APPENDIX TOL-27 · APPENDIX TOL-27 RPS Energy’s Marine Mammal and Turtle Observer Report on 3d Baseline Seismic Survey Greater Jubilee Appraisal Area and Teak Development Area Offshore

APPENDIX TOL-27

RPS Energy’s Marine Mammal and Turtle Observer Report on 3d Baseline Seismic Survey Greater Jubilee Appraisal Area and Teak Development Area Offshore Ghana for Tullow Oil, 18

April-31 May 2013

Tullow Oil/EOM1499.1/MDB/JS/JG/df/df

MARINE MAMMAL AND TURTLE OBSERVER’S REPORT

ON 3D BASELINE SEISMIC SURVEY

GREATER JUBILEE APPRAISAL AREA AND TEAK DEVELOPMENT AREA

OFFSHORE GHANA FOR

TULLOW OIL

18th April to 31st May 2013 Report No. : EOM1499.1 RPS Energy, Nelson House,Author(s) : M. de Boer, J. Saulino Coombe Lane, Axminster, and J Griffiths Devon. EX13 5AX, UK. T +44 (0)1297 34656 F +44 (0)1297 33277Date : 20th September 2013 E [email protected] W www.rpsgroup.com

CONTENTS Title Contents Page Number

1. INTRODUCTION 1 1.1. SURVEY AND LOCATION 1 1.2. MITIGATION REQUIREMENTS 2

2. EQUIPMENT AND METHODS 4 2.1. VESSEL DETAILS 4 1.1. SEISMIC EQUIPMENT AND SOUND EMISSIONS 4 2.2. MMTO AND PAM SURVEY METHODS 4 2.3. PAM EQUIPMENT, DEPLOYMENT AND MONITORING PROCEDURE 6

2.3.1. Equipment 7 2.3.2. Deployment 7 2.3.3. Monitoring 7

3. RESULTS 8 3.1. OBSERVER EFFORT AND SIGHTING CONDITIONS 8

3.1.1. Undershoot Operations (20th May until 22nd May 2013) – Western Pride 8

3.2. DISTRIBUTION AND OCCURRENCE 9 3.2.1. Visual Sightings 9

3.2.1.1. Whales 9 3.2.1.2. Blackfish 9 3.2.1.3. Dolphins 10 3.2.1.4. Turtles 10 3.2.1.5. Observations of Other Wildlife 10

3.2.2. Acoustic Detections 11 4. COMPLIANCE WITH GUIDELINES 14

4.1. SOFT-STARTS 14 4.2. MITIGATION ACTION 14

5. CONCLUSIONS AND RECOMMENDATIONS 16 5.1. CONCLUSIONS 16 5.2. RECOMMENDATIONS 16

6. ACKNOWLEDGEMENTS 17

7. REFERENCES 18


APPENDICES APPENDIX 1 JNCC Guidelines APPENDIX 2 JNCC Recording Forms APPENDIX 3 Sightings Distribution Maps APPENDIX 4 Photographs of Sightings and PAM Screenshots APPENDIX 5 PAM Equipment and Deployment FIGURES FIGURE 1 Regional Setting of Jubilee Field FIGURE 2 Location of Prospect showing Location of FSPO TABLES TABLE1 Mitigation Measures Summary TABLE2 Seismic Source Summary TABLE 3 Marine Mammals and Turtles occurring in wider Gulf of Guinea TABLE 4 MMTOs and PAM Operators On Board Geco Eagle and Western

Pride TABLE 5 Marine Mammal and Turtle Sightings Summary observed from

Geco Eagle TABLE 6 Acoustic Detections TABLE 7 Summary of Mitigation Actions


1. INTRODUCTION 1.1. SURVEY AND LOCATION Marine Mammal and Turtle Observers (MMTOs) were embarked to the Geco Eagle to advise on the implementation of mitigation guidelines adopted by Tullow Ghana Limited (TGL) and Partners concerning seismic operations in Ghana waters. Observations of marine mammals, marine turtles, seabirds and fish were carried out by the MMTOs during a 3D baseline seismic survey in the in the Greater Jubilee Appraisal Area and in particular the Jubilee Unit Area (JUA) and the Teak Development Area (TDA) (please see FIGURE 1). The 3D survey was conducted by WesternGeco utilising the seismic survey vessel Geco Eagle in April/May 2013. The survey area comprised 71 sail lines (with an average length of 27 km), located approximately 45 and 65 km off the Ghana coast. The nearest port, Takoradi, is approximately 110 km from the prospect. One FPSO lies within the proposed survey area (FIGURE 2). The 3D baseline seismic survey covered approximately 650 km² and the water depths in the prospect (green polygon in FIGURE 1) varies from approximately 80 m at the northern edge to 1700 m at the most southern and outboard edge.

