On the geographical map, the Chatham Islands almost seem like a detail that slipped away from New Zealand. A group of distant islands, battered by the Pacific, with more wind than noise and enough distance from the rest of the country to make it seem like an edge. Then a satellite image arrives and that edge becomes a luminous circle: greens and blues that envelop the archipelago, as if the sea had lit a lamp around the earth.
The photograph was taken on January 10, 2026 by the NOAA-20 satellite, through the VIIRS instrument, the radiometer used to observe oceans, atmosphere and land surfaces. What ended up in the image was a large bloom of phytoplankton, that is, microscopic photosynthetic organisms which, when they proliferate in enormous quantities, become visible even from space. The surface currents and marine vortices have stretched that living mass into filaments, spirals, thin strips, to build a ring around the islands.
The coordinates are around 44 degrees south and 176.5 degrees west, about 800-840 kilometers east of the South Island of New Zealand, off the east coast where Christchurch is located. The archipelago has ten main and secondary islands. The two largest are Chatham Island, about 58 kilometers wide, and Pitt Island, about 15 kilometers; the others are much smaller and in the orbital image they almost disappear into the color of the sea.
The seabed that pushes cold water and nutrients to the surface
The glow, seen from above, seems like an aesthetic oddity. The mechanism that produces it works much lower down, where the ocean meets the geology. The Chatham Islands rest on the Chatham Rise, a vast underwater plateau that stretches eastward from New Zealand for approximately 1,450 kilometers. Its top is relatively shallow compared to the sea basins that surround it, and this shape of the seabed modifies the movement of the water. There, cold, nutrient-rich currents from the Antarctic area and warmer, nutrient-poor subtropical water masses meet. The result, during the southern summer, can become explosive: well-mixed water, long hours of light and microorganisms ready to multiply.
The bloom observed in January 2026 is part of a known phenomenon along the Chatham Rise, although its near-circular shape and spread made it particularly noticeable. A significant part of these blooms is associated with coccolithophores, a group of phytoplankton capable of building tiny calcium carbonate plates around the cell. En masse, these structures function like very clear dust suspended in the sea: they reflect light, lighten the water, produce those milky shades between green and blue that satellites read with great precision. In some processing the near infrared bands can make the colors even clearer, but the substance remains concrete: millions and millions of living organisms, brought to the surface by an enormous oceanic machine.
Phytoplankton occupy the base of the pelagic food web, that of the open sea. On land the role falls to plants; in the ocean, most often, to these microscopic organisms that transform light, nutrients and carbon dioxide into energy available for the rest of marine life. Where phytoplankton grows, everything else grows: small animals, fish, predators, seabirds, mammals. The waters around the Chatham Islands support important fisheries, with species such as pāua, rock lobster and blue cod, and are also home to a wide variety of marine mammals.
On land, Pitt Island features rugged coastlines and ridges such as Mount Hakepa, frequented by thousands of seabirds. At sea, the picture expands: penguins, albatrosses, seals, sea lions, commercially valuable fish, and at least 25 species of cetaceans, including whales and dolphins. The group includes killer whales, sperm whales and pilot whales. The sea that nourishes, however, also presents a trap here.
Where food arrives, whales, orcas and dolphins also arrive
The same geography that makes these waters productive contributes to making them one of the most delicate places for strandings. Shallow water, difficult shorelines, tides and acoustic orientation can turn a feeding area into a funnel. Cetaceans come in to feed, they move in groups, they follow signals that work very well in the open sea and can become confused near the coast. When they get too close to shore, the retreating tide can leave them stranded on the sand. At that point time becomes cruel.
The Chatham Islands have long been known for events of this type. In October 2022, the New Zealand Department of Conservation intervened after two mass strandings that occurred a few days apart: around 240 pilot whales ended up stranded on October 7 in the northwestern part of Rēkohu/Wharekauri/Chatham Island, and almost another 240 beached on October 10 in Waihere Bay, on Rangihaute/Rangiauria/Pitt Island. Some animals were already dead when help arrived; the others were killed to reduce suffering, also because on those islands recovery at sea is avoided due to the high risk of shark attacks on people and cetaceans.
The historical data weighs even more. In 1918, again on the Chatham Islands, an estimated 1,000 pilot whales died in what remains one of the largest mass strandings recorded. The pilot whale, although often called the “pilot whale”, actually belongs to the delphinid family. It is a highly social animal, and this very cohesion can become a condemnation: when an injured, sick or disoriented individual takes a wrong trajectory, the group can follow him to the shore.
The image from January 2026, therefore, holds together two sides of the same marine structure. On the one hand there is the productive sea, lit by phytoplankton, capable of supporting biodiversity and fishing. On the other there is an archipelago which, precisely because it is rich in life, attracts large and social animals into waters where the error of orientation can cost hundreds of deaths. The greenery seen from space is beautiful. Up close also brings the heavy smell of carcasses on the beach.
An archive of recent extinctions, including lost birds and bones left in the sand
The history of the Chatham Islands remains fragile even out of the water. The archipelago has hosted numerous endemic species, which have grown in isolation and are therefore particularly vulnerable to the arrival of new pressures. According to the Department of Conservation, at least 52 native bird species nest or have nested on the islands, with a significant proportion found only there. The transformations following human colonization have had a profound impact: around 14 species became extinct after the arrival of the Moriori, the first inhabitants of the islands, and others disappeared later with the arrival of Europeans and Māori, in a context marked by introduced predators, human extraction and loss of habitat.
Among these absences there is also the Chatham Islands crested penguin (Eudyptes warhami), known through subfossil remains found in coastal dunes and archaeological sites. Bones found in middens, i.e. ancient food waste deposits, indicate that it was hunted and consumed. Genetic studies later confirmed that it was a distinct species, endemic to the archipelago. Its extinction is linked to the human pressure exerted by the first settlements.
This layering makes the Chatham Islands a less simple place than the photography suggests. In the satellite image you can see a green crown, an almost elegant geometry, a natural phenomenon large enough to be noticed from hundreds of kilometers above sea level. Below there are currents that mix cold and warm waters, seabeds that guide nutrients, microorganisms covered in calcium carbonate, fish, birds, seals, whales, beaches that sometimes become traps, bones of disappeared species.
The space gives everything back in one fell swoop, clean, almost ornamental. The sea, on the other hand, works without decorations. It nourishes, attracts, confuses, preserves. And every now and then he draws a ring so beautiful it seems innocent.
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