Friday, September 21, 2018

Bunnies #2: Stranger than we can Imagine

Dreaming about snowshoe hares and blueberries up in the Brooks Range near Wiseman, Alaska, soon turned into long days of capturing both the furred and the fruit. Productive days were followed by lively evenings in the bunk house with two graduate students from the University of Alaska Fairbanks; their research advisor, Knut Kielland; and their research partner from the National Park Service, Donna DiFolco.

This group is not the first to try and tease out mechanisms behind a roughly 10-year cycle of snowshoe hare population highs and lows. When hare populations go up, lynx numbers go up, too. When the bunnies crash headlong into a population low, lynx follow. Hungry humans all across the North have been aware of this cycle for hundreds of years, since hares were a staple in their stew pots. I’ve been aware of it since my second semester of college. The lynx-hare cycle has been highlighted in ecology textbooks since 1942, when British ecologists Elton and Nicholson did a thorough quantitative analysis of lynx numbers in the fur trapping records of the Hudson Bay Company.

Canada lynx and snowshoe hares and are linked together as predator and prey in a 10-year cycle of population highs and lows. They also share a key adaptation: huge, furry feet that help them float on deep snow. Photo by Emily Stone.
Knut Kielland has been a wildlife biology professor at University of Alaska Fairbanks since 2000, and one evening in the bunk house I peppered him with questions about the state of research on the lynx-hare cycle. He conducted his own survey of published fur harvest records in Alaska. As part of the Bonanza Creek Long-Term Ecological Research Program, he has been monitoring hare numbers since 1999. During both studies, he found that same, roughly decadal, cycle. Like lots of other scientists, Knut and his students are trying to figure out why. When I asked Knut about his favorite theory, he didn’t have just one answer. Instead, after listing off a bunch of recent research, he chuckled and summarized, “As science usually proceeds…people just keep picking away at the problem.”

Near the end of our conversation, Knut also shared a quote from J.B.S. Haldane, who wrote: “Now, my own suspicion is that the universe is not only queerer than we suppose, but queerer than we can suppose.” The accuracy of that quote didn’t sink in until I’d taken the list of scientists and studies Knut had mentioned and used Google Scholar to try and make sense of it all in my own mind.

The classic, top-down, predator-driven theory posits that as hares increase, the number of lynx who feed on them goes up, too. Hares get eaten. Lynx have more babies. Soon there are too many lynx and not enough hares to feed them all. The lynx population goes down, hare numbers recover. The cycle starts over. Most scientists now believe that this is oversimplified.

For example, predators don’t just kill hares by eating them. As Western society has discovered, living a hectic, stressed-out life can have many sub-lethal impacts on your health, and on your ability to have babies. Rudy Boonstra, et al, (1998) hypothesize that when lynx numbers are high, hares experience more failed attacks on themselves, successful attacks on their neighbors, and frequent encounters with predator sign, i.e. lynx scat.  Therefore, hares may spend more time being vigilant and less time seeking out quality twigs to browse on. Put yourself in their (snow)shoes for a second and it’s easy to see why this could lead to a decline in health and reproduction.

What if predators aren’t the hares’ only source of stress? DeAngelis et al, (2015), found that when numerous hares browse heavily on their favorite winter foods, those willow and birch shrubs increase the concentration of anti-herbivory chemicals in their tender new twigs, which makes them less palatable and nutritious to hares.

Do the chemicals that plants produce to protect themselves against hares play a role in the 10-year cycle of snowshoe hare populations? This sharply angled twig is a sign of a hungry hare. Photo by Emily Stone.
Therefore, at the same point in the cycle when hares would be experiencing the most stress from high numbers of predators, they also may be left eating woodier and more toxic twigs than ideal. The resulting food stress could impact current and future reproduction, which could prevent an immediate population rebound, and may be one of the drivers of the 10-year cycle.

So, is the cycle’s driver top-down, fueled in one way or another by lynx? Or is it bottom-up, impacted by the chemical defenses of lowly plants?

In an extreme version of a top-down hypothesis, Selas (2006) suggested that the sun itself might play a role. Our sun goes through an 11-year solar or sunspot cycle where it emits varying levels of radiation. When sunspots are low, the ozone layer is thinner, more UVB radiation (the rays that cause sunburns) gets through, and the plants produce chemicals that defend against sunshine instead of hares. Plants become more nutritious, and hares increase. Except that the sun is on an 11-year cycle, while hares typically fluctuate on a 9-10 year cycle. Close, but no cigar.

