Ecological Mystery Unravels, With Toxic Pesticide Use at the Center
Wednesday, May 12th, 2021(Beyond Pesticides, May 12, 2021) Earlier this year, a team of scientists solved an ecological mystery that had persisted for decades. Throughout the southeastern United States, bald eagles and other top-level avian predators were experiencing mass deaths from a disease known as vacuolar myelinopathy (VM), a neurological ailment that causes lesions in affected animal’s brains. Scientists identified the source of the exposure as a cyanobacteria growing on an invasive weed, but up until now, did not know how the bacterium caused disease. Now, scientists have determined that the chemical bromine, likely introduced by brominated herbicides in attempts to manage the invasive species, is the trigger for the production of the cyanobacteria’s neurotoxin. In the mid-1990s, over 70 bald eagles died in Arkansas’s DeGray Lake over the course of two years. The event was the largest mass mortality of eagles recorded. Scientists identified the disease as vacuolar myelinopathy, and through the course of several years were able to determine that the disease generally affected birds in the built environment, near artificial bodies of water with high levels of aquatic plant life. Waterfowl and other bird species were found to develop lesions in lakes where there was an ongoing VM outbreak. Evidence […]
