Fish and the Ocean
The oceans occupy over 70% of Earth’s surface area and over 90% of the biosphere’s volume. In terms of number of species and individuals, fishes far outnumber all other vertebrate classes (amphibians, reptiles, birds and mammals). Usually considered in terms of fisheries and food rather than as wildlife, it is only in the last 15 years that scientists have begun to assess the conservation status of fish in the same way as terrestrial vertebrates.
Threats
Some major problems for our oceans:
- Overfishing - depletes stocks of fish beyond their ability to recover. This disrupts the ecosystem and eliminates a valuable source of food and income.
- Destructive Fishing - can have very damaging effects on a range of ocean habitats.
- Climate Change - warming the oceans and making them more acidic. This is creating dead zones as plankton and corals, the primary producers for nearly all marine life, struggle to survive under inhospitable conditions.
- Pollution - poisons marine life and decimate entire marine environments. Vast quantities of solid and chemical waste from human activities are continually dumped and leach into the oceans, including plastics, sewage, oil and toxins that accumulate in food webs.
- Habitat Destruction - physically limits the suitable living space available to marine life.
Solution: Sustainable Fishing
With over 75% of world fish stocks fully or over-exploited, we are depleting the fish and other marine life that we eat faster than their populations can replenish. Sustainable fisheries aim to help ensure that a wild, diverse and healthy
ocean ecosystem will exist long into the future. This means fishing (or farming fish) in a way which allows fish stocks be harvested without compromising the ability of the population to replenish itself and without harming the environment. More on Sustainable Fishing
Fish Facts
Since 1500AD there have been 58 species documented to be extinct according to the IUCN Red List of Threatened Species.
We still know more about the surface of the moon than the bottom of the oceans. The proportion of undiscovered species may still be close to 70%–80% of all marine species.
Fish is the world’s main source of wild protein in our diets - fish provide more than 2.9 billion people with at least 15% of their protein.
Most Threatened
The most threatened marine species currently include:
- Seahorses -
find out what ZSL is doing to help seahorses through Project Seahorse .
- Tuna - read of the conservation of Bluefin Tuna here
- Whales - read about whale hunting and other impacts on declining whale numbers here
The Fishing Industry
Marine capture fisheries have exceptional value as a source of food, livelihoods and income for millions of people across the globe. Nearly 44 million people are engaged in the primary production of fish worldwide. Annual global fish trade is worth $92 billion, while the entire seafood industry is valued at $200 billion. More on the Fishing Industry
Solution: Marine Reserves
A marine protected area (MPA) is an area of the sea which is protected from harmful human activities. MPAs are a way of protecting endangered species and fragile habitats in the ocean. While around 10% of the World’s land surface is currently protected through national parks, this only applies to less than 1% of our oceans. More on Marine Reserves
