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The dock at STRI's Bocas del Toro research station. Photo by Megan Gambino.

ATM blogger Megan Gambino spent a week in Panama reporting on research taking place at two locations—Barro Colorado Island and Bocas del Toro—of the Smithsonian Tropical Research Institute (STRI). Read on to follow her day-to-day adventures.

Day 3: Arriving at Bocas

Today I left Panama City for Bocas del Toro, a town on Isla Colon, a 24-square-mile island on Panama’s Caribbean coast just 22 miles south of the Costa Rican border and an hour’s flight from the capital. Just outside of Bocas town is another of STRI’s research stations, where I will be staying for the next four days to report a story on a mass coral spawning that happens every year just days after the September full moon.

Since 2000, coral reef biologists Nancy Knowlton, the Smithsonian’s Sant Chair of Marine Science; Don Levitan of Florida State University; and a team of research divers have been studying the spawning of the Montastraea annularis complex—three closely related species once thought to be one and the same—here in Bocas.

Just off the coast of Solarte Island (one of the other 68 islands and mangrove keys in the archipelago)—about a 20-minute boat ride from the station—they’ve marked an 80-meter arc of coral reef with nine underwater buoys that they light at night with green glow sticks. Over the nine years of the project, they have tied pink flags to coral colonies they have witnessed spawn. (The outermost layer of coral is a community of living animals that eat, reproduce and die, thus making up the foundation of the rocky substrate of the reef.)

Each colony is also numbered with a blue metal tag and all have been mapped and genetically analyzed and identified. The researchers have found that M. franski, one of the species, spawns on average 100 minutes after sunset, typically five or six days after the full moon. The other two, M. annularis and M. faveolata, spawn about 200 minutes after sunset. The colonies use the lunar and sunset cues, and most likely a chemical cue (it’s possible they smell each other spawn), to synchronize their spawning. The latter two species cannot cross-fertilize, but M. franski and M. annularis are reproductively compatible. So the researchers have been studying what reproductive barriers or ecological conditions are in play that prevent hybridization. Also, they’re beginning to wonder, if reproductive success depends on mass spawning, then what will happen as coral reefs become few and far between as a result of the damaging effects of climate change and human development.

Wetsuits hanging to dry outside STRI's dive locker. Photo by Megan Gambino.

The team was gearing up for its first night dive. In years past, they have found that a few colonies typically jump the gun and spawn early. The group spent the morning making sure the tags on the coral were visible, while I snorkeled above to get my bearings of the study site. The next time I’d be there I’d only have a flashlight and the green glow sticks on the buoys to orient myself!

At about 5 p.m., six divers and I gathered in the lab to hear Don’s instructions. The dive team would be making two back-to-back dives, one in timing with when M. franksi spawns and the other when M. annularis and M. faveolata do. The operation was impeccably organized, like a coral raid. Armed with red glow sticks, the divers were told to crack and place them on setting corals, or corals that became pimpled with gamete bundles almost ready to be released. They were to record set and spawn times on waterproof slate boards. (On average, spawning happens about 20 minutes after the coral sets.)

In the boat, “Team Spawn,” as Don jokingly named the divers, synchronized their watches and donned life vests. At the site, we waited for sunset and then all of us made our way to the lit transect by 7:45 p.m. Pairs of divers were assigned to scan certain sections of the marked reef for setting and spawning corals, and I snorkeled above to observe.

It was my first-ever night snorkel, and it was such a different experience. At first, just having my light and the lights of the divers to follow was unnerving, but I settled into it. With their lights cast downward, the dark silhouettes of the divers made them look like aquanauts. The whole landscape was otherworldly.

When I shut off my flashlight, flipped my fins and waved my hands through the water, bioluminescence kicked up like fireworks around me. I could hear Latin music blaring from the nearby town of Bastamentos whenever I lifted my ears above the surface, and the combination of the bioluminescence, music and glow sticks created this rave-like quality—surely, I thought, a fitting scene for a coral orgy.

But no such luck. M. franksi, the early spawner of the group, held off, meaning the later spawning species would too, and so we returned to the boat, canceling the second dive. Maybe tomorrow night….

