By Marc Kaufman
One of the most infamous examples of what can happen when a nonnative species is introduced into a new environment involves the brown tree snake -- a voracious, semi-venomous species that in less than 50 years all but destroyed bird life on the northern Pacific island of Guam. Introduced inadvertently from the South Pacific just after World War II, apparently on a cargo ship, the snake has killed off 10 bird species on the island and is in the process of wiping out the remaining two.
The virtual extermination of Guam's birds has been bemoaned for decades, but new research suggests that the damage to the ecology of the narrow, 30-mile-long island did not stop there.
The hundreds of thousands of snakes, researchers say, are now changing the way Guam's forest grows and will most likely cause substantial thinning and clumping of trees in the years ahead. In addition, the snakes appear to be indirectly responsible for an explosion in the spider population.
Guam, which is 3,800 miles west of Hawaii, did not have predatory snakes before the brown tree snakes arrived, and as a result the birds were not afraid of such creatures and not prepared for the onslaught. The snakes have few natural predators on the island and have at times climbed electric poles in their search for young birds, causing power outages.
"The brown tree snake has often been used as a textbook example for the negative impacts of invasive species, but after the loss of birds no one has looked at the snake's indirect effects," said Haldre Rogers, a University of Washington doctoral student in biology who presented her findings last week at the Ecological Society of America's annual meeting.
Rogers, who first went to Guam in 2002 as part of a U.S. Geological Survey "rapid response team" in a bid to keep the snakes from spreading, said she has studied tree growth on Guam and neighboring islands and has found "amazing" differences.
Without birds, which eat the seeds of certain trees and then spread them in their droppings, those trees are losing out to others that do not depend as much on bird middlemen. The seeds of the trees that relied on birds are now falling mostly near the trunks of the parent trees, where they are more likely to be spoiled by fungus and less likely to grow into healthy trees. The result, Rogers said, will either be the loss of some tree species or the clumping of those trees in isolated patches.
"It seems inevitable that the forest will change and some of the native species will lose out," she said. Birds typically make up a small part of the life of a forest, but they are important not only for spreading seeds but also for pollinating flowers and controlling some insects that feed on plants.
To test her theory, Rogers built traps of fine-mesh screen-door netting to collect falling seeds. She set 119 traps beneath and near Premna obtusifolia, or false elder, trees on Guam and on the nearby island of Saipan, which does not have the snakes. She set two traps directly beneath each tree's canopy, two about three feet away, three at 16 feet, three at 33 feet and seven at 65 feet away.
On Saipan, she found seeds in nearly every trap -- though, not surprisingly, there were more seeds closer to the trees. But on Guam, there were no seeds at all beyond the canopy of the trees. Most of the bird-dispersed seeds on Saipan also had their outer coverings removed, something that most likely occurred in the gut of a bird. Bare seeds germinate faster and result in speedier growth of new trees. None of the seeds on Guam had their coverings removed.
Rogers' team also randomly searched for seedlings of the Aglaia mariannensis (or mupunyao) tree and each seedling's most likely parent on Guam, Saipan and two other nearby islands, Tinian and Rota. All the Guam seedlings were found within 16 feet of the nearest adult tree -- most within six feet. On the other islands, the adult trees were two to three times as far from the seedlings.
Gregory Butcher, director for bird conservation at the National Audubon Society, said Rogers's research is consistent with the widely held view that birds provide "invaluable ecological services," especially in spreading plant seeds.
"We know that if birds are not present to fulfill that role, there often is nothing else that can do it," Butcher said. "The implications are severe, and that's why we consider bird conservation to be so important."
Rogers said other recent studies have shown a steady decline in bird populations, and that up to one-quarter of American species are threatened with extinction.
