title: Lost at sea: ocean acidification undermines larval fish orientation via altered hearing and marine soundscape modification.
abstract: The dispersal of larvae and their settlement to suitable habitat is fundamental to the replenishment of marine populations and the communities in which they live. Sound plays an important role in this process because for larvae of various species, it acts as an orientational cue towards suitable settlement habitat. Because marine sounds are largely of biological origin, they not only carry information about the location of potential habitat, but also information about the quality of habitat. While ocean acidification is known to affect a wide range of marine organisms and processes, its effect on marine soundscapes and its reception by navigating oceanic larvae remains unknown. Here, we show that ocean acidification causes a switch in role of present-day soundscapes from attractor to repellent in the auditory preferences in a temperate larval fish. Using natural CO2 vents as analogues of future ocean conditions, we further reveal that ocean acidification can impact marine soundscapes by profoundly diminishing their biological sound production. An altered soundscape poorer in biological cues indirectly penalizes oceanic larvae at settlement stage because both control and CO2-treated fish larvae showed lack of any response to such future soundscapes. These indirect and direct effects of ocean acidification put at risk the complex processes of larval dispersal and settlement.
authors.affiliation: Southern Seas Ecology Laboratories, School of Biological Sciences and the Environment Institute, The University of Adelaide, DX 650 418, Adelaide, South Australia 5005, Australia.
authors.forename: Tullio
authors.initials: T
authors.lastname: Rossi
authors.affiliation: Southern Seas Ecology Laboratories, School of Biological Sciences and the Environment Institute, The University of Adelaide, DX 650 418, Adelaide, South Australia 5005, Australia ivan.nagelkerken@adelaide.edu.au.
authors.forename: Ivan
authors.initials: I
authors.lastname: Nagelkerken
authors.affiliation: Southern Seas Ecology Laboratories, School of Biological Sciences and the Environment Institute, The University of Adelaide, DX 650 418, Adelaide, South Australia 5005, Australia.
authors.forename: Jennifer C A
authors.identifier: http://orcid.org/0000-0001-8081-7069
authors.initials: JC
authors.lastname: Pistevos
authors.affiliation: Southern Seas Ecology Laboratories, School of Biological Sciences and the Environment Institute, The University of Adelaide, DX 650 418, Adelaide, South Australia 5005, Australia.
authors.forename: Sean D
authors.initials: SD
authors.lastname: Connell
mesh_terms: D000162:Acoustics; D000818:Animals; D001522:Behavior, Animal / Q000502:physiology; D002245:Carbon Dioxide; D003463:Cues; D005399:Fishes / Q000502:physiology*; D006309:Hearing / Q000502:physiology; D060086:Hydrothermal Vents; D007814:Larva / Q000502:physiology; D009792:Oceans and Seas; D012623:Seawater / Q000737:chemistry*; D013016:Sound
chemical_list: D002245:Carbon Dioxide
keywords: larval dispersal; mulloway; population replenishment; settlement; snapping shrimps; sound