A colleague’s perspective on the 2017 offering of my summer “Landscape Change” course in Olympic National Park

Reflections on 9 days in the wilderness with Tim Billo [reblogged from UW Environmental Studies Website]

For a trip of a lifetime, School of Marine and Environmental Affairs student Katie Keil rearranged her travel to join Tim Billo and his ENVIR 495C: Landscape Change in the Pacific Northwest course as a teaching assistant. The annual summer course has deeply impacted students who have, for perhaps the first time, experienced raw wilderness and learned about what a changing landscape means for us all.

In Katie’s words: “Although the views were spectacular, my favorite times were the evening thought provoking, student-led discussions about our wild lands around a fire (including some ghost stories).  We explored topics of wilderness preservation, minority access to national parks, and the impacts of changing environments in the Anthropocene.”

Read more about Katie’s experience here and see posts from the student blog. Instructor Tim Billo offers this course as one way for students to interact with nature on an intimate level and says “extended wilderness travel offers us rare time and space to think deeply about how we might move forward as a society at this critical juncture in earth’s history, the beginning of the Anthropocene era.”

 

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In the news: Sword fern die-off

Our work on sword fern die-off was picked up by several news agencies this summer including King 5 News and the Associated Press. KUOW’s Eilis O’Neill did a nice radio piece which included the voices of my kids on a hike through the die-off zone (see photo below). Sierra Magazine also did a nice piece highlighting the role of citizen naturalists as “canaries in the coal mine” for ecosystem health and degradation.  In this context, my students and I, along with a number of dedicated citizen scientists, have been following up on crucial observations made by a neighborhood naturalist, Catherine Alexander, in 2013. The upshot of this media coverage is that many concerned folks have come out of the woodwork to inform us of other sword fern die-off locales around the region. My students and I will follow up on some of these new sites, setting up sampling and monitoring protocols in those locations, while continuing the work in Seward Park.

For summaries of the sword fern die-off problem, see my earlier posts.

A photo taken by Eilis O’Neal (courtesy of KUOW) during our radio interview in the fern die-off zone.

Seward Park Fern Die-off Update

In my last post on the sword fern die-off phenomenon, we reported that the problem was getting worse. Another year has gone by and my students have continued to monitor the die-off, giving us 2 years of data.  Here  (link takes you to slides put together by my undergraduate students Tristan O’Mara and Kramer Canup), based on our most recent survey data collected in October 2016, we report the same thing again. All of our study plots had a net loss of ferns, with 30% increase in outright dead ferns across all the plots from 2015 to 2016. The affected area of the park has doubled in size from 5.7 acres in 2015 to 11 acres in 2016. Qualitative observations in the spring of 2017 suggest that the die-off continues to spread throughout the park. We continue to monitor the ferns and we hope to have a new quantitative update in the fall of 2017. Additionally, we have located other sites in Seattle and the Puget Sound Region that seem to be exhibiting signs of the same die-off.

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Left: Healthy sword fern understory in Seward Park, taken in 2011. Right: The same area is almost devoid of ferns in the 2017. Both photos were taken at roughly the same time of year. Thanks to Jordan Jackson (left) and Paul Shannon (right) for photos.

In a related study, my student, Justin Beach, has set up exclosures to test the effects of herbivory by native mountain beavers (Aplodontia rufa) on sword ferns in Seward Park. Seward Park is one of the last places within the city of Seattle to host populations of this unique burrowing rodent endemic to the Pacific Northwest. While there does already seem to be some noticeable effect of beaver herbivory on ferns in the control plots, we remain dubious that mountain beavers are the root cause of die-off, namely because die-off also seems to be occurring at other sites where mountain beavers are absent (not to mention that die-off is not occurring in many other places where mountain beavers are present–the ferns and beavers have probably co-evolved and successfully co-existed over millions of years). The rationale for studying mountain beavers in Seward Park is 1) there has been little work done on the effects of mountain beavers on ecosystem structure anywhere, and 2) predators of mountain beavers have been absent in Seward Park for some time, so it is possible that mountain beaver densities in the park are artificially high, leading to more extreme negative effects on their primary food source (sword fern). If the die-off continues at its current rate, however, it raises the more alarming prospect that one of the last remaining populations of native mountain beavers within the Seattle city limits will become endangered due to loss of ferns, one of their primary food sources, especially in winter.

