Jerimiah Oetting [outside]: Alright, so...what are we doing?
[about three people laugh as gravel crunches underfoot as they walk]
Taylor Ellis [outside]: Yeah, we're hiking into an area of the Woodward Fire.
JRO [in studio]: That's Taylor Ellis. He's a field biologist with Point Reyes National Seashore. We're hiking along the Bear Valley Trail, where the Woodward Fire burned last summer. I should mention that, as of mid-January , this area is closed to visitors. For good reason: crews are still working hard to make the roads and trails safe.
[gravel crunches underfoot]
TE [outside]: Uh, and, we want to see if we can get an owl detection today. Uh, we're kind of curious if the owl is still using its core area after the fire.
JRO [in studio]: This isn't the typical time to monitor spotted owls in the park. We were hiking in December. It's usually easier to spot the owls during their breeding season, between March and July.
TE [outside]: But we're still gonna go and check some of the known haunts they have and, uh, see if we can find them.
[Taylor mimics spotted owl hooting call out in the woods]
JRO [in studio]: Taylor is hooting for the owls to see if any reveal themselves to us. Six different spotted owl territories were impacted by the fire. Taylor says he hasn't visited all six yet to see how they were affected.
TE [outside]: The ones that I have seen, it looks like it didn't burn very hot in those areas, so most of the big older trees are there, which is important for spotted owls.
JRO [in studio]: This is prime spotted owl habitat, he says. An area with tall Douglas fir trees, some that are hundreds of years old.
Black fire scars stretch up the boles of some of the trees. But the burn was patchy. On one side of the trail, there were charred clumps of sword fern. But then, just uphill, bright green ferns appeared to be completely untouched. This area seemed a good example of a fire that might actually help spotted owls.
TE [outside]: It's not that any fire is good, but, sort of, a low-level fire that doesn't get too hot, which is what they would mostly be if they happened more often.
JRO [in studio]: In the last episode, we talked about how some plants in the park actually depend on fire. But what about wildlife? Plants aren't the only things impacted by fire, and that means the critters that call Point Reyes home are also adapted to recover.
There are a ton of animals here. Almost half of North America's bird species have been spotted in the park. There are mammals, fish, amphibians, reptiles, and thousands of invertebrates. Over 50 of these species are considered rare, threatened, or endangered.
With all the other forces that threaten their existence, how do these animals continue to persist after a fire?
On the podcast today: how wildlife coexists with wildfires. Spotted owls, red-legged frogs, steelhead trout—they're just a few examples of animals you may have heard of that could be impacted by fire. But there's another animal—one you might not even know about, that's unique to Point Reyes. A living fossil—elusive, hidden and all around peculiar. It could be lurking just feet away from a trail and you'd never know.
All this and more, stay tuned….
JRO [in studio]: This is the Natural Laboratory, from Point Reyes National Seashore. I'm Jerimiah Oetting.
[gravel crunches underfoot]
TE [outside]: We just have a really high density of spotted owls in Marin County, um, compared to other parts of their range.
JRO [in studio]: Marin County is one of the last refuges for the northern spotted owl. Populations of the owl have dwindled across their range, which extends from just south of Point Reyes National Seashore all the way up towards British Columbia. The northern variety is one of three spotted owl subspecies. It prefers big old growth forests that have vanished over the last couple of centuries. A robust spotted owl population is a good sign of a healthy forest. Unfortunately, though, the owls are listed as threatened, at both the federal and state levels. What little habitat remains for northern spotted owls has been encroached upon by both humans, and by a close but unfriendly relative—its boisterous cousin, the barred owl.
Barred owls are invasive out West. They aggressively take over spotted owl habitat. Research shows that spotted owls require about four times the territory of barred owls. That means that barred owls can pack more densely into areas that would have once belonged to only a few spotted owls.
This is partially because barred owls eat almost anything. They gobble up many of the foods that spotted owls depend on—like woodrats, deer mice, voles, and flying squirrels—but also amphibians, fish, even other birds. They're bigger and burlier than spotted owls. And they're more aggressive. For spotted owls, that means less resources and less space. They get pushed to the edges of their habitat where they struggle to survive.
TE [outside]: And that's what's happened a lot in places like Olympic National Park and Redwood National Park, both north of us.
JRO [in studio]: But not in Marin County. The first barred owls appeared in Marin in 2002. Since then, they've had a steady presence in the area. But luckily for the spotted owl, they haven't completely taken over as they have elsewhere. Northern spotted owls in Marin County are doing better than pretty much everywhere else in their range.
TE [outside]: You know, I think that might be because there's a lot of food available to them in the form of all the wood rats that we have out here. We'll probably see some of their nests, at least in unburned areas of the forest.
JRO [in studio]: Those woodrat nests can burn up in a fire, removing a vital food source for spotted owls. But fire can also be good for the owls, clearing out shrubs and opening up the forest understory. A more open forest floor makes it easier for the owls to hunt.
TE [outside]: And then they also, of course, want some decent, kind of like, canopy cover, like a kind of closed canopy that they can sort of hide out in, you know, they can perch there, you know, hawks and stuff can't see them from above. And they can just kind of quietly sit there in the shade, um, and just wait for some prey to come along.
