Fugro Worldwide Fugro Environmental

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3 Fugro Worldwide The Fugro group of companies is an international consulting company that provides measurements and interpretations of data related to the earth's surface and the soils and rocks beneath. On the basis of this data, the Company provides advice, generally for purposes related to the oil and gas industry, the mining industry and the construction industry. Focusing on providing solutions to its client's requirements, the group was created by the merger of Fugro and McClelland groups of companies. Fugro operates on a world-wide scale. The group employs over 12,000 people in over 275 offices world-wide and is headquartered in the Netherlands. Further information can be found on the Fugro website ( Fugro Environmental Fugro s Environmental Division s based in Great Yarmouth in the UK and comprises graduates from various disciplines including Oceanography, Marie Biology and Marine Chemistry. We perform specialist marine environmental surveys, specifically environmental baseline surveys, monitoring surveys, biotope (or habitat) mapping, marine mammal observation (also utilising Passive Acoustic Monitoring - PAMs) and desk study EIAs. Surveys are routinely peformed in the North West European Continental Shelf (NWECS), within the Arabian Gulf, the Mediterranean Our environmental scientists perform fieldwork operations including sediment and water sampling and video/ stills photography. Physicochemical analysis is subcontracted to accredited laboratories, whilst 3

4 Biotope Definition The biota interacting with the physical habitat: plants and animals found at a location together with their immediate physical environment. An area that is uniform in environmental conditions and in its distribution of animal and plant life. The terms biotope is almost synonymous with habitat expect that habitat refers to a species or population whilst biotope refers to a biological community Biotopes within biotope complexes e.g staghorn or boulder coral communties (biotope) within a coral reef (biotope complex) Nomenclature Provides an objective or semi-quantitative standardised naming system; Environment e.g. Marine or Terrestrial Bathymetric Zone/ wave exposure e.g. Littoral zone (L), sublittoral zone (SL) Habitat / Substratum e.g. Rock (R), Gravel/ Sands (GSD), Mixed Deposits (MXD) Life Forms e.g. Algal turf (ATRF), patch reef (PR), seagrass 4

5 Mapping Techniques Remote Sensing Satellite imagery Advantages: Able to view a large area within a very short period of time Relatively inexpensive Useful for land mapping Most useful in clear waters, specifically for seagrass/ coral reef mapping Disadvantages: Limited to shallow water and high visibility regions No information on seabed bathymetry i.e. local topography Quality can vary dependent upon which satellite used Aerial photography Advantages: Photographs provide a visual assessment of relatively remote areas; Orthophotographs provide a very highly accurate background layer; Photographs can often be found from the present day back to the 1940s, providing insights into habitat change. Disadvantages: Maximum water depths for bottom visibility are often <10 m (furthermore, few photos are taken under low-tide conditions); Sun glint and waves can render an image virtually useless and are a considerable nuisance for seamless mosaicking and interpretation. LIDAR (Light Detecting and Ranging) Aeroplane-mounted lasers determine the difference in distance between the waters surface and seafloor, with accurate positioning of the aeroplane, determining its height and location. Whilst primarily a topographic technique, recent developments have show useful results in using the strength of the returning signal to determine the roughness and hardness of the seafloor, similar to echosounder backscatter, which can be used as a proxy for seabed 5

6 Groundtruthing Methods Towed video/ stills photography/ drop down photography Reveals the physical nature of the seabed (e.g. sediment type); 1. The type of epifaunal communities associated with particular substrates (i.e. the variety of biotopes); 2. The distinctness of boundaries between different habitats/biotopes (e.g. discrete boundaries between rock and sand, or a gradual transition from sandy gravel to gravely sand); 3. The heterogeneity of habitats/biotopes within an area that appeared to be homogeneous to remote sensing techniques (e.g. on the acoustic base map); 4. The nature of the apparent boundaries observed by remote sensing techniques. 5. Can be semi-qualitative (video) or quantitative (stills) 6. Require good positioning system Eyeball ROV 1. Used to investigate specific areas as identified 6

7 Biotope mapping objective Mapping technique Allows stratified survey strategy to maximise survey efficiency (i.e. groundtruthing in select areas only) Enables priority areas to be investigated i.e. environmental sensitive areas as priority. Management tool Repeatable survey with objective criteria and quantifiable results Temporally and spatially comparable data Biotope maps are easily interpretable and visually accessible. 7

8 Survey Strategy Design using Satellite Data 1) Unsupervised classification: biotope boundaries are initially delineated based purely on data. Can be done either maunally or automated using spectral properties 2) Survey strategy devised: i. Camera transects ii. iii. Grab/ water sample stations Video Ray sites of special investigation 3) Supervised Classification: i. Healthy coral communties ii. iii. iv. Sparse coral and rock outcrops Seagrass beds Dead reef foreground with macroalgae overgrowth v. Clean rippled sands 8

9 Survey Strategy using Sonar Mosaics Similar approach can be taken using side scan sonar data. Data can either be mosaiced or manually mapped as A0 seabed features map. Photographs can be displayed alongside interpreted data. Video transects and subsequent ROV dives can be located according to different sonar returns. 9

10 Side Scan Sonar Groundtruthing Examples Example of high resolution sidescan sonar data with groundtruthed photographs of different biotopes 10

11 Survey Strategy using Multibeam Echo Sounder (MBES) Bathymetry Multibeam bathymetry showing camera transect with high resolution photographs along the line. MBES data can be used to identify areas for further groundtruthing using both towed video and stills photography and eyeball ROV. 11

12 Eyeball ROV Specific Applications A vital aspect of biotope mapping to add the last level of detail to the mapping process. The eyeball ROV allows a fine level of detail to be included into the map. i.e. video transects are necessary for delineating large areas and for identifying biotope changes (including transitional areas). High resolution digital stills photographs are useful as an easily accessible visual record Eyeball ROV dives are used to investigate specific areas on a small-scale. Eyeball ROVs are used for a full review of the marine populations comprising a certain biotope. Other factors can be identified e.g. coral health (disease, fish predation, diver damage), seagrass maturity (density, cohabiting species) We have used the eyeball ROV in two different configurations 1) Deployed from a RIB, using batteries and recording system. Advantageous where no power available (with generators not allowed on RIBs). Initially attempted to fly beside the RIB, but proved impossible Then was attached to a fixed deployment system and was used in towed mode. This also allowed up and down movement of the eyeball to view different aspects. 2) Deployed from a subsea garage A subsea garage was deployed (with a positioning beacon attached) and the ROV flown from here, attached to the garage by a 10-15m umbilical. 12

13 Example of the ROV used in a towed configuration in very shallow water over dead fringing reef. 13

14 ROV used to investigate horse mussel bed offshore Abu Dhabi. Trigger arm could be used to collect specimens if required. 14

15 ROV shown during a night dive. This allows 24 hour working operations and reveals the biotope at night. 15

16 ROV shown deploying from the subsea garage (also used as the camera housing). ROV is oriented to the rock outcrop as previously identified and flown there across a different biotope type. The ROV can be used for fish counts and detailed observations of macroalgae 16

17 ROV being used to identify small healthy coral communities found on a rock outcrop. 17

18 Summary 18