ENVIR 280 BioBlitz at SkyRoot Farm!

Here, finally, is a summary of our ENVIR 280 spring field trip (May 7, 2016) to Beth Wheat’s SkyRoot Farm on Whidbey Island. This was a unique field trip for us because, unlike our other trips to more “pristine” habitats, this foray explicitly sought to describe the natural history of an actively managed landscape. Given that the number one reason for loss of natural habitats across the globe is the development of human agriculture, understanding the effects of agriculture on nature and ecosystem function is critical.

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Beth gives the grand tour to get us started. We were also accompanied by former PoE director, Johnny Palka.

We surveyed the farm,  from the intensively managed farm fields to the surrounding meadows and forest fragments which buffer the property. While we only spent a few hours on the farm, we were surprised by what we found in this working organic farming landscape.  Hopefully our report can serve as a baseline as Beth grows her farm, restores the surrounding habitats, and generally seeks to make her farm more ecologically integrated into the natural landscape.  Here’s our report:

Whidbey Island is famous for its glacial geomorphology. SkyRoot Farm sits at the base of a drumlin. Forests on the edge of the farm creep just up the base of the drumlin. Soils in this section are sandy, and resemble the advance glacial outwash (Esperance sand) so prevalent in Seattle.

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SkyRoot Farm is located on the west side of the eroding drumlin which is crossed by French Road.

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Sandy soils in the forest on the slope of the drumlin. These are glacial outwash sediments from the advance of the Vashon icesheet.

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The farm is on a flat clay soil area on the west side of the drumlin. Clays were deposited in slow moving waters early in the advance of the Vashon icesheet. A creek originating from the porous soils of the drumlin, flows across this flat area, unable to percolate through the clay layer. Large cedar stumps (cedar trees being tolerant of wet soils), such as the one in this picture, remnants of the original oldgrowth forest, are visible on the landscape, sometimes overgrown, in places that were never intensively farmed. The meadows on this clay layer are naturally very wet, owing to the fact that water percolating through the drumlin is forced to flow outward along the impermeable clay layer. They are dominated by rushes (Juncaceae).

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The riparian habitat running through the farm is home to a variety of native wetland plants, including Tolmiea menziesii (pictured here), Rubus spectabilis, sedges (Carex sp.), Alnus rubra, Sambucus racemosa, common horsetails, lady ferns, Tellima grandiflora, and Lysichiton americanus (skunk cabbage). Licorice fern grew on big leaf maples, along with a variety of common pollution tolerant lichens. such as Evernia prunastris (antlered perfume), Usnea sp. (perhaps blood spattered beard), various dust lichens, and “forking bone” lichen.

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We identified this Ribes divaricatum, one of many gooseberry species in WA, (spines in clusters of 3 being diagnostic) along the creek.

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Coyotes are active in the riparian strip, a sheltered habitat for mammals to move through the agricultural landscape in secret. We will place camera traps here in the fall to confirm this identification.

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Banana slugs in the riparian strip: Denizens of the surrounding conifer forest fragments, they make their way into the farm landscape via the riparian corridor. This native species is absent in most of Seattle’s forest fragments, replaced there by a European species that probably has some negative consequences for the health of our forests.

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Amphipods were abundant in the creek.

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Red legged frogs were abundant in the riparian strip. This species has experienced significant declines in Oregon and California due to habitat loss, introduced bullfrogs, UV and more. It will be important to continue monitoring for this species. Tree frogs are also abundant on the farm. We recently found some on our fall trip to set up camera traps.

