Biodiversity loss happens when plant or animal
species
A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of Taxonomy (biology), ...
disappear completely from Earth (
extinction
Extinction is the termination of an organism by the death of its Endling, last member. A taxon may become Functional extinction, functionally extinct before the death of its last member if it loses the capacity to Reproduction, reproduce and ...
) or when there is a decrease or disappearance of species in a specific area. Biodiversity loss means that there is a reduction in
biological diversity
Biodiversity is the variability of life on Earth. It can be measured on various levels. There is for example genetic variability, species diversity, ecosystem diversity and phylogenetic diversity. Diversity is not distributed evenly on Eart ...
in a given area. The decrease can be temporary or permanent. It is temporary if the damage that led to the loss is reversible in time, for example through
ecological restoration
Ecological restoration, or ecosystem restoration, is the process of assisting the recovery of an ecosystem that has been degraded, damaged, destroyed or transformed. It is distinct from conservation in that it attempts to retroactively repair ...
. If this is not possible, then the decrease is permanent. The cause of most of the biodiversity loss is, generally speaking, human activities that push the
planetary boundaries
Planetary boundaries are a framework to describe limits to the impacts of human activities on the Earth system. Beyond these limits, the environment may not be able to continue to self-regulate. This would mean the Earth system would leave th ...
too far.
These activities include
habitat destruction
Habitat destruction (also termed habitat loss or habitat reduction) occurs when a natural habitat is no longer able to support its native species. The organisms once living there have either moved elsewhere, or are dead, leading to a decrease ...
(for example
deforestation
Deforestation or forest clearance is the removal and destruction of a forest or stand of trees from land that is then converted to non-forest use. Deforestation can involve conversion of forest land to farms, ranches, or urban use. Ab ...
) and
land use
Land use is an umbrella term to describe what happens on a parcel of land. It concerns the benefits derived from using the land, and also the land management actions that humans carry out there. The following categories are used for land use: fo ...
intensification (for example
monoculture
In agriculture, monoculture is the practice of growing one crop species in a field at a time. Monocultures increase ease and efficiency in planting, managing, and harvesting crops short-term, often with the help of machinery. However, monocultur ...
farming).
Further problem areas are
air
An atmosphere () is a layer of gases that envelop an astronomical object, held in place by the gravity of the object. A planet retains an atmosphere when the gravity is great and the temperature of the atmosphere is low. A stellar atmosph ...
and
water pollution
Water pollution (or aquatic pollution) is the contamination of Body of water, water bodies, with a negative impact on their uses. It is usually a result of human activities. Water bodies include lakes, rivers, oceans, aquifers, reservoirs and ...
(including
nutrient pollution
Nutrient pollution is a form of water pollution caused by too many Nutrient, nutrients entering the water. It is a primary cause of eutrophication of surface waters (lakes, rivers and Coast, coastal waters), in which excess nutrients, usually ni ...
),
over-exploitation
Overexploitation, also called overharvesting or ecological overshoot, refers to harvesting a renewable resource to the point of diminishing returns. Continued overexploitation can lead to the destruction of the resource, as it will be unable t ...
,
invasive species
An invasive species is an introduced species that harms its new environment. Invasive species adversely affect habitats and bioregions, causing ecological, environmental, and/or economic damage. The term can also be used for native spec ...
and
climate change
Present-day climate change includes both global warming—the ongoing increase in Global surface temperature, global average temperature—and its wider effects on Earth's climate system. Climate variability and change, Climate change in ...
.
Many scientists, along with the ''
'', say that the main reason for biodiversity loss is a
growing human population because this leads to
human overpopulation
Human overpopulation (or human population overshoot) is the idea that human populations may become too large to be sustainability, sustained by their environment or resources in the long term. The topic is usually discussed in the context of wor ...
and
excessive consumption.
Others disagree, saying that loss of habitat is caused mainly by "the growth of commodities for export" and that population has very little to do with overall consumption. More important are wealth disparities between and within countries.
In any case, all contemporary biodiversity loss has been attributed to human activities.
Climate change is another threat to
global biodiversity
Global biodiversity is the measure of biodiversity on planet Earth and is defined as the total variability of life forms. More than 99 percent of all species that ever lived on Earth are estimated to be extinct. Estimates on the number of Earth's ...
.
For example,
coral reef
A coral reef is an underwater ecosystem characterized by reef-building corals. Reefs are formed of colonies of coral polyps held together by calcium carbonate. Most coral reefs are built from stony corals, whose polyps cluster in group ...
s—which are
biodiversity hotspot
A biodiversity hotspot is a ecoregion, biogeographic region with significant levels of biodiversity that is threatened by human habitation. Norman Myers wrote about the concept in two articles in ''The Environmentalist'' in 1988 and 1990, after ...
s—will be lost by the year 2100 if global warming continues at the current rate.
Still, it is the general habitat destruction (often for expansion of agriculture), not climate change, that is currently the bigger driver of biodiversity loss.
