Located in a global hotspot for biodiversity, Los Angeles County is home to more than 4,000 distinct species of plants and animals, including 52 endangered species — more than any county outside of Hawaii. And with 1 million animal and plant species facing extinction due to human activity, according to the United Nations, efforts to better understand the factors that shape biodiversity in Los Angeles could help shape global conservation efforts.
UCLA researchers today published the Biodiversity Atlas of Los Angeles, which will help scientists and residents alike better understand Los Angeles' unique environment and see how native, nonnative and endangered species are distributed across the county. Users can enter any street address in the county and visualize, for example, how likely they are to come across a mountain lion or black bear.
"The public should learn about endangered species," said Thomas Gillespie, a UCLA geography professor and the atlas's project lead. "The spotted owl, the bighorn sheep and blue whales — all here in L.A.! If you don't know to care about them, they'll probably just disappear."
The site, one of the nation's most comprehensive publicly available biodiversity atlases, enables users to explore how geography, climate and human impacts shape where key plant and animal species live, and how the county's habitats could change due to predicted changes in climate and land use by 2050.
Some of the maps in the atlas show the presence of roads, parking lots, hiking trails and other hard surfaces throughout the region. That information could be useful, for example, to show how those so-called impervious surfaces influence the location of nonnative plant species. That's important because some non-native species, such as fountain grass and black mustard, have been linked to an increased risk for wildfire.
Impervious surfaces also have been linked to the spread of certain animal species, including native coyotes, a link that could reflect the animals' increasing ability to adapt to urban areas.
"Because there are so many people in L.A., it may be easy to forget how close many common species and their habitats are to us," said Monica Dimson, a UCLA doctoral student in geography who developed the atlas with Gillespie. "People can't get excited about what they can't see, so we hope that presenting L.A. in this interactive, special way will be helpful."
Users can also look up whether any street address is located in a wildfire hazard area, and see the boundaries of every wildfire that has burned in the county since 1876. The atlas reveals a pattern of larger fires in Southern California in recent years overlapping areas where invasive fountain grass and mustard are likely to grow.
"Wildfires are part of living in L.A., and I think people should have a good, interactive understanding of where they occur," Gillespie said.
Other findings include:
- Many parts of Los Angeles County — Santa Monica and the City of Los Angeles in particular — have become greener since 2000. Dimson said this is most likely because of projects like Million Trees L.A. and other tree-planting efforts over the past two decades.
- Light pollution has decreased within the Santa Monica Mountain National Recreational Area and San Gabriel Mountains over the past 20 years. This reflects the success of efforts by the National Park Service and other federal and state agencies to reduce light pollution and ecological harm from other human activity in protected areas.
- Nonnative bird species such as the red-crowned parrot are most likely to be seen in the Pasadena area. Ironically, the red-crowned parrot is considered to be endangered in its native habitat of eastern Mexico (where there are fewer than 2,000), but they are numerous in Southern California.
- Average temperatures in Los Angeles County are predicted to increase by at least 1.9 degrees Celsius (3.4 degrees Fahrenheit) by 2050. In some areas farther inland, average temperatures could even increase by an average of 3.9 degrees Celsius (about 7 degrees Fahrenheit).
Work on the Biodiversity Atlas L.A. began in 2016 after the project received funding from the UCLA Sustainable LA Grand Challenge, a university-wide initiative aimed at applying UCLA expertise and research to transform Los Angeles into the most sustainable megacity by 2050. The atlas's next update, to be completed later this year, will include diversity patterns and identify priorities for conservation and restoration, Gillespie said.
