Covering an area nearly the size of Texas, the Chukchi Sea lies off of Alaska’s northwest coast. It is considered part of the Arctic Ocean and is connected in the south to the Bering Sea by the Bering Strait. The increased focus on offshore drilling in the Arctic, and the unknowns that this kind of activity will bring to the region, are causing the Chukchi Sea to get a lot of attention these days. UAF researchers are at the heart of some of the biggest data gathering and documentation efforts the area has ever seen.

In early 2008, nearly three million acres in the Chukchi were leased to oil companies for potential offshore oil drilling, making oil activities a realistic possibility in the region. As a result, federal agencies and oil companies have provided millions of dollars in research funding for scientists to study the oceanography and animal life of the area.

Scientists at the School of Fisheries and Ocean Sciences have secured much of this funding, and their research extends from the currents at the ocean’s surface to the tiny animals that live in the soft sediment at the bottom of the Chukchi Sea.

Surface currents and oceanography
An important part of the research in the Chukchi is looking at the way the sea’s surface currents move in relation to the water beneath the surface.

Tom Weingartner and a team of scientists at the UAF School of Fisheries and Ocean Sciences have installed high-frequency radar transmitters on the shore of the Chukchi. The transmitters send signals over the water’s surface that are reflected off of the waves and received by shore antennae. The reflected signals are then transmitted to Weingartner’s team at UAF and processed to estimate the speed and direction of the surface currents.

According to Weingartner, the speed and direction of the surface currents could help determine the trajectory of an oil spill, help researchers understand the marine ecology of the area and assist in search and rescue efforts if necessary.

To see what’s happening beneath the upper few feet of the Chukchi’s surface, Weingartner has also deployed moored devices that sit on the ocean floor and provide measurements of everything from currents and temperature to salinity and sea ice thickness.

In addition to the moored instruments, SFOS oceanographer Peter Winsor has deployed two autonomous underwater vehicles, called gliders, to collect more data about what is happening beneath the Chukchi’s surface.

Each glider is about 5 feet long and flies like an airplane through the water in an up-and-down motion. It is propelled using an internal bladder that works much like a fish’s swim bladder. When the bladder expands, the glider moves toward the surface. When it contracts, it moves toward the seafloor.
The gliders move at a speed of nearly 1 mile per hour and can operate for up to three months. According to Winsor, the gliders can cover thousands of miles of ocean. At the surface, the glider transmits data, including its location and oceanographic readings, like water temperature and salinity, via satellite directly to scientists.

“The gliders swim under the radar mask. They transform the two-dimensional view of the ocean into a three-dimensional view,” said Winsor. “These projects are the first ever simultaneous high-resolution look at currents and stratification in the Chukchi Sea.”

Measuring water quality
A group of scientists led by Stephen Jewett, research professor of marine biology, is looking at water quality and potential contaminants in the nearshore waters of the Chukchi Sea. Last August, the team collected water and animal tissue samples from 31 sites along the coast from Point Hope to Icy Cape. Next year, the team will sample from Icy Cape to Barrow.

These samples are being tested for pollutants and water quality, and according to Jewett, will provide a baseline for the Environmental Protection Agency to test against in coming years. The water quality research was part of the Alaska Monitoring Assessment Program, which is funded by the Alaska Department of Environmental Conservation.

Fish in the Chukchi Sea
An understanding of the Chukchi Sea would not be complete without an understanding of the animals that live there.

Brenda Norcross is a fisheries oceanographer and arctic fish expert, and has multiple projects in the Chukchi Sea.

“Working in the Chukchi Sea is really, really exciting,” says Norcross, “because often not much has been done in this area before.”

She says that the current amount of knowledge about bottom-dwelling fish in the region is deficient, and that information about fishes that live in the water column is almost non-existent. She hopes to remedy this by providing baseline information about fish distribution, ecology and feeding in the context of both climate change and the potential for oil and gas exploration in the area.

One of Norcross’ sampling methods includes using a net about 10 feet wide and made of tiny mesh to pull sets of fish, crabs, starfish and other creatures out of the icy Chukchi waters. As a fish specialist, Norcross only needs the fish in the trawl for her study. Samples of the epibenthic animals — crabs and starfish and other organisms — go to epibenthic experts, while other samples go to their respective specialists.

Studying plankton
Another UAF researcher working in the region is Russ Hopcroft, a biological oceanographer, who is looking at what zooplankton and phytoplankton inhabit the Chukchi Sea. The phytoplankton, which are tiny algae that float in the ocean, are prey for the zooplankton, which in turn are prey for larger animals like fish, seabirds and whales.

To assess the amount and type of phytoplankton in the water, while at sea, Hopcroft deploys an oceanographic tool called a conductivity-temperature-depth profiler. The CTD profiler is cast over the side of the ship and provides a variety of data about the oceanography of the region. To collect zooplankton samples, Hopcroft uses a plankton net to filter out the tiny organisms at their sampling sites.

Hopcroft says that it’s important to “get a concept of how unique or how vulnerable” the region may be to human impacts before any activities occur.

Looking at the seafloor
Marine biologist Brenda Konar is studying organisms such as sea stars and sea anemones that live on the Chukchi’s seafloor. Her project is part of the Chukchi Sea Offshore Monitoring in Drilling Area Chemistry and Benthos (COMIDA-CAB) program. The program is funded by the federal Bureau of Ocean Energy Management, Regulation and Enforcement and was created to establish an integrated look at the Chukchi region’s ecosystem.

Konar herself is interested in not only what animals live on the Chukchi seafloor, but also in how the species are distributed, what species are dominating in particular areas, and what processes are driving the way these plant and animal communities look.

“I want to find out what is structuring these communities,” says Konar. “There is a suite of players, some more dominant than others. In one station, it took just a minute and a half for the 3-meter long trawl net to completely fill with sand dollars.”

While Konar is looking at the organisms that live on the surface of the seafloor, Arny Blanchard, a marine invertebrate expert, is studying the animals that live in the soft sediment on the Chukchi seafloor. These animals include marine invertebrates like sea worms, shrimps, snails and clams.

The creatures that live in soft sediments on the seafloor are excellent indicators of environmental conditions and often are the first to show the effects of human activity. According to Blanchard, these bottom-dwelling organisms are critical to the ecosystem because they provide food for other animals, like other marine invertebrates, fish and marine mammals.

Blanchard says that long-term monitoring of the health of the invertebrate community is a “necessary step in understanding and protecting the environment where human impacts are planned.”
Into the future

Next year, most of the SFOS scientists researching the Chukchi Sea will return to the area to collect more samples and conduct more measurements as they continue to develop baseline information about the Chukchi Sea and the animals that live there. Much of this baseline information will provide entirely new knowledge about the Chukchi and will help scientists and public leaders determine the potential impact of human activities.