Herbert Archibald (2014) also looked to the sky for answers. In addition to the 29.5-day lunar cycle we watch every month, our moon has an 18.6-year cycle of wobbling along its path around the Earth. Every 9.3 years (half the cycle) the orbits of moon and the sun line up and join forces. Tides are more extreme, and the full moon rises as the sun sets, resulting in “nights without darkness.” Archibald hypothesized that the moon’s cycle could drive the hare’s cycle. Hares rely on the cover of darkness to avoid predation, feed themselves, and care for their young. If a bright moon prevents darkness from falling, Archibald suggested, this could reduce hares’ fitness and reproduction. He found that the average hare cycle lasted 9.4 years—which is intriguingly close to the moon’s.

Archibald’s moonlit mechanism seems a little weak to me. Except, what if the moon’s 9.3-year cycle also impacted the amount of UVB radiation that reaches Earth?  Selas (2013) has proposed that at the peak of the moon’s cycle, it interacts strongly with the Earth’s magnetosphere and more cosmic radiation gets through. Plants respond by defending against the UVB radiation instead of hares, and this increases their palatability to hares. Geophysicists don’t think this effect is very strong. Plant physiologists think it just might be strong enough to form an “anchor” in the hare’s cycle, keeping it on schedule, while other factors drive it up and down. Knut is intrigued, because the moon’s 9.3-year cycle is the only one that matches the observed patterns in the lynx-hare cycle.

Hungry lynx, stressed-out bunnies, plant toxins, sun spots, and moon cycles—I never would have guessed that studying snowshoe hares could mean looking beyond our atmosphere, or even beyond the forest canopy. Research continues. People have made tremendous contributions, says Knut, but he is suspicious when they say, “We’ve solved it!” “Being a Norwegian Lutheran,” Knut began, “if someone makes extraordinary claims, I expect extraordinary evidence.” So far, that evidence has been elusive. Maybe information we gathered during this week of field work will add a another piece to the puzzle.

Emily is in Alaska for the summer! Follow the journey in this column, and see additional stories and photos on her blog:

For 50 years, the Cable Natural History Museum has served to connect you to the Northwoods. Come visit us in Cable, WI! Our new exhibit: “Bee Amazed!” is open.

Friday, September 14, 2018

On Top of the World

There was something in the quality of the light that glowed on the green slopes of Mount Fairplay. For one, it was evening light, which is something that’s been rare in the land of the midnight sun. That, plus the clean scent of fresh pine boards in the latrine, and the fact that it wasn’t raining, made me pause and decide to spend the night at this rest area on the Taylor Highway on my first night driving homeward out of Fairbanks.

A few hours later I woke with a full bladder, rolled out of the sleeping platform in my station wagon, and grabbed a headlamp. Relieved, though blinking and squinting as I walked back, something bright caught my eye. A full moon was rising over Mount Fairplay. After turning off my headlamp to see the moon, my eyes adjusted and a sheet of twinkling stars emerged from the dark as well. I’d almost forgotten they existed. For the first time, it really sank in that I was on my way home. A deep breath of gratitude filled my lungs.

As the fog of sleep cleared and more stars appeared, awe began to expand in my heart. Then it exploded. Curtains of vibrant lights were moving just above the horizon. The aurora! My jaw must have dropped as I stumbled backward to lean against the car, and tears welled up as I tilted my head back for a better view. The moon hung full and bright on my east. To my west, spruce trees were silhouetted against the faint, rosy afterglow of the setting sun. And all across my southern sky, northern lights danced in curtains of green and white and pink. The curtains were woven of many wispy streaks, as if I was seeing the individual particles of solar wind blazing through our atmosphere.

Northern lights dance over spruce trees in Alaska. Photo by Emily Stone.
The shimmering sheets swirled and then faded to a gentle fog across the stars, like the smoke that hangs in damp air when the glitter and crackle of Fourth of July fireworks have ended and cars stream away down the dark road. Was that all?

A little spot of light near the top of the sky appeared and intensified. I fixed a gaze of hope on the glow, and it grew before my eyes into a dancing swirl of pink and white and green that showered down all around me. I used to love ducking inside the dangling twigs of my grandpa’s weeping willow tree to find a secret world filled with soft light and magic. That willow went down in a storm years ago, but its glowing ghost now held me inside the same world of light and magic.

