Did you know that California is a biodiversity hotspot? In honor of California Biodiversity Day (Sept. 7), let’s explore what makes our region so unique and what we can do to protect it.
The California Floristic Province encompasses much of the state of California and contains a wide variety of ecosystems, from coastal sage scrub to redwood forests and salt marshes. The vascular plant species found here outnumber those found in the entire central and northeastern United States, and more than 60% of them are found nowhere else in the world. More bird species breed here than anywhere else in the U.S., and nearly half of the amphibians found here are found nowhere else in the world.
And yet California is also one of the four most ecologically degraded states in the U.S. Part of what makes an area a biodiversity hotspot is that it is not only biodiverse but also threatened by habitat loss. In California, the biggest threat to habitat is increased development that sprawls into our open space. Increased competition by invasive species is also a factor, and of course, the wildfires fueled by climate change can wipe out thousands of acres of habitat in a very short time.
Why is biodiversity important?
At its core, biodiversity is the measure of the health of the planet. Each separate ecosystem relies on complex, interconnected communities of living organisms, each of which plays its own role. When species are lost, the entire ecosystem suffers, with cascading effects. For example, the loss of predators can lead to an explosion in prey populations, which in turn can wipe out plant communities. With loss of biodiversity, ecosystems become more fragile and less able to adapt to impacts from climate change, disease, and human activity.
When we convert biodiverse landscapes to monocultures – as happens when natural areas like rainforests are replaced with agricultural plantations – we see the extreme version of this scenario. A single disease or pathogen can wipe out an entire agricultural area if it’s been planted with a single crop.
Thousands of critical medicines, including penicillin, morphine, and most of the antibiotics we take today, were derived from natural sources, and we’re still making new discoveries about potentially life-saving drugs found in nature. In 2021, scientists isolated a molecule from the leaves of the European chestnut tree that has the power to neutralize dangerous, drug-resistant staph bacteria such as methicillin-resistant Staphylococcus aureus (MRSA). And marine bacteria from the deep ocean floor have resulted in a drug that could treat aggressive brain cancer.
That’s why it’s such a serious issue that we’re in a biodiversity crisis. Animal populations have plunged by an average of 69% since 1970, and up to 1 million species are currently threatened with extinction. Many scientists believe we are currently living through the sixth mass extinction of life on earth, comparable to the extinction event that eliminated the dinosaurs – but this one is caused by people.
What we can do
As devastating as these statistics are, we can still take action to counteract this loss of biodiversity. In 2020, the state of California announced the 30 x 30 initiative, whereby the state committed to conserving 30% of the state’s lands and coastal waters by 2030. Protecting biodiversity is one of the central goals of this initiative.
In addition, we can all take steps to increase biodiversity in our own backyards. Planting a native plant garden will provide food and habitat for birds and insects, and not planting (and actively removing) invasive species like English ivy will help our native biodiversity survive. You can learn about the power of urban gardening at a free online event hosted by Acterra on Sept. 26 at 4:30 (register here).
To combat habitat loss, we can support plans to focus future growth in cities rather than on open space – also known as “build up, not out.” When we build new homes in the wildland-urban interface (WUI), we’re not only invading habitat areas that are needed by wildlife, but we’re putting people at risk from wildfires, floods, and other natural disasters.
Finally, we can raise awareness of the importance of biodiversity. September 7 is California Biodiversity Day, and there are over 100 in-person and virtual events celebrating biodiversity. You can get involved with nature-mapping, either on your own by identifying species on iNaturalist, or by participating in a bioblitz with the help of nature experts.