This US island is home to flora found nowhere else. Now, a wildfire threatens extinction

In the southeastern corner of Santa Rosa Island, a grove of several thousand Torrey pine trees, some exceeding 250 years in age, exists. The only other location in the world where these distinctive pines can be found is in San Diego County; however, biologists classify the populations in these two regions as different subspecies. Thus, when an uncommon wildfire erupted on Santa Rosa Island late last week, firefighters acted swiftly to prevent it from encroaching upon this grove, which is vital for the survival of the island's Torrey pines.

Thus far, their efforts appear to be effective—despite the fact that nearly one-third of the island has been engulfed by the 18,000-acre blaze. Nevertheless, biologists who are familiar with the unique ecosystem of Santa Rosa Island continue to monitor the situation with growing concern, as the fire threatens six endemic plant species that are not found anywhere else on Earth.

"We're all watching this with a little bit of trepidation," stated Dr. Heather Schneider, director of research and conservation at the Santa Barbara Botanic Garden. "Are these plants going to recover on their own?"

Conservationists widely regard Channel Islands National Park as a remarkable success story, where rare native plants have experienced a significant resurgence in recent decades after enduring over a century of damage from non-native livestock and introduced game animals. Presently, the Channel Islands harbor numerous endemic plants—species that exist solely in that region. Notably, six of these unique species, including the Torrey pines, are found only on Santa Rosa Island. According to Schneider, approximately ten percent of the island's plant species are classified as rare.

The ongoing fire on Santa Rosa Island poses a potential setback to this recovery. Historically, wildfires have infrequently occurred on the Channel Islands, raising concerns among conservationists regarding whether the island’s rare species possess the necessary evolutionary adaptations to survive such intense fires.

The threat to species found nowhere else

The Torrey pine grove has garnered significant attention; however, the fire endangers all six endemic plant species present on the island.

Steve Junak, a biologist who has dedicated nearly four decades to studying the flora of the Channel Islands, remains cautiously optimistic about the prospects for some of these plants. The Santa Rosa Island manzanita, for instance, belongs to a plant genus known to thrive in the aftermath of fires, while the Santa Rosa Island live-forever flourishes in open areas characterized by sparse vegetation. Furthermore, the Hoffman's slender-flowered gilia is typically found in sandy environments, which present less fuel for wildfires.

However, Junak expresses concern regarding the fate of the Torrey pine grove and the East Point dwarf dudleya, a succulent species whose habitat has already been affected by the fire.

"Their response to fire is not known at all," Junak commented regarding the dudleya. "They're only found in a very limited area on the east end of Santa Rosa Island, where this fire is most concentrated. I hope they survive this event."

The impact of the fire on the soft-leaved Indian paintbrush, a yellow-flowering herb, also remains uncertain. Fortunately, the federally endangered plant's range extends to the northern parts of the island, which have yet to be impacted by the flames.

A rare island fire

Historically, wildfires on the Channel Islands were ignited only by infrequent lightning strikes. The current fire raging on Santa Rosa Island, however, is believed to be human-caused.

According to the US Coast Guard, a 67-year-old sailor crashed his boat into the rocky shore of the island last week. In an attempt to signal for assistance, he fired at least two flares, leading to speculation that these flares may have initially ignited the blaze. The Coast Guard successfully rescued the sailor, who appeared to have sustained no injuries.

Additionally, SFGate has released footage showing a burning sailboat on the shoreline of Santa Rosa Island, likely related to the incident involving the stranded sailor. The cause of the boat's fire—whether from an explosion or the sailor's actions—remains unclear.

Authorities are aware of the multimedia evidence related to the incident, and the fire remains under investigation, reported Sierra Frisbie, a fire information officer assigned to the Santa Rosa Island incident.

A helping hand

Recent drone footage suggests that firefighters have thus far succeeded in protecting the Torrey pine grove from significant damage.

"Initial video from the area offers cautious optimism because some green canopy remains visible," Frisbie noted. "However, scientists emphasize that it is still too early to determine the long-term survival of many trees. Delayed mortality can occur months or even years later, particularly in species that are not well adapted to wildfires."

Biologists will need to wait for the fire to be brought under control to fully assess the extent of the damage to the island's rare flora. Junak warns that the implications of this damage may take time to comprehend.

"When we consider the effects of this fire on the island's special plants, we must also think about how the endemic insects and animals that interact with these plants are being affected," Junak elaborated in an email. "The island's plants provide vital nectar, pollen, food, and shelter for these creatures."

"Another adverse impact of this fire will be the destruction of the soil crusts surrounding some of these plants," Junak continued. "These crusts—composed of lichens, algae, mosses, and liverworts—are crucial for inhibiting the spread of invasive non-native species and reducing soil erosion, especially during periods of heavy rainfall."

Should the fire result in catastrophic effects on Santa Rosa Island's rare plants, the Santa Barbara Botanic Garden may be positioned to assist in recovery efforts. The institution has spent decades developing a seed bank that biologists can utilize to help restore any lost plant species, including a conservation grove housing 40 Torrey pines.

"This is why we do what we do," Schneider remarked. "There's always the hope that nature will recover on its own. But if it doesn't, we have been gathering the seeds we need to help."