The personalized gear of Elizabeth Kalko, right, one of the foremost authorities on bats. Photos by Megan Gambino

ATM blogger Megan Gambino is spending this week in Panama reporting on research taking place at two locations—Barro Colorado Island and Bocas del Toro—of the Smithsonian Tropical Research Institute (STRI). Read on in this dispatch and in future installments to follow her day-to-day adventures.

Day 1, Part 2: A Visit to Bat Cove

Elisabeth Kalko, one of the foremost experts on bats, spends two months a year, usually March and sometime between July and October, conducting research at Barro Colorado Island. Luckily, I managed to catch her there just before she planned to head back to Germany, where she is the head of the experimental ecology department at the University of Ulm. And I couldn’t pass up her offer to take me out to “Bat Cove,” just a five-minute boat ride from BCI.

We left just before sunset and anchored in the cove. On the edge of the forest, Elisabeth explained, there is a 65-foot-tall hollow tree where Noctilio leporinus, the only bat on the island with fish as its primary diet, has a roost. Also known as the greater bulldog bat, Noctilio swoops down over the water, snatching fish in its talons. Apparently, it curls its head down to grab the fish to eat, chews it and fills its cheek pouches like a hamster. Elisabeth and a grad student working with her set up their echolocation recording equipment in the boat as we waited for dark to set in and the first bats to start foraging.

Elizabeth Kalko, photo by Megan Gambino

To put things in perspective, there are 1,100 species of bats in the world. Around 120 (over a tenth of those worldwide) live in Panama, and of those, 73, ranging in size from three grams to the notorious vampire bat that’s the size of a small puppy, can be found on BCI.  Elisabeth has worked closely on understanding the behaviors of a quarter of the 73 and probably observed 60 of them. Her interest is the various foraging strategies and other behaviors that have allowed so many species to coexist. In her research, she has found bats that live in termite nests; bats off the coast of Baja, Mexico, that forage miles into the ocean; and bats that use echolocation to find stationary prey, like dragonflies perched on leaves.

Elizabeth had a bat detector with her on the boat that could pick up the high frequency echolocation calls of nearby bats and make them audible. Slowed down, the calls sounded like the chirps of birds, and Elizabeth can recognize the species from the frequency and pattern of the calls. The chirps would come in loud on the detector, and her research assistant would cast his headlamp across the surface of the water. “Wah!” Elisabeth would exclaim as one flitted by the boat.

In the beginning, several circled the area. But as the night wore on, the activity calmed down, mostly because it was just a day or two after the full moon, and bats don’t like that much moonlight; most insects don’t come out then. It was certainly a surreal experience. I think Elisabeth put it best when, perched on the bow of the boat, looking up at the moon, she said, “So many billions of people in the world are doing the same thing, day in and day out. But we three are the only people out here, looking for fishing bats.”

An agouti, a small rodent that is related to a guinea pig, makes a surprise appearance during Megan's tour of the forest at STRI. (Photo by Megan Gambino)

ATM blogger Megan Gambino is spending this week in Panama reporting on research taking place at two locations—Barro Colorado Island and Bocas del Toro—of the Smithsonian Tropical Research Institute (STRI). Read on in this dispatch and in future installments to follow her day-to-day adventures.

Day 1: Trekking around Barro Colorado Island

After arriving in Panama City last night, I woke up early this morning and drove 40 minutes north out to Gamboa. The further I got from the city, the denser the forest seemed to grow. The transition was quite remarkable. The leaves got bigger and bigger—palm fronds drooping under their weight and fern-like leaves seemingly on steroids. It reminded me of what I had read in Elizabeth Royte’s book The Tapir’s Morning Bath just days earlier: “Here things got large, even unseemly: flower petals the size of cake plates, beetles like grenades, leaves as long as coffee tables.” Gamboa, a Smithsonian Tropical Research Institute outpost, is flanked by Soberania National Park and the Panama Canal. About 3,000 people called Gamboa home in the mid-20th century. But now the population hovers around 300, half STRI employees and half canal workers. Just beyond the town, STRI has a dock, from which they ferry researchers and visitors about 40 minutes further up the canal to Barro Colorado Island.

Once on the ferry, it was the passing freighters that were gargantuan, disproportionately tall compared to the width of the canal. Needless to say, they dwarfed our little tug. But we motored along until, around a bend, yellow stucco buildings with red roofs came into sight.

