Overexploitation
Overexploitation refers to the unsustainable harvesting of renewable resources, leading to their decline to a point where they cannot recover within a generation. This phenomenon poses significant threats to biodiversity and ecosystems, with studies suggesting that it could contribute to a sixth mass extinction. Notable examples of overexploitation include commercial overfishing, deforestation, and overhunting of species like tigers and sharks.
In marine environments, practices such as large-scale commercial fishing have severely impacted fish populations, with 87% of oceanic fish stocks reported as overexploited. For instance, the Atlantic cod has experienced a dramatic population crash due to overfishing, raising concerns about its potential extinction. Similarly, land-based ecosystems face challenges from illegal poaching and habitat destruction, threatening species such as elephants and rhinoceroses.
Overexploitation disrupts food chains and ecological balances, leading to a ripple effect that can endanger multiple species and their habitats. Conservation efforts are crucial in addressing these issues and promoting sustainable practices to ensure the recovery of affected populations and ecosystems.
Overexploitation
Overexploitation is the process of harvesting a renewable resource to the point that the resource cannot recover within a generation. Environmental scientists and biologists have demonstrated that extended overexploitation can lead to the extinction of species and may cause irreparable damage to the environment. Commonly cited examples of overexploitation include modern commercial fishing, deforestation, overhunting, and the overharvesting of rare lumber for profit.
Overview
Overexploitation is a widespread problem in the modern world. Human overuse of natural resources significantly damages Earth's ecosystem. In fact, some researchers believe that humanity is directly pushing the planet toward a sixth mass extinction. Previous mass extinctions have occurred when environmental conditions changed too quickly for key parts of the food chain to adapt. When those key species die out, the rest of the food chain quickly follows the same path. However, while global warming is a distant threat with similar repercussions, humans are currently harvesting many of those key species well beyond sustainable amounts. Marine wildlife is a good example of this. In the last few decades, overexploitation of large ocean animals has driven several species to the brink of extinction and is threatening many others.
Commercial Overfishing
Commercial overfishing is the process of routinely harvesting more fish from the oceans than fish populations can reasonably sustain. In the early twentieth century, most people believed that the oceans were so vast that humanity's harvests could not affect the life that existed there. Over time, however, large-scale commercial fishing fleets developed. These fleets use sophisticated technology that allows them to drag giant nets along the ocean floor, capturing all life that exists there. This practice, coupled with lax regulation, has directly led to the crash of various fish populations around the world.
The Food and Agriculture Organization (FAO) reports that 87 percent of the world’s oceanic fish populations are either overexploited or fully exploited—which means that if additional fish are removed from the population within a breeding cycle, that population will not be able to recover. Experts predict that if world governments fail to take drastic action, all marine populations fished for food will completely collapse by the year 2048. For example, the once-plentiful Atlantic cod found off the coast of Alaska has collapsed from overfishing. The species is now critically endangered, with a population just one-tenth of 1 percent of its former size. Additionally, in the two decades scientists have studied this collapse, cod populations have failed to show any signs of recovery. Experts are unsure that the population will ever be able to do so. By 2024, Atlantic cod stocks had not substantially recovered. Experts believed that the species was trending towards commercial extinction.
Shark populations are a commonly cited example of oceanic overexploitation. Historically, sharks have suffered a bad reputation. Because of this, legislators have been reluctant to pass laws prohibiting or regulating the overfishing of sharks. However, overfishing has caused the shark population to drop 80 to 95 percent. In fact, in 2023, more than 73 million sharks are caught and processed annually for teir fins alone. These animals are particularly vulnerable to overfishing because they reproduce slowly, and offspring take many years to reach sexual maturity.
Some environmentalists claim that allowing major species of sharks to go extinct will lead to catastrophic results. By removing the top predator in a given food chain, the animals it keeps in check will reproduce more rapidly. The second animal will then eat its own source of prey to extinction, and then crash in population itself due to lack of food. The new top predator in the food chain will find itself with no natural predators, grow drastically in population, and a chain reaction will begin. This reaction could carry through the entire marine food chain.
Land-Based Overharvesting
Overexploitation endangers the world's forests and other biomes in the same way it does the world's oceans. Overzealous harvesting of trees and rare plants before they have reproduced has severely damaged the populations of many species. Hunters have nearly wiped out tigers and other big cats in the wild, and elephants, rhinoceroses, and other large “trophy” animals are in similar situations. Many Asian countries have a huge demand for the body parts of big cats, which are used in traditional medicinal recipes. International regulations have failed to stop the illegal hunting of these animals. Additionally, due to human encroachment on their territory, much of the habitat once occupied by these animals is gone. Overharvesting of trees and other plants has caused large chunks of forests to disappear, and overexploitation of bush animals has collapsed the food chains within much of what is left, leading to "empty forest syndrome," or forests that are structurally intact but devoid of animal life.
The global tiger population is a good example of the overexploitation of land-based ecosystems. Severe loss of habitat through commercial logging has devastated the habitats of tiger populations. Worse, the small surviving groups are similarly poached, primarily because their teeth, whiskers, bones, skins, tails, fur, and eyes are all common ingredients in traditional Chinese medicine. The decline in tiger populations has made these ingredients rarer, and thus much more valuable than they have been in the past. This encourages more hunting, which further reduces populations, which in turn raises the value of the ingredients in a vicious cycle that could end with the global extinction of tiger species. However, for the first time in decades, drastic conservation efforts have stabilized what little is left of the tiger population. By 2023, these conservation efforts had resulted in a 74% increase in wild tiger populations since 2010. Despite these critical gains, tigers remained an endangered species.
Tyler J. Biscontini
Bibliography
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Peres, Carlos A. "Overexploitation." Oxford University Press. 2014, www.conbio.org/images/content‗publications/Chapter6.pdf. Accessed 13 Jan. 2025.
"Tiger." World Wildlife Fund, 2023, www.worldwildlife.org/species/tiger#:~:text=By%202023%2C%20this%20effort%20proved,and%20monitoring%20of%20tiger%20populations. Accessed 13 Jan. 2025.