Why is this important?  Genetic diversity is like a population’s insurance policy against disease and environmental change; the more diverse a population, the better its chances of survival.  Until now, eDNA surveys could only tell scientists which species were present .  This study shows that we can also estimate population size and health without ever touching the animals.  The researchers are calling for new monitoring programmes to be rolled out so we can track dolphin populations and see how human activities like pollution and underwater noise are affecting them .

We think this non‑invasive approach is a game‑changer for dolphin conservation and offers hope that we can better protect these intelligent creatures.  Read the full article here: https://www.frontiersin.org/news/2026/05/19/frontiers-marine-science-edna-dolphins-california

Read full article: The Animal Fund

The New Zealand ichthyosaur was found on the Coverham Station farmstead in the Canterbury region, about 200km northeast of Christchurch.

Rocks from this region of the Clarence Valley date to the Cretaceous period (141–66 million years ago) when the area formed the bed of an ancient sea. The ichthyosaur fossil is 98 million years old.

Back then, New Zealand itself was further south and was part of the supercontinent Gondwana, joined with Australia, Antarctica and South America.

Marine reptiles from the “Age of Dinosaurs” have been found in New Zealand before. Among them is the oldest known marine reptile found in the southern hemisphere. But the new species provides a rare glimpse into ichthyosaurs of Eastern Gondwana. It is the first ichthyosaur found on New Zealand’s South Island.

The fossil is also the most completely preserved individual ichthyosaur found in New Zealand.

Full story: Cosmos

Campaigners and the zoo’s managers have been locked in disagreement about what should happen to the orca whales with the French government already blocking one proposal to rehome them.

Last month Marineland Antibes, located near Cannes in the French Riviera, said it would permanently shut on 5 January following new animal welfare laws.

The legislation, which bans the use of dolphins and whales in marine zoo shows, was passed in 2021 but comes into effect next year.

Marineland, which describes itself as the largest of its kind in Europe, currently keeps two killer whales – Wikie, 23, and her 11-year-old son Keijo.

Campaigners want Wikie and Keijo to be sent to a sanctuary instead of zoos in Japan and Tenerife

Managers say shows featuring killer whales and dolphins attract 90% of Marineland’s visitors – and that without it the business isn’t viable.

Several destinations for the whales have been proposed but there is disagreement on where they should go and what should happen to them.

Most experts agree that releasing the two whales, which are Icelandic orcas specifically, into the wild would not be suitable as both were born in captivity and would not have the skills to survive.

“It’s a bit like taking your dog out of the house and sending him into the woods to live freely as a wolf,” says Hanne Strager.

In 2023 the marine biologist published The Killer Whale Journals, which details her decades long interest in the ocean predator and how they behave.

“Those whales, that have spent their entire lives in captivity, their closest relationship is with humans. They are the ones who have provided them with food, care, activities and social relations.

“Killer whales are highly social animals, as social as we [humans] are, and they depend on social bonds. They have established those bonds with their trainers … They depend on humans and that is the only thing they know.”

Full story: BBC

“Really impressed by all the detail of a hypothetical dolphin culture and lots of great scientific information about the ocean and dolphins. It has several good messages weaved into the writing and a bit of drama, action, and even love. Every enjoyable. Perfect book to disappear into and get through a long airplane ride or two.”

Evolution understands this too well— and now, a recent study published in the Proceedings of the Royal Society B found that when a mammal becomes fully aquatic, it becomes nearly impossible to return to terrestrial landscapes.

Is evolution reversible?

Around 350 to 400 million years ago, the first fish ventured onto land, developing primitive limbs that enabled them to move about. Over time, their descendants evolved into the tetrapods we know today. 

While this transition from water to land occurred only once, the reverse transition from land to water has happened repeatedly, prompting researchers to question whether aquatic mammals could ever revert to a terrestrial lifestyle.

Belgian paleontologist Louis Dollo initially proposed that evolution was irreversible in the 19th century. Dollo’s law states that once a complex trait is lost in a lineage, it is unlikely to reappear in subsequent generations.

To investigate this idea in mammals, scientists analyzed over 5,600 mammal species, categorizing them into four groups: fully terrestrial, semi-aquatic with some land mobility, limited land locomotion, and fully aquatic species such as whales.

“One of the main points of our work was to include the entire gradient of adaptations from fully terrestrial to fully aquatic forms and to test if these adaptations were irreversible,” said lead study author Bruna Farina, a doctoral student at the University of Fribourg in Switzerland, in a Live Science article. 

The study revealed a threshold between semi-aquatic and fully aquatic species. Once this threshold is crossed, the adaptations to an aquatic lifestyle become irreversible. 

Transitioning to aquatic environments necessitated multiple changes, including increased body mass to retain heat in colder surroundings and a carnivorous diet to support their heightened metabolism. These adaptations could hinder competition against terrestrial organisms.

While shifting from fully terrestrial to semi-aquatic in incremental steps is possible, the researchers concluded that an irreversible threshold exists for particular aquatic adaptations. 

“We found that it’s possible to go from fully terrestrial to semiaquatic in [small steps], but there’s an irreversible threshold for some aquatic adaptations,” Farina said. 

Therefore, she explained that the chance of fully aquatic animals, like whales and dolphins, returning to the land is virtually zero. 

