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More
coral bleaching events predicted
Octopus supply down, demand up
Fully biodegradable plastic now available
Ocean bottom dwellers suffer from food shortage
Gray
whales starving?
Robot fish invented
More coral bleaching events predicted
The US Department of State and the International Study for Reef Studies
predict "more frequent and severe" coral bleaching events
as a result of global warming.
As the climate continues to warm, coral reefs are exposed to an increasingly
hostile environment, said the Department of State in a statement issued
March 5.
The world suffered the most extensive and severe bleaching and mortality
in modern history in 1998, the warmest year on record. The extent of
the damage was is such that "even under the best of conditions,
many of the [affected] coral reef ecosystems will need decades to recover."
"Once the reef is reduced to rubble, fish and other marine organisms
are no longer supported," the State Department said. "Local
human populations are thus placed at risk. Over time, fisheries stocks
are greatly diminished, shoreline erosion increases and the tourist
industry is likely to suffer."
Coral bleaching occurs when corals are physiologically stressed by a
rise in sea surface temperature. It causes corals to lose symbiotic
algae, which provide them with color and nutrition. If the bleaching
episode is brief, coral reefs can survive, but if it is prolonged, the
reefs die.
The International Society for Reef Studies, an organization dedicated
to the dissemination of scientific knowledge about coral reefs, noted
that there is much scientific debate about the cause of global warming.
Nevertheless, "should seawater temperatures rise …then we
might expect the incidence and severity of coral bleaching to increase
yet further in the future with the possibility of substantial changes
to the coral reef community structure."
The Department of State said that to minimize this stress to the tropical
marine ecosystem humans need to:
"Because the issues of climate change are global
and long term in scale, governments around the world need to work together
to make available the funds that will enable these important initiatives,"
the department concluded. ENN, 05.19.99
Octopus supply down, demand up
There is a high and increasing demand for octopus from Southern Mindanao,
but supply is running short.
Exporter Susan delos Reyes said demand for octopus in the local market
is weak, but the international market is rewarding. Delos Reyes said her
company gets its supply from Zamboanga del Sur, Zamboanga del Norte, Tawi-Tawi
and even Sabah, Malaysia to meet increasing international demand. Demand
for octopus is especially high in Europe and the United States, she added.
Zamboanga is a popular source. It is one of the very rare areas in Southern
Philippines that produces more and better quality octopuses for the international
market, said Delos Reyes.
Regrettably, Delos Reyes noted, "supplies of octopus from the southern
seas have dwindled because of the massive destruction of coral reefs caused
by illegal fishing mostly using dynamite." PNA
in Philippine Daily Inquirer, 05.27.99
'Fully biodegradable' plastic now available
California-based Biocorp Inc. has developed disposable bags and cutlery
that are entirely biodegradable. Made from renewable materials, including
cottonseed and cornstarch, the products are biodegradable in a normal
composting process, yet provide the functional characteristics of conventional
plastic. They have received a seal of approval from the American Society
for Testing and Materials.
"The earlier generation of products described as biodegradable
would often fragment and break down into big pieces that would not completely
biodegrade," Allan Graf, senior executive vice president of BioCorp,said.
"Everyone realized that some standard had to be developed."
Recent ASTM Standards passed in April require that any product claiming
to be biodegradable must completely decompose into carbon dioxide or
water, the byproducts of decomposition, within a 180-day period. All
of Biocorp's products currently meet or surpass these standards.
Called reSourceBags, BioCorp's products are more expensive than conventional
bags, but offer a logical means of eliminating the traditional plastic
bag because they biodegrade in sync with yard waste. Accompanying the
bag line are reSourceWare(tm) knives, forks and spoons.
According to Biocorp, nearly 113 billion disposable cups, 39 billion
disposable eating utensils and 29 billion disposable plates are used
in the United States every year, and half these items are made of plastic.
Other groups have made headway in developing biodegradable plastic.
Researchers from the Agricultural Research Service at Beltsville, Maryland,
for example, have developed a technology for extracting fiber from feathers.
The resulting feather-fiber could be used as substitute for wood fiber
and fiberglass as well as plastics.
The extraction process was developed as a result of a government/industry
project to find a way to add value to the feathers, a by-product of
poultry production. Feather-fiber can lower costs by replacing a portion
of significantly more expensive plastic or fiberglass. They offer other
advantages, too; for example, feather fibers are more absorbent than
wood fibers. Feather fibers can lower costs by replacing a portion of
significantly more expensive plastic or fiberglass. They offer other
advantages, too; for example, feather fibers are more absorbent than
wood fibers.
Meanwhile, scientists from Adelaide, Australia have discovered that
the kind of "resistant starch" now being used to make environment-friendly
packaging can also boost health-giving bacteria in the human bowel and
may one day help save thousands of human lives. The research shows that
resistant starch promotes the growth of bifido bacteria in the gut -
the same kind of beneficial bacteria which are included in many commercial
yogurt brands.