Invasive species and other disturbances have become more common in forests in the last several decades. These tend to be directly or indirectly connected to climate change and can cause a deterioration of forest ecosystems.
Groups that care about the environment have been working for many years to stop the decrease in biodiversity. Nowadays, many global policies include activities to stop biodiversity loss. For example, the
UN Convention on Biological Diversity aims to prevent biodiversity loss and to conserve
wilderness areas. However, a 2020
United Nations Environment Programme
The United Nations Environment Programme (UNEP) is responsible for coordinating responses to environmental issues within the United Nations system. It was established by Maurice Strong, its first director, after the Declaration of the United Nati ...
report found that most of these efforts had failed to meet their goals. For example, of the 20 biodiversity goals laid out by the
Aichi Biodiversity Targets in 2010, only six were "partially achieved" by 2020.
This ongoing global extinction is also called the ''
holocene extinction
The Holocene extinction, also referred to as the Anthropocene extinction or the sixth mass extinction, is an ongoing extinction event caused exclusively by human activities during the Holocene epoch. This extinction event spans numerous families ...
'' or ''sixth mass extinction.''
Global estimates across all species

The current rate of
global biodiversity
Global biodiversity is the measure of biodiversity on planet Earth and is defined as the total variability of life forms. More than 99 percent of all species that ever lived on Earth are estimated to be extinct. Estimates on the number of Earth's ...
loss is estimated to be 100 to 1000 times higher than the (naturally occurring)
background extinction rate, faster than at any other time in human history, and is expected to grow in the upcoming years. The fast-growing extinction trends of various animal groups like mammals, birds, reptiles, amphibians, and fish have led scientists to declare a current biodiversity crisis in both land and ocean ecosystems.
In 2006, many more species were formally classified as
rare or
endangered
An endangered species is a species that is very likely to become extinct in the near future, either worldwide or in a particular political jurisdiction. Endangered species may be at risk due to factors such as habitat loss, poaching, inv ...
or
threatened; moreover, scientists have estimated that millions more species are at risk that have not been formally recognized.
Deforestation also plays a large role in biodiversity loss. More than half of the worlds biodiversity is hosted in tropical rainforest. Regions that are subjected to exponential loss of biodiversity are referred to as
biodiversity hotspot
A biodiversity hotspot is a ecoregion, biogeographic region with significant levels of biodiversity that is threatened by human habitation. Norman Myers wrote about the concept in two articles in ''The Environmentalist'' in 1988 and 1990, after ...
s. Since 1988 the hotspots increased from 10 to 34. Of the total 34 hotspots currently present, 16 of them are in tropical regions (as of 2006).
Researchers have noted in 2006 that only 2.3% of the world is covered with biodiversity loss hotspots, and even though only a small percentage of the world is covered in hotspots, it host a large fraction (50%) of
vascular plant
Vascular plants (), also called tracheophytes (, ) or collectively tracheophyta (; ), are plants that have lignin, lignified tissues (the xylem) for conducting water and minerals throughout the plant. They also have a specialized non-lignified Ti ...
species.
In 2021, about 28 percent of the 134,400 species assessed using the
IUCN Red List
The International Union for Conservation of Nature (IUCN) Red List of Threatened Species, also known as the IUCN Red List or Red Data Book, founded in 1964, is an inventory of the global conservation status and extinction risk of biological ...
criteria are now listed as threatened with
extinction
Extinction is the termination of an organism by the death of its Endling, last member. A taxon may become Functional extinction, functionally extinct before the death of its last member if it loses the capacity to Reproduction, reproduce and ...
—a total of 37,400 species compared to 16,119 threatened species in 2006.
A 2022 study that surveyed more than 3,000 experts found that "global biodiversity loss and its impacts may be greater than previously thought", and estimated that roughly 30% of species "have been globally threatened or driven extinct since the year 1500."
Research published in 2023 found that, out of 70,000 species, about 48% are facing decreasing populations due to human activities, while only 3% are seeing an increase in populations.
Methods to quantify loss
Biologists define ''biodiversity'' as the "totality of
gene
In biology, the word gene has two meanings. The Mendelian gene is a basic unit of heredity. The molecular gene is a sequence of nucleotides in DNA that is transcribed to produce a functional RNA. There are two types of molecular genes: protei ...
s,
species
A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of Taxonomy (biology), ...
and
ecosystems
An ecosystem (or ecological system) is a system formed by Organism, organisms in interaction with their Biophysical environment, environment. The Biotic material, biotic and abiotic components are linked together through nutrient cycles and en ...
of a region".
To measure biodiversity loss rates for a particular location, scientists record the
species richness
Species richness is the number of different species represented in an community (ecology), ecological community, landscape or region. Species richness is simply a count of species, and it does not take into account the Abundance (ecology), abunda ...
and its variation
over time in that area. In
ecology
Ecology () is the natural science of the relationships among living organisms and their Natural environment, environment. Ecology considers organisms at the individual, population, community (ecology), community, ecosystem, and biosphere lev ...
