Logbook entries from the March-April cruise are available for download into Google Earth. Fly to the Bering Sea to see where it all happened. Download the logbook file and open in Google Earth
Tom Van Pelt, NPRB, was on board as a scientist and Bering Sea Project program manager.
All photos by Tom Van Pelt unless noted otherwise.
Francis Wiese, NPRB, was on board 17-21 March as a scientist and media liaison.
Deanna Wheeler, PolarTREC teacher-on-board, blogged for her students.
Video (right) by Rolf Gradinger.
Tom Van Pelt, aboard Healy, near Unalaska Island
We finished work at the last of about 40 scientific stations on 27 March and turned south, breaking heavy ice and moving slowly. The scientists got busy packing away all of the equipment in the labs, clearing room for the next cruise (HLY0902) which follows this one.
By Sunday, we were abreast of St. Matthew Island (right) and had left the heaviest ice behind. See larger image
We were still breaking ice in an area that had been totally ice-free on our way north, three short weeks ago -- illustrating how dynamic the ice cover can be in the northern Bering Sea. But by dawn on Monday morning, we were moving through big patches of open water, and by midmorning we had left the ice entirely.
Open ocean felt delightfully liberating after 17 days of breaking ice. The silence of our movement, slipping through the water at a speedy 16 knots, was almost startling, and the southerly swell gave the ship an unfamiliar but gentle up-and-down motion beneath our feet.
In earlier logbook entries, I've mentioned the important work done by the scientists on board who are studying the seafloor, or the "benthic zone." Why is their work important?
First, think about the seafloor as the marine "bottom line." All of the abundant life in the sea eventually dies and falls to the seabed. Any organic material that isn't consumed on its way down winds up in the benthic zone. The shallow continental shelf of the Bering Sea, which is only around 60m deep, features an exceptionally rich benthic zone. But how does the benthic zone function? What are the linkages between the benthic zone, the water column above it, and the ice? How do changing ice conditions affect it?
Second, we know that the seafloor in our study area support populations of predators that are of great interest to Native Alaskans and others in the region. The Pacific walrus and the spectacled eider, described earlier, depend heavily on the benthic zone for feeding. But how does this dependence operate -- what biological characteristics combine to make good seafloor feeding habitat for walrus and eiders? How do changing ice conditions affect those characteristics?
To tackle those important questions, the cruise has been organized around a series of scientific "stations" (right) where we collect samples. These stations are virtual points on the seafloor that Lee Cooper, Jackie Grebmeier, and others have been visiting in the context of various research programs for more than two decades.
One of the challenges for biologists working on ecosystem-wide questions is the enormous spatial scale that's part of our work. By visiting the same point on the seafloor in different years, using GPS to position the ship, we ensure that any changes we see in the ecology at that spot over time are real.
The benthic team is a 24/7 operation, led by Lee Cooper and also by Jackie Grebmeier while she was aboard the ship during the cruise's first ten days. The full team consists of:
On Friday I pulled on an orange flotation suit, steel-toed boots and a hardhat, and assisted the benthic team. The main tool for their work is the "van Veen grab" (below). This is a clamshell-style shovel that is weighted with lead bricks and lowered to the seafloor with its jaws held open.
As the grab touches the seafloor, the lock holding it open releases. When the command is given to reel it in, the cable tightens and pulls the jaws together. The jaws dig down into the seafloor a foot or so before they snap shut and the grab pops free of the bottom. A minute or so later, the grab breaks the surface of the water and we swing it aboard (left).
Team Benthos is a tough bunch, dealing with seawater and mud day and night, with air temperatures in the single or minus digits and with often with a hard wind blowing that makes their working area on the aft deck feel much colder. Everyone wears facemasks against the biting cold. The van Veen grab swings overhead; waiting hands guide it down onto a wooden frame over a wide, galvanized bucket. We open the jaws, releasing the dense, rich mud of the seafloor (right).
