I felt a pinch on the back of my sunburned legs as I donated yet another meal to a biting fly. Bloodsuckers can be vicious in coastal British Columbia where I usually work. These Panamanian insects and I were getting acquainted for the first time. I was now 6,000 kilometers from home. I was transfixed on a nearby fig tree where a three-toed sloth scratched lethargically at its coarse gray back hair.
Most of the year I help Hakai Institute scientists share their stories in British Columbia. But in mid-March of 2017, I ventured south to the Caribbean coast of Panama to visit the Smithsonian Tropical Research Institute (STRI).
STRI’s research station in Bocas del Toro is part of the Smithsonian Institution’s worldwide network of marine global earth observatories, or MarineGEO. MarineGEO scientists are trying to better understand marine biodiversity patterns and how such diversity maintains resilient coastal ecosystems around the world.
MarineGEO is only a few years old, but already boasts an impressive member list of research stations from Australia to Belize and most coasts in between. And last year, the Hakai Institute’s Calvert Ecological Observatory became the first MarineGEO research site in Canada.
I had a sense of how Hakai’s MarineGEO scientists plied their trade in temperate environs. Now, I wanted to experience firsthand how MarineGEO functioned in the tropics.
I joined MarineGEO postdocs Janina Seemann and Maggie Johnson as they set up experiments at dive sites throughout the Bocas del Toro archipelago. A few weeks prior, I’d been scuba diving in frigid 6°C Canadian waters, clad head-to-toe in neoprene. Here in Panama, I adopted a minimalist ensemble for the balmy 27°C Caribbean waters. Bathing suit. Rash guard. Jump in.
We descended five meters underwater, and swam toward a shallow coral reef. A vibrant blue-and-green parrotfish darted past my fins. An arrow crab waved two spider-like legs at me, as though trying to get my attention.
Different shapes of coral dominated each section of the reef, signifying different species. I noted each using made-up common names, as I hadn’t yet learned their scientific monikers. Deer antlers. Finger nubs. Boulder brains.
Creative use of available materials is an art form in experimental ecology. Seemann carried with her a random assortment of hardware-store items—sledgehammer, arm-length PVC pipes, and a bag of plastic vials.
These materials were part of an experiment to test how much sediment accumulates on these coral reefs. Sediment run-off from land can affect corals by blocking out light, or by stressing the coral polyps, as they constantly have to clean themselves off.
As I floated a few meters away, Seemann put the bag down on the sandy ocean floor next to a field of coral. She planted one end of the PVC pipe in the seafloor and—thwap!—hammered it down. Thwap! Thwap! Thwap!
Soon, just the top of the pipe was visible above the reef. On the protruding tip of the pipe was stretched a black plastic mesh normally used for fencing. That fencing acted as an inventive rack to hold an array of smaller plastic tubes.
Seemann placed one uncapped tube in each fencing hole, effectively suspending a rack of tubes on the seafloor. In two weeks, Seemann and her colleagues would return, cap each tube, bring them back to the lab, and check the sediment in the bottom; an estimate of how much sediment accumulated on the reef over that time.
My curiosity quickly got the better of me. While Seemann swam away to another portion of the reef to hammer in a second pipe, I hung back and investigated a rock lobster holed up under a boulder coral.
I spent my second day in Bocas del Toro deep in another coastal habitat not present in British Columbia—mangroves. These salt-tolerant tree species grow along tropical and subtropical coastlines worldwide. Mangrove trees protect the coastline during storms, act as nursery grounds for important fishery species, and generally add to the resilience of coastal communities.
Our boat motored up to the edge of a small islet covered with a dense mangrove forest. I couldn’t see what lay beyond the dense wall of waxy green leaves.
We hopped out and clambered over arching red mangrove roots coated with spongy brown mosses, branching lichens, and spherical green bubbles of algae. A coffee-colored crab the size of a hockey puck scurried along a mangrove branch above my head. Tree crabs—that was a new one for me.
Joining our group that day was world-renowned mangrove researcher Candy Feller, a senior scientist with the Smithsonian Environmental Research Center. A tour through the mangroves with Feller was like walking through the Louvre with an art historian. She’d stop periodically, pick up a leaf, and share a fascinating morsel about the mangrove ecosystem, such as the finer points of mangrove leaf-miner moths and their oddball larvae.
Step by muddy step, we trudged toward a forest of dwarfed mangroves two hundred meters inland.
“There are sometimes stingrays in here, so watch your step,” Seemann said casually.
I harkened back to my playground days and pretended the mud was lava, while I hopped from root to root with the grace of a cow on a tightrope. I slipped, both feet splattering into the oozing mud. Mangrove root balance beam is not my best sport.
Our sight lines opened up as we reached a football-field-sized expanse of waist-high trees. Mangroves don’t have rings in the trunk that you can count to determine their age. But each year two new leaves are formed on the stem as the tree grows. The older leaves lower down the stem fall off and leave a notched scar. So by counting the number of scars, Feller deduced the tree’s age.
Mangroves forests become shorter as you move inland. The largest trees often grow at the outside edge and take up the bulk of the nutrients flooding inward with the tides. These inner mangroves only receive the leftovers, hence their small stature.
“Look at how many scars there are! These tiny trees are a few hundred years old,” said Feller.
We were here to measure the mangroves; both the trees’ diameter and height, and also the area covered by their strange amphibious root systems.
“Mangroves will keep pace with sea level rise if it happens slowly,” said Todd Osborne, a visiting scientist from the University of Florida. “But a big increase in the rate of sea level rise would overwhelm them.”
Mangroves are one of the coastal habitats being intensively monitored by MarineGEO scientists to track changes over the short- and long-term. These measurements will help scientists understand how mangrove habitats will be altered by climate change.
As my time in Panama drew to a close, and I started to get insect bites on top of my insect bites, I reflected on my time in the tropics. Though Canada lacks mangroves and coral reefs, the oceans from pole to pole are being altered by climate change. The pace of climate change makes the coordinated efforts by MarineGEO sites around the world all that much more critical.
Back in British Columbia, scientists will gather in late July and early August for the inaugural Hakai MarineGEO bioblitz. Experts from around the world will search a variety of coastal ecosystems around the Calvert Island Ecological Observatory, including seagrass meadows, kelp forests, soft sediments, and the rocky intertidal.
A comprehensive survey of one of the most biodiverse temperate marine regions in the world is sure to turn up some ecological surprises. There won’t be any sloths, but I can promise biting insects to make everyone feel at home.