A hunter stumbled upon a bizarre sight on a 75,000-acre ranch north of Las Vegas, N.M., on Aug. 27: the remains of more than 100 dead elk. Livestock deaths are not unusual, but so many animals dying off, and doing so in what seems to be under 24 hours, was puzzling to scientists
Officials with the New Mexico Department of Game and Fish investigated the mysterious elk deaths and ruled out several possible causes for the elk deaths, including poachers, anthrax, lightning strikes, epizootic hemorrhagic disease (an often-fatal virus known to affect deer and other ruminants), botulism, poisonous plants, malicious poisoning and even some sort of industrial or agricultural accident.
Through science and further testing of elk tissue samples and water samples, it was determined that pond scum was the culprit. Or, more specifically, a neurotoxin produced by one type of blue-green algae that can develop in warm, standing water.