An expedition into the rainforests of Sierra Leone resulted in the rediscovery of the Sierra Leone crab, which hasn’t had a confirmed sighting since 1955. In addition to this magical rediscovery, a species of freshwater crab which had been lost to science since 1796 was found, as well as two new crab species being discovered.
The expedition took place in the northern, southern and southeastern provinces of Sierra Leone in West Africa and lasted for 23 days throughout mid-January to early February during 2021. Pierre A. Mvogo Ndongo, a lecturer and researcher from the Department of Management of Aquatic Ecosystems of the University of Douala in Cameroon led the search.
The first discovery was made at a water source, not far from a local farm on the edge of a humid rain forest. It was here that Ndongo found the species of crab known as the ‘Afzelius’s crab’, which hadn’t had a confirmed sighting in over 225 years. Upon extending the search further, Mvogo Ndongo and his team found a number of other Afzelius’s crabs at the same site, indicating that, at least in that location, there was a seemingly healthy population.
On the very last leg of the expedition Mvogo Ndongo traveled to the forested Sugar Loaf Mountain, in a last attempt to find the Sierra Leone crab. Thanks to a tip from a member of the local community, Ndongo travveled to the destination site, around a three hour walk from ‘Guma Lake’ within the western Area National Park. Finally after a long journey he found the rare Sierra Leone crabs, burrowed deep in the forest, the first sighting since 1955. The crabs boast a beautiful and brightly coloured shell, which is pictured above.
“In the four days searching the dense forests on Sugar Loaf Mountain, I was able to find six specimens of the Sierra Leone crab because I was able to recruit local people to go into the forest and search with me,” said Mvogo Ndongo. “When I found the Sierra Leone crab, I was very very happy. This was after almost three weeks of searching for lost species.”