Magic indeed. The sky looked as if someone was blasting the Earth with a spray of fairy dust. Which in fact, was nearly true. Our Sun, though, is not some benign sprite. It is like a young wizard who does not yet know how to control his own power. The Sun’s light gives life. The sparkling shower of solar wind and radiation that he shoots at us threatens destruction. Mostly, those charged particles curve harmlessly around the force field of the Earth’s magnetosphere.

Near the poles though, where the magnetic field dips and our defenses are low, some of the solar wind rushes in. Here, the gasses in our atmosphere intercept the marauders, capture their energy, and transform it into colored light. When the solar winds are particularly strong, they can burst through the Earth’s defenses and interrupt radio communication, disrupt power stations, and damage satellites. Northern lights are not just an awesome benefit to living on Earth; they are an absolute necessity to our survival. Our Earth defends us. And the result is unspeakable beauty.

The most magical part to me is that it’s not magic at all. It’s physics, and chemistry, and nature. And we (or at least the scientists) understand what’s happening.

What a miracle that is. What an amazing gift to both have this incredible beauty surrounding us on Earth (on Earth, which we sometimes think of as rock and dirt, and politics and pollution) and to understand it. The Earth receives magic dust from the Sun that makes light dance upon the sky. That’s what we get for living on Earth. That’s what we get.

Emotions I couldn’t name welled up inside and spilled over into hot streaks of tears on my cold cheeks. The lights were dancing and streaking and changing colors like a time-lapse video of clouds streaming off a mountain peak. Moving curtains faded to smoke and came back. They quivered. Ghosts shimmered in front of the stars.

Then I noticed a humming in the air like the buzz of electricity through a wire, like the buzz of a bumblebee on fireweed, like a classroom light that’s trying to turn on. I cocked my head and also heard a chord, like choir holding a note. As the lights faded to smoke the sounds grew louder. It changed. It moved, coming from a different angle. It formed a higher note, and then it stopped. A sleepy bird peeped from the spruces.

I was sleepy, too. My toes were cold, my fingers were numb, and I ached to crawl back into my warm sleeping bag just as badly as I ached to stay out here all night so as not to miss a single instant of beauty. Lights were dancing, falling, streaking, coming together and bursting apart like fireworks. When they faded a bit, sleep won out and I crawled back into my warm cocoon. I knew that more gorgeous vistas awaited me in the morning on my drive over the Top of the World Highway. More beauty awaits me every second of every day.

Anyway, we will never be able to experience all of the splendor that this world has to offer. There is just too much of it. And there will always be more. But I am grateful for this abundance of beauty. And I am also grateful that on clear nights my body has ways of getting me outside to see it.

Emily is in Alaska for the summer! Follow the journey in this column, and see additional stories and photos on her blog:

For 50 years, the Cable Natural History Museum has served to connect you to the Northwoods. Come visit us in Cable, WI! Our new exhibit: “Bee Amazed!” is open.

Friday, September 7, 2018

Bunnies #1: The Side Benefits of Science

“According to the Denali bus driver’s manual, hitting a snowshoe hare will only ‘produce a momentary loss of traction,’” quoted our bus driver, Drew, over his microphone. We’d been watching bunnies dart across Park Road on the way into Camp Denali. “During highs in the population cycle,” Drew continued, “they’re so abundant on the roads that it’s hard to miss them all.”

Scientists as well as drivers across Alaska are quite aware that hares numbers are on the rise. In Denali National Park, the last peak in their 9-to-11 year cycle occurred in 2009. Since 2012, wildlife biologists with the National Park Service have been keeping track of hare numbers through a particularly kid-friendly method.

“We can’t just walk out there and say ‘hey animals, come out, I want to count you,” explained Denali National Park’s wolf technician, Kaija Klauder, to a group of high school students from Anchorage who were attending a summer science camp. “Luckily,” she continued, “all animals poop, and that’s awesome for science.”

