Alaska’s brown bears – Family Ursidae -- are the charismatic megafauna that everyone wants to see…from a distance. Photographing them means a trip to isolated streams, a long lens, and good serving of respect for their power. In terms of climate change, brown bears are affected by shorter, milder winters which disrupt hibernation and mating, as well changes to salmon runs and other food sources. As part of a rich ecosystem, bears offer stories of their own, as Julianne Parker shows us.
I don’t bother scraping the splattered fish guts off my boots. I’d rather smell like rotten fish than fall behind out here. I trot forward, closing the gap between the algae and fish carcass-covered rocks I slipped on and where Milo trudges steadily ahead.
Our window of opportunity this morning is small. As a wildlife biologist for the U.S. Forest Service and recreational photographer, Milo Burcham doesn’t afford much patience to the clumsy journalist slowing him down.
“They’ve definitely been feeding here this morning,” he says as I resume my position at his heels. “And not too long ago.” He points at a carcass whose split belly pours out bright orange peapod-sized eggs that scatter out across the rocks. Trails of red spill from the exposed flesh and stain the rocks it rests on, distinguishing it from the rest. This fish is a fresh kill.
The banks of the stream are littered haphazardly with salmon carcasses along the braided shallows, challenging us to hop from one clear patch of slick river rock to another to avoid landing atop the decaying remains.
Some of the carcasses are evidence of a successful first and final journey upriver. Their scales are patterned with sickly patches of purple and green and peel off in wispy flakes of yellow decay – a sign of a helpless, yet natural death. Other carcasses are mere skeletons – assiduously rid of any morsel of flesh or gut, waiting for the high tide to wash their bones to sea. But the most intriguing and stomach churning of them all are the plump ones, whose scales still hold a healthy gray-blue shimmer, and whose deaths are marked by giant bites splitting their stomachs or tearing off their heads.
For a city-dwelling Oregonian whose most wild encounters are the coyotes that terrorize suburban pet owners, and the rusted, dismissible black bear warning signs posted at the entrance of city-enclosed hiking trails, seeing a predator in the wild was far from believable. It was this naivety that had led me running down a forest-lined Alaskan road at dusk the day before – without a can of bear spray. I had ignorantly assured my jogging partner that it was unrealistic to see a bear roaming so close to town. No sooner had the words been heaved breathlessly from my mouth did the thicket of blackberries we ran next to rustle. From above the bush poked the massive head of a black bear.
I follow Milo silently upstream, haunted now by the memory of standing so close to such a mesmerizingly massive creature. Patience and stillness were two reactions far from instinct as I had stood staring into the beady eyes of a creature four or five times my weight, divided only by a tangle of bushes. The fear had been distinct – driven by an unfamiliar sense of inferiority. It reclaims me now as Milo slows and points over the tall sedge grass. Three Alaskan brown bears wade across the stream – a mom and two cubs.
A morning “hunt” is perhaps too generous of a way to describe how these bears dine. “Feasting” or “casually selecting from a myriad spread of recently decomposing beached flesh” is probably more accurate. At least for the cubs. The mother has developed a taste slightly more sophisticated. She instead makes a wide-mouthed single plunge into a densely packed group of salmon so exhausted from their pilgrimage upriver to spawn that they put up no effort to flee from the approaching shadow. She pulls a live, flapping fish to shore and pins it down with one paw and chomps into its stomach, searching hopefully for a female belly filled with un-laid roe – a common behavior for the overindulgent Alaskan brown bears.
The mere physical size of these bears serve as evidence to a diet rich with protein and fat from the easy and abundant access to the fish. Brown bears are the same species as what is commonly called grizzly bears in the Lower 48 and inland Alaska, but the impressive difference in size (ranging anywhere from 200 to 700 pounds heavier) begs for a differentiating identity. In coastal regions like here in south central Alaska, the bears are so spoiled in salmon abundance they can afford to simply bite off a mouthful of the most protein and fat-rich parts of the fish – the roe, brains, and skin, and discard the rest.
Earlier in the salmon hunting season – starting with the runs of Chinook near the end of May – the bears can’t afford such luxury. Recently out of their winter hibernation, which can last as long as seven months, they spend the first months of spring foraging for early emergent vegetation and leftover berries from the previous fall. So by the time the first salmon runs begin, the bears become fastidious eaters. Two months ago, the banks of this stream would be clear of salmon carcasses – evidence of a protein deprived population hungry for the 3,000 calories per fish to pack on their lost winter weight.
But by the time the chums and pinks make their way upstream toward the end of July and early August, and the bears have had their fill of salmon and can be far more self-indulgent. Thus, we have the carcasses that line the stream today – whose flesh often remains mostly intact aside from a missing head, bite out of the belly, or the occasional fish whose skin has been peeled off.
The Copper River, which empties into the Prince William Sound, has some of the most productive salmon runs in the world. So food is a rare concern for the spoiled creature with virtually unlimited access to fish, vegetation, and terrestrial meat. The bears also have vast access to refuge areas to protect the species from hunting exploitation, and are limitedly threatened by development or logging plans. The ecosystem is healthy, relatively untouched, and showing little sign of distress.
