Microplastics are a growing threat to all ecosystems, but particularly to marine life. Megafauna such as toothed and baleen whales face different threats regarding microplastics, but the impact remains the same. It is important to monitor these large creatures as they can act as not only ecosystem indicators, but also ecosystem regulators. A balanced environment needs the right amount of large predators to keep populations of the lower levels of the food chain in check. Too few apex predators can lead to overpopulated prey and potential depletion of resources, throwing the whole ecosystem out of whack. Monitoring the health of tertiary populations is crucial to ecosystem well-being, and as they do not reproduce as often as species at lower trophic levels, every individual is vitally important.
The toxins that leach out of plastic debris in the ocean pose a threat to all marine life. Studies have shown evidence of plastic contaminants not only in stomachs, but in tissues, skin, and other major organs of various aquatic species. Consumption of such species, and of plastic debris itself, causes these toxins and chemicals to travel up the food chain, accumulating in top predators and even ending up in humans. Aquatic megafauna are particularly at risk of a high toxin accumulation rate, which could lead to serious health issues, potentially including infertility, decreased immune health, and many other effects, all of which could lead to lower reproduction rates and therefore declining populations.
The very nature of microplastics makes them difficult to detect and nearly impossible to collect or remove from the ocean, leaving few options for mitigation. It is important that as much pollution be removed from the ocean as possible to prevent larger debris from breaking apart and eventually becoming microplastics, as well as to limit the amount of macroplastics, or large debris ingested by marine life. In addition, reducing single-use plastic production and consumption within human society as a whole will decrease the amount of debris that ends up in the ocean. By willfully decreasing demand for single-use plastic, less of it will be made, leaving less to end up in the oceans.