1. The Impact of Human-Caused Ocean Noise Pollution on Fish, Invertebrates, and Ecosystem Services
Lindy Weilgart, Ph.D.
OceanCare, Switzerland
&
Department of Biology Dalhousie University Halifax, Nova Scotia CANADA

2. Sound in the Water Speed of sound in seawater is about 5x that in air
Sound on land extends 1-10 kilometers
Sound can travel 1,000s of kilometers underwater very fast

3. Humans use Sight, Marine Animals use Sound
Marine animals “see” with their ears. To marine animals, flooding the ocean with noise is like shining a flashlight into our eyes, blinding us.

4. Marine animals rely on sound for all life functions
Depend on sound for:
Food-finding
Reproducing
Communicating
Avoiding predators and hazards
Navigating
Sensing their environment

5. Impacts of Noise on Marine Animals
Most marine animals use sound for vital functions
102+ fish and invertebrate species impacted by noise
66 species of fish
36 species of invertebrates
Recently, studies on fish and invertebrates show impacts extend beyond individual species to include communities of species and how they interact, compromising ecosystem productivity, and ecological services (sediment mixing, nutrient cycling), with commercial consequences

6. Sources of Noise
Shipping
Seismic Airgun Survey

7. Seismic Airguns For detecting oil and gas under sea floor
Loud, intense, broadband impulses or “shots” from air released under very high pressure
High acoustic peak pressure (263 dB) and sharp (short) rise time
Arrays of airguns
Ocean floor penetration > 100 km even after going through sometimes 1,000s of m of water
Every 10 s, 24 hrs/day, usually over months
Powerful enough to take your arm off if fired at close range
Seismic Airguns

8. 3D Seismic: Bird’s-Eye View
Sea surface area covered by towed seismic array = 26 km2
Source: PGS

9. Off N.S., 3 surveys at any one time over summer
Moored hydrophones
along Mid-Atlantic Ridge:
Seismic airgun noise off Nova Scotia formed the main part of background noise 4,000 km away.
Seismic airgun noise heard nearly constantly throughout Atlantic based on a decade of sea floor monitoring.
Off N.S., 3 surveys at any one time over summer
(Nieukirk et al. 2012) cc
Nova Scotia
Mid-Atlantic Ridge cc cc cc cc

10. Global Offshore Seismic Exploration (1994-2005)
Courtesy of John Hildebrand

11. Loudness of Various SoundsdB
Seismic array dB
Single air gun
255 dB
Undersea
earthquake
260 dB
Undersea volcano
267 dB
0.5 kg TNT
Decibel scale is logarithmic--
each increase in 3 dB is a doubling of intensity

12. Impacts of Noise on Marine Animals
Development
Body malformations
Higher egg or immature mortality
Developmental delays
Delays in metamorphosing and settling
Slower growth rates
Anatomy
Hearing loss (up to months or permanent)
Cellular damage to statocysts/neurons
Massive internal injuries
Disorientation and death

13. Impacts of Noise on Marine Animals
Physiology (stress)
Worse/lower:
Increases in:
Body condition
Stress hormones
Growth
Metabolic rate
Weight
Oxygen uptake
Food consumption
Cardiac output
Immune response
Parasites
Reproductive rates
Irritation
DNA integrity
Distress
Overall physiology
Mortality rate (disease and cannibalism)

14. Impacts of Noise on Marine Animals
Behavior
Avoidance of important habitat, days to years
Alarm responses, hiding, flight
Increased aggression
Decreased anti-predator defense
Decreased nest-digging and care
Decreased courtship calls, spawning, egg clutches
Decreased feeding
Distraction (food-handling errors, inefficiency)
Uncoordinated schooling

15. Impacts of Noise on Marine Animals
Masking (obscuring, obliterating of sounds of interest)
Commercial catch rates
Decreased landings
Large fish leave area
Increased bycatch
Decreased abundance
Ecological Services
Less water filtration
Less sediment layer mixing
Less bio-irrigation (key to nutrient cycling)