The population of brown tree snakes peaked on Guam in the mid-1980s, but the island remains one of the most snake-infested places on Earth -- with as many as 3,000 per square mile, some of them 10 feet long. The snakes, which are nocturnal and will eat adult birds as well as eggs, can harm young children but are not considered a danger to others. With most of the birds now gone, they live on rodents and lizards, the endangered Mariana fruit bat, and sometimes inhabitants' garbage.
Island officials continue to work to control the explosion, but Rogers said it is no longer possible to eradicate the snakes. Officials concentrate on making sure they are not on cargo ships leaving the island.
Rogers said Guam also appears now to be swarming with spiders, and her team -- which receives public, private and academic funding -- plans to survey that population as well as doing more research into the effect of birdlessness on trees. The spiders used to be controlled by the birds, she said, but now they, too, have few predators. Although a few nonnative birds have come to Guam, she said, the numbers remain small.
"Unfortunately, Guam is a laboratory of sorts for what happens when an invasive species brings major change," she said. "You can't really see it yet, but it appears that the indirect consequences for the forest can be as important as the direct consequences we saw on the bird population."
go unnoticed by the media."
"War has completely destroyed that administrative infrastructure," Coomaraswamy says, "even if they had the laws, it is impossible to implement."
(CNN) -- The young Afghan girl sits in the center of the room, weeping. Using her hand and her blue scarf to hide her face, she recounts how she was brutally raped by five gunmen.
The girl's tragic case is one of many in war-torn Afghanistan, activists say.
The 12-year-old girl's family members say they'll take their own lives unless justice is served.
"We will all commit suicide -- this is not living," cries the mother of the girl, whose gang-rape occurred in Northern Afghanistan.
The girl's adolescent voice pleads for help from Hamid Karzai, the president of Afghanistan.
The girl's elderly and immobilized father trembles and can only raise a quivering hand as he sobs. He is rendered helpless in a country where a man's dignity and honor is protecting his family.
Her little brother sits in the back, far too young to understand the situation but still traumatized by the devastated cries around him. He wipes away his tears.
The children's mother sobs. "We've been violated, we can't live our lives, we can't sit, we can't sleep at night," she says.
Video of the crushed family aired on the privately owned Ariana TV two weeks ago before it was posted on the Internet by an activist group, the Revolutionary Association of the Women of Afghanistan (RAWA).
In a country riddled with corruption, despair and lawlessness, the family has risked their lives by coming forward
They have since met with Karzai, according to an aide who said the president wept with the family and vowed to bring the perpetrators to justice. Karzai has since sacked the police chief from the city where the attack occurred, the aide said.
The family currently lives in a government-provided safe house in Kabul, Afghanistan.
"This is just an example among thousands of other cases," Shaima, a member of RAWA, tells CNN. "The restgo unnoticed by the media."
Shaima is not her real name; she uses it to protect her identity. RAWA members themselves have often been targeted for raising taboo issues in a culture in which women and children are often treated as second-class citizens.
"Women and girls, especially young girls, are the most unprotected people of Afghanistan. They are raped, kidnapped and murdered," Shaima says.
Just last week, a 3-year-old girl was kidnapped and raped by unidentified men, a government official confirms. The toddler was later released and, the official says, is recovering.
"Rapists are roaming around with impunity," Shaima says, turning her attention to a man -- said to be the son of a powerful official -- who is accused of raping 22 girls in the northern province of Sar-I-Pul.
Sayed Nurallah says his 14-year-old daughter was one of the aforementioned victims. Speaking to CNN, Nurallah says that coming forward with his daughter's story makes him a target -- which he firmly accepts. He says seeking justice for his daughter is a matter of integrity.
"She wakes up in the middle of the night screaming," Nurallah says of his daughter. "Her arms, legs, her body -- she is always tense and frightened."
Nurallah also pleads for justice. "I have one question for Mr. Karzai: If this was your little girl, what would you do?"
His firm tone changes to one of grief. He breaks into quiet sobs.
"I just want justice for my child," he says.
Shaima says justice is hard to find.