Time for the big soup spoons (left) -- not for lunch, but to scoop out all the mud from the grab. We also rinse the grab, using cold seawater piped through a chronically-freezing hose. Errant seawater hits the deck, hardening into slippery ice within seconds.
Next two people join in to carry the bucket over to a rack of strainers. The fine mesh of the strainers retains all of the animals living in the mud. It’s a cold job rinsing all of the mud away.
Finally the mud is gone and we have a quantitative sample of the animals living in and on the seafloor (right).
Repeat this process six or seven times, add in deployment of a couple other sampling systems (HAPS corer, multi-HAPS, bongo nets, optics and UV sensors ...), and you have a full station's worth of science!
Healy 0901 has been a great success:
This first cruise of the 2009 field season for the BEST-BSIERP Bering Sea Project aims to “connect the dots” between cruise components as I've described here. It also aims to connect with subsequent cruises and other pieces of the integrated Bering Sea Project, aiming to address the overarching question that shapes the Bering Sea Project: how does seasonal ice influence the ecology of the Bering Sea, and how will changes in sea ice affect the Bering Sea?
When Healy reaches Dutch Harbor, a new team will board the ship, ready for Healy cruise 0902, led by Chief Scientist Carin Ashjian and scheduled to start on 3 April. Healy 0902 will cover a broader study area, focused on the whole eastern Bering Sea shelf region, and will use a wide variety of tools to investigate the Bering Sea as it transitions from its winter ice-covered state to the spring phase, with no ice cover and with blooming phytoplankton populations.
Tom Van Pelt, aboard Healy, southeast of St. Lawrence Island
Yesterday the north winds kicked up even more, building to a steady 40 knots. Winds that exceed 30 knots or so ground the helicopter, so the walrus team had no chance to go to work today.
Chief Scientist Lee Cooper worked with Healy's officers to find a suitable ice floe for safe deployment of the on-ice team, led by Rolf Gradinger. Rolf and his colleagues, including Katrin Iken and Bodil Bluhm, together with graduate students Brenna McConnell and Jared Weeds, study ice algae and their relevance in the Bering Sea ecosystem.
As we crunch and crash our way through the Bering Sea ice, from time to time our progress is halted by ice that is too strong for us to break. Sometimes we back up and change course in response, but most of the time we simply "back and ram." The ship backs up a length or two, then gathers speed through the broken channel to smash into the stubborn ice with tremendous momentum, driven by 20,000 horsepower accelerating hundreds of tons of steel forward. Right: Healy ramming sea ice (Rolf Gradinger).
One of the crew members compared Healy ramming ice at 8 knots to "1,600 Toyota Camrys hitting a wall at 60mph."
While we’re backing up, the overturned ice chunks sometimes show a distinct brownish-green color, revealing ice algae. These algae are specialized phytoplankton adapted to grow within the spaces between ice crystals on the underside of sea ice.
On first glance, this seems like one of the more minor but fascinating details of complex ecosystems. But in fact, ice algae can be extremely important components of high-latitude marine ecology.
Converting nutrients and sunlight into growth, phytoplankton forms the foundation of marine life. In ice-covered waters, little sunlight penetrates into the water column, making growth difficult for phytoplankton in the water. Yet the ice algae, as close to sunlight as possible in their protected homes underneath the ice, are able to flourish.
In the permanently ice-covered central Arctic Ocean, an estimated 50% of total plant growth, or "primary productivity," comes from ice algae. Right: algae on the undersides of broken pieces of sea ice, with an inset closeup. (Francis Wiese) See larger image
So how important are ice algae in the seasonally ice-covered northern Bering Sea? That’s the question Rolf and his team aim to answer.
I've been helping out with the on-ice deployments, led by Rolf and graduate student Brenna McConnell, who direct a team of three or four volunteers like me.
After parking the ship against a strong, suitable ice floe, the deck crew cranes the steep, metal "brow" over the side -- our way onto the ice (right). Before we're allowed out, a Coast Guard swimmer and a gun-toting polar bear guard descend the brow and assess the ice safety. After getting the go-ahead, we send down several army-surplus toboggans filled with equipment. Down on the ice, we haul the toboggans a short distance away from the ship, looking for undisturbed ice.
