Commotion in the ocean: Smart buoys to protect whales from noise

As noise pollution grows in the depths of the world’s oceans, whale populations, which rely heavily on sound for orientation and communication, are suffering. The Chilean government is deploying a network of hi-tech buoys to help protect the giant marine mammals and the wider ecosystem. — dpa

CASTRO, Chile: Ship engines, construction work on wind farms, military sonar: This underwater cacophony is dangerous for many sea creatures and especially for whales, which use sounds to orient themselves, find food and communicate with other animals.

If it gets too loud in their habitat the marine mammals can lose their bearings. Off the coast of Chile, the whales are now to be protected from noise pollution with a system of buoys that will also warn approaching vessels so as to avert collisions.

“The noise creates communication problems between whales, meaning they can't find each other to breed, and it also hinders foraging, which has a direct impact on population growth,” says Yacqueline Montecinos, marine biodiversity conservation manager for the World Wildlife Fund (WWF)in Chile.

According to German environmental protection organiation Nabu, the background exposure to underwater noise in the oceans has doubled or even tripled in the last few decades.

So-called masking effects – when the whale’s detection of sounds of interest is degraded by other sounds in the vicinity – occur at lower volume levels or at greater distances from the noise source. At higher volumes, the animals can also injure their ear canals or, in extreme cases, even die.

Because of increasing shipping traffic, collisions between ships and whales occur again and again. The International Whaling Commission recorded nearly 1,500 collisions between 2007 and 2016. However, the actual number is likely to be much higher as many collisions go unnoticed or unreported.

With their Blue Boat Initiative, the Chilean Environment Ministry and the Meri Foundation will use hi-tech buoys to better protect the whales from collisions with ships and exposure to underwater noise.

Launched in mid-October, the first buoy was called “Suyai”, which means “hope” in the language of the indigenous Mapuche. If its acoustic sensors locate marine mammals in the area it sends a real-time signal to the Chilean Navy, which in turn warns nearby ships. The captains should then slow down or change course.

Developed at the University of Barcelona, the buoys can also measure temperature, pH values, salinity and the saturation of the water with nutrients and oxygen.

“In the next few months we will place five more buoys in the Gulf of Corcovado,” between the southern island of Chiloé and mainland Chile, says the director of the Meri Foundation, Sonia Español-Jiménez. “In the long term we want to install a whole system of buoys along the entire American Pacific coast and up to Canada.”

Nine different species of whale live in the Gulf of Corcovado. The region is particularly important for blue whales: 10% of the global population of the world’s largest animals come to the Gulf to look for food and raise their young.

Meanwhile, the more than 50-kilometre-wide waterway is extremely busy, mainly with sea traffic from the numerous salmon farms in the region across the Gulf.

The researchers hope that the data will provide further insights into the changes in the whales’ habitat. At the same time, the protection of marine mammals also represents a contribution to the fight against climate change.

“Whales are considered the engineers of the oceans, absorbing, distributing and releasing nutrients, thereby contributing to the formation of phytoplankton,” says Español-Jiménez. “These algae break down CO2 via photosynthesis and produce a large part of the oxygen in the atmosphere.”

What’s more, whales themselves directly remove large amounts of climate-damaging CO2 from circulation by absorbing it. When they die, they sink to the ocean floor and all the carbon stored in their bodies is deposited in the deep sea, where it remains for centuries.

“Whales are of great value to the planet. It is estimated that each specimen accumulates around 33 tons of CO2. That’s the same capacity as 1,000 trees,” says WWF expert Montecinos. – dpa