A Mountain Lion Prowls the Neighborhood

There’s a place along the Skagit River where I like to wander. Upstream and downstream, the river is lined with rural home sites, but in between there’s a small pocket of undeveloped land where relatively few people go. Compared to the wild lands surrounding nearby Mount Baker and the North Cascades, it’s a small area and nothing close to what most people would consider wilderness. A regenerating clear cut sits on a terrace above the water. Below it, the river flows through a shallow S-curve and a swampy area occupies the annual floodplain. Filled with a willow thicket, it’s a good place to hide, for me as well as many other animals.

I’ve made it a habit to explore the animal trails leading in, out, and through the floodplain. In the spring, when the water table is higher, Pacific tree frogs spawn in ephemeral pools. In fall, a black bear visits the riverbank to scavenge spawned-out salmon. All year, elk use it to move between pasture. I frequently see sign left by coyotes, and if I look hard enough I might be able to find the tracks and scat of bobcats. While I rarely see the live animals, exploring their haunts helps keep me connected to the other creatures that I share this place with. I have a spot within this area where I like to sit and listen, but sometimes the most interesting observations happen upon my approach and exit into this little pocket of wilder land.

Following an elk-maintained path down to the riverbank, I exited the forest onto a muddy side-channel, now mostly dry after a long, arid summer. The exposed mud and sand of late summer offer some of the best tracking opportunities of the year. I slowed my pace, eager to see which animals had moved through the area recently. In the semi-firm mud, I stumbled upon a set of feline tracks. The tracks were large, as wide as the palm of my hand with four clear toe prints. There were no claw marks and the sizable metacarpal pads were distinctively three-lobed at the base. These belonged to a mountain lion.mountain lion tracks in mud. Notebook is approximately 7 inches wide.mountain lion track in mud. track point towards right. Notebook is approximately 7 inches wide.mountain lion tracks in sand. tracks point towards notebook at bottom of photo. Notebook is approximately 7 inches wide.Curious to know more about its travels here, I followed the tracks along the edge of the river. The cougar followed the same general path I would have to move upstream; it stuck to the mud and driftwood on the edge of the willows. From the additional tracks I was able to find, the cougar continued along the riverbank for another hundred yards before I lost the trail in the adjacent thicket.

Based on my completely unscientific survey of mammal sign in the surrounding few acres, elk seemed to be the most abundant large animal here. They left many sets of tracks that moved perpendicularly from the river and into the deep cover provided by the willows. Was the lion stalking potential prey, or was it simply wandering through? Could a kill site be nearby? My imagination ran with the possibilities, but the dense vegetation would effectively hide any further evidence of the lion’s travels—unless I was lucky enough to stumble upon more sign.

Discounting that possibility as too unlikely, I left the river by following a narrow elk trail lined with salmonberry. The trail led, in a convoluted manner, to my sit spot where I sat for while to jot a few written notes and listen to the forest.

forest scene with taller trees in background and many small shrubs in foreground

To head home, I took a different yet familiar route along more elk trails. By this time, I wasn’t expecting to find any more sign of cougars (the duff was too well compacted and dry to hold their paw prints), but when I reached a fork in the trail I found evidence that at least one cougar had visited the area several times. Under low hanging branches of western red-cedar were four large scrapes. Each scrape was oblong and about a foot in length. Each had a small pile of debris at the base and three were accompanied by scat.

photo of mountain lion scrape in forest litter. notebook at bottom left is about 7 inches wide.photo of mountain lion scrape in forest litter. notebook at bottom left is about 7 inches wide.

Mountain lions are reported to urinate when they make scrapes, but I couldn’t detect any strong urine odor despite kneeling down for a better waft. Evidently, the cougar had been here several times, but not that day and perhaps not even the past week. It looked to be eating well when it was here though. One pile of scat was sizable and reflective of a diet heavy with meat.

I found no other mountain lion sign that day, but the scrapes and tracks caused my mind to again race with the possibilities of its life here. Did it make a kill nearby? Or, was it merely using the heavy cover as a secure place to rest between meals? I left with more questions than answers. This mountain lion’s story might be missing some pages, but sometimes the finer details of a good tale are best left to the imagination.

The Worst Place in the World for a Mine

“This is the jewel in the crown of America’s fisheries resources – these salmon. If you don’t think this is worth saving, what is? To me, if you don’t draw a line in the sand here, there’s none to be drawn anywhere.”

Thomas Quinn
Professor, University of Washington and author of The Behavior and Ecology of Pacific Salmon and Trout

After more than a decade of controversy, Pebble Mine is inching closer to reality, and from the perspective of salmon, we couldn’t choose a worse place for an open pit mine.

red salmon swimming in shallow water

If you’re unfamiliar with Bristol Bay, its salmon, or Pebble Mine, please watch this 2012 overview on the Pebble Mine controversy, keeping in mind the mine’s currently proposed size and mineral processing plans are different than those outlined in the video.

Pebble Mine is a proposed open-pit copper, gold, and molybdenum mine at the headwaters of some of the last intact and most productive salmon habitat on Earth. Before any development of the mine can begin however, it must be permitted, and before it can be permitted, it must undergo an extensive environmental review. This is where we stand currently: the environmental impact statement (EIS) process for Pebble Mine has begun.

An EIS goes through several stages before a “record of decision” is finalized. Right now, the Pebble EIS is only at the scoping level. If you’re unfamiliar with the EIS process, public scoping is basically a brainstorming step. It’s the public’s opportunity to help define the breadth of the EIS to the lead agency, which in this case is the Army Corps of Engineers. (Read more about the scoping process.) During public scoping, if people don’t express concerns for the ecosystem-wide impacts of Pebble Mine and its infrastructure then the Corps’ EIS will not address them. Therefore, we must comment during the scoping period and demand that the alternatives in the EIS address the mine’s full environmental impact—which will sprawl across southwest Alaska and threaten the last great sockeye salmon run in North America.

