Thriving Oceans

It’s not rocket science!  When the vocalizations of an animal experience a world-wide decline one of the most obvious answers is a population decline…or is it?  Well, the answers definitely don’t fall within the territory of rocketry but are more suited for marine biology.  And researchers are beginning to wonder if the decline in the pitch of Blue whale songs is actually a signal of good things to come.  According to the Scripps Institute of Oceanography:

The sound level of songs blue whales sing across the vast expanses of the ocean to attract potential mates has been steadily creeping downward for the past few decades, and a scientist at Scripps Institution of Oceanography at UC San Diego and his colleagues believe the trend may be good news for the population of the endangered marine mammal.

Mark McDonald of WhaleAcoustics in Bellvue, Colo., along with John Hildebrand of Scripps Oceanography and Sarah Mesnick of NOAA Fisheries Southwest Fisheries Science Center studied blue whale song data from around the world and discovered a downward curve in the pitch, or frequency, of the songs. The decline was tracked in blue whales across the globe, from off the Southern California coast to the Indian and Southern Oceans.

“The basic style of singing is the same, the tones are there, but the animal is shifting the frequency down over time. The more recent it is, the lower the frequency the animal is singing in, and we have found that in every song we have data for,” said Hildebrand, a professor of oceanography in the Marine Physical Laboratory at Scripps.

The study’s results are published in the most recent issue of the journal Endangered Species Research.

The researchers examined a list of possible causes for the frequency drop-from climate change to a rise in human-produced ocean noise-and believe it may be explained by the increase of blue whale numbers following bans on commercial whaling activities.

While the function of blue whale songs is not known and scientists have much more to learn, they do know that all singers have been determined to be males and that the high-intensity, or loud, and low-frequency songs propagate long distances across the ocean. Blue whales are widely dispersed during the breeding season and it is likely that songs function to advertise which species is singing and the location of the singing whale.

In the heyday of commercial whaling, as blue whale numbers plummeted, it may have been advantageous for males to sing higher frequency songs, the researchers believe, in order to maximize their transmission distance and their ability to locate potential mates (females) or competitors (other males).

“It may be that when (blue whale) densities go up, it’s not so far to get to the closest female, whereas back when they were depleted it may have been that the closest female was a long way away,” said Hildebrand.

In the 1960s, when blue whale numbers were substantially reduced and recordings of the animals were first made, there may have been a tradeoff in which the male suitors chose to sing higher frequencies that were louder and heard over greater distances, Hildebrand said. In more recent years, as population sizes have increased, it may now be more advantageous for males to sing songs that are lower in frequency rather than louder.

“When they make these songs they need to use most of the air in their lungs,” said Hildebrand. “It’s like an opera singer that sees how long he can hold a note. The (male) songs are made to impress the females and/or other males, so I think that’s how the boy blue whales are impressing the girls, or are showing off to other boys: by making a loud and long song.”

The scientists say the same downward pitch phenomenon may be true in other whales such as fin and humpbacks, but the blue whale song, with a comparatively easier song to analyze, is a good springboard to study other species. Hildebrand says such knowledge about whale songs could be important in monitoring whale populations and recovery efforts.

During the study the researchers analyzed thousands of blue whale songs divided into at least 10 worldwide regions. These include the Northeast, Southwest and Northwest Pacific Ocean; the North Atlantic; the Southern Ocean near Antarctica; and the North and Southeast Indian Ocean. Blue whale songs have been recorded for the last 45 years through scientific and military applications by seafloor seismometers tracking regional earthquakes and dedicated whale acoustic recording packages.

I’ve been a bit distracted in the last couple of weeks and hence a lackluster post performance.  So time to get back to the ocean nitty gritty…

And what better way to start anew than with something to ease our appetites.  As I glance over the virtual menu I decide what the hell, “Waiter, I’ll take the tuna.”  I know I railed against overfishing, reported on the decreasing numbers of tuna, and have heard conservation organizations ask me to stay away from bluefin but no worries as the menu indicates nothing about item #13 being southern bluefin.  Oops, I guess he didn’t hear me, “WAITER, I’LL TAKE #13, THE CRITICALLY ENDANGERED TUNA…PLEASE.”