JRO [in studio]: For spotted owls, an open understory and a nice overstory is a great balance—one enabled by fire. But spotted owls are predators. And they can fly. For their rodent prey, escaping a fire is a bit of a challenge. And rodents are an important food source, not just for owls, but for animals like bobcats, foxes, and coyotes.
TE [outside]: You might lose some wood rats in the actual fire event, but, you know, they are rodents. They will be back from surrounding areas.
JRO [in studio]: Other terrestrial animals are sensitive to fire, too. California red-legged frogs live in the park. Like the spotted owl, red-legged frogs are federally protected, because they're a threatened species.
Dr. Patrick Kleeman is a research biologist with the USGS in Point Reyes. Most of his work focuses on conserving endangered amphibians.
PK [in studio]: Luckily, our amphibians, locally, don't seem be greatly impacted by wildfire. Of course, any amphibians that are in a terrestrial situation away from a pond are probably going to get burned up. So, it's definitely going to affect individuals, but doesn't seem to greatly affect the actual populations.
JRO [in studio]: Dr. Kleeman says after the Vision Fire 25 years ago, scientists surveyed the breeding ponds known to be important for amphibians.
PK [in studio]: After the Vision Fire, they typically found the same amphibian assemblage at those ponds. And that's great news. And so, other things, like mountain beavers, is definitely a direct effect that can have consequential damage for years to come.
JRO [in studio]: Mountain beavers. Ever heard of them? Despite their name, they aren't a mountain variety of the bucktoothed tree chompers that you're probably thinking of. Nope. These are far stranger.
Seth Bunnell [outside]: Mountain beavers are coprophages. And they're, um, hosts to the world's largest flea. And they're also the only member, the only living species in an extinct family that was once widespread, and they're one of the most primitive rodents.
JRO [outside]: Cool. So, they eat their own poop. They have the largest...or they eat not their own poop, but like…
SB [outside]: Yeah, they eat their own poop.
JRO [outside]: Okay.
SB [outside]: They're very hungry because they live on salad. And they have to eat a lot. And to get the nutrients out...like a rabbit does the same thing. They sort…so they have two generations of droppings, and the first generation of droppings, they eat 'em again to get more nutrition.
JRO [in studio]: That's Seth Bunnell. He's a field biology extraordinaire. He knows a thing or two about mountain beavers. If you didn't catch it, not only do mountain beavers eat their own poop, but they're plagued by the world's largest flea, commonly known as the mountain beaver flea. The flea can be up to half an inch long.
Seth also mentioned that mountain beavers are the only living species in their genus, Aplodontia, and in their family. They're a living fossil—a relict [sic] of a group of animals that were once widespread eons ago.
But they're not just unique because of their strange behaviors and life histories. They look pretty weird, too.
SB [outside]: They have very small eyes, but I assume they can see some. They have very...a lot of whiskers. And they probably have a very good sense of smell. And, um, a lot of…they're very tactile. If you look at their whiskers, that's like a big ol' fan of whiskers. They can probably feel every side of their burrow and they can probably feel every plant around them, and they can probably feel, like, you would think, vibration really well.
And they have pretty well-developed looking ears although they're not as big like mouse ears but they're...they're funny ears. I mean, they've got strange ears.
They've got an unusual, kind of, shaped body and feet and ears...and eyes.
Unidentified voice [outside]: Yeah, they're a weird lookin' animal.
JRO [in studio]: Mountain Beavers are about two to three pounds and roughly a foot in length. They have a large skull compared to their body size. The few photos people have managed to capture of them, they look almost awkward, like they don't quite fit in. They're considered the most primitive living rodents, furry with long whiskers and black, beady eyes.
Further north, in the temperate rain forests of Oregon and Washington, mountain beavers are so common they're sometimes considered a backyard pest. But we have our own endemic subspecies here—the Point Reyes mountain beaver. It's unique to this area.
Point Reyes mountain beavers live at the southern edge of the mountain beaver's coastal range. The California Department of Fish and Wildlife lists it as a species of special concern, potentially vulnerable to extinction.
Scientists know little about the Point Reyes mountain beaver. But they do know its population is pretty small. And that the animals are highly vulnerable to fire.
Patrick Kleeman [in studio]: They can be severely impacted by fire because they really require, you know, a moist understory of vegetation.
JRO [in studio]: That's Dr. Patrick Kleeman, again, the research biologist at USGS in Point Reyes.
PK [in studio]: And they have these primitive kidneys, they can't concentrate urine. So, they're urinating all the time. So, they have to replace like a third of their body weight in water every day. And that typically comes from, you know, harvesting vegetation around them. If that gets burned away, there's just literally no way for them to survive.
JRO [in studio]: He says that mountain beavers don't move around much. If a fire comes or their habitat is burned away, they don't have much hope of survival.
PK [in studio]: But what was shown was they can also come back as the vegetation does get restored over time, but it takes time.
JRO [in studio]: A lot of what we know about the Point Reyes mountain beaver comes from work done by Dr. Gary Fellers, a park service biologist who retired in 2013. Unfortunately, Dr. Fellers recently passed away in 2019. Dr. Kleeman remembers Dr. Fellers as a force in field biology, pioneering research methods for studying wildlife. The two were close.
