Impacts of noise pollution on marine wildlife

Introduction

Wildlife is diverse plants and animal species that occupy varieties of natural habitats. Globally, the number of wildlife is declining at a depressing rate. Noise from boats, ships, military sonar, underwater construction, and seismic surveys for oil and gas has interfered with the natural soundscape of the ocean. Many marine species rely on sound to transmit and communicate information; however, as human-induced ocean noise increases, it prevents them from navigating, communicating with each other, and identifying prey and predators. Underwater noise pollution, a widespread and unnoticed plague, negatively impacts aquatic animals.

 The effects of sea noise pollution vary among large sea creatures depending on the frequency, intensity, and duration. The impacts include behavioral changes, habitat displacement, and physiological stress.

This report will examine the impacts of human noise on marine species and recommend some solutions. 

1. Behaviour changes

Some animals experience behavioral change due to the presence of noise. Since oceanic species rely on sound for survival, underwater noise interferes with their ability to distinguish between their natural sound and noise. Response to masking occurs differently in sea animals: either increase the length of biologically significant tones or adapt to increase outside noise. For instance, a study showed that beluga whales vocalized more loudly when exposed to higher noise levels, a reaction called the Lombard Effect(Fletcher and Munson,1937).

2. Habitat Displacement

When animals underwater experience intense noise for a prolonged period, they often migrate from their habitats to somewhere with less noise. The sudden displacement from important habitats causes species to adapt to the new environment or go extinct. Moreover, removal from preferred habitats might have detrimental consequences like increased mortality.

3. Damage to tissues and organs

Marine species living in environments closer to high noise usually undergo trauma and injuries. The increased noise level damages animals hearing systems making it difficult to detect prey or avoid ships and barriers. Some hearing impairment has led to the deaths of sperm and humpback whales in industrial areas with boat traffic and fishing gear  (Lien et al. 1993).

Solutions 

• Increased awareness about the impacts of noise on aquatic animals should be encouraged. 

• Human activities should be restricted in biodiverse marine ecosystems and habitats.

1. Fletcher, H., & Munson, W. A. (1937). Relation between loudness and masking. The Journal of the Acoustical Society of America, 9(1), 78–78. https://doi.org/10.1121/1.1902030

2. Lien, J., Todd, S., Stevick, P., Marques, F. and Ketten, D. 1993. The reaction of humpback whales to underwater

explosions: movements and behavior. Journal of the Acoustical Society of America 94: 1849.