The Bristol Bay area is exceptionally special and unique. Its landscape remains largely undeveloped and un-engineered. The major factors that decimated salmon elsewhere—habitat loss, dams, and pollution—are absent and salmon runs reach tens of millions of fish annually. Bristol Bay is where we can imagine the richness of fish that used to flood into the Columbia River or New England. It remains home to one of the most valuable and sustainable fisheries on Earth, one of the few remaining places where the full potential of the ecosystem is realized.

salmon jumping at waterfall

Salmon fishing boats in Naknek

Salmon fishing boats sit idle on a late winter day in Naknek, Alaska. The 2017 Bristol Bay salmon harvest was worth $670 million.

The Pebble EIS must address the mine’s potential, worst-case scenario effects on Bristol Bay’s salmon. A failure to contain the mine’s toxic tailings and wastewater would directly impact two of Earth’s most productive salmon producing watersheds. (The Kvichak River watershed, where part of the mine will be located, is home to the single largest salmon run in the world.) It must address potential groundwater exchange in the abandoned open pit, and whether the mining company can eliminate the risk of acid mine drainage. It must address whether the embankments for tailings ponds can withstand high magnitude earthquakes. It must address whether it’s even appropriate to build a mine whose wastewater will need to be treated indefinitely. It also must critically evaluate the mine’s supporting infrastructure, as it will potentially disrupt the world’s largest seasonal congregation of brown bears.

Map outlining Nushagak and Kvichak watersheds. Red star marks location of Pebble Mine.

Pebble Mine will straddle the divide between the Nushagak and Kvichak watersheds, two of Bristol Bay’s riches salmon producing areas.

By law, the EIS process must identify the least environmentally damaging practicable alternative. Common sense implies the least damaging alternative in this case is no mine at all, but the National Environmental Policy Act does not require agencies implement it. If we don’t demand the Corps critically evaluate the myriad impacts from the mine, then the Corps will merely focus on holes in the ground, “alternatives” of natural gas versus diesel to power the mine, how wide the service roads will be, and the size of the ports. The scope of the EIS will be so narrow to be useless for the protection of salmon. (For an idea of what this might be, look no further than the Donlin Mine Final EIS, whose purpose and need is: “produce gold from ore reserves from the Donlin deposit using mining processes, infrastructure, logistics, and energy supplies that are economical and feasible for application in remote western Alaska. The applicant’s stated need for the project is to provide economic benefits to Donlin Gold, Calista, and TKC shareholders; and to produce gold to meet worldwide demand.”)

I recognize a sad irony—or hypocrisy, if you prefer—of using a computer, which contains gold and copper, to type this post. I understand there’s a hole in the Earth, perhaps filled now with toxic water, where the metals in my machine were once trapped in rock. If you, like me, think Pebble Mine is irresponsible, then voice your opposition not only through the EIS process and with your votes at the ballot box (politicians who support Pebble Mine will not receive my vote), but also by reducing your consumption of products that use gold and copper. We, as consumers, need to say enough is enough. Our addiction to ever-higher levels of consumption brought us here. It’s not really sufficient to say “I’m opposed to Pebble Mine” then go out and buy the newest iPhone even though your old phone works just fine.

Everything we use, everything we make, has a cost. We’re at a point in history when surging human population growth and mass consumption are pushing ecosystems and species to their breaking point, creating an ecologically impoverished planet. In New England, wild Atlantic salmon are nearly extinct, and on the U.S. west coast only a tiny fraction of Pacific salmon return compared to historic levels. Don’t kid yourself: This sad story can repeat itself in Alaska.

We lose salmon one impassible culvert, one dam, one levee, one mine at a time, leaving us to suddenly wonder, where did all the fish go? In Bristol Bay we have a chance, maybe our last chance, to save large runs of wild salmon. If the mine is built and its proposed safeguards fail, we risk losing a significant portion one of the world’s last great sustainable fisheries. Future generations won’t be celebrating our decision if we develop this mine. They’ll criticize us for not learning from the mistakes of the past. Are we really willing to let hyper-consumerism and the promise of short-term profits potentially destroy the last great salmon run?

It looks like we’re on track to do so, unless enough people step up and say no.

Through June 29, 2018, you can submit scoping comments on the Pebble Mine EIS. I’ll share my scoping comments in a forthcoming post when they are finished.

Update May 23, 2018: My scoping comments can be found here.

Hibernation Hangover

In Glacier National Park, Montana, a black bear has emerged from hibernation, but hasn’t left his tree cavity den.

According to the park website, this bear was first seen on March 23. Since then, the black bear, who is male, has mostly rested in the tree cavity. After a long winter of hibernation, you might assume a bear would be eager to get moving and find something to eat, but bears often don’t leave their denning site for days, sometimes weeks, after they emerge in the spring.

A bear fresh out of the den isn’t the same bear it will be in May. Immediately after emerging from their dens, bears are active but neither hungry nor particularly thirsty. In one of the first studies on the physiology of hibernating bears, researchers found captive bears ignored food and water for up to two weeks and some bears didn’t begin to eat and drink normally for three weeks after they emerged from their dens. One grizzly bear didn’t even urinate for two days after it emerged. (In contrast, during another study a black bear in the fall urinated copiously, producing eight to sixteen liters of urine per day.)

