Studies show water toxins poisoning birds, fish and coral
Monday, February 17, 2014, 5:16 PM -
Two separate reports -- one from the U.S. Geological Survey (USGS) and another by wildlife experts at the National Oceanic Atmospheric Administration (NOAA) -- suggest that toxins in waterways are having a devastating impact on wildlife.
POISONED BIRDS IN THE GREAT LAKES
More than 100,000 birds have been killed by eating contaminated fish in the Great Lakes since 1999, according to the USGS.
Researchers say the animals are being inflicted with avian botulism -- a disease attacks the nervous system resulting in paralysis and death by drowning.
The toxin is produced by naturally-occurring soil bacterium, which then accumulates in the fish that birds prey on.
"Botulism, we believe, is a consequence of Great Lakes ecosystems distressed by invasive species and disturbed delicate food webs," said Jonathan Sleeman, Director of the USGS National Wildlife Health Center (NWHC), in a statement. "We are working to detect botulinum toxin in the environment and determine how the toxin reaches and affects birds."
Some birds -- like the common loon and the endangered piping plover -- are more vulnerable to the disease than others.
"Outbreaks of avian botulism Type E have resulted in periodic and often severe die-offs of fish-eating birds in the Great Lakes since at least the 1960s, but have become common since 1999, particularly in Lakes Michigan and Erie," the USGS writers.
"For example, in 2012, over 4,000 botulism-afflicted birds were found dead on Lake Michigan beaches."
Scientists are working feverishly to collect data that can help predict, and hopefully stave off, the next big die-off.
"We are using data collected by beach monitors to create a statistical model, or representation, of the pulses of reported mortality in space and time," said USGS scientist Jenny Chipault.
"Repeat data from 2013 will validate and strengthen the model and ultimately help define Lake Michigan bird mortality trends."
Pollutants recovered in the sediments of Guánica Bay, Puerto Rico have demonstrated some of the "highest concentrations of PCBs, chlordane, chromium and nickel ever measured in the history of NOAA’s National Status & Trends, a nationwide contaminant monitoring program that began in 1986," according to a recent NOAA study.
"These concentrations of pollutants represent serious toxic threats to corals, fish and benthic fauna -- bottom dwelling animal life and plants," said David Whitall, Ph.D., the report’s principal investigator and NOAA ecologist, in a statement.
"We also observed lower indicators of biological health, such as how much of the coral covers the sea floor offshore from Guánica Bay when compared to an adjacent study area, La Parguera. Further research is needed to determine if this is the result of the toxins or some other cause. At this point, we cannot definitively link it to pollution."
Regardless of the cause, researchers say the study outlines the importance of contaminant monitoring.
NOAA hopes the new study will help establish baseline conditions that can be used to manage pollution in the future.