High school students from Anchorage hike through spongy tundra to get to our second hare pellet count grid. Despite cooler temperatures, sunshine, low bugs, and great scenery made doing the science even more exciting. Photo by Emily Stone.
Pellet surveys can be tedious, so I was impressed by how enthusiastically the kids began their work. Park scientists have established 8 different grids of 100 plots apiece. Within each plot, a pair of counters was tasked with finding every small, brown, Skittles-shaped hare pellet, marking it on the data sheet, and then tossing it away from the plot so that it won’t be counted twice. The one-foot-radius plots I helped count had at least 15 pellets each, and some kids found over 100 pellets in a single plot. That seems like a lot, and it is more than they’ve found during the past four years. Back in 2012, though, three years after the previous high in the hare population, pellet counts were 50 percent higher than this year. It’s impossible tell when the population peaks until it starts going down, but it seems like they have room to grow.

Snowshoe hare pellets look kind of like Skittles that are made out of sawdust. The abundance of pellets can help scientists estimate the density of hares in an area. Photo by Emily Stone.

Looking for the pellets gave us all a closer look at the moss, moose poop, fungal mycelia, mushrooms, and beetles inhabiting both a spruce forest and a willow thicket.  We found a moose bed in the moss, too, and admired flowers in the spongy tundra. Who knows what other subconscious observations the students made with their noses to the ground? Science has a way of sneaking up on you. Studying one organism leads to questions about others, and just crashing around in the woods for a few hours inputs data into our personal sensory computers.
Kaija, the National Park Service biologist who led our pellet count survey, pointed out the features of a moose’s bed. Photo by Emily Stone.
About a month later, in mid-August, I joined Claire Montgomerie and Matt Kynoch, two graduate students from the University of Alaska Fairbanks, to help with their snowshoe hare fieldwork. They are partnering with the National Park Service near the tiny town of Wiseman in the southern foothills of the Brooks Range.

Just as in Denali, we saw plenty of hares along the Dalton Highway as we drove north from Fairbanks. I was mesmerized by the rolling expanses of boreal forest and the undulating silver stripe of pipeline that mostly paralleled the road. For me, this wasn’t just an exciting opportunity to help with research; it was an excuse to explore new landscapes in The North. At the sign marking the Arctic Circle—66.33 degrees north latitude, I took a selfie with a huge grin. I love going North.
While the Dalton Highway is riddled with potholes and washboards for much of its length, the scenery along its length more than makes up for it. Photo by Emily Stone.

Doing research can take you to some amazing places! Photo by Emily Stone.
I was still smiling the next morning as we wound through soft green hills and along the silvery braids of the Koyukuk River to access two different research sites established by the biologists from Gates of the Arctic National Park. Along one rutted gravel road we set 14 live traps baited with alfalfa cubes and carrots. Firmly compacted moss in the hares’ runs and dense clusters of brown pellets indicated good spots to place the traps. Claire pointed out exposed dirt on the road cuts where hares have been recorded coming to lick the soil. Our goal there was to recapture hares who had been previously deployed with GPS collars to track their use of the mineral licks.

We used live traps baited with carrots and alfalfa cubes to catch hares in the Brooks Range. A piece of tarpaper over the cage provides protection from rain and sun, as well as making the hares feel more secure and hidden. Photo by Emily Stone.
Next we parked at a pipeline access road and walked in to a trap grid used for mark-recapture surveys. There we spent a couple hours finding, baiting, and setting over 30 traps at established locations. We also picked handfuls of tart, red highbush cranberries, savored the sweet treats of dwarf raspberries, and admired the luminous white flowers of bog-star. After dinner, we ambled through thick beds of moss and lichen behind our bunkhouse and picked blueberries until dark.
Lucky for us, the blueberries were perfectly ripe in the Brooks Range during our snowshoe hare field work in mid-August. Photo by Emily Stone.
I’d been seeing and hearing about the population dynamics of snowshoe hares since I arrived in the Alaskan interior. I was thrilled to find an opportunity to learn more, and to experience research firsthand. Now that I was actually up in the Brooks Range, the side benefits of fieldwork were becoming clear. What would the rest of the week bring? I fell asleep dreaming of blueberries and bunnies.

Emily is in Alaska for the summer! Follow the journey in this column, and see additional stories and photos on her blog:

For 50 years, the Cable Natural History Museum has served to connect you to the Northwoods. Come visit us in Cable, WI! Our new exhibit: “Bee Amazed!” is open.

Friday, August 31, 2018

A Naturalist on Ice

Helmet, crampons, harness, warm layers, trekking poles, camera. My pack was heavier than usual—and my excitement stronger—as we caught glimpses of white ice and blue crevasses beyond the canyon’s edge.

