A Tough Fish Undaunted by Land

Dave Taft Glass eels in Staten Island.

Even in an environment as man-made as New York City’s, nature stubbornly persists â€" in park woodlands, empty lots and between the cracks of the sidewalk. In an occasional series, Dave Taft, a senior-level park ranger in New York City with the National Park Service, will be offering close-in portraits of the city’s plants and animals.

The Atlantic salmon and American eel each makes an epic voyage, but an eel’s greenish color, snakelike proportions and bottom-dwelling habits make it harder to love than a gleaming silver salmon. In terms of relative abundance and sheer toughness, the hands-down winner is the lowly American eel (Anguilla rostrata).

Salmon and eels find homes in fresh and salt water, but from there the two diverge. Salmon are “anadromous”: They begin life in fresh water and journey to the sea to reach adulthood. Eels are “catadromous”: Every American eel is born in the Sargasso Sea, in an area of the Atlantic south of Bermuda, and then swims thousands of miles to ascend the smallest of freshwater creeks to spend its adult life.

Eels do not require the cold, pristine streams that salmon do, and can surprisingly be found in landlocked ponds and lakes, in all five boroughs. Adults can make pilgrimages of hundreds of yards overland to find water in dry periods and can remain alive for hours provided that their gills remain damp. Juvenile eels are proficient climbers and can clamber up out of the water and over low obstructions during migration. Here in New York City, where the process of damming of creeks dates hundreds of years to the Dutch and English, a few creeks even now entertain spawning runs.

Beginning in March and tapering off in mid- May, juvenile eels, who have spent the fall and winter drifting with the ocean currents from the Sargasso, swim off to make their way up coastal waterways along the East Coast. They are as soft as an earthworm and about the same size, and there is hardly a fish, mammal or bird that is not interested in an eel-meal. So the eels travel by night.

If this weren’t enough to ensure safe passage, they employ another trick: larval eels are transparent, earning them the name “glass eels.” Upon entering fresh water, they begin their transformation to more respectable eel-like colors, but initially they are the ghosts of the fish world, invisible against the nighttime bottoms of the still frigid northeast waters.

I grew up on the southern edge of Brooklyn and caught many eels with my brother while fishing in places like Sheepshead Bay. There was a particular thrill to catching the three-feet-long eels â€" their writhing bodies impossible to grip for their thick mucus slime.

Once they were hoisted onto land, their frenzied thrashing was both thrilling and shocking, especially to a pair of 11-year-old boys well acquainted with trouble.

Another favorite pastime was overturning the flat stones found at the head of the Mill Basin or one or two other local creeks to hunt for young eels, or “elvers.” We might have thought more about these catches â€" eels are highly prized by more than other fish and birds, there’s serious money in those wriggling bodies. The still-clear glass eels hit $2,000 a pound on the Asian market in 2012. With prices like these, it is no wonder this fish is now imperiled.