Download - Effect of anthropogenic noise
Ilaria Spiga1, Joe Fox1, Robert Benson1, Addison Lawrence2, and David McKee1 1 Texas A&M‐Corpus Christi, Corpus Christi, USA.
2 AgriLife Research Mariculture Laboratory, Port Aransas, USA
Introduc)on Increases in human activity in the aquatic environment have substantially increased background noise in the past 50 years (Ross, 1973)
likely to increase further (NRC, 2003)
All motor‐driven boats, regardless of design, contribute to ambient underwater noise
frequencies and levels directly related to their size (Richardson et al., 1995)
In coastal waters, small vessels such as fishing and recreational boats (high speed engines) are more common
They add high frequency, broadband sounds to the background noise (Richardson et al., 1995)
Importance of Sound Sound propagates much farther and faster underwater than in air Underwater sound allows marine animals to gather information and communicate at great distances and from all directions (Richardson et al., 1995)
Marine animals rely on sound to acoustically sense their surroundings communicate locate food and protect themselves underwater (Popper et al., 2004)
Research to date
Depending upon the magnitude of the signal:
No impact on animals (Popper et al., 2007)
Disruption of behavior (Vabo et al., 2002)
Physiological damage (Popper et al., 2004; Smith et al., 2004)
Feeding behavior and survival (Wysocki et al., 2007; Davidson et al., 2009)
Ra)onale for research Responses are diverse and species‐related
More information is necessary
Increase in number of recreational boats in Texas since 2006 (NMMA, 2008)
Increase in recreational fishing activity in Texas bays and estuaries (Tseng et al., 2006)
Can noise affect growth and survival in red drum and spotted sea trout during their early life history?
Objec)ves
To determine the effect of boat noise on growth, survival, and condition factor on juvenile red drum and spotted seatrout
To evaluate by observation, potential of fish to acclimate to anthropogenic noise
Fish targeted Sciaenids: drums and croakers
Red drum and spotted seatrout
Juvenile red drum (0.35 g ± 0.01) and spotted seatrout 0.32 ± 0.01) provided by Texas Parks and Wildlife CCA/CPL Marine Development Center (Corpus Christi, TX, USA)
Research site and system
Research conducted at Texas AgriLife Research Mariculture Laboratory, Port Aransas, Texas, USA
Semi‐closed recirculating aquaculture system (RAS) containing biofiltration and artificial aeration
Experimental System and Design System 3 cylindrical tanks (5‐m diameter) per species
3 treatments: 1. Background noise
(control) 2. Continuous noise 3. Intermittent noise
Stocking density 600 fish/tank
Completely randomized design
Fish exposed to noise for 8 wks
Acous)cs Sound treatments
Noise recorded from TCOON station in Corpus Christi Bay
Acquisition via hydrophone located near the bottom (1.5 m depth)
Recording made of approaching vessel passing about 20 m from the recording point (hydrophone)
Dual channel digital sound file structure: 1. Right channel carried
continuous sound 2. Left intermittent (30 min on,
30 min off) 50 sec long, highest amplitude 140 dB, 3 kHz.
Experimental protocol Dead fish removed daily Fish harvested after 8 wk of noise exposure
50 fish per subsample Growth determined as mean final wet weight (g) and mean final total length (cm)
Mean final condition factor/tank/treatment
Sta)s)cal analysis One‐way ANOVA by species of mean final wet weight (g), mean final Total length (cm), condition factor, and survival. Level of replication: one tank per species/treatment combination
Tukey's HSD test
One‐way block ANOVA with ranks of frequency distributions for each dependent variable by treatment, within species.
Tukey’s HSD test
Results: growth variables following 8 wk
Red drum Spotted seatrout
Dependent Variables
Background noise
Continuous noise
Intermittent noise
Weight (g) 10.1±1.8 9.5±3.9 11.5±6.4
Total length (cm) 8.4±1.6 1.0±1.6 10.4±1.4
Mean Specific
growth rate (%/day)
6.1 6.1 5.9
Condition factor 1.3±1.1 0.9±0.1 0.9±0.1
Survival (%) 33.2 27 26.8
Dependent Variables
Background noise
Continuous noise
Intermittent noise
Weight (g) 10.5±3.2 11.5±5.5 10.9±3.6
Total length (cm) 11.0±1.0 11.4±2.2 11.1±1.1
Mean Specific
growth rate (%/day)
6.50 6.47 6.49
Condition factor 0.77±0.08 0.8±0.07 0.78±0.07
Survival (%) 22 24.8 26
Results: final total length and final wet weight No significant difference No significant difference
Mean fin
al w
et w
eigh
t (g)
Mean fin
al w
et w
eigh
t (g)
Mean fin
al to
tal len
gth (cm)
Mean fin
al to
tal len
gth (cm)
Results: final wet weight distribu)ons Red drum: no significant differences Spotted seatrout: no significant differences
Wet
wei
ght f
requ
ency
W
et w
eigh
t fre
quen
cy
Wet
wei
ght f
requ
ency
Wet weight frequ
ency
Wet weight frequ
ency
Wet weight frequ
ency
Results: condi)on factor
c.f.= weight *100/L3
No significant differences (α= 0.05)
Mean fin
al con
dition
factor
Mean fin
al con
dition
factor
Results: condi)on factor frequency distribu)ons Red drum: no significant differences Spotted seatrout: no significant differences
freq
uency
freq
uency
freq
uency
freq
uency
freq
uency
freq
uency
range range
Red drum and spotted seatrout in the current study acclimated to the increased sound
Potentially, decrease immune efficiency and disease in the presence of additional environmental stressors, such as poor water quality, habitat losses, and predators. Therefore, noise should be considered as anthropogenic variable co‐affecting the eco‐physiology of these 2 species.
Effects of noise on fish are related to hearing sensitivity
Red drum and spotted seatrout are considered “hearing generalist” (100 ‐ 2000 Hz)
Broadband, high frequency noise from recreational fishing boats in estuaries may mask vocalizations and impair communication
Discussion: from the tank into the wild
Discussion: from the tank into the wild
Subtle responses found in Wysocki et. al (2007) and Davidson et. al (2009): Rainbow trout (hearing generalist) reacted to long‐term exposure to noise by slowing growth rate during the first month
In estuary noise from recreational fishing boats does not have a regular pattern as in the experimental study
Chronic noise exposure from recreational fishing boats might slow growth and, therefore, delay sexual maturation impairing reproduction of red drum and spotted seatrout while in the estuaries
Future Research Topics Use of trials to determine subtle responses during the early exposure to noise
Identification of the time in which adaptation to increased noise occurs
Multiple stressors (noise, T, pH, Ox) to determine responses that might happen into the wild
Otoliths to determine variation of growth
Conclusions There was no long term effect of noise exposure on red drum and spotted seatrout growth Juvenile red drum and spotted seatrout were successful in physiological adaptation to noise‐induced stress as evidenced by levels of dependent variable shown following the 8‐wk study
Behavioral observations: initial response to noise (either continuous or intermittent) shown by both species as swimming in tight circles around the center of the holding tanks
Adaptation was quite rapid Can adapt to pattern of noise as well (intermittent noise)
Acknowledgements AgriLife Research Mariculture Laboratory
Texas Parks and Wildlife
Harte Research Institute for Gulf of Mexico Studies
Drs. Joe Fox, Robert Benson, Addison Lawrence, and David McKee
Nico Amalfitano, Shane Merryman, Adrian Bandolon, and Leslie Adams