Yep, you heard it right that time.  A new study published Wednesday (Nov. 18) in PLoS has found that piece of tuna you just ordered and most likely eaten was potentially an endangered species.  And if I actually ate tuna sushi, that would be enough to make me sicker than ingesting a helping of week old sashimi leftovers.

Now that we know I’m safe from feelings of guilt and a potential bout of food poisoning, I’ll move on with the findings.  With a background in molecular biology, I love it when genetics rears its head in the world of conservation.  In this particular case, the researchers collected tuna samples from restaurants over a 7 month period in 2008 and, for the sake of brevity, used the obtained DNA to identify the species.  Here is a summary of their results:

-A piece of tuna sushi has the potential to be an endangered species, a fraud, or a health hazard. All three of these cases were uncovered in this study. Nineteen (out of 31) restaurant establishments were unable to clarify or misrepresented what species they sold.

-Twenty-two of 68 samples were sold as species that were contradicted by molecular identification, while six samples were sold as ‘‘tuna’’ or ‘‘red tuna.’’ 

-Five out of nine samples sold as a variant of ‘‘white tuna’’ were not albacore (T. alalunga), but escolar (Lepidocybium flavorunneum), a gempylid species banned for sale in Italy and Japan due to health concerns.

-Nineteen samples were northern bluefin tuna (T. thynnus) or the critically endangered southern bluefin tuna (T. maccoyii), though nine restaurants that sold these species did not state these species on their menus.

The high stakes, money making tuna market has effectively become a game of chance for the consumer. And when you can’t trust the restaurant, the menu, or the staff, perhaps it is better to err on the side of caution.  Just something to think about the next time you pick up your chop sticks.

Lowenstein, J., Amato, G., & Kolokotronis, S. (2009). The Real maccoyii: Identifying Tuna Sushi with DNA Barcodes – Contrasting Characteristic Attributes and Genetic Distances PLoS ONE, 4 (11) DOI: 10.1371/journal.pone.0007866

Press Release from Sea Turtle Restoration Project  (Nov. 5, 2009)-

Sea turtle advocates in California and family shrimp fishers from Florida filed a federal lawsuit today against the U. S. State Department for violations of the Endangered Species Act (ESA) for allowing shrimp caught in ways that are deadly to sea turtles to be sold in the United States  The lawsuit filed by the Environmental Law Clinic at Stanford Law School (Palo Alto, CA) on behalf of Turtle Island Restoration Network (Forest Knolls, CA) and the Mayport Village Association (Mayport, FL) claims that the U. S. State Department has failed to properly evaluate and prevent harm to sea turtles from overseas shrimp fleets that sell shrimp to the United States under the ESA’s Turtle-Shrimp Law (Pub. L. 101-162 § 609). It was filed in the U. S. District Court, Northern District of California. See the complaint.

“This is not only a tragedy for sea turtles, which die by the tens of thousands in shrimp nets every year, but is unfair to the U.S. fishers who obey the law and must compete in the U.S. marketplace with shrimp imports,” said Todd Steiner, biologist and executive director of Turtle Island Restoration Network a non-profit organization dedicated to the conservation of sea turtles and their habitat.

“Our Mayport shrimpers are struggling to survive, while foreign fleets get a free pass on the law and flood the market with cheap shrimp,” said Al Millar, representing Mayport Village Civic Association and its small fleet of family shrimpers based in the historic village of Mayport, FL. See www.SaveMayportVillage.net. “We work hard to fish and protect sea turtles but don’t get a break from our own government.”

The lawsuit claims that the State Department has not properly enforced requirements for foreign shrimp vessels to use nets with Turtle Excluder Devices as U. S. fishers are required to do. The lawsuit asks that the foreign shrimp certification process be given additional environmental oversight and review. Recently, shrimp imports from Costa Rica were banned due to failure to protect sea turtles after environmentalists’ complaints, but 15 other nations were certified with little, if any, scrutiny.

