Read all stories in the Science of the Seas series here.January 6, 2026 The “blue buttons” strewn on the beach along the tide-line were beautiful. An array of intricately engraved disks – large and small –decorated the beach, each with its translucent filaments billowed out like a skirt around a coin-shaped organelle. Seeing one or a few washed ashore is not unusual. As the fisher elder from Urur Kuppam, Palayam, explains, “It is the sign of a strong olini – a landward moving current.” But what we were witnessing near the Adyar estuary, and what our friend Nambirajan had documented in Palavakkam beach this morning signal a different phenomenon, Palayam suggests tentatively. A Wiki search for blue buttons will take you to an entry titled Porpita porpita: “It was first identified by Carl Linnaeus in 1758, under the basionym Medusa porpita” (emphasis added). Though often mistaken for jellyfish, Porpita porpita are floating colonies of organisms bound to a disc-shaped float that functions as a shared body. Blue buttons may have been identified and named within a European scientific system of classification for the first time in 18th century, but fishers and mariners have encountered, named and feared these cute buttons for millennia. “We call it ‘netti’,” Palayam anna explains. “If you touch the bubbles attached to threads that hang beneath, you will experience a sharp stinging sensation. It’s not life threatening like the Moolaan, but the sting can leave you hurting for half an hour.”“We regularly see them in the deep sea, carpets of them floating with the current. Small fish take shelter in the shade beneath them,” he adds. “I remember one instance quite well when I was a young apprentice on my uncle, Sivasundaram’s boat. I was drawing in the anchor rope when he called out sharply: ‘Dei! Here, hand over the rope to me. Watch me draw it in. You have to do it without touching those bubbles’.”When a shoal of netti floats by, the bubble-like nodules on their tentacles latch on to the rope surface. Only a trained eye will discern the threat posed by the innocuous droplets, and only a trained hand will avoid the painful sting that can make a grown man hop in pain.Palayam maintains a daily diary of observations of routine and extraordinary marine phenomena. The netti washed ashore today qualified as a noteworthy incident by his metrics, earning a full page’s worth of notes in his diary. Here’s how he explained it to me over phone:“It is not uncommon for netti to wash ashore with a strong tide when an Olini (an easterly landward current) is in force. Netti can’t swim. They move with the tide and current. With a strong Olini, netti from the deep sea are washed ashore along with the flotsam. This must have come ashore last night. I was out observing the sea at 9.30 pm last night. The tide was nearly full. This morning, just between the river mouth and the point east of Theosophical Society’s back gate, the beach was carpeted with netti. This was unusual for two reasons. We have always encountered netti on the beach. But only in small numbers – a handful strewn around the beach. In 2019, we witnessed a mass beaching in March. In 2022, I have noted encountering them on the beach, but that was not an incident of mass beaching. Today, we have witnessed a mass beaching. Even Nambi sent us a photo of a mass stranding in Palavakkam beach. “Yet, this year’s event is different from the 2019 one. In 2019, we saw even-sized nettis spread along the beach; this year’s beached nettis include thousands of tiny, small and large-sized disks littered along the tideline. We must be sure to mention the ocean conditions. On Pournami (full-moon) day, they announced that a depression was forming in the Indian Ocean. The last three days testify to that. The waves have been so rough that no fisher has ventured out to sea. I say this is extraordinary because just in the span of six years, I have witnessed two such never-seen-before incidents on my beach. The sea is not what it used to be.”Palayam’s flagging of the netti phenomenon as noteworthy merits attention as it adds to the growing list of indicators that the sea has changed – a commonly heard lament along India’s coast. In 2019, it was not just Palayam but others too, like naturalist M. Yuvan, who reported the blue button strandings as noteworthy. Palayam’s observations carry particular weight because, over his lifetime of daily immersion in the Urur littoral, this stranding stands out as exceptional. “What,” I ask Palayam, “do you think is the cause of these increasingly frequent strandings?” He replied wryly: “Brother, we have been saying that the sea has changed because of all the bad things we have done on land. What are we going to do about changing what we do on land? That is the important question.”S. Palayam is a veteran hook-and-line fisher and fisher scientist. Nityanand Jayaraman is a writer, social activist and citizen science enthusiast.