Unexplained Earth EventsCOSTA RICA - February 14 - Authorities are investigating the mysterious deaths of about 500 brown pelicans along the country's Pacific coast over five days but do not suspect bird flu was the cause. The first dead birds were spotted by a fisherman on San Lucas Island, about 10 miles from the coastal city of Punta Arenas. More turned up in the following days at nearby islands and rivers. "This is a situation that is enormously worrisome. But it is hard to know what happened, and so it is better not to speculate." Investigators were collecting tissue samples from the dead birds. Investigators do not think the deaths were caused by bird flu, which is primarily spread by migration. Brown pelicans are not migratory birds, and form stable, permanent colonies. Hospitals have been checked for possible cases of diseases like West Nile virus that could infect both birds and humans. Mosquitoes can spread that disease by biting infected birds and then biting humans. No such cases have been found so far.CALIFORNIA - HUNTINGTON BEACH – Dead and dying shorebirds are turning up around the Santa Ana River mouth, the survivors suffering from seizures and the cause unknown. Up to 50 seabirds, and possibly more, may have been affected. "We're fighting like heck to get the toxins out of them." While the symptoms the birds exhibit in some ways resemble those of domoic acid poisoning – the result of an ocean-borne toxin that can affect birds and sea mammals – there was no apparent evidence of the red tide associated with domoic acid. "We don't think it's in the food chain. It seems more like they're sharing the same area, the same water." It was unknown whether there was a threat to people swimming in the area. There were no signs of unusually high bacteria levels and no indications of chemical spills that might be affecting the water. Some high bacteria levels were seen Monday, which happens typically after storms, but those levels had dropped by Tuesday. The bird species affected included western grebes, eared grebes, ring-billed gulls, California gulls, a pelican, brants, cormorants, double-crested cormorants, a rare rhino auklet and a lesser scaup. Most of the affected birds appeared to be cormorants. An American avocet brought in Monday with seizures was among the sick birds that have survived the illness. Photo: An American avocet was having convulsions and falling backward. Cause of Marine Bird Death Still a MysteryApril 05 - Early in February and March, the beaches of Orange County saw the onset of a rash of illness and death among a variety of species of marine fowl. With many different birds found suffering within only a week's time, scientists are still looking for a cause. An estimated 25 to 30 dead cormorants were reportedly found in Newport Beach between the Santa Ana River and the city's pier. Other birds fell from the sky. Analyses were done on the blood and stomach contents of several of the birds brought into the care center that were seizing and displaying other symptoms potentially indicative of toxic algae poisoning. Algal species that produce demoic acid can bloom along the Orange County coastline, and if planktivorous fish, such as sardines and anchovy, consume the algae, they can become a demoic acid-contaminated food source for seabirds and sea lions. Only one of seven samples tested positive for demoic acid. "It's not enough to suggest that this is algal toxin-related." Lab techs were looking for evidence of fungal bacteria, and tests came back negative for organic phosphates and neoplasia. Of the birds that were brought in alive, only 10 percent recovered and were released into the wild. "As of yet, we do not know the exact cause of these deaths, but what we do know is that something acute and neurological happened to the affected birds. It's interesting that we had 14 different species that were affected the same way by the incident, and yet they all have different eating habits." With the heavy rainfall that came just before the onset of the illness in these different indigenous species to the Santa Ana River mouth, scientists are speculating that the problem may be riverborne and could have originated as far up the river as the Prado Dam. Photo: With intense care and close attention, workers at the Wetlands and Wildlife Care Center were able to save a protected American avocet.DENVER, COLORADO -The number of mysterious duck deaths is higher and more widespread than first thought and the problem is not just limited to the Metro wastewater treatment plant. Not only have dead ducks turned up at the metro Denver plant, but also along the South Platte River. Wastewater treatment plants in Thornton, South Adams County, Westminster, Northglenn, and Littleton-Englewood have also reported a higher than normal number of duck deaths. Dead ducks have also been found at the Sunfish Lake near The Breakers apartments in Denver. But at this point, nobody knows why. "No one remembers ducks dying in these kinds of numbers." The problem first showed up at the Metro wastewater treatment plant. Employees found more than 400 ducks dying from hypothermia but don't know what caused it. Plant operators have scrambled to figure out why and have come up empty. "Right now, we haven't found anything different in the water now as opposed to years past." Crews have taken the surviving ducks to rehabilitation facilities around the state. Since no one knows why the ducks are getting sick, treatment is limited. "We just give them things to help flush out what is new in their systems because wildlife are involved with a lot of environmental toxins." Scientists have ruled out avian flu and avian cholera and state health officials said the deaths may have nothing to with the treatments plants. "Histology from the birds shows no clinical signs of disease. There are no conclusive test results pointing to the cause. Additional tests are being conducted...We are focusing on what causes the ducks to lose their waterproofing as well as the cause of the malnutrition evident in many of the birds. There are many factors we need to consider in trying to investigate a die-off and we are doing all we can to methodically apply the science available to us." The state health department said one possible cause for the deaths is the abnormally cold winter.Biologists Try to Solve Duck-Die Off- State and federal biologists have ruled out several causes in the deaths of 850 ducks this winter and were still trying to figure out how they died. Avian flu, bacterial infections and exposure to heavy metals and toxins have been ruled out as culprits in the only mass duck die-off its kind nationally. "We've got more answered questions than we have answers." But the worst appears to be over, just a few dead ducks have been found in the past few days. Starting in January, several dead ducks were found at a northeast-Denver wastewater treatment plant. Others were found at other treatment plants and a lake between Boulder and Highlands Ranch. Biologists believe that most of the ducks died from hypothermia after losing their waterproofing and getting wet. One suggestion is that detergents or substances to keep water from foaming might be responsible. The cold, snowy weather likely contributed to the deaths. About 50 ducks found along the South Platte River were dry but had starved to death. Most of the ducks were Northern Shovelers, which have a large, spoon-shaped bill. The ducks have wintered in Colorado for the past several years. Some ailing ducks were nursed back to health at a sanctuary and released. About 40 ducks are still being treated.ALBERTA, CANADA - February 22 - Wildlife experts are examining another 50 ducks found dead along the Bow River on Wednesday, bringing the total number of dead birds discovered this week to 115. Test results won’t be available to confirm the cause of death until later this week, but the likely culprit is a bacteria or viral infection. It’s not likely the H5N1 strain of avian bird flu that’s been responsible for bird deaths and mass culls in other parts of the world. "There’s no reason for the public to be concerned." The rapid spread of disease isn’t uncommon among birds during the winter months when large areas of their habitat freezes, forcing them to live in closer proximity. "When we have concentrated groups of animals, it’s a breeding ground for diseases, infections (and) bacteria. This is a natural phenomenon." In previous years, large groups of birds have fallen victim to avian cholera in Calgary. MARCH -NEW ZEALAND, March 16 - Veterinarians at the University’s Wildlife Ward are investigating the cause of death of the last of a population of endangered yellow-eyed penguins hatched on Stewart Island this breeding season. Although all of the 32 chicks in the island’s Anglim coast monitoring area died, the mainland population did not appear to be affected at this stage. The last chick died of a blood parasite recently discovered on the island, but a number of diseases and environmental factors are believed to be involved in the overall mortality. Investigation is now being focused on the role of disease in Yellow-eyed penguin chicks and methods of reducing mortality. The Yellow-Eyed Penguin Trust says this year’s breeding season is the WORST SINCE MONITORING BEGAN four years ago.