Fat Bear Week 2019 Endorsement

Avoiding the news when your job is internet-based is like avoiding the flu when your entire household is infected. So, try as I might, I keep stumbling upon headlines about upcoming presidential primary elections. The big question on the minds of pundits seems to be, “Will people choose the candidate who best represents their values or the one who they think is most electable?”

As a certified bearcam aficionado and well-known Katmai National Park pundit, I am pleased to announce that I have do not have that issue, at least not for the upcoming “election” called Fat Bear Week. My candidate isn’t a compromise between values and electability. He’s the real deal, the one, the only, the titanic bear known as 747. He deserves your vote.

silhouette of fat bear sitting in river

Don’t you call me pudgy, portly, or stout. Just now tell me once again, who’s fat? (NPS photo of bear 747 by N. Boak)

Seven-four-seven is a giant among bears, an adult male in the prime of his life who uses his size to dominate access to his preferred fishing spots in the jacuzzi and the far pool. His experience and skill pay off each fall, supplying 747 with the substantial fat reserves necessary to survive winter hibernation without eating or drinking.

To get this fat, you need to catch and eat a lot of salmon. Adult brown bears on Kodiak Island consume can consume an incredible 6,146 pounds (2,788 kg) of salmon per bear per year! Given 747’s excellent fishing skills and ability to routinely access the most productive fishing locations at Brooks Falls, I have no doubt his salmon consumption is on par with the biggest Kodiak bears. Stuck in his own version of “feed”-back loop, 747 gets fatter and fatter until it’s time to enter the den. (And, no bears probably can’t get too fat.)

If you don’t believe me about 747’s qualifications, believe the Internet, always an impartial repository of truth and honesty. In 2017, I recorded a video of 747 in all his epic fatness. If anything can be gleaned from viewer comments (and of course we know that YouTube comments represent the highest form of public discourse), 747 is an extra THICC absolute unit who is ready to hibernate through two winters.

The people have spoken.

At Brooks Falls, 747 remains quite dominant and can often access any fishing spot he chooses, which is not surprising given his size. Adult males typically rank at the top of the bear hierarchy. Even so, 747 still faces competition, in real life and in Fat Bear Week. This summer, I was awestruck watching 747 clash with another adult male, 68, in an intense fight.

 

Sixty-eight emerged victorious in the battle, not only securing access to a preferred fishing spot at Brooks Falls but also assuring his dominance over 747. Bloodied from the fight, 747 left the falls area almost immediately and I thought I might not see him for the rest of the evening.

bear standing in water with some blood dripping from his lower lip

747 bleeds from the mouth after his fight with 68 on July 2, 2019.

Within an hour or so, he returned and began fishing like nothing happened. When you only have a few months to prepare for winter hibernation, there’s little time to waste.

Like so many things in life, 747’s Fat Bear Week victory is not guaranteed. My 2017 and 2018 endorsements for 747 were followed by his sound defeat. This year, his competition is just as fat if not fatter.

GIF of bear sitting upright and scratching an itch with her left front paw

Dear Holly,

Game on. See you in the Fat Bear Week finale!

Sincerely,
747’s Campaign Manager

Your Fat Bear Week vote can be based on any number of factors. You can consider a bear’s annual overall growth like that experienced by cubs and subadult bears. Perhaps you want to weight your vote toward bears with extenuating circumstances such as a mother’s cost of raising cubs or the additional challenges older bears face as they age. No matter what though, 747 once again offers you, the astute Fat Bear Week voter, the opportunity to support a bear who is both the fattest and the largest, two traits that are not mutually exclusive.

Complete your civic duty and vote for Brooks River’s fattest bear from October 2 – 8 on Katmai National Park and Preserve’s Facebook page. Look for the head-to-head Fat Bear Week matchups. The bear whose photo receives the most “likes” advances to the next round, until one bear is crowned fattest bear on Fat Bear Tuesday, October 8. Don’t forget to watch Katmai’s fattest bears every day on explore.org.

Fat Bear Week 2019 Bracket.jpg

Happy Birthday Bear

Across much of North America, tucked within isolated dens, a new generation of bears is beginning their lives.

