As this report was nearing completion I found myself describing the remarkable lifecycle of the longfin eel to an acquaintance. At the end of a long life, longfin eels leave their freshwater homes to journey for thousands of kilometres north through the Pacific to breed somewhere near Fiji. The eggs hatch into transparent leaf-like larvae which drift on ocean currents all the way back to New Zealand. The larvae turn into tiny ‘glass eels’ and begin to swim up rivers and streams. Glass eels become elvers and these small wriggling slender fish continue to swim upstream in shoals until they find a place to call home. Here they stay and grow for many years until heeding the call to breed. Then an almost magical transformation takes place to prepare them for their great sea journey – their heads become streamlined, their eyes turn blue, their bellies turn silver.
At this point my acquaintance, a recreational fisherman, stopped me aghast. He realised that the giant silver-bellied creature he had once caught in a harbour must have been a longfin eel, and that he had killed it just before it was about to breed after decades of growth. It was an ignominious end for a creature that had likely lived longer than most people, and that belonged to a species that exists nowhere else on earth and is so interwoven with our history.
The first Polynesians to arrive in New Zealand must have been astounded to find themselves dwarfed by moa. But lurking in the depths were more giants – snakelike fish they called tuna that would grow to the width of a man’s thigh, up to two meters long, and live as long as a hundred years. Eels became an important food source for Māori, but it was a relationship that extended beyond nourishment to respect, and even reverence. Over time they were even thought of as protectors or guardians.