This annual life stage of springtime bears has been described as “walking hibernation.” Compared to summer and, especially, early fall, bears in walking hibernation are hypophagic. They actively ignore food and drink little water while still surviving on body fat. During walking hibernation, bears experience an internal transition from full hibernation to a more active physiology. Research on brown bears in Sweden, which I wrote about previously, has found the body temperature and metabolic rate of brown bears doesn’t stabiliz until 10 and 15 days, respectively, after den emergence and their heart rate doesn’t stabilize for another month.

Graph that shows the timing of several variables affecting the start and end of hibernation in bears.

These graphs chart the relationship between physiological parameters of brown bears in Sweden. Den entry (left column) and exit (right column) are indicated by time zero (the green vertical line) to determine the sequence of physiological events. SDANN is the standard deviation of heart rate variability over five minute intervals. It was used a proxy measure of metabolic activity. A red line denotes when a variable was decreasing, while a blue line indicates when a variable was increasing, with the number of days from the entry/exit indicated. From Drivers of Hibernation in the Brown Bear and reposted under the Creative Commons Attribution 4.0
International License.

bear feet sticking out of hole in tree trunk

The transition from hibernation to fully active includes lots of resting. Screen shots from the Glacier National Park bear den live stream.

black bear in tree cavity

Possibly because their metabolism and heart rate remain somewhat low, many bears seem to loathe leave their dens, at least right away. So, it’s not uncommon for bears to remain near their denning site while their bodies transition back to more active levels.

The bear at Glacier will leave its tree cavity den relatively soon. His hunger will grow as his metabolism returns to active levels. His libido will increase too, and he’ll begin to prowl the land for females in estrous (the mating season for black and grizzly bears peaks in late spring). Compared to other stages in their annual cycle, less is known about the first few weeks of life for bears after they emergence from hibernation. It is rare for us to witness a bear’s life at this time. With webcams and other digital tools like GPS collars, we’re gaining a greater depth of knowledge about many wild animals. Glacier’s webcam provides a rare opportunity to observe a bear shortly after it has emerged from hibernation. Like most bears right now, it remains in a bit of a hibernative hangover.

The Difference Between Brown and Grizzly Bears

For my book on Brooks River’s bears and salmon, I find myself digging deep into natural history and ecology of brown bears. Sometimes I uncover research that challenges my long held assumptions. Take the difference between brown and grizzly bears, for example; something I often said was mostly based on geography and diet. As I wrote for Katmai’s website:

All grizzly bears are brown bears , but not all brown bears are grizzly bears. Grizzly bears and brown bears are the same species (Ursus arctos), but grizzly bears are currently considered to be a separate subspecies (U. a. horribilis). Due to a few morphological differences, Kodiak bears are also considered to be a distinct subspecies of brown bear (U. a. middendorffi), but are very similar to Katmai’s brown bears in diet and habits.

Even though grizzlies are considered to be a subspecies of brown bear, the difference between a grizzly bear and a brown bear is fairly arbitrary. In North America, brown bears are generally considered to be those of the species that have access to coastal food resources like salmon. Grizzly bears live further inland and typically do not have access to marine-derived food resources.

These geographic and dietary distinctions seem simple enough. However, there is little scientific evidence to support it. Both brown bears and grizzly bears exist, but the differences between them aren’t what I had long assumed.

bear grazing on vegetation with travertine and forest in background

A grizzly bear grazes on springtime vegetation near Old Faithful in Yellowstone National Park.

bear in water

A brown bear at Brooks Falls in Katmai National Park. (NPS Photo)

Although North American brown, grizzly, and Kodiak bears belong to the same species, Ursus arctos, bear taxonomy underwent many revisions before scientists reached this conclusion. In the nineteenth and twentieth centuries, taxonomists frequently lumped and split brown/grizzly bears into many different species and subspecies. The separation peaked in 1918 with the publication of C. Hart Merriam’s Review of the Grizzly and Big Brown Bears of North America in which Merriam proposed around 80 (not a typo) species and subspecies of North American brown bears. Taxonomists like Merriam relied on morphological characteristics that could be seen or observed to classify living and extinct organisms. Warm-blooded animals that have hair, breathe air, and produce milk for their offspring are mammals, but warm-blooded and air-breathing animals that lay eggs, have feathers and toothless beaks are birds. These are greatly simplified examples, I realize, and such tidy and clear distinctions aren’t necessarily common in nature. They often become more difficult to resolve at the genetic and species level, especially in cases of hybridization or when taxonomic distinctiveness is based on subtle physical differences.

Merriam’s nuanced classifications of brown and grizzly bears were based on differences in skull morphology and dentition, characteristics he examined painstaking detail. Among taxonomists, Merriam was a splitter. On southeast Alaska’s Admiralty Island alone, he classified five distinct species . In the Katmai region, Merriam described two species, Ursus gyas for the Alaska Peninsula and Ursus middendorffi for Kodiak Island , as well as others for bears living in the Cook Inlet area and on the Kenai Peninsula.

If you think his classifications of brown/grizzly bears was a little over the top, you’re not alone. Merriam foreshadowed opposition to his conclusions when he wrote in his Review, “The number of species here given will appear to many as preposterous . To all such I extend a cordial invitation to . . . see for themselves.” And they did. Most of the species or subspecies described by Merriam were later regarded as local variations or individual variants. While all of Merriam’s species have since been lumped together as U. arctos, in the mid 1980s as many as nine extant or extinct subspecies of U. arctos were recognized in North America , but the only names for North American brown bear subspecies in still widely used are U. a. horribilis, the grizzly bear, and U. a. middendorffi, the Kodiak bear. Recently, however, even these classifications have come under question.

