Thursday, September 27, 2007

Adze in French Polynesia's Tuamoto came from Hawai'i

A prehistoric basalt adze found 70 years ago in the Tuamotu archipelago of French Polynesia came from volcanic rock on Kaho'olawe.

This is a huge piece of news in Hawaiian and Pacific archaeology, Polynesian culture and Pacific canoe voyaging. It is hard evidence of two-way voyaging between Hawai'i and the islands south of the equator in western Polynesia.

It may be the first hard evidence of prehistoric Hawaiian material in the South Pacific. And it confirms Polynesian oral tradition, as well as the experimental voyaging conducted by the Polynesian Voyaging Society and canoes like the Hokule'a.

Other adzes tested in the same study came from a number of different volcanic islands and further bolster the idea of a period of active long-distance voyaging by Polynesians.

The coral islands of the Tuamotu have no basalt of their own. The basalt adzes found there came from volcanic islands hundreds of miles away and from nearly every point of the compass.

Clearly, pre-European Pacific voyagers conducted regular, back and forth long-distance trade, and if not a Polynesian Grand Central Station, the Tuamoto were a key crossing point, a navigational waypoint, a trade center.

If any more nails were needed in the coffin of the concept that Polynesians were downwind “drift voyagers” incapable of windward sailing, this is it.

It's been a bad year for anyone holding the idea that Pacific voyagers weren't consummate navigators and sailors. Earlier this year, researchers found that chicken bones on the coast of Chile came from the descendants of birds brought across the Pacific by Polynesians. That was the first hard evidence of something Polynesian being found in the Americas.

Now this.

Scientists Kenneth Collerson and Marshall Weisler, of Australia's University of Queenland, published in Science (, their paper “Stone Adze Compositions and the Extent of Ancient Polynesian Voyaging and Trade.”

The 19 adzes they tested were collected by the famed Bishop Museum archaeologist Kenneth Emory from 1929 to 1934. They were found on nine coral islands, most of them low atolls—Arakita, Napuka, Takaroa, Katiu, Manihi, Ahe, Taiaroa and Nukutavake, plus the upthrust coral island Makatea.

The coral islands don't have good solid, dense-grained rock. And while a fair cutting tool can be made from things like a large clam shell, if you don't have metal, little cuts wood as nicely as hard, sharpened stone. So if you need to shape wood for canoes, for tools and for house construction, a heavy, dense, basalt adze is a nice thing.

The researchers tested the Tuamotu adzes for major elements, trace elements and isotopes, creating patterns that allowed the adze basalts to be accurately linked to their sources.

The results confirm that the Tuamotu group was a heartland of Polynesia, receiving valued hard rock from all directions—including Hawai'i.

The study found that individual adze stone came from Rapa to the south of the Tuamotu, Rurutu in the Austral Islands to the southwest, Eiao in the Marquesas to the north, the Pitcairn group to the southeast, Tahiti to the west.

And Kaho'olawe. The Kaho'olawe adze was collected on Napuka, 2,500 miles from its home lava flow.

There are several sources of stone on Kaho'olawe with the same chemical signature, and it is intriguing that one of them is very near the island's westernmost point, known as Kealaikahiki, “the way to Tahiti.

Most of the adzes, as might be expected, came from the nearest source, the Society Islands, which include Tahiti.

The Tuamotu are alternatively known as the Paumotu, the Cloud of Islands, the Dangerous Archipelago. For modern sailors, they are frightening because the islands are so low that they are frequently not visible until you can see or at night hear the surf breaking on their shores. And that's too close for comfort.

But for non-instrument navigators like the Polynesians, finding such islands was important to confirm their positions. And in the case of a long voyage from Hawai'i, if could also be a place to reprovision—since fresh food, water and other supplies would almost certainly be in low supply.

What to trade for provisions? What did the Tuamotu islanders need? Something that was easily stored in a canoe bottom and couldn't spoil. How about adze stone?

Another idea is that stones were brought as ceremonial gifts. Interestingly, modern canoe voyagers have developed independently a tradition of carrying stones from their home islands as gifts to people they visit.

“Imagine the value we place today on objects that originate from afar. They take on a special status of their own. This may be some of the value attributed to an adze brought from such a distance,” Weisler said.

The Kaho'olawe stone adze was found on the island of Napuka, in the northern part of the western Tuamotu. The adze was made of Kaho'olawe rock, but it was shaped in a Tuamotu design—suggesting that perhaps it was delivered as a raw chunk of rock, or a partly-shaped adze “blank.” And it was finished in the local style by the stoneworkers of the Tuamotus.

“The Kaho’olawe adze reaffirms that oral histories mentioning travel between Hawai’i and Tahiti are likely to have been based on real events,” Weisler said.

Furthermore, “This 4000 km journey now stands as the longest uninterrupted maritime voyage in human prehistory,” he said.

University of Hawai'i anthropologist Ben Finney, a co-founder of the Polynesian Voyaging Society, said the find appears to confirm a navigational decision made for the initial voyage of the voyaging canoe Hokule'a, for its 1976 Hawai'i-Tahiti voyage.

That decision: sail for the Tuamotu group first. It's hundreds of miles wide and hard to miss. Then, on having reconfirmed your position, sail the few hundred miles from there to Tahiti.

Did other Polynesian navigators also use the Tuamoto group, which is central in western Polynesia, as a waypoint? Or did they visit for other reasons? That's not yet known, but the visits occurred and continued to occur for an extended period of time, the paper's authors say.

