Drones Investigate the Amazon’s Dolphin Mystery

We already know that drones are ideal tools for data gathering in remote areas, relatively easy to operate and inexpensive to deploy compared to conventional methods. Unsurprinsgly, these factors have made the technology appealing to scientific researchers.

We’ve covered a few uses of drones in the world of conservation before, most memorably with Ocean Alliance. Now a new application has come to light on the Amazon river.

A team from WWF Brazil is working alongside researchers from Mamirauá Institute, based in the remote Amazonian town of Tefé. The aim: to collect as much aerial data as possible about the health and size of the local dolphin population.
To do this, they are turning to drones. Aerial footage of various stretches of the river is making the mammoth task of estimating the dolphin population significantly easier.

And that’s important, because two species of Amazon river dolphin are categorised as ‘data deficient’ by the International Union for Conservation of Nature. This means that nobody is sure how many dolphins live in the basin.

A few studies have suggested that certain dolphin species are declining, but without having a better idea of the figures, governments won’t be willing to make any changes.

The joint team from Mamirauá Institute and WWF Brazil are using drones to fill that data void. “We need to base everything – all the decisions and everything we push – on hard data and hard science,” Miriam Marmontel, a scientist at the Mamirauá Institute, told The Guardian.

She believes there are at least 10,000 botos – one species of native river dolphin – out there, but the real number could be as high as 100,000.

“This data builds slowly. It’s scary because there’s a lot of work going into it and you can’t really say anything. We need to focus on what’s really critical to help us get to a real status that can influence policy. We need numbers, we need information on mortality and reproduction. Those are crucial.”

There are plenty of threats to the local dolphin population that could explain the anecdotal reports of a reduction in numbers. These include the threat of fisherman’s nets, the killing of dolphins to provide bait for catching piracatinga and mercury contamination from gold mining.

And then there’s the Brazilian government’s plan to build dams throughout the Amazon basin. According to an article in Nature, 140 dams have either been built or are under construction. There are plans for 428 more.

It goes without saying that these would be impossible to pass for dolphins. The threat is that isolating communities will lower genetic diversity over time.

If researchers, empowered by drones, can officially label these dolphin species as “vulnerable” or “endangered”, people, wildlife agencies and governments may start to take notice.

So far the research team has more than 70 footage samples from different locations on the river. This aerial video is slowly giving them a clearer idea of dolphin numbers in the Amazon basin. Spotting them from a boat can be a challenge, but having the ability to watch and rewatch high-quality video – on top of the benefits of an aerial perspective – has turned out to be cheaper, more efficient and more precise.

Even with more drone flights, the vastness of the Amazon means the researchers’ drone dolphin database will only count for a tiny proportion of what’s out there. The big question is whether or not the IUCN considers what has been gathered enough to warrant upgrade the status of the Amazon dolphins.