In hindsight, it’s easy to scoff at Merriam’s conclusions. Could there really be dozens of brown bear species in North America? Within the methodologies and knowledge of his era, his results aren’t that far fetched. Little was known about the behavior, growth rates, ecology, and population dynamics of North American bears in the nineteenth and early twentieth centuries. Given access to the same tools and information as modern taxonomists, Merriam may have discovered grizzly and brown bears can’t be so easily divided by differences in skull and tooth shape.

Ursus arctos is one of the most widely distributed mammal species on Earth. Historically, brown bears were found from the British Isles south to North Africa and east across northern and central Asia to Alaska and most of western and central North America. Two to three million years ago, they split from a common ancestor shared with black bears . The oldest brown bear fossils are from China and date to about 500,000 years ago. By 250,000 years ago, they spread to Europe. During the last 100,000 years of the Pleistocene, bears immigrated and emigrated across much of the northern hemisphere as climate and habitat dictated. When continental ice sheets advanced, available habitat shrunk and bears became isolated into separate populations. When the ice receded, bears dispersed into the new territory. Beginning around 70,000 years ago, the first brown bears moved into North America. While we know when and where bears lived and live from fossils and historical records, this doesn’t necessarily deduce the genetic relatedness of modern populations.

Phylogeography is a branch of phylogeny, the evolution of an organism or group of related species or populations. As such, phylogeography traces the distribution of genetic variation through time and space. In this regard, mitochondrial DNA (mtDNA) is especially useful to track female ancestry. MtDNA  resides in the mitochondrion, a cell’s powerhouse, and is inherited from the mother only, unlike nuclear DNA which is a recombination of genes from both parents. According to mtDNA analysis, there is no divide between brown and grizzly bears based on an animal’s relationship to the coast or marine food sources, nor does it support the status of U. a. horribilis or U. a. middendorffi or any other historical subspecies in North America. The only historic classification that holds is at the species level—Ursus arctos. Instead, matrilineal ancestry suggests brown bears in North America fall into three main clades.

  • Mainland Alaska, Kodiak Archipelago, and northwest Canada.
  • ABC Islands (Admiralty, Baranof, and Chichagof) in southeast Alaska.
  • Southwestern Canada (Alberta, British Columbia) and the lower 48 States.

Clades are groups of organisms evolved from a common ancestor and consequently share a genetic relationship. The three North American clades, as well as others in Europe and Asia, are believed to be descended from brown bears living in isolated populations in Asia during the late Pleistocene . Since then, the mtDNA has remained geographically separated due to the tendency of female brown bears to be homebodies. Female brown bears are philopatric. They tend to remain near or have partly overlapping home ranges with their mother and do not rapidly invade areas already occupied by other brown bears . This can prevent or at least greatly slow mtDNA from mixing into other bear populations, even long after significant barriers like ice sheets have disappeared.

screen capture of Earth with clades of bears outlined.

Approximate range of brown bear clades in North America based on mtDNA. Different clades are represented by horizontal and vertical lines. The solid red circle marks the location of brown bears on the ABC islands.

Bears on the ABC Islands are the most genetically distinct of all Ursus arctos. Their mtDNA aligns them more closely to polar bears than to other brown bears , a genetic uniqueness most likely resulting from interbreeding with a small number of isolated polar bears at the end of the last ice age. Since then, female brown bears on the islands have not spread their polar bear genes to the mainland. Bears in British Columbia, Alberta, and into the lower 48 represent another lineage who arrived in Alaska around the same time as the ancestors of the ABC bears. During a warm interglacial period, some of these bears moved south into the mid continent before the ice advanced again and sealed them off from their brethren to the north.

All other brown bears in northwest Canada and Alaska, including those on Kodiak, belong to a clade that dispersed from Asia in two separate waves. Those in northwest Canada arrived first, perhaps as early as 33,000 years ago. Bears now occupying mainland Alaska represent the last pulse of ursine migrants onto the continent, arriving just before rising sea levels flooded the Bering Strait and closed the land bridge between Asia and North America. Excluding the ABC islands, all Alaskan brown bears belong to this pedigree, which stretches from northwestern Canada and Alaska west across Russia and into Europe and includes most of the world’s brown bears.

The results from mtDNA only convey information about the maternal line, however. MtDNA cannot trace genes spread exclusively by male brown bears, so it underrepresents the role of males in gene flow. Male brown bears have larger home ranges and disperse away from their mother’s home range more readily than females, especially during their first few years of independence. Males do carry one important bit of DNA that females don’t—the Y chromosome. Like mtDNA, it is only inherited from one parent, but unlike mtDNA it can only be passed from father to son, making the Y chromosome an important marker to trace paternal gene flow and diversity.

While mtDNA shows particularly strong clade differentiation  across the entire range of Ursus arctos, geographic variation in the Y chromosome of brown bears is much shallower . According to analysis of the Y chromosome, no deep genetic or geographical divergences could be found from bears in Eurasia or North America. Brown bears on the ABC islands and mainland Alaska, for example, share closely related haplotypes (a group of genes inherited from a single parent ) found in the Y chromosome. Even brown bears from populations as separate as Norway and the ABC islands have been reported to carry highly similar Y chromosomes . Male genes, therefore, flow across clades.

infographic showing hypothetical inheritance of mitochondrial DNA and Y-chromosome through three generations of bears.

Within mammals, mitochondrial DNA can only be inherited through the maternal line. The Y chromosome is only passed from father to son. MtDNA tends to stay within genetically related clades because female bears are philopatric. Male bears, due to their inclination to disperse farther and have larger home ranges than females, can spread Y chromosomes over bigger areas. Unlike nuclear DNA, neither mtDNA nor the Y chromosome are a mix of maternal and paternal genes.

This isn’t to imply male bears from the Yukon immigrate to Europe or vice versa, just that males are more apt to wander and set up home ranges well away from their mother. If female brown bears, due to their philopatry, differentiate a population’s genetics over time, then male bears homogenize it. In other words, female brown bears like to stay in familiar terrain, but males often spread their seed far and wide.

