2012 Jun 07. Warming nears point of no return, scientists say.
By David Perlman, SF Gate. Excerpt: The Earth is reaching a "tipping
point" in climate change that will lead to increasingly rapid and
irreversible destruction of the global environment unless its forces are
controlled by concerted international action, an international group of
scientists warns. Unchecked population growth, the disappearance of
critical plant and animal species, the over-exploitation of energy
resources, and the rapidly warming climate are all combining to bring
mounting pressure on the Earth's environmental health…scientists from
five nations, led by UC Berkeley biologist Anthony Barnosky, report
their analysis Thursday in the journal Nature….
2011 July 14. Ecosystems take hard hit from loss of top predators. By Sarah Yang and Robert Sanders, UC Berkeley News Center. Excerpt: BERKELEY — A paper reviewing the impact of the loss of large predators and herbivores high in the food chain confirms that their decline has had cascading effects in marine, terrestrial and freshwater ecosystems throughout the world. The paper, published in the July 15 issue of the journal Science by an international team of 24 researchers, presented evidence highlighting the reverberating – and often unexpected – effects the loss of “apex consumers” have had not only on immediate prey species, but also on the dynamics of fire, disease, vegetation growth, and soil and water quality...
2011 May 31. Groundwater Depletion Is Detected From Space. By Felicity Barringer, The NY Times. Excerpt:
Scientists have been using small variations in the Earth’s gravity to
identify trouble spots around the globe where people are making
unsustainable demands on groundwater, one of the planet’s main sources
of fresh water…
...Jay S. Famiglietti, director of the University of California’s
Center for Hydrologic Modeling here, said the center’s Gravity Recovery
and Climate Experiment, known as Grace, relies on the interplay of two
nine-year-old twin satellites that monitor each other while orbiting
the Earth, thereby producing some of the most precise data ever on the
planet’s gravitational variations. The results are redefining the field
of hydrology, which itself has grown more critical as climate change
and population growth draw down the world’s fresh water supplies….
…Yet even as the data signals looming shortages, policy makers have been relatively wary of embracing the findings….
2011 March 21. As Larger Animals Decline, Forests Feel Their Absence. By Sharon Levy, Environment 360 (Yale). Excerpt:
…Today native Mauritian plants, under siege from a tide of invasive
competitors and predators, hang on only in a few small conservation
management areas. Even where invasive plants are laboriously weeded out
by hand, large-fruited native tree populations are dwindling because of
a lack of fruit-eating animals to disperse the trees’ seeds….
…As part of a restoration effort on Ile aux Aigrettes, an uninhabited
islet off the Mauritius coast, the Mauritius Wildlife Federation and
the Mauritius government in 2000 introduced giant Aldabra tortoises to
test whether the tortoises could help revive native vegetation. The
tortoises are now dispersing the seeds of several native plants and are
knocking back an invasion of the exotic tree, Leuceana leucocephala, by
devouring its seedlings….
2010 September 27. Old Trees May Soon Meet Their Match. By Jim Robbins, New York Times. Excerpt:
For millenniums, the twisted, wind-scoured bristlecone pines that grow
at the roof of western North America have survived everything nature
could throw at them, from bitter cold to lightning to increased solar
Living in extreme conditions about two miles above sea level, they have become the oldest trees on the planet.
… Now, however, scientists say these ancient trees may soon meet their
match in the form of a one-two punch, from white pine blister rust, an
Asian fungus that came to the United States from Asia, via Europe, a
century ago, and the native pine bark beetle, which is in the midst of
a virulent outbreak bolstered by warming in the high-elevation West.
…The pest and the disease working together are especially deadly.
“Blister rust kills young trees rapidly,” Dr. Schoettle said. “The
mountain pine beetle only kills the larger trees, but those are the
trees that produce the seeds. So when you have a combination of blister
rust and the beetle, that severely constrains recovery of the
The long-term strategy that biologists are banking on to save the
bristlecones from dying out completely is finding the few trees that
are resistant to the fungus and growing their seeds into rust-resistant
…The bristlecones face even more fundamental changes. Warmer
temperatures are significantly altering ecosystems… Some ecologists
think that as warming continues, species that live at the top of
mountains may no longer have a niche and simply disappear, something
that has been called the “rapture hypothesis.”