16. Seismic Airgun Noise Kills Zooplankton
Single airgun causes “hole” in zooplankton out to 1.2 km (max range examined) (McCauley et al. 2017)
Most seismic surveys consist of airguns
Numbers halved in most plankton species
1/3 of species almost entirely killed
All krill larvae killed
2-3x more dead zooplankton
Healthy populations of fish are not possible without viable planktonic productivity
From McCauley et al. 2017

17. Noise Impacts on Ecosystem and Ecological Services
Pile driving noise caused valve closure in mussels, energetically costly behavior, disrupting breathing, heart rate and excretion, halving oxygen concentrations and doubling CO2 levels in 3 hrs (Roberts et al. 2015)
Growth and body condition likely to suffer, with ecosystem and commercial consequences

18. Noise Impacts on Ecosystem and Ecological Services
Ship noise suppressed oyster activity and volume of water flowing over their gills, decreasing food uptake, causing slower fat metabolism and growth rate, greater oxidative stress (Charifi et al. 2018)
The slowdown in growth constitutes “a potentially massive risk in terms of ecosystem productivity”

19. Noise Impacts on Ecosystem and Ecological Services
Boat noise increased larval mortality and developmental failure in sea hare embryos (Nedelec et al. 2014)
Keep corals and algae in balance, graze on toxic bacteria
Ship generator noise increases mussel biofouling but decreases size with “potential cascading ecological impacts” (Jolivet et al. 2016)
Vessel hull fouling responsible for 75% of invasive species brought in by ships (McDonald et al. 2014)
Costs U.S. Navy US$1 billion every year
Noise causes confusion and disrupts orientation behavior at a critical (larval) stage in reef fish (Simpson et al. 2010)
Could affect population welfare, weaken connectivity between populations, reducing replenishment of fished species

20. Noise Impacts on Ecosystem and Ecological Services
Noise repressed burying and bio-irrigation behavior (or water circulation within lobster burrows) in Norway lobsters (Solan et al )
Manila clams showed a stress response to noise, individuals relocated less, stayed on top of the seabed, and closed their valves, increasing lactate dangerously
Clams could not mix upper layers of sediment and could not feed
Noise changed the fluid and particle transport that invertebrates provide, key to nutrient cycling on the seabed

21. Noise Impacts on Ecosystem and Ecological Services
A seismic survey caused reef fish abundance to decline by 78% in the evening when fish habitat use was highest (Paxton et al. 2017)
Such reactions of an entire community of species means fish lose opportunities to aggregate, forage, or mate
Response occurred across fish species
Temperate coral reef 1 day before seismic
Same reef with seismic 8 km away
From Paxton et al. 2017

22. Impacts of Noise on Invertebrates
Shrimp in louder tanks exhibited stress, decreased growth, food consumption, reproductive rates (50% vs. 80%), egg-bearing females (70% vs. 92%), increased mortality (from disease and cannibalism) (Lagardère 1982), and metabolism (higher oxygen consumption and ammonia excretion) (Régnault & Lagardère 1983)
Seismic airgun noise caused chronic impairment of immune competency and nutritional condition in lobsters up to 120 days post-exposure (Fitzgibbon et al. 2017).
Developmental delays from seismic in scallop larvae in tanks; 46% with body malformations (Aguilar de Soto et al. 2013)
Types of impacts

23. Seismic significantly increased mortality in scallops
Mortality continued to increase over time
Day et al.2017

24. Noise Impacts on Ecosystem and Ecological Services
6 hrs of ship noise caused breaks in DNA of blue mussel, lower filtration (algal clearance), oxidative stress (Wale et al )
Mussels could not perform important ecological service of water filtration
Scallop mortality increased with seismic survey, reflexes disrupted, immunocompromised, imbalanced electrolytes (Day et al. 2017)
Scallops improve water quality through bio-filtration, increase light for underwater plants, decrease eutrophication, feed bottom-dwelling organisms by depositing organic matter from water column
Predator-prey interactions in fish changed with boat noise (Sabet et al. 2015; Simpson et al. 2016)
Food web dynamics, community structure and stability compromised