With evidence of geographically isolated clades through mtDNA but not in the Y chromosome—can we still divide brown bears into biologically significant units? Even though genetic research adds another dimension to our understanding of wildlife, morphology remains an important way to differentiate species, and subspecies don’t necessarily need to be from separate or unique ancestry to be worth protecting. Grizzly and brown bears still exist, just not along a clean geographic and dietary divide. Where we draw the line is less important than the overall conservation of bears. Populations of brown bears—whether they are from Katmai, Kodiak, or Yellowstone—remain ecologically and culturally special no matter their genetic distinctiveness. Bears in Yellowstone are geographically and (at least currently) genetically separated from other “grizzlies.” Kodiak bears aren’t genetically distinct enough to justify them as a separate clade even though they have been isolated from mainland bears for approximately 12,000 years. Hypothetically speaking, if bears are extirpated from Kodiak or Yellowstone then they won’t be coming back and a valuable repository of genetic diversity will be lost forever.

The line between a brown bear and a grizzly, as I used to define it, was always tenuous at best. (Should grizzlies in interior Washington, British Columbia, and Idaho—who may have fed on salmon before runs in the Columbia and Snake watersheds collapsed—be considered brown bears?) Now through DNA analysis we know Ursus arctos cannot be so arbitrarily split based on their geographical closeness to the ocean. It’s still ok to say grizzly, Kodiak, or brown bear—the names can still be incredibly powerful and useful—but maybe the only truly accurate name for them is Ursus arctos.

References:

Bidon, T. , et al. Brown and polar bear Y chromosomes reveal extensive male-biased gene flow within brother lineages. Mol. Biol. Evol. 2014. 31(6): 1353-1363.

Davidson, J., et al. Late-Quaternary biogeographic scenarios for the brown bear (Ursus arctos), a wild mammal model species. Quaternary Science Reviews. 2011. 30:418-430.

Rausch, R. L. Geographic Variation in size in North American brown bears, Ursus arctos L., as indicated by condylobasal length. Canadian Journal of Zoology. 1963. 41(1): 33-45.

Schwartz, C.C. et al. “Grizzly Bear,” in Wild Mammals of North America: Biology, Management, and Conservation. 2nd Edition. Editors Feldhamer, George A., Bruce C. Thompson, and Joseph A. Chapman. John Hopkins University Press. 2003.

Talbot S. L., et al. Genetic characterization of brown bears on the Kodiak Archipelago. Final Report to Kodiak National Wildife Refuge, U.S. Fish and Wildlife Service. 2006.

Waits L. P., et al. “Genetics of the bears of the world.” In Bears: Status Survey and Conservation Action Plan. Compiled by Christopher Servheen, Stephen Herrero, and Bernard Peyton. IUCN/SSC. 1999.

Waits, L. P., et al. Mitochondrial DNA Phylogeography of the North American Brown Bear and Implications for Conservation. Conservation Biology. 1998. 12(2): 408-417.

 

To Change or Not To Change: A National Park Question

Last year, Isle Royale National Park released a draft plan to determine whether and how to stabilize the park’s wolf population. After evaluating the merits of several alternatives, weeding through public feedback, and with only two wolves remaining, the park has decided to introduce 20-30 wolves over a three-year period. In the park’s decision, managers have affirmed their belief that wolves on Isle Royale are an irreplaceable part of the ecosystem, and their loss is unacceptable.

Parks are being increasingly managed for change, but the myth of national parks as static vignettes of primitive America remains pervasive. As I wrote on this issue last year, parks are not pure. We live in an era of unprecedented change, and situations like Isle Royale’s will only become more common.

The National Park Service has made strides toward acknowledging that parks will change, but it’s time to put a greater effort into planning for it. To help the public better understand the dynamic nature of national parks and their significance—what we’re willing to save and what we’re willing to let go—there should be an effort across the NPS to identify at-risk resources and decide whether to protect them. Resources to protect would be species, habitats, and processes that if lost would impair the significance of the park or reduce biodiversity. This could help guide current and future management of parks, leading the NPS to implement preventative or prescriptive actions to stave off unacceptable impairment instead of waiting until it’s nearly too late.

In areas with endemic or endangered species—such as Hawaii Volcanoes, Haleakala, and Channel Islands—it may be most appropriate to manage against change to mitigate the risk of losing unique habitats or species to extinction.

In other areas where forest compositions will shift, it may be more appropriate to let change happen as long as native biodiversity is protected.

view of tundra and shrubs with mountains and lake in background

In Katmai National Park, shrubs and trees now grow at higher elevations compared to 100 years ago.

view of mountain scenery with craggy peaks and snowfields.

Should this view be protected or should tree be allowed to encroach on the scene? At North Cascades National Park, tree line is expected to rise in elevation which may threaten views like this one near Cascade Pass. Forests in this park, especially at low elevations, are also projected to burn more frequently under a warmer climate.

Importantly, this planning effort could help the public better understand decisions like Isle Royale’s, which seems inconsistent and arbitrary to many people who commented on the plan.

Biologists predict wolves will be extirpated from Isle Royale within a few years without direct intervention, but why intervene on the behalf of wolves at all? Wolves, as a species, don’t need Isle Royale to survive. As the NPS reasons, it’s less for them, and more for the park. Without wolves climate change would have a greater influence on the archipelago. Plant communities would shift dramatically under heavy browsing pressure from moose, causing a cascade of effects and perhaps, according the park’s Final Environmental Impact Statement, become less resilient.

