What Are the Consequences of Biodiversity Loss?

Last updated: January 2026

Life is resilient. After a hurricane barrels through — uprooting trees, relocating entire microecosystems, and lifting sections of beach sand only to drop them into tropical wetlands — nature begins to respond. In the eerie calm that follows, opportunistic species such as plants, insects, microorganisms, reptiles, amphibians, small mammals, and migrating birds rush in to fill the void. Ecosystems begin to rebuild, altered but often still functional.

This resilience can also be observed after wildfires, where new species emerge as landscapes recover. Over millions of years, evolution has produced a rich diversity of life that allows ecosystems to regenerate when given the chance. This ecosystem resilience depends on biodiversity — the variety of species, genes, and ecosystems that support natural recovery processes.

However, recent environmental change is occurring faster and on a larger scale than at any other point in human history. As human influence intensifies, we must ask a critical question: how much biodiversity loss can ecosystems absorb before their ability to recover breaks down?

How much biodiversity can be lost before we can no longer rely on Earth to provide essential ecosystem services such as breathable air, clean water, fertile soil, and food?

The global population is approaching nine billion people. Yes, that is nine billion consumers! Beyond consuming water and food, modern societies consume vast quantities of material goods. Their production, use, and disposal pollute air and water, degrade ecosystems, and render large areas of soil infertile, accelerating biodiversity loss worldwide.

The direct consequences of biodiversity loss in present times

Life on Earth is deeply interconnected. Species depend on one another and on healthy ecosystems to survive.

Plants rely on insects and microorganisms to grow, while insects and microorganisms depend on plants for food and habitat. Plants help purify the air, control soil erosion, and moderate Earth’s climate. Healthy soil filters water, supports microorganisms, and enables plant growth.

Understanding the direct consequences of biodiversity loss helps explain why ecosystems are becoming less resilient. Human activities increasingly disrupt these systems, often far from where the impacts are ultimately felt.

#1 Urban sprawl

Urban sprawl leaves lasting consequences for biodiversity and ecosystem stability. As cities expand and natural land is converted for urban use, the loss and fragmentation of habitats reshape ecosystems in ways that are often irreversible.

When habitats are broken into smaller, disconnected patches, ecosystems lose their continuity. Populations of plants and animals that once interacted across large areas become isolated, reducing genetic diversity and weakening long-established ecological relationships. Over time, these fragmented systems support fewer species and become less balanced.

A well-documented example of this pattern can be seen in urbanized regions of North America, where habitat fragmentation has altered predator–prey relationships. Coyotes, which are highly adaptable, often thrive in fragmented urban landscapes, in cities like Chicago, Toronto, LA, while many smaller or less adaptable species decline. As their other natural predators and competitors disappear, these imbalances lead to coyote overpopulation, disrupted food webs, human conflict and further pressure on already reduced wildlife populations.

Because urban landscapes are largely permanent, the ecological consequences of urban sprawl persist long after construction ends. Once biodiversity is reduced and ecosystems are simplified, their capacity to recover remains limited even if additional development slows.

#2 Unsustainable agricultural techniques

The long-term consequences of modern industrial agriculture are increasingly visible across landscapes worldwide. What began as an effort to increase food production has resulted in farming systems that simplify ecosystems, reduce biological diversity, and weaken the natural processes that support life in agricultural regions.

Where intensive agricultural practices dominate, biodiversity declines both above and below ground. Large areas of land become ecologically uniform, supporting fewer plant and animal species and disrupting long-established relationships between soil organisms, plants, insects, and wildlife. Over time, these simplified systems lose their ability to regulate themselves.

One of the most persistent consequences is soil degradation. Repeated disturbance, heavy machinery use, and chemical inputs reduce soil fertility and biological activity. The complex fungal networks and microorganisms that once supported healthy soils decline, leaving land increasingly dependent on external inputs and less capable of sustaining diverse life.

Chemical residues from fertilizers, herbicides, and pesticides extend these impacts beyond farm fields. Runoff into nearby streams and groundwater reduces water quality and affects aquatic ecosystems, while non-target species such as birds, bees, and other pollinators decline as exposure accumulates over time.