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Trientalis borealis ssp. latifolia (Starflower, Primulaceae) is a common flower of the floor of conifer forests from sea level into the mountains.

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Red legged frog, again.

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The red admiral, a common butterfly of open areas. Larvae feed on nettle. Adults feed on nectar.

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This Douglas fir stump is healing itself. Is it connected to living trees via mycorrhyzae? Sword fern is adjacent, with dull Oregon grape behind. Red huckleberry was also abundant in the woods. There is much potential on the farm for harvest of native perennial “crops”. In this second growth forest, the canopy is still fairly closed, and the forest floor is fairly devoid of plants. The forest has already gone through its self-thinning phase, however, and is beginning to show some more diverse structures. On our fall trip to set camera traps, we found a Barred Owl in this forest. We also noticed the invasive English Holly and endeavored to pull it out whenever we could.

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The goldenrod spider on a vetch. This gorgeous spider is sitting in wait of its prey, perhaps a bee that would otherwise pollinate this flower (I have seen this species take bees before!).

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Hannah holds a song sparrow, a common bird of forest edges.

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One of the many insects we found on the farm (Carabus granulatus). This ground-dwelling beetle, found in both forest and field, is generally thought to be useful in controlling pests. Invertebrates are its main food in both larval and adult stages. We also found another invertebrate predator, the blue-eyed darner dragonfly, engaged in its amazing copulation flight. The fact that Beth’s farm is organic serves these predators well. The Carabus is particularly sensitive to pesticides.

Here’s our complete bird list (not bad for a few hours, and indicative of the variety of habitats available at SkyRoot, from conifer forest, to alder forest, to riparian, to open meadow):

Barn Swallow
House Sparrow
Song Sparrow
European Starling
American Robin
American Goldfinch
Black-headed Grosbeak
White-crowned Sparrow
Violet-green Swallow
Hutton’s Vireo
Common Yellowthroat
Steller’s Jay
Pacific-slope Flycatcher
Chestnut-backed Chickadee
Northern Flicker
Bewick’s Wren
Common Raven
Purple Finch
Anna’s Hummingbird
Dark-eyed Junco
Spotted Towhee
Red-breasted Sapsucker
Pileated Woodpecker
Downy Woodpecker
Olive-sided Flycatcher
Osprey (flying by)
Turkey Vulture (flying by)
Red-tailed Hawk (flying by)
Bald Eagle (flying by)
Yellow-rumped Warbler

Western Wood-Peewee

Add: Barred Owl in fall, and in later spring/early summer, Red-Winged blackbirds, Townsend’s Warbler, and Western Tanager. Undoubtedly there are many more birds that use or pass through the farmscape throughout the year.

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The Puget Sound Region loses two giants in natural history: Art Kruckeberg and Bob Paine

With a new quarter in ENVIR 280 (Natural History of the Puget Sound Region) upon us, I wanted to take the opportunity to reflect on the lives of two giants in the natural history of our region, Bob Paine and Art Kruckeberg, both of whom passed away earlier this year while I was busy teaching the spring version of ENVIR 280. I will not attempt full obituaries here since there are many excellent obituaries available on the internet by people who knew them better than I. Instead I will briefly describe their connection to ENVIR 280 and what my brief interactions with them have meant to me.

Art Kruckeberg:

I will start with Art Kruckeberg, whom I unfortunately never had the chance to converse with, but whom I had the pleasure to hear from in a graduate student seminar at the University of Washington, probably 15 years ago now. He, of course, waxed poetically about serpentine plants, but I believe the topic of his seminar had more to do with his work on Achillea with the famous botanical triumverate of Clausen, Keck, and Hiesey. I was completely enthralled, not only to learn more about the importance of their seminal study on Achillea ecotypes (work I often talk about now when in the field with students), but to learn more about the logistics, places, and personalities involved; and  to hear about it directly from someone who was there (especially from someone who is a legend in his own right) felt like I was immersed in the history of science–a heady experience for a beginning graduate student such as myself.

