A whale carries its ecosystem on its skin
In the cold waters of Argentina's San Matías Gulf, a photographer's careful eye revealed what science had not yet recorded: reddish, barnacle-like organisms clustered on the callosities of a southern right whale, never before documented on this species. The discovery, confirmed by CONICET researchers, reminds us that even the most studied creatures carry secrets — that the surface of a living being is itself an ecosystem, and that the ocean's complexity continues to exceed our maps of it.
- A routine whale survey off Patagonia's coast became extraordinary when photographer Maximiliano Cartés spotted unfamiliar reddish structures clustered on a southern right whale's callosities — structures no one had recorded before.
- The find sent an immediate ripple through the marine biology community, as the organisms appeared to resemble barnacles yet had never been documented on this species, raising urgent questions about what else may have gone unnoticed.
- Dr. Magdalena Arias of CONICET confirmed the organisms' novelty and noted a critical clue: similar structures had been observed on humpback whales in the same gulf, suggesting cross-species ecological patterns worth investigating.
- Researchers now face an open frontier — which species are colonizing whale skin, how are they interacting, and what does this mean for understanding the living ecosystems that migrate with these animals each season?
When photographer Maximiliano Cartés set out on a survey of the San Matías Gulf during the early southern right whale season, he wasn't expecting to change anything. But on the head of one whale, clustered directly over the callosities — those distinctive whitish, bumpy patches unique to the species — he saw something that stopped him: reddish structures, grouped and unfamiliar, resembling barnacles but unlike anything previously recorded on southern right whales.
Cartés shared the images publicly, describing the organisms with precision, and the photographs quickly reached Dr. Magdalena Arias, a researcher at CIMAS and part of CONICET. She confirmed what the images suggested — these organisms had never been documented on this species. The callosities of southern right whales are already known to host communities of cyamids, cirripedes, and other small hitchhikers, but this was something else entirely.
Arias noted that similar organisms had been found on humpback whales in the same gulf, a detail that deepened the mystery and pointed toward broader questions about biological interactions on whale skin. The discovery, made along the coast near Las Grutas in Río Negro province, was the first confirmed record of this organism association in the San Matías Gulf — and possibly anywhere.
What the finding quietly insists upon is this: a whale is not just an animal moving through water. It is a living platform carrying its own ecosystem, and the relationships unfolding on its skin are part of the ocean's larger architecture. This single photograph has opened a door that marine science is only beginning to walk through.
A photographer working the waters off Argentina's Patagonia coast made an observation that would ripple through marine biology. Maximiliano Cartés was out on a routine survey in the San Matías Gulf during the early weeks of the southern right whale season when he noticed something on the head of one whale that stopped him cold: reddish structures clustered directly on the animal's callosities, those distinctive whitish, bumpy patches that mark the species. He captured the images. What seemed like another day's documentation became something else entirely.
Cartés shared his find on social media with a clarity that suggested he understood its weight. He described seeing "several reddish structures grouped over the callosities"—organisms that resembled barnacles, clustered in a pattern never before recorded on southern right whales, possibly never recorded anywhere. The callosities themselves are home to a known menagerie: tiny crustaceans called cyamids, or whale lice, along with other hitchhikers like cirripedes and what researchers call dog teeth. But this was different. This was new.
Dr. Magdalena Arias, a researcher at CIMAS (the Applied Research and Technology Transfer Center for Marine Resources "Almirante Storni") and part of Argentina's National Council of Scientific and Technical Research (CONICET), examined the photographs. She confirmed what Cartés had intuited: the reddish organisms bore a striking resemblance to barnacles, and they had never been documented on southern right whales before. The discovery opened a door. Arias noted that similar organisms had been found on humpback whales in the same gulf, which raised a question that would occupy researchers going forward: what biological interactions were happening on the skin of these whales, and which species were sharing that habitat?
The work was conducted along the coast near Las Grutas in Río Negro province, in the heart of Argentine Patagonia. Cartés acknowledged the collaboration that made the documentation possible, thanking Agustín Barschi and biologists from Chubut province for their immediate engagement with the finding. What had begun as a single whale, a single observation, became a marker—the first confirmed record of this organism association in the San Matías Gulf, and possibly the first anywhere.
The implications sit quietly beneath the surface. A whale carries its ecosystem on its skin. Every organism attached to it, every interaction between species on that living platform, tells something about the ocean's architecture. This discovery suggests that architecture is more complex than previously understood. The southern right whales that migrate to Argentine waters each year are not simply moving through an environment; they are moving through a web of relationships that science is only beginning to map. What other organisms are waiting to be seen? What other questions does a single photograph raise?
Notable Quotes
This type of associated organism had never been recorded previously on southern right whales— Dr. Magdalena Arias, CONICET researcher
What seemed like another record turned out to be a milestone for science— Maximiliano Cartés, photographer
The Hearth Conversation Another angle on the story
What made this discovery different from the thousands of whale observations that happen every year?
Because no one had ever seen this particular organism on this particular whale species before. It's not that whales are new or that we haven't studied them—it's that the ocean keeps showing us we don't know what we think we know.
So the photographer was just lucky?
Luck and attention. Cartés was looking. He saw something that didn't fit the pattern he expected, and instead of moving on, he documented it and shared it with scientists who could verify it.
What does it mean that similar organisms show up on humpback whales but not on southern right whales—until now?
It suggests the whales might be encountering different ecological conditions, or that these organisms are spreading, or that we simply haven't been looking carefully enough. It opens questions instead of closing them.
Does this change how we understand whale health?
Not immediately. But understanding what lives on a whale's skin is part of understanding the whale itself. If new organisms are colonizing these animals, that's information about the ocean's changing conditions.
What happens next?
More observation. More photographs. Scientists will be watching for this organism on other whales, in other seasons, trying to understand whether this is rare or whether it's been there all along and we simply hadn't noticed.