The yellow stucco buildings with red roofs is home to the Smithsonian's Panama research facility, the Smithsonian Tropical Research Institute. Photo by Megan Gambino

Situated on a hillside in a quiet cove, the field station attracts researchers from all over the world who want to study the rich biodiversity of the nearly six square mile Barro Colorado Island. (Close to half of the 220 mammal species in Panama live and reproduce in Barro Colorado Island, as well as one-tenth of the world’s bats.) To provide a quick history of the island, in 1912, the construction of the Panama Canal caused the Chagres River to rise, forming Gatun Lake and isolating the island. Eleven years later, a group of scientists convinced the governor of the Canal Zone to declare the island a biological reserve. In 1940, the U.S. Congress took control of it, and by 1946, the Smithsonian Institution became its official steward. STRI, the research station, really got off the ground in 1966. Since then, it has grown into a mini campus complete with offices, dorms, a dining hall and a visitors’ center. Researchers flock there for the biodiversity, of course, as well as the access to technology (there are seven radio towers on the island that track tagged animals) and posh (well, for field stations) accommodations.

The first person I met up with on the island was Robert Horan, a researcher from the University of Georgia, who will be working at BCI for six months to track tree frogs. He offered to guide me on a walk through the forest, and we hiked a figure eight on the trails in the northern part of the island. I saw evidence of the research being done on the island—leaf nets collecting falling leaves and fruit so that scientists can better understand the pollination schedules of little-known trees; a radio tower that collects data from tagged ocelots, agoutis and other animals; cages set as traps for ocelots in order to tag them; and heat and motion activated cameras. Hoots, chirps and howls filled the humid, earthy air, and it seemed like there was a surprise—agoutis, howler and spider monkeys, lizards, tamarin, stingless bees, land crabs and crested guan—lurking around every corner.

The two and a half hour hike, in which we spent some time wandering off trail, was certainly not the 10-cent tour, which I appreciated. Robert agreed with me: you really need to get out and sweat to write a story.

Scientists have excavated hundreds of 20-million-year-old fossils at the Panama Canal expansion sites. (Courtesy of STRI.)

There was a time when North and South America did not share a land border. Instead, a large river separated the two land masses. The animals and plants on the continents kept to themselves mostly, with the exception of the birds that refused to call any one place home.

Then, 15 million years ago, the North and South collided, volcanoes erupted and the Atlantic was separated from the Pacific. About 12-million years later, a land bridge formed between the two continents, and the animals and plants began to travel freely.

This land bridge formation occurred near the site of today’s Panama Canal, which makes the area an attractive site for paleontologists who want to learn the continental origins of individual species. Thousands of fossils, ripe for analysis, lie in the canal walls. But the scientists who want them must act fast. The Panama Canal widening project, due to be completed in 2011, has already removed 10-million cubic meters of earth, with more to come.

Teeth belonging to the three-toed browsing horse were unearthed in a Panama Canal widening site. Proof that the horse's range expanded from South Dakota to Panama 15-to-18 million years ago. (Courtesy of STRI)

Smithsonian researchers are now trying to stay one step ahead of the bulldozers. Working in collaboration with the University of Florida and the Panama Canal Authority, the scientists move in, following dynamite blasts, to map and collect fossils. As of last July, 500 fossils, from rodents, horses, crocodiles and turtles, some dating back 20-million years, have been uncovered.

“We expect the fossils that we have been salvaging to resolve some major scientific mysteries,” says Carlos Jaramillo, a Smithsonian Tropical Research Institute scientist. “What geological forces combined to create the Panama land bridge? Was the flora and fauna in Panama before the land bridge closed similar to that in North America, or did it include other elements?”

At least one answer to Jaramillo’s second question has already been found. Aldo Rincon, a paleontology intern, unearthed a set of fossilized chops belonging to the three-toed browsing horse, known to have grazed in Florida, Nebraska and South Dakota between 15-to-18-million years ago.

According to Beth King, the Institute’s science interpreter, (who was recently featured in a Scientific American podcast), the presence of this horse in Panama significantly extends the southern tip of its range from previous finds, supporting the hypothesis that the habitat was probably a mosaic of relatively dense forest and open woodlands.

There are many more fossils to be found at the Panama Canal widening site, and King expects there to be many papers published within the next five years regarding their significance.