PK [in studio]: We, you know, just worked together and knew each other for a long time. He was a really excellent biologist, he was kind of an old-school biologist, he had very broad interests. And he's very, you know, observational and natural history oriented, but he also produced really good science.
JRO [in studio]: The 1995 Vision Fire cleared away big swaths of the shrubs mountain beavers love in the forest understory: poison oak, sword fern, coyote brush, and coffee berry. Dr. Fellers saw this as an opportunity to locate their burrows and assess how fire may have impacted the species.
What he observed didn't look good for mountain beavers. With 40% of their habitat destroyed within the burned area of the Vision Fire, Dr. Fellers estimated that at most, less than 2% of mountain beavers survived. That's for a fire that only burned for nine days.
Dr. Fellers noted in his study that mountain beavers lived alongside fire for hundreds, even thousands of years. But at the time of the Vision Fire, there had been a century of fire suppression at Point Reyes. The Vision Fire was unnaturally intense and destructive.
PK [in studio]: You know frequent spotty fires are different than intense fires that take out huge swaths of land that we're seeing these days across California. So, you know, the patchy nature of what fires used to probably be like, prior to white settlement, is probably, you know, the reason they could persist.
JRO [in studio]: Dr. Fellers estimated it would take between 15 and 20 years for mountain beaver populations to recover. This year marked the 25th anniversary of the Vision Fire. But very little monitoring for mountain beavers has occurred in the park since the era of Gary Fellers.
PK [in studio]: Just like everything, you know, monitoring of any animal takes time and money. And, you know, nobody's been putting that out there.
JRO [in studio]: Money is one issue. But looking for mountain beavers is also just hard. Unlike hooting for spotted owls and waiting for them to swoop into view, mountain beavers are nervous, elusive creatures. Relying on seeing them to try and assess their population wouldn't really work out.
Instead, scientists use their burrows as an indicator of their population. With support from Point Reyes National Seashore Association, park service biologists plan to reboot a mountain beaver monitoring program. They invited Seth Bunnell, who we heard from earlier, to provide training for park staff.
SB [outside]: We wanted to just, kind of, all learn together and get a good search image for, uh, spotting the burrows and other evidence, you know, tracking them.
JRO [in studio]: I joined Seth and park staff in the field for a training session. Taylor Ellis was also there, who you heard hooting earlier in the episode. And Matt Lau, a park service ecologist who usually works with snowy plovers.
Seth is kind of a jack of all trades field biologist. He was carrying this impressive shepherd's staff; it looked kind of like a five-foot-tall walking cane.
SB [outside]: It's from a basque shepherd back in the early 1940's.
JRO [outside]: Oh cool. And you take it with you when you're out in the field, like, no matter what you're doing? Or just for mountain beavers or other burrowing things?
SB [outside]: No, I usually bring my titanium field hook that I bought from a snake wrangling company.
JRO [in studio]: Seth was showing us how to identify mountain beaver burrows. Their burrows are about the diameter of a large grapefruit. Seth was using the shepherd's staff to probe the burrows to see how deep they went, which kind of helped him determine whether or not it was actually a burrow or just a hole dug by some other animal.
SB [outside]: See this is more like chipmunk diameter, or maybe this looks like a mouse.
JRO [in studio]: We first explored some of the areas where Dr. Fellers had found mountain beavers decades ago. But there were a ton of shrubs.
JRO [outside]: Well one thing's for sure, they really like to always locate their burrows in a thicket of poison oak.
SB [outside]: Yeah, that's the worst part of this. [someone chuckles]
JRO [in studio]: Spotting a burrow in the patchy light underneath that shrub canopy seemed next to impossible. We later moved into the footprint of the Woodward Fire in an area off the side of a road, where the shrub layer had burned up in the fire.
SB [outside]: I think these are mountain beavers.
JRO [outside]: Like, this one right here?
SB [outside]: So, here, like, I can light it up for you if you want to come in.
JRO [in studio]: There it was...a burrow. Honestly, it was kind of anticlimactic. A hole in the ground among many holes in the ground.
SB [outside]: But look. It looks like stuff has been moved inside. See that? All that particulate? And then I would look at that and see if there's any clues in it, you know, like, if it's vegetable ma…plant material.
JRO [in studio]: But for an animal as elusive as the mountain beaver, a hole in the ground is about as close as you get. I was told that these burrows are not likely occupied any longer. After all, we were in a recently burned area. We'll hope the burrows former occupant got wise and fled before it was too late.
Taylor told me they found a burrow or two elsewhere they thought were occupied. With a motion-activated wildlife camera setup outside the burrow, he said they hope they can score a photo. In the meantime, all of us were inspecting holes in the ground, seeing how much of our fists fit in before the burrow tapered off. That's part of how you identify if it's actually a mountain beaver burrow.
You know, before I started making podcasts, I was a field biologist too. I've worked on quite a few monitoring projects. And in all of those projects, I've occasionally been struck by the realization that, to a casual observer, all of this looks absolutely ridiculous. Grown adults, crawling around on the forest floor, shoving our hands into rodent burrows. I mean, why are we doing this? Why do we care about a population of primitive rodents?
It's not easy to fully grasp how these animals fit into their ecosystems. But Dr. Kleeman has some ideas.