As soil health deteriorates and biodiversity diminishes, agricultural landscapes become less resilient. Degraded land supports fewer species and recovers slowly, if at all, from disturbance. In response, farming often expands into new areas, leaving behind landscapes that are biologically impoverished and increasingly difficult to restore.

This pattern can be seen in regions such as the Amazon rainforest, where large areas have been converted to cattle pasture, and in Southeast Asia, where oil palm plantations have replaced diverse tropical forests. These conversions result in the near-total loss of complex ecosystems and the disappearance of species that depend on them, including orangutans.

When diverse ecosystems are replaced by monocultures, ecological interactions collapse. A palm oil plantation, for example, is largely silent compared to the rainforest it replaces. The intricate web of insects, birds, mammals, and microorganisms is reduced to a simplified system with limited ecological function.

Such systems are inherently unstable. With few natural predators or competitors remaining, pests and diseases spread more easily, further reducing biodiversity and reinforcing long-term ecological imbalance.

A more detailed discussion of these dynamics can be found in our article on the disadvantages of monoculture farming.

#3 Deforestation

The loss of forests leaves far-reaching and long-lasting consequences for biodiversity and climate stability. When forest ecosystems are degraded or removed, the effects extend well beyond the immediate loss of trees, reshaping ecological processes at local, regional, and global scales.

Forests (especially tropical forests) play a central role in regulating the Earth’s climate by storing large amounts of carbon. As forest cover declines, this function weakens or is lost entirely. In some regions, forest ecosystems that once absorbed carbon now contribute to atmospheric carbon levels, altering climate patterns and intensifying environmental instability.

Only a few large forest systems still retain enough intact structure to function as strong carbon sinks. The Congo rainforest, for example, remains one of the last tropical forests capable of absorbing more carbon than it releases. Elsewhere, this balance has already been disrupted.

The Amazon rainforest remains a net carbon sink, but extensive degradation has pushed large areas toward a critical threshold. As forest structure is simplified and fire becomes more frequent, the ecological conditions that sustain a stable rainforest begin to break down. This shift threatens not only regional biodiversity but also broader climate systems.

Similar consequences are already evident in Southeast Asia, where the removal of primary forests for timber extraction and oil palm plantations has transformed forested landscapes into net sources of carbon emissions. These changes reflect a loss of ecosystem function that persists long after clearing ends.

At the ecosystem level, deforestation results in lasting habitat loss and fragmentation. Once continuous forests are reduced to isolated patches, many species lose the environmental conditions they depend on to survive. Forest interiors disappear and microclimates change.

For plants, these changes alter light availability, humidity, temperature, and nutrient cycles. For animals, the loss of forest structure reduces shelter, food sources, and opportunities for reproduction.

Less adaptable species are particularly affected. Even small changes in forest conditions may exceed their tolerance limits, leading to population declines or local disappearance.

#4 Overexploitation of natural resources and living organisms

For a long time, Earth’s natural resources were treated as if they were limitless. Timbering, mining, quarrying, drilling for oil and gas, trapping, hunting, and fishing reflected the belief that nature existed primarily as a source of goods for human use.

Over time, it has become clear that these resources are finite. The toxic byproducts of extraction and refining degrade ecosystems, fossil fuel combustion accelerates climate warming and ocean acidification, and petroleum-based products such as plastics accumulate in waterways and food chains. At the same time, overexploitation of wildlife and marine resources has driven population declines and increased extinction risk.

As the global population has grown and consumption has intensified, pressure on natural systems has increased. When extraction and harvest exceed natural regeneration rates, ecosystems lose their ability to recover, leading to biodiversity loss across land and sea.

I. Exotic animal and plant trade

The trade in exotic animals and plants is a significant driver of ecological imbalance. Capturing wild animals for trade removes individuals from their ecosystems and can disrupt population structure, reproduction, and species interactions.

Introduced species may become invasive when released or escaped into non-native environments. The Burmese python in Florida’s Everglades, for example, has severely reduced populations of small mammals, while invasive lionfish have spread rapidly across Atlantic and Caribbean coral reefs, preying on native species and destabilizing reef ecosystems.

