The Blog Aquatic » conservation http://blog.oceanconservancy.org News, opinions, photos and facts from Ocean Conservancy Thu, 28 Aug 2014 17:32:30 +0000 en-US hourly 1 http://wordpress.org/?v=3.4.2 Ocean Acidification Wrecks Sharks’ Smellovision http://blog.oceanconservancy.org/2014/08/20/ocean-acidification-wrecks-sharks-smellovision/ http://blog.oceanconservancy.org/2014/08/20/ocean-acidification-wrecks-sharks-smellovision/#comments Wed, 20 Aug 2014 21:06:23 +0000 Sarah Cooley http://blog.oceanconservancy.org/?p=9054

Scarier than any movie shark that can smell a drop of blood miles away (they can’t, by the way) is this week’s news about sharks’ sense of smell. A team of Australian and American scientists has just shown that smooth dogfishes (also called dusky smooth-hound sharks) can’t smell food as well after living in ocean acidification conditions expected for the year 2100. These “future” sharks could correctly track food smells only 15% of the time, compared to a 60% accuracy rate for unexposed sharks.  In fact, the acidification-exposed sharks even avoided food smells!

This surprising result is also pretty sobering, when you consider how important sharks’ sense of smell is to nearly everything they do. Sharks have especially large, complex “nose” organs, which help them find food, mates, and predators, as well as find their way around the oceans. Many sharks, including the smooth dogfish, are very active at night and in the deep, dark ocean, so their sense of smell provides critical information about their surroundings. The researchers note that the sharks’ damaged sense of smell is probably due to the same changes in neurotransmitters reported in coral reef clownfish (yes, Nemo) that love the smell of predators in an acidifying ocean.

Despite their mighty reputation, sharks are under threat from overfishing, pollution, and habitat loss. Sharks that also can’t find food or avoid predators will probably not survive long, causing even more trouble for shark populations. They grow and reproduce slowly, too, meaning that sharks that die young aren’t replaced quickly. Scientists still don’t know yet if the smooth dogfish can adapt over several generations to improve their odds against the ocean acidification we will see over the coming decades, but it doesn’t look good.

Smooth dogfishes live along coasts from Maine to Florida, around the Gulf of Mexico and the Caribbean, and along the southeastern coast of South America. They might benefit somewhat from the actions that East Coast states like Maine and Maryland are taking against ocean acidification, but as species that migrate long distances, our best bet is to cut carbon dioxide emissions globally.

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How Do We Restore the Gulf Beyond the Shore? http://blog.oceanconservancy.org/2014/08/18/how-do-we-restore-the-gulf-beyond-the-shore/ http://blog.oceanconservancy.org/2014/08/18/how-do-we-restore-the-gulf-beyond-the-shore/#comments Mon, 18 Aug 2014 20:19:54 +0000 Libby Fetherston http://blog.oceanconservancy.org/?p=9034

In the wake of the BP Deepwater Horizon oil disaster, everyone’s talking about how we restore the Gulf Coast. But the Gulf of Mexico is more than what we can see from the shoreline. If we restore the coast without restoring the deep waters, we’re only addressing half the problem.

That’s why Ocean Conservancy has created Restoring the Gulf Beyond the Shore. It’s a short guide to the wildlife that lives in the Gulf’s waters and it explains why it is so important that we ensure the health and safety of our fish, dolphins, seabirds, and whales (yes, whales in the Gulf!).

With over 15,000 species that call these waters home, and dozens of migratory visitors – Atlantic bluefin tuna, sperm whales and northern gannets, to name a few of my favorites – the Gulf plays host to incredible creatures and complex dynamics connecting land and sea. Even before the BP oil disaster, the Gulf was struggling under the weight of dead zones, overfishing, coastal habitat loss and more. With much of this damage underwater and out of sight, restoration becomes even more difficult to define, because we must imagine what we cannot directly see and estimate what we cannot directly count.

