Nearly 20 years ago, while researching tide pools, I came across Rachel Carson’s 1941 book Under the Sea Wind. The book includes a fascinating chapter on American eels, and I was hooked. Eels begin their lives in the Sargasso Sea, a vast area of the Atlantic Ocean near Bermuda. Their tiny, leaf-shaped larvae drift on ocean currents for a year or more before metamorphosing into clear glass eels as they approach the coasts of eastern North and South America. When they reach river mouths, they transform again, shifting from ocean travelers into young freshwater fish known as elvers. Elvers head upstream and grow into yellow eels, which spend six to 20 years or more living in rivers, streams, and connected lakes and ponds, hunting at night and hiding by day.

Then, one night in late fall, the mature yellow eel feels the urge to return to the ocean. Along the way, it transforms again, becoming a sleek black-and-silver silver eel adapted for the ocean and ready to breed. These eels swim thousands of miles back to their birthplace in the Sargasso Sea, where they spawn and die.

That journey still feels almost impossible to picture: an animal that changes bodies, habitats, and instincts as it moves between sea and stream, only to find its way back across the open Atlantic.

There’s far more to the story—and to the research that revealed the eel’s complex life cycle. What fascinates me most is knowing that creatures beyond our wildest imaginings exist. They fill our world with beauty and mystery, and they are part of the interdependent webs of life on which we depend.

I did this piece during the Wild Wonder Nature Journaling Conference, which took place this week. Thanks to those of you who took the deeper dive with me!