How Smelly Plankton Could Help Save Endangered Right Whales

Science and technology have always thrived on unexpected connections—from using artificial intelligence to track animal migrations to deploying drones for coral reef monitoring. But what if saving one of the world’s most endangered whales could come down to something as simple as the scent of plankton in the air?

For North Atlantic right whales, every breakthrough matters. With fewer than 350 individuals left, this species is on the brink of extinction. One of the biggest threats they face? Collisions with ships. 

The whales most at risk are females with calves—the very individuals most essential for species recovery. These mother-calf pairs spend more time at the surface, where they are most vulnerable to ship strikes. Research by Susan Parks and colleagues has shown that mother-calf pairs “whisper” to each other using low-amplitude calls, likely to avoid predators (Parks et al., 2019). But their quiet communication also means they evade detection by the very systems meant to protect them—making it critical to find new ways to anticipate their arrival in highly traveled waters.

That’s where an unexpected tool comes in: dimethyl sulfide (DMS), a gas released into the ocean and atmosphere when tiny plankton get eaten.

The Science of Plankton Popping and Whale Finding

Right whales are plankton specialists, relying almost entirely on tiny, shrimp-like zooplankton for food. These zooplankton, in turn, feed on phytoplankton, the microscopic marine plants that form the base of the ocean food web.

Phytoplankton don’t just float passively—they contain DMS, a gas that helps them regulate their internal pressure. When zooplankton consume them, it’s like popping a balloon—DMS is suddenly released into the water and air.

Since right whales seek out dense swarms of zooplankton, areas with high DMS levels may serve as a natural roadmap to the best feeding grounds. My colleagues and I are exploring whether tracking DMS levels in the atmosphere could provide an early-warning system for whale presence—before the whales even arrive.

If right whales are using DMS as a natural cue to find their food, then scientists might be able to use the same signal to help prevent deadly ship strikes.

A Whale’s Sense of Smell: Following the Stereo Scent Trail

Many marine species—from seabirds to sharks—are known to track chemical signals in the water to locate prey. But recent studies suggest that baleen whales, including right whales, may have the ability to detect airborne DMS while surfacing to breathe.

One leading theory, the stereo smell hypothesis, suggests that some whales could have bilateral olfaction—meaning they might be able to “smell in stereo,” detecting slight differences in scent between their two nostrils. This ability would allow them to follow DMS gradients in the air, helping them hone in on the richest plankton blooms.

If this is the case, then right whales are essentially sniffing out their next meal, just as wolves follow a scent trail on land.

This idea isn’t new—19th-century Yankee whalers often reported smelling whales before seeing them, describing a fishy odor. Today, instead of using that knowledge to hunt whales, scientists are flipping the script—using ocean chemistry to protect them.

If tracking DMS concentrations can help predict where right whales will feed, it could provide a dynamic, science-driven approach to whale conservation.

Instead of relying solely on seasonal speed restrictions and static shipping lane adjustments, real-time DMS monitoring could allow for adaptive management—warning mariners only when conditions suggest whales are likely to be present. This approach could:

Improve the accuracy of slow-down zones, reducing unnecessary disruptions while keeping whales safe.

Give scientists new tools to track right whales, especially in low-visibility conditions where traditional surveys fall short.

Help inform conservation policies that adapt to climate-driven changes, as shifting ocean temperatures impact where and when whales find their food.

Where Science Meets Innovation

At first glance, the idea of tracking whales with plankton gas sounds almost too simple. But history has shown that some of the biggest breakthroughs come from unexpected places—whether it’s using satellites to spot illegal fishing vessels or training AI to recognize bird songs.

If the scent of popped plankton can help right whales find food, maybe it can also help humans find better ways to protect them.

Science is at its best when it challenges us to see connections we hadn’t noticed before. Right now, those connections might just be floating invisibly on the ocean breeze.

Let’s Keep Exploring

If you’re interested in the intersection of science, technology, and conservation, follow along as I continue researching innovative solutions for marine life protection. From AI-assisted wildlife monitoring to chemical cues in the ocean, the next big breakthrough might be hiding in plain sight—or, in this case, floating just above the water.