1. World Wildlife Magazine
  2. Spring 2018
In-Depth

Current status

WWF tags river dolphins in Bolivia, Brazil, and Colombia to learn more about the species

PUERTO NARIÑO, COLOMBIA  ::  3 NOVEMBER 2017

According to WWF’s Living Planet Report, the average abundance of freshwater species populations declined by 81% between 1970 and 2012. This startling statistic underscores the desperate situation faced by freshwater species—including the charismatic and iconic river dolphin. In response, WWF offices in Bolivia, Brazil, and Colombia coordinated a tri-national effort to tag and study river dolphins, applying satellite GPS technology to the task for the first time. The project is part of a broader scientific attempt to understand river dolphin health and migratory patterns, which is an early step in creating a regional approach to collecting and sharing data about river dolphins across Bolivia, Brazil, Colombia, Ecuador, Peru, and Venezuela. These findings will inform plans to secure the landscapes and rivers these dolphins need to survive.

For five days, a research team explored the waters in and around the Tarapoto lakes, near the Peruvian border, hoping to add data about Colombia’s river dolphins to the project. Unexpectedly high waters gave the dolphins a wider roaming range than usual, and the crew captured only one dolphin during the expedition. Here’s what it took to get the job done.

 

RINSE AND REPEAT

A local fisherman, guided by WWF and scientists from the Omacha Foundation, casts a net to capture a dolphin. Many casts were unsuccessful and the team had to bring the net back to the boat multiple times, a process that could take up to 30 minutes.

HANDLE WITH CARE

Four adult dolphins are surrounded by nets in an attempted capture. When one is finally enclosed in a net, team members enter the water, splashing to create distractions and prevent the animal from escaping.

PROCEED WITH CAUTION

The next step is getting the dolphin into the boat. The powerful animals can weigh more than 300 pounds, so the procedure requires both careful strategy and a good deal of strength. Once they have a dolphin on board, the team transfers it from the boat to a stretcher on which it will be transported to waiting veterinarians.

CATCH AND RELEASE

The veterinarians install a GPS tag on the dorsal fin of the dolphin by means of a quick and clean procedure that takes about 15 minutes. Meanwhile, other team members take weight and length measurements, as well as small skin samples to analyze for mercury levels and genetic information.

CONNECT THE DOTS

After the tag has been installed, the team gently lowers the dolphin back into the river. Over the course of expeditions in Brazil, Bolivia, and Colombia, 11 dolphins have been tagged and released. Data from the tags will be collected via satellite, giving researchers a more complete picture than ever before of the movements of Amazon river dolphins.

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World Wildlife magazine provides an inspiring, in-depth look at the connections between animals, people and our planet. Published quarterly by WWF, the magazine helps make you a part of our efforts to solve some of the most pressing issues facing the natural world.

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