The elfin-woods warbler (Dendroica angelae), or reinita de bosque enano (Spanish name), is a bird endemic to the Caribbean island of Puerto Rico where it is a local and uncommon species. Discovered in 1968 and described in 1972, it is the most recently described species of New World warbler (family Parulidae). The species name, angelae, is a tribute to Angela Kepler, one of its discoverers. It is an insectivore, feeding by gleaning small insects off leaves and foraging the middle canopy for insects. Its song and call are difficult to hear, described as "a single, short, metallic chip". The elfin-woods warbler breeds from March to June, and both parents are involved in the construction of the nest and in feeding the chicks.
Due to its small populations and restricted habitats, conservation efforts were begun in 1982 to protect this species but, as of 2005, the warbler was still in need of protection. The species is not in immediate danger as the majority of its habitat is protected forest, but introduced species, such as rats and mongooses, habitat reduction, and natural disasters represent potential threats to the population, with last estimates pointing to 600 mature individuals. (more...)