“Our data show that the Tuamotu adzes originate from the Marquesas, Pitcairn, Austral and Society Islands; that is, most of the island groups surrounding the atoll archipelago ...postcolonization voyaging must have been common enough for voyaging knowledge to be passed across generations and that it continued until about 1450 CE when most voyaging ceased in East Polynesia.” they wrote. (CE, for Common Era, is the equivalent of AD, which stands of Anno Domini. 2007 CE and 2007 AD are the same year.).

This isn't the end of this adze/voyaging story. The remarkable thing about the techniques Collerson and Weisler used is that they can be applied to any basalt material, and will determine where it came from.

“Given the amount of adze material from Polynesia in museums, we believe that its quite likely that if more funding was available for our work, that we will make other very exciting and significant discoveries,” Collerson said in an email.

© 2007 Jan W. TenBruggencate

Monday, September 24, 2007

The 'Io, Hawaiian hawk, holding its own

A symbol of Hawaiian royalty and one of only two surviving native Hawaiian birds of prey, the Hawaiian hawk, 'io, is on the federal Endangered Species List, but its population appears to be at least stable and may be growing a bit.

(Photo: Michael Walther, Oahu Nature Tours)

The raptor today is only found on the Big Island, although fossil 'io have been located on several of the islands from the Big Island all the way to Kaua'i.

The animal is part of a clan of hawks called buteos, making it a cousin of the red-shouldered hawk, the red-tailed hawk and the rough-legged hawk. It has the scientific name Buteo solitarius.

The birds stand up to a foot and a half tall, and can occur in either a dark-brown or pale brown color phase. Their habitat ranges from as low as a few hundred feet to a mile and a half high. For more information see

The hawk is a powerful flyer that eats insects, rodents, small birds and will even take larger birds like pheasant. It will also take other endangered species, notably the Hawaiian crow, 'alala.

One of the issues in figuring out how much protection the birds need is getting an accurate count. It was placed on the Endangered Species List at a time when nobody knew just how many there were. Over the years, the estimates have ranged within several hundred birds on either side of 2,000.

Among the issues is that the animals are fairly broadly distributed, but not real dense.

John Klavitter, now the biologist for the U.S. Fish and Wildlife Service on Midway Atoll National Wildlife Refuge, got his master's degree in part based on a thesis that discussed counting the hawks, and developing systems for figuring out whether your count accurately represents actual numbers.

In a paper written this summer, he noted that if you use recorded playbacks of 'io calls, they show up readily. The danger here is that the playback system may make it seem that there are more of them than there really are. The paper, by Klavitter and John Marzluff, “Methods to correct for density inflation biases in Hawaiian hawk surveys using attractant calls,” was published in the June 2007 issue of the Journal of Raptor Research.

His estimate in his 2000 thesis and in a 2003 paper in the Journal of Wildlife Management suggested at at the turn of the millennium, his team figured there were nearly 1,500 of the birds. (The actual estimate was 1,457, plus or minus 176.3 birds)

Based in part on that, he recommended the birds be down listed from endangered to threatened, but not delisted altogether.

The animals appear resistant to diseases like malaria and pox that severely impact other Hawaiian birds, they seem to be long-lived, and they seem to be reproducing appropriately.

There are still issues for them. They're only present on one island, meaning random events like hurricanes, fires or other catastrophes put them at risk. Furthermore, while they seem to be benefiting from some habitat change, a complete switch from native to non-native could put them at risk, researchers said. Their main nesting tree is the native 'ohi'a.

In recent work, Klavitter and co-researchers say the populations of 'io in some native wildland areas, such as around Pu'u Wa'awa'a, are as dense as those of its cousin hawks in North America, like the red-tailed hawk.

“The reason Hawaiian hawks were so dense was likely because our study plots were dominated by mature native forest with high amounts of human-created edge habitat and extensive areas with alien grass understory. Hawaiian hawks apparently have benefited from this habitat change just as several other raptors have benefited from habitat modification elsewhere,” the authors wrote.

That's not to say 'io prefer purely non-native habitat.

They still require tall, old trees—the kind they are likely to find in native 'ohi'a forest—for nesting and other purposes. Their nests of interwoven sticks can be more than 30 feet high.

© 2007 Jan W. TenBruggencate

Saturday, September 22, 2007

Ocean acidity from CO2 could violate EPA water standards by 2050

The acidification of the oceans is proceeding so fast that
the seas could violate Environmental Protection Agency
guidelines by the middle of the century.
That's the assessment of a multinational team of scientists
writing in the Sept. 25 issue of Geophysical Research
But EPA water quality criteria are hardly the problem.
They're just paper and ink. The problem for us, said a
Hawai'i researcher who co-wrote the report, is what that
acidification could do to life around the Islands.
One key issue: the slowing growth of coral reefs that
protect many of our shorelines.
Richard E. Zeebe, an assistant professor in oceanography
with the University of Hawai'i's School of Ocean and Earth
Science and Technology, said the higher acidity could
decrease the rate of production of forms of calcium
carbonate like calcite and aragonite. (Calcium carbonate
is a base, and is eaten up by acidity.)

These compounds are the building blocks of coral reefs,
seashells and other forms of life—and they form much of
the sand on the beaches and the sea floor.

“Coral skeletons are made of aragonite, so it's likely
that calcification rates in corals will slow down with
potentially detrimental consequences for coral reef
ecosystem structure,” he wrote in an email.

