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Acoustic noise induces attention shifts and reduces foraging performance in three-spined sticklebacks (Gasterosteus aculeatus).

Purser J, Radford AN - PLoS ONE (2011)

Bottom Line: The addition of noise induced only mild fear-related behaviours--there was an increase in startle responses, but no change in the time spent freezing or hiding compared to a silent control--and thus had no significant impact on the total amount of food eaten.However, there was strong evidence that the addition of noise increased food-handling errors and reduced discrimination between food and non-food items, results that are consistent with a shift in attention.Consequently, noise resulted in decreased foraging efficiency, with more attacks needed to consume the same number of prey items.

View Article: PubMed Central - PubMed

Affiliation: School of Biological Sciences, University of Bristol, Bristol, United Kingdom. julia.purser@bristol.ac.uk

ABSTRACT
Acoustic noise is known to have a variety of detrimental effects on many animals, including humans, but surprisingly little is known about its impacts on foraging behaviour, despite the obvious potential consequences for survival and reproductive success. We therefore exposed captive three-spined sticklebacks (Gasterosteus aculeatus) to brief and prolonged noise to investigate how foraging performance is affected by the addition of acoustic noise to an otherwise quiet environment. The addition of noise induced only mild fear-related behaviours--there was an increase in startle responses, but no change in the time spent freezing or hiding compared to a silent control--and thus had no significant impact on the total amount of food eaten. However, there was strong evidence that the addition of noise increased food-handling errors and reduced discrimination between food and non-food items, results that are consistent with a shift in attention. Consequently, noise resulted in decreased foraging efficiency, with more attacks needed to consume the same number of prey items. Our results suggest that acoustic noise has the potential to influence a whole host of everyday activities through effects on attention, and that even very brief noise exposure can cause functionally significant impacts, emphasising the threat posed by ever-increasing levels of anthropogenic noise in the environment.

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Related in: MedlinePlus

Ambient noise in standard pre-trial housing tanks.Ambient sound pressure levels (spectral density, dB/Hz re 1 µPa) from averaged power spectra (FFT analysis: spectral level units, Hann evaluation window, 50% overlap, FFT size 1024) recorded in standard stock tanks used for housing stickleback prior to studies (AS), ambient conditions in still freshwater test tanks (AT), and ambient conditions in an example freshwater lake in the UK (AL).
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pone-0017478-g001: Ambient noise in standard pre-trial housing tanks.Ambient sound pressure levels (spectral density, dB/Hz re 1 µPa) from averaged power spectra (FFT analysis: spectral level units, Hann evaluation window, 50% overlap, FFT size 1024) recorded in standard stock tanks used for housing stickleback prior to studies (AS), ambient conditions in still freshwater test tanks (AT), and ambient conditions in an example freshwater lake in the UK (AL).

Mentions: Twenty-four adult three-spined sticklebacks were used as subjects, with an additional twelve individuals (familiar to the subjects) used as companion fish; presence of a ‘companion’ fish in proximity to the focal fish aids normal behaviour of the focal fish during testing (stickleback are housed in stable social groups). Fish were wild-caught in a UK river by a reputable biological supplier. Prior to experimental testing, fish were acclimated to the captive environment in the indoor fish facilities at the University of Bristol: groups of up to 20 sticklebacks were housed in 100 l stock tanks with an air sponge and external power filtration, at 10°C on a 12:12 light dark cycle (keeping the fish in non-breeding winter condition), and fish were fed three times per week on frozen bloodworm (Chironomid larvae). Care was taken to minimise the intrusion of artificial noise into the stock tanks, particularly with regard to frequencies below 2 kHz, which are in the possible hearing range of fish, such as the three-spined stickleback (see [35] for an audiogram of another Gasterosteidae, the nine-spined stickleback Pungitius pungitius), that have a swim bladder but no known hearing “specializations” [36]. Fish were housed in tanks placed on thick polystyrene boards in thermally insulated rooms, within a building separate from the associated University building (minimising the transmission of low-frequency external building noises); external power filters were placed on a separate base (minimising transmission of low-frequency filter noise); power filter outflows were piped underneath the water surface (minimising noisy disruption of the water surface); and sponge filter air flows were at low pressure (minimising low-frequency noise from filter vibration and high-frequency noise from air bubbles). The resulting ambient sound levels, at frequencies below 2 kHz, were slightly higher in standard pre-trial housing tanks than the ambient acoustic conditions in still freshwater test tanks (with no filtration or air flow; median difference of sound pressure level (SPL) in 43 Hz steps from 43–1938 Hz (spectral density, dB/Hz): 7 dB re 1 µPa; Figure 1) and an example freshwater lake habitat (median difference: 9 dB re 1 µPa; Figure 1), but comparable to freshwater streams and rivers reported in [37] that are typical of the habitat where the study species lives naturally.