Along the coastline, restoration is defined as replacing something that has been damaged. It is a tangible process that creates new oyster beds, marshes and barrier islands. Beyond where the eye can see, however, restoration must take a different shape. Restoring deep-water species and habitats means gathering knowledge through science and technology that we can then use to reduce human impacts and other sources of stress and give marine species the best opportunity to recover on their own. This approach is known as natural recovery and there are few other ways to restore fish, dolphins, turtles or deep-sea corals.

In an era of shrinking budgets, science and knowledge have been something of a luxury in the Gulf. And now restoration funds resulting from this disaster offer an unprecedented opportunity to repair what was damaged, fix chronic problems and enhance what remains. The decisions we make now will impact the region for decades to come, and the only question that remains is: how do we invest in successful and strategic restoration projects and processes that restore the Gulf, on which so much depends?

The long answer? Restoration must be comprehensive: from the rivers that feed the estuaries, to the deepest expanses of the seafloor, where the BP oil disaster began, to the communities that call the Gulf Coast home. We must make smart and immediate investments that address pressing needs in the Gulf, as well as foundational projects that support ongoing and future restoration efforts. If we are going to use this once-in-a-lifetime opportunity to protect and enhance the Gulf and its unique culture, we must ensure that restoration of the marine environment is an integral part of our approach.

The short answer? Let’s make those decisions count.

Want to make a difference for the Gulf? Tell our Gulf leaders to include marine restoration projects as an essential component of Gulf restoration.

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Sight and Smell: How Traditional Methods Won’t Hold up Against Ocean Acidification http://blog.oceanconservancy.org/2014/07/25/sight-and-smell-how-traditional-methods-wont-hold-up-against-ocean-acidification/ http://blog.oceanconservancy.org/2014/07/25/sight-and-smell-how-traditional-methods-wont-hold-up-against-ocean-acidification/#comments Fri, 25 Jul 2014 12:13:06 +0000 Alexis Valauri-Orton http://blog.oceanconservancy.org/?p=8819

Ocean acidification is invisible to the naked eye.  It’s not something we can smell, not something we can feel with our fingers.  But in many parts of the world, that’s just how fishermen and shellfish farmers assess the water they work in.

Right now, the methods we have to understand and respond to ocean acidification are expensive, requiring a lot of equipment.  For example, oyster farmers in the Pacific Northwest rely on ocean monitoring systems that tell them the condition of the water, high-tech hatcheries that give them a controlled environment in which to rear their oysters, and buffering systems that allow them to neutralize the water coming in and make it suitable for oyster growth.

For shellfish farmers who are worried about making a profit at the end of the day, it can be impossible to foot the bill for expensive technologies like these.  That’s where government support comes in. The oyster farmers of Oregon and Washington State were able to build their defenses against ocean acidification with help from the federal government, which directed half a million dollars to the development of these monitoring and adaptation systems.

In many places I visited, however, government support was limited and these important technologies were nowhere to be found.

In Ban Don Bay, the hub of shellfish farming in Thailand, I sat on a wooden long-tail boat at peak clam harvesting hours: 1 – 4 am.  Why the middle of the night?  Because that’s when the tide is low enough to dredge the mud flats by hand.  A young man single-handedly hauled a steel cage up onto the boat, dumping out the clams that had been dredged from the farmed-flats below.  He threw the empty cage overboard, while an older man steered the boat ahead.  The cage dragged along the bottom for a few minutes until the young man tugged on the rope again to haul the harvests on board.

Thousands of shellfish farmers work the mudflats of Ban Don Bay.  But they rely entirely on natural seed, having no hatchery to supply them.  Many farmers told me of how they had observed changes in the water—an increase in algal blooms, changes in the smell and color of the water—but they didn’t understand these changes, and had no way of knowing what caused them. Jintana Nugranad, a Senior Fisheries Biologist working within the Thai Government, told me of how she had fought to maintain a shellfish hatchery and expand monitoring efforts to support the industry in Thailand through scientific research on shellfish and seed production, but received no support in her efforts.