…“The key to the bristlecone is that they grow in a rigorous
environment,” said Ronald Lanner, a retired forest biologist who
studied bristlecones and has written a book about them, “and that
environment is also rigorous to their pests.”
2010 May 7. Pythons in Florida Stalked by Hunters and Tourists Alike. By Damien Cave, NY Times. Excerpt:
FLORIDA CITY, Fla. — Thousands of Burmese pythons, the offspring of
former pets, have invaded the Everglades, eating birds, bunnies, even
alligators. It has gotten so bad that Congress is considering an
outright ban on buying or selling nine kinds of giant snakes.
But an odd thing has happened here in the swamp: the pythons have
become celebrities. The snakes are fast becoming an element of Florida
lore, attracting “oohs” and “ahhs” from tourists, along with groans
from biologists and even python hunters like Bob Freer.
“It’s a little frustrating and very strange,” said Mr. Freer, who
figures that his 40 captured pythons — most of which he has euthanized
— make him the state’s top private hunter. “They’re asking about
pythons that don’t even belong here, instead of alligators.”
Trouble is, the newfound fascination obscures what biologists and Mr.
Freer describe as a serious problem. In their view, python
proliferation — still significant despite a cold winter that might have
killed half the population — is simply the sexiest example of
widespread disrespect for pets and the wilderness....
2009 Fall. Hardrock Headache. By Alice Tallmadge, Forest Magazine. Excerpt:
...There’s no doubt that hardrock mining helped build the West. It
lured the curious and the inventive, the brave and the greedy, the
visionary and the hopeful across the plains and into the mountains of
the arid West. The 1872 Mining Law made land and mining cheap and laid
out a welcome mat for mining into the twenty-first century. Mining
generated communities, agriculture, railroads and commerce and built an
industry that provided a livelihood for thousands.
Now we know the earth exacts a huge price for the taking of its
minerals. Thousands of acres of public lands across the West are
affected by acid mine drainage from abandoned mines, an insidious
mining residue that can appear years after a mine has been shuttered
and can last for decades. In addition, tunnel openings, vertical shafts
and mineral-laced pools pose safety hazards for humans and wildlife.
Today, thousands of abandoned hardrock mining sites are located in the
western United States—19,000 inventoried sites on Bureau of Land
Management land and about 40,000 on national forest land. Thousands
more sites have not yet been inventoried. Because mining companies
aren’t required to post bonds for cleanup, taxpayers are footing the
bill for billions of dollars in reclamation costs that will, in some
cases, be required for decades....
* The Mine Next Door by Scott Streater
* Mining for Reform by Joshua Zaffos
* Cleanup at the Blue Ledge by Alice Tallmadge
* Reclaim and Reuse by Scott Streater
2009 August 12. NASA RELEASE: 09-185. Satellites Unlock Secret to Northern India's Vanishing Water. Excerpt:
WASHINGTON -- Using NASA satellite data, scientists have found that
groundwater levels in northern India have been declining by as much as
one foot per year over the past decade. Researchers concluded the loss
is almost entirely due to human activity.
More than 26 cubic miles of groundwater disappeared from aquifers in
areas of Haryana, Punjab, Rajasthan and the nation's capitol territory
of Delhi, between 2002 and 2008. This is enough water to fill Lake
Mead, the largest manmade reservoir in the United States, three times.
A team of hydrologists led by Matt Rodell of NASA's Goddard Space
Flight Center in Greenbelt, Md., found that northern India's
underground water supply is being pumped and consumed by human
activities, such as irrigating cropland, and is draining aquifers
faster than natural processes can replenish them....
The finding is based on data from NASA's Gravity Recovery and Climate
Experiment (GRACE), a pair of satellites that sense changes in Earth's
gravity field and associated mass distribution, including water masses
stored above or below Earth's surface. As the twin satellites orbit 300
miles above Earth's surface, their positions change relative to each
other in response to variations in the pull of gravity.
