On the island of Príncipe a forest giant, known locally as the Obô snail, has undergone a population decline of more than 75% within the last 20 years and its range has decreased by approximately 40%, according to a recent report.
Príncipe lies in the Gulf of Guinea off the west coast of Africa and is the smaller of the two main islands that make up the nation of São Tomé and Príncipe. The island is a UNESCO Biosphere reserve, with much of its remaining native forest protected within the Parque Natural do Príncipe.
Between June 2018 and September 2019, a series of ecological and social surveys were carried out to find out more about the ecology of and threats facing Príncipe’s bird and terrestrial mollusc species. The surveys were carried out by the NGO Fundação Príncipe, along with local eco-guides and national park technicians, with technical input provided by Fauna & Flora International.
The surveys also uncovered six mollusc species that are new to science and two new records for Príncipe, but 16 previously recorded molluscs were not found during this set of surveys.
Across the survey period, just 119 live individuals were recorded. Once occurring throughout much of Príncipe, the Obô snail is now found across approximately 46 km2, restricted to the protected forests in the south of the island. The species was still abundant during the 1990s, so it is likely that this decline has happened over the last 20 years.