Preliminary observations of migrating adult freshwater eels (Anguilla australis australis Richardson) in Tasmania

Abstract

The downstream migration of maturing adult short-finned eels, A. a. australis, was recorded at an eel trap on the Clyde River during the 1981-1982 season. 5.2 t of eels entered the trap from November to April with 53% of the catch taken during January. Of the 190 eels examined, only a single male specimen was found. Female A. a. australis migrated downstream at a mean length of 94.5 cm, a mean weight of 1700 g and a mean age of 22.1 years (range 18-30 years). There was a significant positive correlation between catch and water temperature, temperatures above 12ºC being associated with eel migration. The peak catch occurred during January and coincided with the highest record of mean daily water temperature (20.5ºC). The migration did not appear to be influenced by moon phase, and river flow was controlled.