,
local abundance is the relative representation of a species in a particular
ecosystem
An ecosystem (or ecological system) is a system formed by Organism, organisms in interaction with their Biophysical environment, environment. The Biotic material, biotic and abiotic components are linked together through nutrient cycles and en ...
.
It is usually measured as the number of individuals found per
sample. The ratio of abundance of one species to one or multiple other species living in an ecosystem is called
relative species abundance.
Both indicators are relevant for
computing biodiversity.
There are many different
biodiversity indexes.
These investigate different scales and time spans.
Biodiversity has various scales and subcategories (e.g.
phylogenetic diversity Phylogenetic diversity is a measure of biodiversity which incorporates Phylogenetics, phylogenetic difference between species. It is defined and calculated as "the sum of the lengths of all those branches that are members of the corresponding minimu ...
,
species diversity
Species diversity is the number of different species that are represented in a given community (a dataset). The effective number of species refers to the number of equally abundant species needed to obtain the same mean proportional species abundan ...
,
genetic diversity
Genetic diversity is the total number of genetic characteristics in the genetic makeup of a species. It ranges widely, from the number of species to differences within species, and can be correlated to the span of survival for a species. It is d ...
,
nucleotide diversity Nucleotide diversity is a concept in molecular genetics which is used to measure the degree of polymorphism (biology), polymorphism within a population.
One commonly used measure of nucleotide diversity was first introduced by Masatoshi Nei, Nei a ...
).
The question of ''net loss'' in confined regions is often a matter of debate.
Observations by type of life
Wildlife in general
An October 2020 analysis by
Swiss Re
Swiss Re Ltd is a Swiss reinsurance company founded in 1863 and headquartered in Zürich, Switzerland. It is one of the world's largest reinsurers, as measured by gross premiums written. Swiss Re operates through around 80 offices in 29 countri ...
found that one-fifth of all countries are at risk of
ecosystem collapse
An ecosystem, short for ecological system, is defined as a collection of interacting organisms within a biophysical environment. Ecosystems are never static, and are continually subject to both stabilizing and destabilizing processes. Stabilizing ...
as the result of anthropogenic habitat destruction and increased
wildlife
Wildlife refers to domestication, undomesticated animals and uncultivated plant species which can exist in their natural habitat, but has come to include all organisms that grow or live wilderness, wild in an area without being species, introdu ...
loss. If these losses are not reversed, a total ecosystem collapse could ensue.
In 2022, the World Wildlife Fund reported an average population decline of 68% between 1970 and 2016 for 4,400 animal species worldwide, encompassing nearly 21,000 monitored populations.
Terrestrial invertebrates
Insects
Earthworms

Scientists have studied loss of
earthworm
An earthworm is a soil-dwelling terrestrial invertebrate that belongs to the phylum Annelida. The term is the common name for the largest members of the class (or subclass, depending on the author) Oligochaeta. In classical systems, they we ...
s from several long-term agronomic trials. They found that relative biomass losses of minus 50–100% (with a mean of minus 83%) match or exceed those reported for other faunal groups.
Thus it is clear that earthworms are similarly depleted in the soils of fields used for intensive agriculture.
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Creative Commons Attribution 4.0 International License
Earthworms play an important role in ecosystem function,
helping with biological processing in soil, water, and even greenhouse gas balancing.
There are five reasons for the decline of earthworm diversity: "(1)
soil degradation
Soil retrogression and degradation are two regressive evolution processes associated with the loss of equilibrium of a soil health, stable soil. Retrogression is primarily due to soil erosion and corresponds to a phenomenon where succession revert ...
and habitat loss, (2) climate change, (3) excessive nutrient and other forms of contamination load, (4) over-exploitation and unsustainable management of soil, and (5) invasive species".
Factors like tillage practices and intensive land use decimate the soil and plant roots that earthworms use to create their biomass. This interferes with
carbon
Carbon () is a chemical element; it has chemical symbol, symbol C and atomic number 6. It is nonmetallic and tetravalence, tetravalent—meaning that its atoms are able to form up to four covalent bonds due to its valence shell exhibiting 4 ...
and
nitrogen cycle
The nitrogen cycle is the biogeochemical cycle by which nitrogen is converted into multiple chemical forms as it circulates among atmosphere, atmospheric, terrestrial ecosystem, terrestrial, and marine ecosystems. The conversion of nitrogen can ...
s.
Knowledge of earthworm species diversity is quite limited as not even 50% of them have been described.
Sustainable agriculture
Sustainable agriculture is agriculture, farming in sustainability, sustainable ways meeting society's present food and textile needs, without compromising the ability for current or future generations to meet their needs. It can be based on an ...
methods could help prevent earthworm diversity decline, for example reduced tillage.
The Secretariat of the
Convention on Biological Diversity
The Convention on Biological Diversity (CBD), known informally as the Biodiversity Convention, is a multilateral treaty. The Convention has three main goals: the conservation of biological diversity (or biodiversity); the sustainable use of its ...
is trying to take action and promote the restoration and maintenance of the many diverse species of earthworms.
