The Impact of Ocean Noise Pollution on Fish and Invertebrates Report for OceanCare, Switzerland, 2018, 36pp
Linda S. Weilgart
The report contains highly relevant information on the impact of ocean noise on prey species with consequences on whale welfare:
Most fish and invertebrates vitally depend on sound. Here, 115 studies of different anthropogenic underwater noise sources, 66 fish and 36 invertebrate species are reviewed. Noise impacts include body malformations, higher egg or immature mortality, delays in development, growth, metamorphosing, and settling. Zooplankton suffered high noise mortality. Noise caused massive internal injuries, cellular damage to statocysts and neurons causing disorientation and death, and hearing loss, even 96 hours post-exposure. Stress impacts were documented, including increased stress hormones, metabolic rate, oxygen uptake, cardiac output, parasites, irritation, distress, and mortality rate, e.g. from disease and cannibalism; and decreased body condition, growth, weight, consumption, immune response, and reproductive rates. DNA integrity and overall physiology were compromised. Animals showed alarm responses, increased aggression, hiding, and flight reactions; and decreased anti-predator defense, nest digging, nest care, courtship calls, spawning, egg clutches, and feeding. Noise caused more distraction, food-handling errors, and predation vulnerability, and decreased foraging efficiency, feeding, and schooling. Masking reduced communication quality and distance. Some commercial catches dropped substantially, with larger fish leaving. Increased bycatch rates and decreased fish abundance were observed. Key invertebrate ecological services, e.g. water filtration, mixing sediment layers, and bioirrigation, were impacted. When noise compromises population biology and ecology, fisheries and human food security are also affected. Turtles, sharks, and rays were underrepresented in noise impact studies. Research on marine animalsâ€™ survival, reproduction, population viability, and ecosystem function, is vital. Long-term, realistic noise field studies also considering cumulative and synergistic effects, along with stress indicators, are needed.