FIGURE 1 Regional Setting of Jubilee Field

Tullow Oil/EOM1499.1/MDB/JS/JG/df/df 1

FIGURE 2 Location of Prospect showing Location of FPSO

The continental shelf off Ghana creates 2 seasonal periods of coastal upwelling (major and minor) each year, with differing duration and intensities. During the upwelling, sea surface temperature (SST) drops, surface salinity increases and dissolved oxygen decreases. The major upwelling of nutrient-rich water (long cold season) occurs between July and September when SST (usually ~ 27–29 °C) falls below 25 °C. The minor upwelling (short cold season) normally lasts for only about 3 weeks (occurring anytime between December and March). In between the cold seasons are warm seasons during which SST is relatively high and a strong thermocline is formed in continental shelf waters. 1.2. MITIGATION REQUIREMENTS The guidelines used in this survey were the Joint Nature Conservation Committee (JNCC 2010) 2010 guidelines for monitoring of marine mammals and mitigation of impacts from seismic surveys (APPENDIX 1). These guidelines are also stated as being applicable to sea turtles. During transit to the prospect and at all times whilst on the prospect and during the hours of dawn till dusk, one MMTO was present on the bridge deck or monkey island (deck above bridge) of the survey vessel with a clear unobstructed view to the horizon. There were a total of 2 MMTOs aboard the seismic vessel, which allowed one MMTO to rest while the other was on watch. Clear communication channels between the MMTO and seismic observers were in place before commencement of the pre-shooting search. The MMTOs were made aware of the timings of the proposed operations so that there was adequate time to conduct the pre-shooting search. The survey was, for the majority, undertaken in deep water (JNCC classification > 200 m). In order to offer some protection to deep-diving species of marine mammals, it was therefore a


requirement to undertake a 60 mins pre-watch prior to any array activity (soft-start, gun tests etc). Following a standard 60 mins pre-watch the array was then increased to full power in incremental stages over a period of 20-40 mins (i.e. ‘soft-start’). An additional requirement was that ‘the operating seismic source will be terminated if the source is clearly causing stress to the animals (i.e. marine mammals and turtles) in close proximity to it or there is the likelihood of these animals passing directly under it’. Passive Acoustic Monitoring (PAM) was also deployed on the vessel as an ancillary monitoring technique, during all hours of darkness. Another additional requirement was the installation of ‘turtle guards’ on all tailbuoys in an attempt to negate the problem of turtle entrapment in this equipment, which often leads to injury or drowning. These guards were inspected at the start of the survey by the Lead MMTO. They are simple devices that act to physically exclude turtles from the tailbuoy undercarriage (http://www.ketosecology.co.uk/Turtle-Guards3.htm).

Source Mitigation Zone 500 m Pre-watch Period 60 mins Soft-start Length 20-40 mins Soft-start Delays Yes Shut Down Mitigation Not required unless ‘the source is clearly

causing stress to the animals (i.e. marine mammals and turtles) in close proximity to it or there is the likelihood of these animals passing directly under it’

Species Covered All marine mammals and turtles Special Requirements (1) Turtle guards fitted to tailbuoys Special Requirements (2) Passive Acoustic Monitoring (PAM)

deployed on the vessel as ancillary monitoring technique, covering all hours of darkness

TABLE 1 Mitigation Measures Summary


http://www.ketosecology.co.uk/Turtle-Guards3.htm

2. EQUIPMENT AND METHODS 2.1. VESSEL DETAILS The Geco Eagle was both source vessel and observational platform for the MMTOs. This vessel has an overall length of 94.8 m; normal acquisition speed of 4.7 knots and is owned and managed by WesternGeco. The vessel is registered/flagged in Panama. For the undershoot operations, the Western Pride acted as seismic source and the Geco Eagle was the recording vessel. The Western Pride has an overall length of 72.9 m and is also owned by WesternGeco and registered/flagged in Panama. The survey vessel was accompanied by 3 support vessels. The support vessels were acting as guard vessels for the towed equipment and assisted in informing local shipping and fishing traffic of the nature of the operation in the area. The support vessels were: Mainport Ash, East and the Marten Michiel. 1.1. SEISMIC EQUIPMENT AND SOUND EMISSIONS The Geco Eagle towed 2 source arrays, with 3 sub-arrays each, at a depth of 8 m. The arrays were fired in flip-flop mode and details are listed in TABLE 2. Twelve streamers of 7 km length were also towed. Separation between the streamers was 75 m and the streamer depth was 9 m.