How soon could there be issues?
“Given the response we see in experimental studies with
coral, it's likely that impacts are noticeable within a
few decades. Some coral studies indicate that
calcification rates could be reduced by about 50 percent
in 2050 relative to preindustrial values,” he wrote.

The paper in which Zeebe was a co-author argues that
“changes in ocean chemistry within the ranges predicted
for the next decades and centuries present significant
risks to marine biota.”

The increasing acidity is caused by the increasing amount
of carbon dioxide (CO2) in the atmosphere. One of the
other big results of this is global warming.

Before the Industrial Revolution, there were 280 parts
per million of carbon dioxide in the atmosphere. As
fossil fuels like oil and coal began forming the basis
of the world's energy supply, CO2 was a significant waste
product and ended up in the atmosphere.

Today, there's about 380 parts per million CO2 in the air.
And the researchers figure that at current rates of
fossil fuel burning, it could be 500 parts per million
by 2050 and 760 parts per million by 2100.

Lead author Ken Caldeira of the Carnegie Institution
Department of Global Ecology,

said that about a third of the CO2 formed by fossil
fuel burning ends up dissolved in the oceans. He
explains the chemistry.

“When CO2 gas dissolves in the ocean it makes carbonic
acid, which can damage coral reefs and also hurt other
calcifying organisms, such as phytoplankton and
zooplankton, some of the most critical players at the
bottom of the world's food chain.

“In sufficient concentration, the acidity can corrode
shellfish shells, disrupt coral formation and interfere
with the oxygen supply,” he wrote.

Caldeira said that for the health of the planet,
atmospheric CO2 must not be allowed to exceed 500 parts
per million.

“We need to start thinking about carbon dioxide as an
ocean pollutant. That is, when we release carbon dioxide
into the atmosphere, we are dumping industrial waste in
the ocean.”

The researchers said the solution is conservation and
quickly changing to a global energy system that produces
very little carbon dioxide.

© 2007 Jan W. TenBruggencate

Wednesday, September 19, 2007

How does sand move on or off a beach? In ripples.

Here's a question that likely never occurred to you: What role to the ripples in the sand on the sea floor play in the transport of sand?

Folks actually study that, and seriously.

(Photo: Ripples [with paw prints] just above the waterline at Virginia's Assateague Island National Seashore, Photo by Capt. Albert E. Theberge, NoAA Corps [ret.])

And in a time when most Hawai'i beaches are eroding, ripple science is a field of study that could help understand the processes at work.

Recent research on the subject, “Video-based observations of nearshore sand ripples and ripple migration,” was published in the Journal of Geophysical Research Vol. 112. The authors include J.M. Becker, Y.L. Firing, J. Aucan, R. Holman, M. Merrifield and G. Pawlak, and they conducted their study at Waimea Bay on O'ahu..

In clear, shallow water, it's easy to walk out into the sea and see the long, sinuous humps like lines of dunes on the sandy bottom. What may not be clear unless you conduct measurements, is that those sand lines are moving.

At some beaches, in smaller wave conditions, the sand ripples seem to move toward the shore, and the research team is finding that as the ripples move, so does the sand itself. In fact, “ripple migration may be an important mechanism for onshore sand transport during accretionary phases at Waimea Bay,” the scientists wrote.

Lead author Janet Becker, of the University of Hawai'i's Department of Geology and Geophysics, said ripples are dynamic. They change shape, orientation and size with different conditions.

For example, when they team worked at Waimea Bay, they found that the nearshore ocean sand ripples generally were parallel to the shore, but she said “ripples do change orientation with the direction of forcing,” by which she meant that for ripples created by waves, they change their alignment depending on the direction from which the swell was coming.

On one April morning in Waimea Bay, the team measured ripples with a wavelength of .8 meters. That means that from the peak of one ripple to the peak of another, it was about 31 inches.

Becker said that the wavelength of ripples can be associated both with the size of the grains of sand on the ocean floor, and with the wavelength of the waves passing over the bottom.

The scientists found that on that day, the ripples were moving at about a quarter wavelength in an hour toward the shore. That meant that each ripple moved about 8 inches an hour. That works out to about 16 feet per day.

The ripple itself represents sand moving from one part of the sea floor to another.

Most of the time, sand ripples are moving toward shore. But during big winter surf at Waimea, they can move away from shore.

“Large swell events cause significant beach erosion,” Becker said in an email.

Many beachgoers notice that big winter storms can suck the sand away from the shore at some beaches, while quieter summer conditions tend to replenish the beach. The researchers are trying to learn more about these patterns.

“We are looking at the time periods just following these (large swell) events to determine whether the recovery of the beach is aided in part by the shoreward migration of sand waves,” Becker wrote in the email.

The paper says that the team's work to date suggests that, in fact, it seems as if sand is being transported through the migration of the ripples—that during low waves, as ripples on the sea floor move shoreward, the sand is migrating in the same direction.

“Our preliminary results support this hypothesis, but we need to make field measurements to confirm that the migrating sand ripples really transport a significant fraction of sand,” Becker said.

“We hope to conduct an experiment on this during the winter on the north shore.”

© 2007 Jan W. TenBruggencate

Saturday, September 15, 2007

Humpbacks invade Northwestern Hawaiian Islands

The Hawaiian humpback whale, whose population seems to be on a steady growth path since whaling for the species was stopped in 1965, appears for the first time to be moving in significant numbers into the Northwestern Hawaiian Islands.