But my present career has benefited from Art’s legacy in some more tangible ways. It was Art who taught the original “Natural History of the Puget Sound Region” course at the University of Washington. It may have been taught under a slightly different title at the time (and I’m guessing was probably biased towards geo-botany, a field that Art popularized), but when Josh Tewksbury re-invented the course in 2012, it had probably not been taught for over 20 years because the UW (like most major universities) had lost its appetite for general natural history courses. I occasionally meet older folks who were students in UW Botany back in the day, and they rave about their time in the field with Art in this class. The class apparently had field trips to far-flung parts of Washington every weekend (unfortunately our budget and changing times limit us to only three weekend field trips). So, I feel in some way teaching ENVIR 280 today, that I am carrying on a legacy begun by Art. Art’s book, “Natural History of Puget Sound Country”, upon which the curriculum of our course is partially based, is unparalleled in the depth and breadth of its approach to the natural history of this region (ranging from geology, botany, and zoology, to the ecology of first peoples). Indeed, I don’t think there are many regions of the U.S. or world that have a tome quite like Art’s to describe their own natural history.  Art, and his commitment to making the general natural history of this region accessible to a wide audience, will be missed. Thankfully he left many students who are carrying on the tradition (including the entire Washington Native Plant Society, which Art helped to found). And I look forward to visiting the Kruckeberg Botanic Garden, another legacy left by him and his wife.

A familiar photo of Art in the field–the same photo that graces the back cover of his famous book, “Natural History of Puget Sound Country”. Photo courtesy of http://artkruckeberg.com/

 

Bob Paine:

The second giant I want to talk about is Bob Paine, a scientist and naturalist whom I had the pleasure of getting to know later in his life, as a fellow participant in the Natural History Network’s workshop on Natural History Education at UW’s Pack Forest (in which he candidly discussed creating an environment in which his children could get dirty and freely explore nature–in this case the creeks and ponds of the UW Aboretum–an idea that I have heeded now that I am a parent myself), and through his participation in ENVIR 280 as a guest lecturer. The photo below, by Benj Drummond, is from the Natural History Network workshop.  One of the best outcomes of that workshop was the Natural Histories Project, in which Bob’s voice is immortalized as he holds forth on the longevity of sea anemones:  http://naturalhistoriesproject.org/conversations/anemone-like

Bob Paine, at the Natural History Network’s education workshop. Photo by Benj Drummond.

As a graduate student in UW Biology, I passed Bob’s emeritus office space (more like a small room by the backdoor of the building) almost daily. His door was always open in invitation to students to drop in at any time, even as he worked tirelessly on manuscripts and lectures. He was also a frequent participant in the weekly graduate ecology seminar, which he started long before he retired, and which he attended long into retirement (apparently even emailing his thoughts into the seminar during his final days when he was too sick to attend). Bob was one of those people who seemed “anemone-like” (in reference to the recording linked above). I fully expected him to be in that office forever, holding forth on any manner of ecological or natural history topics with whomever might stop by. For a man of his age, he maintained excellent physical health, and his mind remained as sharp as ever even as his body aged. I was shocked to learn that Bob had been dealing with cancer and that he had passed away relatively suddenly this spring.

It wasn’t until after the Natural History Network workshop that I felt more comfortable just dropping by and chatting with Bob, and I got to know him much better in the process. True, he was a giant in the field of ecology, as many of his obituaries demonstrate, but he was easy to talk to, extremely self-effacing, and willing to mentor anyone (from undergraduate to postdoc) who might wander into his office, with incisive and insightful advice. As an example of his modesty, a student in one of my natural history classes asked him after an engaging guest lecture on his ingenious studies of intertidal ecosystems, whether he had received any accolades for his work. Bob sheepishly replied that he had received a few, but quickly returned the subject to natural history.