PK [in studio]: I think it's interesting that they're just such an ancient animal. I mean, they've been here forever. [chuckles] And they still persist. They are prey for things like bobcats and coyotes, mountain lions, definitely larger owls. They're probably really good nutrient cyclers because they do all this burrowing underground, they're aerating underground, they're taking all this plant matter underground. They're basically fertilizing underground. They're so much a part of that ecosystem out there—that coastal scrub ecosystem—it's just we don't think about them that much because they're not seen that much.
JRO [in studio]: We share this planet with some strange creatures. As I watched this group of professional biologists on their hands and knees, puzzling over the vacant burrows of rodents, I realized: we're pretty strange ourselves. Who are we to judge?
Humans have only been on this planet for about 250,000 years. The mountain beaver has been around for at least 50 million years. Now, the Point Reyes subspecies might be threatened with extinction. For all of its time in Point Reyes, the mountain beaver has kept humbly to itself. Doing what it does. Apparently eating its own poop, urinating constantly, and waging battle against gigantor fleas. Mountain beavers might not inspire the awe of a swooping spotted owl, but you can bet that they play an important role at Point Reyes. And that, I think, is worth studying. And worth protecting.
JRO [in studio]: Thanks for listening to this episode of the Point Reyes Natural Laboratory podcast. My name is Jerimiah Oetting and this is my last episode with Point Reyes. I really enjoyed making all of these and I hope you enjoyed listening to them. It was a great experience.
As usual, thanks to all the scientists who gave me their time and made this episode possible. And for the support of the Point Reyes National Seashore Association and the National Park Service. My name is Jerimiah Oetting and thanks for listening.
JERIMIAH OETTING: Before we get started, I should mention, once again, that we're recording this podcast in early January 2021. Parts of the park are still closed due to the Woodward fire. There's still a ton you can do at Point Reyes National Seashore. Just be sure to check the park's website and social media to plan your trip. Thanks, and happy hiking.
Hey everybody, this is Jerimiah Oetting with Point Reyes National Seashore. This is the second episode of our new podcast The Natural Laboratory. And we're talking, once again, about wildfire.
Last summer was a crazy fire season in California. There were whole days where it felt like the sun didn't come up at all, the skies just turned this weird apocalyptic orange color. People had to evacuate their homes and many of those homes were destroyed. Through all that chaos, it can be really hard to remember that fire isn't all bad. For the ecosystems in Point Reyes National Seashore—and throughout most of California—fire has its benefits.
In the last episode, we learned about the Woodward Fire, which burned in the park last summer. We also explored how its more destructive predecessor, the Vision Fire, impacted the park 25 years ago.
As Dr. Alison Forrestel, the former Fire Ecologist at Point Reyes, says: even hot destructive fires, like the Vision Fire, can have a silver lining…at least, ecologically.
ALISON FORRESTEL: I want to push back on the idea that the Vision Fire was bad and the Woodward Fire is good. The Vision Fire…it was bad from a human perspective, absolutely, and, frankly, the Woodward Fire was traumatic for the community, too. But just from a purely ecological standpoint, the Vision Fire was just as ecologically beneficial as the Woodward Fire.
JRO: For humans, wildfires are a threat. But for many otherspecies, those same fires can be a vital force. In this episode of The Natural Laboratory, we say goodbye to a historic summer of fire, and look forward to new growth: the plants that will rise out of the ashes of 2020. We'll explore what we can learn from the Indigenous people who managed to coexist with fire for thousands of years, even using it in beneficial ways. And we take a look at what visitors to Point Reyes National Seashore can expect to see over the coming months and years: wildflowers, new growth, a recovering landscape. We all hope for better days ahead in 2021. And at Point Reyes, it's going to be a sight to see.
JRO: You're listening to The Natural Laboratory from Point Reyes National Seashore.
JRO: I'm Jerimiah Oetting.
AF: Fire ecology is super complicated,
JRO: Dr. Forrestel is now the Chief of Natural Resources at Golden Gate National Recreation Area. But she was the Fire Ecologist at Point Reyes for nearly a decade.
AF: Almost all of the vegetation in California is evolved to fire in some way. And, you know, in some places, it's species that can tolerate some degree of fire, and in other cases, the plant species actually depend on fire to, you know, persist. And even in Point Reyes that range exists.
JRO: After millenia of fires sweeping through the landscape, plants have adapted to it. They return quickly after a burn.
AF: Many many many species have the ability to resprout post-fire, so coast live oak and bay trees and coyote brush and, you know, probably most of the shrub species.
JRO: On the opposite end of the spectrum are Douglas fir trees, which aren't very tolerant of fire. The Woodward Fire burned primarily in Douglas fir forest.
AF: Those trees are pretty sensitive to fire and it doesn't take that much heat to penetrate the bark and kill the cambium layer and thereby kill the trees.
JRO: Dr. Forrestel says bishop pine are on the extreme end of being fire dependent. Their cones only open with the heat of a flame. And other species, like blueblossom ceanothus and some manzanita species, have a seed bank that's buried in soil. Those seeds require fire or smoke to sprout.
AF: So, those are, you know, the species that really truly cannot persist without fire. If fire is absent from the landscape for too long, eventually, they would blink out. And too long is a very long time, you know, more than a century probably.
And the flip side of it is then if fire were on the landscape too frequently, they wouldn't have time to build up the seed bank for the next generation. I think there's a risk of too frequent fire for those types of species.