(Photo: NOAA's Ark--Animals Collection)

The whale is one of the few success stories among endangered species. As Hawaiian forest birds like the po'ouli become rare and then go extinct, as Hawaiian monk seals decline in numbers despite significant efforts on their behalf, humpbacks appear to be thriving just by virtue of the fact that we've stopped slaughtering them.

Counts in the late 1970s suggested there were only a few hundred wintering in Hawai'i. Today, numbers are in the neighborhood of 4,000, and some suggestions are that they continue to increase at about 7 percent a year..

They clearly still have problems. They are crashed into and they crash into boats, they are chopped by propellers, they are entangled in buoys lines and fishing gear. But their numbers are on the increase. An active management program under the Hawaiian Islands Humpback Whale National Marine Sanctuary helps.

Until this year, they were believed to be centered on the shallow waters around Maui County, and spreading out to the Big Island and O'ahu and Kaua'i. But scientists never saw many of them in the 1,000 miles of islands, reefs, shoals and atolls to the northwest of Kaua'i and Ni'ihau.

It was assumed anything up there was just passing through.

Now, that's clearly not the case, according to a report in the Sept. 14, 2007, online posting of the Endangered Species Journal, “Identification of humpback whale Megaptera novaeangiliae wintering habitat in the Northwestern Hawaiian Islands using spatial habitat modeling,” by Dave Johnston, Marie Chapla, Lynne Williams and David Mattila.

“This is a significant find. We've seen humpbacks expand their use of the main Hawaiian Islands but were unaware that they also used the Northwestern Hawaiian Islands as wintering habitat,” said Mattila, science coordinator of the Hawaiian Islands Humpback Whale National Marine Sanctuary.

During a March 2007 scientific cruise into the islands, now protected as the Papahānaumokuākea Marine National Monument, the researchers conducted both visual surveys by trained observers scanning the ocean from the ship, and electronic monitoring by listening underwater for whale songs.

They got numerous hits using both techniques.

“The results of our habitat analysis and survey observations document for the first time the existence of extensive wintering habitat used by humpback whales in the (Northwestern Hawaiian Islands),” the authors wrote.

They detected mothers and calves, single whales, groups of whales, and they detected whales in most of the shallow areas through three-quarters of Papahānaumokuākea, from Nihoa all the way to Lisianski.

“It was quite surprising actually. Whenever we surveyed in shallow warm areas, we found humpback whales,” Johnston said.

Whales come down from the cold feeding waters of the arctic in winter, and while in the Hawaiian Islands, they seem to prefer waters less than 600 feet deep, and more than 70 degrees Fahrenheit in temperature. There's a fair amount of that kind of habitat in the main Hawaiian Islands, but there's more to the northwest. Only at the far tip of the archipelago—around Midway and Kure Atoll-- does it appear to be too cold for their winter comfort.

The fact that the whales can use those waters is good news for the whales. Not only is there twice as much habitat for them in those islands, but they're much less likely to run into boats, or have boats run into them—largely because there aren't many boats there.

It's bad news in that there is plenty of marine debris up there, and for most of the year, no one with the capability to disentangle them. Disentanglement teams with specialized equipment are generally available to whales in the main islands.

Papahānaumokuākea is managed by the U.S. Departments of Commerce and Interior, and by the State of Hawai'i. For a copy of the research paper see For more about humpbacks, see For more information about the marine monument see or

© 2007 Jan W. TenBruggencate

Thursday, September 13, 2007

Fisheries, and the problem with sharks

Longline fisheries catch and often kill stunning numbers of sharks.

(Photo: Southwest Fisheries Science Center, NOAA)

When squid was used for bait, half the catch of the Hawai'i swordfish longline fishery was sharks. The number dropped to 32 percent after fish replaced squid as bait.

The number is less than 25 percent in Australian and Fiji longline fisheries—a smaller number but still significant.

Why is that a problem?

"Sharks and their relatives are much more vulnerable to overfishing and population collapse than bony fishes. They grow slower, mature later and have lower population increase rates. Therefore, methods to manage them may have to differ from traditional fishery management methods,” said Eric Gilman, of the World Conservation Union.

Gilman is the lead author of a new report, “Shark Depredation and Unwanted Bycatch in Pelagic Longline Fisheries: Industry Practices and Attitudes, and Shark Avoidance Strategies.”

The report was produced by the Western Pacific Regional Fishery Management Council, along with the United Nations Environmental Programme's Regional Seas Programme, Blue Ocean Institute, Consortium for Wildlife Bycatch Reduction, New England Aquarium, Project GloBAL (Global Bycatch Assessment of Long-Lived Species), and the Gordon and Betty Moore Foundation.

Researchers were from the United States, Japan, Australia, Peru, South Africa, Italy, Fiji and Chile.

The goal of the report was to learn from fishers themselves how best to reduce the unwanted catch of sharks.

A survey of captains found that you'll catch more sharks using squid for bait, using wire leaders that the sharks can't break, and fishing at certain depths preferred by sharks.

There are ways to reduce the shark catch, but they can have other impacts. For instance, if anglers use plastic leaders that sharks can cut, they will be less likely to put weights near the hooks, for fearing of losing both. That means the bait won't sink as quickly, and may be more likely to attract and hook seabirds.

There are fisheries where the sharks are an economic benefit. The boats keep the sharks and are able to sell them, and the revenue exceeds the cost of catching sharks. But in fisheries where shark take is either not valuable or not permitted by law, the costs of fishing in such a way that you catch sharks can be high.

In Hawai'i, as an example, it is illegal to simply take the shark fins and toss the rest of the shark back.