“Under alternative A, increased [moose browsing] is probable and combined with climate change effects, it is likely that the rate of vegetation changes would be exacerbated and potentially accelerated. Additionally, it is expected that the resiliency of current wildlife populations to change would be reduced and contribute to more rapid population swings. Under alternative B [the preferred alternative] and C, it is expected that the project [sic] warming trends influences [sic] on the island would be less likely to be compounded by herbivory and its associated impacts.” (Pg. V)

Scenarios like Isle Royale’s will only become more common as we continue to fragment habitat, introduce invasive species, and change the climate. Not that I want it to be this way. Ideally park ecosystems would remain healthy enough and function normally enough so native species and biodiversity are protected without our heavy-handedness, but unless we shift our priorities dramatically then we’ll find ourselves stepping in at ever increasing rates.

We can no longer afford to think of parks as museums. What exists in them exists because we, directly or indirectly, choose it. In the face of unprecedented change, national parks cannot remain static. It wasn’t feasible in the past and it’s increasingly infeasible now. Where do we draw the line and how do we intervene? That’s something we need to decide right now—nationwide, collectively, and not in a piecemeal manner.

 

Northern Elephant Seals

Northern elephant seals are one of the largest pinnipeds on Earth. Large males can weigh as much as an SUV—four to five thousand pounds. Females are much smaller, topping off at only about one thousand pounds. Since the first few pairs began to haul out at Point Reyes in the 1970s, more and more have arrived each year.

seal resting on cobble beach, dock and boathouse in background

A subadult male elephant seal rests on a cobble beach in the Chimney Rock area at Point Reyes National Seashore.

This aggregation is a seasonal event. Unlike many mammals, the birthing and breeding season coincide in elephant seals. Males arrive first, establishing beach front territory where they’ll be able to establish and protect a harem. Pregnant females show up next, after which they soon give birth. Pups are weaned after about a month of nursing. Like bears, female elephant seals fast while giving birth and nursing. They do not eat, drink, or leave the beach during this time. Consequently, they lose 30-40% of their body weight during this short time. Mating occurs before the females depart to the open ocean. Adult males stick around longer, aiming to increase their chances of mating with as many females as possible.

Males have unique individual calls, and helps them recognize each other and avoid some physical conflict. While my mid January visit was too brief and my viewing was too far away to make such differentiations, there was plenty of activity to see and hear.

The biggest bulls already had established territories and harems. Newborn pups cried nearly constantly, especially when a wave of cold water washed over them. Females barked at each other too. For gregarious creatures, they sure let others hear it when their personal space is encroached upon.

(This place could really benefit from a webcam.)

The main overlook provided the best viewing opportunity to see bulls with harems. The females didn’t seem to be ready to mate, having just given birth or just about to, but that didn’t stop some of the bulls from trying. Forced copulation is not uncommon among elephant seals. Females can be seriously injured and pups crushed by randy males.

I also found good viewing opportunities nearby at the old U.S. Life Saving Station.

elephant seal resting on side with penis emerging

I had no idea what was going on here, but later learned this is an elephant seal’s penis. (Also, I’m told, these are nicknamed a “pink floyd.”)

Northern elephant seals were once thought to be extinct from decades of unrelenting and unregulated hunting, then a small population was found off of the Mexican coast in the early twentieth century. Luckily, the species was given strict protection while their ocean habitat remained largely intact, and their population has grown about six percent per year since the early twentieth century. There are now probably more than 150,000 northern elephant seals.

Many marine mammal species were once so rare that we can’t take them for granted, and we need to ensure their habitat and food sources are protected. If you’re in the neighborhood of Point Reyes National Seashore in January and February, you must stop and see elephant seals at Chimney Rock.

Drivers of Hibernation

Brown and black bears hibernate to avoid winter famine. For five to seven months, they do not eat, drink, urinate, or defecate, a strategy quite unlike other mammalian hibernators. Chipmunks, for example, cache food to eat in between bouts of torpor. Marmots and arctic ground squirrels don’t eat during winter and survive off of their fat stores like bears, but they activate their metabolism periodically to wake and urinate.

I recently spent about 40 hours reviewing studies related to hibernation and denning in brown bears for a chapter in my book on Brooks River’s bears and salmon, which reminded me just how remarkable this process is. While in the den, bears spend about 98% of their time not moving. Their heart rate declines dramatically from 50-60 beats per minute during summer to 10-20 per minute in hibernation. During this time, they hardly breathe, taking 1.5 breaths per minute on average. Their body temperature drops several degrees entering them into a state of hypothermia. Finally, the metabolic rate of a hibernating bear is 70-75% less than its summer peak. To survive, bears subsist on their body fat, catabolizing it into energy and water.

brown bear sitting on rock surrounded by water

All brown bears, like this adult male known as 89 Backpack, get fat to survive.

Despite their lack of physical activity, hibernating bears maintain muscle strength and bone health. Even if immobilization didn’t cause starvation, osteoporosis, and atrophy in people, we would die of dehydration if placed in an equivalent situation. Hibernating bears, however, are nearly completely self-supporting. The only input they need from the outside world during hibernation is oxygen.

The physiology of bear hibernation is complicated and not fully understood. Scientists are still elucidating basic details about this remarkable process. For example, what causes bears to enter and exit the den? How long do bears need to switch their metabolism from to hibernating mode? As it turns out, the switch is a long process.

Researchers in Sweden used implanted heart rate monitors and GPS-enabled tracking collars on fourteen brown bears. The devices recorded the movement, heart rate, heart rate variability, and body temperature as well as ambient temperature and snow depth. The results, published last year in “Drivers of hibernation in the brown bear,” are insightful because it allowed the researchers to develop correlations between the variables that drive and trigger hibernation.

