Beaked Whales Plunge Nearly a Kilometer Deep in Routine Hunts

Some of the ocean’s most elusive mammals are also among its most extreme athletes. New acoustic research shows that beaked whales routinely dive nearly a kilometer beneath the surface — and sometimes deeper — as part of their normal hunting behavior in the dark waters of the Gulf of Mexico.

Using underwater listening devices instead of visual tracking or satellite tagging, scientists reconstructed the three-dimensional movements of several beaked whale species and documented how far down they travel in search of prey. The findings provide one of the clearest pictures yet of how these rarely seen whales use the deep sea.

The research was published Feb. 4, 2026, in the journal PLOS One under the title Beaked whale dive behavior and acoustic detection range off Louisiana using three-dimensional acoustic tracking. The study relied on fixed hydrophone arrays positioned roughly 1,100 meters below the surface off the coast of Louisiana.

“Beaked whales are some of the most challenging marine mammals to study because they spend so little time at the surface,” said marine scientist Dr. Julie Oswald, one of the researchers involved in the study. “By using passive acoustic monitoring, we’re able to observe their diving behavior in a way that doesn’t disturb them and doesn’t require attaching tags.”

Diving Into the Deep

Beaked whales are deep-diving toothed whales known for their long, narrow snouts and secretive behavior. In the Gulf of Mexico, the study identified three primary species: the goose-beaked whale (Ziphius cavirostris), Gervais’ beaked whale (Mesoplodon europaeus) and Blainville’s beaked whale (Mesoplodon densirostris).

The acoustic data revealed that these whales consistently descend to depths that would crush most air-breathing animals. Goose-beaked whales were recorded making foraging dives ranging from approximately 888 to 1,208 meters, with average clicking depths around 983 meters. In several cases, the animals appeared to approach the seafloor itself, which in the study area lies at roughly 1,100 meters.

Gervais’ beaked whales typically dove to around 865 meters, with maximum recorded depths near 910 meters. Blainville’s beaked whales showed average dive depths of about 795 meters and maximum depths around 861 meters.

While the maximum dive depths were partly constrained by the depth of the seabed in the study area, the findings confirm that routine foraging dives take these animals into an environment of extreme pressure, near-freezing temperatures and almost complete darkness. At 1,000 meters, sunlight disappears entirely and pressure exceeds 100 times that at the surface.

What makes the findings notable is not simply how deep the whales can go, but how often they do so. These are not rare, record-setting plunges. They are routine feeding dives.

Listening Instead of Tagging

Rather than attaching electronic tags to the whales, researchers used passive acoustic monitoring. Beaked whales emit highly distinctive echolocation clicks while hunting. By placing multiple hydrophones on the ocean floor and measuring differences in the arrival times of these clicks, scientists reconstructed the whales’ dive paths in three dimensions.

“Each click tells us something about where the whale is and what it’s doing,” Oswald said. “When they begin clicking, it usually signals the start of the foraging phase at depth.”

The study found that whales typically begin clicking after descending several hundred meters. The clicking phase continues during active hunting in deep water and stops as the whale ascends toward the surface. The ascent phase is often more direct and faster than the descent, reflecting a consistent behavioral rhythm. Descend quietly, hunt at depth using echolocation, then return to breathe.

A single foraging dive can last more than an hour. Between deep dives, whales may perform shorter, shallower recovery dives before descending again. The regularity of this pattern underscores how central deep diving is to their survival strategy.

The acoustic method also allowed researchers to estimate detection ranges of whale clicks and better understand how sound travels in deep offshore waters. That information is critical for population monitoring and conservation planning, particularly in areas where industrial activity overlaps with whale habitat.

Built for Extreme Pressure

Beaked whales are widely regarded as some of the deepest-diving mammals on Earth. Previous studies of related populations have documented dives exceeding 2,900 meters in other regions. Although the Gulf of Mexico study did not record dives that deep — likely because the seafloor limited descent — the findings reinforce the species’ extraordinary physiological capacity.

To survive such dives, beaked whales rely on specialized adaptations. Their lungs collapse at depth, reducing nitrogen absorption and lowering the risk of decompression sickness. They possess high concentrations of myoglobin in their muscles, allowing them to store oxygen efficiently. Their heart rate slows dramatically during dives, conserving both oxygen and energy.

“Every deep dive represents a balance between oxygen use, prey availability and safe ascent,” Oswald said. “These whales are finely tuned to a part of the ocean that humans rarely experience.”

Understanding that balance is increasingly important as human activities extend farther offshore. Naval sonar, oil and gas exploration and commercial shipping generate noise that can penetrate into the depths where beaked whales forage. The species has previously been linked to strandings associated with intense sonar exposure, making knowledge of their dive behavior essential for mitigation strategies.

The study also suggested subtle differences among species. Goose-beaked whales tended to dive deeper than the two Mesoplodon species observed. That variation may reflect differences in prey preference or ecological niche, with some species targeting organisms closer to the seabed while others exploit mid-water prey.

How They Compare With Manta Rays

The remarkable diving abilities of beaked whales stand out even more when compared with other large marine animals. In October 2025, an article published on Lingkar Bumi titled Manta Ray Dives as Deep as Three Times the Height of the Eiffel Tower reported that oceanic manta rays had been recorded diving to approximately 1,250 meters.

The article described how researchers documented rare deep dives by manta rays — equivalent to stacking the Eiffel Tower three times from base to tip. For a large fish best known as a surface-feeding filter feeder, such a descent is striking.

However, the context differs. According to the report, deep manta dives appear to be occasional rather than routine and may be related to navigation, environmental conditions or exploratory behavior rather than sustained deep foraging.

Beaked whales, by contrast, dive to extreme depths repeatedly as part of their daily feeding ecology. They are air-breathing mammals that must carefully manage oxygen stores and endure immense pressure before returning to the surface. Their use of echolocation in complete darkness further distinguishes them from manta rays, which rely on filter feeding and do not emit high-frequency biosonar clicks.

Both species demonstrate that the deep ocean is far from empty. Yet in terms of frequency, duration and physiological specialization, beaked whales remain among the most consistent and extreme deep divers in the marine world.

Nearly a kilometer beneath the waves is not an occasional frontier for these whales. It is their hunting ground — a realm of crushing pressure and darkness that they navigate with precision, repeatedly and routinely, in one of the ocean’s most extraordinary feats of endurance. (Wage Erlangga)