Ocean acidification boosts larval fish development but reduces the window of opportunity for successful settlement

• Main Authors: Rossi, Tullio, Nagelkerken, Ivan, Simpson, Stephen D, Pistevos, Jennifer C A, Watson, Sue-Ann, Merillet, Laurene, Fraser, Peter, Munday, Philip L, Connell, Sean D
• Format: Dataset
• Language: English
• Published: PANGAEA 2015
• Subjects: Alkalinity; total; standard error; Animalia; Aragonite saturation state; Behaviour; Bicarbonate ion; Calcite saturation state; Calculated using CO2SYS; Calculated using seacarb after Nisumaa et al. (2010); Carbon; inorganic; dissolved; Carbonate ion; Carbonate system computation flag; Carbon dioxide; Chordata; Coast and continental shelf; Containers and aquaria (20-1000 L or < 1 m**2); Fugacity of carbon dioxide (water) at sea surface temperature (wet air); Growth/Morphology; Identification; Laboratory experiment; Lates calcarifer; Length; standard; Nekton; OA-ICC; Ocean Acidification International Coordination Centre; Partial pressure of carbon dioxide (water) at sea surface temperature (wet air); Pelagos; pH; Phase; Registration number of species; Replicates; Salinity; Single species; South Pacific; Species; Speed; swimming; Status; Ocean acidification
• Online Access: https://doi.pangaea.de/10.1594/PANGAEA.868507; https://doi.org/10.1594/PANGAEA.868507

Locating appropriate settlement habitat is a crucial step in the life cycle of most benthic marine animals. In marine fish, this step involves the use of multiple senses, including audition, olfaction and vision. To date, most investigations of larval fish audition focus on the hearing thresholds to various frequencies of sounds without testing an ecological response to such sounds. Identifying responses to biologically relevant sounds at the development stage in which orientation is most relevant is fundamental. We tested for the existence of ontogenetic windows of reception to sounds that could act as orientation cues with a focus on vulnerability to alteration by human impacts. Here we show that larvae of a catadromous fish species (barramundi, Lates calcarifer) were attracted towards sounds from settlement habitat during a surprisingly short ontogenetic window of approximately 3 days. Yet, this auditory preference was reversed in larvae reared under end-of-century levels of elevated CO2, such that larvae are repelled from cues of settlement habitat. These future conditions also reduced the swimming speeds and heightened the anxiety levels of barramundi. Unexpectedly, an acceleration of development and onset of metamorphosis caused by elevated CO2 were not accompanied by the earlier onset of attraction towards habitat sounds. This mismatch between ontogenetic development and the timing of orientation behaviour may reduce the ability of larvae to locate habitat or lead to settlement in unsuitable habitats. The misinterpretation of key orientation cues can have implications for population replenishment, which are only exacerbated when ontogenetic development decouples from the specific behaviours required for location of settlement habitats.