Abstract/Summary

Numerous island species have gone extinct and many extant, but threatened, island endemics require ongoing monitoring of their conservation status. Until recently the small tree, Vachellia anegadensis, was thought to occur only on the limestone island of Anegada in the British Virgin Islands (BVI) and was assessed as Critically Endangered (CR). However, in 2008 it was discovered on the volcanic island of Fallen Jerusalem approximately 35 km from Anegada. To re-assess its conservation status and inform conservation interventions, we determined the distribution, genetic population structure, dependency on pollinators, suitable habitat and current threats of V. anegadensis. We showed V. anegadensis to be locally widespread on Anegada and sporadic on Fallen Jerusalem. We established that geographical location does not predict genetic differentiation amongst populations. We found that V. anegadensis produces more seeds when visited by animal pollinators, primarily butterflies. Introduced animals and disturbance by humans are the main threats to V. anegadensis indicating that in situ conservation is crucial for its long-term survival. Due to the newly discovered population on Fallen Jerusalem, we reassessed V. anegadensis as Endangered (EN).