Tree ferns of Central Veracruz : harvest and conservation implications
Tree ferns are listed as endangered species under Mexican law and the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES). Despite this status, tree ferns are currently being harvested by rural communities, and sold in the form of handicrafts, traditional medicines, and household ornaments In the state of Veracruz, some authors argue that the harvesting of tree fern caudexes (trunks) to obtain a material made out of the fern’s adventitious roots called maquique poses a major threat to tree fern conservation. This thesis systematically explores the effect of harvesting activities on the distribution of tree fern species in the tropical montane cloud forest’s fragmented landscape using vegetative regeneration as a proxy for maquique harvesting. The study was conducted in El Zapotal in the municipality of Acajete and El Riscal in the municipality of Coatepec, two small communities with different land use histories. A census was performed at each site to georeference and document all tree fern individuals, including information on diameter, height and presence/absence of vegetative regenerations due to maquique harvesting per individual tree fern. Four species were present in the study: Alsophila firma, A. tryoniana, Cyathea bicrenata, and C. fulva. ArcGIS Desktop was used to calculate distances from individual tree ferns to trails and rivers, which were regarded as points of access for maquique harvesters. These data were used to infer how and whether maquique affects the distribution and abundance of tree fern species at the two studied sites. This study reports for the first time different forms of vegetative regenerations in Mexican tree fern species such as the resprouting of multiple branches from a single tree fern trunk and also documents different forms of harvesting like the “C cut”. Contrary to common conservation arguments, the study shows that tree ferns can continue to thrive even after a severe environmental modification, such as forest clearing and the establishment of tree plantations. Other results suggest that maquique harvesters operating clandestinely are more likely to target tree ferns with maquique closer to points of access (trails or rivers) rather than according to size. In the long run, this pattern of tree fern harvesting could modify the distribution of tree ferns as they are displaced from areas closer to human access, despite the ability of some tree fern species to regenerate in highly disturbed environments. The discovery of tree fern regenerative properties offers potential for the management of certain tree fern species as umbrella species for conservation in central Veracruz. It suggests that maquique harvesting might be sustainable given careful management and government regulation based on scientific data.