“There is a simple, inexpensive, and elegant solution that allows sea turtles to escape drowning in shrimp nets, called a turtle excluder device or TED” said Deborah Sivas, Stanford Law professor, and director of the Environmental Law Clinic, who filed the lawsuit.  “If the State Department can create a reasonable certification program, we can save the lives of thousands of endangered sea turtles while allowing shrimp harvesting to continue.”

Americans consume over 500,000 tons of shrimp annually, and is the top fishery import of the United States, valued at over $3.9 billion last year, according to government figures. This includes trawl-caught wild shrimp and farmed shrimp (which does not capture sea turtles but is environmentally harmful due to pollution of fish ponds and land clearing). About 90 percent of shrimp eaten in the U. S. is imported. See latest U. S. shrimp import data.

Background:
The U. S. Turtle-Shrimp Law was challenged by nations at the World Trade Organization (WTO), claiming to be a violation of the “free-trade” agreement, leading to the famous “Battle of Seattle” protests in 1999 where thousands marched peacefully to protest weak environmental protections in the global trade treaty.  The U.S. Turtle-Shrimp Law was eventually found to comply with the WTO, but poor enforcement has allowed sea turtles around the world to drown in shrimp nets and slide toward extinction. (The movie Battle of Seattle starring Woody Harrelson that dramatized the protests was released in 2008). Read more .

On May 1, 2009, the Department of State certified, pursuant to Section 609 of Public Law 101-162 (”Section 609”), that 15 nations have adopted programs to reduce the incidental capture of sea turtles in their shrimp fisheries comparable to the program in effect in the United States. Belize, Colombia, Ecuador, El Salvador, Guatemala, Guyana, Honduras, Madagascar, Mexico, Nicaragua, Nigeria, Pakistan, Panama, Suriname, and Venezuela. The Department also certified that the fishing environments in 24 other countries and one economy, Hong Kong, do not pose a threat of the incidental taking of sea turtles protected under Section 609. Read more. 

 “The United States today announced that it will seek the strongest possible management for the conservation of Atlantic bluefin tuna, a fish which is in serious trouble.

This action has two components.

First, we are sending a clear and definitive statement to the international community that the status quo is not acceptable. 

Over the past 40 years, the international body that manages bluefin tuna, the International Commission for the Conservation of Atlantic Tunas (ICCAT), has overseen a 72 percent decline in the adult population of the eastern Atlantic and Mediterranean stock of bluefin tuna and an 82 percent decline in the adult population of the western Atlantic stock. 

In recent years, the countries that fish the eastern stock, which spawns in the Mediterranean, have done so at two to three times the sustainable level, causing a significant and rapid decline in the last decade. The status of the western stock, which spawns in the Gulf of Mexico and is fished primarily off the North American coast, has recently stabilized due to the establishment of well-enforced, science-based quotas. 

A sustained lack of science-based management for the eastern Atlantic and Mediterranean stock of bluefin tuna, and concerns about slow recovery in the west, have brought us to this point. As a member in ICCAT, the United States calls for strong and definitive action at the November 2009 meeting in Brazil. This includes establishing management measures that end overfishing such as setting responsible science-based quotas, stronger enforcement of these quotas, and closures during spawning periods. 

Second, the United States strongly supports Monaco’s proposal to list Atlantic bluefin tuna under the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) to prohibit international trade of the species. The United States will consider amending or withdrawing support for the Monaco proposal if ICCAT adopts significantly strengthened management and compliance measures. 

Improving international fishery management and ending illegal, unreported and unregulated fishing are high priorities for the United States government, Congress, commercial and recreational fishermen, and conservationists.”

-Statement from Dr. Jane Lubchenco, Under Secretary of Commerce for Oceans and Atmosphere and NOAA Administrator, Announcing Support for Listing Atlantic Bluefin Tuna on International Trade Endangered Species List

As the weekend rolled to an end and the inevitable Monday workday loom overhead, I moseyed on to the bedroom and turned on the radio. Expecting to encounter a little paranormal lullaby, I was incredibly surprised to find the guest host of Coast To Coast AM, George Knapp, tackling the overfishing crisis.  In his interviews with Rupert Murray (The End of the Line) and Rick Moonen (RM Seafood), George brought this important topic of conservation concern to an international audience.  Since Coast to Coast AM is broadcast on over 500 United States affiliates alone, I was elated  to hear the notion of sustainable seafood practices being promoted to millions and perhaps recruiting some listeners to ultimately make informed and responsible meal decisions.

