Figure 2.

Swimming respirometry of chub (Leuciscus cephalus) following exposure in submerged cages to two sites on the river Lambro, Italy: a relatively clean site (Merone) or a polluted site (Brugherio). Results from (a) June 2001 and (b) September 2001. The graphs show mean (±s.e.m.) RMR measured prior to the exercise challenge on fish swimming steadily at 20 cm s⁻¹, the AMR achieved during the exercise challenge and the functional aerobic scope for activity (ASA) calculated as AMR–RMR. Each variable was measured twice, with the second swim test (T2, open columns) measured 40 min following fatigue in the first swim test (T1, filled columns). In all cases, n=6. Asterisk, significant difference between T1 and T2 for that river site in that campaign; dagger, significant difference between the two sites for the relevant variable in that campaign.