Number of Airgun Arrays 2 Number of Airgun Sub-arrays 2x3 Number of Airguns (excluding in-water spares) 24x2 Maximum Operating Volume 4000 in³ Operating Pressure 2000 psi Shotpoint Interval 18.75m flip flop Maximum Source Output (zero to peak) 51.7 bar-m Maximum Source Output (peak to peak) 106 ± 1.56 bar-m Total Acoustic Energy 358253.6 joules Peak Frequency 213 Hz

TABLE 2 Seismic Source Summary 2.2. MMTO AND PAM SURVEY METHODS Teams of Marine Mammal and Turtle Observers (MMTOs) carried out observations during daylight hours (typically 05:45 - 18:30 LT) during all acquisition. Casual observations were also forwarded by the crews of all the 3 guard vessels. On the source vessel, the MMTO teams comprised 2 people working a 2 hrs on, 2 hrs off watch rota during all daylight hours. The only exception to this was when all vessel personnel were required to attend compulsory safety drills or meetings. However, during pre-watches, soft-starts and online one MMTO was always on watch. During a watch, the MMTOs scanned the sea with both the naked eye and with high quality binoculars with 8x43 magnifications. DSLR cameras with zoom lenses were also used to take photographs of marine fauna for further subsequent detailed identification checks and to provide visual reference material for the client. Most observational effort was made from the bridge


wings (18 m) and Monkey Island (20.5 m), paying very special attention when a soft-start was imminent in order to ensure that the entire mitigation zone around the array was clear of marine mammals and turtles. Range finder sticks were made (according to Heinemann, 1981) using measurements of height of platform above sea level; observer’s height to eye; and observer’s arm length. These range finder sticks were utilized to accurately determine the distance of marine mammals/turtles from the source vessel. Sighting cues used to locate marine mammals during watch effort included the following:

• Obvious sighting of backs and fins (or the heads and backs of turtles) • Obvious blows from larger whales • Splashes- often the initial cue for the presence of smaller cetaceans (also produced

by fish and other marine fauna) • Feeding seabird flocks/circling seabirds (which often associate with feeding

cetaceans) • Oily slicks at the surface - an indication of prior/recent feeding activity • Location of fronts and other oceanographic features where marine fauna often

congregate The seismic observers maintained a log of soft-starts and source operations, which was made available to the MMTOs, in order that the length of soft-starts, the time spent observing while the source was active, as well as the total duration of source activity could be calculated. Other information regarding array configuration and soft-start procedure was provided on request. A set of standardised JNCC recording forms was completed throughout the survey (APPENDIX 2). The forms comprised:-

1) Effort and location record forms (details of MMTO watches and environmental data) 2) Operation forms (airgun activity log – completed with data input provided by the

seismic observers) 3) Sightings record forms (details of each marine mammal/turtle sighting and a

separate log listing sightings of elasmobranches, i.e. sharks and rays) In addition, a log of seabird species and other fauna (fish species) was kept on a daily basis. Twenty seven species of cetaceans are believed to occur in the wider Gulf of Guinea region including fin, blue and sei whales, all classified as “Endangered” by the IUCN 2012 Red List. Leatherback, green, Olive Ridley, hawksbill and loggerhead turtles have been recorded nesting on beaches along the coast of Ghana and have also been encountered offshore. The Olive Ridley turtle is considered to be “Vulnerable” by the IUCN 2012 Red List, while green and loggerhead turtles are listed as “Endangered” and leatherback and hawksbill turtles are reported to be “Critically Endangered”. These species are listed on Appendix I of the Convention on International Trade in Endangered Species (CITES) and granted its highest level of protection. The waters off Ghana are generally used for migration between the coastal nesting grounds, and turtles have the potential to cross the prospect area on their migration.


Common Name Scientific Name Red List Status Antarctic Minke Whale Balaenoptera bonaerensis LC Sei Whale Balaenoptera borealis EN Bryde's Whale Balaenoptera brydei DD Blue Whale Balaenoptera musculus EN Fin Whale Balaenoptera physalus EN Humpback whale Megaptera novaengliae LC North Atlantic Right Whale Eubalaena australis EN Sperm Whale Physeter macrocephalus VU Dwarf Sperm Whale Kogia sima DD Cuvier's Beaked Whale Ziphius cavirostris LC Killer Whale Orcinus orca DD Melon-headed Whale Peponocephala electra LC Pygmy Killer Whale Feresa attenuata DD Short-finned Pilot Whale Globicephala macrorhynchus DD False Killer Whale Pseudorca crassidens DD Risso's Dolphin Grampus griseus LC Rough-toothed Dolphin Steno bredanensis LC Common Bottlenose Dolphin Tursiops truncatus LC Pantropical Spotted Dolphin Stenella attenuata LC Atlantic Spotted Dolphin Stenella frontalis LC Spinner Dolphin Stenella longirostris DD Clymene Dolphin Stenella clymene DD Striped Dolphin Stenella coeruleoalba LC Long-beaked Common Dolphin Delphinus capensis DD Short-beaked Common Dolphin Delphinus delphis LC Fraser's Dolphin Lagenodelphis hosei LC Atlantic humpbacked dolphin Sousa teuszii VU Green Turtle Chelonia mydas EN Leatherback Turtle Dermochelys coriacea CR Hawksbill Turtle Eretmochelys imbricata CR Olive Ridley Turtle Lepidochelys olivacea VU Loggerhead Turtle Caretta caretta EN

