Quantification of the maximal swimming performance of Australasian glass eels, Anguilla australis and Anguilla reinhardtii, using a hydraulic flume swimming chamber

Abstract

The swimming performance of Australasian glass eels Anguilla australis Richardson and Anguilla reinhardtii Steindachner was measured within an hydraulic flume over a range of water velocities. Individual swimming performances were characterised as either maximum sustained, steady prolonged, rapid prolonged, or burst. The maximum sustained swimming speeds for A. australis (mean total length (MTL) = 54.2 mm) and A. reinhardtii (MTL = 51.2 mm) were 29 and 32 cm s‐1 respectively. The maximum burst speeds for A. australis and A. reinhardtii were 79 and 75 cm s‐1 respectively. Regression analysis revealed two points of inflection corresponding to definite changes in the level of swimming effort occurring at 35 and 64 cm s‐1 for A. australis, and 42 and 63 cm s‐1 for A. reinhardtii. Observed differences in the swimming performance of these two species was not significant (P < 0.05). To allow free passage for migrating glass eels in Queensland's regulated rivers, this study recommends that mean and maximum fishway velocities not exceed 30 and 75 cm s‐1 respectively, and/ or fishway cells be designed to incorporate elements specifically designed to permit glass eel passage.