Hidden cameras spot wildlife returning home after 2018 megafire

Newswise — Berkeley —In the summer of 2018, the Mendocino Complex Fire wreaked havoc on UC's Hopland Research and Extension Center (HREC), turning its picturesque Northern California grassy hills and oak-studded landscapes into a desolate expanse of smoldering ashes.

"It felt like something straight out of the Lord of the Rings - akin to Mordor. It was difficult to envision anything surviving," expressed Justin Brashares, a professor of environmental science, policy, and management at the University of California, Berkeley.

However, a few months after the devastating fire, a glimmer of hope emerged as animals like coyotes, gray foxes, and black-tailed jackrabbits were spotted returning to the area. These observations were made through a grid of motion-sensor camera traps that Brashares' lab had been operating at HREC since 2016. The Hopland Research and Extension Center is a multidisciplinary research and education facility situated along the banks of the Russian River, approximately 13 miles south of Ukiah.

Kendall Calhoun, a graduate student at UC Berkeley and a member of Brashares' lab, was astonished by the findings. She served as the lead author of a new study that examined over 500,000 camera grid images taken at HREC before and after the Mendocino Complex Fire. The study aimed to gain insights into how the wildfire affected the population of small- and medium-sized mammals on the property.

Published in the journal Ecosphere on a Monday, the study stands out as one of the pioneering works to conduct a comparative analysis of continuous wildlife observations before and after a megafire. Moreover, it represents one of the few studies that delve into the effects of megafires on California's oak woodlands. Despite their significant presence in the state, oak woodland ecosystems have not received as much attention in wildfire research as the conifer forests of the Sierra Nevada.

According to Justin Brashares, who leads the research, these oak woodlands and grassland savannahs are emblematic of California's distinctive biome or ecosystem. They play a vital role in supporting livestock grazing and serve as the primary habitat for growing wine grapes. Managing these ecosystems effectively is of paramount importance.

The study focused on eight animal species, revealing that six of them displayed remarkable resilience, utilizing the area similarly and with similar frequency as they did before the fire. These species included coyotes, black-tailed jackrabbits, gray foxes, raccoons, striped skunks, and bobcats. However, it was observed that the Western gray squirrel and black-tailed deer seemed to be more susceptible to the impacts of the fire.

Brashares and Calhoun have deduced that many species were able to persist in the area due to small pockets of tree cover that remained untouched by the fire. Camera trap photos captured numerous animals seeking refuge in these unburnt patches, utilizing them as sources of food and resources while the more heavily scorched areas slowly recovered. Surprisingly, some animals were observed frequenting these locations even more after the fire than they did before.

These discoveries underscore the significance of employing techniques such as grazing and prescribed burning to mitigate the intensity of wildfires when they occur. Lower severity fires are more likely to preserve the tree canopy and create the diverse forest conditions that benefit ecosystems adapted to fire.

"Despite the immense heat and devastation caused by the fire, it managed to spare these small, unburnt areas. We were astonished by how rapidly many species moved into these habitat patches and then extended their presence back into the burned areas as they recovered," Brashares expressed. "This finding holds valuable insights for forest management because we can implement measures on the landscape that enhance the likelihood of leaving behind such fragments when wildfires do happen."

An approaching inferno

While visiting New Zealand, Calhoun received a text message from study co-author Kaitlyn Gaynor with alarming news: the HREC was engulfed in flames.

"My immediate response was, 'Is everyone safe?'" Calhoun recounted.

For the past two years, Calhoun had been actively involved in maintaining 36 camera traps strategically placed across the property. These cameras were part of a collaborative effort with the California Department of Fish and Wildlife, aiming to test a novel method of monitoring wildlife populations throughout the state.

Initially, Calhoun had joined Brashares' lab with the intent of studying the effects of megafires on wildlife diversity. However, due to the unpredictability of wildfire occurrences, finding a suitable study site had proven challenging. The Mendocino Complex Fire, though terrifying and devastating, unexpectedly presented a rare opportunity.

According to Calhoun, reports indicated that the situation was indeed harrowing as the fire approached the property, with people living on-site requiring urgent evacuation. The fire ultimately consumed more than half of the area.

Despite being continents away, Calhoun was eager to take immediate action upon returning to the site, ensuring that all the necessary data would be collected without delay.

About two months after the fire had ravaged the HREC, Calhoun and the team returned to a scene resembling a desolate "moonscape" with still-smoldering trees. Their primary mission was to assess the status of the camera traps, only to find that 13 of them had been partially melted by the intense blaze. They diligently replaced the damaged camera parts and took great care to set up the traps in the same positions and orientations as before the fire, ensuring the consistency of their data as much as possible.

Every three months, the team revisits all 36 cameras on the site, meticulously downloading the captured photos, checking for operational efficiency, and clearing any obstructing grass or debris from the view. Hours upon hours are spent meticulously reviewing each shot to discern and identify the animals captured in the images, logging the valuable data.

"It's surprising how much of the collected data consists of grass swaying in the wind," Calhoun noted.

The camera traps not only capture small- and medium-sized mammals but also larger animals like black bears and mountain lions. However, since these apex predators boast extensive home ranges, often far surpassing the HREC's 5,300 acres, the study area cannot provide accurate insights into their distribution.

According to Calhoun, there was a noticeable decrease in the sightings of these animals after the fire, indicating that they took longer to return to the area following the blaze.

Upon completing his Ph.D. this summer, Calhoun has ambitious plans to continue his research as a 2023 Smith Fellow, investigating the effects of significant changes in fire patterns on wildlife species throughout California. As part of this endeavor, he aims to gather more extensive data on apex predators to gain a deeper understanding of how these animals are affected when large fires disrupt their expansive home ranges.

Additional study co-authors include Benjamin R. Goldstein, Kaitlyn Gaynor, Alex McInturff and Leonel Solorio of UC Berkeley. This work was supported in part by the California Department of Fish and Wildlife (CDFW Grant # P1680002) and by the NSF Graduate Research Fellowship program.