This was the case for much of the scallop industry in Peru as well.  Farmers collect natural seed from an island near Sechura Bay.  There are a few privately-operated hatcheries in the bay, but so far none of them have equipment to monitor the chemistry of their intake water, or to modify the chemistry of that water if it proves too acidic for their scallops to grow.  Scallop farmers were hopeful, however, that the government and private sector would support the development of hatcheries throughout the country.

In Hong Kong, oyster farmers told me how they hope for similar support from their government.  They work in Lau Fau Shan, in the Northwest corner of Hong Kong’s New Territories.  The region is famous for its oysters, and the only place in Hong Kong where oysters are still grown.  One of the farmers, Mr. Chan, explained to me that the hyper-capitalist structure of Hong Kong means there is little support or services provided for primary industries like his.  He pointed to China, just across the bay, and told me of how shellfish farmers there receive government support to invest in advanced technology.  But in Hong Kong, he told me, “e He pointed  The way we farm oysters is very backwards. We rely on traditional knowledge that has been handed down for maybe 2,000 years.  It is not scientifically advanced.”  He told me of how they use the moon to time their farming activities and smell the water to determine its quality.

Time and again, Mr. Chan told me of how he wished to have access to more advanced technologies.  “Can you help me?” he asked.  “Can you teach us what they do in America?”

Given how many environmental pressures these shellfish farmers face, ranging from industrial and agricultural runoff to changes in temperature and frequency of algal blooms, it’s remarkable that they have been able to survive in the industry.  But ocean acidification is a powerful and complex threat.  It cannot be seen without the help of technology, and it affects every drop of water surrounding these shellfish.  Without access to monitoring equipment to determine what is happening and where, and with limited resources and access to technology that may allow for adaptation, it will be very difficult for these shellfish industries to survive.

It is therefore critical that we expand research efforts to improve our understanding of ocean acidification as well as our methods for addressing it.  This is exactly what NOAA’s Ocean Acidification Program is doing, but the program needs more funding to accomplish its goals.  Support our petition to increase funding for NOAA’s Ocean Acidification Program.

A man dumps a bucket of water over clams he has just dredged from the bottom of Ban Don Bay, in Thailand.  He harvests when the tide is lowest—in this case, in the middle of the night. Bamboo stakes mark the edge of shellfish farming beds in Ban Don Bay.  Some farmers sleep in wooden stilt houses at night. An oyster farmer from Surat Thani, home of Ban Don Bay, shows off his prize for having the highest quality of oysters in the region. A man and his wife smile as they sell their oysters at the local market near Ban Don Bay Juan is the manager of one of Peru’s only scallop hatcheries.  He doesn’t have the equipment to take high quality pH measurements in his hatchery. Mr. Chan pulls a string of oysters up from his bamboo rafts in Deep Bay, between Hong Kong and China. A man returns from harvesting oysters in Deep Bay. ]]>
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Fishermen and Scientists Work Together to Track Sick Fish http://blog.oceanconservancy.org/2014/07/21/fishermen-and-scientists-work-together-to-track-sick-fish/ http://blog.oceanconservancy.org/2014/07/21/fishermen-and-scientists-work-together-to-track-sick-fish/#comments Mon, 21 Jul 2014 14:22:59 +0000 Alexis Baldera http://blog.oceanconservancy.org/?p=8776

University of South Florida Professor Steven Murawski began studying diseases in fin fishes after the 2010 Deepwater Horizon oil spill when Gulf of Mexico fishermen began reporting a surge in fish with visible lesions. Credit: C-Image. Caption from phys.org

Fishermen are on the water every day, which means they are often the first to notice when something changes. After the BP Deepwater Horizon oil disaster, we heard reports from fishermen that they were catching more fish with lesions than they had ever seen before. Immediately after hearing these reports, Dr. Jim Cowan at LSU began investigating the frequency, location and cause of the reported lesions. Many other scientists have collected data on this same issue, and last week a group from the University of South Florida published the first round of results in a scientific journal.