Mother bears spent much of the last year preparing for this event. Although the timing varies among species and individuals, North America’s bears mate in late spring and early summer. The fertilized eggs, however, do not immediately implant in the uterus, undergoing only a few cell divisions before they enter a state of arrested development. During this process of delayed implantation, the female goes about her business while embryos remain in suspended animation. Implantation and fetal growth renew only close to the time she enters her winter den. Afterward, bear fetuses gestate for 6 – 8 weeks.

The gestation time is remarkably short for such a large mammal, and it produces especially tiny and helpless cubs. Brown bear cubs, for example, weigh a scant pound and measure only 8 – 9 inches long at birth, about the size of a beagle puppy. They are also born blind, lightly furred, and nearly immobile. Their ears are closed and their muzzles are short with a round, toothless mouth. Newborn cubs are so underdeveloped and small that they cannot maintain their own body heat in the den and must remain in contact with their mother to stay warm. About the only thing they can do is scream, which, not unlike human newborns, they employ frequently to gain their mother’s attention. It’s hard to imagine large adult bears so helpless, but they all start life this way.

Three small cubs held in a person's hands.

Newborn black bear cubs. U.S. Fish and Wildlife Service photo.

The small size of newborn cubs is surprising for animals that weigh several hundred pounds when fully grown. Generally, larger mammal species have longer gestation periods and give birth to larger offspring than smaller mammal species. African elephant calves gestate for nearly two years and are born bigger than elk calves; elk calves gestate for about eight months and are born bigger than deer fawns; deer fawns gestate for seven months and are born bigger than fox kits; etc. But, bears break the rule by a considerable margin. Bears give birth to the smallest offspring in comparison to adult female body size of any mammal.

Cubs are only 1/200th the size of even the smallest reproducing female grizzlies and commonly 1/500th or less for large adult brown and polar bears. In contrast, newborn human babies are an order of magnitude larger than bear cubs. A 10 pound child born from a 150 pound woman is 1/15th the size of its mother (yeah, I know that’s a big baby but the math was easy). Additionally, offspring born to large mammals are generally precocial, i.e. they are at least somewhat and sometimes highly mobile soon after birth. Bear cubs, however, are more akin to helpless hatchling birds or pinky mice. There is no parallel among placental mammals—only marsupials give birth to offspring as undersized as bears.

But why are bear cubs born purposefully premature? Why not just have a longer gestation time and birth larger, more independent cubs? The short gestation period and the relatively small size of bear cubs at birth both appear to be an adaptation to maximize the use of fat.

Bears are the only mammals that give birth while hibernating, a time when they do not eat, drink, urinate, or defecate. Survival during this time is dependent on stored body fat, but the paradigm poses a problem for expectant female bears. A developing mammal fetus cannot metabolize free-fatty acids, perhaps because these substances do not cross the placenta as readily as sugars and protein. So, as long as a bear tries to sustain fetal growth through her placenta, she needs to draw energy from her own body protein. Fetuses also produce bodily waste, which is transferred to the mother and adds to her physiological challenges. To cope, bears evolved an alternative strategy, one that allows her to give birth while hibernating, support the continued growth of cubs, and keep the family safe.

Unlike in the womb, baby mammals can metabolize fat shortly after birth and milk is the vector to deliver it. Bear milk is a particularly rich and nourishing substance. Brown bear milk, for example, is about 22% fat by volume. Polar bear milk is even richer, a whipping cream composed of over 30% fat. By shortening the gestation period, mother bears trade placental nourishment (mostly protein and sugar) for mammary nourishment (mostly fat) and tap into the one resource they have in abundance.

fat brown bear exiting water

Female bears utilize their fat reserves to support the growth and nourishment of their cubs.

On a diet of fatty milk, a brown bear cub can gain about a 1/5 of a pound of body mass per day, weighing about 5 pounds when one month old and 15 – 25 pounds by 90 days. Not coincidentally, this is about big as they would be if gestation was of an “expected” length like other placental mammals. The den, therefore, becomes a surrogate womb, protecting the family during the most vulnerable time in their lives.

Two polar bear cubs standing at the entrance to a snow den.

Polar bears play at the entrance to their mother’s den. These cubs are probably several weeks old. U.S. Fish and Wildlife Service photo.