TABLE 3 Marine Mammals and Turtles occurring in wider Gulf of Guinea LC = Least Concern; DD = Data Deficient; VU = Vulnerable;

EN = Endangered; CR = Critically Endangered

Literature sources: Weir, 2011; van Waerebeek et al, 2009; Tanner 2013 2.3. PAM EQUIPMENT, DEPLOYMENT AND MONITORING PROCEDURE Passive Acoustic Monitoring (PAM) for acoustic detections of marine mammals took place between 18:00 and 06:00 UTC, in order to cover operations during the hours of darkness. The PAM system was set up and deployed from the Geco Eagle on 3rd May 2013, approximately 12 days after the commencement of the survey. The delay was the result of


logistical problems in the delivery of the PAM equipment to the vessel. The PAM system used was supplied by Seiche Instruments UK. 2.3.1. Equipment The PAM system consisted of a standard 4 channel towed hydrophone array on a 250 m deployment cable with a depth gauge. An additional deck cable was run from the deployment cable to the streamer deck control room, the ‘cyberbase’ where the monitoring equipment was set up. A complete back-up PAM system was also available and on the vessel. The hydrophone array elements enable detection at high frequency, 2 – 200 kHz, and low frequency, 10 Hz – 24 kHz and allow for the calculation of bearings. An electronics processing unit and 2 laptop computers ran PAMGuard software programmes to detect cetaceans. A GPS feed from the vessel enabled the tracking of vessel movements and the plotting of detections. Monitoring was carried out on 2 laptop computers one laptop using a “Fireface 800” sound card, utilising spectrogram and click detector programmes to visually display medium and low frequency cetacean whistles, echolocation clicks and burst pulse sounds. Using a National Instrument sound card high frequency clicks from species such as beaked whales were tracked on the second laptop. The PAMGuard programme also allows a seismic veto to be introduced to filter out the seismic source and enable listening during times that the seismic source is in operation. The operator can listen through headphones to the sound in its raw or filtered state. 2.3.2. Deployment The seismic team and the PAM operator rigged the hydrophone for deployment from a reel on the starboard side of the streamer deck of the Geco Eagle. The cable was attached by rope to a strong fixing point and deployed to approximately 200 m from the stern, thereby being positioned midway between the seismic source and the vessel and offering the lowest risk of conflict with any seismic equipment. At the usual survey speed of around 4 to 5 knots the hydrophone array maintained a depth of approximately 17 m. After deployment the deck cable and the PAM system were connected. It was not necessary to recover the hydrophone until survey completion. Please see APPENDIX 5 for PAM equipment set up pictures. It was necessary to recover the hydrophone on 2 occasions to facilitate work on the streamers and on one occasion to untangle it from the streamer lead-in. Otherwise the system remained deployed and continuously recording until survey completion on 31st May 2013. On recovery some damage was evident on the array cable due to contact with the paravane or lead-in. 2.3.3. Monitoring The PAM operator monitored between the hours of 18:00 and 6:00 UTC, with particular attention to all pre-line watch periods in the hours of darkness. A continuous recording from the PAM hydrophones was saved to hard drive throughout operations; including all daylight hours. By recording during daylight hours it was possible for the PAM operator to review recordings and match possible detections with visual sightings; this aids in species identification and assists in the calibration of the range of the system. Communication between the seismic instrument room and the PAM station was maintained by internal telephone or VHF radio. Details of all operations including undershoot operations were passed to the PAM operator in good time. The seismic crew also confirmed full details of the relevant times from their operations log at the end of each day. Screen shots were taken of detections, please see APPENDIX 4. The relevant JNCC datasheets were completed with details of all PAM effort, detections and seismic operation times to be included with the MMTO data sheets.


3. RESULTS 3.1. OBSERVER EFFORT AND SIGHTING CONDITIONS Two Marine Mammal and Turtle Observers (MMTOs) and one Passive Acoustic Monitoring (PAM) Operator were present onboard the Geco Eagle throughout the survey (TABLE 4).

Geco Eagle Western Pride Name Dates Name Dates

Marijke de Boer (Lead MMTO)

18/04/13 – 31/05/13 Sue Travers (MMTO)

19/05/13 – 22/05/13

James Saulino (MMTO)

18/04/13 – 31/05/13 Lorenzo Scala (PAM)

19/05/13 – 22/05/23

Jane Griffiths (PAM)

