Of the many ways in which humans have harmed marine life, one of the most serious is by pollution. About half of all new development in the U.S. occurs along the coast, and the pollution
from this development drains into the ocean (Human, 2002). Pollution comes in the form of sewage, toxic chemicals, pulp mill and manufacturing waste, fertilizers, soaps, detergents, radioactive wastes, plastics, oil spills, runoff, and insecticides.
Unregulated trawlers drag large heavy nets, chains and gear along the ocean floor, stripping it of its inhabitants and destroying whole ecosystems (Human, 2002). Bottom trawling is believed to have caused the decline of major fisheries because it destroys critical habitat for many species. Damaged coral can take centuries to grow back, and coral provides a home for thousands of underwater species.
Overfishing by factory ships from all over the world, which haul fish out of the sea in horrendous quantities, is destroying sea life by destroying food chains (Human, 2002). There has been a 90 percent decline in horseshoe crab numbers because of overfishing, and horseshoe crabs are critical in providing a food source (crab eggs) for shorebirds migrating from South America to the Arctic Circle.
Oil spills and leaks are destroying ocean life around the Galapagos Islands (Human, 2002). In January, 2001, almost 200,000 gallons of oil spilled from an oil tanker that ran aground and split open due to human misjudgement.
Lost and discarded fishing lines and nets cause wounds and suffocation to sea animals (Human, 2002). Driftnets have trapped whales, and cut them to the bone. Millions of dolphins have been drowned in fishing nets.
Human impact on oceans. (2004). Retrieved 8 October, 2004 from:
http://www.eco-pros.com/humanimpact.htm
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