding the seamount. In the northwestern area the break in slope is at around 845m below sea level with the cliff descending to the moat at around 2195m depth, the slope levels off below 1700m at the foot of the cliff.
The south-eastern area shows a subtle break in slope at around 875m below sea level and a major break in slope at around 1100m below sea level before the cliff descends towards the centre of the moat at around 2300m water depth. The range of morphological features observed on the lower slopes of also differed.

Mapped habitats for Anton Dohrn Seamount attributed with Annex I reef type and biotopes. Each individual polygon may represent more than one Annex I habitat type so the column 'Annex_1_summ' in attribute table represents the overall Annex I habitat. 'Potential' is used when the habitat has been based purely on BGS mapped data, with no groundtruth data. 
Each polygon can also represent more than one biotope, and these have been coded as Biotope_1, 2, 3 and 4. Biotope1 is the main biotope for the habitat and this has been transcribed into an overall biotope column'biot_summ'. Substrates have also been classified as just 'muds', 'sands' or 'gravels' within the biot_summ column. This column should be used for creation of biotope maps.
Observed/predicted relates to whether seabed imagery was used to determine the habitat (observed) or whether it has been based on BGS data and extrapolation from nearby polygons (predicted).
Confidence scores relate to confidence in the data used to develop the map and have been determined as follows:
1. Polygons with both high res MBES (from 2009 survey) and camera drops
2. Polygons with high res MBES (2009) only
3. Polygons with low res MBES (from SEA7, 2005 survey) and camera drops
4. Polygons with low res MBES onlyfrom SEA7, 2005 survey.
The bedrock polygon around the seamount flank is split into 4 separate polygons(FID 58, 167, 169, 170)based on confidence levels relative to the regions of high and low MBES.

Additional information source:

Long, D., Howell, K.L., Davies, J., Stewart, H. & Golding, N. (Editor).  2010.  JNCC Offshore Natura Survey of Anton Dohrn Seamount and East Rockall Bank Areas of Search.  JNCC Report No. 437.

Tags: Corpulent, Drop camera, EUNIS, GB001134, Marine, Multibeam echo sounder, Nature Conservation, Seabed Habitats and Geology, Side scan sonar, Towed video
Organization: Joint Nature Conservation Committee