18/04/13 – 31/05/13

TABLE 4 MMTOs and PAM Operators On Board Geco Eagle and Western Pride The Geco Eagle departed Takoradi on 18th April 2013 and visual observations by the MMTOs began immediately following departure. Deployment of the seismic gear started on 18th April 2013 and the seismic survey finished on 31st May 2013. During this time period 548 hrs 25 mins of dedicated observation for marine mammals and turtles were carried out by the MMTOs. 86.1% of the observations were carried out during periods when viewing conditions were favourable, i.e. glassy sea or slight state (Beaufort 3 or less), low swell, good or moderate visibility and no strong forward glare. Of the time spent watching, the source was active for 215 hrs 51 mins (39.4%). Although the survey commenced on 22nd April, PAM was not available until 3rd May 2013. To provide cover during the period that PAM was not operational the Geco Eagle seismic team used the in-streamer ‘Whale Watch’ system installed by WesternGeco. The PAM operator was available to confirm any detections made by the whale watch system which emits an audible warning if a detectable cetacean, that being one that is within the systems limited range, is in the mitigation zone. The system is still ‘in development’ and made no detections during the pre-line watches in the hours of darkness. A total of 211 hrs 30 mins of PAM was carried out from 3rd May to 31st May 2013. Time monitoring with seismic source active was 65 hrs 46 mins (31%) and with the source inactive 155 hrs 44 mins (69%). The survey area had a number of installations, vessels and sub-sea equipment producing varying levels of background noise, picked up by the PAM system when the survey vessel was in their vicinity. The PAM hydrophone was not affected by the prevailing weather conditions, although during vessel turns with strong current conditions, increased levels of water noise were heard. However, conditions were mostly considered satisfactory for acoustic monitoring with relatively low levels of background noise. 3.1.1. Undershoot Operations (20th May until 22nd May 2013) – Western Pride Three days of undershoot operations were carried out, using the Western Pride as the seismic source vessel. During this period (20th to 22nd May), the Western Pride carried out dedicated observations for marine mammals and turtles for a total of 40 hrs 30 mins. The majority of the observations were carried out when the sea state was slight and not choppy (95.1%). In total 24 hrs and 29 mins of PAM were carried out from the Western Pride.


Completed recording forms for observer effort, records of operations, sightings and acoustic detections are provided for both the Geco Eagle and the Western Pride in APPENDIX 2. 3.2. DISTRIBUTION AND OCCURRENCE 3.2.1. Visual Sightings A total of 110 cetacean and 22 turtle sightings were made, comprising a minimum of 5154 animals (TABLE 5). However, this number was almost certainly an underestimate, as it was difficult to estimate group size of distant sightings accurately, when only those animals seen breaking the water surface could be counted. Seven species of cetacean were positively identified: short-finned pilot whale, melon-headed whale, Pantropical spotted dolphin, Fraser’s dolphin, Delphinus spp (long-beaked common dolphin), rough-toothed dolphin (probably) and bottlenose dolphin. Where the confidence of species identification was not definite, the sighting was assigned to a more general species grouping, such as baleen whale, Stenella sp. or Spinner/Clymene dolphin, or small blackfish sp (either melon-headed or pygmy killer whale). Twenty-two sightings of turtles were made, including 3 species: Olive Ridley turtle, green turtle and leatherback turtle. During the undershoot operations, the Western Pride recorded 3 sightings of 33 marine mammals. These included one baleen whale sp and 2 sightings of 32 short-finned pilot whales. Maps of the spatial distribution of sightings are included in APPENDIX 3. 3.2.1.1. Whales Three sightings were made of whales. The first whale, identified as baleen whale sp. was seen from the Western Pride at a distance of 800 m from the vessel. Only the column-shaped blow and back were seen, and that hampered the identification to species. Another baleen whale was observed from the Geco Eagle on 25th May. Later that day, one more whale sp. was observed at a distance of 4 km. 3.2.1.2. Blackfish The group of so-named “blackfish” comprises long - and short-finned pilot whales, false killer whales, melon-headed and pygmy killer whales. All but the long-finned pilot whale can potentially be encountered in the region, but during the survey only short-finned pilot whales and melon-headed whales were positively identified. Short-finned pilot whales were encountered on 35 occasions, totalling 420 whales. These whales prefer deep water and they were typically encountered in waters ranging from 482 m to 4000 m (mean 1172 m; SD 615.34). On 11 occasions these whales were observed within the mitigation zone and on 2 occasions when the guns were firing at full power (distance to guns 400 m and 220 m). Responsive behaviours of these whales included course change and change in travel speed. For example, the pilot whales that approached to within 220 m from the arrays rapidly changed their heading, increased travel speed and soon raised their tailstocks which is generally indicative prior to a deep dive. One additional sighting was made from the Western Pride, on 22nd May, involving a group of 30 pilot whales which passed the vessel at close distance whilst the gun arrays were in operation. The majority of the whales passed ahead of the Western Pride, but several small sub-groups (4-6 individuals) quickly passed close to the arrays (at a closest distance of 35 m) showing no change in behaviour. Bottlenose dolphins occasionally accompanied pilot whales which is not uncommon. On 2 occasions the bottlenose dolphins were observed to come to ride the bow of the Geco Eagle