Invasive plant species introduced through trade can cause similar damage. Once established, fast-growing non-native plants may outcompete local vegetation, reducing habitat quality for insects, birds, amphibians, and other wildlife that depend on native plant communities.

These examples highlight how the exotic species trade can unintentionally trigger long-lasting ecological disruption.

II. Overhunting and wildlife exploitation

Overhunting has placed many mammal and bird species at risk of extinction. Animals are hunted for food, traditional medicine, and trophies, often targeting large or reproductively important individuals.

The removal of top predators or dominant individuals can destabilize ecosystems. When predator populations decline, prey species may increase unchecked, leading to vegetation loss and further ecosystem degradation — a process known as food web disruption.

Beyond ecological impacts, unsustainable hunting also affects local communities. Wildlife provides long-term economic value through ecosystem services and sustainable tourism, while unregulated hunting concentrates short-term gains among few individuals and reduces long-term benefits.

Increased contact between humans and wild animals through hunting and trade also raises the risk of zoonotic disease transmission, adding a public-health dimension to biodiversity loss.

III. Overfishing and marine resource depletion

Overfishing is one of the most severe forms of overexploitation.

As our global population is growing, the demand for seafood is increasing as well. In some countries, seafood is the main source of protein. Across the world, 3.3 billion people obtain 20 percent of their animal protein from fish and seafood, according to the recent FAO’s statistics.

As demand for seafood increases, fishing pressure intensifies. At the same time, warming oceans, pollution, and habitat degradation reduce the capacity of marine ecosystems to replenish fish populations. Destructive fishing practices and high levels of bycatch further damage marine biodiversity.

Food waste compounds the problem. A significant proportion of fish caught is lost during processing or discarded, increasing pressure on already declining stocks. Without changes in how marine resources are managed, continued overfishing threatens both food security and the biodiversity of ocean ecosystems.

Further reading: A Deeper Look into Overfishing

#5 Tourism

Transportation accounted for 24 percent of greenhouse gas emissions globally in 2016 [4], and 29 percent of greenhouse gas emissions in the United States in 2019 [5]. But travel-related emissions are just one component of the ecological footprint of tourism.

Accommodation and destination infrastructure also play a major role. Tourism often increases waste generation, water consumption, and energy use, while single-use disposable products and food waste add further pressure on local environments. In heavily visited areas, wildlife disturbance, trampling of vegetation, and the conversion of natural land into roads, parking areas, and entertainment facilities degrade habitats and reduce biodiversity.

When destinations become overcrowded during peak seasons, environmental impacts intensify. Sensitive ecosystems and local cultures can be pushed beyond their capacity to recover, leading to long-term ecological degradation.

Ecotourism and unintended impacts

A modern buzz word in the tourism industry is ecotourism. At its best, ecotourism means vacationing with a light impact on the environment. At its worst, ecotourism is a bald marketing ploy to attract the progressively conscientious travelers, while in fact it still adversely impacts the surrounding environment. Who wouldn’t like to travel to an exotic location to relax with all the amenities of the modern world at their disposal: comfortable beds, spa treatments, culinary extravaganzas and partaking of unusual adventures, often ostensibly nature-focused?

Increased visitation to fragile environments, even when well intentioned, can disrupt wildlife behavior, increase resource consumption, and generate waste. Without strict limits and careful management, tourism labeled as ecotourism may still contribute to habitat degradation and biodiversity loss.

Wildlife disturbance and habitat degradation

Tourism-related activities frequently disturb wildlife. In popular natural areas, visitors leaving designated trails can trample vegetation and damage habitats, including those supporting endangered plant species. Recreational activities may disrupt feeding, breeding, and migration patterns of animals.

In some cases, tourism overlaps with wildlife exploitation. Hunting expeditions targeting declining species can further reduce already vulnerable populations, compounding biodiversity loss.

Marine tourism and ocean impacts

Marine tourism adds persistent pressure to ocean ecosystems. Cruise ships and recreational boating contribute to air pollution and greenhouse gas emissions, while wastewater discharge, fuel residues, and toxic anti-fouling paints contaminate marine environments.