As with a lot of biology fieldwork, the on-ice deployments involve a funny mix of high-tech instruments and old-fashioned grunt work. We use an ice auger -- basically a four-foot high giant drill bit a foot across, powered by a lawnmower engine with handles -- to drill several large holes in the often meter-thick ice.
Into one of the holes, we lower a "CTD," an instrument package that measures the temperature and salinity of the water column and gives us an oceanographic context to the ice work. It’s kind of like taking temperature and windspeed measurements at a biological study site on land. With a price tag of $14,000, we make sure the knots securing the CTD are well tied. Right: Brenna with the very expensive CTD. More about CTD casts from 2008
Next, it’s time for sediment traps. Rolf wants to work out how much of the ice algae falls down to the seafloor, where it could become food for the worms, snails, clams and other animals that live on and in the mud and sand. The ice auger roars into action again, this time to drill four side-by-side holes that create a long slot in the ice, smoothed out with a medieval-looking ice saw.
All of the drilling and sawing creates a lot of slush in the super-cold salt water; I'm assigned to get rid of the slush, using a giant straining ladle like you might find in a big kitchen. Kneeling there in my drysuit on this thin skin of ice capping 60 meters of the Bering Sea, with the Arctic wind whistling past a spot that is in constant motion and will soon melt away, gives me plenty to contemplate as I scoop slush over and over again. Right: Dorothy Childers contemplatively scoops slush.
Ten minutes later I've scooped out most of the slush, and I'm rewarded by the sight of clear, dark water. It looks almost gelatinous, as though it can’t decide whether to be a liquid or a solid. In fact, it’s super cold at one and half degrees below freezing -- salt water has a lower freezing point than fresh water.
Kneeling next to the rectangular hole in the ice, Rolf and Ivan Kuletz prepare a metal frame equipped with two tall bottles. Rolf fills the bottles with filtered seawater, and we lower them to 20 meters into the water. We prepare another pair of bottles that we lower down to ten meters, then anchor the lines holding the bottles, and leave them to passively capture any material sinking down from the ice. Left: Rolf and Ivan filling sediment trap tubes, preparing to deploy.
Several hours later, we recover the sediment traps, and in the lab, Rolf and his colleagues will use the material to work out how much organic material is transferred from the ice to the seafloor.
Next we break out the ice corer. This hollow, four-foot long tube is four inches across, tipped with razor-sharp bits. Yellow with an orange spiral, it looks like an exotic candy cane. Right: Rolf and Ivan coring ice.
Fortunately, we repaired our heavy-duty drill to power the corer. When it broke at the last station, we had to drill some fifteen cores by hand, the old-fashioned way; which got a little old after a half-dozen or so. The electric drill makes short work of the ice. We fire up the generator and seconds later, we've punched a hole in the ice. Out comes the corer, we detach the drill, open the corer's top, and out slides a perfectly cylindrical core of ice.
The algae live at the bottom of the core. Why? We take a temperature profile of the first core to answer that question. The temperature at the bottom five centimeters or so of the core is very close to water temperature, but falls quickly with increasing distance from the water. Only 15 or 20 centimeters away from the water up the meter-long ice core, the ice temperature approaches the below-freezing air temperatures -- lethal for plant growth.
We also scrape off the algae zone from the bottom of the first core, putting it into bottles filled with a special solution. We attach those bottles to a weighted line, dropping them down into the water at different depths for an “incubation experiment.” Like the sediment traps, we leave those bottles for several hours before recovering them for later analysis in the lab, which will tell Rolf about the primary productivity of these algae.
We repeat the coring process a half-dozen times at one spot on the floe, cutting up the cores into sections for lab analyses; then move out 30 or 40 meters or so to two secondary spots, taking a couple more cores. We also measure both incident light and snow depth, so that Rolf can scale his results by how much light reaches the algae. Above: Brenna and Dorothy meaure core length and ice temperature profile. Right: Brenna holds a cross-section of an ice core.