Amphibians
Wild mammals
Birds
Some
pesticide
Pesticides are substances that are used to control pests. They include herbicides, insecticides, nematicides, fungicides, and many others (see table). The most common of these are herbicides, which account for approximately 50% of all p ...
s, like
insecticide
Insecticides are pesticides used to kill insects. They include ovicides and larvicides used against insect eggs and larvae, respectively. The major use of insecticides is in agriculture, but they are also used in home and garden settings, i ...
s, likely play a role in reducing the populations of specific bird species. According to a study funded by
BirdLife International
BirdLife International is a global partnership of non-governmental organizations that strives to conserve birds and their habitats. BirdLife International's priorities include preventing extinction of bird species, identifying and safeguarding i ...
, 51 bird species are critically endangered and eight could be classified as extinct or in danger of extinction. Nearly 30% of extinction is due to hunting and trapping for the exotic pet trade.
Deforestation
Deforestation or forest clearance is the removal and destruction of a forest or stand of trees from land that is then converted to non-forest use. Deforestation can involve conversion of forest land to farms, ranches, or urban use. Ab ...
, caused by unsustainable logging and agriculture, could be the next extinction driver, because birds lose their habitat and their food.
Plants
Trees
While plants are essential for human survival, they have not received the same attention as the conservation of animals.
It is estimated that a third of all land plant species are at risk of extinction and 94% have yet to be evaluated in terms of their conservation status.
Plants existing at the lowest trophic level require increased conservation to reduce negative impacts at higher trophic levels.
In 2022, scientists warned that a third of tree species are threatened with extinction. This will significantly alter the world's ecosystems because their carbon, water and
nutrient cycle
A nutrient cycle (or ecological recycling) is the movement and exchange of inorganic and organic matter back into the production of matter. Energy flow is a unidirectional and noncyclic pathway, whereas the movement of mineral nutrients is cyc ...
s will be affected.
Forest areas are degraded due to common factors such as logging, fire, and firewood harvesting. The GTA (global tree assessment) has determined that "17,510 (29.9%) tree species are considered threatened with extinction. In addition, there are 142 tree species recorded as Extinct or Extinct in the Wild."
Possible solutions can be found in some
silvicultural
Silviculture is the practice of controlling the growth, composition/structure, as well as quality of forests to meet values and needs, specifically timber production.
The name comes from the Latin ('forest') and ('growing'). The study of forests ...
methods of
forest management
Forest management is a branch of forestry concerned with overall administrative, legal, economic, and social aspects, as well as scientific and technical aspects, such as silviculture, forest protection, and forest regulation. This includes man ...
that promote tree biodiversity, such as selective logging,
thinning
In agricultural sciences, thinning is the removal of some plants, or parts of plants, to make room for the growth of others. Selective removal of parts of a plant such as branches, buds, or roots is typically known as '' pruning''.
In forestry ...
or crop tree management, and
clear cutting
Clearcutting, clearfelling or clearcut logging is a forestry/logging practice in which most or all trees in an area are uniformly cut down. Along with Shelterwood cutting, shelterwood and Seed tree, seed tree harvests, it is used by foresters t ...
and
coppicing
Coppicing is the traditional method in woodland management of cutting down a tree to a tree stump, stump, which in many species encourages new Shoot (botany), shoots to grow from the stump or roots, thus ultimately regrowing the tree. A forest ...
. Without solutions,
secondary forest
A secondary forest (or second-growth forest) is a forest or woodland area which has regenerated through largely natural processes after human-caused Disturbance (ecology), disturbances, such as Logging, timber harvest or agriculture clearing, or ...
s recovery in
species richness
Species richness is the number of different species represented in an community (ecology), ecological community, landscape or region. Species richness is simply a count of species, and it does not take into account the Abundance (ecology), abunda ...
can take 50 years to recover the same amount as the primary forest, or 20 years to recover 80% of species richness.
Flowering plants
Freshwater species
Freshwater ecosystem
Freshwater ecosystems are a subset of Earth's aquatic ecosystems that include the biological communities inhabiting freshwater waterbodies such as lakes, ponds, rivers, streams, springs, bogs, and wetlands. They can be contrasted with marine ec ...
s such as swamps, deltas, and rivers make up 1% of earth's surface. They are important because they are home to approximately one third of
vertebrate
Vertebrates () are animals with a vertebral column (backbone or spine), and a cranium, or skull. The vertebral column surrounds and protects the spinal cord, while the cranium protects the brain.
The vertebrates make up the subphylum Vertebra ...
species.
Freshwater species are beginning to decline at twice the rate of species that live on land or in the ocean. This rapid loss has already placed 27% of 29,500 species dependent on fresh water on the
IUCN Red List
The International Union for Conservation of Nature (IUCN) Red List of Threatened Species, also known as the IUCN Red List or Red Data Book, founded in 1964, is an inventory of the global conservation status and extinction risk of biological ...
.