Through extensive study, the scientists ruled out other potential causes, such as pathogens or oceanographic conditions, and concluded that the BP oil disaster is the likely cause of the fish lesions. Oil has a distinct chemical signature that allows scientists to differentiate between different origins, and contamination in the sick fish was a better match to oil from BP’s Macondo well than any other source.

For the Gulf, studies that help us understand the lingering impacts of the BP oil disaster are critical to achieving recovery. They are also a reminder that we cannot close the door on studying the effects of the disaster or the impact of our restoration efforts until we are certain the job is complete. The results of the USF study are only the beginning of this story about how fish were impacted by the BP oil disaster. In order to achieve complete recovery, we need long-term research on how lesions and other oil impacts affect the survival and reproduction of fish, how their populations are responding to habitat and water quality restoration efforts, and what that means for the fishermen who first identified the problem.

Location of sampling stations and the percent of skin lesions per station for June–August 2011. The percent of skin lesions at a station is indicated as follows: white circles = 0%, red graduated circles = 0.1–2.0%, 2.1–4.0%, 4.1–6.0%, and >6.0% (from smallest to largest). The gray shading is the cumulative distribution of surface oil occurring during the duration of the Deepwater Horizon (DWH) event. Map credit: Murawski et al., 2014

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The Ground Beneath Their Feet: The Threat of Ocean Acidification to a Small Island http://blog.oceanconservancy.org/2014/07/10/the-ground-beneath-their-feet-the-threat-of-ocean-acidification-to-a-small-island/ http://blog.oceanconservancy.org/2014/07/10/the-ground-beneath-their-feet-the-threat-of-ocean-acidification-to-a-small-island/#comments Thu, 10 Jul 2014 23:18:04 +0000 Alexis Valauri-Orton http://blog.oceanconservancy.org/?p=8723

What if the ground beneath your feet, the very foundation of your life and livelihood, was at risk of eroding away?  What if the very thing from which you and your community draw 95% of your wealth was at risk of disappearing?

This is the reality that Aitutaki, a small island in the Cook Islands, and many other small islands around the world, are facing.  Aitutaki, and its stunning lagoon, is protected by a coral reef.  Powerful ocean waves crash on the edges of the reef, but because coral reduces wave strength by 97%, the lagoon and the coral sand beaches remain still and calm.  The value of this protection, and the environment it creates, cannot be overstated.

I spent seven weeks in the Cook Islands as part of my Watson Fellowship studying how ocean acidification might affect communities, and for six of those weeks I called the 6.5 mi2 island with 1,800 residents home. During that visit, I saw not only how delicate the island’s ecosystem is in the face of global stressors like climate change and ocean acidification, but also the value of the thriving economy and society built squarely on its coral.

The skeletons of coral are made of calcium carbonate—the same substance that forms the shells of oysters, mussels and clams.  As the ocean becomes more acidic, it becomes more difficult for coral and shellfish to form the calcium carbonate they need. Eventually, coral won’t be able to rebuild its skeleton as quickly as it is broken down.  Recent studies show that by mid-century, a majority of coral around the world will have trouble building their skeletons.

If the coral protecting Aitutaki is damaged by ocean acidification, or rising sea temperatures, the whole island is at risk.  The coral not only protects the island from waves and storms, it also creates the spectacular lagoon and marine habitat that supports the island’s dominant economy: tourism.

An officer in the Cook Islands Ministry of Tourism told me that he believes tourism accounts for 95% of his country’s GDP.  Just like the scallops in Sechura, the economy based on coral and the lagoon extends beyond the water to an entire hospitality industry, ranging from food services to transport to lodging.  And just like in Sechura, the economic boon created by marine resources creates immense opportunities and growth for local communities and families.  Before tourism, the people of Aitutaki lived off the land and sea.  The influx of money from tourism has created a whole new way of life; one in which food is flown in to this remote island from around the world, where islanders go abroad for education, and where traditional knowledge of subsistence living has all but disappeared.