In fall, well before hibernation begins, body temperature and heart rate of bears began to decrease. Heart rate started to slow, on average, 24 days before den entry, and body temperature began to drop 13 days before den entry. Overall activity lessened 25 days before entry, but metabolic activity declined steeply just as the bears entered their dens. It took an additional 20 days after for heart rate and metabolic activity to bottom out.

The transition back to a more active physiology started long before bears left their dens. Heart and metabolic rate began to rise one month and 20 days, respectively, before den exit. Body temperature began to rise even earlier, a full two months before den exit when winter still locked the landscape in ice and snow. All bears left the den when their body temperature was 36.7˚C (98˚F) ± 0.15 °C, the active-state body temperature for brown bears. As the researchers note, the narrow temperature range at this time suggests bears exit the den when their body temperature reaches a specific point. Body temperature and metabolic rate stabilized 10 and 15 days, respectively, after den exit, but heart rate didn’t stabilize for another month.

Graph that shows the timing of several variables affecting the start and end of hibernation in bears.

These graphs chart the relationship between physiological parameters of brown bears in Sweden. Den entry (left column) and exit (right column) are indicated by time zero (the green vertical line) to determine the sequence of physiological events. SDANN is the standard deviation of heart rate variability over five minute intervals. It was used a proxy measure of metabolic activity. A red line denotes when a variable was decreasing, while a blue line indicates when a variable was increasing, with the number of days from the entry/exit indicated. From Drivers of Hibernation in the Brown Bear and reposted under the Creative Commons Attribution 4.0
International License.

Even though the bears’ physiology initiates the ultimate beginning and end of hibernation, climate plays a role in this process too. Changes to body temperature before den entry were affected by ambient air temperature, but bears largely relied upon a physiologic slowdown to cool themselves. In spring, bears left the den when the weather was right, exiting when air temperature rose to above 3.7˚C ± 1.5 ˚C (38.7˚F ± 2.7˚F).  Some biologists have suggested that food availability drives the timing of den entry, but this study did not attempt to test the hypothesis.

As a survival strategy, bear hibernation is remarkably efficient, and no other animal attains the same physiologic feats. Small mammal hibernators wake to pee; bears don’t even need to do that. Changing from an active metabolism to one of hibernation and back again takes a lot of time. If you are fortunate enough to see a bear in the middle of fall or the middle of spring, that bear is likely living in a transitional body equipped to handle two worlds—one with food and one without.

 

Filling the Gaps

Last July on bearcam, we witnessed the ascent of 32 Chunk in the hierarchy at Brooks Falls. Chunk was the largest bear to consistently use the falls in July, and most bears didn’t challenge him. We watched Chunk interact with many bears, occasionally with some that I (and many bearcam watchers) didn’t recognize. In mid July, for example, we saw Chunk displace another large adult male.

GIF of bear on left moving away from approaching bear who appears at right.

In this GIF from July 2017, a unidentified bear avoids the approach of 32 Chunk.

At the time, a few bearcam watchers speculated the subordinate bear may have been 856, who was the most dominant bear at Brooks River for many years. As I wrote in a previous post, I didn’t think this was 856. So who was it? Was he a previously identified bear or a newcomer to the river?

Before his seasonal position ended this fall, Ranger Dave from Katmai posted photos of several bears who were seen along the river, but were unknown or unrecognized by webcam viewers. Assuming Ranger Dave’s IDs are correct, which they are much more often than not, the unknown bear in the GIF above could be #611.

brown bear standing in water

Bear 611 at Brooks Falls in 2017. Photo courtesy of Dave Kopshever and Katmai National Park.

611 is a bear I don’t know much about. According to my notes, he was first identified in 2015, but only in September and October not in July. Preliminary bear monitoring data from that fall state this bear was an older subadult or young adult at the time.

611_09162015

611 in September 2015, the first year he was identified. NPS photo.

I may be splitting hairs or misunderstanding Dave’s intent, but note that Ranger Dave said, “This is believed to be 611” when he posted the photo. Perhaps there’s still some uncertainty regarding the ID. Filling in the gaps of who’s who at Brooks River can be difficult, and it isn’t possible to identify every bear with certainty. But—based on scars, size, head shape, and ear color—I am fairly convinced the bear in the 2017 photo posted by Ranger Dave is the same bear that Chunk displaced in the GIF above.

At Brooks River, I made the effort to learn to recognize the bears who used the river frequently. Since bear behavior is often complex and can vary from animal to animal, recognizing individual bears leads to a better understanding of their growth, behavior, and strategies for survival. If 611 returns in 2018, we’ll have another opportunity to observe his behavior. Will he challenge other adult males for fishing spots or will he avoid confrontation more often than not? Whatever happens, it will allow us to learn just a little more about the bear world.

Hey National Parks: You Need More Webcams

Katmai National Park and Preserve is a place of unparalleled resources. It’s studded with over a dozen active volcanoes and protects the site of the largest volcanic eruption of the twentieth century. Its lakes and rivers are swarmed annually by millions of salmon. Abundant food and an undeveloped landscape provides habitat for over 2,000 brown bears, more than any other national park. For 9,000 years people have made it their home, adapting to the landscape’s constant change and challenges.

pumice covered landscape with volcano in background

Mount Griggs towers behind Baked Mountain in the Valley of Ten Thousand Smokes.

As a park, it’s very remote and expensive to experience. Its coastline, measuring over 400 miles, and almost all of the rest of the 4.1 million-acre park remain roadless. For nearly a century after its establishment, Katmai was only accessible to people who could afford to visit and were physically capable of doing so. Webcams (bearcams) changed that.

