Arenillas Ecological Reserve

Arenillas Ecological Reserve () is a protected area in Ecuador situated in the El Oro Province, in the Arenillas Canton and in the Huaquillas Canton. 
Known mammals in the reserve, according to a 1993 study include the Sechuran fox ("Lycalopex sechurae"), the nine-banded armadillo ("Dasypus novemcinctus"), Robinson's mouse opossum ("Marmosa robinsoni"), the Pacific spiny-rat ("Proechimys decumamus"), the jaguarundi ("Puma yagouaroundi"), the tayra ("Eira barbara"), the greater bulldog bat, the common vampire bat ("Desmodus rotundus"), the crab-eating raccoon ("Procyon cancrivorus") and the Guayaquil squirrel ("Sciurus stramineus"). There are also 153 species of birds of which 35% are endemic. The reserve is a BirdLife International IBA with the following endangered birds: grey-cheeked parakeet ("Brotogeris pyrrhoptera"), slaty becard ("Pachyramphus spodiurus"), and blackish-headed spinetail ("Synallaxis tithys").
The region is managed by the ministry of defense and visitors must get permission from them to visit the area. 