JRO: These fire-loving species thrive after a burn. Dr. Forrestel published a study in 2011, showing that ceanothus and bishop pine exploded back onto the landscape after the Vision Fire. The species expanded onto habitat that was once coastal scrub. The extent of bishop pine nearly doubled. Before the Vision Fire, bishop pine forests were only found on ridge tops. After Vision, the bishop pine forest community extended down those ridges all the way to the coast
At some point, after reading so much about the fire that started on Mount Vision in the park, and pouring through all of the studies about the fire's impact on the park's natural resources, I decided I should head up there and take a look at it myself.
[gravel crunching underfoot]
JRO [outdoors]: This is it. The infamous Mount Vision.
JRO: There's a narrow, unmarked trail that leads from a small parking area near the summit of Mount Vision. Actually, it's really more of a hill. It's an easy walk, but I did explore some shrubby offshoot trails here and there.
[gravel crunching underfoot]
JRO [outdoors]: Yaaaaghhh!
JRO: There were a ton of crowded bishop pines up there. That's not surprising. Like Dr. Forrestel said, these trees depend on fire. When bishop pine forests burn, they burn completely. Then, they grow back into a crowded forest. Over time, the forest will self-thin as weaker trees die and those with better genetics—or the seeds that just happened to sprout in a better spot—grow to be more mature.
But what struck me wasn't just that it was so dense—it's that bishop pine just looks like a tree that would burn. The trees on Mount Vision looked especially rough. Most of the living trees were scraggly, but there were also a lot of standing dead trees. These trees weren't burned in the recent Woodward Fire, so I wondered if there was something else going on.
AF: The conditions you see on the landscape now are the result of two factors. One is that the bishop regenerated with extremely high-density following fire.
But then there's another layer on top of it of pine pitch canker, which is a fungal pathogen; it's not native to this region. It spread into the post-Vision Fire bishop pine forest, and it's really having a huge impact on those trees, so there's a lot of dead trees and fuels because of that pathogen.
JRO: Pine pitch canker is yet another curveball thrown into the mix. The fungus is known to infect the bark of certain trees, including bishop pine. It leaves behind lesions, called cankers, that ooze with pitch. It might just kill off some needles, making the tree look sickly. But eventually, with enough of those lesions, it will kill the entire tree.
Before the Vision Fire, the forest would have been a stand of mature bishop pine trees. So, the conditions on Mount Vision today are actually quite a bit different than they were 25 years ago.
Even this scraggly forest of sick trees would eventually self-thin, perhaps leaving behind more robust bishop pines. There's some promising research that shows some bishop pine can become more resistant to pine pitch canker as they mature. But in the meantime, the overcrowded trees make this immature stand of bishop pine volatile. With such a dense and combustible source of fuel, I wondered how the forest ever reaches maturity without burning up along the way.
But fires started by lightning are not that common along the coast, especially compared with the rest of California.
AF: So that lightning event that started the Woodward Fire was, like, exceedingly unusual. We don't really have lightning very often on the coast, except in the winter, rarely, but usually it would be during a wet rainstorm event where it wouldn't start a fire.
JRO: There was a study that showed the fire history in Point Reyes using fire scars on big old redwoods trees and Douglas fir trees. The scientists found that over the last three hundred years, there was an average of two to twelve fires per year.
That's a lot more fires than there are lightning storms. Which only leaves one explanation—the same reasons that a lot of fires start: humans.
AF: You know, when Native Americans were managing the lands of Point Reyes, when the Miwok were managing those lands, they would have been using fire very often. So, there would have been, you know, every year fires burning within parts of the coast.
JRO: The Indigenous people that inhabited the land at Point Reyes for thousands of years before European settlers—they had it figured out. They cleared away the understory so it was easier to hunt. They knew where to burn and how often to support harvests of important food sources, like acorns. And they used it to maintain other stands of plants, ones that weren't necessarily food but were useful.
Today's scientists are still trying to catch up with that Indigenous knowledge of fire ecology, especially how it can be used for maintaining specific communities of rare and valuable plants. One of those scientists is Dr. Todd Keeler-Wolf. Before he retired last year, he was the Senior Vegetation Ecologist at the California Department of Fish and Wildlife. Now that he's retired, he's keeping busy by, basically working like he's not retired.
TODD KEELER-WOLF: As they used to say, it's keeping me off the streets
JRO: With the Woodward Fire still freshly smoldering, Dr. Keeler-Wolf was anxious to get in the park and see how it impacted rare or culturally valuable plant communities. I joined him and a group of visiting researchers to the park. The group included Brett Hall, the director of the native plant program at the UC Santa Cruz Arboretum…
[gravel crunching underfoot]
Unidentified voice [outdoors]: Banana slug!
JRO: and some of the students and contractors that work with the arboretum.
Dr. Keeler-Wolf created a way to classify vegetation habitats. A redwood forest, for instance, will have different plants growing in it than a bishop pine forest. With the classification system he created, scientists can map out areas with rare communities of plants around the state.
TKW: And, one of these is what we're standing in right now: the California hazelnut shrubland, widely used by Native American tribes in basketry.