Minister of Marine Resources for the Cook Islands, Teina Bishop, explained the predicament of this new economy very plainly. “Tourism is our industry, and the pillars of tourism are our environment and our culture.  If the coral goes away, we lose tourism.  If we lose tourism, we lose income, and people will leave.”

Yes, tourism now dominates the economy of Aitutaki and allows islanders more than just a subsistence livelihood.  But ocean acidification and rising sea temperatures, the very stresses that threaten the tourism industry, would also damage the island and the ability of islanders to return to a subsistence livelihood. That means it’s just not the current way of life on Aitutaki that is threatened, it is all life.  It is their home that is threatened.

And that’s what struck me.  Ocean acidification could impact all life on small islands around the world—islands that, like Aitutaki, depend on coral for the very ground beneath their feet.  But that doesn’t have to be Aitutaki’s reality.  When I asked the Mayor of Aitutaki, John Baxter, about the future, he said, “I am hopeful.” There is momentum around the world to reduce carbon pollution—the main cause of ocean acidification—and cutting-edge research is being done to better understand how corals respond to changing oceans.  But more needs to be done, and we all need to do our part.  In the United States, you can support increased funding for science by signing our petition to Congress.  Research efforts here can lend important information to islands like Aitutaki, and help give Mayor Baxter a reason to be hopeful.

Chunks of coral skeleton line the northern beaches of Aitutaki.  Over time, these skeletons break down and form the fine sand that fills the lagoon and delights tourists. An aerial photo I snapped on my way into Aitutaki shows how the brilliant turquoise of the lagoon dramatically shifts to a deep ocean blue, right where the coral drops off. Large waves crash on the edges of the coral reef, only a few hundred feet off shore. Tourists spent up to $10,000 to come to Aitutaki for the chance to catch and release the mighty bonefish, as these men are doing here. Tourists disembark a lagoon cruise that has just arrived at one of the islets within Aitutaki’s lagoon. Destination weddings are a large source of income for Aitutaki.  Here, Bishop Cruises (owned by Minister of Marine Resources, Teina Bishop), has assembled a marriage arch on the stunning beach of One Foot island. The shores of this islet, called Honeymoon Island, could erode quickly if strong waves reached them. Louis, Mike and Cruise play traditional island songs for the patrons on the Bishops Cruise to One Foot Island. Puna has been leading lagoon cruises for 20 years, and hopes the lagoon will stay healthy enough to support his children and grandchildren. A young girl performs island dances for a crowd at a beach restaurant. Islanders line up outside of the Cook Islands Christian Church on ANZAC Day.  What may be a week-long visit in paradise to some is a home with a rich history to others. Teina Bishop, Minister of Marine Resources, is working with his office to enact local measures that will protect coral. My host mother, Eikura, wades in the lagoon in the pouring rain, setting a net to catch our dinner.  She told me of how much has changed about her home since tourism took over the economy, saying that the young people simply don’t know how to fish and farm like she did as a child. Louis, one of the entertainers on the Bishops Cruise, introduced me to his young niece.  Islanders are worried that the youngest generation won’t know how to return to a subsistence living if tourism can no longer support their economy. John Baxter, the mayor of Aitutaki, poses next to the truck of his family’s business.  He is hopeful that Aitutaki will remain strong, despite the growing challenges the island and its ecosystem face. ]]>
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How We Can Respond to Increased Shipping in the Bering Strait http://blog.oceanconservancy.org/2014/05/28/how-we-can-respond-to-increased-shipping-in-the-bering-strait/ http://blog.oceanconservancy.org/2014/05/28/how-we-can-respond-to-increased-shipping-in-the-bering-strait/#comments Wed, 28 May 2014 12:50:56 +0000 Andrew Hartsig http://blog.oceanconservancy.org/?p=8407 Recent posts on The Blog Aquatic have focused on the Bering Strait: the 50-mile-wide gateway that separates Alaska from Russia, and that provides the only marine passage between the North Pacific and the Arctic oceans.