Two days after my first hike up the Harding Ice Field trail in Kenai Fjords National Park, I was at it again. The damp, gray, foggy weather was the same, but my mission was different. This time I was going to walk on the glacier. After watching adventure movies and adding a healthy dose of common sense, it’s not an adventure I’d felt comfortable doing solo. Nick, a guide from Adventure 60 North in Seward, led the way, and a retired doctor and his architect wife from Colombia (she runs the family’s banana plantation on the side) completed our little crew.
From the Marmot Meadows Overlook we watched other guided groups walk on the ice. They looked like tiny ants on such a giant landform. Photo by Emily Stone.

At the Marmot Meadows overlook we began to descend out of the lush field of wildflowers and straight down toward the white, blue, and brown wrinkles of the glacier along a rocky trail. The National Park Service doesn’t maintain this route, but several local guide services use the path.

The side of the glacially carved valley was steep here. At the height of the last ice age, 23,000 years ago, Exit Glacier filled the entire gorge. When our footing transitioned from ice-scoured bedrock to piles of loose gravel deposited by melting ice, Nick paused to point out that in past years he could walk straight out from this bench onto the ice. The dirty edge of the glacier now lay at least 20 feet below.

It was an abrupt transition from lush meadows down to fresh gravel
and then onto the ice. Exit Glacier is shrinking, so the hike keeps getting longer.
Photo by Emily Stone. 

According to the Park Service, the terminus of Exit Glacier retreated 1,635 feet up its valley and thinned by almost 300 feet between the years of 1950 and 1990. The rate of thinning has only increased since then. In the past ten years it has retreated 1,000 more feet. Former President Barack Obama visited Exit Glacier in 2015, to highlight the effects of climate change. The toe of the glacier has become so unstable that visitors are no longer allowed anywhere near it. We’d hiked 1.5 miles up steep switchbacks and flights of stone stairs in order to gain access.

At a level spot in the dirt we paused again, this time to layer on winter clothes, tighten rescue harnesses around our waists, fasten climbing helmets under our chins, and strap saber-toothed crampons to our boots. Nick traded his trekking pole for an ice axe. His big backpack was full of rescue gear. “Keep your steps high and wide,” he repeated as we made our first tentative moves in the mean-looking crampons. “High, wide, high wide,” I reminded myself. And, finally, I was walking on a glacier.

The landscape was a gracefully sculpted expanse of luminous snow and ice, sprinkled liberally with brown dirt. Scalloped divots at a variety of scales were rimmed in a dark lace of dust that had been picked up, ground down, and then freed from melting ice. Rivulets of water cut narrow ravines through the dirty surface and created small, white-walled canyons with intensely blue bottoms. Those small ravines probably flowed along the tracks of healed crevasses.

As the ice moves over uneven ground, crevasses open and close. Deep within the glacier, high pressure allows ice to move through plastic deformation—similar to molten lava. Crystals bend, deform, and slide past each other. Near the glacier’s surface, though, it is more brittle. As the mass maneuvers around corners and over obstructions, the surface must stretch wider. When the ice stretches past its stress limit, crevasses crack open. Later, they may squeeze shut, leaving only a linear scar.

Crevasses are cracks in the glacier that open and close as the ice moves over uneven terrain. Photo by Emily Stone.
Stepping high and wide, and being sure to kick our crampons into the slippery surface with each step, Nick led us to a narrow crevasse. His long legs straddled it easily, and one by one we came forward to have a look. Although it was narrow enough that none of us could have fallen in, it was still comforting to have Nick’s steady hand on my harness as I gazed into the deep blue depths.

Nick, our guide from Adventure 60 North, knew the glacier well and was able to show us unique features while staying away from the more risky areas. Photo by Emily Stone. 
Crevasses can be a hundred feet wide, thousands of feet long, and hundreds of feet deep. Water-filled crevasses may reach all the way to the glacier’s bed. Perhaps this crevasse had stayed small because of the absence of water.