As a naturalist, Bob got his start studying birds. At the Natural History Network workshop, I recall the fish biologist, Mary Powers, saying that Bob was able to double her house bird list, just by sitting on her front porch and listening to the songs of birds calling from the vegetation nearby. But, as a biologist, Bob wanted a study system that he could more easily manipulate. At the University of Washington, he settled on the ecology of invertebrates in the rocky intertidal zone of Washington’s outer coast, also the subject of his guest lectures in my class–usually to prepare us for our big spring field trip to rocky intertidal ecosystems.

In the first few iterations, Bob’s guest lectures were done with an old- fashioned slide projector (although I think in the last iteration, he had scanned his old slides into a PPT), as he took us (the audience) on a virtual tour of his beloved Tatoosh Island. Bob was convinced that advances in biology came from careful observation of nature, rather than reading books or papers. More importantly, he taught my class that the best naturalists turn their observations into questions, and then answer those questions by devising simple experiments. He walked us through his thought process on Tatoosh, starting with basic observation of the natural history of common organisms, and then asking questions about what controls their distribution and abundance in the intertidal zone. He encouraged us to always ask ourselves in the field which ecological force(s) (disturbance, predation, herbivory, competition, facilitation, uncertainty or randomness) best accounted for patterns we might be seeing at any given time. He showed us “before and after” photos of winter storm wave action on Tatoosh. He showed us coralline algae growing over a sponge, competing for space. One of my personal favorites was his image of an algae garden maintained indirectly by a black oyster-catcher preying on limpets and other algae grazers–an example of a trophic cascade. And of course, no Paine lecture would be complete without a discussion of ochre sea stars as a keystone species (a term he essentially coined), and its ability to structure and maintain diversity in the system. He described how he tested his ideas using simple, yet ingenious experiments, using supplies from hardware stores and marine supply stores to either enclose or exclude organisms on the rocks, in addition to simple removal experiments. He brought in a veritable museum of beat-up experimental detritus left over from these experiments, explaining that all of these things were acquired cheaply and easily, the only tricky part being finding items that could withstand wave action day in and day out.  The takehome message was that these experiments could have been done by anyone who was willing to observe and think–money was not the limiting factor. Of course, being the first person to do the “observe and think” part, was no small task. Perhaps this is just another example of Bob’s humbleness.

In later iterations of Bob’s guest lecture to my class, he became increasingly concerned about human-induced stressors on ecosystems and he was convinced that natural history and experimental ecology might be used to predict future ecosystem structure. For example, if humans over-harvest algae, or grazers such as abalone, an understanding of the effects of herbivory and competition in a given system would be crucial to predicting how the system might react. He had also become increasingly concerned with Seastar Wasting Disease (which is actually probably not directly human induced), which, as a result of his own experimental work, might arguably cause mussels to become more common in their place. But he was quick to point out another new human-induced stressor, ocean acidification, which may simultaneously negatively effect mussels (by inhibiting their ability to grow byssal fibers), particularly in cold waters at higher latitudes.

Bob was convinced that intensive study at one site (in his case, Tatoosh Island) is essential for field ecologists to undertake. While some might criticize the ability to generalize results from only one site to other sites, the depth of knowledge one can obtain by studying a single site for a long period of time is simply unmatched by short studies across many sites. Using one site for a long period of time, one can tease apart complex interactions by really getting to understand the ecology (starting with basic natural history) of many of the players in the system through time. And it is the time component that is most important. Organisms that you think are the major players ecologically in the system today, may not have been in the past, and they may not be in the future. A long time-base allows you to understand natural variation in the system, and it is the only way that you can begin to tease apart natural variation in the system from the many human-induced variations that systems are likely to incur in the future.

For as proud of his experimental ecology work as Bob was, in one of my last interactions with him, he loaned me a book with a section entitled: Food recognition and predation on opistobranchs by Navanax inermis (1963). In this section he essentially follows a single sea slug around the intertidal zone for what must have been days on end recording a careful diary of where it went and what it ate for as long as he could stay with it. This, to me, demonstrates Bob’s dedication to not only experimental natural history and ecological process, but to the most basic kind of natural history observation. This is the kind of work that ordinarily would never make it into a publication in today’s scientific arena, and is thought of as old-fashioned, or even a death-knell to anyone who wants a career in modern biology. In this chapter, Bob unabashedly provided simple documentation of the life of an organism that most people have never heard of, let alone care about, but that deserves to be paid attention to every bit as much as any other organism on the planet.

