Climate: World’s biggest, oldest trees dying fast

Global trend concerns leading ecologists

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Ancient Colorado lodgepole pines have been killed by pine beetles, Bob Berwyn photo.

By Summit Voice

SUMMIT COUNTY — Colorado ‘s old lodgepoles aren’t the only forest giants that are dying. Around the world, the biggest, oldest trees that harbor and sustain countless birds and other wildlife, are meeting the same fate.

Three of the world’s leading ecologists say they’ve documented an alarming increase in the death rate of trees between 100 and 300 years old in many of the world’s forests, woodlands, savannahs, farming areas and even in cities.

“It’s a worldwide problem and appears to be happening in most types of forest,” said lead author Professor David Lindenmayer, of the ARC Centre of Excellence for Environmental Decisions and Australian National University. Continue reading

Environment: Grassroots conservation pays off in Fiji

This image from the Moderate Resolution Imaging Spectroradiometer (MODIS) on Aqua shows Fiji’s second-largest island, Vanua Levu, and the Cakaulevu Reef that shelters the island’s northern shore.

Local communities on the front line in marine protection

By Summit Voice

SUMMIT COUNTY — Local grassroots efforts to protect marine habitat are paying off in Fiji, which is making progress toward the goal of protecting at least 30 percent of Fiji’s inshore habitats.

A new study by researchers from the Global Change Institute at the University of Queensland, the ARC Centre of Excellence for Coral Reef Studies at James Cook University, and the Wildlife Conservation Society outlined some of the successes — along with some of the remaining challenges.

“The results of the study are remarkable given that locally managed marine area networks in Fiji and the Western Pacific region are generally established only to meet local objectives, most notably to improve food security,” said Dr. Morena Mills, lead author of the paper. Continue reading

Global warming: New study tries to pin down the effects of ocean acidification on shellfish

New study tries to pinpoint impacts of ocean acidification on shellfish.

Cold-water species hit hardest by increased levels of carbon dioxide

By Summit Voice

SUMMIT COUNTY — The effects of ocean acidification on shellfish are widespread around the globe and may be the most pronounced at high latitudes with low water temperatures, according to new research that examined a wide range of species from the tropics to the Arctic.

But there is some evidence that, with enough time, shellfish and other marine organisms may be able to adapt to the changes caused by global warming, according to the study published this week in the journal Global Change Biology.

“In areas of the world’s oceans where it is hardest for marine creatures to make their limestone shell or skeleton, shellfish and other animals have adapted to natural environments where seawater chemistry makes shell-building materials difficult to obtain,” said Dr .Sue-Ann Watson, formerly of the University of Southampton and British Antarctic Survey (now at James Cook University) said. “Evolution has allowed shellfish to exist in these areas and, given enough time and a slow enough rate of change, evolution may again help these animals survive in our acidifying oceans.” Continue reading

Large reef fish need table coral for shelter

A sweet lip takes shelter under a manmade structure in an Australian reef. PHOTO COURTESY JAMES KERRY.

Australian study sheds light on possible climate change impacts

By Summit Voice

SUMMIT COUNTY— New studies from Australian researchers show that big reef fish like coral trout, snappers and sweetlips have clear preferences when it comes to choosing places to hang out.

The choices big fish make on where to shelter could have a major influence on their ability to cope with climate change, according to scientists from the ARC Centre of Excellence for Coral Reef Studies at James Cook University.

In research aimed at understanding the process of fish population decline when coral reefs sustain major damage, PhD student James Kerry and Professor David Bellwood have found that big fish show a marked preference for sheltering under large, flat table corals, as opposed to branching corals or massive corals (known as bommies). Continue reading

Global warming: Is CO2 driving fish crazy?

Clownfish. PHOTO COURTESY NICK HOBGOOD, VIA THE CREATIVE COMMONS.

Researchers detect neural damage from dissolved carbon dioxide in the ocean

By Summit Voice

SUMMIT COUNTY — Rising concentrations of carbon dioxide in the ocean may cause neural damage in fish, interfering with their ability to smell and participate in synchronized schooling maneuvers that make them less vulnerable to predators.

Along with documenting the way the fish reacted to higher CO2 levels, biologists were able to show that dissolved CO2 is directly damaging the fishes’ nervous systems.

“For several years our team have been testing the performance of baby coral fishes in sea water containing higher levels of dissolved CO2 – and it is now pretty clear that they sustain significant disruption to their central nervous system, which is likely to impair their chances of survival,” said professor Philip Munday, of the ARC Centre of Excellence for Coral Reef Studies and James Cook University. Continue reading

Biodiversity: New research confirms global shark declines

A whitetip reef shark. PHOTO COURTESY NOAA.