Bears face many obstacles to survive and reproduce, not the least of which is winter famine. Hibernation provides bears with the ability to outwit winter by surviving on accumulated fat, but during this time a female bear must support the growth of her cubs with nothing more than the energy stored in her body. Given the challenges posed by gestation, hibernation, and winter famine, the birth of a bear represents a remarkable and unparalleled feat of mammalian adaptation.

So, happy birthday brown bear.

My Live Bearcam Broadcasts in 2018

This was a busy year on the bearcams, courtesy of explore.org and Katmai National Park. We hosted more live broadcasts this  year than any other year since the bearcams first went live in 2012.

During play-by-play broadcasts Katmai rangers and myself narrated the Brooks River’s wildlife activity, much like broadcasters for sporting event (although the lives of brown bears and salmon is no game). We never knew what might happen during a play-by-play. Watching the prolonged posturing between two of Brooks River’s largest adult males, 856 and 32 Chunk, on July 12 and integrating the ranger’s radio traffic into the September 17th broadcast are two of my favorite play-by-play moments.

The other broadcasts, live chats, typically focused on a specific topic such as bear fishing styles, hibernation, and bear research at Brooks River. Rangers Andrew LaValle and Russ Taylor from Katmai joined me as frequent co-hosts for live chats and I was also fortunate enough to speak with many special guests. Perhaps the most memorable moment from these broadcasts occurred when bear 132 and her spring cub almost stepped on Ranger Andrew and I during our Katmai centennial live chat on September 24.

If you enjoy these, then please watch many other broadcasts hosted by Katmai National Park rangers and staff on explore.org’s education channel on YouTube.

 

Stuff I wrote in 2018

I was busy on a keyboard this year, even though there were long gaps between posts on this site. In case you missed them, here are the posts that I wrote for explore.org in 2018. They are listed in the order they were posted. My personal favorites include “How does a bear family breakup,” “How many salmon will a bear eat,” “Bearcam live chat surprise,” and “Living with Bears in Churchill.”

  • Brooks River Bear Mating Season: In June, food isn’t the only thing on a bear’s mind.
  • 2018 Bearcam Stories: 503: Emancipated from his adopted mom in the spring of 2016, bear 503, also known as Cubadult, has quickly grown into an energetic and often playful young adult.
  • Early June at Brooks Falls:  Standing at the falls from early to mid June is an exercise in patience and an opportunity to reflect on the changes soon to come.
  • 2018 Bearcam Stories: The Elders of Brooks River: Their longevity of Brooks River’s oldest bears demonstrates a level of individual success few bears achieve.
  • The Mouth of Brooks River: The lower river cams provide expansive views, colorful sunrises and sunsets, as well as the opportunity to see many yearly and seasonal changes.
  • What to Look for 2018: The Bear Hierarchy: Watching the ebb and flow of the hierarchy allows us to at least partly understand the conflict and challenges faced by bears.
  • Bear 856: On Top Again: Bear 856 appears to be big enough and healthy enough to show the river’s other adult male bears he’s ready to compete once again.
  • Death of a Bear Cub at Brooks River: As the smallest and most vulnerable of all bears, first year cubs (also called spring cubs or cubs-of-the-year) face significant risks and challenges, not the least of which are larger bears.
  • Dumpling Mountain Hike: Rising over 2000 feet above Brooks River, Dumpling Mountain offers anyone a quick escape from the hustle and bustle of Brooks Camp. Each time I hike on it, I get an opportunity to see the land in a new way.
  • Four Cubs for 402 Again: No matter this family’s fate, we can marvel at 402’s determination to follow her maternal instincts in an attempt raise another generation of Brooks River’s bears.
  • How Does a Bear Family Breakup? Until somewhat recently, I stated that 402 had “abandoned” her yearling (now known as 503). While this might be true in a sense, I no longer think that this is an accurate way of describing the event. After reading more about the emancipation process, I’ve come to believe 402 didn’t abandon her yearling in 2014. She emancipated him.
  • How Many Salmon will a Bear Eat? We often observe bears partake in marathon fishing sessions at Brooks Falls, so how much can they eat in a day or season? Quite a lot.
  • Salmon on the Underwater Bearcam: The calmer, deeper water near the outlet of Brooks River provides salmon with a temporary refuge that is relatively safe and costs them little energy.
  • 451 and Her Yearlings: 451 is currently raising her second litter, and it’s easy to see that the family is skinner than many of the other bears on the bearcams.
  • Bearcam Line of Sight: Where are the bearcams and where, specifically, do they look?
  • Brooks Falls Trail: Simply walking to Brooks Falls can be an exciting and memorable experience and allows great opportunities to explore a changing habitat.
  • Mid Summer Change at Brooks River: Are fewer bears at Brooks River a sign of change?
  • An Exceptional August: Regarding bear activity at Brooks River, August 2018 has been exceptional.
  • Fishing By Snorkeling: Efficient and effective, snorkeling is one of the best strategies to scavenge fish.
  • Can a Bear be Too Fat? When you see bears whose stomachs appear to drag on the ground, one wonders if a bear can grow too fat for its own good.
  • Bearcam Live Chat Surprise: “This being a live broadcast it’s entirely possible…a bear could walk through the screen at any time. So if we have to exit or end the broadcast abruptly that’s probably why.”
  • Fat Bear Week Quarterfinal Preview: The competition just keeps getting bigger.
  • Mike Fitz’s Favorite Bearcam Moments of 2018: Here are a few of my favorite bear cam moments for 2018.
  • Evidence of Rapid Change in Katmai: the Ukak and Savonoski Rivers spill across a broad, 1.5-mile wide delta. In a landscape often defined by change, this is one of the most dynamic places in Katmai National Park.
  • 2018’s Top Ten Bearcam Moments: the people have spoken! Bearcam viewers have chosen the top ten bearcam moments of 2018. Each moment is unique and significant for a different reason.
  • Living with Bears in Churchill: The confluence of bears and people in this remote community has created a special set of challenges, which can only be met through the town’s willingness to tolerate the largest four-legged predator on Earth.

