The last time I reported on the Conservation of Neotropical Snakes project in Brazil, I had just come back from the Queimada Grande Island, or the Snake Island. The golden lancehead project is going very well and we are gathering valuable information about the feeding strategies, mating system, and ecological requirements of this endangered snake.
Another field site we visit regularly is a patch of the Atlantic rainforest in Brazil, which has the largest biodiversity in the entire world, with some areas even richer in species than the Amazon forest. During our last trip, my four students and I found ourselves near a small, natural pool surrounded by rainforest with no less than 25 species of frogs calling! It was the perfect open-air classroom to teach frog taxonomy and behavior, conservation biology, and amphibian reproductive physiology.
The place was a diverse orchestra and sometimes I thought my ears would explode, so loud were the calls of hundreds of individual frogs from water level to the highest tree branches.
As expected, the place was also an all-you-can-eat buffet for snakes, and in less than 25 feet walking we had captured four snakes. Can you imagine yourself walking slowly between bushes in water up to your knees, with a loud frog orchestra, dark sky with full moon, mosquitos also dining on you in their own blood-fed buffet, and beautiful bright yellow water snakes crawling and swimming everywhere? Perhaps not everyone’s dream trip, but for us it was magical.
The snakes we captured were marked and measured, and we collected blood samples for health screening exams as part of our project with San Diego Zoo Global.
In this region it is common to see snakes along the crop plantations. The people here are very afraid of snakes in general, but we are teaching them that snakes are essential to the health of the ecosystem, are animals like any other, and should be respected rather than feared. Before our expedition ended, I got some gratifying feedback from one farmer who used to kill every snake that came his way.
He explained that he started to feel bad killing snakes and he even started to see some beauty in them. He is still afraid of snakes, especially the venomous ones, but his feelings are turning into compassion for animals that have long evolved and established their home in the tropical forest.
Unfortunately, the tropical forest is also a good place to plant crops in Brazil, so snake-human conflict is unavoidable. Our goal is to change the way people see the snakes in order to preserve snakes and their habitat while maintaining the rights of people who work on the land.
Today, I have even more good news! Our captive population of the critically endangered golden lancehead will increase this year. A female that mated last July is gravid (pregnant) and her last prenatal ultrasound test revealed five fetuses! Golden lanceheads are not a very prolific species, unlike another Brazilian viper the jararacussu, which can deliver up to 73 little vipers in a clutch. Snakes are very important to control rodent populations, so a female jararacussu is doing her best to keep rodents under control in nature.
On the other hand, golden lanceheads feed on migratory birds that visit the Island, so food is a scarce resource for them. Our studies indicate that a female lancehead probably survives by feeding on less than ten birds per year, so her reproductive rate is understandably lower than her more voracious relative. I will share photographs of our baby golden lanceheads soon!
Rogerio Zacariotti, D.V.M., Ph.D., Field Biologist