Bob will be much missed, but his enormous scientific and teaching legacy will live on. I hope that I can do justice to this legacy as I strive to pass on his ideas and wisdom to my students.

Seward Park’s Sword Fern Die-off: the problem is getting worse

Note: For an update on this issue, see this new post.

This post documents a research project I have been heading, with the help of University of Washington undergraduates, and a group of concerned citizens from the Seward Park neighborhood.

Seward Park is one of Seattle’s flagship parks, and one of only 2 parks I know of in Seattle that has any substantial remaining old-growth forest. In 2013, Catherine Alexander, a local citizen naturalist and daily user of Seward Park, noticed that Sword Ferns (Polystichum munitum) were mysteriously dying in the understory of Seward Park’s old-growth. A frequent park user myself, having recently moved into the neighborhood, Catherine p0inted out the problem to me in the winter of 2014/15. I was convinced the ferns would make a comeback in the spring, but I was surprised when nature proved me wrong. While several other local citizen naturalists sensed the problem was worsening, no one had actually taken the time to quantify the extent of the damage and spread of damage, let alone address the causes. In 2015, Paul Shannon, a leader of a citizen group called  “Friends of Seward Park”, enlisted me to help get a handle on the problem.

With the help of two excellent undergraduates from the University of Washington, Kramer Canup and Tristan O’Mara, we began to consider experimental designs for monitoring the current extent of damage and change in damage over time. While we considered a gridded plot system which would cover areas inside and well outside the die-off zone, as well as a protocol for fine scale transects crossing the perimeter of the die-off area (to detect expansion of die-off), limited time, funding, and human power caused us to settle on more minimalist protocols.  To map the perimeter of the damaged area (interestingly, the damage seems to be worst at central point, and is spreading radially from that point, rather than patchily throughout the forest), we used GPS and GIS to mark and connect points at which 50% of the individual ferns in a given area exhibited at least 30% dead fronds (Figure 1). To better understand the dynamics of the die-off over time, we randomly placed 20 plots inside and just outside the perimeter of the damage zone (Figure 1). Within each of these plots, we mapped every fern and counted fern stems categorizing them as living (if they had any amount of green coloration at all) or dead (if they had no amount of green coloration). Adjacent to each plot, we also sampled for fungal pathogens on fern roots in collaboration with the Washington State University extension program. All plots were surveyed in November 2015 and again in May 2016 (see results below). We hope to repeat all of these protocols again in November 2016 and again in 2017.

We randomly placed 20 5m x 5m plots throughout the region of fern damage in Seward Park. The red line polygon encloses the area of worst damage, approximately 100% die-off, first noted in 2013. The black polygon marks the outer edge of fern die-off according to a protocol we developed. Blue plots are plots that gained fern stems between November 2015 and May 2016, and red plots are plots that lost fern stems over the same period.

Figure 1. We randomly placed 20 5m x 5m plots throughout the region of fern damage in Seward Park. The red line polygon encloses the area of worst damage, nearly 100% death of all sword ferns, the area in which die-off was first noted in 2013. The black polygon marks the outer edge of fern die-off according to a protocol we developed. Blue plots are plots that gained fern stems between November 2015 and May 2016, and red plots are plots that lost fern stems over the same period.

Tristan Kramer counting healthy ferns

Tristan O’Mara and Kramer Canup (UW undergrads) surveying ferns in November 2015, in a healthy sword fern understory.

Tristan KRamer ground zero

Tristan O’Mara and Kramer Canup surveying ferns in a plot at the center of the die-off zone. Nearly 100% death of the ferns is observed here. Prior to 2013, the understory in this area looked much like the understory in the image above. The density of dead fern fronds in this area rivals the density of live fronds in the area pictured above.

laying out plot at ground zero

Laying out the plots, and staking the corners. November 2015.

