Forståelse av støyforurensning i havet

Støyforurensning i havet betyr at skadelig, menneskeskapt støy slippes ut i det marine miljøet. Dette omfatter støy fra seismiske luftkanonsprengninger (brukt til olje- og gassleting), skip og båter, militære øvelser og sonar, offshore-bygging og -industri, havnebygging, mudring og eksplosjoner. Disse lydene, særlig i de lave frekvensområdene, kan bevege seg hundrevis eller til og med tusenvis av kilometer under vann og forstyrre økosystemer langt fra kilden.

I motsetning til oss er mange marine arter i stor grad avhengige av lyd, ikke syn, for å tolke omgivelsene sine. Lyd er deres viktigste verktøy for kommunikasjon, navigering, matleting og for å unngå rovdyr. Når menneskelige aktiviteter overdøver eller forstyrrer disse akustiske signalene, kan det få alvorlige konsekvenser for livet i havet.

I løpet av de siste 50 årene har støynivået i havet økt 20 ganger!

Seismiske luftkanoner som brukes til oljeleting, avgir for eksempel lydimpulser som ofte avfyres med noen sekunders mellomrom i flere dager eller uker i strekk. 

Seismiske undersøkelser utenfor Vestfjorden, som hadde pågått siden 2012, foregikk fortsatt i 2024!

Militære sonarsystemer og propelldrevne fartøy bidrar også i betydelig grad til støynivået under vann, og noen av dem avgir kontinuerlig støy. Dette samlede lydbildet gjør havet stadig mer ugjestmildt for akustisk følsomme arter.

Biologiske konsekvenser for det marine livet

Det er påvist at langvarig støyeksponering forårsaker atferdsforstyrrelser hos marine dyr. For mange hvaler, delfiner og niser kan denne akustiske forstyrrelsen føre til:

• Midlertidig eller varig hørselstap
• Økte nivåer av stresshormoner
• Disruption of feeding, mating, and migration behaviors
• Abandonment of critical habitats

In severe cases, intense sound exposure has been linked to strandings and mortality. Beaked whales, for instance, are particularly vulnerable to mid-frequency active sonar and have experienced mass strandings following naval exercises.  

In 2016 we had a Sowerby’s beaked whale strand while seismic activity was occurring. See the  story of the Sowerby’s whale.

Humpback whales with impaired hearing may be less able to detect fishing gear, increasing the risk of entanglement.

These disruptions can affect not just individuals but entire populations, particularly those already under pressure from other threats such as climate change, overfishing, and habitat loss.

Long Term Consequences for Ecosystems

Ocean noise pollution doesn’t affect only marine mammals. Research has shown impacts on fish, invertebrates, and even planktonic organisms.  

Seismic air guns can kill plankton up to 1.2 km away from the source!

Species that use sound for mating, predator detection, or habitat selection may experience reduced reproductive success or increased mortality. In some regions, elevated noise levels have been associated with changes in community structure and ecosystem dynamics.

What Can Be Done

While ocean noise pollution is a global problem, solutions are both possible and increasingly urgent. Technologies such as quieter ship propellers and time area restrictions on noisy activities can significantly reduce acoustic impacts. Slowing vessel speeds has also proven effective, lowering both noise emissions and the risk of vessel strikes on whales.

Public awareness and informed consumer choices also play a key role. Reducing fossil fuel consumption, supporting local goods to decrease shipping demand, and choosing conscious businesses for tourism and other products can help reduce noise. Advocating for noise reduction policies, marine protected areas, and further research on ocean acoustics can help support change.

Conclusion

Anthropogenic noise is now recognized as a serious pollutant in marine environments. Underwater sound from ships, seismic surveys, and industrial activity interferes with how marine animals communicate, navigate, forage, and reproduce. As this noise increases, so do the risks to species that rely on sound to survive. We have the opportunity, and the responsibility, to protect the ocean’s natural acoustic environment.

Our project,  Havet av lyder, raises awareness of ocean noise pollution by turning research into experience. Through virtual reality, participants step into the perspective of an orca and encounter underwater noise firsthand, an immersive experience that builds empathy and understanding. An educational workshop introduces local marine mammals, their vocalizations, and the impact of ocean noise on their survival, along with actions we can take. It concludes with a lively quiz game and group discussion to reinforce learning and reflection. The Whale Exhibition showcases photographs, species information, and their sound recordings. A main part is the rare Sowerby’s beaked whale skeleton, with its local stranding story that occurred during seismic activity, showing the harm ocean noise can create. By connecting scientific evidence with public engagement,  Havet av lyder  encourages meaningful dialogue and inspires action toward a quieter, healthier ocean.

But awareness is only the beginning. Each of us has a role to play in creating a quieter ocean. By making informed choices in how we travel, what we buy, which companies we support, and how we vote, we help shape a healthier future for the sea. Together, we can reduce harmful underwater noise and ensure that marine life has the acoustic space it needs to survive, communicate, and thrive.

By: Ellyne Hamran