Study: ‘Widespread, substantial, and ongoing declines in the abundance of shark populations worldwide …’

By Summit Voice

SUMMIT COUNTY — Australian researchers say they’ve developed a new way of accurately measuring shark populations, and the results show the ocean predators are in big trouble on the Great Barrier Reef and around the world.

“There is mounting evidence of widespread, substantial, and ongoing declines in the abundance of shark populations worldwide, coincident with marked rises in global shark catches in the last half-century,” said Mizue Hisano, Professor Sean Connolly and Dr. William Robbins from the ARC Centre of Excellence for Coral Reef Studies and James Cook University.

“Overfishing of sharks is now recognized as a major global conservation concern, with increasing numbers of shark species added to the International Union for the Conservation of Nature’s list of threatened species,” they wrote in the latest issue of the international science journal PLos ONE. Continue reading

Environment: Ocean acidification a ‘one-way’ experiment

Alpine Gardens underwrites Summit Voice science stories.


Clownfish in waters off East Timor. PHOTO BY NICK HOBGOOD VIA THE CREATIVE COMMONS.

Clownfish may lose hearing, become vulnerable to predators as C02 levels rise

By Summit Voice

SUMMIT COUNTY — Increasing acidification of the oceans is affecting sensory organs in fish and could make some marine species more vulnerable to predators.

Existing research shows that the CO2 in the oceans is causing some fish to lose their sense of smell. Now, a new experiment by University of Bristol scientists suggests clownfish could lose their sense of hearing as CO2 levels climb ever higher.

Since the Industrial Revolution, over half of all the CO2 produced by burning fossil fuels has been absorbed by the ocean, making pH drop faster than any time in the last 650,000 years and resulting in ocean acidification. Continue reading

Weed-eating fish seen as key to coral reef preservation

Protecting coral-grazing species like parrotfish may be critical for the survival of coral reefs. PHOTO COURTESY NOAA.

Over-harvesting of reef-grazers results in reefs being overgrown by seaweed

By Summit Voice

SUMMIT COUNTY — Spear-fishing harvests of weed-eating fish is pushing some coral reef ecosystems over the brink, according to Australian researchers. Preserving populations of species like parrotfish and surgeonfish may be vital to saving the world’s coral reefs from being engulfed by weed as human and climate impacts grow, the scientists with the ARC Centre of Excellence for Coral Reef Studies concluded.

For some years researchers have pinned their hopes on the ability of weed-eating fish to keep the weeds at bay while the corals recover following a major setback like bleaching, a dump of sediment from the land, or a violent cyclone. The weed-grazing species are key to coral reef ecosystems, but they can only keep coral reefs clear of weed up to a point. After the weeds reach a certain density, they take over entirely and the coral is lost. Continue reading

Regional cooperation needed to protect marine areas

The connection between fish larvae that are swept in from the South China Sea and the Solomon Islands to the the 'Coral Triangle' located between Indonesia, Malaysia and the Philippines is a subject great interest, as they help to demonstrate the critical interconnectedness between these ecosystems. PHOTO BY CHRISTOPHER BARTLETT.

Reefs must be linked to maintain genetic diversity

By Summit Voice

SUMMIT COUNTY — Effective preservation of marine ecosystems like coral reefs requires international cooperation at the regional level, according to recent studies in the South China Sea, the West Pacific and the Coral Triangle.

The diversity and resilience of the Coral Triangle — between Indonesia, Malaysia and the Philippines — depends vitally on coral and fish larvae swept in from the South China Sea and Solomon Islands, said researchers with the University of Miami Rosenstiel School of Marine & Atmospheric Science.

“By evaluating the directionality of larval transport over multiple generations, we could describe the signature of the extraordinary genetic diversity of the Coral Triangle. Preserving diversity is key to the health of marine systems,” said Claire Paris, Rosenstiel School assistant professor of Applied Marine Physics. “This kind of work will help us anticipate and manage changes of connectivity networks in the future.”

The authors provide evidence showing the regions’ biology is closely inter-connected, and suggesting that it is in the interests of all Asia-Pacific littoral countries to work together more closely to protect it. Continue reading

Indonesian coral reefs hit hard by global warming

La Niña spikes sea surface temps in western Pacific

NOAA tracks coral reef hotspots with a special website. Click on the image to visit the page.

Temperature-sensitive coral reefs are feeling the heat of global warming this year.

By Summit Voice

SUMMIT COUNTY — A rapid response team of marine biologists from the World Conservation Society is investigating what they say could be the most widespread incident of coral reef bleaching recorded in the past few decades.

Results of the initial May survey in May show that up to 60 percent of corals in near the northern tip of the island of Sumatra have bleached as water temperatures in the area climbed well above normal. The scientists found that 80 percent of some species have died since the initial assessment and more colonies are expected to die within the next few months.

That, in turn, will have huge impacts on the reef fishery, critical to residents of the area who depend on it for their livelihood. Continue reading

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