Scientists link oil spill to drop in fish survival
Source: Associated Press
Federal scientists have determined that extremely low levels of crude oil spilled by the Exxon Valdez caused heart problems in embryonic fish.
In a study published Tuesday in the online journal Scientific Reports, researchers from the National Oceanic and Atmospheric Administration found that embryonic herring and salmon exposed to low levels of crude oil developed misshapen hearts.
"Metabolically, they're different," said John Incardona, a research toxicologist at the Northwest Fisheries Science Center in Seattle. "They can't grow as well. They can't swim as fast."
The defects and subsequent vulnerability may explain why the herring population crashed several years after the spill in Alaska's Prince William Sound and has not recovered, scientists said.
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Read more: http://www.arkansasonline.com/news/2015/sep/09/oil-linked-to-trouble-with-fish-embryos-1/
bananas
(27,509 posts)Very low embryonic crude oil exposures cause lasting cardiac defects in salmon and herring
John P. Incardona
, Mark G. Carls
, Larry Holland
, Tiffany L. Linbo
, David H. Baldwin
, Mark S. Myers
, Karen A. Peck
, Mark Tagal
, Stanley D. Rice
& Nathaniel L. Scholz
Scientific Reports 5, Article number: 13499 (2015)
doi:10.1038/srep13499
Received:03 March 2015Accepted:28 July 2015
Published online:08 September 2015
Abstract
The 1989 Exxon Valdez disaster exposed embryos of pink salmon and Pacific herring to crude oil in shoreline spawning habitats throughout Prince William Sound, Alaska. The herring fishery collapsed four years later. The role of the spill, if any, in this decline remains one of the most controversial unanswered questions in modern natural resource injury assessment. Crude oil disrupts excitation-contraction coupling in fish heart muscle cells, and we show here that salmon and herring exposed as embryos to trace levels of crude oil grow into juveniles with abnormal hearts and reduced cardiorespiratory function, the latter a key determinant of individual survival and population recruitment. Oil exposure during cardiogenesis led to specific defects in the outflow tract and compact myocardium, and a hypertrophic response in spongy myocardium, evident in juveniles 7 to 9 months after exposure. The thresholds for developmental cardiotoxicity were remarkably low, suggesting the scale of the Exxon Valdez impact in shoreline spawning habitats was much greater than previously appreciated. Moreover, an irreversible loss of cardiac fitness and consequent increases in delayed mortality in oil-exposed cohorts may have been important contributors to the delayed decline of pink salmon and herring stocks in Prince William Sound.
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newfie11
(8,159 posts)We are slowly (but speeding up) the destruction of life on this planet.
RR2
(87 posts)God is punishing those fish for being gay or colored or something! Heresy I am telling you, has to be.