ABOVE: A longfin eel (Sourced from Wikimedia commons)

There are two species of eel in New Zealand. These are the shortfin and longfin eels. The two species can be distinguished by the length of their dorsal (top) fins. The shortfin eel’s dorsal fin is equal in length to the cloacal (bottom) fin, whereas the longfin eel’s dorsal fin is about twice as long as the cloacal fin. Longfin eels are found only in New Zealand and are surprisingly agile. Adult eels can climb out of freshwater bodies and move across land when needed. They are also long-lived, with some eels living up to and exceeding 100 years. While they will inhabit estuaries, rivers, lakes, and wetlands throughout New Zealand for most of their lives, they will migrate to the South Pacific Ocean, just south of Tonga to lay their eggs and die. Ocean currents pull the eggs back to New Zealand after about 15 months at sea.