The costs of fishing in areas where sharks are caught can include damaged and lost gear, risk of crew injury in handling sharks, lost time in taking sharks off the gear, the lost opportunity to catch valuable species on hooks occupied by sharks, and so forth.

Veteran longliners are finding that they can adjust their fishing methods to increase their catch of the fish they want, and reduce their catch of sharks. More efficient fishing methods can include carefully selecting where to fish, specific times of fishing, leaving bait in the water for only limited amounts of time, fishing at specific depths and so on.

“Beyond these strategies, the state of knowledge to reduce unwanted bycatch and depredation by sharks in pelagic longline fisheries is poor,” the report said.

It proposes a number of new strategies, among them shark deterrents, which can include chemical, magnetic and electrical measures that may cause sharks to avoid fishing gear.

The study also notes, however, that there seem to be increasing markets for shark meat, meaning that sharks, instead of being troublesome bycatch, could become sought-after fish.

"Sharks are one of the world's most valuable fishery resources. They provide an important protein source, as well as a luxury item,” said Kitty Simonds, executive director of the Western Pacific Regional Fishery Management Council. The luxury item is shark fin soup.

And that increasing demand for their flesh a problem for the future of sharks, which as a group are long-lived, and which reproduce at low rates. Sharks thus are particularly vulnerable to overfishing, and will be slow to recover from it, the study says.

The world's fishery regulators thus will need to learn a lot more about the sharp-toothed predators, in order to protect them as fishing prey.

© 2007 Jan W. TenBruggencate

Wednesday, September 12, 2007

Pollutants collect on plastic marine debris

Crouch at the high-water mark on almost any Hawaiian beach and you'll find a kaleidoscope of color—not just the tans, greens and blacks of corals and volcanic stone, but also the whites, oranges, blues, reds and yellows that represent bits of plastic.

Scientists have long known that these are a mechanical problem for wildlife. That is, they fill the bellies of birds so they can't eat anything else and die.

But increasingly, it is becoming clear that they're also potentially a toxic problem—that toxic organic compounds are associated with the bits of plastic as they drift on the seas and wash up over Island reefs.

The California-based Algalita Foundation has helped conduct considerable research on drifting pollutants. University of the Pacific researchers Lorena Rios and Patrick Jones, along with Capt. Charles Moore, recently provided new insight in a paper, “Pacific organic pollutants carried by synthetic polymers in the ocean environment,” printed in the Marine Pollution Bulletin. Moore is the founder of Algalita and skipper of its research ship, Alguita.

Their research found that some plastics in the marine environment seem to absorb chemical pollutants from the environment. The research does not go so far as to show that these pollutants then get into the tissues of animals that eat the plastic—that is a study to be done later.

The problem of plastics in the ocean can't be overstated. The authors say that roughly 70 percent of marine litter is plastic. Previous studies show that plastic significantly outweighs plankton in much of the eastern Pacific.

A plastic toy, bottle or piece of fishing gear breaks in ultraviolet radiation from the sun into smaller and smaller pieces, but effectively never disappears from the environment, the authors write.

“They are not biodegradable in any practical human scale of time,” they write.

What hasn't been well studied is the relationship between these drifting and beach plastic chunks and organic pollutants. The ones studied include organo-chloride pesticides like DDT, industrial chemicals called PCBs or polychlorinated biphenyls, and polycyclic aromatic hydrocarbons (PAHs), which can be created by incomplete burning of fossil fuels, and some of which are used in chemical manufacturing.

This isn't the chemicals that are associated with plastic items when they are made, but rather chemicals that “stick” to the plastics as they move through the environment. That's a problem, because many forms of marine life, including fishes, seabirds, turtles and others, eat bits of plastic, either inadvertently as part of their regular feeding, or because they mistake bits of plastic for real food.

The researchers collected plastics, mainly polyethylene and polypropylene, from beaches in the Hawaiian archipelago, California, Mexico, from the puked-up stomach contents of seabirds, and from the surface of the North Pacific. They also collected samples from outdoor industrial sites like Mainland railyards where plastics were spilled during loading.

The plastic debris was then tested for the chemical pollutants. Not all plastic samples had detectable levels of the organic pollutants, but for instance, there was detectable DDT from Kualoa Beach on O'ahu, detectable PCBs on Kamilo Beach on the Big Island, and detectable PAH and PCB on samples from Tern Island on French Frigate Shoals in the Northwestern Hawaiian Islands.

The levels of PCBs at Tern Island was the highest found in any of the samples in the study. Tern Island has a documented PCB problem, associated with a landfill dating to the period when the island was used as a Coast Guard LORAN station.

The authors of this paper say the plastic debris seems to “absorb, accumulate and transport persistent organic pollutants.”

“These plastics are important point sources carrying (persistent organic pollutants),” the researchers write. And they're problems not only for the creature that eats the plastic, but then for the creatures that eat those creatures, and the ones that eat them.

© 2007 Jan W. TenBruggencate

Tuesday, September 11, 2007

Great white sharks: more here than we knew

Great white sharks are reported in the Hawaiian islands, though rarely.

But new research suggests they may be regular visitors that spend most of their time in deep water around the Islands so they're not noticed. And they've done so for centuries, at least.

Satellite tag data, white shark attacks and sightings all place the sharks in the Hawaiian Islands generally during the first half of the year—no earlier than December, and no later than August.

“It is likely that white sharks have been making these movements for a long time, and there are ancient records of white sharks from Hawaii in native Hawaiian artifacts and history,” wrote researcher Kevin C. Weng, of the University of Hawai'i's School of Ocean and Earth Science and Technology, in an email.

