Majestic Joshua trees facing extinction as a result of climate change
As a species, Joshua trees have survived for 2.5 million years in the middle of the Mojave Desert, standing tall and drawing tourists from across the world to see these ancient wonders.
But now it appears that climate change may destroy what time couldn’t, according to Live Science:
“In a new study published June 3 in the journal Ecosphere, researchers and volunteer scientists surveyed nearly 4,000 trees in southern California’s Joshua Tree National Park to figure out where the oldest trees tended to thrive during historic periods of extreme heat and drought. (A single Joshua tree can live up to 300 years.) Then, the researchers estimated how much of these Joshua safe zones (or ‘refugia’) would survive to the end of the century based on a range of climate change predictions.
“The study authors found that, if greenhouse gas emissions are seriously curbed and summer temperatures are limited to an increase of 5.4 degrees Fahrenheit (3 degrees Celsius), about 19% of the park’s Joshua tree habitat would survive after the year 2070.”
But if no action is taken on climate change (which seems highly unlikely in the United States under the current administration) and temperatures continue to rise, only 0.02% of the tree’s habitat will live to see the end of the 21st century.
Lynn Sweet, a plant ecologist at the University of California, Riverside, notes that humans have to make a choice, and it needs to be made now:
“The fate of these unusual, amazing trees is in all of our hands. Their numbers will decline, but how much depends on us.”
The trees in Joshua Tree National Park are iconic symbols of the Southwest, and they’ve survived longer than nearly any other plant species in the Mojave:
“Joshua Tree National Park covers 1,200 square miles (3,200 square kilometers) of sandy, hilly terrain in the desert between Los Angeles, Las Vegas and Arizona. The spiny-armed Joshua trees have survived millions of years of climate ups and downs by holding on to large amounts of water to carry them through the region’s harshest droughts.”
Now, however, young tree seedlings are unable to store enough water to survive prolonged dry spells as global temperatures continue to rise each year:
“During long droughts — such as the epic, 376-week-long one that lasted from December 2011 to March 2019 in California — various parts of the park became too parched to support young Joshua tree growth, preventing the species from reproducing properly.”
Sadly, even if climate change is dealt with, the danger of wildfires is also an existential threat to the Joshua trees:
“According to the researchers, fewer than 10% of Joshua trees survive when wildfires rush through their habitats — thanks, in part, to car exhaust coating desert shrubs with flammable nitrogen. This, at least, is a threat that can be addressed on a local level, right now.
“‘Fires are just as much a threat to the trees as climate change, and removing grasses is a way park rangers are helping to protect the area today,” Sweet said. ‘By protecting the trees, they’re protecting a host of other native insects and animals that depend on them as well.'”
One day, we may have nothing left of the Joshua trees but pictures and memories.
Featured Image Via Needpix