whilst the pilot whales were on a deep dive. Once the pilot whales had re-surfaced the bottlenose dolphins would swim away from the vessel to approach the pilot whales. Fourteen sightings were made with melon-headed whales involving a total of 2675 animals. These small whales also prefer deep waters and were seen at a depth ranging between 1223 m and 1494 m. This species is known to associate with Fraser’s dolphin which was observed on 3 occasions (Sighting 28, 40 and 118). 3.2.1.3. Dolphins Five different species of dolphins were positively identified: bottlenose dolphin, pantropical spotted dolphin, Delphinus spp (long-beaked common dolphin), rough-toothed dolphins and Fraser’s dolphins. However, in 35 cases (62 % of all dolphin sightings) the dolphins could not be positively identified to species because the groups either did not approach the vessel closely enough or the sighting was too brief. Fraser’s dolphins are a poorly known species which until the early 70s had not even been documented. They are a little known tropical species and within the Atlantic Ocean the published numbers of sightings of Fraser’s dolphins are in the low tens. During the survey a total of 6 sightings involving Fraser’s dolphins were made involving large groups of up to 350 dolphins (Sightings 93 and 94), further, they were observed in feeding activities/chasing prey and associating with melon-headed Whales. Both whales and dolphins were actively circling a confined area of prey with the dolphins concentrating in the centre of the area and the melon-headed whales on the edge. Bottlenose dolphins were seen on 5 occasions involving 30 individuals. On 3 occasions they were associating with pilot whales and, as previously stated, approached the Geco Eagle to bow- or wake-ride. They were very active and acrobatic, making frequent high leaps. Pantropical spotted dolphins were sighted on 3 occasions (Sighting 38, 52 and 127) whilst the vessel was not in production. One encounter involved a mixed group of dolphins, but unfortunately only the pantropical spotted dolphin was positively identified. The long-beaked common dolphin (Delphinus spp) was sighted on 3 occasions (Sighting 32, 101 and 107). The first encounter involved a group of 12 dolphins that were very surface active and were frequently breaching. The second encounter numbered 7 dolphins that were travelling very fast and briefly approached the bow of the Geco Eagle. The third encounter involved a large group of at least 50 dolphins that were observed in 2 sub-groups and were very surface active (frequently breaching to heights of 4 m+). On one occasion, a small mixed-group of probably rough-toothed dolphins and Stenella/ Delphinus sp. were identified. The dolphins were seen at a distance of 800 m from the Geco Eagle. 3.2.1.4. Turtles Three species of turtles were identified: Olive Ridley turtle, green turtle and leatherback turtle. The majority of the turtle sightings were ‘hard-shelled’ turtles but remained unidentified due to the fact that they were only briefly seen or were too far away to allow positive identification. The majority of the turtle sightings were made on 6th May when the ocean was glassy, and unusually, there were many small mats of Sargassum algae seen floating at the surface. 3.2.1.5. Observations of Other Wildlife Seabird numbers were generally low in the survey area.


Cory’s shearwaters and Tern species (Arctic or common terns) were seen on most days. Pomarine, Arctic, and great skuas were also identified, of which the Pomarine skua was most frequently seen. Storm petrels (mostly Wilson’s petrels) were seen in low numbers throughout the survey and were often not identified to species level due to the sighting distances involved. Two unexpected sightings were made involving a brown booby and a flock of 8 cattle egrets. Other species encountered included swifts, swallows, an African Wattled lapwing and a whimbrel. The only fish species observed regularly, i.e. every day, was the flying fish. Other fish species were only seen infrequently, including tunas of varying sizes (yellow-fin tuna and skip-jack tuna) and Atlantic triple fish. The latter was often associated with either aggregations of Sargassum algae or floating debris. Two white fish (as yet unknown species) were observed close to the port bow riding the shell of a turtle. 3.2.2. Acoustic Detections Between 13th May and 31st May 2013, a total of 19 acoustic detections of cetaceans were made. These were all whistle type detection events made on the medium frequency detectors, 2 – 24 kHz. Several of these events lasted for more than 5 mins with a number of animals present. Three detections were made online with the seismic source active. Seven detections were made following information on visual sightings made by the MMTOs during daylight hours. In these cases it was usually possible to confirm the species identity. Other detections were noted as dolphin type whistles using maximum and minimum frequency identification information (Oswald et al, 2007). There were no delays to operations during the hours of darkness from marine mammals. One detection was made in the 1 hr pre-watch period but the animals had left the mitigation area 20 mins before the commencement of the soft-start. TABLE 5 provides a summary of detections and APPENDIX 2 has full details of all detection events.