Webcams allowed Katmai National Park to democratize itself, providing audiences all over the world with meaningful opportunities to connect with the park, especially its bears, and build stewards on a global scale. Survey results* indicate watching the bearcams increased viewer interest in Katmai and wildlife conservation, and viewers’ interest in national parks and wildlife conservation is on par with on-site visitors. Essentially, webcams can inspire stewardship on the same level as a physical visit to a park. They are powerful interpretive tools with great potential to increase awareness, understanding, and stewardship of wildlife and conservation areas. Yet, national parks rarely utilize webcams to their full potential and online audiences are either ignored or deemed secondary to on-site visitors. This needs to change.

bear sitting on rock in river

Bear 708 Amelia sits on a rock–a typical scene on Katmai’s webcams.

Inspired by the success of Katmai’s webcams and to communicate the need to utilize them in more places, I’ll be leading a session at the 2017 National Association of Interpretation Conference. Roy Wood, Katmai’s former Chief of Interpretation and the current Chief of Interpretation and Education at Shenandoah National Park, and Ryan Sharp, Assistant Professor of Park Management and Conservation at Kansas State University will join me. Roy and I will discuss our methods to interpret bears, salmon, and other park resources to online audiences. Ryan will present survey results exploring the online bear viewing experience at Katmai and its influence on support for bear conservation and management.

screen shot of description of conference presentation

If you’re interested in watching but can’t  attend, don’t worry. A presentation about Katmai’s bearcams wouldn’t be complete if it wasn’t streamed live on bearcam. That’s why I made tentative plans with explore.org, who hosts and funds Katmai’s webcams, to live stream the presentation. The session begins at 10:45 a.m. PT on November 16.

In the age of internet and social media, traditional interpretive programs catering solely to on-site visitors (through guided walks, ranger-led talks, slide shows, etc.) are no longer adequate to build and maintain widespread stewardship for parks and other conservation areas. When I worked at Katmai National Park, I was amazed, awestruck really, at the reach and effectiveness of the bearcams. Nearly everyday, I could find evidence of people connecting in meaningful ways with Katmai’s wildlife. Katmai is better protected today than it was even ten years ago due to the awareness and understanding its webcams have brought to people around the world.

The bearcams annually reach tens of millions of people worldwide. With effective interpretation, webcams consistently and positively engage viewers, increase public awareness and stewardship of wildlife, expand messaging to pre and post on-site visitors, and extend interpretive messages to audiences worldwide. Existing technology now provides conservation organizations with the ability to reach people all over the world, not just those who are fortunate enough to visit. We need more webcams and more rangers on them. This is how parks take their message to the world.

Update (Nov. 17, 2017): A replay of my presentation is now online.

Download the slide presentation in PowerPoint (199 MB) or Keynote (127 MB).

*Sharp, Ryan, J. Skibins, and J. Sharp. Online and onsite brown bear viewing: Influence on visitors’ support for conservation-based management at Katmai National Park and Preserve. Unpublished Report to Katmai National Park and Preserve. Kansas State University. Jan. 23, 2017.

Injured Nose Bears

It’s not uncommon to see bears with open wounds and distinctive scars, like bear 83 who seems to repeatedly get injured.

crescent-shaped wound on bear rump.

Photo of 83’s wound from 2015. In 2016, his rump was injured again courtesy of bear 747.

Wounds and the subsequent scars are useful when identifying Brooks River’s bears, since each bear carries a unique suite of them. 83 now sports a large scar on his rump.

Bear standing in white water.

The lump on 83’s rump marks the scar from his 2015 injury.

Sometimes though, we see bears with scars or injuries that may be more than superficial, perhaps impacting the sense they rely on most.

On September 13, 2017, a bear with a large, distinctive scar on his left shoulder was photographed at Brooks River.

1stnite2

Photo courtesy of Lee (aka RiverPA) via Flickr.

Most distinctively, his nose is split.

1stnite

Photo courtesy of Lee (aka RiverPA) via Flickr.

This appears to be an old injury and when I saw these photos I wondered have we seen this bear before?

In 2010 and 2011, a subadult bear with a torn nostril was seen at Brooks River. Bear 253 was a young subadult at the time, but Katmai’s bear monitor was not able to determine its sex. Its nose was most likely injured in 2010 as photos from 2011 show some healing.

 

 

253 probably isn’t the unidentified male photographed with the nose injury this past September though. 253’s muzzle is long and somewhat pointed while the male bear’s muzzle is blockier in shape. The nose injury on the male bear also seems more symmetrical than 253’s.

Would injuries like these impair these bears’ sense of smell? Perhaps, especially if it reduced the surface area inside the nose where scent can be detected.

Bears have a legendary sense of smell. The inside of their nose is filled with many turbinals, a complex scaffold of paper-thin bones. Humans have turbinal bones too, just far less than ursids. In black bears, for example, these bones greatly increase the surface area inside the nasal cavity, providing 100 times more nasal mucosa, or mucous membranes, than humans. More tangibly, if the area of muscous membranes inside the human nose equals the area of your typical postage stamp, then the area covered by mucous membranes inside the black bear nose covers an 8.5 x 11” sheet of office paper. On the surface of the membranes are millions and millions of scent detecting cells. In short, bears live in a world of odors we can scarcely imagine.

Like human eyesight, hearing, and smell, the strength of these senses likely varies in bears. Some bears may have worse eyesight than others (although it’s a myth that bears have poor eyesight; they don’t). Others may have worse hearing. In the case of bears with injured noses, they may not be able to smell as well as their cohorts. (It’s important to note that in the case of 253 and the adult male seen this past September, the injury to their nose may not be deep enough to affect the turbinals.)

If bears are anything though, they are tough survivalists. A nose injury could impose a severe disability on them, but that won’t stop them from doing whatever they need to do to survive.