Two weeks ago, we highlighted the extraordinary abundance of wildlife that migrates through the Bering Strait each spring—from bowhead whales and ice-dependent seals to walruses and seabirds. We also emphasized the importance of the region’s highly productive marine ecosystem to the residents of coastal communities who rely on marine resources to support their subsistence way of life and cultural traditions.

Last week’s blog entry described how the retreat of seasonal sea ice in the Arctic has facilitated the steady growth of vessel traffic through the Bering Strait. We noted that these additional ship transits will cause more air, water and noise pollution; elevate the risk of ship strikes and the potential for introduction of invasive species; and increase the odds of major spills that could have catastrophic effects on the ecosystem. And we described how the Bering Strait’s harsh environmental conditions, remoteness, and lack of infrastructure combine to increase operational risks and create enormous challenges for those who would respond to accidents in the region.

How should we respond to these threats?

We can take one option off the table right away: closing the Bering Strait to vessel traffic is not a viable approach. Under the United Nations Convention on the Law of the Sea and customary international law, the Bering Strait is considered an international strait, which means that vessels of all nations have rights to “continuous and expeditious transit of the strait.”

Fortunately, there are more pragmatic ways to mitigate the risks associated with increasing vessel traffic in the Bering Strait. Some of these measures include:

  • Improve weather forecasts and nautical charting: Weather and sea-ice forecasts in the Bering Strait are not optimal; the United States’ National Oceanic and Atmospheric Administration (NOAA) admits that weather “prediction capabilities are currently poorer in the Arctic than in other parts of the United States.” Better forecasts would help mariners identify and manage risks. In addition, the Bering Strait, along with other marine waters in the U.S. Arctic, is not charted to modern standards. NOAA’s April 2014 Arctic Action Plan describes current charting data as “inadequate or nonexistent” and recognizes that better charting “would improve maritime safety and efficiency” in the region. Nautical charts are essential tools for maritime navigation.
  • Establish vessel traffic lanes. Designating mandatory lanes for ship traffic in the Bering Strait would increase safety and reduce the chance of collisions. It would also help ensure that vessels stay well offshore, providing additional response time in the event that a ship loses propulsion or experiences some other difficulty. Additional response time may prove critical in this remote area.
  • Designate areas to be avoided. As the name implies, designation of areas to be avoided establishes regions of the ocean that are off-limits to ship traffic. In the Bering Strait, strategic designation of Areas to be Avoided would help ensure that vessels steer clear of hazards and areas that may be especially sensitive to impacts from traffic.
  • Enhance communications and reporting systems: Establishing a more robust communication and reporting protocol for the Bering Strait region would facilitate information exchange among the Coast Guard, vessels, and local communities. Some of this information exchange could be accomplished automatically, using the automatic identification systems (AIS) carried by most vessels. Two-way communication could help alert mariners to the presence of marine mammals, subsistence activities, or hazardous ice conditions in the area. Enhanced vessel monitoring could assist with the early identification of vessels in distress and encourage mariners to comply with regulatory requirements.

These are just a few possibilities. Other options are available to enhance safety, limit water and air pollution, and improve response speed and capacity in the event of an accident in the region.

While none of these options is particularly complicated, implementation of regulatory measures in the Bering Strait is made more challenging because of the region’s status as an international strait. For example, that status places limits on the ability of the United States to regulate foreign-flagged vessels transiting the strait. More comprehensive regulation can be achieved through the International Maritime Organization (IMO), but the IMO’s processes can take considerable time to unfold.

These challenges make it all the more important to get a head start on addressing the threats of increasing vessel traffic through the Bering Strait. Now is the time to set in motion the measures that will increase safety, reduce environmental risks, and enhance the capacity to respond effectively when something goes wrong.

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One of the Biggest Arctic Migrations You’ve Never Heard of http://blog.oceanconservancy.org/2014/05/12/one-of-natures-wonders-spring-migration-in-the-arctic/ http://blog.oceanconservancy.org/2014/05/12/one-of-natures-wonders-spring-migration-in-the-arctic/#comments Mon, 12 May 2014 16:29:11 +0000 Carmen Yeung http://blog.oceanconservancy.org/?p=8265

Photo Credit: NOAA National Marine Mammal Laboratory

Ocean Conservancy will be publishing a blog series exploring the wonder of the Bering Strait and highlighting threats and solutions to this region.

The Bering Strait—located between Alaska’s Seward Peninsula and Russia’s Chukotka Peninsula—is the only marine gateway connecting the Arctic Ocean and Pacific Ocean. At its narrowest point, the strait is just 55 miles wide. Big Diomede Island (Russia) and Little Diomede Island (U.S.) are located near the middle of the Bering Strait, and are separated by a strip of water less than three miles wide. Despite its cold, remote location, the Bering Strait is a key biological hotspot, a region that contains a significant number of species – some of which are found nowhere else on Earth. This strait is both a bottleneck and a pathway for marine life.

In the middle of the Bering Strait, Big Diomede Island is located to the west and Little Diomede Island is to the east.

Each spring, millions of seabirds and hundreds of thousands of marine mammals traverse the narrow strait as they migrate to the Arctic Ocean. Sea ice—frozen seawater that floats on the ocean surface—plays a major role in this seasonal migration. In the spring, migratory birds and marine mammals gather in the Bering Sea and follow the retreating ice edge north through the Bering Strait and into the Chukchi Sea and the Arctic Ocean. The ice edge is highly productive, and the sea ice itself provides important habitat for microorganisms, birds and marine mammals. The Bering and Chukchi Seas are one of the most productive ocean ecosystems in the world.

Photo Credit: NASA, May 2000

Photo Credit: NASA, August 2000

Four species of ice-dependent seals—bearded, ribbon, ringed and spotted—use the sea ice for resting and as a platform from which to feed on prey like fish, shrimp and crabs. Polar bears and Pacific walruses hunt and feed on or from the sea ice. Open areas of the ice—called leads or polynyas—attract dozens of bird species, including the short-tailed albatross, spectacled eider and Steller’s eider. These and other bird species use the Bering Strait’s rich waters for foraging and as a pathway to the summer habitat in the Arctic.

Photo Credit: NOAA Fisheries

Under the chilly spring water, nearly 10,500 bowhead whales follow leads in the sea ice as they move north through the narrow passage of the Bering. These rotund black whales use their enormous heads to break through thick sea ice. Their common name originates from their bow-shaped skulls, which are over 16.5 feet long and about 35 percent of their total adult body length. In addition to bowhead whales, beluga and gray whales travel through the Being Strait on their way north to raise their young or feed.

With huge pulses of birds and marine mammals passing through this gateway from the Pacific to the Arctic each year, spring migration in the Bering Strait is truly one of nature’s wonders. There is no question that this narrow and biologically rich stretch of water is critically important, not only to Arctic species like walruses, bowheads and spectacled eiders, but also to wider-ranging species like gray whales and migratory seabirds.

The yearly migrations of marine mammals are essential to people living in Bering Strait communities and beyond. People living in the region’s communities rely on the continued productivity of the region’s marine ecosystem to support their subsistence way of life and cultural traditions as well as to meet other economic and community needs.

Of course, fish, birds, marine mammals, and subsistence hunters do not have a monopoly on the Bering Strait. As the retreat of summer sea ice in the Arctic Ocean has accelerated, the region is attracting more attention from industry. There is growing interest in shipping, oil and gas exploration, tourism and other commercial activities that contribute to increasing levels of vessel traffic through the Bering Strait. Increased traffic in this fragile ocean space could result in more pollution, ship strikes on marine mammals, as well as chronic and catastrophic oil spills among other potential impacts to the marine environment. The Bering Strait region is particularly vulnerable because it is home to such high concentrations of wildlife. We’ll explore these issues—and potential solutions—in future blog posts.

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