Tagging a Black Caiman
This originally appeared as a blog post on the Discover Guyana website.
You have to wait until dark. Then you walk down to the river with your group, your guide and the black caiman research team. You board your boats—you notice the bow of the researchers’ boat has been reinforced with sheets of steel—and launch into the black water. Your caiman tagging adventure has begun.
As a guest of the Caiman House Lodge, you have the rare opportunity of witnessing first-hand research scientists as they go about the job of capturing, measuring and tagging black caiman—the largest member of the Alligatoridae family--in the wild.
Located in the village of Yupukari in central Guyana, Caiman House Lodge and Research Station is a non-profit organization owned and operated by the indigenous villagers. In addition to the black caiman, the Research Station studies and cares for populations of yellow spotted Amazon turtles, jaguars and more.
As darkness settles on the Rupununi River, the creatures of the night begin to stir. Riding in your boat, you may be able to see tree boas, iguanas, frogs, and many fish species (i.e arawana, piranha). You look for sleeping birds (Kingfishers, small perching birds) Nightjars, Potoos, Boat-Billed Herons and other aquatic birds, bats, (harmless) spiders, insects, moths, and more. If you’re lucky, you might even catch a glimpse of possums, capybara, and sleeping monkeys.
The research team patrols the river banks with a bright, hand-held spotlight, looking for the reflection of a black caiman’s eye. Your boat stays in the middle of the river, a comfortable distance away from the researchers.
The quiet is shattered
Suddenly, there’s a tremendous commotion at the researchers’ boat. Through violent splashing and the now bouncing spotlight, you see that one member of the research team at the bow of the boat has slid a capturing tool—nothing more than a wire noose on the end of a long pole—over the head of an angry black caiman.
The caiman thrashes about as if fighting for its life. It slams its massive head against the side of the boat. The boat’s steel-reinforced sides are doing their jobs. After a long, fierce struggle, the caiman is finally subdued, and dragged alongside the boat to a sandy clearing on the riverbank. Your boat captain heads for the riverbank, and you step off onto the soft sand.
The researchers slip a second, smaller noose around the caiman’s snout. Once secure, the animal’s snout is taped shut, and the noose removed. (Like alligators, caimans use very powerful muscles to close their mouths, but not to open them.) The caiman is flipped on its back, which essentially renders it powerless, and the researchers beckon you to approach.
The first thing the researches do is to check it the freshly captured caiman is one they’ve caught before. If so, they note the date of the tagging so they can measure the animal’s progress. If not, the caiman is tagged through a complex system of removing a few scales from its tail. This does not harm the animal.
If you’ve ever wondered what a black caiman feels like, this is your chance to find out. You can kneel down beside the caiman, and run your hands over its coarse tail and smooth belly. The researchers may even ask you to hold down the caiman’s tail while they measure its length. (Black caiman can reach up to 15 feet in length.) Next, the researchers determine the sex of the caiman. Because this can’t be done visually, the researchers reach into a small hole on the animal’s belly and determine which sex organs are inside.
Finally, the caiman is tied to a beam with a scale on it, and hoisted into the air by two researchers to determine its weight—usually between 150 and 200 pounds for adults.
With all the information carefully recorded, it’s time to release the caiman. The researchers flip the caiman back onto its belly, cut the tape holding its mouth closed, and with the noose still around its neck, lead the caiman down to the water. The researchers carefully loosen the noose, and gradually pull it off entirely.
The caiman, having been through quite an ordeal, is often exhausted and/or disoriented, and needs to be coaxed back into the water with shouts and claps from the researchers. Eventually, however, the caiman slides into the dark river and swims away. You can’t help but think about the caiman returning to his friends, saying, “Guys, you are not going to believe what just happened to me.