There’s no imminent disaster here.
So if you ask a wildlife biologist what the threats are to the brown bear population in the Prince William Sound, they’ll shrug and admit the habitat is currently quite stable. Or, as Charlotte Westing puts it, the system here is still “unbroken.” Approaching science with preventative instead of reactionary methods is the reason she came to Cordova. Yet limited and demanding funding models usually puts bear research on the back burner – far behind the lucrative, and highly marketable, wild Copper River salmon.
Yet the brown bear plays a critical role in both cultural and commercial value for the community, and in the productivity and synchronization of the ecosystems. Understanding their role however, is usually offset by a combination of limited resources and their fateful stigma as the livestock-terrorizing, human-mauling villain, or the trash-digging nuisance. In other words, among Cordova’s highly studied ecosystem, the brown bears remain an under-researched species.
The mother and her two cubs soon disappear into a tall field of pale sedge grass, leaving behind an eerie stillness in the steeply walled valley. My veins pulse with a new kind of energy – one inspired by a moment so rare and so raw, it’s intoxicating. Only as the adrenaline fades do I begin to take notice of the terrain for the first time since we arrived. The upper parts of the tooth-tipped ridges are blanketed with scree and snow that eventually dissolve into undulating growths of citrus spruce and western Hemlocks. The vastness of terrain is perhaps the most awe-inspiring part of Alaska, expanding so far it eventually melts into a blurred line of land and sky. I imagine it once expanding all the way down to the Lower 48, where diminishing pockets of wilderness still remain in their true, unkempt wildness.
As I write this from the warmth of my home in Eugene, where I now dream of the vastness of untouched space, the reason to study an unbroken system filled with diverse and thriving ecosystems seems pleadingly obvious – to keep it that way.
The system is still unbroken. Westing’s description is a generalization, and an arguable one at that, but a standout comment coming from a corner of the world often associated with melting ice caps and dwindling sub-arctic populations. Perhaps her statement is merely in contrast to other, more vulnerable and changed, systems where “broken” would be a far from an understatement. But nevertheless, here in Cordova, Westing has a rare opportunity to influence the future of an ecosystem whose health is not on the brink of disaster.
“Everywhere else you work, you would basically be trying to fix things that are already broken,” she says. “Here, you can work on the preventative side.”
Ideally. Yet tight resources make species that are at the bottom of the priority list – ones that aren’t of high economic or food value for people – difficult to study. Alaskan brown bears are one of such species. They are expensive and challenging to track, and a generally undervalued contributor to the ecosystem, which makes it difficult to provoke much interest in allocating funding their direction. So while general life history of the species is well understood, their baseline information in relation to the Prince William Sound is limited.
“Competition between different areas of the state and different species tightens the budget,” Westing says. “But the biggest questions we need to know are what’s our population and what’s our exploitation rate. If you don’t know these two things then you don’t know if your harvest is sustainable. Without that baseline piece of information, anything else is irrelevant.”
Questions addressing the brown bears’ habitat vulnerabilities, or accurately observing shifts in population size or health, therefore take a backseat to other research priorities. This is why most of the information we do know about Alaskan brown bears that reside around the Prince William Sound is behavioral traits based on observation and assumptive comparisons between brown bears in areas that have more research opportunities available. But because there’s no urgent need to mitigate an ecological crisis affecting the brown bear population, progressive and preventative research remains at a standstill.
Research biologist Milo Burcham and I wait patiently in his secret bear-spotting valley – an hour’s boat ride from the docks in Cordova. Only a few slow minutes pass before we see the slow-moving shadows between the dark and veiled corridors of trees. One by one they emerge – three adults in all, shifting their heavy weight grudgingly from one shoulder to the other, padding their paws against the spongy, moss-covered floor.
They climb atop boulders and lope their heavy, fat-ridden bodies down the talus slope towards the stream below. It’s at this union of rock and water where the bears begin their hunt. They waddle into the stream, lazily swinging their massive paws at the humps of the many salmon. Without great effort the darkest of the three catches one by its top dorsal fin and drags its thrashing body to a flat boulder near the stream’s edge.
But within minutes the largest of the bears takes notice of our presence across the stream, standing on its hind legs to get a better look. As if following an order, the other two obediently begin their retreat back into the woods. Milo curses under his breath, whispering that the breeze cutting through the valley walls must have carried our scent to the wary bears. But they leave without rush – with no sign of skittish fear or assertive confrontation. Slowly. Lazily. Two of them drag their fresh morning’s kill into the forest with them, where they will likely leave behind the half-eaten flesh on forest floor.
This frugal behavior – though likely induced today by our unwelcomed presence – is a habit the bears developed long before humans began interrupting their morning meal. Dragging half-eaten carcasses into the forest to indulge in another bite or two, serves an important ecological function that benefits far more than these bears.
