Can Joshua trees survive climate change?/Kurt Repanshek

With concerns that the Southwest's iconic Joshua trees will be pushed out of 90 percent of their current habitat by the century's end due to climate change, a group has petitioned the U.S. Fish and Wildlife Service to have the tree listed as "threatened" under the Endangered Species Act.

WildEarth Guardians filed the petition last week. According to the group, multiple climate models predict severe range contractions in the next century for this species. The trees will have difficulty moving to more hospitable habitat because they reproduce and disperse so slowly.

“Joshua trees are an irreplaceable part of the Southwest and we must protect them,” said Taylor Jones, endangered species advocate for WildEarth Guardians. “Because Joshua trees grow so slowly, they cannot quickly adjust to our changing climate and will need safeguards to ensure they are here for future generations.”

A USGS study completed in 2011 concluded that Joshua trees, a spindly member of the Yucca family that are equated with the hot, arid Mojave Desert, could be restricted to the northernmost portion of their current range as early as the end of this century. Additionally, the ability of Joshua trees to migrate via seed dispersal to more suitable climates might be severely limited, the research noted.

"The Southwest is a climate change 'hotspot' and is already feeling the effects, with higher temperatures, longer droughts, and larger and more frequent fires, according to WildEarth Guardians. "Taken together, these climate change impacts could spell disaster for Joshua trees."

The non-profit group says the trees need wet intervals to successfully reproduce and cold periods to thrive. 

“It’s already difficult to be a Joshua tree, since many factors need to come together in just the right way for them to reproduce,” said Jones. “We need to address climate change now if we want to see Joshua trees in the future.”

The petition triggers a 90-day deadline by which time the USFWSe must make an initial finding on whether the imperiled species warrants protections.