Tullow Ghana Limited (TGL) have been collecting opportunistic marine mammal and turtle sightings data in the Jubilee oil field and Tweneboa-Enyenra-Ntomme (TEN) fields from 2010 to 2018 (excluding 2012). Data has been analysed in annual sightings reports by Gardline Limited to support the TGL Environmental Impact Assessments issued to the Ghanaian government.

Gardline have run 5 marine mammal and turtle identification and observation techniques training courses (2x 2010, 2x 2013, 2017 and 2018), training over 50 people from TGL and Navy. The 2-3 day training course covered basic acoustics and its effect on marine animals, marine mammal and turtle ID and behaviours, completing sightings forms and observation and monitoring techniques.

Opportunistic data was collected by TGL and Navy personnel working on offshore platforms and security vessels. Observations were conducted in conjunction with monitoring for other objects e.g. fishing gear.

In the event of a marine animal sighting, observers completed a standardised form including the date and time, vessel position, species identification, number of individuals, behaviour and details of features used to identify the animals. Where feasible, photographs were taken

Species identification was verified by Gardline Marine Biologists and a level of certainty given – definite, probable or possible.

Results & Conclusions

  • Sightings dominated by dolphin species: 90% dolphin sightings, 11% turtle and 9% whale
  • 18 species of marine mammal recorded. 15 with definite identification, 3 probable
  • 1st known confirmed sightings of sperm whale in the area
  • 8 years of data collection have resulted in 929 sightings of marine mammals and turtles. This contributes to the largest dataset of marine mammal sightings for Ghanaian waters
View the poster presentation


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