What Is Overexploitation and How Does It Affect Biodiversity?

Understanding Overexploitation

Overexploitation, the unrelenting depletion of species, threatens thousands with extinction. Learn how this dangerous practice affects our ecosystems. Plants and animals are regularly exploited for building materials, the fur trade, exotic pets, and food. To do better, we must advocate for stronger domestic and international policies with adequate enforcement.  

Exploring Biodiversity

Biodiversity , the intricate web of life, is vital for a thriving planet. Discover its significance and our role in preserving it. At Defenders of Wildlife, we believe it’s crucial to conserve the close ecological relationship that benefits all life. This is why we are devoted to the protection of all native animals and plants in their natural communities. 

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Joe Quinn / Alamy Stock Photo

Impacts of Overexploitation on Biodiversity

The overhunting or overharvesting of species has exacerbated these once healthy populations into or near extinction. Some examples of overexploitation are: 

• Industrialized fishing  

• Animals hunted for trade or sport 

• Animals sold into the pet trade  

• Logging mature natural forests 

• Excessive plant harvest (e.g., ginseng, orchids, cacti and succulents) 

Restoring Balance: A Case Study

Species' populations can also be negatively impacted by the unsustainable overextraction of natural resources. Though not the intended target, wildlife is often vulnerable to fossil fuel and mineral extraction. For example the Willow Project, which Defenders fought to stop, aims to utilize hundreds of acres of polar bear and caribou habitat as an industrial oil field, resulting in negative impacts to many more acres of this important wildlife habitat. Surface mining utterly destroys entire landscapes and watersheds. The strip-mining of coal in central Appalachia has destroyed over 1.5 million acres of forest, leveled over 500 mountains, buried more than 200 miles of streams and headwaters, and poisoned waters downstream.   

What happens when biodiversity decreases? 

Without biodiversity, cultural and ecological landscapes begin to collapse. While the take of plants and animals happens for various reasons, namely to benefit human industry or eliminate large predators, it is a major driver of biodiversity loss.   

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John Morrison - iStock

Effects of overexploitation on biodiversity 

Overexploitation of plants and animals is the second major cause of biodiversity loss around the world behind habitat loss 

For example, apex carnivores are essential for a balanced ecosystem – of which humans are included and mutually benefit. Wolves, which were at one point systematically eliminated throughout the western United States, are a great refence to the checks and balances in an ecosystem.  

In areas outside of  Yellowstone National Park, wolf packs were once targeted by hunters. When the wolves were listed under the Endangered Species Act in 1973, populations of prey species, like elk, had already overgrazed the land and riverbank vegetation. Streamside vegetation growth was suppressed, eliminating habitat for beavers, birds, fish and even insects which further degraded the quality of local waterways and habitat for numerous wildlife. 

Following a successful wolf reintroduction campaign 70 years after they were extirpated, the streams and rivers and their wildlife in Yellowstone flourished again.    

Overexploitation is the thumb on the scale of a balanced ecosystem.  

All life in nature depends on each other in a delicate ecosystem. As Defenders’ President and CEO Jamie Rappaport-Clark says, “we are all connected.” When one species is removed from its natural habitat, its absence causes a ripple effect all the way through the ecosystem.