Nick also led us to the edge of a moulin. As before, he held onto our harness and we peered into it one-by-one. Water may have excavated this roughly circular, well-like shaft out of an old crevasse or found some other weakness in the ice. Either way, we watched a tiny stream glide over the surface and then cascade into the smooth, spiraling hole.
Moulins are roughly circular, well-like shafts in glacial ice. Water and sediment flow down into them. Photo by Emily Stone
Sometimes the water will make its way down a moulin for a short distance and then find a horizontal route through the ice. Sometimes the water makes it all the way to the ground surface and flows under the glacier. Moulins play an important role in carrying water and sediment from the surface of the glacier into its depths. Mount Telemark, a 380-foot-tall old ski hill in Northern Wisconsin, was probably built by water-born sediment that poured into a large moulin 14,000 years ago at the end of the continental glaciation. I was thrilled to see a much smaller version of this glacial feature in action.

We all took a few more photos before making our way off this foreign land. While on the ice it felt like a fairytale winter. Luminous clouds hovered above, and luminous ice sat deceptively solid below. High and wide we stepped closer to the edge, the ratio of dirt to ice under our feet increasing steadily until we were back on the piles of sediment at the glacier’s lateral margin.

Our world is changing quickly. The thought that these glaciers are melting is a little terrifying. And yet, I’m intensely curious to witness the landscapes they will reveal. Several thousand years ago, the Chippewa and Superior Lobes of the Laurentide Ice Sheet melted away from the place I now call home. I ski on piles of sediment they left behind. I swim in lakes formed by melting ice blocks. Many times I’ve craned my neck back and gazed upward, trying to imagine the mile of ice that once loomed above my head. After exploring these living glaciers of Alaska, I feel like I better understand my own home.

Emily is in Alaska for the summer! Follow the journey in this column, and see additional stories and photos on her blog:

For 50 years, the Cable Natural History Museum has served to connect you to the Northwoods. Come visit us in Cable, WI! Our new exhibit: “Bee Amazed!” is open.

Friday, August 24, 2018

Hey Bear!

I've been doing a fair amount of solo hiking while in Alaska, which means that I'm in the habit of saying "hey bear!" loudly at regular intervals. I had thought about getting bear bells to attach to my pack, but I'm glad I didn't because the rangers here say that they don't work nearly as well as the human voice. 

Earlier in the summer I was in Anchorage visiting a friend (Tom Doolittle—the first Naturalist hired by Lois Nestel at the Cable Natural History Museum). Mostly I was doing trip planning and homework, but I wanted to get some fresh air, too. Tom had been raving about the Upper Huffman Trailhead in Chugach State Park, on the hill just above town, so that's where I headed. 

The parking lot was completely empty—a far cry from the nearby Flattop Trail I’d hiked earlier that had a herd of people on it. 

I headed out on the trail. It was pretty wide and gravely, but tunneled through thick brush and shrubs. Tall grasses lined the trail, too. On some of the trees, I saw where moose had scraped the bark off during the winter.

I also noticed a couple piles of what might have been bear scat, and a couple piles of what was definitely bear scat! This time of year it’s very fibrous because of the plants they're eating. Moose scat is much better digested because of their four-parted ruminant stomachs.

All the while I hiked through this, every 5-10 seconds, I called out "Hey Bear! Hey yo!"

Then, as I was passing through an area that felt a little more open because it was just tall grasses near the trail, I heard what sounded like a tree falling back in a little grove of mountain hemlocks. If I was in Iowa, the sound could only have been a rotten tree or branch finally giving way. However, I'm in Alaska. I yelled “Hey Bear” more loudly, and tried to peer into the grove to see what was causing the noise.

A cow moose burst out of the grove and galloped through the grass toward the trail I was hiking! Well, with moose you're supposed to run away. So I jogged a few steps back the way I came. Luckily she angled away from me and disappeared around the corner to the left at a T-intersection up ahead. 

Few! That was a little close for comfort!

Now I had to decide what to do. I wanted to hike another couple miles. I figured that if she turned left at the T, I could probably turn right at the T and be ok. Before I could walk more than a few steps in that direction, the grass rustled again.

This time a BROWN BEAR burst out of the bushes! I started to grab for my bear spray, but he was loping away from me, following the exact path of the moose. He looked over his shoulder at me as I said “HEY BEAR” even louder (and maybe a little more shakily) than before, but he kept on going and disappeared around the corner. I stopped reaching for my bear spray, and grabbed my cell phone camera instead. I just had time to snap one quick photo.

It took me more than a month in Alaska to see a bear, and this was a pretty exciting encounter. 