JRO: California hazelnuts have long flexible stems. They grows in thickets. The leaves are round and have a toothy edge to them, and are velvety to the touch because of these small hairs. They're not uncommon to see here and there along a hike through a forested area in Point Reyes. And, in fact, despite their name, they aren't only in California—you can find them all the way up to British Columbia. But Dr. Keeler-Wolf says that it's rare to find a big patch of them, like the one we were standing in…or, at least, what was left of the one we were standing in.
TKW [outdoors]: Okay, so we're going to lay out this plot.
Unidentified male voice [outdoors]: Alright, so, give me a flag, any flag. I'll go…
Unidentified female voice [outdoors]: Should I put a point?
TKW [outdoors]: Yeah, this will be a nice, central location.
TKW: So, what we're measuring today is how much hazelnut got affected by this burn. There's a mark of a pretty high severity…local high severity spot. All the roots have burned out, all the ash is whitish and gray. And yet, if you go just a few feet, there is not much of a fire at all, and not enough to clear out the understory.
JRO: The group of researchers I was spending the day with want to know how fire impacts these plants. This was just one of their plots. At each plot, they measure the burn severity and what remains of the plants that were there before the fire.
Then, they hope scientists, like themselves or others, will revisit the plots at regular intervals in the future to see how the plants regenerate.
Dr. Keeler-Wolf says there's evidence that the coastal tribes would use fire to enrich and strengthen hazel.
TKW: So, resprouting, straight hazel net stems are the ideal basketry tool. And when they're burned, those new re-sprouts are particularly straight, they get more and more crooked with time and age.
I think what we're trying to tell anybody who's listening is: What happened after this fire? What kind of fire does it take to maintain this rare natural plant community? And what kind of fire does it take to make a useful, natural resource for traditional Native American uses?
JRO: Hazel isn't the only thing they're looking at in Point Reyes either. Dr. Keeler-Wolf says that the coastal prairie has also suffered without regular fire on the landscape.
TKW: That's another place that has been, sort of, in the past, managed by natural or native burning techniques prior to European colonization. And those coastal prairies have winked out, up and down the state, for a number of reasons, one of which is they've gotten invaded by shrubs because they aren't getting burned JRO: Like Dr. Forrestel said earlier, fire is an important way to keep these ecosystems thriving. These rare plant communities depend on it. So, having a fire come through at regular intervals is an important part of maintaining biodiversity.
And for conservationists, biodiversity is the name of the game. The more plants and animals that are thriving in a place, the better an ecosystem can bounce back from disturbances like fire. But even though fire can be a force for maintaining biodiversity, there's a balance. Even for the most fire-adapted ecosystems, too many intense fires can be a bad thing.
TKW: They could be threatened by high severity and high frequency. In other words, if it keeps re-burning every 10 years for 50 years in a row, so you have five burns, it's gonna exhaust a lot of the underground root carbohydrate storage that these guys have, and so they won't be able to come back.
JRO: One fear is that because fuel has built up on the landscape in California, the character of natural fire is changing. Too frequent. Too severe. Too intense. And that's disrupting the ecosystem, causing the communities of plants to change.
TKW: This whole notion of these strange, mega lightning storms—there's been a few of them now in the last couple of decades—and…four and a half million acres in one year in one state is a lot of acres to burn. And if that happens more frequently, you're sure as heck going to get a shift in some of the vegetation types.
JRO: But these ecosystems are also resilient. In my treks into the burned area alongside the scientists studying the impacts of the Woodward Fire, we all saw it: bright green growth. New ferns. Sprouting evergreen huckleberry out of charred stumps.
TKW [outdoors]: It's been three months since it burned, almost to the day, and its 35 to 40 centimeters long sprouts. Pretty good resprouting.
JRO [outdoors]: What's the common name?
TKW [outdoors]: Black huckleberry.
BRETT HALL [outdoors]: Yeah, it's definitely a champion
JRO: Dr. Keeler-Wolf finds that ability to rebound promising.
TKW: There's a lot of resilience in a lot of these plants. You look at these redwoods in California—these redwoods have been in California for millions of years and they used to be, you know, where Point Barrow, Alaska is now, you know, of course, back in, you know, the Late Cretaceous. And so, resilience is in our favor, because we've got such a variable landscape.
JRO: In the coming months, visitors to Point Reyes will get to see some of that resilience on full display.
AF: I think there's a good chance, if we get decent winter rains this year, that there could be a really nice wildflower display coming just this Spring, which would be really cool. And then, I think, in the coming years, you know, we'll see some dead Douglas fir trees. We'll probably see more ceanothus out there than we did before. It'll probably push the balance a little bit more towards grasslands in some places that were grassland-scrub mix. And, maybe, a little bishop pine expansion.
JRO: It's been a hard year. As we move into the early days of 2021, we're all looking for a reset. For new growth. Rest assured, the ecosystems in Point Reyes are pushing forward, just like the rest of us. More resilient than they seem. Greener days are soon to come.
Thanks for listening to The Natural Laboratory from Point Reyes National Seashore. This episode was created by me, Jerimiah Oetting. As always, a huge thank you to the Point Reyes National Seashore Association and the National Park Service for their support. And, all the researchers who gave me their time so I could create this episode.
This is the second in a three-part series about wildfire at Point Reyes National Seashore, so stay tuned for the third episode where we will look at how wildlife is impacted.
