Although some of Hualālai is bare volcanic rock, most of it is covered by some form of vegetation. Bushes, ferns, and grass are common, and even a few ōhia lehua trees ("Metrosideros polymorpha") grow along the summit. Many of the collapse craters in particular have vegetation, and a few even have respectably-sized "vertical forests" inside, including several eucalyptus tree groves. The volcano is populated by many birds and animals; the coast in particular attracts many fish and sea-dependent animals, such as the green sea turtle ("Chelonia mydas") and the black-winged stilt ("Himantopus himantopus"). Hualālai averages of rainfall per year. The summit gets more rain than the coast and is typically obscured in heavy cloud cover and vog.