Species No. of Sightings

Total No. of Animals (Minimum Estimates)

Sighting Rate, No. of Sightings/

Hour*100 Short-finned Pilot Whale 35 420 6.38 Melon-headed Whale 14 2675 2.55 Bottlenose Dolphin 5 30 0.91 Rough-toothed Dolphin 1 18 0.18 Fraser’s Dolphin 6 980 1.09 Pantropical Spotted Dolphin 3 238 0.55 Common Dolphin (Delphinus spp) 3 67 0.55 Stenella sp. 2 45 0.36 Small Blackfish sp. 2 5 0.36 Large Dolphin sp. 7 37 1.28 Small Dolphin sp. 2 27 0.36 Dolphin sp. 25 577 4.56 Baleen Whale sp. 1 1 0.18 Whale sp. 4 11 0.73 Green Turtle 1 1 0.18 Olive Ridley Turtle 2 2 0.36 Leatherback Turtle 1 1 0.18 Turtle sp. 18 18 3.28 Total 132 5154 24.07

TABLE 5 Marine Mammal and Turtle Sightings Summary observed from Geco Eagle


Ref Date Species/ Group

Sounds Detected

Range (m)

Source Status

Visual Sighting

Ref Geco Eagle Acoustic Detections

501 07/05/2013 Dolphin sp Whistles <900 Active 502 08/05/2013 Dolphin sp Whistles 350 Off 71 503 08/05/2013 Dolphin sp Whistles 500 Active 504 09/05/2013 Dolphin sp Whistles 800 Off 505 12/05/2013 Dolphin sp Whistles <900 Active 506 13/05/2013 Bottlenose

dolphin Whistles, echolocation clicks

400 Off 85

507 13/05/2013 Dolphin sp Whistles, echolocation, burst pulse clicks

200 Off

508 14/05/2013 Dolphin sp Whistles 900 Off 509 15/05/2013 Dolphin sp Whistles 600 Off 510 16/05/2013 Dolphin sp Whistles 300 Off 511 16/05/2013 Dolphin sp Whistles 600 Off 91 512 16/05/2013 Dolphin sp Whistles 400 Off 513 20/05/2013 Short-finned

pilot whale Whistles/clicks 600 Off 102

514 21/05/2013 Short-finned pilot whale

Whistles/clicks 600 Off 103

515 22/05/2013 Long-beaked common dolphin

Whistles

500 Off 107 516 22/05/2013 Dolphin sp Whistles 600 Off 517 23/05/2013 Dolphin sp Whistles 600 Off 518 25/05/2013 Dolphin sp. Whistles 1000 Off 519 26/05/2013 Bottlenose

dolphin Whistles 400 Active 124

Western Pride Acoustic Detections

501 21/05/2013 Pilot whale Whistles buzzes 600 Off 502 21/05/2013 Dolphin Whistles 700 Off 503 21/05/2013 Dolphin Whistles 700 Off

TABLE 6 Acoustic Detections


4. COMPLIANCE WITH GUIDELINES 4.1. SOFT-STARTS On 7 occasions the period between the start of the soft-start (SS) to the start of line (SOL) exceeded 40 mins:

1) On 22nd April, there occurred a full-power gun test which followed the SS and lasted until the SOL. This is in compliance with the guidelines.

2) On 26th April, the Geco Eagle had to reduce speed to allow fishing vessels to clear

from the area. As a consequence the period between the start of SS to SOL was 42 mins.

3) On 10th May this period was 42 mins (Soft Start at 11:09 UTC). This was due to

stronger than expected currents; the vessel had to slow down more than expected, causing the time to exceed 40 mins.

4) On 12th May this period was 41 mins (Soft Start at 08:11 UTC). This was due to

stronger than expected currents; the vessel had to slow down more than expected, causing the time to exceed 40 mins.

5) On 13th May this period was 41 mins (Soft Start at 02:00 UTC) due to stronger than

expected currents, the vessel had to slow down more than was initially anticipated, causing the time to exceed 40 mins.

6) On 15th May this period was 59 mins (Soft Start at 08:11 UTC). This was due to a

failure in the streamer recording and control systems which meant that the entire system had to be rebooted and required the vessel to reduce speed to a minimum.

7) During the undershoot operations on 21st May 2013 (06:00 LT) this period was 41

mins. This was due to the fact that the vessel Western Pride had to slow down in order to match the speed of the Geco Eagle.

4.2. MITIGATION ACTION Marine mammals were present within the mitigation zone during a pre-watch on 5 occasions upon which a delay in firing was implemented.

1) On 23rd April a delay in firing of the guns (gun-test) was requested because marine mammals were present within the mitigation zone during the pre-watch (Sighting 12 and 13). However, the gun test was later cancelled for other operational reasons.

2) On 29th April a delay in soft-start was requested due to the presence of marine

mammals in the mitigation zone during the pre-watch (Sighting 31). Consequently, the vessel slowed down and a full soft-start was carried out 20 mins after the marine mammals had cleared the mitigation zone, prior to the SOL.

3) On 5th May a delay in soft-start was requested due to the presence of dolphins within

the mitigation zone during a pre-watch (Sighting 52). The dolphins stayed within the zone for 2 mins before moving on. The vessel slowed down and a full soft-start was carried out 20 mins after the dolphins had cleared the mitigation zone, prior to the SOL.