"These criminals are never brought to justice because police and government authorities are either involved or they can't handle the crimes," she explains. "With criminals and warlords in the political scene we cannot expect justice to be served."
Another factor that impedes victims from coming forward is Islamic Sharia law. In order for a rape to be validated, victims must have four male witnesses to the crime -- if not, the victims can be charged with fornication or adultery.
Statistics quantifying crimes against children are hard to come by in Afghanistan, an impoverished nation ravaged by three decades of war.
In March, the Afghan Independent Human Rights Commission (AIHRC) said deteriorating security in large parts of the country, a growing culture of criminal impunity, weak law enforcement institutions, poverty and other factors had contributed to increasing violence against women, such as rape and torture.
The AIHRC also said that Afghan girls also are often forced into marriages against their will.
Radhika Coomaraswamy, the U.N. special representative for children in armed conflict, plans to release a report in October on the state of Afghan children.
Coomaraswamy went to Afghanistan earlier this summer to establish a monitoring and reporting system on what is deemed as grave violations committed against children.
"In many cases of violence against children, there is a sense of impunity. People continue to violate children's rights without any sense of feeling that they will be held accountable," Coomaraswamy said at a news conference at the end of her trip.
She found that sexual violence against young boys is also a problem. In what is known as "bacha-bazi" -- or "child's play" -- little boys are forced to dress in female attire, dance and perform sexual acts.
"I can't think of any country in the world in which children suffer more than in Afghanistan," Coomaraswamy says. "In all our meetings with children, it takes a lot of time to make them smile. That to me shows that there is not happiness in their hearts."
She hopes that the monitoring program will deter people from taking advantage of the vulnerability of children in the combat zone. Coomaraswamy does concede that the Afghan government alone cannot do much right now.
"War has completely destroyed that administrative infrastructure," Coomaraswamy says, "even if they had the laws, it is impossible to implement."
By Misha Dzhindzhikhashvili (AP)
Israel has decided to halt all sales of military equipment to Georgia because of objections from Russia, which is locked in a feud with its smaller Caucasus neighbor, Israeli defense officials said Tuesday.
The officials said the freeze was partially intended to give Israel leverage with Moscow in its attempts to persuade Russia not to ship arms and equipment to Iran. They spoke on condition of anonymity as Israel does not officially publish details of its arms sales.
Russia has repeatedly refused to comment on reports its is selling S-300 air defense missiles to Iran.
Among items Israel has been selling to Tbilisi are pilotless drone aircraft. Russian fighters shot one down in May, according to U.N. observers.
Russia sent Israel a letter of protest after the shooting incident asking it to stop supplying military hardware to Georgia "as Russia from time to time complies with Israel's requests not to supply weapons systems" to states seen as threatening Israel, according to a report Tuesday in the Israeli daily Maariv.
The Israeli Foreign Ministry declined to comment Tuesday on the reported arms trade freeze.
Georgian Cabinet minister Temur Yakobashvili denied the report.
"There has been no decision by Israel to stop selling weapons. The gossip about that in the Israeli media is linked to the internal political process in Israel," Yakobashvili said.
Israel is one of the world's leading arms exporters but does not detail the contents or value of its trade with individual countries.
In addition to the spy drones, Israel has also been supplying Georgia with infantry weapons and electronics for artillery systems, and has helped upgrade Soviet-designed Su-25 ground attack jets assembled in Georgia, according to Koba Liklikadze, an independent military expert based in Tbilisi. Former Israeli generals also serve as advisers to the Georgian military.
Tensions between Israel and Iran are high, with Israeli officials warning of a possible military strike against what it says is a nuclear weapons program under development by Tehran. The sale by Russia of anti-aircraft weapons could help Iran fend off an attack.
Iran denies it has nuclear arms ambitions, saying its program is for peaceful purposes.
The disagreement between Russia and Georgia centers on two breakaway Georgian provinces which have close ties with Russia.
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