Global populations of freshwater fish are collapsing due to
water pollution
Water pollution (or aquatic pollution) is the contamination of Body of water, water bodies, with a negative impact on their uses. It is usually a result of human activities. Water bodies include lakes, rivers, oceans, aquifers, reservoirs and ...
and
overfishing
Overfishing is the removal of a species of fish (i.e. fishing) from a body of water at a rate greater than that the species can replenish its population naturally (i.e. the overexploitation of the fishery's existing Fish stocks, fish stock), resu ...
. Migratory fish populations have declined by 76% since 1970, and large "megafish" populations have fallen by 94% with 16 species declared extinct in 2020.
Marine species
Marine biodiversity encompasses any living organism that resides in the ocean or in
estuaries
An estuary is a partially enclosed coastal body of brackish water with one or more rivers or streams flowing into it, and with a free connection to the open sea. Estuaries form a transition zone between river environments and maritime environm ...
.
By 2018, approximately 240,000 marine species had been documented.
But many marine species—estimates range between 178,000 and 10 million oceanic species—remain to be described.
It is therefore likely that a number of rare species (not seen for decades in the wild) have already disappeared or are on the brink of extinction, unnoticed.
Human activities have a strong and detrimental influence on marine biodiversity. The main drivers of marine species extinction are habitat loss, pollution,
invasive species
An invasive species is an introduced species that harms its new environment. Invasive species adversely affect habitats and bioregions, causing ecological, environmental, and/or economic damage. The term can also be used for native spec ...
, and overexploitation.
Greater pressure is placed on marine ecosystems near coastal areas because of the human settlements in those areas.
Overexploitation has resulted in the extinction of over 25 marine species. This includes
seabird
Seabirds (also known as marine birds) are birds that are adaptation, adapted to life within the marine ecosystem, marine environment. While seabirds vary greatly in lifestyle, behaviour and physiology, they often exhibit striking convergent ...
s,
marine mammal
Marine mammals are mammals that rely on marine ecosystems for their existence. They include animals such as cetaceans, pinnipeds, sirenians, sea otters and polar bears. They are an informal group, unified only by their reliance on marine enviro ...
s,
algae
Algae ( , ; : alga ) is an informal term for any organisms of a large and diverse group of photosynthesis, photosynthetic organisms that are not plants, and includes species from multiple distinct clades. Such organisms range from unicellular ...
, and
fish
A fish (: fish or fishes) is an aquatic animal, aquatic, Anamniotes, anamniotic, gill-bearing vertebrate animal with swimming fish fin, fins and craniate, a hard skull, but lacking limb (anatomy), limbs with digit (anatomy), digits. Fish can ...
.
Examples of extinct marine species include
Steller's sea cow
Steller's sea cow (''Hydrodamalis gigas'') is an extinction, extinct sirenian described by Georg Wilhelm Steller in 1741. At that time, it was found only around the Commander Islands in the Bering Sea between Alaska and Russia; its range exte ...
(''Hydrodamalis gigas'') and the
Caribbean monk seal (''Monachus tropicalis''). Not all extinctions are because of humans. For example, in the 1930s, the eelgrass limpet (''
Lottia alveus'') became extinct in the Atlantic once the ''
Zostera marina''
seagrass
Seagrasses are the only flowering plants which grow in marine (ocean), marine environments. There are about 60 species of fully marine seagrasses which belong to four Family (biology), families (Posidoniaceae, Zosteraceae, Hydrocharitaceae and ...
population declined upon exposure to a disease. The ''Lottia alveus'' were greatly impacted because the ''Zostera marina'' were their sole habitats.
Causes
The main causes of current biodiversity loss are:
#
Habitat loss
Habitat destruction (also termed habitat loss or habitat reduction) occurs when a natural habitat is no longer able to support its native species. The organisms once living there have either moved elsewhere, or are dead, leading to a decrease ...
, fragmentation and
degradation;
for example
habitat fragmentation
Habitat fragmentation describes the emergence of discontinuities (fragmentation) in an organism's preferred environment (habitat), causing population fragmentation and ecosystem decay. Causes of habitat fragmentation include geological proces ...
for commercial and agricultural uses (specifically
monoculture
In agriculture, monoculture is the practice of growing one crop species in a field at a time. Monocultures increase ease and efficiency in planting, managing, and harvesting crops short-term, often with the help of machinery. However, monocultur ...
farming)
#
Land use
Land use is an umbrella term to describe what happens on a parcel of land. It concerns the benefits derived from using the land, and also the land management actions that humans carry out there. The following categories are used for land use: fo ...
intensification (and ensuing
land loss/habitat loss); a significant factor in loss of ecological services due to direct effects as well as biodiversity loss
#
Nutrient pollution
Nutrient pollution is a form of water pollution caused by too many Nutrient, nutrients entering the water. It is a primary cause of eutrophication of surface waters (lakes, rivers and Coast, coastal waters), in which excess nutrients, usually ni ...
and other forms of pollution (
air
An atmosphere () is a layer of gases that envelop an astronomical object, held in place by the gravity of the object. A planet retains an atmosphere when the gravity is great and the temperature of the atmosphere is low. A stellar atmosph ...
and
water pollution
Water pollution (or aquatic pollution) is the contamination of Body of water, water bodies, with a negative impact on their uses. It is usually a result of human activities. Water bodies include lakes, rivers, oceans, aquifers, reservoirs and ...