Acoustic noise induces attention shifts and reduces foraging performance in three-spined sticklebacks (Gasterosteus aculeatus).

Purser J, Radford AN - PLoS ONE (2011)

Ambient noise in standard pre-trial housing tanks.Ambient sound pressure levels (spectral density, dB/Hz re 1 µPa) from averaged power spectra (FFT analysis: spectral level units, Hann evaluation window, 50% overlap, FFT size 1024) recorded in standard stock tanks used for housing stickleback prior to studies (AS), ambient conditions in still freshwater test tanks (AT), and ambient conditions in an example freshwater lake in the UK (AL).
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC3046255&req=5

pone-0017478-g001: Ambient noise in standard pre-trial housing tanks.Ambient sound pressure levels (spectral density, dB/Hz re 1 µPa) from averaged power spectra (FFT analysis: spectral level units, Hann evaluation window, 50% overlap, FFT size 1024) recorded in standard stock tanks used for housing stickleback prior to studies (AS), ambient conditions in still freshwater test tanks (AT), and ambient conditions in an example freshwater lake in the UK (AL).
Mentions: Twenty-four adult three-spined sticklebacks were used as subjects, with an additional twelve individuals (familiar to the subjects) used as companion fish; presence of a ‘companion’ fish in proximity to the focal fish aids normal behaviour of the focal fish during testing (stickleback are housed in stable social groups). Fish were wild-caught in a UK river by a reputable biological supplier. Prior to experimental testing, fish were acclimated to the captive environment in the indoor fish facilities at the University of Bristol: groups of up to 20 sticklebacks were housed in 100 l stock tanks with an air sponge and external power filtration, at 10°C on a 12:12 light dark cycle (keeping the fish in non-breeding winter condition), and fish were fed three times per week on frozen bloodworm (Chironomid larvae). Care was taken to minimise the intrusion of artificial noise into the stock tanks, particularly with regard to frequencies below 2 kHz, which are in the possible hearing range of fish, such as the three-spined stickleback (see [35] for an audiogram of another Gasterosteidae, the nine-spined stickleback Pungitius pungitius), that have a swim bladder but no known hearing “specializations” [36]. Fish were housed in tanks placed on thick polystyrene boards in thermally insulated rooms, within a building separate from the associated University building (minimising the transmission of low-frequency external building noises); external power filters were placed on a separate base (minimising transmission of low-frequency filter noise); power filter outflows were piped underneath the water surface (minimising noisy disruption of the water surface); and sponge filter air flows were at low pressure (minimising low-frequency noise from filter vibration and high-frequency noise from air bubbles). The resulting ambient sound levels, at frequencies below 2 kHz, were slightly higher in standard pre-trial housing tanks than the ambient acoustic conditions in still freshwater test tanks (with no filtration or air flow; median difference of sound pressure level (SPL) in 43 Hz steps from 43–1938 Hz (spectral density, dB/Hz): 7 dB re 1 µPa; Figure 1) and an example freshwater lake habitat (median difference: 9 dB re 1 µPa; Figure 1), but comparable to freshwater streams and rivers reported in [37] that are typical of the habitat where the study species lives naturally.

Bottom Line: The addition of noise induced only mild fear-related behaviours--there was an increase in startle responses, but no change in the time spent freezing or hiding compared to a silent control--and thus had no significant impact on the total amount of food eaten.However, there was strong evidence that the addition of noise increased food-handling errors and reduced discrimination between food and non-food items, results that are consistent with a shift in attention.Consequently, noise resulted in decreased foraging efficiency, with more attacks needed to consume the same number of prey items.

View Article: PubMed Central - PubMed

Affiliation: School of Biological Sciences, University of Bristol, Bristol, United Kingdom. julia.purser@bristol.ac.uk

ABSTRACT
Acoustic noise is known to have a variety of detrimental effects on many animals, including humans, but surprisingly little is known about its impacts on foraging behaviour, despite the obvious potential consequences for survival and reproductive success. We therefore exposed captive three-spined sticklebacks (Gasterosteus aculeatus) to brief and prolonged noise to investigate how foraging performance is affected by the addition of acoustic noise to an otherwise quiet environment. The addition of noise induced only mild fear-related behaviours--there was an increase in startle responses, but no change in the time spent freezing or hiding compared to a silent control--and thus had no significant impact on the total amount of food eaten. However, there was strong evidence that the addition of noise increased food-handling errors and reduced discrimination between food and non-food items, results that are consistent with a shift in attention. Consequently, noise resulted in decreased foraging efficiency, with more attacks needed to consume the same number of prey items. Our results suggest that acoustic noise has the potential to influence a whole host of everyday activities through effects on attention, and that even very brief noise exposure can cause functionally significant impacts, emphasising the threat posed by ever-increasing levels of anthropogenic noise in the environment.

Show MeSH
Related in: MedlinePlus