Times of the Islands Spring 2023

green pages newsletter of the department of environment & coastal resources
At first I wondered if I was looking at some kind of
garbage, or perhaps the remnants of some long-lost civilization.
I later learned I’d stumbled upon 925 of the
largest Reef Balls in the world, each nearly as tall as I
am and weighing around 5,000 pounds. These aren’t the
only artificial reef structures to have been built in the
Turks & Caicos—over the last three decades, countless
Reef Balls have popped up all over TCI to create new coral
habitat and aid existing natural reefs.
Reef Balls were news to me, but the plight of coral
worldwide was not. Reefs everywhere have been struggling
under various (mostly anthropogenic) stresses:
overfishing, pollution, habitat destruction, climate
change. Nearshore reefs are under even more pressure
from hundreds of thousands of tourists each year, who
cause inadvertent damage by standing on corals, leaving
behind trash, or wearing toxic sunscreen.
The loss of our reefs would be a tragedy to anyone
who, like me, has experienced the wonder of watching
fish in their natural habitat through a pair of snorkel goggles.
But sadly, if humans cause reefs to go extinct, that
would be the least of our worries. Reefs buffer coastlines
from storms, provide jobs through fishing and tourism,
and support thousands of species of fish, many of which
are key sources of food for coastal communities. Losing
coral reefs would mean losing food, income, and protection
for roughly half a billion people—including many in
the Turks & Caicos. It is clearly in our best interest, not
just Mother Nature’s, to do what we can to protect coral
reefs. The Reef Balls are one of several ways scientists are
tackling this challenge.
While I was excited to see these Reef Balls in action,
I was also curious. As a former materials engineer,
I’m familiar with the harshness of the marine environment.
Few materials can withstand the corrosive salt
water for long; most will start to disintegrate after a few
years, leaching chemical and particulate pollution into
the ocean. Seeing the vast rows of Reef Balls outside
Malcolm’s Road Beach, I wondered how they were built
to help the environment without causing more harm. The
answer turned out to be a relatively simple design—but it
took a few decades to figure out.
Although ancient hunters experimented with the
first artificial reefs as a way of luring more fish to their
nets, using them for eco-friendly purposes was mostly
a 20th-century idea. People started to notice how shipwrecks
evolved into flourishing man-made reefs, and they
got the idea to kill two birds with one stone by dropping
garbage into the ocean.
Florida’s Osborne Reef is a prime example: In the
1970s, a huge effort was undertaken to “recycle” over
a million car tires by turning them into coral habitat.
Unfortunately, what was meant to become the world’s
longest artificial reef ended in ecological disaster. We
learned the hard way that reefs couldn’t be built from
just anything. Tire rubber, for example, doesn’t have the
right surface texture to allow coral larvae to attach, and
it’s too lightweight to stay in place over many years. All
the tires managed to grow was algae, and they floated
away after the first storm, creating a massive pollution
problem that’s still being cleaned up 50 years later.
Since then, scientists have learned how to build successful
artificial reefs. This means using marine-safe
materials that can stand the test of time in salt water,
such as steel (what most shipwrecks are made of), glass,
and cement. Dumping glass bottles and cinderblocks
won’t work—these structures must be large and heavy
enough to prevent movement during storms. They must
have enough surface texture to promote coral attachment,
and enough nooks and crannies to encourage fish
to take shelter.
The Reef Balls, devised by the Reef Ball Development
Group, are made from concrete with a pH similar to seawater,
which prevents the balls from decaying. They’re
expected to last 500+ years underwater! The concrete’s
texture and chemical makeup mimic natural coral limestone,
making it an ideal place for coral to attach and
grow. It’s also easy to mold into the shapes needed for
a successful artificial reef. Reef Innovations built and
installed all of the Reef Balls around TCI, including the
aptly named “goliath” model at Malcolm’s Road Beach.
They make many other sizes and shapes of concrete
reef structures, some as small as nine inches high—but
their weight distribution keeps them in place even during
storms, and their hole patterns are designed so that
rough seas actually push the Reef Balls further into the
sand.
Some Reef Balls are installed with coral fragments
transplanted from imperiled reefs. Others rely solely on
“natural recruitment,” meaning they bide their time on the
sea floor until coral larvae, drifting past in the current,
latch on. Natural recruitment is understandably a slower
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