)
#
Overexploitation
Overexploitation, also called overharvesting or ecological overshoot, refers to harvesting a renewable resource to the point of diminishing returns. Continued overexploitation can lead to the destruction of the resource, as it will be unable to ...
and unsustainable use (for example
unsustainable fishing methods
Unsustainable fishing methods refers to the use of various fishing methods to capture or harvest fish at a rate that is Sustainability, unsustainable for fish populations. These methods facilitate destructive fishing practices that damage ocean Ec ...
,
overfishing
Overfishing is the removal of a species of fish (i.e. fishing) from a body of water at a rate greater than that the species can replenish its population naturally (i.e. the overexploitation of the fishery's existing Fish stocks, fish stock), resu ...
,
overconsumption
Overconsumption describes a situation where consumers overuse their available goods and services to where they can't, or don't want to, replenish or reuse them. In microeconomics, this is the point where the marginal cost of a consumer is greater ...
and
human overpopulation
Human overpopulation (or human population overshoot) is the idea that human populations may become too large to be sustainability, sustained by their environment or resources in the long term. The topic is usually discussed in the context of wor ...
)
#
Invasive species
An invasive species is an introduced species that harms its new environment. Invasive species adversely affect habitats and bioregions, causing ecological, environmental, and/or economic damage. The term can also be used for native spec ...
that effectively
compete
Competition is a rivalry where two or more parties strive for a common goal which cannot be shared: where one's gain is the other's loss (an example of which is a zero-sum game). Competition can arise between entities such as organisms, individ ...
for a niche, replacing
indigenous species
In biogeography, a native species is indigenous to a given region or ecosystem if its presence in that region is the result of only local natural evolution (though often popularised as "with no human intervention") during history. The term is equi ...
#
Climate change
Present-day climate change includes both global warming—the ongoing increase in Global surface temperature, global average temperature—and its wider effects on Earth's climate system. Climate variability and change, Climate change in ...
(e.g.
extinction risk from climate change,
effects of climate change on plant biodiversity
There is an ongoing decline in plant biodiversity, just like there is ongoing biodiversity loss for many other life forms. One of the causes for this decline is climate change. Environmental conditions play a key role in defining the function an ...
)
Jared Diamond
Jared Mason Diamond (born September 10, 1937) is an American scientist, historian, and author. In 1985 he received a MacArthur Genius Grant, and he has written hundreds of scientific and popular articles and books. His best known is '' Guns, G ...
describes an "Evil Quartet" of
habitat destruction
Habitat destruction (also termed habitat loss or habitat reduction) occurs when a natural habitat is no longer able to support its native species. The organisms once living there have either moved elsewhere, or are dead, leading to a decrease ...
,
overkill,
introduced species
An introduced species, alien species, exotic species, adventive species, immigrant species, foreign species, non-indigenous species, or non-native species is a species living outside its native distributional range, but which has arrived ther ...
and
secondary extinctions.
Edward O. Wilson suggested the
acronym
An acronym is a type of abbreviation consisting of a phrase whose only pronounced elements are the initial letters or initial sounds of words inside that phrase. Acronyms are often spelled with the initial Letter (alphabet), letter of each wor ...
HIPPO for the main causes of biodiversity loss: Habitat destruction, Invasive species, Pollution,
human over-Population and
Over-harvesting.
Habitat destruction

For example, habitat loss is one of the causes in the decline of insect populations (see
the section below on insects).
Urban growth and habitat fragmentation
The direct effects of urban growth on habitat loss are well understood: building construction often results in habitat destruction and fragmentation.
This leads to selection for species that are adapted to urban environments. Small habitat patches cannot support the level of genetic or taxonomic diversity they formerly could while some more sensitive species may become locally extinct.
Species abundance
In ecology, local abundance is the relative representation of a species in a particular ecosystem. It is usually measured as the number of individuals found per sample. The ratio of abundance of one species to one or multiple other species livin ...
populations are reduced due to the reduced fragmented area of habitat. This causes an increase of species isolation and forces species toward edge habitats and to adapt to foraging elsewhere.
Additionally, edge effects often result in altered light, temperature, and humidity conditions that change vegetation structure and microhabitat suitability, further reducing biodiversity in fragmented urban patches. Urban environments also favor fast-reproducing, mobile species, contributing to biotic homogenization and the global decline of ecological uniqueness.
Infrastructure
Infrastructure is the set of facilities and systems that serve a country, city, or other area, and encompasses the services and facilities necessary for its economy, households and firms to function. Infrastructure is composed of public and pri ...
development in
Key Biodiversity Areas Key Biodiversity Areas (KBA) are geographical regions that have been determined to be of international importance in terms of biodiversity conservation, using globally standardized criteria published by the IUCN as part of a collaboration between sc ...
(KBA) is a major driver of biodiversity loss, with infrastructure present in roughly 80% of KBAs.
