Coral killed in Philadelphia lab to test ability to survive
PHILADELPHIA — In a cold room at Temple University, in landlocked Philadelphia, finger-size fragments of coral bathe in four small tanks of seawater. The white skeletons look dead or bleached — but they are not. Healthy animals reside within these hard bodies. Some wave their tentacles from holes in the gnarled stems, like flowers at a mermaid’s wedding.
Alexis Weinnig, a graduate student in the lab who has ushered the corals on their journey, said they are happy today but happier in their home tank, then apologizes for making them sound so human.
“We get really invested in them,” said Weinnig. “And then we kill them.”
Humans are pretty good at killing corals. Over the past 30 years, overfishing, pollution and climate change have knocked out about half the shallow-water reefs on the planet.
But much less is known about how humans are influencing reefs in the deep sea, where slow-growing, cold-water corals might make up two-thirds of all coral species. Add the threats of offshore drilling and trawling, and deep-sea corals might be just as threatened as shallow A healthy coral sample sits in an aquarium at Temple University. The “super corals” build huge reefs in cold waters around the world, sometimes as deep as 3,280 feet below the surface, supporting often large systems of marine life.
water corals.
The tentacled niblets being studied in this cold room are Lophelia pertusa. These widely abundant “super corals” build huge reefs in cold waters around the world, as deep as 3,280 feet below the surface. They support as much biodiversity as tropical reefs and are home to brittle stars, octopuses, sharks, crabs and fish.
Erik Cordes, a deep-sea ecologist who leads the lab at Temple, has found that Lophelia are better at withstanding industrial and climatic stressors than other deep-sea corals, and in some places more than others. Populations in the Gulf of Mexico survive life at the edge of some of the harshest conditions, near natural methane seeps and in slightly higher temperatures with lower oxygen concentrations and higher acidity levels. They might adapt to changes, too.
But Cordes and Weinnig want to know just how much Lophelia can take.
The survivors of today’s death match will be candidates for unprecedented efforts to restore deep-sea environments affected by the Deepwater Horizon oil spill in 2010. Their results will also help inform future efforts to conserve vast areas of the deep sea.
“Lophelia is sort of our lab rat,” said Cordes. It is charismatic, survives in extreme conditions and yet could die from even the slightest changes.
“Now that we understand something about how it responds to climate change, we want to know how does it respond to oil spills, and how will it respond to future oil spills under climate change?”