Noise pollution has become an additional concern. Many marine species rely on sound for communication, navigation, and feeding. Chronic underwater noise interferes with these processes, increasing stress and reducing reproductive success in affected populations.

Further reading: Environmental Impacts of Tourism

#6 Unsustainable water management

Water aquifers have a limited amount of water at any given time and rely upon rains for replenishment. When we draw more water than there is naturally available, the aquifers run dry.

Many manufacturing practices and industry sectors, like power plants and metal refining, require large amounts of water. Unfortunately, in many cases, we do not have the technological capacity to filter the heavily toxic byproducts, so the water becomes too polluted for any other use. This water cannot be freely released back into natural environment, which means that it becomes unavailable for aquatic life or plants to benefit from.

Intensive agriculture requires a lot of water and causes biodiversity loss by severely degrading lands in many areas around the globe. For example, lack of water to support farming and desert sands encroaching villages are already causing trouble to rice farmers throughout the regions of northern China. While farmers despair about their inability to cultivate rice fields, local agronomists confirm that it was the water overextraction to create rice paddies that has significantly contributed to the current desert expansion in the area, wiping off native life along with it.

A similarly sad story is that of the Aral Sea. Once one of the largest freshwater lakes in the world has been destroyed by inconsiderate irrigation projects along the rivers which fed the lake. This resulted in the loss of much of the lake water and a total disappearance of the original lake ecosystem with the abundance of fish that would support coastal communities. More details are in our article: The Aral Sea Disaster.

Alternative agricultural practices for sustainable food production must be found if we are to preserve available water resources for drinking. In many desert areas where water supply is already low, people insist on maintaining green yards and growing modern, high-production crop varieties that are not good fit for the given area. It is important to consider this and plant drought-resistant crops and ornamental plants for backyards.

In many parts of the world, conflicts arise where one political subdivision diverts water from another downstream. We need to work together. Water management involves transboundary cooperation and equal allocation of this precious resource to residents.

Additionally, we are currently witnessing alarmingly high temperatures on poles and higher elevations which affect the stability of the permanent ice mass. The world’s biggest glaciers are melting and start to threaten the water supply of hundreds of millions of people in Southeast Asia in coming years [12].

#7 Climate change

One of the most visible consequences of climate change is the warming of the oceans. As seawater absorbs excess heat and carbon dioxide, coral reefs bleach and weaken, losing their ability to support the diverse communities of fish and invertebrates that depend on them. Ocean warming also alters currents and nutrient cycles, disrupting marine food webs far beyond tropical regions.

On land, rising temperatures and prolonged droughts increase the frequency and intensity of wildfires. While fire is a natural part of some ecosystems, the scale and severity of modern wildfires exceed historical patterns, destroying habitats faster than they can recover. Forests, grasslands, and wetlands that once acted as carbon sinks may become sources of greenhouse gas emissions after repeated burning.

Climate change also affects freshwater ecosystems. Reduced snowpack, earlier snowmelt, and altered rainfall patterns change river flows and lake levels, threatening species adapted to specific water conditions. As water bodies warm and shrink, oxygen levels decline, further stressing aquatic life.

In polar and high-altitude regions, melting ice is transforming entire ecosystems. Species that depend on ice-covered environments are losing habitat, while newly exposed land and water alter predator–prey relationships. These changes ripple outward, affecting global climate systems and biodiversity far beyond the poles.

Together, these impacts show that climate change does not act in isolation. It amplifies other pressures such as habitat loss, pollution, and overexploitation, pushing ecosystems closer to thresholds from which recovery may no longer be possible. As environmental conditions continue to shift, biodiversity loss accelerates, weakening the natural systems that sustain life on Earth.

These points all bring us to the question…

How big is the human impact on biodiversity?

Half of the world’s habitable land including forests, wetlands and grasslands, has been converted to agriculture since 1970, directly resulting in a 60 percent decline in the number of vertebrates worldwide.

The 2019 Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES) report cites that the average abundance of native species in most major land-based habitats has fallen by at least 20 percent since 1900 [13].

