Even low levels of common pesticides can disturb the ability of salmon to smell, possibly reducing their chances of survival, according to research by the National Marine Fisheries Service. Salmon rely heavily on smell to help determine friends, even mates, from foes, and it may be the primary sense the fish use to navigate back to their home streams from the sea. In the past, safe pesticide levels for fish have been determined by lethality tests, but environmentalists say the new research shows that the levels must be set much lower. Two enviro groups last week said they would sue …

The Democratic Party has unveiled new TV commercials that lambaste the environmental records of George W. Bush and his running mate Dick Cheney, just in time for the Republican National Convention in Philadelphia. One ad shows an image of Texas with pollution spewing from the top of the state as if from a smokestack. The narrator notes that Bush appointed a chemical company lobbyist to enforce the state's environmental laws and that Houston is the smoggiest city in the U.S. Another ad, which criticizes votes Cheney made on a number of issues during his congressional career, points out that he …

Congress's efforts to pass the massive bills that authorize government spending are being tied up because some Republicans insist on attaching to the bills unrelated amendments called "riders," many of which aim to undermine environmental protections. Defenders of Wildlife says that Republicans have placed at least 56 anti-environmental riders on 10 appropriations bills, including measures dealing with grazing, dam removal, wetlands, drinking water standards, and global warming. One rider would delay stronger environmental regulation of hard-rock mining. Another would block an administration plan to release more water from dams on the Missouri River to improve wildlife habitat. The White House …

Tropical waters in the Northern Hemisphere have been heating up at a dramatic rate, about 1 degree Fahrenheit per decade since 1984, contributing to the unprecedented bleaching of coral reefs over the past 10 years, according to an analysis released last week by the National Oceanic and Atmospheric Administration. NOAA scientists had no explanation for the temperature increases, though global warming is a possible contributing factor. Meanwhile, global warming is certainly contributing to the shrinking of the ice cap in the Arctic. And with less ice to navigate around -- some scientists predict that by the middle of this century …

In a move that has angered the international community, Japan sent out a fleet of ships into the North Pacific on Saturday with the aim of killing three species of whales -- minke, sperm, and Bryde's. An international moratorium on commercial whaling went into effect in 1986, but Japan has continued to hunt several hundred minke whales a year under the guise of "scientific research," with the meat ending up in Japanese markets. Other countries tolerated the hunting because minkes are relatively abundant, but the U.S. and Britain are now angry because Japan this year decided to expand its "research" …

China is enduring one of the worst droughts in its history, and many experts are worrying that the nation is running out of water for its 1.3 billion people. Some 400 of China's 668 cities have declared water shortages, which means that taps may work only a few hours a day, if at all. At least 20 million Chinese citizens don't have access to any running water, and another 200 million experience serious water rationing or shortages. To make matters worse, much of the freshwater that's available is polluted. Northern China is also beset by the problem of desertification, with …

ABC News is being hit with questions about the integrity of a "20/20" report on organic foods that was aired in February and again in July of this year. The report by John Stossel claimed, among other things, that non-organic produce does not necessarily have more pesticide residue than organic produce. Stossel said this claim was backed up by research commissioned by ABC News, but the two scientists who did research for the network say they never tested produce for pesticide residue. One of the scientists did test poultry and found that samples of conventional poultry had pesticide residue while …

Virginia officials have taken the unprecedented step of declaring a 665-square-mile area of the Chesapeake Bay off-limits to fishers in order to protect the area's beleaguered population of blue crabs. Blue crabs have also been suffering in the estuary of the Altamaha River in Georgia. Long-time Georgia crabber James Holland, tired of seeing his livelihood ruined by degraded water quality, gave up catching crabs in order to concentrate on catching polluters. He formed the Altamaha Riverkeeper, an activist group that aims to clean up the waters in the state's biggest river basin. He represents a new breed of environmentalist in …

Today is Save the Koala Day in Australia, and activists hope to use the occasion to raise awareness of the animal's plight. The nation's koala population is falling by about 1,000 a year, with fewer than 100,000 in the wild, says Deborah Tabart, director of the Australian Koala Foundation. Much of the decline is due to development, which is difficult to regulate because most koala habitat is on private land. While the U.S. this year declared the koala a threatened species, even though it only exists in Australia, the Australian government still classifies it as "common." And some Australians aren't …