Those salmon carcasses, and the salmon that cycles through the bear, deposited later as feces, are packed with ocean-derived nutrients. These nutrients release nitrogen and phosphorus for the trees to feed on, and provide a concentrated fertilizer as the flesh decomposes into the soil, nourishing the forest and increasing the productivity of the entire ecosystem.
So just how big of an ecological role does a single bear play?
Let’s assume the average sized fish is five pounds, and that on a given day the average bear catches forty salmon (a common estimate among researchers). If the bear abandons roughly three-quarters of what it catches on the forest floor, that’s about one hundred and fifty pounds of nutrient rich salmon flesh feeding the soil. Per bear. Per day. Add that to the contribution of salmon-rich feces the bears also leave behind and you have a living, breathing fertilizing machine.
It’s no coincidence that the coastal Alaskan forests that grow near salmon streams are so dense and productive. As the fertilized vegetation grows more abundant, it can also support a larger population of wildlife. So a moose, or other ungulate species, that might feed on the bark of a salmon-fertilized willow tree will benefit more from its nutrient dense food and become more productive itself, hence having more calves. Come spring, when brown bears commonly prey on moose calves, the bears will benefits from the healthier and more abundant moose population. The cycle can be broken all the way down to increased invertebrate hatchings in nutrient rich bear feces, which provides more food resources for the juvenile salmon preparing for their pilgrimage to the sea. Or the food source the partially eaten carcasses provide to scavenger species like gulls, foxes, or even the occasional deer or mouse that nibble the salmon skeletons clean. The cycles go on and on.
Yet, these feedback loops are as sensitive as they are intricate, and the smallest of changes in a single part of these ecosystems can quickly and easily disrupt its synchronization.
Take, for example, a recent winter in Cordova when record snowfall broke twenty-seven feet, with ten feet falling in just two weeks. The brutal persistence of that winter led to a late spring and a delayed emergence of the bears from their winter hibernation. So not only were the bears coming out of dens hungrier, but the early emergent vegetation the bears usually feed on until the salmon runs begin, were also not yet ready to eat. So the cub survivorship was low and the ecosystem lost a large portion of an entire year’s cub cohort.
But ecological change is no new phenomena. Disruption is not always a bad or unnatural occurrence, as population oscillations have naturally existed far before scientists arrived with radio collars, data charts, and microscopes. The questions that many scientists in the Prince William Sound are hoping will guide research on Alaskan brown bears in the future is to identify whether those changes are man-induced, or unnatural to a given environment.
These unforeseen events that cause fluctuations in a population’s abundance is what Westing refers to as environmental stochasticity, and is largely what the research in the Prince William Sound region is up against. Understanding and predicting when, how, and why an environment changes and what impacts those changes may have on the ecosystems is what divides reactionary science from preventative.
The Prince William Sound is a mecca for ecological research conducted by groups such as the Prince William Sound Science Center, the Alaska Department of Fish and Game, and the U.S. Forest Service – each with their own questions, motives, and research objectives to study and learn how to better interact with this intricate and unique ecosystem. But for reasons previously addressed, bears aren’t the focus of these research projects.
“There’s a lot we don’t understand about bears,” says Westing. “It goes back to our long history with predators and how we think that the less of them the better. So it’s a complicated web to try to navigate how to get more information about bears, and more money to study them, to maintain those appropriate numbers.”
Aside from holding little economic value, bears also carry a fateful stigma for being either the garbage-digging nuisance or human-terrorizing villain. All this to say that a de-valued existence means an understudied population, so among the science community in Cordova there are a lot of “what ifs,” hypotheticals, and speculation when it comes to the Alaskan brown bear.
Are hatchery salmon, for instance, causing bears to become dependent on an unnatural source of protein, change their foraging techniques, and physiologically increase their metabolic needs?
How might the species be affected by climate-induced phenological changes that impact what spring vegetation is available to feed on when they emerge from hibernation?
Or, how might the population be impacted if dietary demands for terrestrial meat are affected by an emergence of the warmer weather-loving winter tick – a major culprit of moose fatality in the continental United States?
But before any of that, just how many bears are in the Prince William Sound?
As far as researchers know and can predict, Alaskan brown bears in the Prince William Sound currently have a healthy and stable population. Observation, comparable population data, and speculation serve to question whether that strength can be sustained and what factors might limit that strength. But herein lies the basic goal and challenge for the scientists who work in a corner of the world that still contains some of the healthiest and most thriving ecosystems on the planet: How can science serve as a tool to understand and protect an ecosystem or species that isn’t urgently demanding attention?
How can science be preventative instead of reactionary?
Once the bears make their final retreat into the forest, we’re left alone. Or at least alone in the sense that perhaps only us city-bred folks might feel. The valley still hums with life. The gulls squawk and circle around the remains of the bears’ morning catches. The salmon fight their way up the shallow riffles before high tide sets their day’s progress back. An eagle soars high above us in line with the stream’s path until it disappears around a grove of trees to journey to the sea. The land has a pulse. One that has beat with precision, deliberation and energy for thousands of years, thriving in its near completely untamed and unrestricted wildness.
That’s why it’s worth studying.
It’s still unbroken.