They appear to be white sharks that spend much of their team feeding on the seal and sea lions of the California coast, and which take annual forays into the mid-eastern Pacific—some to Hawai'i and most to other mid-oceanic gathering spots.

Their knowledge of the location of Hawai'i is so clear that satellite tags show that some migrations are fast and straight, from the Baja, California, coast, right to Hawai'i.

The just-published work, “Migration and habitat of white sharks (Carchardodon carcharias) in the eastern Pacific Ocean,” was printed in the journal Marine Biology. Its authors are Weng, along with Andre Boustany, Peter Pyle, Scot Anderson, Adam Brown and Barbara Block.

They report on the satellite tagging of 20 white sharks in the seal rookeries of the Baja Peninsula. Four of those sharks swam to Hawai'i during winter. Others went to other offshore aggregation sites presumably for feeding. The departures coincide with reduced seal and sea lion numbers off California.

Why Hawai'i? The authors in their paper discuss some of the local feeding choices.

“White sharks have been observed near aggregation sites for spinner dolphins on the west side of Oahu, as well as near Hawaiian monk seal colonies on Niihau, and their presence corresponds to the timing of birth for humpback whales, allowing for the possibility of feeding on placentas.

“Sharks may also forage on fishes, sharks and squids while near the islands.”

The sharks that come to Hawai'i don't appear to be of a certain class. They included both male and female, adult and subadult animals.

Why don't see see more of them? Largely because they seem to do their feeding in the deep. The satellite tags suggest that they spend only about 7 percent of their time within 16 feet of the surface.

Based on the limited samples available (4 satellite taggings) the Hawai'i sharks make their moves from the California coast at the same time most of the other white sharks do. They leave when pickings get slim in December or January. And they stay several months—a maximum recorded stay from satellite tagging data of 122 days, although there are reports of white sharks being spotted as late as August..

Anyone who does whale-watching will note that the shark season overlaps the peak of humpback whale season.

Most of the known sightings of great whites in Hawaiian waters have been during the early part of the year, although individuals have reported seeing what they believed were white sharks as late as July and August.

Clearly, the animals have been traveling to Hawai'i for hundreds of years. Some early Hawaiian tools have used the teeth of white sharks for cutting edges.

Two known shark attacks on humans occurred in May 1926, when the remains of William Goins were found inside a 12.5-foot white caught off Kahuku. In March 1969, a white shark bit surfer Licius Lee off Makaha. The animal was identified by its characteristic tooth marks in his surfboard. The area is known for nearby spinner dolphin populations, and there was a dead whale on the beach at about that time.

Hawai'i residents have reported great whites during summer in recent years off Makua, Keawa'ula and Ma'ili. Witnesses said they believe a shark that bit a woman off Ka'anapali in 1999 was a white. And the species has been seen in the waters off northern Ni'ihau repeatedly during the 1990s.

The satellite tagging results confirm the presence of the animals in those regions.

Weng said that there are still several mysteries about the behavior of white sharks, including a suggestion that some females may only return to the California coast every other year.

Does that mean that in places like Hawai'i there might be a year-round great white shark presence? Weng said he can't say, and researchers may have to wait for technology to catch up with the research needs.

Currently available satellite tags don't seem to last more than about 9 months, he said. What's needed is a way to electronically track the sharks for a period of years.

As in much of science, it's a field that demands more research.

© 2007 Jan W. TenBruggencate

Friday, September 7, 2007

Protecting marine life: more than just a ban on harvesting

If you're going to run cattle, you need to not only manage the cows, but also the pasture.

It's a message that seems self-evident, but may be missed by some of those who would manage marine life by banning harvesting alone.

With reef fish, for example, if you seek to protect them, you need to also protect the reef itself. That's the conclusion of Edward DeMartini, of NOAA's Pacific Islands Fisheries Science Center in Honolulu, and Todd Anderson, of San Diego State University. Their study on the subject was published in the Bulletin of Marine Science (2007, Bulletin of Marine Science 81:139-152).

The two studied the behavior of baby fish, including yellow tang, kole and others, at three Big Island locations, one of them a protected site, one open to wind and waves, and one semi-protected.

They found that when possible, they often clustered within the branches of finger corals. The corals provide them two key things: food and protection.

“The Hawaiian-endemic finger coral Porites compressa provides essential habitat for juvenile yellow tang, kole, and numerous other reef fishes,” DeMartini wrote in an email.

“Finger coral provides an essential habitat for many species of herbivorous (algae-eating) fishes because its dead basal surfaces (surfaces on which turf algae proliferate) also provide shelter from predation by fish-eating fishes,” he wrote.

It's clearly not simply that they happen to occur here, but such sites form preferred shelter for these small fish. And that means the little fishes are more likely to survive to become big fishes.

There's more science to be done on the issue, but the scientists said that clearly the complex structure of a healthy reef is an important part of protecting the fish life on it. It suggests, for example, that it's not enough to simply tell people they can't kill a species. You also have to prevent folks from smashing the bottom with boat anchors, from breaking up corals as they walk on the reef, and from letting muddy water smother the nearshore ocean floor.

“Corals habitat also must be protected from destructive human influences such as anchor damage and the sedimentation that results from unregulated coastal development, in order to preserve the juvenile habitat that is necessary for population replenishment,” DeMartini wrote.

