Brazil’s Golden Lancehead: A Treasure to be Protected

Soon I’ll be returning to a spectacular island off the coast of São Paulo State in southeastern Brazil to continue my studies as a field researcher for the San Diego Zoo Institute for Conservation Research. But before you rush to sign on as a field assistant, let me explain the logistics of the trip and warn you of some surprises we might encounter along the way. 

We will travel to the island on a fishing boat, not a yacht, and the seas can be as rough as scenes from the movie Pirates of the Caribbean. Our destination is the Queimada Grande Island, a real paradise if you are a herpetologist interested in conservation of endangered reptiles. The small island (106 acres) is home to a population of 2,000 critically endangered pit vipers, the golden lanceheads.

This beautiful tan-colored Brazilian snake is endemic to Queimada Grande Island, where its population has declined by 50-percent in the last 15 years. Habitat degradation, illegal animal trade, and disease all contribute to this population’s dramatic decline. My study is focused on documenting threats to the species and developing a plan to reverse the downward trend.

After we carry about 450 pounds of field equipment and supplies uphill to the campsite, we prepare for a week of trekking over the island in search of the elusive lancehead. Starting in the bushes directly behind our camp tent, we move cautiously along the trail looking for the scaled residents.

If we’re lucky, we’ll see the beautiful, healthy female found during our last trip. She was hunting for birds, the species’ major prey, in a bush 16 feet from our campsite. Each time our team finds a snake, we must approach very carefully because this venomous creature is quite shy and easily startled by humans. If we frighten the snake away, we lose crucial information about how the animal uses its habitat during its normal routine of resting or hunting. 

If all goes well, we collect habitat information, including the type of vegetation the snake prefers, the temperature and humidity, and the behaviors exhibited by an undisturbed animal. Once these data have been recorded, we carefully capture the snake using long tongs to avoid injury (to the snake and to ourselves!). After a brief health exam, blood, tissue samples, and ticks are collected, and a microchip is implanted to permanently identify the individual. If our quarry is an adult female, we perform an ultrasound exam to monitor the reproductive cycle by visualizing ovary development and the presence or absence of gestating young.  If we capture a male, semen is collected for evaluation.

After an 8-hour hike across the island, we will capture between 5 and 13 snakes, a very impressive number! At our other field sites in the Atlantic rain forest and the Brazilian savannah, we might devote 10 hours to finding a single snake. Back at the camp we catalog samples and examine the blood for signs of parasites, anemia, or chronic infection. Luckily, there is always a stray candy bar nearby to help replace the calories lost in the field before we start the lab work. 

Exhausted after seven straight days of long hours and miles of trudging across the island, we head back to the mainland. Each time we leave, we relish the memories of our days in the field, like the time I found a worm lizard digging in the dirt at my feet. This species had not been seen for decades!

We may see whales, dolphins, and penguins on the trip back to civilization, and, despite the hardships of the field, we are exhilarated by the knowledge we have gained and the progress we’ve made toward saving the unique golden lancehead in its native habitat.

Rogério Loesch Zacariotti, D.V.M., MsC, Ph.D.  He is a field researcher for the San Diego Zoo Institute for Conservation Research and an assistant professor at of Animal Reproduction and Wildlife Medicine at Cruzeiro do Sul University in Sao Paulo, Brazil.