Lisa Wilk said her husband recently visited Pastorius Reservoir, a few miles southeast of Durango, where it appeared someone had piled up about a dozen dead swallows.<\/p>\n
\u201cIt\u2019s really tragic,\u201d she said. \u201cI don\u2019t know what\u2019s going on. I know people are researching it, and making a lot of guesses.\u201d<\/p>\n
A recent report in the Las Cruces Sun-News<\/a>, which has garnered widespread attention, said that over the past few weeks an \u201cunprecedented\u201d amount of birds have been found dead from unknown causes in southern New Mexico.<\/p>\n It appears, speaking with local researchers in Durango and several residents, the mysterious deaths of numerous birds are happening here, too.<\/p>\n The first thing to note is how the birds are being found dead, said Catherine Ortega, an ornithologist and ecological consultant based in Durango. Typically, she said, birds hide under a bush or in a shrub to die.<\/p>\n \u201cIt\u2019s very strange when you get birds just dropping from the sky,\u201d she said. \u201cYou just don\u2019t see them dead out in the open. So when you do, you can tell something different is going on.\u201d<\/p>\n It\u2019s all speculation at this point, Ortega said, but she believes the birds found dead in Southwest Colorado are actually birds from the West Coast, pushed out and stressed by the unprecedented amount of wildfires.<\/p>\n \u201cMaybe they\u2019re being forced to migrate early, and they\u2019re not ready to leave,\u201d she said. \u201cAnd so if they\u2019re escaping, and their lungs have been damaged by the smoke, maybe that\u2019s what\u2019s making them drop.\u201d<\/p>\n A recent cold snap in Southwest Colorado last week brought snowfall and a dramatic dip in temperatures in the high country, which may have caused certain species to also start their migration earlier than normal.<\/p>\n Joe Szuszwalak, a spokesman for the U.S. Fish and Wildlife Service, said the cold front disrupted migration routes, causing birds to drop into areas in the southern U.S. where water and food supplies to regain energy are in short supply.<\/p>\n \u201cThis is a natural event that has been known to occur periodically,\u201d he said. \u201cWe are working with our state and federal partners, including the USGS National Wildlife Health Center, to further research this event.\u201d<\/p>\n But Arvind Panjabi with the Bird Conservancy of the Rockies said birds are hardy and can typically withstand even early season winter storms. Instead, the cold snap could have acted as a one-two punch with the wildfire smoke.<\/p>\n \u201cIt\u2019s possible they were seeking refuge and may have been weakened when the storm hit,\u201d he said. \u201cIt\u2019s really hard to say without definitively determining the cause of death for these birds.\u201d<\/p>\n It\u2019s unclear if there\u2019s any active study of the dead birds found in Southwest Colorado.<\/p>\n The Las Cruces Sun-News<\/em>, however, reported bird carcasses found in southern New Mexico were sent to the Fish and Wildlife Service\u2019s Forensics Laboratory in Oregon, though it could take weeks before results are back in.<\/p>\n \u201cIt is terribly frightening,\u201d Martha Desmond, a professor at New Mexico State University, told the Sun-News<\/em>. \u201cWe\u2019ve never see anything like this \u2026 We\u2019re losing probably hundreds of thousands, if not millions, of migratory birds.\u201d<\/p>\n An estimated 28 different wildfires have consumed more than 3.2 million acres in California this year, and 1 million acres have burned in Oregon, sending dense smoke throughout the western U.S.<\/p>\n An August 2017 study published by the Institute of Physics<\/a> highlighted just how sensitive birds\u2019 lungs are to air pollution, including wildfire smoke, which can cause respiratory distress and illness, elevated stress levels and behavior changes.<\/p>\n \u201cA fire in April of 1999 caused the death of 50 adult white ibises (Eudocimus albus) found on a cattail island,\u201d the study said. \u201cThe ibises likely became trapped due to the presence of thick smoke.\u201d<\/p>\n Panjabi said the wildfires are sending tons of pollutants into the sky at a time when birds are at peak migration.<\/p>\n \u201cThese massive fires are inescapable,\u201d he said. \u201cAnd there is ample evidence birds are very sensitive to airborne toxins. That\u2019s why they put canaries in coal mines, they die more rapidly when exposed to toxins.\u201d<\/p>\n In the western part of the U.S., birds typically follow two migration paths: the Pacific route, extending from the West Coast to about the Continental Divide, and the central route, encompassing the east side of the divide through the Midwest.<\/p>\n Southwest Colorado falls right in between the two flyways.<\/p>\n \u201cI think we\u2019re seeing (dead) birds from the Pacific flyway that have shifted to the central,\u201d Ortega said. \u201cSo we\u2019re not losing the entire country\u2019s birds \u2026 and hopefully, populations recover in a few years, but that remains to be seen.\u201d<\/p>\n When surmising about the recent die-off of birds, Ortega said she\u2019s keeping in mind the scientific principle of Occam\u2019s razor, which says when confronted with a complicated issue, usually, the answer is the most simple explanation.<\/p>\n For her, that means the culprit is wildfires, which can have a cascading effect \u2013 forcing birds into early migration, sometimes on unfamiliar routes, wiping out food sources and damaging lungs.<\/p>\n \u201cAll the fire and smoke, it\u2019s a strong candidate for the explanation,\u201d she said. \u201cBut people are scrambling to figure this out.\u201d<\/p>\n The public is encouraged to report mortality events to the USGS at https:\/\/on.doi.gov\/3kozIoS<\/a>.<\/p>\n