The Effects of underwater noise on sharks dolphins and whales
Introduction
Underwater noise is a kind of noise pollution mainly caused by human activities. Over the past decades, activities such as seismic exploration, leisure boating, shipping, offshore wind farms, and sonar maneuvers have been rising along the coasts and deep oceanic waters. These activities emit noises that can move for long distances under the water, given that sound moves five times more in water than in air. Sound is significant to sharks, dolphins, and whales, as it is among their primary survival tools. As discussed in this paper, short and long-term exposure to underwater noise pollution poses various marine life risks.
One of the significant consequences of underwater noise pollution is internal damages and stranding (being driven ashore) of dolphins and whales. Stranding often occurs after sonar maneuvers, an underwater communication technique that emits powerful sound. The excessive sound causes vascular damage to the marine species organs such as the brain and lungs (Parsons, 2017). Besides, the noise may cause the marine animal to panic and move quickly to the surface leading to the formation of nitrogen bubbles in their blood (referred to as the decompression illness) and death. Dead Sea creatures sink or are washed ashore.
Underwater noise pollution threatens sharks, dolphins, and whales’ population numbers. Increased noises hinder the marine species’ ability to locate prey for their food, which may be disastrous. Besides, more noise could lead to diminished prey species. Prolonged lack of food may cause behavior change as the species to turn hostile to creatures around them due to anxiety. Moreover, high underwater noise may affect marine animals’ reproductive success as it covers biologically valuable sounds (Erbe, 2012). Failing to locate potential mate during the mating seasons leads to reduced reproduction levels and decreased species population. Increased noises also hinder practical nursing, exposing the young ones to more dangers.
According to Rako-Gospić & Picciulin (2019), prolonged exposure to high noise levels may cause physical and psychological damage. As in humans, high noise levels are harmful to any living thing and may lead to temporary or permanent hearing loss. Loss of hearing can be devastating to these marine animals because it may entirely disrupt their ability to carry out essential survival functions, including feeding, breeding, communication, and evading vessel traffic. Furthermore, increased noise triggers stress and weakens the sea creature’s immune system making them vulnerable to ill health.
Increased underwater noise levels may lead to reduced communication (Erbe, 2012). Sharks, dolphins, and whales relate and find their way using their sense of hearing. Underwater sounds enable these sea creatures to pick and comprehend occurrences around them. Higher noise levels may lead to underwater disorder and aggressive behaviors. Higher noise levels may further hinder communication between marine animals trying to warn their mates of incoming danger. Poor contact may lead to reduced ability in defending their territories and resources from invaders.
Finally, increased noise may compel these marine species to flee from valuable habitat. The majority of sharks, whales, and dolphins inhabit the deep sea, away from human presence noises. More noise causes sea animals to escape and forsake their preferred environments to ensure survival (Rako-Gospić & Picciulin, 2019). Besides, these creatures could relocate while trying to follow their escaping prey. Relocation may negatively affect the animal’s ways of finding food, breeding, and nursing the young.
Conclusion
The effects of underwater noise on sharks, dolphins, and whales may be severe and immediate or may build up over the years. With the increasing population levels and emerging technology worldwide, human-caused underwater noise pollution will continue to rise. The sharks, dolphins, and whales’ survival is at risk. Therefore, marine life conservation is a universal issue requiring more intervention strategies to curb the impending catastrophe.
References
Parsons, E. C. M. (2017). Impacts of Navy Sonar on Whales and Dolphins: Now beyond a Smoking Gun?. Frontiers in Marine Science, 4, 295.
Erbe, C. (2012). Effects of underwater noise on marine mammals. The effects of noise on aquatic life (pp. 17-22). Springer, New York, NY.
Rako-Gospić, N., & Picciulin, M. (2019). Underwater noise: Sources and effects on marine life. In World Seas: An Environmental Evaluation (pp. 367-389). Academic Press.