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Full story: Interesting Engineering

Since the attacks began in 2020, three boats have been sunk and more than 250 damaged by a group of orcas, with the animals appearing to deliberately target the vessels’ rudders.

Of the 35 killer whales in the region, 15 are reported to have been involved in the highly unusual interactions, which experts think began after White Gladis’ behaviour altered in a ‘defensive’ fashion after she suffered a ‘critical moment of agony’ involving a boat collision or illegal fishing entrapment – leading to other orcas damaging passing vessels in response.

A study published in June 2022 in the journal Marine Mammal Science has found that assaults by the orcas are directed mainly at sailing boats. There is a clear pattern of orcas striking the rudders, with spade rudders the most targeted and damaged type, and then losing interest once the boat has successfully stopped. 

Full story: Dive Magazine

The Russian President’s war efforts were rocked on Saturday when a section of the Kerch Bridge – which links Russia with Crimea – was blown to bits in a suspected Ukrainian attack. 

Speculation over the mode of attack has been feverish, with some suggesting a covert operation by a specialised team in the Ukrainian military and others raising the possibility of a long-range missile.

The Kerch bridge was guarded on all fronts with missile defence systems, fighter jets, warships, military divers and heavy artillery.

But one small detail spotted in the dramatic footage of the blast has brought the role of Russia’s military dolphins back into sharp focus.

In one CCTV clip, a small wave appeared to roll under the bridge just before the explosives were detonated, fuelling speculation about the possibility of Ukrainian special forces using a boat or water-based drone to launch the attack. 

This is exactly the type of attack that the navy dolphins have allegedly been trained to intercept, with reports that the mammals are patrolling the waters across the Azov and Black Sea ready to hunt down enemy frogmen.

While their deployment during the Ukraine conflict is unconfirmed, further speculation over the use of the mammals arose when satellite images showed two dolphin pens were moved to Russia’s Sevastopol harbour naval base – which sits on the southern tip of Crimea – in February of this year. 

Russia has a history of training dolphins for defence purposes including the clearance of underwater mines and the protection of military sites and ships from the threat of covert enemy divers. The Russian government first started exploring the military uses of marine mammals at the Sevastopol naval base during the Soviet era. 

The US and Russia developed the use of military dolphins during the Cold War, harnessing their echolocation capabilities to detect underwater objects such as mines.

More recently, satellite imagery captured in 2018 revealed that Russia was using dolphins at its naval base in Tartus, Syria during the Syrian civil conflict. The US is reported to have spent almost $30m maintaining its own battalion of military dolphins.

Full story: The Sun

Dolphins form decade-long social bonds, and cooperate among and between cliques, to help one another find mates and fight off competitors, new research has found – behaviour not previously confirmed among animals.

“These dolphins have long-term stable alliances, and they have intergroup alliances. Alliances of alliances of alliances, really,” said Dr Richard Connor, a behavioural ecologist at the University of Massachusetts Dartmouth and one of the lead authors of the paper. “But before our study, it had been thought that cooperative alliances between groups were unique to humans.”

The findings, published on Monday in the journal Proceedings of the National Academy of Sciences, appear to support the “social brain” hypothesis: that mammals’ brains evolved to be larger in size for animals that keep track of their social interactions and networks. Humans and dolphins are the two animals with the largest brains relative to body size. “It’s not a coincidence,” Connor said.

Connor’s team of researchers collected data between 2001 and 2006 by conducting intensive boat-based surveys in Shark Bay, Western Australia. The researchers tracked the dolphins by watching and listening to them, using their unique identifying whistles to tell them apart.

They observed 202 Indo-Pacific bottlenose dolphins (Tursiops aduncus), including during the peak mating season between September and November.

Back in the lab, they pored over data focusing on 121 of these adult male dolphins to observe patterns in their social networks. And for the next decade they continued to analyse the animals’ alliances.

Dolphins’ social structures are fluid and complex. The researchers found alliances among two or three male dolphins – like best friends. Then the groups expanded to up to 14 members. Together, they helped each other find females to herd and mate with, and they help steal females from other dolphins as well as defend against any “theft” attempts from rivals.

“What happens as a male, you might be in a trio, herding a female. And if someone comes to take that female, the other males in your team and your second-order alliance come in and help you,” said Dr Stephanie King, professor in animal behaviour at Bristol University and one of the authors of the study. “These males have a very, very clear idea of who is in their team.”

These teams can last for decades and are formed when the dolphins are still young, although they do not tend to reap the rewards of paternity until their mid-teens, King said. “It’s a significant investment that starts when they’re very young – and these relationships can last their entire lives.”

Sometimes, especially when dolphin groups feel there is a risk to themselves, two second-order alliances will also come together to form a larger team. As a result, among the dolphins observed by the scientists, every male was directly connected to between 22 and 50 other dolphins. 

The researchers’ observations show that in these groups, the tighter the clique – and the stronger the bonds between the dolphins – the more success they have attracting females.

It’s their cooperative relationships, rather than alliance size, which gives males more breeding success, said King.

It is already widely known that dolphins are highly social and cooperative, as well as being remarkably good at adapting to and teaching behaviour specific to their environment, said Stephanie Venn-Watson, former director of Translational Medicine and Research at the National Marine Mammal Foundation in San Diego, California, who was not involved in the study.

Full story: The Guardian