Fat Bear Week 2018 Endorsement

Last October I wrote, “There are small and fat bears, old and fat bears, young and fat bears, and just plain fat bears. But none, NONE I say, are as fat as 747.” A year later, 747 continues to demonstrate his survival skills and success at Brooks River. He’s big enough and fat enough to once again earn my official endorsement for Fat Bear Week 2018. 747 is titanic, a giant among bears.

GIF of large, dark brown bear walking down a steep hill

Bear 747 is an adult male in the prime of his life. First identified as a subadult bear in 2004, he’s matured into the largest bear I’ve ever seen.

 

But don’t just take my word for it. Bear 747 is endorsed by several of his competitors at Brooks River.

bear lying on ground

“Look, we’re all fat right now, but no one is as fat as 747. Seriously, his belly nearly drags on the ground. Even I never achieved that level of pudge. “ Bear 410

profile of bear walking along edge of river

“I keep my distance from him because I’m concerned he’ll roll on top of me.” Bear 68

402_07062016

“I’m still in awe of his size. Can he even dig a den big enough to fit within?” Bear 402.

bear with blond ears and blond coat standing in water

“Even though I’m in the Fat Bear Week bracket, I still might vote for 747. It’s the logical vote. He probably weighs at least three times as much as me.” Bear 719

profile of brown bear standing on edge of waterfall

“747 is a role model of fat bear success. I hope to be as fat as him one day.” Bear 503

bear sitting in water below waterfall

“I’m too hungry to comment.” Bear 480 Otis.

Many people who have observed 747 closely also agree with the endorsement.

bear lying in water facing photographer

“He’s all business—fishing and eating. Nobody gets fat like 747.” Jeanne R., former Katmai National Park ranger.

Too much fat is unhealthy for humans, but fat is essential to the survival of brown bears. It is a savings account against famine. Without ample fat, bears do not survive hibernation. In spring, often a season of starvation for bears, females with cubs will metabolize fat into milk to nurse their growing cubs, and adult males will use their fat to fuel their pursuit of mates.

747 won’t be rearing any cubs next spring as male brown bears play no role in raising offspring. During a season when almost no high calorie foods are available to bears, 747 will use his fat to roam the landscape for mates instead.

Other bears might be more charismatic or tug on your heartstrings, but 747 truly is a giant among Brooks River bears. He deserves your vote for Fat Bear Week 2018.

Katmai Fat Bear Week Bracket 2018 Fitz choices.png

My 2018 Fat Bear Week bracket predictions.