© 2007 Jan W. TenBruggencate

Thursday, September 6, 2007

When volcanoes collide: Kilauea and Mauna Loa briefly (!) linked underground

Do Mauna Loa and Kilauea draw molten rock from the same source?

Geologists agree that in a larger sense they do—both gain their magma from what's called the Hawaiian plume, a place where molten rock from the earth's core punches up through the mantle of the earth to create volcanoes.

(Image at upper right, from Hawaiian Volcano Observatory, shows current eruption of Kilauea, below Pu'u 'O'o on the East Rift Zone.)

But volcano scientists have long known that chemically, the rocks erupted by Mauna Loa are different from those coming out of Kilauea. That suggests, they say, that while they may both draw from the plume, they probably draw from different places in the plume.

But a new paper says that for a brief moment in geologic time, from about 250 AD to 1400 AD, the two volcanoes were spewing largely the same stuff.

University of Hawai'i geologist Michael Garcia said that the best guess is that during that period, there was a single source that fed both volcanoes, but that both before and after that, lava produced in eruptions of the volcanoes came from different places..

“The notion is that a blob of material was under both volcanoes for a short time in the recent past,” Garcia said in an email.

“Otherwise, the sources of the two closely spaced volcanoes are distinct for many hundreds of thousands of years,” he wrote.

The July 15 issue of the journal “Earth and Planetary Science Letters” contains the paper by Jared Marske, Aaron Pietruszka, Dominique Weis and Michael Rhodes and Garcia. It is entitled, “Rapid passage of a small-scale mantle heterogeneity through the melting regions of Kilauea and Mauna Loa Volcanoes.”

Scientists use all kinds of techniques to try to envision what's under the volcanoes, and the chemistry of rocks is among them. The best assessment is that during this period, during the period Hawaiians were populating the Hawaiian archipelago, coming up from deep in the earth, “there was a filament that was large enough to be tapped by both volcanoes,” Garcia said.

The scientists studied the ratios of isotopes of three elements—lead, strontium and neodymium—in lavas of both volcanoes. Normally, the two volcanoes have distinctly different lava composition, but during the period in question, the compositions seemed to blend into each other.

“The Kilauea lavas span the (lead) isotopic divide that was previously thought to exist between these two volcanoes,” the authors write.

The lavas “moved towards an intermediate composition, and subsequently returned to typical values.”

© 2007 Jan W. TenBruggencate

Monday, September 3, 2007

Superferry: What the Hawai'i Supreme Court really said

Almost everybody has missed key points in the Hawai'i Supreme Court's Superferry ruling.

Not surprising, perhaps. The ruling is 104 pages long. A small book. Who had time to read it on deadline?

Off deadline, we spent some time with it.

The Superferry is a business that proposes to run high-speed passenger-and-cargo vessels between Hawai'i ports.

The Hawai'i Supreme Court shocked the business, environmental and government communities by ruling on an appeal that the state Department of Transportation (DOT) needs to conduct environmental assessment (EA) for its harbor improvements that benefit the Hawai's Superferry, as well as on some of the direct impacts of the Superferry operation itself.

Before a lower court could issue rulings giving force to the Supreme Court decision, the ferry folks decided to start operating.

Kaua'i residents shocked Superferry passengers, the Coast Guard, the state and to some degree the nation when dozens of them leaped into the ocean to form a human blockade preventing its access to Nawiliwili, the primary harbor on Kaua'i.

It made national news.

Many of the protestors argued with the Coast Guard personnel trying to haul them aboard or shove them out of the way. They weren't the lawbreakers, they said, the ferry was.

The Hawai'i Supreme Court ruling is complicated, but it seems clear that the ferry wasn't actually the lawbreaker.

The lawbreaker was the state Department of Transportation, which owns the harbor in which the protesters were swimming.

But it's also clear that the ferry was pretty audacious in deciding to begin running passengers into the seriously murky legal waters created by the court.

Here are some of the results of a reading of the court ruling, which at this writing (Aug. 3, 2007) is being considered by the 2nd Circuit Court on Maui.

A warning: This is going to get a little technical, but not nearly as technical as the actual ruling, which is available on the web from the August 2007 files at:

*** One of the first issues is one that will benefit citizen pro-environment movements for years to come. (We'll get to the Superferry stuff, but this piece of the case may be more important, ultimately, than that.)

The Maui Circuit Court had ruled that the Maui Sierra Club, Maui Tomorrow and the Kahului Harbor Coalition lacked standing—meaning they couldn't claim relief because they weren't sufficiently affected by the DOT's failure to do an EA.

The environmental groups claimed four injuries: threats by the Superferry to endangered marine species; the threat of introducing alien species to the island; limitations due to the Superferry's operation to recreational uses in harbors; and traffic problems. In short, whales, coqui frogs and miconia, canoes and surfers, and finally, traffic jams.

The Supreme Court ruled that they did have a right to sue, that a band of citizens has an interest in whether the state is doing right by the environment—a right sufficient to go take to court.

“If these Appellants do not have standing to bring this claim, it is hard to imagine who, if anyone, would,” the court said.

The Supreme Court said that the right to sue in environmental cases is derived in part directly from the state Constitution, and that legal standing must be more readily granted in environmental cases than in others.

**** The Maui court ruled that even if the environmental groups had standing to sue, the DOT did the right and legal thing in exempting itself from doing an EA.

The DOT asked the state Office of Environmental Quality Contol whether the Superferry harbor improvements fell into a couple of categories for which exemptions from an EA are permitted.

