Baleen Whales Found To Be 'Singing' Under Water, Study Says

Experts said that baleen whales are capable of singing under water, with studies indicating that noise pollution from shipping activity can make some changes towards a marine mammal's ability to communicate.

Vocalizations To Mediate Behaviors

A Nature study indicated that when the ancient ancestors of whales returned to the ocean from land, they were observed to have developed major adaptations to make vocal communication possible underwater.

Baleen whales or mysticetes use vocalizations to mediate their complex social and reproductive behaviors in vast, opaque marine environments. Scientists found out that adapting to an obligate aquatic lifestyle demanded fundamental physiological changes to efficiently produce sound, including laryngeal specializations.

Whereas toothed whales (odontocetes) evolved a nasal vocal organ5, mysticetes have been thought to use the larynx when it comes to sound production.

However, research suggested that there has been no direct demonstration that the mysticete larynx can phonate, or if it does, how it produces the great diversity of mysticete sounds.

In the study, experts combined experiments on the excised larynx of three mysticete species with detailed anatomy and computational models to show that mysticetes evolved unique laryngeal structures for sound production.

These structures allow some of the largest animals that ever lived to efficiently produce frequency-modulated, low frequency calls. Furthermore, scientists showed that this phonation mechanism is likely to be ancestral to all mysticetes and shares its fundamental physical basis with most terrestrial mammals, including humans, birds, and their closest relatives, odontocetes.

However, it was pointed out that these laryngeal structures set insurmountable physiological limits to the frequency range and depth of their vocalizations, preventing them from escaping anthropogenic vessel noise and communicating at great depths.

This then greatly reduced their active communication range.

The data found in the study conclusively demonstrated that the mysticete larynx has retained its key role as a vocal organ, which, despite numerous anatomical specializations, functions by the same myoelastic-aerodynamic principles as the larynx in humans and most other terrestrial mammals.

Vessel, Shipping Pollution

Meanwhile, vessel noise pollution and shipping intensity is seen to result in a real threat to large whales.

Research has shown that constant shipping noise can dominate the ocean soundscape and cause stress levels to rise in some species, especially the critically endangered North Atlantic right whale.

Due to the deaths of five North Atlantic right whales since December, there have been renewed calls for federal shipping regulations.

A coalition of environmental groups filed a federal lawsuit to finalize shipping speed rules proposed in 2022 that would require mariners off the East Coast to slow down in order to reduce the risk against endangered whales swimming in the area.

So far, experts said that ongoing research efforts, coupled with working directly with local harbor safety committees, the maritime industry and government agencies, are necessary to ensure the protection of baleen whales.