Overharvesting
Overharvesting is defined as the excessive fishing of aquatic animals that include fish and shellfish. Overharvesting, or overfishing in the case of fish and marine invertebrates, depletes some species to very low numbers and drives others to extinction. In practical terms, it reduces valuable living resources to such low levels that their exploitation is no longer sustainable.
Ocean overfishing is simply the taking of wildlife from the sea at rates too high for fished species to replace themselves. The earliest overfishing occurred in the early 1800s when humans, seeking blubber for lamp oil, decimated the whale population. Some fish that we eat, including Atlantic cod and herring and California's sardines, were also harvested to the brink of extinction by the mid-1900s.
When did it start?
In the mid-20th century, international efforts to increase the availability and affordability of protein-rich foods led to joint government efforts to increase fishing capacity. But by 1989, when about 90 million tons (metric tons) of catch were taken from the ocean, the industry had hit its high-water mark, and yields have declined ever since.
When will it end?
Faced with the collapse of large-fish populations, commercial fleets are going deeper in the ocean and farther down the food chain for viable catches. This is triggering a chain reaction that is upsetting the ancient and delicate balance of the sea's biologic system. A study of catch data published in 2006 in the journal Science grimly predicted that if fishing rates continue apace, all the world's fisheries will have collapsed by the year 2048.
What's next?
Over the past 55 years, as fisheries have returned lower and lower yields, humans have begun to understand that the oceans we'd assumed were unendingly vast and rich are in fact highly vulnerable and sensitive. Add overfishing to pollution, climate change, habitat destruction, and acidification, and a picture of a system in crisis emerges. There is still hope, but illegal fishing and unsustainable harvesting still plagues the industry. A public grown accustomed to abundant seafood and largely apathetic about the plight of the oceans complicates efforts to repair the damage we've done.
Causes of overharvesting:
Positive effects of overharvesting:
- Commerce
- Lack of Government Regulation
- Technology
- Leads to the extinction of wildlife
- Over fishing also affects the structure of food webs and food chains
Positive effects of overharvesting:
- It keeps the price of fish way down.
- The capturing of fish has gotten easier of the years thanks to technology