You are encouraged to vote for Brooks River’s fattest bear on Katmai National Park and Preserve’s Facebook page. Starting on Oct. 3, park rangers will post head-to-head matchups between well-known bearcam bears. The bear whose photo receives the most likes will advance to the next round, until one bear is crowned fattest bear on Fat Bear Tuesday, October 9th. Don’t forget to watch Katmai’s fattest bears on bearcam.

 

 

 

A bear, wolves, and a moose carcass

Although they probably inhabit all of Katmai National Park, wolves are infrequent visitors to Brooks River, and seeing a wolf on the bearcam is a noteworthy occasion.

Late one evening at the end of June and about a dozen miles from Brooks River, I was lucky enough to see wolves compete with a bear for food along the middle reaches of Margot Creek.

At the beginning of the video, a blob in the middle of the creek represents the bear as it laid on the moose carcass. Two park rangers observed the same bear on the moose about seven hours before (no one witnessed how the moose died). When presented with a large animal carcass, bears will often bury it and/or sleep directly on it to protect it from other scavengers.

Not long after I started to watch the bear, a wolf emerged from the forest. It circled the bear, perhaps testing how tolerant or defensive the bear might be. Bears are quick, capable of outrunning any human, but they aren’t as fast as a wolf, and wolves know this. Therefore, the wolf was in little danger from the bear as long as it remained wary and stayed out of the bear’s reach. This didn’t stop the bear from charging the wolf several times though (only a few of which I was able to record). Despite the bear’s defensiveness, the wolf was persistent.

low resolution photo of a bear running at a wolf

A bear defends a moose carcass by charging a wolf who approached too closely. Photo courtesy of Anela Ramos.

Soon after the wolf appeared, the bear left the carcass and a second wolf arrived. The wolves didn’t appear to be in sufficient numbers or aggressive enough to chase the bear away. Perhaps the wolves were enough of an annoyance that the bear was unable to rest or the bear could’ve been chilled by lying on the carcass in the creek for several hours. Whatever the reason, after the bear left for good the two wolves quickly began to gorge on the moose. They focused their efforts on the moose’s abdomen, thoroughly eviscerating it within fifteen minutes.

grainy photo of two wolves eating a moose carcass in a creek

Two wolves tear into a moose carcass soon after a brown bear left it unattended. Photo courtesy of Anela Ramos.

Shortly afterward, stomachs bulging with moose entrails and meat (wolves can eat over 20 pounds of food in a single feeding session), the wolves sauntered into the forest.

Events like this happen in many places where wolves and bears share habitat, but in Katmai it might be more intense in spring and early summer before spawning salmon become abundant across the ecosystem. Bears often steal the show at Katmai, but wolves also prowl the landscape, following their own strategies for survival and sometimes competing directly with bears for food.

Return to Bearcam 2018

As many readers of this blog are aware, one of my favorite places in the world is Brooks River in Katmai National Park. There, about 300 miles southwest of Anchorage, Alaska, brown bears and salmon gather to create one of the most iconic scenes in America’s national parks.

many bears standing and fishing near a waterfall

Brooks Falls on a busy evening

 

I’m pleased to announce that through the generosity of explore.org, I’ve received a fellowship to work with Katmai’s bearcams, live streaming webcams of at Brooks River.

In conjunction with Katmai’s park rangers, I’ll write blog posts (which you can read on explore.org and Medium), chat frequently in the bearcam comments, and host live chats and play-by-play style broadcasts. I hope to make time to write about my other explorations on this blog as well.

Bearcam season is almost upon us. Webcam technicians are at Brooks River now, upgrading the webcams for a better live cam streaming experience. The first sockeye salmon should arrive at Brooks River in a matter of days and the bears will arrive soon after. This will be an exciting summer, so please join me here and on bearcam.

Pebble Mine Scoping Comments

Recently, I wrote about an impending threat to Bristol Bay’s salmon: Pebble Mine. The mine, if developed, will have significant effects across some the richest salmon and brown bear habitat left on Earth.

Salmon remain the ecological and cultural heartbeat of Bristol Bay. This mine will create billions of tons of semi-fluid toxic waste, which must be treated and prevented from entering the watershed indefinitely. Impacts from development are never completely restricted to the development’s footprint either. Roads fragment habitat and vehicle traffic displaces wildlife.