4) On 13th May, a delay in soft-start was requested due to marine mammals within the

mitigation zone during the pre-watch (Sighting 84 and 85). The marine mammals


stayed within the zone for quite some time (> 20 mins). They eventually left the zone but then re-entered on several occasions. Due to excellent communication with the instrument room, the vessel slowed down sufficiently to give the marine mammals 20 mins clearance after they were last seen within the mitigation zone (at 10:08 LT) as stated in the guidelines. The soft-start was then initiated at 10:28 and the Start of Line at 10:53 with no loss of production.

5) On 24th May, a small sub-group of melon-headed whales entered the mitigation zone

during the prewatch (Sighting 118). As a consequence the scheduled gun-test was delayed by 20 mins following the departure of the melon-headed whales from the mitigation zone.

Sighting Ref.

Date Species Range (m) Mitigation Action Required

12 and 13 23/04/2013 Short-finned pilot whale and bottlenose dolphin

450 m and 300 m Delay of gun-test

31 29/04/2013 Dolphin sp. 350 m Delay of soft-start 52 05/05/2013 Pantropical

spotted dolphin 350 m Delay of soft-start

84 and 85 13/05/2013 Short-finned pilot whale and bottlenose dolphin

350 m and 350 m Delay of soft-start

118 24/05/2013 Melon-headed whale

450 m Delay of gun-test

TABLE 7 Summary of Mitigation Actions


5. CONCLUSIONS AND RECOMMENDATIONS 5.1. CONCLUSIONS From the observations made by the MMTO’s during the survey it appears that the waters off Ghana hold a rich and varied marine fauna with a total of 7 species of cetacean and 3 species of marine turtle recorded. The authors did expect to encounter other cetacean species during the present survey however this was probably influenced by the warm season. Elsewhere in the Gulf of Guinea (e.g. Gabon) the cetacean community changed following the start of the cold upwelling season in late June/July (De Boer, 2010). Other species expected to occur in the region include Bryde’s whale, sperm whale and tropical dolphins such as the Clymene dolphin. The survey was considered successful at minimising the risk of disturbance and injury to marine mammals from the seismic surveys and complied fully with all current JNCC guidelines. 5.2. RECOMMENDATIONS The Gulf of Guinea forms a year-round breeding ground for larger whales (for humpbacks in the boreal summer and sperm whales in the boreal winter). Therefore, shut down mitigation would be an additional useful tool, adding some further protection especially to slow moving whale calves.


6. ACKNOWLEDGEMENTS The Geco Eagle and her crew provided an excellent platform for our work and the MMTOs and PAM operator would like to thank everyone concerned for their cooperation throughout the survey. Special thanks to the seismic crew who made every effort to work with the MMTOs/PAM in fulfilling the marine fauna mitigation guidelines adopted during this survey. The MMTOs/PAM would also like to thank the crew of the East, Marten Michiel and Mainport Ash for their valuable assistance in occasionally reporting marine mammal and turtle sightings via VHF radio.


7. REFERENCES De Boer (2010) Cetacean distribution and relative abundance in offshore Gabonese waters. Journal of the Marine Biological Association of the United Kingdom. 90(8), 1613–1621 JNCC (2010). Guidelines for Minimising Acoustic Disturbance to marine mammals from seismic surveys. Joint Nature Conservation Committee, Peterborough. Heinemann, D. (1981). A range finder for pelagic birds censusing. Journal of Wildlife Management 45(2): 489-493 Tanner C (2013). Sea Turtle Conservation in Ghana’s Western Region: The Bigger Picture. Marine Turtle Newsletter 136:9-12, © 2013 Oswald, J., Rankin, S., Barlow, J. and Lammers, M. (2007) A tool for real-time acoustic species identification of delphinid whistles, Journal of the Acoustical Society of America, Vol. 122, Issue 1, p 587-295.

Van Waerbeek K et al. (2009). The cetaceans of Ghana, a validated faunal checklist. West African Journal of Applied Ecology, Vol. 15: 61-90. Weir CR (2011). Ecology and conservation of cetaceans in the waters between Angola and the Gulf of Guinea, with focus on the Atlantic humpback dolphin (Sousa teuszii). PhD thesis, University of Aberdeen, Aberdeen.


http://asadl.org/jasa/

http://asadl.org/jasa/resource/1/jasman/v122

http://asadl.org/jasa/resource/1/jasman/v122

http://asadl.org/jasa/resource/1/jasman/v122/i1

APPENDICES Please select the following links: APPENDIX 1 - JNCC Guidelines APPENDIX 2 - JNCC Recording Forms APPENDIX 3 - Sightings Distribution Maps APPENDIX 4 - Photographs of Sightings and PAM Screenshots APPENDIX 5 - PAM Equipment and Deployment


Documents

APPENDIX TOL-27 · APPENDIX TOL-27 RPS Energy’s Marine Mammal and Turtle Observer Report on 3d Baseline Seismic Survey Greater Jubilee Appraisal Area and Teak Development Area Offshore