Research team documents severe ill-effects in Barataria Bay
By Summit Voice
SUMMIT COUNTY — Many dolphins in Louisiana’s Barataria Bay — one of the areas hit hardest by the 2010 Deepwater Horizon oil catastrophe — are underweight and anemic, have low blood sugar and suffers symptoms of liver and lung disease, NOAA researchers said this week.
Nearly half of the 32 dolphins studied also have abnormally low levels of hormones that help with stress response, metabolism and immune function, biologists said, releasing preliminary results of a natural resource damage assessment to help responders deal with a steady stream of dolphin strandings along the tainted coastline. A NOAA dolphin FAQ is online here.
Barataria Bay, located in the northern Gulf of Mexico, received heavy and prolonged exposure to oil during the Deepwater Horizon oil spill. A NOAA dolphin assessment work slideshow is online here.
NOAA and its state and federal partners are researching multiple ways Gulf dolphins may have been exposed to oil, including through ingestion, inhalation or externally. Dolphins could have routinely ingested oil from sediments or water while feeding or by eating whole fish, including internal organs and fluids such as liver and bile, which can harbor chemical contaminants. These are not likely routes of exposure for most people.
After closely examining 32 dolphins during the past summer, the biologists said they fear many of the dolphins are in such poor health that they will not survive. One of these dolphins, which was last observed and studied in late 2011, was found dead in January 2012.
Along with examining individual dolphins, NOAA, along with state, federal and local partners, also continue to study a string of 675 dolphin strandings in the northern Gulf of Mexico dating back to February 2010 — a much higher rate than the average 74 strandings per year.
As a result, NOAA previously declared an “Unusual Mortality Event,” and is investigation as many of the mortalities as possible. The vast majority of stranded dolphins have been found dead; however, 33 have stranded alive and seven have been taken to facilities for rehabilitation.
NOAA researchers said it’s typical to see some newborn, fetal and stillborn dolphins strand, and there has been an increase in strandings of this younger age class during this 2010 and 2011. Yet all age classes continue to strand at high levels. NOAA is working with a team of marine mammal health experts to investigate the factors that may be contributing to the dolphin mortalities.
Parts of the northern Barataria Basin, a larger area that includes Barataria Bay, remain closed to commercial fishing, as visible oil is still present along the shoreline where the closures are in place. The joint protocol directs seafood safety testing to begin only after visible oil is gone.
Filed under: BP Gulf oil spill, Environment, Marine biology, oil drilling Tagged: | Barataria Bay, Deepwater Horizon oil disaster, Louisiana, National Oceanic and Atmospheric Administration, sick dolphins