This Week @ UCSD
Top Stories Print this story Print Forward to a Friend Forward

Understanding the World's Oceans
Scripps Researchers Travel World to Study Reefs, Fish and Corals

By Ioana Patringenaru | October 9, 2006

They examined coral in Tahiti while the warm waters of the Pacific Ocean gently lapped at their feet. They caught fish on an atoll located 1,000 miles south of Hawaii. They dove off Christmas Island.

It might sound like a vacation to you. But researchers from UCSD’s Scripps Institution of Oceanography actually spent their summer trying to make sure that the rest of us will be able to enjoy the world’s oceans for many years to come.

Stuart Sandin and another scientist work under water.
Click here to view photo gallery.

They wanted to understand how humans impact the oceans. They also were looking for ways to preserve diversity in the oceans and help restore coral reefs to their former glory.

To hear researchers tell it, the world’s oceans are in crisis. About 90 percent of top predators, including sharks and snappers, are gone. Early findings show that fish stocks are dwindling and live corals are shrinking. Meanwhile, pollution has allowed algae to prosper and overrun corals.

“We have the potential to turn crystal-clear coral reefs into a microbial soup,” said Enric Sala, a professor of marine ecology at Scripps.

He and other scientists fanned out across the globe this summer to better understand what has been going on beneath the surface of the seas and what can be done about it.

The Line Islands

A group shot of the team that worked on Palmyra. Walsh is third from the left, with Sala to her right. Sandin is last on the right.
Click here to learn more about Sala and
Sandin's trip to the Line Islands last summer.

A group of researchers visited the Line Islands in the summer of 2005. That trip lead them to question existing data about coral reefs before humans significantly altered them.“The problem is that we began to do the science after humans had done away with top predators in most places,” Scripps researcher Stuart Sandin said. “So our baseline is wrong.”

As a result, existing strategies to manage fish stocks and preserve reefs also are wrong because they’re based on flawed assumptions, Sandin said. Scientists are now trying to answer several questions. What is humanity’s real impact on the world’s oceans? Are we making marine ecosystems less sustainable? And how does that impact economic development on land? 

The Scripps scientists speculated that a healthy – and protected -- reef  could produce more fish. “It looks like in the ocean you can have your cake and eat it too,” graduate student Sheila Walsh said. “This is perhaps the only good news sharks have had in a long time,” Sandin added. 
To find out whether they were right, Sandin, Walsh and about 20 other researchers, including Sala, headed out again to the Line Islands. They picked the island chain 1,000 miles south of Hawaii for further study because of its great diversity. For example, Christmas Island is home to 10,000 residents. The Republic of Kiribati, to which it belongs, wants to double the island’s population in the next decade. By contrast, Palmyra Atoll is a National Wildlife Refuge, where only four researchers live permanently. A little further north, Kingman Reef is virtually pristine. Reefs around undisturbed islands are more beautiful, with more fish and more predators at the top of the food chain. Down the line, in the worst case scenario, algae took over the reefs and the corals are gone.

In coming years, researchers plan to work their way down the island chain, following a trail of human disturbance. They’ll try to puzzle out which conditions lead to more productive reefs. Scientists hope to build a growth chart for these reefs, much like the charts that track a child’s growth over the years, Sandin said.  

Sandin and Walsh spent months planning this summer’s expedition to Palmyra and Christmas Island. They booked cargo flights and shipments on barges and scheduled boat time for dives. They secured hazardous materials permits to ship ethanol and formol to preserve samples.

 “This whole effort is phenomenal,” Sandin summed up.

Walsh, who was in charge of Christmas Island leg of the trip, said she worried about her last shipment. It was scheduled around the same time as the Independence Day celebrations on the island and had to compete with huge amounts of food and alcohol. “Here I am hoping that we won’t get bumped off by food – or beer,” she said.

Finally, in August, researchers flew to Honolulu and from there took a small aircraft and landed on a WWII strip on Palmyra. The atoll is covered in lush forests and is home to one of the few coral reefs almost free of human contact, Sala said. “It looks like a rain forest in the middle of the ocean,” he added.

On Palmyra

A sign at the Palmyra Atoll research station.

Palmyra turned out to be quite comfortable, Sandin said. Researchers stayed in two-person bungalows that faced the lagoon. They could sometimes see baby sharks swimming by, Walsh remembered. Every morning, the cooks, or “galley goddesses” as the scientists called them, cooked up a hearty breakfast. Some researchers then loaded their boats with equipment and diving gear and headed out to sea for four to five hours. Others stayed behind and collected fish with micro spears and nets as well as the good, old-fashioned way: by fishing with a hook and line. After a restorative lunch, scientists headed to the lab around 2 p.m. They ran close to 20 tests on each fish, which took 30 minutes to an hour to process. Most researchers could be found in the lab until midnight or 1 a.m., Sandin said.

Researchers work in the lab at Palmyra.

They caught more than 350 fish on Palmyra, including surgeon fish, snappers, two species of damsel fish, hawk fish and wrasse. They collected tissue samples for DNA analysis. They checked the animals’ condition, including body fat. They looked at what the fish ate. They even came back with scores of fish stomachs in vials. They also looked at whether the fish were healthy and whether they could reproduce. One researcher exclusively looked for parasites. Scientists also managed to do some exploratory dives.

