Thinning and regeneration in Puerto Rico's colorado forest, with comments about their effect on the Puerto Rican Parrot

A 50 % basal area reduction in Puerto Rico's colorado forest had little immediate impact on diameter at breast height growth for most residual stems. A slight positive response was evident for several species after 5 to 30 yrs. Instead, thinning served as a major stimulus for a massive ingrowth of two common colorado forest tree species important to the Puerto Rican Parrot: palo colorado (Cyrilla racemiflora L.), the major parrot nesting tree, and cupeillo (Clusia clusoides (Griseb.) D'Arcy), a main source of food. Canopy opening appeared beneficial for the survival and regeneration of laurel sabino (Magnolia splendens Urban), an uncommon tree used by the parrot for nesting and food. Other species that showed substantial increases in stem numbers were palo de hueso (Haenianthus salicifolius Grised.) and camasey (Miconia tetrandra (L.) DC).