Changes in underground water masses affect gravity enough to provide a
signal that can be measured by the GRACE spacecraft. After accounting
for other mass variations, such changes in gravity are translated into
an equivalent change in water.
..."We don't know the absolute volume of water in the northern Indian
aquifers, but GRACE provides strong evidence that current rates of
water extraction are not sustainable," said Rodell. "The region has
become dependent on irrigation to maximize agricultural productivity.
If measures are not taken to ensure sustainable groundwater usage, the
consequences for the 114 million residents of the region may include a
collapse of agricultural output and severe shortages of potable
2009 August 8. Avian Silence: Without Birds to Disperse Seeds, Guam's Forest Is Changing. By Brendan Borrell, Scientific American. Excerpt: The forest on Guam is silent.
Sometime after World War II the brown tree snake arrived as a stowaway
on this U.S. Pacific island territory 6,100 kilometers west of Hawaii.
It has since extirpated 10 of the island's 12 native forest bird
species. The remaining forest birds have been relegated to small
populations on military bases, where the snakes are kept in check. In
the first study of its kind, a rugby-playing researcher named Haldre
Rogers is documenting how the forest itself is changing.
...Of the approximately 40 species of trees on Guam, about 60 to 70
percent once depended on birds to eat their fruits and disperse their
seeds. The birds may have just nicked and dropped seeds somewhere along
a flight path, or they could have swallowed the seeds, digested their
tough coats, and pooped them out with a splatter of high-nitrogen urea.
Rogers went to neighboring islands that still have birds along with
many of the same trees, collected seeds from the tree Premna
obtusifolia, and brought them back to grow in a greenhouse on Guam. She
found that seeds handled by birds are twice as likely to germinate as
seeds that simply land on the forest floor. They also germinate about
10 days more quickly, giving them a better shot at evading
seed-destroying rodents or fungi.
In another experiment, Rogers has found that seeds on Guam now always
land directly in the shade of the mother tree and always have an intact
seed coat. But seeds from neighboring islands that still have birds can
sometimes end up 10 to 20 meters away from the mother tree, where they
are more likely to find a sunny niche with fewer enemies. About 80
percent of these have had their seed coat removed, meaning they can
germinate more quickly....
..."The brown tree snake is held up as textbook example of how a
destructive invasive species can eradicate birds," she says. "This
shows that the effects of introduced predators reverberate through the
2009 August 1. An Underwater Fight Is Waged for the Health of San Francisco Bay. By Malia Wollan, The NY Times. Excerpt:
SAN FRANCISCO — Chela Zabin will not soon forget when she first
glimpsed the golden brown tentacle of the latest alien to settle in the
fertile waters of San Francisco Bay.
...The tentacle in question was that of an Asian kelp, Undaria
pinnatifida, a flavorful and healthful ingredient in miso soup and an
aggressive, costly intruder in waters from New Zealand to Monterey Bay.
The kelp, known as wakame (pronounced wa-KA-me), is on a list of “100
of the World’s Worst Invasive Alien Species,” compiled by the Invasive
Species Specialist Group. Since her discovery in May, Dr. Zabin and
colleagues have pulled up nearly 140 pounds of kelp attached to pilings
and boats in the San Francisco Marina alone.
Every year the damage wrought by aquatic invaders in the United States
and the cost of controlling them is estimated at $9 billion, according
to a 2003 study by a Cornell University professor, David Pimentel,
whose research is considered the most comprehensive. The bill for
controlling two closely-related invasive mussels — the zebra and the
quagga — in the Great Lakes alone is $30 million annually, says the
United States Federal Aquatic Nuisance Species Task Force.
Many scientists say that San Francisco Bay has more than 250 nonnative
species, like European green crab, Asian zooplankton and other
creatures and plants that outcompete native species for food, space and
2009 July 6. Some See Beetle Attacks on Western Forests as a Natural Event. By JIM ROBBINS, The NY Times. Excerpt:
MISSOULA, Mont. — When Ken Salazar — then a senator from Colorado, now
secretary of the interior — called the attack on millions of acres of
pine forests by the bark beetle the Katrina of the West, he was
expressing the common view of the explosive growth of the beetles as an
But not everybody sees it that way. Some environmentalists and
scientists support the beetles. While they acknowledge the severity of
the problems the beetles are causing, they argue that the insects,
which kill only mature trees larger than five inches in diameter, are a
natural phenomenon, like forest fires, and play a vital ecological role.
