Overexploitation
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Overexploitation

In a few words…
Overexploitation and abusive harvesting of species are at the heart of the threats that loom over biodiversity on our planet. Overhunting, overfishing, poaching, illegal species trafficking, exploitation of bushmeat and removal of species for purposes of entertainment (like certain aquarium fish) are examples of overexploitation that, by reducing a population, can, over time, strike a fatal blow to the affected species.

Overview of the situation
Overexploitation of species and natural environments poses a significant threat to biological diversity on our planet, and nothing currently indicates that this damaging practice is decreasing. Agreements to protect threatened species have been ratified in several countries, protected areas have been created, fishing practices and equipment have been changed, but still, numerous animal populations are still declining. Of course, these measures are absolutely necessary and they do help several species and ecosystems that would, otherwise, experience a much worse fate. They remain generally insufficient, however, and the decline of species continues to be observed, especially in tropical climates and freshwater environments.

As far as marine ecosystems are concerned, overexploitation has remained the main type of pressure exerted by humanity for decades. Between the early 1950’s and the mid-1990’s, the volume of fishing hauls in the world quadrupled! Afterwards, total hauls began to decrease, even in spite of increased fishing efforts, which indicated that many stocks did not have the ability to rebuild themselves.

The FAO estimates that over a quarter (28%) of saltwater fish stocks are overexploited, depleted (3%) or slowly rebuilding after depletion (1%) and that more than half (53%) of these same stocks are completely exploited. Only 15% of fish stocks worldwide are under-exploited or moderately exploited! Even if fishing authorities impose more realistic quotas for the size of the catch that can be safely removed from oceans, about 63% of the fish stocks evaluated all over the world need to be rehabilitated. Innovative fishery management approaches, such as inciting fishermen to help keep the stocks healthy, have proven useful in the places where they have been implemented.

Incidentally, bushmeat (or game) represents an important food source for several families living in the wooded areas of Central Africa, but the animals that provide it appear to be hunted beyond sustainable levels. In certain areas, this has contributed to what we term “empty forest syndrome” in which seemingly healthy forests become almost devoid of any animal life. This situation can have dire consequences for these forests, because approximately 75% of tropical trees depend on animals to disperse their seeds.

Another example: Cambodian freshwater snakes were overhunted to be sold to crocodile farms, restaurants and fashion professionals. Consequently, between 2000 and 2005, during the low season, catch in numbers, per hunter, have decreased by over 80%.

A large number of other wild species have also experienced decline due to overexploitation, from very well-known species such as tigers or turtles, to less familiar ones, such as Encephalartos brevifoliolatus, a type of small palm tree, now extinct in the wild due to its overexploitation for horticulture.

Examples of overexploitation – Overhunting – Overfishing – Abusive collection of wild specimens for entertainment purposes (like certain aquarium fish) – Poaching – Illegal trafficking of rare or threatened species – Exploitation of bushmeat (or game)

Did you know?
For over five centuries, the Atlantic cod, abundant in the North Atlantic, supported generations of families. In 1968, 800,000 tons of cod were fished out of the waters around Newfoundland! Then, the catch began to decrease and to yield increasingly younger and smaller specimens. Cod fishing was forbidden in 1992: the cod population a was experiencing a freefall. From one day to the next, thousands of fishermen were deprived of their livelihood. In spite of this measure, we estimate that the stocks of Atlantic cod are only about 1% of what they were 30 years ago.

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