After the resurvey of the 20 plots in May 2016, some initial results are in. The punch-line is that some plots/ferns gained green stems (not surprising in the spring-time), but most plots/ferns lost green stems (surprising given that it was spring). On average, there was an 18% loss of green stems (p<.002) across all of the ferns across all of the plots (Figure 2).

Figure 2. The average number of live stems per fern declined by 18% from November 2015 to May 2016. This is especially surprising given that our 2016 resurvey was in the spring. One would expect a brief uptick in green stems in spring, prior to the typical summer drought.

Figure 2. The average number of live stems per fern declined by 18% from November 2015 to May 2016. This is especially surprising given that our 2016 resurvey was in the spring. One would expect a brief uptick in green stems in spring, following typical summer die-back in the previous growing season.

Mountain Beaver ferns

Figure 3. Sword ferns neatly snipped and stacked at the entrance to a mountain beaver burrow in Seward Park.

While documenting the status of the die-off has been an important first step, there are many possible reasons for the die-off.  Unfortunately, we have very little insight into the reasons. 2015 was an unusually hot and dry year, but the problem began under normal weather conditions in 2013. Still, we may see some recovery following this summer (yet another reason to continue monitoring).  Testing for pathogens in the soil and root systems has yielded negative results. There are some pathogens there in small quantities, but not in quantities expected if they were the sole cause of the die-off. Die-off seems to be worst on an east-facing slope that is riddled with mountain beaver (Aplodontia rufa) burrows. Sword fern is one of their favorite foods, as evidenced by the photo above (taken in an area of healthy fronds neighboring the die-off zone)(Figure 3). I hypothesize that mountain beavers (largely unchecked by predators in Seward Park) may be part of the issue here. I have found other areas in the park that show evidence of historical sword fern die-off, and my sense is that predators such as coyotes, which come and go from the park over time, may cause ups and downs in the beaver populations. Currently, there are no coyotes known to be using the park.

Future work: With the help of Patrick Tobin (UW College of Forest Resources) and graduate students, we will expand the plot system we have already established, monitoring and mapping ferns and overstory trees.  We plan to take a detailed look at soil arthropod communities inside and outside the die-off zone. We will monitor soil nutrients and soil moisture in a methodical way inside and outside the die-off zone. We will continue sampling for pathogens. And most importantly, we will begin a sword fern planting experiment, using a paired design (in which each treatment is paired with a control), with possible treatments including mountain beaver exclosures and fungicide application.

I believe that systematic monitoring and experimentation are an important step forward for understanding the ecology of Seattle parks. Amazingly, there is very little of this going on in Seattle’s parks, given the value of these natural spaces to the city. Volunteers donate countless hours to restoration projects and general stewardship, but we need to keep track in a quantifiable way, of how successful these efforts are, in order to get a better handle on the health of our natural spaces. With respect to the sword fern die-off, at this point in time we simply don’t know enough to justify gathering a restoration crew and re-planting the area with sword ferns. Due to lack of systematic monitoring across Seattle parks, we don’t even know if this sort of die-off is occurring in other Seattle parks (although as far as we know it is not).

Going forward, we will need help in the form of human power (undergrads, grad students, citizens?) and funding. Contact me at timbillo (at) uw.edu if you’d like to help

 

 

In the news: Lynda Mapes of the Seattle Times, covers ENVIR 495C

Lynda Mapes of the Seattle Times recently covered my summer course with this excellent article and video.

The group poses on Grand Peak (photo by Steve Ringman of the Seattle Times)

The group poses on Grand Peak (photo by Steve Ringman of the Seattle Times)

Or paste this link into your browswer:

http://www.seattletimes.com/life/outdoors/students-trek-a-reset-for-the-human-spirit-as-national-park-service-turns-100/