25. Noise Impacts on Invertebrates & Fish
LF noise caused substantial, permanent, cellular damage to statocysts and neurons in squid, cuttlefish, octopus, jellyfish (André et al. 2011; Solé et al. 2013a, 2013b, 2016, 2017)
“…massive acoustic trauma, not compatible with life…” (André et al. 2011)
Extensively damaged caged snapper fish ears in the field from seismic noise. No recovery after 58 days (McCauley et al. 2003). Snapper ear is similar to tuna ear.
After
Before
McCauley et al. 2003

26. Impacts of Noise on Invertebrates & Fish
Increased stress hormones and indicators in bass, sea bream, cod, carp, perch, gudgeon, kelpfish, goldfish, shrimp, crabs, mussels, scallops, lobsters, sea horses (Bruintjes et al. 2017; Buscaino et al. 2010; Celi et al. 2016; Day et al. 2017; Filiciotto et al. 2016; Fitzgibbon et al. 2017; Graham and Cooke 2008; Lagardère 1982; Nichols et al. 2015; Régnault & Lagardère 1983; Santulli et al. 1999; Sierra-Flores et al. 2015; Smith et al. 2004; Spiga et al. 2016; Wale et al. 2013; Wale et al. 2016; Wysocki et al. 2006)
Cortisol increased 81%-120% in fish species with shipping noise playback (Wysocki et al. 2006)
Types of impacts

27. Impacts of Noise on Fish
Sea bream moved more, showed stress and intense metabolic activity, with less energy for feeding, migration, reproduction with vessel noise (Buscaino et al. 2010; Celi et al. 2016)
Sea bream increased their oxygen uptake, implying higher stress levels, with pile driving noise (Bruintjes et al. 2017).
Types of impacts

28. Impacts of Noise on Fish (cont’d.)
Tuna schooling lost aggregated structure, became uncoordinated, aggressive, with vessel noise
Can affect homing accuracy of migration to spawning and feeding grounds (Sara et al. 2007).
Long-term abundance of blue whiting and other mesopelagic fish higher outside seismic shooting area than inside, deeper (Slotte et al. 2004).
Fish in MPA responded to boat noise as to predator attack (La Manna et al. 2016), decreased nest-caring (Picciulin et al. 2010), feeding (Bracciali et al. 2012), and ability to defend territory (Sebastianutto et al. 2011), caused masking (Codarin et al. 2009) and more calling (Picciulin et al. 2012).
Types of impacts

29. Noise Reduces Catch and Abundance of Commercially Important Fish
5 days after seismic:
Commercial trawl cod catch↓69%
Longline cod catch ↓45%
Longline haddock catch ↓67%
↓ 52% in CPUE for rockfish hook-and-line fishery
50% average economic loss
Trawl catch rates of cod (A) & haddock (B) B (solid), D (striped), A (gray) seismic, by distance (nm) from seismic
Total quantity of cod and haddock by mass B (solid), D (striped), A (gray) seismic
Engås et al. (1996), Skalski et al. 1992

30. Hassel et al. 2004

31. Before During After In seismic shooting area (5.5x18.5 km):
Trawl catches
of haddock and cod
and longline of
haddock
reduced by 70%
Fish abundance,
catch rates
didn’t return to
pre-seismic levels
5 days after
seismic shooting
stopped
Before
During
5500 sq. km represented
After
Engås et al. 1996

32. Summary Most marine fauna very dependent on sound
102+ fish and invertebrate species shown to be impacted
Impacts include decreased growth, body condition, feeding, reproduction, abundance, immune competency, nutritional condition, catch rates, school coordination and structure, nest-caring, territory defense.
Noise caused permanently damaged ears and sensory organs, developmental delays and malformations, and increased stress, metabolism, masking, and mortality
Impacts extend beyond individual species to include communities of species and how they interact, compromising ecosystem productivity, and ecological services (sediment mixing, nutrient cycling) with commercial consequences