At a range of sites across the northern Bering Sea, Rolf and Brenna have now completed seven ice deployments, capturing data on ice algae presence, productivity, and transfer to the seafloor. With these data, they should be able to describe how ice algae behave across a range of ice depths, snow cover, and seawater characteristics. Rolf and graduate student Jared Weems are also using isotopic tracers to work out how much ice algae benthic and pelagic animals rely on compared to other kinds of phytoplankton.
As the winter ice cover of the Bering Sea changes in response to climate change, ice algae will change right along with it; Rolf's work allows us to put numbers on those changes, filling in an important piece of the Bering Sea ecosystem puzzle and strengthening our ability to understand the consequences of changing ice.
At the same time, the benthic team is taking measurements of life on and in the seafloor. We're also learning about walrus, seaducks and other benthic predators and zooplankton that graze on phytoplankton on this cruise. All of this information, combined with data from other cruises as well as shore-based work, feeds into other pieces of the overall BEST-BSIERP study so we can build integrated, top-to-bottom models of this complex Bering Sea ecosystem. More about sea ice from the 2008 cruise
Tom Van Pelt, aboard Healy, off St. Lawrence Island
Steady northern winds over the past few days, blowing up to 35 knots, created a "polynya" -- an area of open water, surrounded by ice -- to the south of St. Lawrence Island. Having accomplished most of our work in the heavier ice to the east, yesterday Chief Scientist Lee Cooper decided to head into the polynya to run a series of transects and stations, allowing us to characterize the animal life, oceanography, and seafloor characteristics of this important type of habitat. Above: Polynya southeast of St. Lawrence Island. (Craig Kasemodel/PolarTREC)
More open water means more seabirds and marine mammals. The past few days we’ve been in relatively solid ice; aside from spotting the occasional walrus, and futilely scanning the horizon for polar bears, the observing team has mostly been documenting the unsurprising fact that seabirds and marine mammals are rarely found in areas of thick, unbroken ice. So with the prospect of crossing more open water, the shipboard observers led by U.S. Fish and Wildlife biologist Kathy Kuletz, assisted by her son Ivan and me, have swung into more intense action.
Kathy and Ivan's dedication to scrutinizing the ice and water quickly paid off when they spotted more than a dozen Kittlitz's murrelets (below) yesterday, and several more today.
This rare species, currently under consideration for "threatened" listing under the federal Endangered Species Act, is a very unusual seabird. The bulk of the 20,000 or so remaining Kittlitz's murrelets are found in regions with a lot of tidewater glaciers, like Prince William Sound. Scientists aren't sure why, but these small birds seem to prefer icy habitat.
They're also known to occur in smaller numbers in the Bering Sea and even farther north to the Chukchi Sea, but, of course, we have scant documentation of their presence in the ice, given how few vessels break into these icebound waters.
Seeing them here now, among the open water leads and with very few other birds around (with the notable exception of the spectacled eiders that Jim Lovvorn is studying on this cruise), gives us a sense of discovery and also of curiosity -- what is it about this harsh habitat that attracts the little Kittlitz's murrelets?
All of the measurements that are being taken at every station -- including the abundance of zooplankton, which are important prey for Kittlitz's murrelets, as well as the characteristics of the water column (temperature, nutrients, salinity, phytoplankton abundance) that drive zooplankton populations -- should help us work out some clues as to why the ice murrelet chooses to spend time in this polynya.
Soon we'll be back in the heavier ice, which will give Rolf Gradinger a chance to rally his team of ice corers and slush scoopers for a sixth "ice station" off the ship --
I'll describe his work in my next blog.
