Water pollution causes immense damage to marine life and the death of numerous land animals. It kills more than a million mammals and seabirds every year and has caused around 400 dead zones worldwide.
Human activities are the main culprits of water pollution. Approximately 10 percent of the 100 million tons of plastic manufactured each year becomes ocean litter. Common sources of ocean litter include trash from cities, waste from landfills and containers accidentally thrown off into the sea during typhoons. All of these gather in large chunks, go with currents and end up washing ashore. Many marine mammals, fish and birds ingest the litter and suffer fatal consequences. The Trash Vortex of the North Pacific ocean has countless pieces of decaying plastic that create an enormous revolving garbage patch comparable to the size of Texas.
Farms that use excessive pesticides and fertilizers produce chemical runoff that leaches into groundwater, waterways and streams and kills thousands of fish and insects. The chemicals also change nutrient systems and cause the uncontrolled growth of algae that generate toxins and use up oxygen in the water, thus killing marine life.
Cruise ships throw 250,000 gallons of wastewater and sewage on a daily basis, resulting in massive destruction of aquatic life. The waste typically contains harmful bacteria, pathogens, oils and other dangerous substances that endanger most marine animals.