and lakes, disrupted riparian systems, and poor water quality. In the National Parks Service's "Climate Action Plan," goals were set to reduce greenhouse gases 30 percent below 2008 levels by 2020 and plan and implement measures that best allow the park to adapt to the impacts of climate change. Strategies to accomplish these goals included: "reduce [greenhouse gases] emissions resulting from activities within and by the park, developing and implementing a plan to adapt to current and future impacts of climate change, increase climate change education and outreach, and monitor progress and identify areas for improvement". Biology and ecology Plants There are approximately 1,737 known species of vascular plants, 167 species of fungi, 64 species of moss, and 195 species of lichen found in Grand Canyon National Park. This variety is largely due to the elevation change from the Colorado River up to the highest point on the North Rim. Grand Canyon boasts a dozen endemic plants (known only within the Park's boundaries) while only ten percent of the Park's flora is exotic. Sixty-three plants found here have been given special status by the U.S. Fish and Wildlife Service. The Mojave Desert influences the western sections of the canyon, Sonoran Desert vegetation covers the eastern sections, and ponderosa and pinyon pine forests grow on both rims. Natural seeps and springs percolating out of the canyon walls are home to 11% of all the plant species found in the Grand Canyon. The canyon itself can act as a connection between the east and the west by providing corridors of appropriate habitat along its length. The canyon can also be a genetic barrier to some species, like the tassel-eared squirrel. The aspect, or direction a slope faces, also plays a major role in adding diversity to the Grand Canyon. North-facing slopes receive about one-third the normal amount of sunlight, so plants growing there are similar to plants found at higher elevations, or in more northern latitudes. The south-facing slopes receive the full amount of sunlight and are covered in vegetation typical of the Sonoran Desert. Animals Of the 90 mammal species found along the Colorado River corridor, 18 are rodents and 22 are bats. Life zones and communities The Park contains several major ecosystems. Its great biological diversity can be attributed to the presence of five of the seven life zones and three of the four desert types in North America. The