It was a little too exciting for a solo hike, though. I turned around, went back to my car, and drove to a different trailhead. I was heartened because there were two other cars in the pull-off. I wouldn't be alone out there. 

This gravel trail was even wider, although the same thick brush closed in on both sides. “Hey Bear!” I was hiking up a slight hill, and pretty soon a group of six women and three dogs came hiking down the trail toward me. A bear would have no trouble hearing them! Heartened even more, I kept going. 

Then I came to an intersection. The SAME intersection where I had seen the bear and the moose disappear around the corner. I (and the ladies) had unknowingly hiked up the same trail the bear and moose had just run down. “Hey Bear!” It probably would have been fine to keep hiking, but the scenery among all those shrubs just didn't feel worth it anymore. Not by myself. “Hey Bear!” I was tempted to run after the group of friends and ask to tag along. 

Instead, I just turned around and “Hey Bear!” started hiking back to my car. “Hey Bear!”

Halfway back, I heard some hollow thuds in the brush, like something heavy on airy ground. “Hey Bear!” Then I saw a huge rack of antlers above the first row of shrubs. “Hey Moose!” My heart started racing again! Moose aren't predators, but they are said to be nearsighted, easily spooked, and need a wide personal bubble. They are also huge. “Hey Moose!”

He ran off diagonally across the trail between me and my car and disappeared surprisingly easily into the brush. “Hey Moose!”

I waited a minute, then cautiously walked to where he had crossed the trail. There was a definite path into the brush, and also heavily moose-browsed shrubs sticking up out of the grass. “Hey Bear!”

Once back at my car, I decided to return to the busy Flattop Trailhead and hike among humans for a few miles. I ended up having a fun chat with two girls from California—one is a teacher on summer break, the other is taking a leave of absence from her job. They were super excited about my recent wildlife sightings. Now that I was safe and with others, I was, too.

Emily is in Alaska for the summer! Follow the journey in this column, and see additional stories and photos on her blog:

For 50 years, the Cable Natural History Museum has served to connect you to the Northwoods. Come visit us in Cable, WI! Our new exhibit: “Bee Amazed!” is open.

Friday, August 17, 2018

Paddling Among Icebergs

After my spectacular hike up to the Harding Ice Field in Kenai Fjords National Park, I wanted to do more than just look down onto the complex world of glacial ice from high above. Through a friend from Northland College, I discovered that Adventure 60 North, a guide service in Seward, runs sea kayak trips to the toe of a calving glacier.

I was glad for my brand-new, bright green rain jacket as I boarded a water taxi the next morning in the cold, steady drizzle I’ve come to expect from Alaska. Back at the Adventure 60 North shop, our guides, Sunny and Nick, had outfitted us with dry bags for our stuff, and supplied any other gear we didn’t already own. After two-and-a-half months in Alaska, I was well-prepared with the ubiquitous brown Xtratuf boots, rain pants, and my cheerfully green jacket.

The water taxi ride itself was spectacularly filled with sea otters, orcas, two kinds of puffins, rocky cliffs and crags, sea lions, a bristle-thighed curlew, hot coffee, and good conversation. I’ll probably write more about all that later! For now, let’s focus on how cool it felt to be paddling in a kayak among bobbing chunks of glacial ice.

We glided through the maze of mini-bergs for a while, having landed on the gravely beach of a glacial moraine about two miles from the current glacial terminus to switch from one type of boat to another. Neoprene pogies—which are little hand pockets that Velcro around the paddle shaft—kept our hands warm despite the ice water. About a half-mile from the glacier’s front we paused and floated, admiring the huge, pale-blue tongue of ice that reached down out of the clouds and into the sea.

Suddenly, thunder rumbled. A little bubble of excitement rose up in my chest. I love thunderstorms, and I’ve missed them while in Alaska. This was even better. The ice itself was rumbling. We searched the blue cliff at the water’s edge for movement, but found none. The movement must have been farther up the glacier, or deep within. After a few moments, thunder rumbled again. This time we watched a chunk of ice tumble into the sea. A small white avalanche of crushed ice poured in behind it, and a wave spread out from the glacier. We gasped and cheered.

Glaciers are constantly moving, after all, that’s what makes them glaciers. During the hundreds of years that snow built up and compressed older snow beneath it, pressed out all the air bubbles, and caused the crystals to reform into dense ice, it wasn’t a glacier. Finally, when that huge mass of ice began to flow downhill or out toward its margins under its own weight, a glacier was born.

