Sustained swimming abilities of the late pelagic stages of coral reef fishes

The sustained swimming abilities of the late pelagic stages of 9 families of reef fishes were measured at 13.5 cm S ' There was a 25-fold difference in abilities among the families. Acanthurid juveniles swam on average for 194 3 h, covering the equivalent of 94.4 km. In comparison nemipterids swam for only 7.4 h, the equivalent of 3.6 km. The distances covered by other taxa ranged from 8 3 to 62.2 km. Among the families swimming ability was related to size and age but this relationship explained little of the variation present (R2 = 0.403). Our results demonstrate that the pelagic stages of reef fishes are competent swimmers and capable of actively modifying their dispersal. This has direct implicat~ons on the replenishment of reef fish populations, especially with respect to mechanisms for self-seeding and maintenance of regional biogeographical patterns.