Brazil's Ilha de
Queimada Grande is the only home of one of the world's deadliest, and most
endangered, snakes
 |
| University of Sao Paulo researcher Marcio Martins holds one snake while watching another, a deadly venomous snake living only on Queimada Grande Island, Atlantic Forest, Brazil. (© Mark Moffett/Minden Pictures/Corbis) |
From Iguazu Falls to Lençóis
Maranhenses National Park, there are some breathtakingly beautiful places
in Brazil. Ilha da Queimada Grande, located about 90 miles
off the São Paulo coast, seems like another one of those beautiful
places—at first glance. Almost every Brazilian knows about the
island, but most would never dream of going there—it's infested with
between 2,000 and 4,000 golden lancehead vipers, one of the deadliest
snakes in the entire world.
These vipers' venom can
kill a person in under an hour, and numerous local legends tell of
the horrible fates that awaited those who wandered onto the
shores of "Snake Island." Rumor has it a hapless
fisherman landed onto the island in search of bananas—only to be
discovered days later in his boat, dead in a pool of blood, with snake
bites on his body. From 1909 to the 1920s, a few people did
live on the island, in order to run its lighthouse. But according to
another local tale, the last lighthouse keeper, along with his entire family,
died when a cadre of snakes slithered into his home through the windows.
 |
| Ilha de Queimada Grande, the golden lancehead is unique to this island |
Although
some claim the snakes were put on the island by pirates hoping to protect
their gold, in reality, the island's dense population of snakes evolved
over thousands of years—without human intervention. Around 11,000 years ago, sea levels rose enough to
isolate Ilha da Queimada Grande from mainland Brazil, causing the species
of snakes that lived on the island—thought to most likely be jararaca snakes—to
evolve on a different path than their mainland brethren.
The
snakes that ended up stranded on Ilha da Queimada Grande had no ground
level predators, allowing them to reproduce rapidly. Their only challenge:
they also had no ground level prey. To find food, the snakes slithered
upward, preying on migratory birds that visit the island
seasonally during long flights. Often, snakes stalk their prey,
bite and wait for the venom to do its work before tracking the prey
down again. But the golden lancehead vipers can't track the birds they bite—so
instead they evolved incredibly potent and efficient venom, three to five
times stronger than any mainland snake's—capable of killing most prey (and
melting human flesh) almost instantly.
 |
Ilha
da Queimada Grande looks very pretty from far away—but terrifying up close.
|
Because
of the danger, the Brazilian government strictly controls visits to Ilha da
Queimada Grande. Even without a government ban, though, Ilha da Queimada Grande
probably wouldn't be a top tourist destination: the snakes on the island exist
in such a high concentration that some estimates claim that there's one snake
for every square meter in some spots. A bite from a golden lancehead carries a
seven percent chance of death, and even with treatment, victims still have
have a three percent chance of dying. The snake's venom can cause kidney failure, necrosis of muscular tissue,
brain hemorrhaging and intestinal bleeding.
The
Brazilian government requires that a doctor be present on any legally
sanctioned visits, in the event of an unfortunate run-in with the island's
native population. The Brazilian navy does make an annual stop on
the island for maintenance of the lighthouse, which, since the 1920s, has
been automated. The island is also an important laboratory for biologists and
researchers, who are granted special permission to visit the island in order to
study the golden lanceheads.
 |
|
Female golden lancehead, coiled in a tree |
Ninety
percent of snake bites in Brazil come from lancehead snakes, a close cousin of
the golden lancehead. (Both are members of the Bothrop genus.) Biologists hope
that by better understanding the golden lancehead and its evolution they
can better understand the Bothrop genus as a whole—and more
effectively treat the numerous snake-related accidents that occur throughout
Brazil. Some scientists also think that snake venom could be a useful tool in
pharmaceuticals. In an interview with Vice, Marcelo Duarte, a scientist with
the Brazilian Butantan Institute, which studies venomous reptiles for
pharmaceutical purposes, described the medical potential of the golden
lancehead. "We are just scratching this universe of possibilities of
venoms," he said, explaining that the golden lancehead's venom has already
shown promise in helping with heart disease, circulation and blood clots. Snake
venom from other species has also shown potential as an anti-cancer drug.
 |
|
Adult
male golden lancehead, coiled |
Because
of black market demand by scientists and animal collectors, wildlife smugglers, known as biopirates, have been
known to visit Ilha da Queimada Grande, too. They trap the snakes and
sell them through illegal channels—a single golden lanceheads can go
for anywhere from $10,000 to $30,000. Habitat degradation (from removal of
vegetation by the Brazilian navy) and disease have also damaged the
island's population, which has dwindled by nearly 50 percent in the
last 15 years, by some estimates. The snake is currently listed
as critically endangered on the International
Union for Conservation of Nature's Red List. While that might make Snake
Island slightly less terrifying for humans, it's not a great deal for the
snakes.
|
Kingdom
|
Animalia
|
|
Phylum
|
Chordata
|
|
Class
|
Reptilia
|
|
Order
|
Squamata
|
|
Family
|
Viperidae
|
|
Genus
|
Bothropoides
|
Nenhum comentário:
Postar um comentário