 And sprinkled throughout their conversations was a discussion, or warning if you will, about a vanishing act recently perpetrated by Alaskan King salmon.  Well, after a little online digging I managed to come up with an AP report (Aug. 2, 2009) on CBS News describing the failure of king salmon to return to a number of Alaskan rivers…again.

“One Alaska river after another has been closed to king fishing this summer because significant numbers of fish failed to return to spawn. The dismally weak return follows weak runs last summer and poor runs in 2007, which also resulted in emergency fishing closures.” AP

And as the salmon continue to vanish from our waters year after year, we are left speculating whether the problem is ocean currents, food availability, bycatch, aquaculture, or overfishing.  Yet over the last decade, ” the incidental number of king salmon caught has skyrocketed, reaching over 120,000 kings in 2007.” AP

Hmmm!  Perhaps a connection?  Instead of embarking on another version of the blame game and debating whether (or to what degree) the lack of salmon returns is caused by natural phenomena, such as changing ocean currents, river conditions or available prey, or human activities, we need to institute a little fisheries management tough love. 

For in the end bycatch may not be the only culprit, but as opposed to the actions of Mother Nature, it is the factor that we can definitely control.  And of the 120,000 kings killed in pollock trawl nets in 2007, an estimated 78,000 adults would have returned to the rivers of western Alaska.

AP Article: King Salmon Failing to Return to Spawn

Last Saturday my wife and I made the 2 hour journey to the Monterey Bay Aquarium, which marks our first visit in about 4 years.  As with each and every time before, I left wondering why it took me so long to get back, and most importantly how can I swing a personal 28 foot tall kelp forest aquarium…OK I admit I’m a fish lover.  But the show was not only within the confines of the plexiglass walls as the wildlife visible from the outside amphitheatre at the Great Tide Pool was amazing.

In the distance wrapped in kelp were approximately 9 sea otters. Kayaks would approach (all at a distance to prevent disturbance) and then wander away after a few minutes of enjoying the view.  Throw in a couple harbor seals, cormorants, murres, and sea lions and the bay becomes a picturesque wildlife refuge. 

Interestingly enough though, on June 30th the U.S. Geological Survey reported a 3.8% drop in sea otter numbers during the 2009 census.  A decrease of 106 individuals may not seem like a terribly large decline overall, but it keeps them below the criteria needed to remove them from the Endangered Species Act (the 3-year running averages would have to exceed 3,090 for 3 continuous years), it represents a population growth plateau for the last three years, and according to Dr. Tim Tinker of the USGS,

“This year’s census results demonstrate that sea otters continue to experience levels of mortality sufficient to limit their recovery. This highlights the need for continued efforts to understand and mitigate threats to sea otters and other species in the nearshore ecosystem.”

A more in depth examination into the cause of the declining sea otter population trend was sought out by the San Francisco Chronicle.  In a July 1st article, it was reported that deceased otters have been testing positive for bacteria, viruses, and parasites often associated with sewage, urban, and farm runoff.  Thus, are we witnessing the first signs of a pollution problem along the California coast?

And what about overfishing?  Well an inadequate amount of available favored invertebrates may be limiting nutritional intake, resulting in otters that are more susceptible to diseases and preventing the population from reaching a healthy status.

Although there are currently more questions than answers, it would not be surprising to find that the southern sea otter of California is being hindered by a combination of multiple factors.

**USGS: To reduce the influence of anomalously high or low counts during any particular year, three-year running averages of the survey results are also used to assess whether the population is growing or declining. Factors that can influence the count include viewing conditions, abundance and species composition of surface canopy kelp, observer experience, and distribution and movements of the animals.