Ontogenetic and interspecific variation in hearing ability in marine fish larvae

Abstract

In most demersal marine teleost fishes, larvae develop in the pelagic environment, but must locate appropriate settlement habitats. One potential cue for locating settlement habitats that has received recent interest is acoustic cues from reef habitats. Although it is clear that settlement-stage fish larvae can hear, it is less clear how hearing ability develops during the larval phase, or how auditory abilities vary among species and families. Auditory-evoked potentials were used to investigate hearing in larvae of 5 fishes (Epinephelus coioides, E. fuscoguttatus, Serranidae; Eleutheronema tetradactylum, Polynemidae; Caranx ignobilis, Carangidae; and Macquaria novemaculeata, Percichthyidae) over a range of sizes (9 to 28 mm). Ontogenetic improvement in hearing of up to 25 dB was found in 4 species. We also assessed hearing ability within and between 4 families (Serranidae, Lutjanidae, Pomacentridae and Carangidae) using larger larvae of 11 species from tropical and warm temperate habitats (the serranids and carangid above plus Epinephelus malabaricus, Plectropomus leopardus, Lutjanus carponotatus, L. sebae, Pomacentrus nagasakiensis, P. amboinensis, Gnathanodon speciosus and Elagatis bipinnulata). Within pomacentrids, carangids and lutjanids, hearing sensitivity differences among species were found. This high within-family variance results in no difference in hearing ability among the 4 families. A key component of modelling reef connectivity is the estimation of larval attraction distances. The data provided herein clearly demonstrate that attraction varies both ontogenetically and among species. Both developmental stage and species must be taken into account when estimating distances over which sound cues emanating from settlement habitats can be detected. © Inter-Research 2011.