When I was born, Pacific and Atlantic salmon fisheries in the Lower 48 states were already significantly degraded. Nearly 40 years later, many salmon stocks in New England, California, Oregon, and Washington remain threatened or endangered. Only a small fraction of fish return to these areas compared to historic levels. I’m not about to let this story repeat itself in Alaska, nor should you. If the mine is developed, future generations will inherit its legacy, and I predict they won’t look upon us fondly for repeating the same mistakes that killed salmon runs in the past.

Please comment during the scoping period on the Army Corps of Engineers’ Pebble Mine Environmental Impact Statement (EIS) and send those comments to your congressional representatives as well. Below you’ll find my scoping comments for the proposed mine. Feel free to copy and personalize them as you see fit. State your concerns now, so when the Army Corps of Engineers writes the EIS it will fully evaluate the mine’s impacts. Don’t let Bristol Bay’s salmon disappear because of our lust for copper and money.

The Corps is accepting comments through June 29, 2018.

salmon jumping at waterfall

Comment to the U.S. Army Corps of Engineers (submitted May 23, 2018):

The proposed Pebble Mine and its associated infrastructure poses a substantial threat to salmon and wildlife across the Bristol Bay region. Pebble Mine will straddle the watershed divide between two of Bristol Bay’s most important salmon spawning and rearing areas. I remain very concerned with the mine’s potential to negatively impact the area’s fisheries and wildlife through its wastewater, tailings, and infrastructure.

The EIS must answer one question: can Pebble Mine be developed without significantly degrading water quality and fisheries? The Corps’ has authority to deny permits under section 404 of the Clean Water Act if a proposed action will significantly degrade water quality and fisheries. This EIS should evaluate and quantify, not just identify, the mine’s potential to significantly degrade water quality and fisheries over short and long-term timespans. The EIS can begin this evaluation by appropriately defining its purpose.

A recent environmental impact statement from the Army Corps of Engineers, the Donlin Mine EIS, merely stated the purpose of the mine and the Corps’ authority to permit it (Donlin Mine Final Environmental Impact Statement – Chapter 1, pg. 1-4, 1-6). The purpose and need of the Pebble Mine EIS should be not be to simply define the project’s purpose (to mine ore) and define the Corps’ regulatory authority. It should be, as I propose, to:

  • Identify the short-term and long-term ecological effects of the proposed Pebble Mine,
  • Evaluate the mine’s and its infrastructure’s impacts on wildlife, including fish, in order to
  • Determine whether the mine’s safeguard can prevent all degradation to water quality, salmon habitat, and wildlife habitat indefinitely.

Even at very low concentrations, dissolved copper is particularly toxic to salmon, interfering with their ability to navigate and avoid predators. Its effects can manifest over minutes or hours and persist for weeks (Hecht 2007). Can the mine’s wastewater treatment plan adequately remove dissolved copper and prevent it from entering the watershed?

The mine’s tailings also pose a great risk to fish. Any accidental discharge from the pyritic tailings ponds will significantly degrade salmon habitat. Open pit mines, even within the United States, have a poor record containing their toxic tailings. Most tailings dam failures occur at operating mines and 39 percent of such failures worldwide occur in the United States, significantly more than in any other country (Rico 2008). Earthquakes and flooding hazards increase the risk of a tailings pond dam failure in the Bristol Bay region, and tailings ponds cannot be drained in the event of flooding or dam failure due to their toxic contents. The probability of a M8+ earthquake, for example, is low from year to year but remains real at any given time. Therefore, the EIS must also evaluate whether the tailings ponds can be engineered to withstand the greatest potential earthquakes and floods expected over the next several thousand years.

After the mine’s 20-year active phase, the mining company proposes to store toxic pyritic tailings indefinitely under water in the former open pit. This seems to create the potential for acid mine drainage to leach into the watershed over hundreds or thousands of years. What geologic studies suggest this is a feasible long-term plan to store the tailings? Even if subaqueous storage in the former open pit prevents the tailings from oxidizing, what safeguards will prevent dissolved copper and other toxic metals from entering groundwater to eventually oxidize and acidify as it nears the surface in a different part of the watershed?

