The northern pygmy squid (Idiosepius paradoxus) may be tiny—at just 4 to 18 millimeters, it would fit on the tip of your finger—but its unusual and delicate egg-laying ritual made a big impression on underwater photographer Tony Wu.

As this female pygmy squid began readying her nest site in the shallow waters off Japan’s southern coast, Wu zoomed in to capture the event. First, she dusted off a blade of eelgrass with her arms. Then, with graceful precision, she laid the jelly-coated eggs onto the newly clean surface, one by one. But laying the eggs is not the female’s only job—she must fertilize them too. Northern pygmy squids do not copulate, exactly; instead, according to a 2014 study, a male latches packets of fishhook-shaped sperm, called spermatophores, onto a female’s body, and the sperm gradually migrate to a receptacle near her mouth. Wu watched as this mother pygmy squid bit a small opening in each egg and injected it with a tiny bit of sperm from her stash. As she prepared to lay another egg, Wu clicked the shutter.

“Watching the female prepare the seagrass and deposit each egg with such tenderness and care (love?) was an emotional experience,” Wu says. “These squids are far more complex and nuanced than I had assumed.”

The northern pygmy squid—one of the smallest cephalopods on Earth—is native to the western Pacific Ocean, off the coast of Japan, northern Australia, and South Korea. It also can be found in the Pacific Ocean near Indonesia.

Yamaguchi Prefecture, Japan

Tony Wu

Tony Wu combines his love of visual art with his interest in the marine world through underwater photography. Since 1995, Wu has used his photographs and writing to encourage others to appreciate and protect the beauty of the oceans. Most recently, he’s devoted his attention to photographing whales and other cetaceans, as well as mass spawning aggregations of fish. His images have received international awards in Japan, Europe, and the US, including Grand Prize in Japan’s largest marine photo contest and first place in the underwater category of the Wildlife Photographer of the Year competition.

April Reese

April Reese is a freelance science writer and editor based in Santa Fe, New Mexico. Her reporting from the Southwest and around the world has appeared in Scientific American, Discover, bioGraphic, Science magazine, Nature, Aeon, High Country News, and many other outlets. She holds a master's degree in Environmental Studies from the Yale School of the Environment.

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