Aialik Glacier, the one we were scanning for action, moves forward two to four feet per day. Under pressure, ice can bend and flow. Near the glacier’s surface, however, the brittle ice must crack to accommodate the hidden topography below. A glacier’s speed is due to a combination of the ice’s thickness, the gradient of its valley, and the presence of water at its base. Add in the fact Aialik is a tidewater glacier that ends in warm, constantly fluctuating seawater, and you have a very dynamic system.

We studied the heavily crevassed surface of the glacier, and all made guesses about which section would go next. Sunny had explained that the spires of ice formed by intersecting crevasses were called seracs. Three out of the seven paddlers in our group pointed to the same, precarious-looking section. Minutes later, thunder rumbled and that heavily fractured serac splashed into the sea. After several minutes more, we bobbed on its wake.

Thunderous calving into the ocean was exciting, but I still wanted to get up close and personal with big icebergs. A few days later I filled the last spot on another kayak trip, this time with Anadyr Adventures in Valdez. This adventure skipped the water taxi and delivered us by van right to the shore of a little proglacial lake just outside of town. The Valdez Glacier had scoured a deep valley, dammed one end with a moraine, and melted back. Even though this lake wasn’t affected by tides like Aialik Glacier, water still lubricated turmoil at the toe.

Our morning at Valdez Glacier Lake began in thick fog. This canoe soon launched full of four grown men, two of whom carried huge camera lenses. Photo by Emily Stone.
We launched inflatable kayaks onto mirror-calm water in a dense fog. Huge icebergs loomed in the shallows. Someone made a joke about the Titanic, but that didn’t stop us from paddling up for a closer look. Most bergs were heaped with blankets and piles of wet, brown sediments, which indicated that they were floating upright, in the same orientation as when they’d been attached to the glacier. Where chunks had broken off to reveal their inner ice, though, the crystals were huge, sparkling, and made luminous patterns of white and blue.

Although our day began in thick fog, blue sky hovered above. Seeing the lake and icebergs in both lights was a fun part of the experience. Photo by Emily Stone
Up close, the broken and melting sides of the icebergs were a luminous blue. Our inflatable, sit-on-top, tandem kayaks felt very stable and maneuvered easily for a closer look. Photo by Emily Stone.
Glacial ice is dense, with very little air. As light passes through it, the wavelengths of red and yellow light are absorbed, and blue light is scattered and reflected back to our eyes. The deeper the light penetrates into the ice, the more blue it appears. Snow and ice with more air among their crystals scatter light back from their surface.

A few bergs were pure white, at least from a distance. Those had rolled over, exposing their cleaner core of ice (which gains air as they melt, making them white instead of blue), and dumping their sediment load into the lake. Today, the ice dripped placidly, melting bit by bit. Our guide, though, has watched these behemoths split, roll over, and shatter. As I ran my hand along the smooth, wet side of one berg, I was grateful for the contrasting lack of thunder on this adventure.

One of our group explored near two icebergs that have rolled over, exposing clean ice and dumping sediment into the lake. Behind the left hand iceberg you can see the deep canyon containing the Valdez Glacier. Photo by Emily Stone.
After lunch, the fog burned off and revealed a brilliant blue sky. We scrambled up a canyon wall to get a better look at the glacier itself. The brown and white striped river of ice flowed from around a corner and into view. At the terminus lay a jumble of broken, dirty ice chunks, in the process of detaching fully into the lake. With bright sun illuminating everything, the lake seemed small; in the fog, we might have been on an endless sea.
Valdez Glacier is a river of ice, with a healthy dose of rocks and gravel mixed in. It seems to flow relatively smoothly back in the canyon, but becomes unstable and breaks up as its terminus hits the lake it created. Photo by Emily Stone.
Ever since I discovered how to read the glaciated landscape of Northern Minnesota and Wisconsin, I’ve been fascinated by these massive forces of nature. Admiring them from afar, seeing them up close, paddling among icebergs, touching their ice…glaciers are even more amazing than I’d expected…and I’m not done exploring them!

Emily is in Alaska for the summer! Follow the journey in this column, and see additional stories and photos on her blog:

For 50 years, the Cable Natural History Museum has served to connect you to the Northwoods. Come visit us in Cable, WI! Our new exhibit: “Bee Amazed!” is open.