Journal Article

Effects of ocean acidification on visual risk assessment in coral reef fishes

Munday, Philip L., Ferrari, Maud C. O., McCormick, Mark I., Meekan, Mark G., Chivers, Douglas P., Dixson, Danielle L., Lönnstedt, Oona

2012

Overview

1. With the global increase in CO 2 emissions, there is a pressing need for studies aimed at understanding the effects of ocean acidification on marine ecosystems. Several studies have reported that exposure to CO 2 impairs chemosensory responses of juvenile coral reef fishes to predators. Moreover, one recent study pointed to impaired responses of reef fish to auditory cues that indicate risky locations. These studies suggest that altered behaviour following exposure to elevated CO 2 is caused by a systemic effect at the neural level. 2. The goal of our experiment was to test whether juvenile damselfish Pomacentrus amboinensis exposed to different levels of CO 2 would respond differently to a potential threat, the sight of a large novel coral reef fish, a spiny chromis, Acanthochromis polyancanthus, placed in a watertight bag. 3. Juvenile damselfish exposed to 440 (current day control), 550 or 700 μatm CO 2 did not differ in their response to the chromis. However, fish exposed to 850 μatm showed reduced antipredator responses; they failed to show the same reduction in foraging, activity and area use in response to the chromis. Moreover, they moved closer to the chromis and lacked any bobbing behaviour typically displayed by juvenile damselfishes in threatening situations. 4. Our results are the first to suggest that response to visual cues of risk may be impaired by CO 2 and provide strong evidence that the multi-sensory effects of CO 2 may stem from systematic effects at the neural level.

• Publisher: Blackwell Publishing,Blackwell Publishing Ltd,Wiley-Blackwell,Wiley Subscription Services, Inc
• Subject: acidification / Agnatha. Pisces / Animal and plant ecology / Animal, plant and microbial ecology / Autoecology / bags / Behavioural ecology / Biological and medical sciences / carbon dioxide / Coral reefs / ecosystems / emissions / Fish / foraging / Fundamental and applied biological sciences. Psychology / General aspects / Human ecology / Marine ecology / Marine fishes / Ocean acidification / Oceans / Pomacentridae / Pomacentrus amboinensis / Predators / predator–prey interactions / risk / risk assessment / Sea water / Vertebrates: general zoology, morphology, phylogeny, systematics, cytogenetics, geographical distribution / visual cues / Young animals