Effects of Nautical Traffic and Noise on Foraging Patterns of Mediterranean Damselfish (Chromis chromis)

Abstract

Chromis chromis is a key species in the Mediterranean marine coastal ecosystems where, in summer, recreational boating and its associated noise overlap. Anthropogenic noise could induce behavioural modifications in marine organisms, thereby affecting population dynamics. In the case of an important species for the ecosystem like C. chromis, this could rebound on the community structure. Here, we measured nautical traffic during the summer of 2007 in a Southern Mediterranean Marine Protected Area (MPA) and simultaneously the feeding behaviour of C. chromis was video-recorded, within both the no-take A-zone and the B-zone where recreational use is allowed. Feeding frequencies, escape reaction and school density were analysed. C. chromis specimens were also collected from 2007 to 2008 to evaluate their physiological state using the Body Condition Index as a proxy of feeding efficiency. The MPA was more exploited by nautical tourism during holidays than on weekdays, particularly in the middle of the day. Greater traffic volume corresponded with lower feeding frequencies. The escape reaction was longer in duration (>1 min) when boat passed nearby, while moored boats did not induce an escape response. We found no differences in density between schools in the A- and B-zones and worse body conditions among those individuals inhabiting the B-zone in one area only. Overall, our findings revealed a significant modification of the daily foraging habits of C. chromis due to boat noise, which was slightly buffered by no-take zones established within the MPA.

Effects of motorboat noise on foraging behaviour in Eurasian perch and roach: a field experiment

“…In perch, the same pattern was found in the single-, but not in the mixedspecies enclosures. Lower feeding frequencies and changes in diet composition have previously been ob served in both the Mediterranean damselfish Chromis chromis and the mulloway Argyrosomus japonicus during periods of increased boating activity (Bracciali et al 2012, Payne et al 2015. The altered mulloway behaviour was suggested to be caused by stress, which is a common consequence of noise disturbance (Kight & Swaddle 2011).…”

“…Experiments on the effects of noise disturbance on foraging are rarely conducted outdoors (but see Bracciali et al 2012, Payne et al 2015. Thus, our study is among the first to study noise effects in fish under natural environmental conditions.…”

“…Reduction in feeding rates in connection with increased boating activity has been found in mulloway Argyrosomus japonicus (Payne et al 2015) and in damselfish Chromis chromis (Bracciali et al 2012). Both three-spined stickleback Gasterosteus aculeatus (Purser & Radford 2011) and zebrafish Danio rerio (Shafiei Sabet et al 2015) showed increased food-handling errors when exposed to sound.…”

Monitoring the habitat use of common Bottlenose Dolphins (Tursiops truncatus) using passive acoustics in a Mediterranean marine protected area

“…This behaviour could be explained in different ways. For instance, if animals perceive a threatening situation, they are more likely to adopt evasive tactics similar to those observed when escaping a predator (Lima & Dill, 1990;Bracciali et al, 2012). A significant effect on habitat use as a result of disturbance from increasing boat traffic has been observed in other sites (Corkeron, 1995;Allen & Read., 2000;Lusseau, 2003Lusseau, , 2005Lamb & Ugarte, 2005;Sousa-Lima & Clark, 2008) such as in Lampedusa Island (Papale et al, 2011;La Manna et al, 2013).…”

“…In the last decades, boat traffic has increased exponentially in the Mediterranean Sea (Abdulla & Linden, 2008) leading to a parallel rise in noise and related effects on local fauna (e.g. Bracciali et al, 2012). Nevertheless, the effects on Mediterranean habitat use and behaviour of T. truncatus have never been studied in detail and very little data has been published in peer-reviewed journals.…”