The mine’s supporting infrastructure also creates risks for salmon and wildlife. Although salmon can navigate and migrate through streams with high sediment loads, they do not spawn in these habitats. Erosion of sediments into streams can irritate the gills of fish, smother eggs, alter feeding habitat for salmon fry, and bury spawning habitat. The effects of road construction and vehicle traffic (estimated by the mining partnership to be 35 round-trip truck trips per day) on wetlands and fisheries should also be evaluated.

The road servicing the proposed Amakdedori Port and the port itself will fragment what is now an unspoiled region of coastline on Cook Inlet. McNeil River State Game Sanctuary is one of the most important brown bear refuges on Earth, home to the largest annual congregation of bears yet observed. The road and port have the potential to displace bears moving to and from the McNeil River and Katmai National Preserve areas. Frequent work and dredging at the port area will also displace wildlife in an area that now experiences very little human activity. Other alternatives to transport ore should be evaluated.

Finally, the EIS needs to address more than the 20-year operational phase, because the mine’s waste legacy will threaten salmon for thousands of years. Tailings stored in the former open pit won’t become benign in the near future and wastewater must be treated indefinitely. Also, the possibility of an expanded mine operating over a long time frame increases the threat to salmon, other wildlife, and clean water.

Combined, the Nushagak and Kvichak rivers support about 40% of Bristol Bay’s sockeye salmon. In 2017 alone, over 56 million sockeye salmon returned to Bristol Bay and over 19 million returning to Nushagak River, the largest in the river’s history. Salmon fishing in Bristol Bay is a billion dollar industry. While commercial fisheries generate the bulk of the salmon’s economic value, the area’s tourism is almost entirely based on salmon as well. Bristol Bay is home to dozens of premier sport fishing destinations, which harbor abundant populations of rainbow trout, Dolly Varden, arctic char, northern pike, lake trout, and grayling. The Bristol Bay area also hosts some of the densest populations of brown bears ever measured. Salmon are the most important food source for these animals, and the vast majority of people who visit Katmai National Park come to watch brown bears (Strawn 2015). After spawning, dead salmon fertilize the ecosystem with nutrients derived from the ocean, boosting the productivity of otherwise nutrient-poor area.

Considering the overwhelming economic and ecological value of salmon to the Bristol Bay region, Pebble Mine could displace thousands of workers and tourists if its safeguards fail to protect salmon. Without the energy and nutrients provided by consistently large runs of anadromous salmon, Bristol Bay’s freshwater and terrestrial ecosystems will quickly transition from one of richness to poverty. In many ways, this cycle is a positive feedback loop. The productivity of the area is reliant on large runs of salmon.

We’ve seen, repeatedly, salmon populations in the Pacific Northwest and New England decimated by habitat loss and pollution. Now we’re on the brink of repeating the same mistake in Bristol Bay. Pebble Mine should not be developed. It’s in the greatest interest of Bristol Bay’s fishing industry and culture, watersheds, salmon, and wildlife for the Corps’ EIS to fully evaluate the mine’s near and long-term effects. A failure to contain the mine’s toxic tailings and wastewater would directly impact two of Earth’s most productive salmon producing watersheds. The EIS 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. In sum, the EIS must evaluate a worst-case scenario for salmon and other wildlife, since the possibility can’t be completely, or even reasonably, eliminated.

References:

Hecht, S. A., et al. March 2007. An overview of sensory effects on juvenile salmonids exposed to dissolved copper: Applying a benchmark concentration approach to evaluate sub-lethal neurobehavioral toxicity. National Marine Fisheries Service.

Rico, M., et al. 2008. Reported tailings dam failures: A review of the European incidents in the worldwide context. Journal of Hazardous Materials 152: 846–852.

Schindler D. E., et al. 2003. Pacific salmon and the ecology of coastal ecosystems. Frontiers in Ecology and the Environment. 1(1): 31–37.

Strawn, M. and Y. Le. 2015. Katmai National Park & Preserve Visitor Study: Summer 2014. Social and Economic Sciences Research Center, Washington State University, Pullman, WA.

 

Addendum: My comment was apparently too long for the Corps’ comment portal on the Pebble EIS website. So if you use my comment in full, you might receive an error message. To work around it, you can attach the full comment as a PDF or Word document.

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 stabilize 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.