Population structure and conservation of the coastal palm Coccothrinax borhidiana (Arecaceae) in the northwest of Cuba

Coccothrinax borhidiana is among the top 50 most threatened plants of Cuba. This palm is endemic to Punta Guanos-Punta Seboruco, Matanzas. Given the increase of gas-oil exploitation in the area where this palm population grows, the current situation of the species could be much more serious than what is known. We characterized the population structure based on a systematic sampling of 100 plots and evaluated the existing threats for re-evaluating its conservation status and proposing a recovery strategy. We sampled 685 individuals, 44.2 % juveniles and 55.8 % adults, whose population structure in 10 size classes did not conform to a log-normal distribution. This indicates that reproduction and/or recruitment processes are reduced, due to deforestation for the gas-oil industry, road construction and the establishment of small-holder, as well as the effect of cattle ranching and frequent fires. However, the higher representation of individuals in the three smaller size classes shows regeneration, which is observed in areas abandoned by the gas-oil industry. Despite this, existing threats have significantly reduced the area of occupancy of the species, and it is estimated that it will continue to decline by up to 80 %, making the species Critically Endangered. For these reasons, immediate management actions are needed to minimize the effect of threats on C. borhidiana, as well as to secure the management and implementation of ex situ conservation strategies that will allow the establishment of a new subpopulation in a nearby and ecologically similar area, which has the necessary legal protection status.