An expedition team in New Zealand came across a group of remarkable eels before the animals set off on a migration of over 1,000 miles to breed.
"The New Zealand longfin eel (Anguilla dieffenbachii) is the country’s largest and only endemic freshwater eel, with an extraordinary life cycle,” says Andi Cross, expedition lead at Edges of Earth.
"These eels spend between 25 and 80 years in rivers, lakes and wetlands before making a single, epic migration to breed.”
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From New Zealand, they travel all the way to Tonga where the females lay their eggs in deep waters, which are fertilised by the males. This is how the animals end their lifecycle: after breeding, they die. When the eggs hatch, the larvae float back to New Zealand on ocean currents. There “they begin the cycle anew,” Cross says.
"Known as tuna in Māori, longfin eels are a cultural treasure (taonga) with deep historical and ecological significance,” adds Cross. “But their future is uncertain – habitat loss, overfishing and environmental pressures have led to population declines, making conservation efforts more critical than ever.”
Image and video credit: Edges of Earth
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