Many times the natural resources that attract tourists are in rural areas where jobs are scarce. Tourism creates immediate jobs because tourists need things like accommodations, food and transport.
These countries can benefit from a sudden influx of tourists who might otherwise not have visited. Ecotourism generates immediate business opportunities for the country and specifically for the area where the natural resource is situated.
The money tourists spend in restaurants and for lodging and other services has a direct impact in the vicinity of the natural resource site they visit.
Other businesses in the area benefit in turn from what is spent in restaurants, hotels and inns. The money stays in the area.
Workers spend their wages at various businesses in the area. Again, the money stays home, so to speak, creating more wealth locally.