I'm Jerimiah Oetting, and thanks for listening.
[OUTRO MUSIC FADES]
JERIMIAH OETTING: Hey everybody, this is Jerimiah Oetting, the Point Reyes Science Communication Intern. Before we get started, I wanted to mention that we are recording this in mid-December, and as of now, parts of the park are still closed due to the Woodward Fire. Before planning a trip up to Point Reyes, be sure to check the park's website or its social media to see what's open. You can still access a ton of the park and have an awesome visit. Happy hiking.
JERIMIAH OETTING: You're listening to the Natural Laboratory from Point Reyes National Seashore. I'm Jerimiah Oetting.
SARAH ALLEN: (FADE IN) You see these oaks; this is a really old oak. It's probably a couple hundred years old.
JERIMIAH OETTING: This is a beautiful oak tree—
SA: It's a beautiful oak tree, and there are a lot of big oaks like this, like there's that one over there by the building, … (FADE OUT)
JRO: I'm walking with Dr. Sarah Allen. She's the former science advisor for Point Reyes National Seashore. We're talking about the Woodward Fire. It burned in the park last summer. She's showing me just how close the burn line got to Morgan Horse Ranch, only a short walk away from the Bear Valley Visitor Center.
The burned grass we're looking at wasn't actually caused by the Woodward Fire. It was started intentionally, by firefighters. It's called a backburn. It's one of the ways firefighters fight fire with fire. The backburn went up the hillside, burning up fuels until it met with the Woodward Fire, and stopped it in its tracks. The plan worked—no structures were burned in the Woodward Fire. Dr. Allen is showing me how bright green grass is already starting to sprout from the burn that firefighters started.
SA: (FADE IN) You can really see the line between burn and not burn, because while this old grass on the left was not burned and whereas on the right it's all emerald green, because that's where it burned down to nothing... (FADE OUT)
JRO: Dr. Allen just retired last year, after 26 years with the park service.
SA: Yes, I grew up in the area, so I spent a lot of time out at Point Reyes when I was a child. And I was able, very fortunately, to get a job with the National Park Service.
JRO: For many residents that live near Point Reyes National Seashore, like Sarah Allen, the Woodward Fire triggered memories of its predecessor—the Vision Fire. The Vision Fire was devastating. It spread fast. At its peak, it grew 3,100 acres every hour. Even though it was officially contained in just two weeks it burned over 12,000 acres. And it destroyed 45 structures—including many homes.
The Woodward Fire started just months before its predecessor's 25th year anniversary.
SA: It was interesting having to rethink about the Vision Fire because I went through both fires. And it brought up a lot of memories.
There were a lot of people who lost their homes, many of whom were friends of mine...just the…the long hours and the smoke and the stress.
JRO: The Woodward Fire was less than half the Vision Fire's size. Under 5,000 acres. Even though it persisted for over a month, the Woodward Fire was less destructive.
I spoke with Greg Jones, the fire management officer for Point Reyes. I wanted to learn why these two fires were so different. He says there are multiple factors
GREG JONES: The Vision Fire started in the fall when our fuel moistures are traditionally at their driest levels during the entire year. And then, there was an ignition, during a very strong wind event.
JRO: The Vision Fire started in a Bishop pine forest—trees that are extremely combustible. The Woodward Fire ended up in Douglas fir…
GJ: So much greener, wetter, heavy fuels, which still certainly burn, but it's just going to take a while to get through those fuels. You know, where it's like you see pictures of the old Vision Fire with kind of that scorched earth landscape. While there are certainly small patches of that in the Woodward Fire, a lot of it burned with very mixed intensities.
JRO: 2020 was a historic fire year in California. As of December 6, the state has had nearly 10,000 fires that have burned about four and a half million acres. It's the largest area burned in a single fire season in the state's modern history.
The infernos plaguing the state elsewhere include the August complex, the first giga-fire that burned over a million acres. Compared to these, the Woodward Fire was tiny. But it did threaten a community. There were so many other fires raging across the state, larger and more destructive ones, resources were stretched thin.
SARAH ALLEN: And that was also what was different because the Vision Fire was the only fire in the state at the time. And so, they were able to get many resources for firefighting here right away. And that did not happen right away with the Woodward Fire because they were competing with some really dangerous scary fires in other parts of the state.
JRO: In 1995, the Vision Fire was California's only fire. In October. At the peak of fire season. These days, that's hard to imagine. Every year, the fire season seems to get longer and more intense. So, what's the deal?
To find out, I spoke with Dr. Patrick Gonzalez. He's a forest ecologist and principal climate change scientist for the National Park Service, He said climate change and fire suppression are to blame.
PATRICK GONZALEZ: The two main factors driving the increase in wildfires across the Western U.S. including Northern California: the outdated policies of suppressing all fires, even natural ones. And, at the same time, the intensification of heat from human-caused climate change.
JRO: Temperatures are rising globally. That makes the hot and dry conditions that lead to wildfire more common. Point Reyes has already experienced an increase in average temperature of about two degrees Fahrenheit in the last century. But Dr. Gonzalez says heat isn't the only concern. Loss of moisture is also a problem. And the characteristic fog along Northern California's coast? That's thinning.