But the Supreme Court said it's not enough for DOT to simply conclude that a project fits into an exemption category--it actually has to make a review and correctly conclude there will be no significant environmental impact.

“...blind deference to agency exemption determinations is not appropriate,” the court wrote.

**** The Supreme Court said that the crucial issue in the case is whether the DOT was right in considering only the specific harbor improvements in deciding not to do an EA. Because, the court said, if it considered the larger issue of the Superferry's overall impact, there would be no question.

“If DOT was required to consider the Superferry project itself, as opposed to the harbor improvements alone, in making this exemption determination, it is clear that the exemption would not apply,” the court said.

That's clear, the court said, in part because of the Superferry's own actions. When the ferry company announced it had developed internal policies to minimize its environmental impact, even though not admitting there would be significant impacts, the comments “make it clear that the Superferry project itself—were its environmental effects considered—does not meet the standard of an exempt action.”

The court said that the DOT clearly failed to consider “whether its facilitation of the Hawaii Superferry Project will probably have minimal or no significant impacts, both primary and secondary, on the environment.”

And in failing to consider that, it was wrong, the court said.

The court ruled DOT's exemption from the EIS process invalid.

“The exemption being invalid, the EA applicable,” the court said.

The Supreme Court went on to note that while Hawai'i Superferry's voluntary decision to develop its own environmental policies is a good thing, it's not he same as a public process, which by definition allows public participation.

“The public was prevented from participating in an environmental review process for the Superferry project by DOT's grant of an exemption,” the court said.

**** What's still left unsaid is how broad an environmental review is needed. Clearly, the Supreme Court decision requires that an EA be performed, and must consider both the harbor improvements and “the secondary impacts on the environment that may result from the use of the Hawaii Superferry in conjunction with the harbor improvements.”

Does that mean the Maui court can simply limit the EA to direct impacts of the Superferry on Maui harbor users and Maui island drivers, farmers and so on? Presumably it could, but it's also clear that such a ruling could take it right back on appeal before a Hawai'i Supreme Court that has already expressed serious concern with the legality of such limits.

The court does not specifically say that the DOT needs to do an environmental review that considers the Superferry's statewide impact, but that seems to be the essence of its message. And indeed, in meetings with stakeholders Monday, Sept. 3, the DOT said its EA would in fact include all the island harbors to be used by the Superferry.

*** Some folks have argued that citizens stepped up to the plate too late on the Superferry issue. But most of the same arguments we hear today were being made three years ago when the ferry was before the state Public Utilities Commission for a permit. And the PUC, far from deciding an EA or environmental impact statement (EIS) wasn't necessary, said there were in fact “important issues that should be addressed.”

The PUC failed to require a study, the Supreme Court ruling says in a footnote, because 1) the PUC expected the DOT to consider the issues and 2) the Hawai'i Legislature “has determined that this application should be processed expeditiously.”

© 2007 Jan W. TenBruggencate

Saturday, September 1, 2007

Ocean acidity--the next big climate thing

The next big thing in the
climate change debate is
the changing acidity of
the oceans.
Researchers in Hawai'i are
among scientists worldwide
who are tracking the slow
but apparently quite real
movement of the oceans from being slightly basic toward
being acidic.
The argument is that this is a direct result of the
increasing amounts of carbon dioxide in the atmosphere.
(This is going to get a little technical, but
essentially, carbon dioxide, which comes in part
from the burning of oil and coal, is a greenhouse gas.
It's a major cause of global warming. And while there
are still some folks out there debating whether 1. there
is global warming, or 2. whether that's a bad thing--there
is no real debate that 3. the percentage of carbon
dioxide in the atmosphere has increased dramatically
in the past century, and continues to rise.)
(When you mix carbon dioxide with water, you get a mild
acid. More carbon dioxide, a higher concentration of
acid. So at its simplest, that's what's going on with
the oceans—more carbon dioxide in the air, and the
oceans become more acid.)
The Center for Biological Diversity
( has recently asked seven
coastal states, including Hawai'i, to act on this.
That's because these are the states most likely to
suffer from changing ocean acidity.
The organization has asked Alaska, Florida, Hawai'i,
Oregon, New Jersey, New York and Washington to declare
their coastal waters impaired under the Clean Water Act.
California was asked to do so earlier.
“Ocean acidification is quietly, lethally altering the
fundamental chemistry of the world's oceans. We must
act now to prevent global warming's evil twin, ocean
acidification, from destroying our ocean ecosystems,”
wrote Miyoko Sakashita, an attorney and head of the
center's oceans program.
Alkalinity or acidity is measured on a pH scale from
1 to 14, in which 1 is very acid and 14 is very
alkaline. Neutral is 7.

Lemon juice is quite acid, with a pH of 2.4, while
hand soap, which is alkaline, is about 9 or a little

The oceans are slightly alkaline, at about 8. But with
the increasing carbon dioxide in the atmosphere,
oceanic pH has decreased by a little more than a tenth
of a point. It's not a lot, but nobody knows yet (lot
of research is getting started) at what point the
change begins causing reefs to decompose and sea
creatures' shells to stop forming.

Sakashita says the carbon dioxide is increasing so
rapidly that the oceans will change their pH faster
than species can evolve and adapt.
The Center for Biological Diversity hopes that the
Clean Water Act might be used as a lever to force
changes in the society's production of carbon dioxide.

“If ocean waters are listed (as impaired), the law would
require states to limit carbon dioxide pollution entering
the ocean waters under their jurisdiction,” Sakashita
said in a press release.

© 2007 Jan W. TenBruggencate