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Creative Commons Attribution 4.0 International License
Infrastructure development leads to conversion and fragmentation of natural habitat, pollution and disturbance. There can also be direct harm to animals through collisions with vehicles and structures. This can have impacts beyond the infrastructure site.
For example, chronic noise from roads can interfere with bird song used in mating and territory defense, reducing reproductive success. Artificial lighting can disrupt nocturnal foraging patterns, predator-prey interactions, and migratory navigation in species such as bats, amphibians, and sea turtles. Infrastructure can also create ecological traps, where animals are drawn to altered environments that ultimately reduce their fitness or survival. Furthermore, road mortality and bird collisions with buildings and power lines cause direct harm to wildlife, with cascading impacts across trophic levels. These impacts often extend well beyond the development footprint and may disrupt landscape connectivity critical for migration and climate adaptation. Fragmented landscapes also impede species’ range shifts in response to climate change, making it harder for populations to track suitable environmental conditions and increasing extinction risk.
Land use intensification
Humans are changing the uses of land in various ways, and each can lead to habitat destruction and biodiversity loss. The 2019 ''
'' found that industrial agriculture is the primary driver of biodiversity collapse.
The UN's Global Biodiversity Outlook 2014 estimated that 70% of the projected loss of terrestrial biodiversity is
caused by agriculture use.This is supported by more recent findings from the 2022 ''Global Land Outlook'' report by the UN Convention to Combat Desertification, which states that over 50% of agricultural land is moderately or severely degraded. According to a 2005 publication, "Cultivated systems
..cover 24% of Earth's surface".
The publication defined ''cultivated areas'' as "areas in which at least 30% of the landscape is in croplands, shifting cultivation, confined livestock production, or freshwater aquaculture in any particular year".
As of 2023, approximately 38% of the Earth's terrestrial surface is used for agriculture, including grazing and crop production, making it the dominant land use globally.
More than 17,000 species are at risk of losing habitat by 2050 as agriculture continues to expand to meet future food needs (as of 2020).
A global shift toward largely
plant-based diet
A plant-based diet is a diet consisting mostly or entirely of plant-based foods. It encompasses a wide range of dietary patterns that contain low amounts of animal products and high amounts of fiber-rich plant products such as vegetables ...
s would free up land to allow for the restoration of ecosystems and biodiversity.
In the 2010s over 80% of all global farmland was used to rear animals.
Recent FAO data shows that livestock systems occupy about 77% of agricultural land while providing less than 20% of the global calorie supply — highlighting an imbalance between land use and nutritional output.
As of 2022, 44% of Earth's land area required conservation attention, which may include declaring
protected area
Protected areas or conservation areas are locations which receive protection because of their recognized natural or cultural values. Protected areas are those areas in which human presence or the exploitation of natural resources (e.g. firewood ...
s and following
land-use policies. Additionally, a 2023 analysis in ''Science Advances'' concluded that at least 30% of land must be actively protected and ecologically restored by 2030 to meet global biodiversity goals, aligning with the Kunming-Montreal Global Biodiversity Framework agreed upon at COP15.
Nutrient pollution and other forms of pollution
Air pollution
Air pollution
Air pollution is the presence of substances in the Atmosphere of Earth, air that are harmful to humans, other living beings or the environment. Pollutants can be Gas, gases like Ground-level ozone, ozone or nitrogen oxides or small particles li ...
adversely affects biodiversity. Pollutants are emitted into the atmosphere by the burning of
fossil fuel
A fossil fuel is a flammable carbon compound- or hydrocarbon-containing material formed naturally in the Earth's crust from the buried remains of prehistoric organisms (animals, plants or microplanktons), a process that occurs within geolog ...
s and
biomass
Biomass is a term used in several contexts: in the context of ecology it means living organisms, and in the context of bioenergy it means matter from recently living (but now dead) organisms. In the latter context, there are variations in how ...
, for example. Industrial and agricultural activity releases the pollutants
sulfur dioxide
Sulfur dioxide (IUPAC-recommended spelling) or sulphur dioxide (traditional Commonwealth English) is the chemical compound with the formula . It is a colorless gas with a pungent smell that is responsible for the odor of burnt matches. It is r ...
and
nitrogen oxide
Nitrogen oxide may refer to a binary compound of oxygen and nitrogen, or a mixture of such compounds:
Charge-neutral
*Nitric oxide (NO), nitrogen(II) oxide, or nitrogen monoxide
* Nitrogen dioxide (), nitrogen(IV) oxide
* Nitrogen trioxide (), o ...
s.
Once sulfur dioxide and nitrogen oxide are introduced into the atmosphere, they can react with cloud droplets (
cloud condensation nuclei), raindrops, or snowflakes, forming
sulfuric acid
Sulfuric acid (American spelling and the preferred IUPAC name) or sulphuric acid (English in the Commonwealth of Nations, Commonwealth spelling), known in antiquity as oil of vitriol, is a mineral acid composed of the elements sulfur, oxygen, ...
and
nitric acid
Nitric acid is an inorganic compound with the formula . It is a highly corrosive mineral acid. The compound is colorless, but samples tend to acquire a yellow cast over time due to decomposition into nitrogen oxide, oxides of nitrogen. Most com ...
