Re-evaluation of the conservation status of the genus elaeocarpus in Sri Lanka

Abstract

Elaeocarpaceae, a family with 12 genera, is represented in Sri Lanka by a single genus Elaeocarpus. The island harbours nine species, eight endemics, and five are listed under various threat categories in the National Red List 2020. However, extensive fieldwork on this genus has not been carried out after the revision of the genus in 1995. Hence, the study aimed to re-evaluate the conservation status of the genus Elaeocarpus employing recent field-collected data from 2019-2022. Forty-five sites were visited, and the GPS locations were recorded. The sites comprised Forest Reserves, Sanctuaries, Strict Nature Reserves and Wildlife Parks, which were selected by referring to literature, including any other possible locations of occurrence. The potential distribution maps were developed by plotting the GPS locations on a map using ArcGIS 10.4 and were used in calculating the Extent of Occurrence and Area of Occupancy. The species evaluations were based on either criterion B or C of the IUCN guidelines 2019. According to the results, the conservation status of six species; E. ceylanicus as Critically Endangered (CR); E. coriaceus and E. hedyosmus as Endangered (EN); E. glandulifer and E. subvillosus as Nearly Threatened (NT) and E. serratus as Least Concern (LC) remained unchanged as given in National Red list 2020. However, with the updated information on the distribution and threats, three endemic species were upgraded; E. amoenus from NT to CR, E. montanus from Vulnerable (VU) to EN and E. taprobanicus from EN to CR. The uplifted threat status would facilitate these taxa to gain priority in conservation plans as the Red List, and its assigned threat status provide baseline information on the healthiness of a country's biodiversity and convey the urgency of conservation issues to the public and policymakers. Furthermore, the study highlights the importance of recent field-based information in determining the threat categories, which is pivotal for all other conservation acts.