Presently, more than 40 percent of amphibian species, nearly 33 percent of reef-forming corals and more than a third of all marine mammals are threatened. Coral reef bleaching has accelerated with rising ocean temperatures and current studies show that 75 percent of reef corals are threatened [14].

The IPBES finds that one million plant and animal species are currently threatened with imminent extinction to human activities. The background rate of extinction, that is absent of human influence, is considered to be anywhere from one to five species per year.

As these numbers suggest human impact on biodiversity is great and devastating. What makes it even worse is that we are aware of our actions and can predict some of the impacts, but so far have been unable to change our behavior swiftly enough to start reverting or at least making up for the damage.

Sadly, environmental degradation is everywhere around us. While much attention has been focused on the polluting of our oceans and deservedly so, even a casual observation can confirm the pervasive degradation of rivers and lakes.

Rivers and lakes are the most degraded ecosystems in the world [15]. Poorly planned dams, introduction of invasive species for the pleasure of anglers, and pollution have all contributed to an 86 percent loss of freshwater vertebrate species since 1970.

We drive past mining waste, junkyards, power facilities spewing orange pollutants and surrounded by wastewater vats, paved and treeless urban neighborhoods and past slums reeking of human waste. More pastorally, we drive past agricultural fields, but this land too has been substantially degraded by the repeated application of toxic chemicals.

Over 75 percent of earth’s habitable land has been degraded. According to a March 2018 IPBES report on loss of biodiversity, over 95 percent of the world’s land could be substantially degraded by 2050 based on current trends [16].

92 percent of the world breathes unhealthy air. Cities currently with the worst air pollution include Johannesburg in South Africa, Hotan in China, Lahore in Pakistan, Riyadh in Saudi Arabia and Santiago in Chile [17]. Where there is unsustainable development and severe pollution, there is biodiversity loss.

Further reading: What Are the Major Threats to Biodiversity?

What is the effect of loss of biodiversity on ecosystems?

Biodiversity is essential for the stability and resilience of ecosystems. Healthy ecosystems supply clean air, fresh water, fertile soil, and regulate climate conditions within ranges that allow life to flourish.

When ecosystems lose a large portion of their biodiversity, they become increasingly fragile. Their ability to perform essential ecosystem services weakens, and they are less able to withstand disturbances such as extreme weather, disease, or further environmental stress. As biodiversity declines, ecosystems may reach tipping points beyond which recovery becomes slow or impossible.

The effects of biodiversity loss are already visible in many regions of the world.

Ecosystems severely affected by biodiversity loss

A striking example of severe biodiversity decline is the island of Borneo, once dominated by tropical rainforests, mangroves, and swamp ecosystems. Large tropical forests act as major carbon sinks, helping regulate the global climate. In Southeast Asia, however, extensive deforestation has disrupted this function, turning some forested regions from carbon sinks into net sources of carbon emissions.

Borneo’s forests are home to unique plant and animal species that have evolved over millions of years. Yet between 1973 and 2015, approximately half of the island’s forest cover was lost, largely due to the expansion of oil palm, rubber, and other industrial plantations. Although rates of primary forest loss in Malaysia and Indonesia have slowed in recent years, the ecological damage remains profound.

Another example is Australia’s Great Barrier Reef. Since the mid-1990s, the reef has lost a significant proportion of its coral cover and has experienced repeated mass bleaching events within a short time span. Coral reefs serve as nurseries for marine life and support complex food webs. Their decline reduces fish populations, weakens marine ecosystems, and threatens coastal communities that depend on healthy seas.

Coral reefs also act as natural barriers, protecting coastlines from storms and tidal surges. As reefs degrade, coastal ecosystems and human settlements become more vulnerable to natural disasters.

As species disappear, these changes can trigger trophic cascades, where disruptions at one level of the food web ripple through entire ecosystems.

Taken together, these examples illustrate a central consequence of biodiversity loss: once ecosystems are simplified, their ability to function, adapt, and recover is fundamentally reduced. The loss of biodiversity is not only a loss of species, but a loss of the natural systems that make the planet resilient and habitable.