Resistant starch is so named because it resists being digested in the
stomach and lower intestine. Instead it travels right through the digestive
tract to arrive largely intact in the large intestine (or colon), where
it has a number of significant health benefits. It is the main ingredient
of some new plant-based plastics now coming onto the market. ENN,
05.19.99
Ocean bottom dwellers suffer from food shortage
Bottom Sea dwellers in the deep eastern North Pacific are suffering
from a long-term food shortage, according to a seven-year study conducted
between 1989 and 1996. Scientists at the Scripps Institution of Oceanography
at the University of California, San Diego said a likely culprit for
the decline in food supply is a documented increase in ocean temperature
that spans the same time period. Those bottom dwelling organisms affected
by the declining food supply include a wide range of species from bacteria
and protozoa, to worms and crustaceans. The entire diet for these organisms,
which live 13,000 feet deep, ultimately comes from the ocean surface
in the form of feces, carcasses and other non-living matter.
"If the food deficit continues, it is going to change the configuration
of the deep-sea communities of organisms," said Kenneth Smith,
a research biologist in the Scripps Marine Biology Research Division
and co-author of the report in the Journal Science. "No organism
can survive long periods of time without food. There's going to have
to be some adjustments. In the long term, either the animal will have
to adapt to the shortage or a more opportunistic species will take over."
Smith and Ronald Kaufmann, a former Scripps post-doctoral researcher,
said the drop in food supply may be related to an increase in sea surface
temperatures over the same period that may have triggered a decline
in the population of zooplankton - tiny creatures that live mostly in
the surface waters of the ocean, forming a vital link near the base
of the food chain. All sorts of animals make up zooplankton, from the
larvae of large fish and invertebrates, to fully-grown worms and crustaceans.
The decline in zooplankton may in turn have led to a reduction in the
amount of food exported from surface waters to the deep ocean.
"Deep-sea communities rely on food produced in the lighted, surface
layer of the ocean in order to survive," said Kaufmann, now an
assistant professor in the Marine and Environmental Studies Program
at the University of San Diego. "A long-term reduction in surface
productivity could severely impact the amount of food delivered to the
deep ocean and profoundly impact geochemical cycling." ENN,
05.21.99
Gray whales starving?
An increase in the number of gray whale deaths could be the result of
a diminishing food supply, according to an Oregon Sea Grant researcher.
At least 65 whales are reported to have washed up on Mexico's Baja Peninsula,
where the animals migrate each winter to bear their young. And that's
not all. Additional whale corpses have been discovered along California
shores in March and April during the migration of the whales north to
their feeding grounds in the Bering Sea.
The apparent higher-than-normal mortality rate has generated widespread
speculation. Some researchers point to pollution or changes in seawater
caused by a huge salt-evaporation plant in Guerro Negro. Others suspect
that the animals were killed by cyanide in fluorescent dye used by drug
smugglers to mark the sea during airdrops of illegal narcotics.
But Oregon Sea Grant whale researcher Bruce Mate said the answer might
lie in changes to the undersea ecosystem in the whales' summer feeding
grounds off Alaska.
Mate said one possibility for the gray whale mortalities might be that
they are not getting enough to eat. The animals spend the summer months
in the Bering Sea, between Alaska and Siberia, where they fatten up
mostly on bottom-dwelling creatures called amphipods. The whales then
fast during their entire migration south without any additional snacking
until they reach Alaska again the following summer.
"So, gray whales might go without food anywhere from three to five
months," Mate said, "and those that didn't fill up the tank,
so to speak, in the Bering Sea may be returning on empty."
Researchers have noted huge changes in the Bering Sea at all levels
of the food chain, and some have theorized that those changes are part
of an even larger disruption of ocean temperature and biomass patterns.
Mate said those changes might be affecting the amount of food the gray
whales can find during the summer -- and they need a lot of food. Not
only do they need to fatten up to get through the months when they don't
eat, they also need fuel for a 12,000-mile migration from Alaska to
the Baja Peninsula -- the longest migration of any marine mammal.
Mate also noted that this year's fatalities were spread out over a long
stretch of coastline during a four-month period, indicating to him that
the deaths were not the result of a localized problem such as pollution
or drug-runners' dye. ENN,
05.20.99
Robot fish, anyone?
Japanese engineers have built a life-like, fully automatic, mechanical
fish using technology they hope will one day power ships and submersibles.
The silver-orange, 60-cm long sea bream has crowds agog as he swims
confidently around his tank wiggling his tail without any help from
his designers at Mitsubishi Heavy Industries Co. Ltd.
"The difference between this and the real fish is very small,"
said Yuuji Terada, a senior engineer at Mitsubishi. "Most people
say they are very similar."
Only the blank stare in the robot fish's eye gives him away.
Just three sea bream have been built, one of which is now on display
at a Mitsubishi museum in Yokohama, just south of Tokyo.
The fish, whose batteries allow it to swim for 30 minutes, relies on
information from sensors around the edge of the tank to determine direction.
Future versions will also be able to respond to pictures and sound.
Terada and his team have built a larger, 1.2-meter (48-inch) long machine
modelled on a coelacanth, which has more complex fin movements. They
are now working on recreating fish from the Cambrian era, 525 million
years ago.
They hope to sell their swimming robots, reportedly for tens of millions
of yen (hundreds of thousands of dollars) to museums, theme parks, and
even fish farms where anglers can practice their skills. AFP
in Sun.Star Daily, 05.24.99
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