“It’s not the end of the forests, and they are not destroyed,” said
Diana L. Six, a professor of forest entomology and pathology at the
University of Montana here, who has studied the beetle for 16 years, as
she walked in a beetle-infected forest near here recently .
“Lodge pole pine evolved to go out with a stand-replacing event, such
as fire or beetles, then regenerate really quickly,” she said. “When
they hit 80 or 90 years of age all of a sudden the beetles become a
player — the trees are big enough for the beetles to attack. They reset
the clock on the stand.”
...Nothing can or should be done to halt the spread of the beetle,
experts say. After they kill the mature trees, the soil becomes more
fertile as nitrogen levels increase, sometimes tripling. The growth
rate of surviving trees increases when the infestation ends. After dead
trees fall over or burn, grass grows and provides elk habitat, and
slightly more diverse forests rise up.
...Both Dr. DeNitto and Dr. Six allow that the current outbreak is not
entirely natural. Human intervention in the form of fire suppression
and large-scale clear cuts mean that many forests are simultaneously
...The major human-caused element of the current outbreak, though, is a
warmer climate, which has opened new territory to the beetles. And this
has caused some experts to view the beetle infestations as unnaturally
2009 June 15. An Unsightly Algae Extends Its Grip to a Crucial New York Stream. By Anthony DePalma, The NY Times. Excerpt:
SHANDAKEN, N.Y. — The Esopus Creek, a legendary Catskill Mountain fly
fishing stream that is an integral part of New York City’s vast upstate
drinking water system, is one of the latest bodies of water to be
infected with Didymosphenia geminata, a fast-spreading single-cell
algae that is better known to fishermen and biologists around the world
as rock snot.
...Didymo has a natural tendency to grow upstream in fast-moving rivers
and creeks, but it can spread by clinging to fishing equipment,
especially the felt-bottom waders that fly fishermen use to keep from
slipping on river bottoms.
Didymo is considered native to parts of North America, where it was
found in higher elevations with cold, nutrient-poor waters. But in the
last 20 years, the single-celled diatom seems to have morphed into a
more aggressive invasive species, spreading from British Columbia
across the continent to New York.
Unlike other algae, which float on the surface, Didymo clings to rocks
on the bottom of rivers, streams and lakes. At times it grows furiously
in blooms that can cover a river bottom from bank to bank, smothering
the stone flies, worms and other organisms that trout and other sport
fish live on....
2009 February 16. The Unintended Consequences of Changing Nature’s Balance. By Elizabeth Svoboda, The NY Times. Excerpt:
With its craggy green cliffs and mist-laden skies, Macquarie Island —
halfway between Australia and Antarctica — looks like a nature lover’s
Mecca. But the island has recently become a sobering illustration of
what can happen when efforts to eliminate an invasive species end up
causing unforeseen collateral damage.
In 1985, Australian scientists kicked off an ambitious plan: to kill
off non-native cats that had been prowling the island’s slopes since
the early 19th century. The program began out of apparent necessity —
the cats were preying on native burrowing birds. Twenty-four years
later, a team of scientists from the Australian Antarctic Division and
the University of Tasmania reports that the cat removal unexpectedly
wreaked havoc on the island ecosystem.
With the cats gone, the island’s rabbits (also non-native) began to
breed out of control, ravaging native plants and sending ripple effects
throughout the ecosystem....
“Our findings show that it’s important for scientists to study the
whole ecosystem before doing eradication programs,” said Arko Lucieer,
a University of Tasmania remote-sensing expert... “There haven’t been a
lot of programs that take the entire system into account. You need to
go into scenario mode: ‘If we kill this animal, what other consequences
are there going to be?’ ”...
||Archive of Past Articles for Chapter 6
Excellent video (15 minutes):
Mountain Lions in Nebraska (2011)