A BBC report, with some satellite help from Oceanmind based @ Oxford, England; which is also available to Sierra Leone and at the end there is an answer of sorts:
investigates illegal and unsustainable fishing off the west coast of Africa to find out how one of the most fertile ecosystems on earth has been pushed to the brink.
Link:https://www.oceanmind.global/ and https://www.bbc.co.uk/news/av/world-...-africa-s-fish