How will global warming affect marine food chains?
February 17, 2008
Gretchen Hofmann, associate professor of biology at the University of California at Santa Barbara, said that pteropods, tiny organisms that play a critical part in marine ecology, are likely to suffer from higher carbon dioxide levels in the world's oceans. When carbon dioxide dissolves in seawater it makes increases acidity by stripping out carbonate ions, which are essential for marine organisms like pteropods to build calcium carbonate shells and exoskeletons.
"These animals are not charismatic but they are talking to us just as much as penguins or polar bears," said Hofmann. "They are harbingers of change. It's possible by 2050 they may not be able to make a shell anymore. If we lose these organisms, the impact on the food chain will be catastrophic."
The loss of these small organisms would have a disastrous impact on predators -- including salmon, mackerel, herring, cod -- that rely on them as a food source and could spell trouble for other species.
The pteropod or sea butterfly is one marine organism that could suffer in more acidic seas. A recent experiment by Victoria Fabry at California State University San Marcos found that the shells of pteropods, when subjected to conditions as projected by the model for the year 2100, rapidly dissolved. Photo courtesy of USGS.
"These observations suggest that the double jeopardy' situation —— warming and acidifying seas —— will be a complex environment for future marine organisms," she said.
Warming could bring sharks to Antarctica with devastating ecological consequences
Global warming could make the waters around Antarctica hospitable to sharks for the first time in 40 million years. Their return could have devastating ecological consequences report researchers from the University of Rhode Island.
This article is based on a news release from UCSB