(or the deer icon below) to report dead wildlife and help us understand the impact of the December 2017 fires!
The Thomas Fire
has been burning for 12 days now ultimately burned for 40 days, having moved primarily northwest into the Los Padres National Forest and westward into the front ranges of Santa Barbara County. While the threats from this fire are far from over, this f ourth third second largest (see the table at the end of my post) fire in California history has charred a huge amount of landscapes across our Ventura County home. Thomas and the rest of the fires across California this year and may well be a harbinger of the coming years. So understanding what this conflagration has done and will do to our ecosystems will be key for responsible planning and management.
The list of short- and long-term environmental impacts from this massive event is growing. My ESRM Program colleagues and I are documenting several of these, many of which are out of sight, out of mind for the general public. But thanks to the viral bunny man video from last week, one type of impact has jumped to the fore of pubic awareness; wildlife deaths.
A fragmented landscape
Our Pirate Lab, aided by hundreds of students from our ESRM Program’s Conservation Biology classes, has been documenting road kill along the varied networks of roads across Santa Barbara, Ventura, and Los Angeles Counties. This study was designed to both help us understand the impacts of ecological fragmentation and the relative abundance of vertebrates across our region. As such, we have an excellent handle of the baseline or “background” mortality rates of animals across the south coast. In the wake of our recent fires, the question now becomes how have the flames of 2017 impacted our wildlife populations across Ventura County and the wider region.
Lessons from 2013’s Camarillo Springs Fire
Our lab’s first detailed exploration of the impact of fire upon our local wildlife began in May 2013. The Camarillo Springs Fire burned 9,809 hectares (24,238 acres) in the western Santa Monica Mountains over a five day period. While few university buildings burned, the entirety of our California State University Channel Islands main campus property burned on the morning of May 2, including all of our long-term monitoring sites proximate to Calleguas Creek. Fortuitous road kill monitoring, camera trapping, owl pellet, and insect sampling immediately prior to the burn and subsequent post-fire monitoring provided us with a somewhat unique opportunity to study the effects of this fire on animal abundance and diversity.
Larger vertebrates (e.g. bobcats, coyote, deer) generally survived the flames by running into Calleguas Creek or the surrounding unburned farmland. In contrast, smaller vertebrates (e.g. lagomorphs, rodents) were killed in large numbers by the fire and much less abundant in the days and weeks post-burn. In the months immediately following the fire, all vertebrate encounters declined to rates well below both initial post-fire and previous year levels. Insects showed a much more diverse fire response; invertebrate biomass was initially unchanged by the fire, however diversity dropped in the wake of the burn (with flies and non-native Argentine ants coming to dominate our post-burn insect community). Post-fire generalist invertebrates appear to be more successful relative to more specialist functional groups.
A team of my ESRM undergraduates (Kristin Lane and Morley Hense who focused on Barn Owls, Tyto alba impacts; Megan Hines and Lindsey Sones who focused on White-tailed Kites, Elanus leucurus impacts) studied fire effects upon birds of prey, ultimately confirming with independent evidence that the smallest critters were the most heavily hit. Owls living on our CSUCI campus found only half the types of prey they did to before the fire. And when those owls caught a mouse post-fire, those squeekers were much larger on average than a typical mouse caught by those same owls at any point over the previous three years.
Our invertebrate community was impacted more complexly than the vertebrates. The amount of flying insects at CI was initially little impacted by the fire, but by the first anniversary they had become markedly rarer. In contrast, ground-dwelling insects showed an immediate response to the conflagration. Spiders, beetles, and other crawling insects exploded right after the fire and have been growing more numerous ever since (thanks to work of another of my students, Kurt Zias). Kurt found the addition of “bug” biomass was primarily being driven by more generalist invertebrates, with more specialist insects having fared poorly or disappeared entirely in the wake of the fire that decimated >95% of the plant biomass (many of these plant species are needed by insect specialists to survive).
That intense, early season Springs Fire in 2013 coupled with extremely low rainfall over the ensuing years combined to dramatically reduce the number of animals across all our study sites in the western Santa Monica Mountains with associated long-term consequences for ecosystem functioning of these coastal areas.
Springs Fire boosted road kill, will the Thomas Fire?
In the immediate wake of the 2013 Springs Fire, we saw a huge spike in deaths along roadways around the burned region. While every category of road kill was up, we soon saw a drop off of small-boded critters, suggesting that their abundance in the landscape declined markedly post-fire.
We now want to confirm this finding as a general pattern of such wildfires by exploring road kill (and animal deaths generally) in the wake of the Thomas and other local fires…and you can help us!
If you happen see any dead animals along the roadsides or while hiking in open spaces over the next few months, please report it via our online reporting tool. All you need is an internet connection.
Thanks in advance for any help you can send our way. As we look towards a future with more wildfires and extended drought periods, insights from the research of our Pirate Lab, ESRM faculty and students, and colleagues across our region may well prove a critical piece of the puzzle for managers seeking to conserve our natural heritage in a warmer, more fire-prone California.
Largest CA Wildfires
|fire||county||acres||km2||start date||structures||human deaths|
|Thomas||Ventura & SB||281,893||1,141||December 4, 2017||1,343||2|
|Cedar||San Diego||273,246||1,106||October 1, 2003||2,820||15|
|Rush||Lassen||271,911*||1,100*||August 1, 2012||2,820||15|
|Rim||Tuolumne||257,314||1,041||August 1, 2013||112||0|
|Zaca||Santa Barbara||240,207||972||July 1, 2007||1||0|
|Matilija||Ventura||220,000||890||September 1, 1932||0||0|
|Witch||San Diego||197,990||801||October 1, 2007||1,650||2|
|Klamath Theater Complex||Siskiyou||192,038||777||June 1, 2008||0||2|
|Marble Cone||Monterey||177,866||720||July 1, 1977||0||0|
|Laguna||San Diego||175,425||710||September 1, 1970||382||8|
|Basin Complex||Monterey||162,818||659||June 1, 2008||58||0|
|Day||Ventura||162,702||658||September 1, 2006||11||0|
|Station||Los Angeles||160,557||650||August 1, 2009||209||2|
|Rough||Fresno||151,623||614||July 1, 2015||4||0|
|McNally||Tulare||150,696||610||July 1, 2002||17||0|
|Stanislaus Complex||Tuolumne||145,980||591||August 1, 1987||28||1|
|Big Bar Complex||Trinity||140,948||570||August 1, 1999||0||0|
|Happy Camp Complex||Siskiyou||132,833||538||August 1, 2014||6||0|
|Soberanes||Monterey||132,127||535||July 1, 2016||68||1|
|Campbell Complex||Tehama||125,892||510||August 1, 1990||27||0|
Notes: Rush fire burned 271,911 in California and 43,666 acres in Nevada for a total in both states of 315,577 ac. These data emphasize fires from 1932 onward, the inception of the state's official record keeping (what you can call the "modern era"). While we typically pin the modern era with the establishment of statehood in California and so prefer 1850 onward for most of our historic discussions, getting precise historic fire extent ex post facto is a challenge (see Goforth & Minnich 2007). What was likely an amalgamation of several smaller fires, the 1889 Santiago Canyon Fire is popularly reported as 308,000 acres (1,250 km2, e.g. Keeley & Zedler 2009) but possibly a complex of smaller fires one or two orders of magnitude smaller (Goforth & Minnich 2007).
Note: CalFire’s published, post-1931 fire sizes are sourced from this document.
Our friends from the Santa Barbara Wildlife Care Network asked us to include the reporting numbers for wildlife you might come upon: