Sea Notes

Finding Bluefin Nurseries (and What It Means)

New confirmation today that Atlantic bluefin tunas get together on their feeding grounds but are born in nursery areas on opposite sides of the ocean. And a new chance for you to take action to protect these threatened fishes.

In an article published today in Science, researchers used the chemical composition of otoliths -- the bones in the ears of tunas -- to identify precisely where young fish spent the first year of their life. Turns out there are distinct nurseries in the Gulf of Mexico and the Eastern Mediterranean to which parent fish return to give birth.

This is further confirmation of data gathered  in more than a decade of field tagging of adult tunas by Dr. Barbara Block and other scientists at the Tuna Research and Conservation Center, a collaboration between the Monterey Bay Aquarium and Stanford University.

And it lends new urgency to calls for better management of these critical habitats -- and better protection of tunas while they're in those waters.

Action is happening on two fronts. First, the International Commission for the Conservation of Atlantic Tunas meets next month in Morocco to discuss declining tuna stocks and ways to better manage species.  To date, the commission has failed to incorporate the new scientific findings into its management practices as it presides over the collapse of bluefin tuna populations in the North Atlantic and Mediterranean. (Remember what happened to North Atlantic cod?)

Second, the National Marine Fisheries Service (NMFS) proposes that bluefin spawning grounds and juvenile bluefin feeding groups be given additional protection in the Gulf of Mexico and along the Atlantic coast. It is taking public comment on policies that would define "essential fish habitat" for bluefins and other highly migratory Atlantic species, including several kinds of sharks and other tunas.

It recommends that key waters be designated as a federal "Habitat Area of Particular Concern" (HAPC) that would "highlight the importance of the area for bluefin tuna spawning and provide added conservation benefits."

The aquarium, and other ocean conservation organizations, called three years ago for just such a designation in the Gulf of Mexico. It could happen now -- with your help. Through November 18, you can weigh in with comments on the NMFS proposal. Here's how.

Jellies: Living Room

So, if you are truly mourning the departure of our special exhibition, Jellies: Living Art, despair not!

First, don't forget, the Aquarium has a permanent collection of Jellyfish on the second floor of our Outer Bay Wing. And, what's more, now available in our bookstore (and other reputable sellers!) is a book on how to grow your own collection.

When Chad Widmer, Senior Aquarist, started working with the Aquarium's jelly collection eight years ago he wished there was one single reference source to go to. And now there is, because he wrote it! 

Says Chad, "it seemed to me that a lot of people had similar questions about jellyfish and how to keep them, but didn’t know where to look for the answers.  Information can be found in the scientific literature, but can be tricky to track down without access to a well stocked university library.  So I wrote the book from the perspective of a seasoned professional jellyfish aquarist with 8 years of experience."

The book is called "How to Keep Jellyfish in Aquariums: an Introductory Guide for Maintaining Healthy Jellies." Do let us know how you get on!

Seawater Synergy

Now here's a brilliant idea:

Pipe seawater into the Sahara Desert, use solar energy to create freshwater via evaporation, then use the water to grow greenhouse crops that will feed a hungry world. And, as a bonus, build enough solar capacity to ship surplus energy from the Sahara to Europe.

It's still a dream, but there are demonstration projects in Tenerife, Oman and the United Arab Emirates -- and a lot of buzz today about the Sahara Forest Project, Check it out.....

As if that weren't enough, the Japanese are dreaming big, too. The Times of London reports on a vision for offshore "eco-rigs" that would generate energy from the sun and waves, and use some of the energy for aquaculture farms to raise seaweed, fish and plankton.

Whale of a Report - 1

File this under Odd Science:

Our friends at the Zooillogix blog report that New England Aquarium researchers are in deep doo-doo -- whale doo-doo that is -- all in the interest of cetacean conservation.

I'll let you savor the details at Zooillogix, but for the weak of stomach, here's the CliffsNotes version.

Aquarium scientists are scooping and analyzing floating whale poop from North Atlantic right whales as a way to analyze the health of this critically endangered species.

And I thought our sea otter research team was doing well to help protect California's threatened sea otters from the perils of cat poop. In fact a visit to the sea otter exhibit at the Monterey Bay Aquarium sparked legislation to help address the threat, and finance more research into other environmental threats facing otters.

Sounds like there's an emerging and very broad field of research out there: Scatology at Sea. Any other examples I'm missing? 

Great Whites at Night

For shark lovers, National Geographic Channel is offering a cool alternative to the Discovery Channel's Shark Week. Friday night (with repeats at other times), it's airing a segment called "Sharkville" on its Wild series. The show highlights new findings that great white sharks are hunting successfully at night -- complete with infrared video footage to document the work.

There's a preview video and photos at the National Geographic Channel site, and also a video clip of the sharks at night as part of an interview with New Zealand shark researcher Ryan Johnson by Bill O'Reilly.

Most interesting is Johnson's conclusion that the sharks are able to prey on seals at night because of the light spilling onto the water from coastal development around Mossel Bay, where he did his work.

Final note: If you want to take part in white shark research projects there, the South African Marine Predator Lab occasionally offers internships.

No internships with the white shark research project at the Monterey Bay Aquarium, or with our colleagues at the Tagging of Pacific Predators. But lots of good information and images.

Two Tales of Bluefin Tuna

Following up on yesterday's post about the fishermen's strike in Japan:

Russ Parsons of the L.A. Times blogs about how strikes and high fuel costs are affecting the availability of tuna and other fresh seafood in the U.S. He also quotes Jesse Marsh of our Seafood Watch fisheries research team on the possible long-term impacts if fuel prices remain high.

Our Stanford University colleagues in Barbara Block's research lab are also blogging, this time about their success in placing electronic data tags on Pacific bluefin tuna during last week's expedition out of San Diego. They put 112 new tags on bluefin, for a total of nearly 550 tagged bluefin in the Pacific since their Tag-A-Giant program began. (Monterey Bay Aquarium partners with Stanford on the program.)

As data come back documenting the migrations of these Pacific fish, we'll begin to get a better picture about their migrations across the ocean. Similar work by the Block lab in the Atlantic has resulted in more than 1,000 tags on giant bluefin over the past decade -- and a comprehensive picture of their travels through the Western Atlantic, the  North Atlantic, Mediterranean and Caribbean.

There's data enough to support a dramatic reduction in fisheries quotas -- if the International Commission for the Conservation of Atlantic Tunas can muster the political will to impose it. Sadly, the commission seems unable to do more than preside over a collapse more dramatic than the 90 percent decline it's already suffered.

Calls for a moratorium on bluefin tuna fishing in the Atlantic were ignored last year. Since then, the European fishery was closed early and European chefs have begun to boycott bluefin tuna. ICCAT has another chance this November. We'll be watching.

Carnival of the Blue 14

It's that time again -- when the best ocean blogging from across the web comes together in the monthly Carnival of the Blue.

This month's edition is hosted by Anthony Townsend at The Blue Economy. Check it out.

Amazing migrations

It seems that every day, satellite tagging and tracking of our ocean wanderers gives us new insights into the underwater world of our ocean planet.

Scientists tracking a basking shark that visited the UK for the summer, found the female shark made a trip of close to 6,000 miles to cross the Atlantic to visit Canada. On occasion, the shark dived to depths of half a mile. Scientists doubt this trip was unique, and may have uncovered a previously unknown migration route. Prior to this, little was known about where this population of basking sharks spent the winter.

The reasons for the shark's long journey, we can only speculate - feeding, mating etc. However, there is perhaps less to ponder when we hear that a polar bear landed on the shores of Iceland recently, about 500 miles off course. Many species around the planet are responding to the pressures of our changing climate. Let's hope we heed their warning.

Learn more about the work of tagging and tracking ocean wildlife at Tagging of Pacific Pelagics website.

The State of the Seas

Not a day goes by without a headline or broadcast report about something happening to the health of the ocean. The news isn't always good, but at least more attention is focused on the largest living space on the planet. With awareness, you open the door for solutions. (In the case of the ocean, ignorance definitely isn't bliss.)

With that in mind, the bad news first:

In the Mediterranean, new research estimates that shark populations are down more than 90 percent from historic levels 200 years ago -- with all the negative impacts on overall ecosystem health that result when you all but eliminate the top predators in the system. Hammerheads, mackerel sharks and blue sharks have been wiped out as accidental bycatch, or killed as pests by fishermen who don't value their place in the ocean's living web. And, sadly, there are still few regulations in place to protect sharks in the wild.

There's also disturbing news about the presence of chemical pollutants in the deep ocean. Scientists surveying deep-water cephalopods in the northwest Atlantic Ocean have detected chemical pollutants (like tributyltin and PCBs) in the tissues of deep-sea squids. Tissue samples from deep-sea squids and octopus -- including the cockatoo squid (Galiteuthis spp.) and the vampire squid (Vampyroteuthis infernalis) -- yielded surprising concentrations of persistent organic pollutants. Chemical like tributyltin (TBT, used in anti-fouling paint on boats), polychlorinated biphenyls (PCBs), DDT and flame retardants were documented in tissue samples collected by scientists in the northwest Atlantic Ocean.

Why worry? Because these cephalopods are an important part of deep-sea food web -- including a source of food for deep-diving whales and dolphins.

On the good-news front, Southern California Edison is spending $40 million to create an artificial reef off the coast of Orange County as mitigation for damage to native kelp forests caused by discharge from its San Onofre nuclear power plant.

The 2.5-mile-long reef, mandated by the state Coastal Commission, is intended to provide footings to anchor giant kelp that will become the basis for a restored kelp forest ecosystem where wildlife can thrive.

Here in Monterey Bay, the return of sea otters from near-extirpation by fur hunters in the 18th and 19th centuries provided conditions for a similar revitalization of the kelp forests. Today, you'd never know that the bay was denuded of kelp by sea urchins, abalone and other grazers after otters were eliminated in the bay. They returned in the early 1960s, and the kelp forest followed them. Keep your eyes on San Clemente to see if the reef there has the same effect.

Finally, a celebration reported this week for "the most important microbe you've never heard of." NPR's Joe Palca took part in commemorating the discovery of a marine bacterium called Prochlorococcus. Why? Because it's super-abundant in the ocean, and is probably responsible for the oxygen in one out of every five breaths you take. Although it's one of the most abundant organisms on Earth, it was utterly unknown to science until 20 years ago.

Monday's Photo: Narwhals

They're called the unicorns of the sea. Narwhals are Arctic dwellers, related to belugas and unique because the left tooth of male narwhals grows into a twisted tusk.

Now, researchers tell us, they may become the poster child for endangered Arctic wildlife.

The March 2008 issue of the journal Ecological Applications is devoted entirely to the topic of "Arctic Marine Mammals and Climate Change." Narwhals are considered the most vulnerable to the impacts of climate change on northern ecosystems.

In an interview with the Associated Press, Stanford University biologist Terry Root (who wasn't part of the study) said the analysis published in the journal reinforces her concern that the narwhal "is going to be one of the first to go extinct" from climate change despite a relatively healthy population today.

"There could a bazillion of them, but if the habitat or the things that they need are not going to be around, they're not going to make it," Root told AP science writer Seth Borenstein.

While polar bears can adapt somewhat to the changing Arctic climate, narwhals can't, Root said.

The journal, published by the Ecological Society of America, evaluated the status of 11 Arctic marine mammals. In addition to narwhals, other species at greatest risk include polar bears, hooded seals, bowhead whales and walruses.

There's a lot we can do -- individually and as a society -- to tackle the growing volume of carbon dioxide we're putting into the atmosphere. It's the challenge of our lifetime, and well worth the effort -- for the narwhals and ourselves.