Provides that designation of the Wilderness shall not be construed to prevent within the area's boundaries: (1) installation and maintenance of hydrologic, meteorological, climatological, or atmospheric data collection and transmission facilities when they are essential to the scientific research purposes of the Luquillo Experimental Forest; (2) construction and maintenance of nesting structures, observation blinds, and population monitoring platforms for threatened and endangered species; or (3) construction and maintenance of trails to such facilities as necessary for research purposes and the recovery of such species.