Tom Van Pelt, aboard Healy, off St. Lawrence Island
We're now deep into the thick ice of the northern Bering Sea, about 64km south of St. Lawrence Island. A high-pressure weather system has been sitting in the region for days, giving us beautifully clear (and very cold) weather. Thin layers of scalloped and ridged snow cover the ice pack, stretching in unbroken whiteness from horizon to horizon. (walrus photo by Joel Garlich-Miller)
The ship's clocks are still set to Kodiak time; we've come far west since leaving Kodiak, so the sun rises late. Looking out this morning at 9:00 am, the surrounding ice has a deep blue pastel shade, meeting a horizon colored red and yellow as we rotate toward sunrise. (ice photo by Francis Wiese)
"Flight briefing on the bridge at oh-nine-thirty hours" is announced on the ships PA system -- the walrus team is preparing for lift-off. Up in the dawn's half-light on the bridge, a circle forms: USCG officers and crew, the walrus biologists Chad Jay and Tony Fischbach; Bill Springer, the helicopter pilot; and other support crew work through a checklist of pre-flight preparations. The operations chief, Commander Jeff Stewart, closes the briefing: "OK, let's fuel and traverse the helicopter at 1000, and pipe for flight quarters at 1015 for a 1030 launch."
Familiar around the world as a symbol of the mysterious Arctic, walrus are a particularly important cultural and subsistence resource for the Siberian Yu’pik peoples living on St. Lawrence Island and elsewhere along the Alaskan and Russian coasts surrounding the Bering Sea. Despite their importance, we still don't know much about walrus. One of our primary missions on this Healy cruise is to learn more about where walrus like to feed in the late winter, and then investigate what kind of food is available at their preferred areas compared to other areas.
Walrus eat clams, worms, and other animals living in and atop the seafloor mud and silt. A whole team of hard-working scientists is bringing up seafloor samples around the clock, working under brutally cold conditions on the aft deck to investigate the life living in and on the seafloor. Go to the ice algae blog
Wriggling into a tight-fitting drysuit and strapping on a pack filled with crossbow bolts and arctic survival gear is part of the unique daily routine that Chad and Tony follow on board Healy. Since the ship has been in the ice, each day they load up and fly out in the helicopter, looking for small groups of walrus. When they find a group that offers a safe downwind approach with strong ice that will support the weight of the loaded helicopter, pilot Bill Springer brings the chopper down, and Chad and Tony hop out to gather their gear.
Right: Chad Jay and Tony Fischbach, dressed for another day at the office. (Andrew Trites)
Dressed in white from head to toe, the biologists carefully approach the walrus. They scramble over precarious ice floes, and crawl belly down across flat expanses of thin ice to sneak in close enough to deploy the satellite-relayed-radios by crossbow: for them “close enough” means 10 meters or less. When they are in position to target the flat upper back of an adult walrus they fire a special crossbow bolt, with a sharp end that is essentially a tiny, razor-sharp harpoon, attached to a puck-shaped satellite transmitter. The harpoon anchors the transmitter on the walrus, resulting in a satellite-tagged walrus with no need for sedation or capture of these enormous (up to one ton!) animals.
Last year, on Healy cruise 0801, Chad and Tony attached satellite tags to ten walrus, allowing them to put together detailed information on where and when walrus feed. This year, they want to increase their sample size by attaching more tags.
So far on the cruise, Chad and Tony have had good luck -- they have more than a dozen "happy customers," as Tony puts it -- walrus that will now transmit their daily secrets of feeding and resting locales. In the coming months, Chad and Tony will receive daily “diaries” of the feeding and resting habits from these walrus along with location data. Combined with the information on benthic habitat and other oceanographic characteristics that scientists on this and other cruises are collecting, Chad and Tony will deepen their understanding of these enigmatic beasts, and other parts of the integrated BEST-BSIERP Bering Sea Project will benefit as we seek to understand how the Bering Sea ecosystem responds to changing ice conditions. More about walrus from 2008 fieldwork
Francis Wiese, aboard Healy, off St. Lawrence Island
It is calm, warm (-13C) and stunningly, serenely beautiful, the sun just rising over this virgin seascape. Yesterday the media all went out on a reconnaissance flight with Jim Lovvorn, looking for spectacled eiders.
They found about 10,000, and later a flock of 5,000 flew by the ship just as the sun was setting -- such synchronized harmony in the air.
