Current research & recent discoveries

Cetacean science is going through a period of unprecedented activity. Genetics, artificial intelligence applied to bioacoustics, satellite telemetry, non-invasive methods using drones and environmental DNA: the tools of research are multiplying and revealing what was still unknown ten years ago. This page lists the major projects under way and summarises the notable discoveries of recent years.

The major projects under way

Project CETI: decoding the language of sperm whales

Launched in 2020, the Cetacean Translation Initiative (CETI) is probably the most ambitious bioacoustics project in history. Run by an international team off Dominica (Caribbean), it aims to record, analyse and, perhaps, translate codas, the rhythmic sequences of clicks that sperm whales exchange.

The first results are remarkable. A 2024 paper in Nature Communications (Sharma et al.) showed that codas have a far richer combinatorial structure than was thought, with systematic variations of tempo and rhythm that resemble modulable phonemes. The “vocabulary” identified would be much broader than the ~25 coda types known until then. CETI uses, among other things, acoustic tags carried by sperm whales, networked fixed hydrophones and transformer-type neural networks to pick out structural patterns.

The mystery of the 52 Hz whale

First detected in 1989 by William Watkins (Woods Hole Oceanographic Institution), this “loneliest whale in the world” continues to intrigue. Research is continuing thanks to the United States Navy’s SOSUS archives and to NOAA’s new hydrophone arrays. A 2020 study suggested that several animals could in fact share this atypical frequency, calling into question the romantic image of a single isolated individual. The “Loneliest Whale Project” expedition led in 2015 by Joshua Zeman picked up several sequences but without sighting the animal. No genetic specimen. The mystery remains. See our dedicated page.

Environmental DNA (eDNA)

A methodological revolution of the past five years: it is now possible to detect the presence of a cetacean simply by analysing the water it has passed through. Every cubic metre of ocean contains DNA fragments from the organisms that have been there. Laboratories such as that of Mehrdad Hajibabaei (University of Guelph, Canada) apply this technique to the monitoring of rare populations: the vaquita, the presumed extinct baiji, the remnant populations of Mediterranean sperm whales. A 2023 study made it possible to map the presence of the large rorquals in the western Mediterranean from water samples collected by civilian boats, without a single animal being sighted.

Drones and aerial photogrammetry

Light drones have transformed the study of cetaceans. They make it possible to observe behaviour without disturbance, to measure the size and body condition of individuals precisely (photogrammetry), and to collect biological samples (SnotBot: a drone that passes over a whale’s blow to collect the microdroplets). Teams such as that of Fredrik Christiansen in Denmark use this approach to follow the nutritional condition of southern humpback whales, which is proving a sensitive indicator of environmental upheaval in the Antarctic.

Notable recent discoveries

2024, a new killer whale taxonomy

Phil Morin and his colleagues at NOAA published in 2024, in Royal Society Open Science, a proposal for a major taxonomic split: the resident killer whales and the Bigg’s killer whales (transients) of the North-East Pacific would be two distinct species, to be renamed Orcinus ater and O. rectipinnus respectively. This decision, currently under review by the Society for Marine Mammalogy, would transform the conservation status of several populations. See our page on killer whales.

2023, the longevity of the bowhead whale accounted for

A study published in Nature identified features of the DNA repair system in the bowhead whale that could explain its exceptional longevity (more than 200 years documented). The cells of this species repair genetic damage more efficiently than those of other mammals, which reduces the accumulation of cancer-causing mutations and accounts for the low cancer rate in these animals despite their size. These results are of active interest to biomedical research on human ageing.

2022, the vaquita can still be saved

Jacqueline Robinson and her team showed in Science that, contrary to fears, the remnant vaquita population does not carry a load of deleterious mutations that would doom it. If mortality in nets stops immediately, the species could in theory recover from about ten individuals. The window is narrow, but it exists. See our dedicated page.

2022, blue whales filter 10 million microplastic particles a day

Shirel Kahane-Rapport and her colleagues (Stanford University) published in Nature Communications the first precise quantification of microplastic ingestion in the large baleen whales. The figures are staggering. See our page on microplastics.

2020, the breath-hold record of Cuvier’s beaked whale

A team led by Nicola Quick documented a breath-hold of 222 minutes in a Cuvier’s beaked whale off Cape Hatteras (North Carolina), that is 3 hours and 42 minutes without breathing. This extraordinary record far exceeds the previous one (137 minutes) and establishes Cuvier’s beaked whale once and for all as the deepest-diving mammal. Published in the Journal of Experimental Biology. See our records page.

The major scientific conferences

Several international meetings structure the researchers’ year.

• Society for Marine Mammalogy Biennial Conference: the great international gathering on marine mammals, held every two years in a different city (Palm Beach 2022, Perth 2024). More than 2,000 researchers.
• European Cetacean Society (ECS) Annual Conference: for European researchers. An annual conference held each spring in a different country.
• International Whaling Commission: the Scientific Committee meets annually, and the Commission every two years. It is the body that issues advice on whaling quotas and conservation status worldwide.
• ACCOBAMS Meeting of Parties: for the conservation of cetaceans in the Black Sea, the Mediterranean and the contiguous Atlantic area.

The reference scientific journals

To follow the research, several specialist journals publish regularly on cetaceans:

• Marine Mammal Science: the reference journal of the Society for Marine Mammalogy;
• Journal of Cetacean Research and Management: published by the IWC;
• Aquatic Mammals: short papers for a scientifically minded readership;
• Endangered Species Research: for conservation issues;
• Marine Pollution Bulletin: for questions of pollution, microplastics and contaminants.

The major general journals (Nature, Science, PNAS, Current Biology, Proceedings of the Royal Society B) also regularly publish the most notable discoveries, such as those cited on this page.

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Further reading