Variability in growth of longfinned eels among coastal catchments of south-eastern Australia

Longfinned eels Anguilla reinhardtii were captured by both fishery-dependent and independent sampling methods from three rivers in New South Wales. south-eastern Australia. Growth rates were examined in two zones (fresh water and tidal) in the Hacking. Hawkesbury and Clarence Rivers. Mean annual growth increments of sampled longfinned eels ranged front 30 to 60 mm year(-1) using age-length analyses and up to 167 mm year(-1) based on tag-recapture model estimates (GROTAG), with both methods showing high intra- and inter-population variability. Growth was significantly faster in younger (5-15 years) fish than older (> 15 years) fish, with females growing an average 10 mm year(-1) faster than males of similar age and capture location. Longfinned eels found in tidal areas grew significantly faster than those in non-tidal freshwater areas as a result of longer growing seasons in the highly productive estuarine habitats. Other possible factors influencing variability in growth rates for this species include habitat preference, density and fishing pressure. (c) 2006 The Fisheries Society of the British Isles.