Since the researchers’ trip to Palmyra last year, fish had become much more curious and bolder, Sandin said. One day, he was trying to catch a snapper with a hook and a line, when he felt some resistance — then nothing. He pulled on his line and up came half a fish with a perfect half-moon bite mark on its body. It wasn’t an isolated incident. Snapper and sharks often stole fish that scientists were trying to catch. The sharks were about 4 feet long, Sandin recalls. “They wouldn’t eat you, but they could hurt you,” he said. So researchers made sure they spilled as little blood as possible. They soon gave up on collecting blood-rich groupers, which would need to be brought back to the surface while bleeding profusely.

Christmas Island

Meanwhile, Walsh and three other researchers broke away to spend two weeks on Christmas Island. Sandin said he was concerned about that leg of the trip because researchers would have less control over their working conditions and would need to rely on residents for assistance. Walsh had talked on the phone with officials in the capital of the Republic of Kiribati, but they were about 2,000 miles east of the island where she and the other researchers would land. She also had exchanged some e-mails with a few local people. But once on the ground, she was pleasantly surprised, she said. Their research, she found out, was very relevant to Christmas Island residents. “It’s not just their livelihood,” she said. “It’s the lifestyle.”

Walsh works in the researchers' makeshift lab on Christmas Island.

Still, the four scientists were roughing it when compared to the crew left on Palmyra. Walsh and her colleagues stayed at a private home that had been turned into a hotel. They joined local residents on their early morning stroll. Researchers then picked up their supplies and diving gear. They loaded it onto large canoes and went out to sea. They often ate SPAM sandwiches for lunch. Then they went back out to dive or spent the rest of the afternoon in a makeshift laboratory on the hotel’s patio. They relied on local fishermen for fish samples. Dinner was more inspiring, with local lobster, tuna and other fish on the menu. Researchers also went out at sunset, when many locals would be out fishing on the reef.

Walsh recalls stumbling upon a shark’s carcass, with its fins missing, on the beach. That really brought the consequences of overfishing home to her, she said. The crisis facing the oceans’ top predators also became clear when scientists compared diving conditions on Palmyra and Christmas. “When you dive on Christmas, you feel alone,” Walsh said. Sharks and snappers were rare. But after a while, you start noticing smaller fish, which hover further up on the reef. By contrast, top predators abound in Palmyra, overwhelming the diver’s senses.  Divers can see up to 100 to 150 feet in Palmyra, while on Christmas Island a day with 100 feet of visibility would be exceptional, Sandin said. Waters in Christmas carry 20 times more bacteria than in Palmyra. The good news is that on Christmas’ uninhabited side, the reef looked a little more like Palmyra. Big schools of snappers were swimming about and corals looked healthier, Walsh said.

Coming home

Scripps Around the Globe

Click here to read more about Scripps researchers traveling around the globe in @UCSD, the magazine of the UC San Diego Alumni Association.

On the way home, researchers had to deal with an unexpected hitch. Liquids and flammables had recently been banned from airplane cabins after British authorities foiled a terrorist plot to blow up airliners with liquid explosives disguised as carry-on items. But scientists needed to preserve their samples with ethanol and formol. “We were bringing back liquid samples with flammable or carcinogenic proprieties,” Sandin said. It took a while but he was able to convince the airline to let his cargo through. Luckily, he had all the permits required.

On Christmas Island, Walsh and her colleagues put all their samples in a cooler with ice they made in the hotel’s fridge. In Honolulu, they got dry ice and shoveled it into the cooler.

The samples are now sitting in deep freezers at Scripps. They will be analyzed in labs at Scripps, UC Santa Barbara and in Boston. So do healthy and protected reefs actually produce more fish? Walsh and Sandin said they still believe that’s true. But they now have to wait and see what their data will reveal. Findings should trickle through the academic year, Sala aid.    

Laetitia Plaisance, a French post-doc, is still working her way through 1000 samples that Scripps researcher Nancy Knowlton brought back from Palmyra last summer.


Plaisance, center, with the team manning the research station in Moorea.

Plaisance is taking part in a research project looking at the biodiversity of coral reefs in Panama, Hawaii and Tahiti. She spent two weeks on the small island of Moorea, a few miles from Tahiti’s main island. She was working at a field station manned by UC Berkeley, UC Santa Barbara and University of Florida researchers. She also served as a mentor to a Tahitian student who was gearing up to study for a masters at a French university.

She started work around 8 a.m. in the lab while her colleagues headed out to dive on the reef. They brought back heads of corals, which Plaisance would examine. She cut the corals’ branches into small pieces and looked at the different organisms hidden inside, including mollusks, crustaceans, sponges and algae. She sorted them out by species and took pictures. She went through eight heads of coral during her two-week trip, which yielded around 1000 samples.

“What lives inside these heads is really amazing,” Plaisance said. She found small octopus and all kinds of other creatures. Now back in San Diego, she plans to analyze her samples’ DNA to find out how many separate species she actually brought back.

Boats at the Moorea research station.

 “I’m very happy about it,” Plaisance said. “I think two weeks is too short but it was really good and really interesting.” It was nice to work outside, with her feet in the water of the lagoon all day, she added.

Later this year, Plaisance plans to fly out to Hawaii or Panama to collect more samples. Walsh plans to look at the links between economic development and preservation. She will go around 10 islands and conduct a survey of household incomes and expenditures. Sandin already is thinking about next year’s trip to the Line Islands, which will include Palmyra and Kingman Reef. This summer’s experience left him in awe, he said. Some of the islands lie just 6 feet above sea level and could disappear in a couple of generations as global warming causes water levels rise. “The thought of having a whole island I worked on go extinct is amazing,” Sandin said.

Subscribe Contact Us Got News UCSD News

UCSD University Communications

9500 Gilman Drive MC0938
La Jolla, CA 92093-0938