Right: Spectacled eiders in an open lead off St. Lawrence Island. (Flock of eiders, Deanna Wheeler/PolarTREC; inset photo, Brendan Smith/NPRB)
I just spent four hours on the ice about 96km south of St.Lawrence Island. It is an incredible place, you stand on one meter of ice and snow over 70m of ocean, you walk on snow never walked on before or ever again, a place shaped by winds and currents, a system for itself, responsible for much of the rich life that lives at the bottom of the ocean.
Today, the drill that helps Rolf Gradinger drill ice cores broke, so Ivan (a young guy assisting with counting birds) and I drilled all the ice cores by hand, the good old fashioned way. It was good exercise and kept us nice and warm. The weather was perfect, hardly any wind, -13C, sunny ... We're now on our way to the next station to take more samples of plankton, water, and all the critters that live in the mud below. Right: taking ice cores. (Francis Wiese)
While Rolf and his team where on the ice, others went in search of eiders. So far, walrus biologists Chad Jay and Tony Fishbach have tagged thirteen animals. Once we head further east, they'll attempt to deploy the remaining six satellite tags. More about sea ice from the 2008 cruise
I've been on the ship now for 24 hours and just got done helping with the work we started at 3am today, taking samples from the bottom of the ocean. It was cold (-20C) but absolutely clear. With no light in the way, the stars overhead were overwhelming. Then back to grabbing mud from the bottom time after time. Around 5am, a male walrus suddenly appeared out of the darkness into the spotlight right behind the icebreaker. He was beautiful, puffed up, with big tusks. He hung out for about 15 minutes, played around with some ice floes and then disappeared.
It is an interesting group of people on board, from China, Norway, Chile, Germany, Canada, as well as the US. Breaking ice with a ship is rather amazing. It's loud against the hull, scraping like a metal junk yard crushing cars, outside the ice and snow sounds like styrofoam being brushed and torn apart. Everything on deck freezes and seizes, so we spend a lot of time staying warm and hosing down the equipment with warm water to keep it functioning when it goes into the water.
Quite some insights into how this extreme science is and can be done -- like they say in the POLAR-PALOOZA climate change rap -- by polar adventurers! Right: Scientists collect sea ice data. (Francis Wiese)
Tom Van Pelt, aboard Healy, heading north
Thirty-six hours ago, we departed Kodiak under low grey skies and cold drizzle. Over the ship's PA system came the terse warning: "Prepare to rock the shafts!" Before the ship's crew casts her lines loose, the officers on the bridge ask to see the massive propeller shafts in motion -- the engineers give the propellers a little bump, and on the bridge the watches observe the shaft rotation on a video monitor -- giving assurance that the ship will respond to commands after she's loosed from the pier. Above: Healy at the dock, pre-departure.
A few minutes later, lines were cast off, and with a little help from a tugboat, all 428 feet of the USCG icebreaker Healy slipped away from Kodiak and began to gather speed for the voyage around the Alaska Peninsula and through Unimak Pass, headed north to the Bering Sea ice.
This cruise -- "Healy 0901" -- is the first of several major research cruises that form the backbone of the BEST-BSIERP Bering Sea Project. Led by Chief Scientist Lee Cooper, thirty-seven scientists are busy making preparations for the work ahead. This cruise has several linked objectives, all built around hypotheses related to the interaction between ice cover and the marine ecosystem.
Now at 0230 on March 12, we're passing through Unimak Pass, nosing into a gentle swell as we enter the Bering Sea. The ship steams northward, commanded by Captain Fred Sommer, leading seventy-seven officers and crew. To the west, the Krenitzin Islands are visible in the bright moonlight, marking the start of the Aleutian Chain. To the east, the navigational light at Cape Sarichef winks out its faint signal. All of the months of meetings, planning, packing ... all of the grunt work that lives behind the scenes of this research cruise, such as bringing 15,000 pounds of gear aboard. Now all of the preparation is behind us and we're reaching the short window of intense action that lies a day or so ahead, when we reach the Bering Sea ice-edge.