PG: Fog is the most important input of moisture during the summer. So, this combination of increased heat and reduced fog would tend to increase fire risk in Point Reyes National Seashore. The fundamental solution to reduce catastrophic wildfires is cutting the pollution from cars, power plants and other human sources that causes climate change.
JRO: Dr. Gonzaelz says fuel suppression is the other big issue. For almost a century, fire fighters have had a pretty straightforward policy: see a fire and put it out. Immediately. But that philosophy has left the flammable stuff that litters the forest floor to build up on the landscape. Now, it's at unnatural levels. And the West is a tinderbox. All it takes is a spark to set the whole thing off.
Because 2020 is 2020, California got a little bit more than a spark this year. An unprecedented lightning storm shocked the state in August. 12,000 lightning strikes, causing 585 wildfires. The Woodward Fire was just one of them.
We might not be able to control the lightning. But Gonzalez says we can support policies to reduce global warming. And, we can reduce fuels on the landscape. Ironically, one of the best ways to prevent catastrophic wildfires is to let fire do its thing, as much as possible.
PG: Wildfire is an essential and necessary and natural part of many forest and woodland ecosystems across the western US, including in Point Reyes.
JRO: Fire returns nutrients held in vegetation back to the soil. And some species, like Bishop pine, require fire to reproduce. They have "serotinous" cones, meaning their cones don't open unless immersed in the heat of a flame. In shrubby, non-forested areas, the plants depend on regular fires to revitalize the ecosystem and stay healthy.
Greg Jones says they've used fires in the Olema Valley, to reduce fuels, and kill French broom, and invasive shrub. It's a couple hundred acres they burn about every five years.
GREG JONES: In fact, we had some burning planned for this year. But obviously, the Woodward Fire kind of commanded our attention this year, so, we'll hope to get to those next year.
JRO: But he said lately, that has gotten harder.
GJ: Our biggest challenge to even pulling off our burns that we have planned right now, is really our, uh, the windows, um, of opportunity seem to be getting smaller than they used to be.
JRO: To burn safely requires just the right conditions. Usually, the best days are right after the first rains of fall. And because smoke is a concern, a burn requires approval from the Bay Area Air Quality Management District.
GJ: In several recent years, we've gone from, you know, kind of crazy high fire danger, and very destructive fires, you know, just to the north of us. And then it starts to rain. And so, we don't really get that good in-between window.
JRO: Long fire seasons aren't the only obstacle. Jones says there are many areas in the park that are simply too dangerous for a prescribed burn. Like, the stands of bishop pine trees that regrew after the Vision Fire.
GJ: So, there's a large dead and dying component to that forest. Right up along community boundaries. And I'd say, that presents us with some challenges.
The Bishop pine system is a stand replacement fire regime, which means the whole forest is designed to burn. It burns 100%, and so what comes up in the wake of an event, like the Vision Fire, is in an even-aged forest, and it comes up very dense.
JRO: The overcrowded trees compete for limited resources. As a few of them start to dominate, the others die. Jones calls it "self-thinning." It's a natural process. But other stresses, like drought and disease, kill even more trees than usual. What's left is a forest full of fuel.
In those areas, mechanical thinning is the best approach. Jones says they're working on a large fuel break along the community boundary with the park. He calls it a shaded fuel break. They leave large, dominant trees, and remove as much other fuel as possible. And they limb lower branches. That prevents a ground fire from climbing into the crowns of the trees, where it can spread more easily.
Dr. Sarah Allen lives in Inverness close to the park. She says people in the community are wary of more fires, even intentional, controlled ones. The smoke is bad, for one thing.
But living in this part of California, surrounded by fuel, requires making a tradeoff.
GJ: We're not gonna be able to, like, erase fire from Marin County or from a forest, any more than we would be able to stop, like, a flooding event or an earthquake. These fires are gonna burn.
JRO: After living through the Vision Fire, Allen has learned how to be more prepared.
SARAH ALLEN: I have a much healthier respect for living in the community, and how to protect our home and landscaping. So, I do exactly what the Marin County fire crews tell us to do in clearing. And I have a go bag that I have active year-round. Here we are, in December, and we just had a red flag day. So, I have my go bag out ready to go. And I have my evacuation plan that I would never have thought about when I lived before the Vision Fire.
JRO: In the end, Jones says the Woodward Fire was a success story. No homes were lost, there were no serious injuries to the public, or to firefighters.
GREG JONES: We're able to manage long term fire. You know, we'll see, but, you know, perhaps some good ecological benefits, you know. I still acknowledge that there was certainly a large impact on the community in terms of the evacuations. And then the smoke impacts were very real, for quite a long time. You know, not trying to, like, minimize that, but, you know, overall...we did pretty good on this one.
JRO: For California's worst fire season in modern history, and for the rest of 2020, pretty good is about as good as it's gonna to get.
JRO: Thanks for listening to the Natural Laboratory from Point Reyes National Seashore. The music for this episode, the writing, editing, and production, were all done by me, Science Communication Intern Jerimiah Oetting. Thanks to Dr. Sarah Allen, Dr. Patrick Gonzalez and Greg Jones for their time. And a huge thanks to Ben Becker, Heather Clapp, and everyone at the national park and Point Reyes National Seashore Association for all their support. I'm Jerimiah Oetting and thanks for listening.