. With the interaction between water droplets and sulfuric and nitric acids,
wet deposition occurs and creates
acid rain
Acid rain is rain or any other form of Precipitation (meteorology), precipitation that is unusually acidic, meaning that it has elevated levels of hydrogen ions (low pH). Most water, including drinking water, has a neutral pH that exists b ...
.
A 2009 review studied four air pollutants (sulfur, nitrogen, ozone, and mercury) and several types of ecosystems.
Air pollution affects the functioning and biodiversity of terrestrial as well as aquatic ecosystems.
For example, "air pollution causes or contributes to acidification of lakes,
eutrophication
Eutrophication is a general term describing a process in which nutrients accumulate in a body of water, resulting in an increased growth of organisms that may deplete the oxygen in the water; ie. the process of too many plants growing on the s ...
of estuaries and coastal waters, and mercury bioaccumulation in aquatic food webs".
Noise pollution
Noise generated by traffic, ships, vehicles, and aircraft can affect the survivability of wildlife species and can reach undisturbed habitats.
Noise pollution
Noise pollution, or sound pollution, is the propagation of noise or sound with potential harmful effects on humans and animals. The source of outdoor noise worldwide is mainly caused by machines, transport and propagation systems.Senate Publi ...
is common in marine ecosystems, affecting at least 55 marine species.
One study found that as
seismic noises and
naval sonar increases in marine ecosystems,
cetacea
Cetacea (; , ) is an infraorder of aquatic mammals belonging to the order Artiodactyla that includes whales, dolphins and porpoises. Key characteristics are their fully aquatic lifestyle, streamlined body shape, often large size and exclusively c ...
n diversity decreases (including whales and dolphins). Multiple studies have found that fewer fishes, such as
cod
Cod (: cod) is the common name for the demersal fish genus ''Gadus'', belonging to the family (biology), family Gadidae. Cod is also used as part of the common name for a number of other fish species, and one species that belongs to genus ''Gad ...
,
haddock
The haddock (''Melanogrammus aeglefinus'') is a saltwater ray-finned fish from the Family (biology), family Gadidae, the true cods. It is the only species in the Monotypy, monotypic genus ''Melanogrammus''. It is found in the North Atlantic Oce ...
,
rockfish,
herring
Herring are various species of forage fish, belonging to the Order (biology), order Clupeiformes.
Herring often move in large Shoaling and schooling, schools around fishing banks and near the coast, found particularly in shallow, temperate wate ...
, sand seal, and
blue whiting, have been spotted in areas with seismic noises, with catch rates declining by 40–80%.
Noise pollution has also altered avian communities and diversity. Noise can reduce reproductive success, minimize nesting areas, increase stress response, and reduce species abundance.
Noise pollution can alter the distribution and abundance of prey species, which can then impact predator populations.
Pollution from fossil fuel extraction
Fossil fuel
A fossil fuel is a flammable carbon compound- or hydrocarbon-containing material formed naturally in the Earth's crust from the buried remains of prehistoric organisms (animals, plants or microplanktons), a process that occurs within geolog ...
extraction and associated oil and gas pipelines have major impacts on the biodiversity of many
biome
A biome () is a distinct geographical region with specific climate, vegetation, and animal life. It consists of a biological community that has formed in response to its physical environment and regional climate. In 1935, Tansley added the ...
s due to land conversion,
habitat loss
Habitat destruction (also termed habitat loss or habitat reduction) occurs when a natural habitat is no longer able to support its native species. The organisms once living there have either moved elsewhere, or are dead, leading to a decrease ...
and degradation, and pollution. An example is the Western
Amazon
Amazon most often refers to:
* Amazon River, in South America
* Amazon rainforest, a rainforest covering most of the Amazon basin
* Amazon (company), an American multinational technology company
* Amazons, a tribe of female warriors in Greek myth ...
region.
Exploitation of
fossil fuels
A fossil fuel is a flammable carbon compound- or hydrocarbon-containing material formed naturally in the Earth's crust from the buried remains of prehistoric organisms (animals, plants or microplanktons), a process that occurs within geologica ...
there has had significant impacts on biodiversity.
[ Text was copied from this source, which is available under ]
Creative Commons Attribution 4.0 International License
As of 2018, many of the
protected area
Protected areas or conservation areas are locations which receive protection because of their recognized natural or cultural values. Protected areas are those areas in which human presence or the exploitation of natural resources (e.g. firewood ...
s with rich biodiversity were in areas containing unexploited
fossil fuel reserves worth between $3 and $15 trillion.
The protected areas may be under threat in future.
Overexploitation
Continued
overexploitation
Overexploitation, also called overharvesting or ecological overshoot, refers to harvesting a renewable resource to the point of diminishing returns. Continued overexploitation can lead to the destruction of the resource, as it will be unable to ...
can lead to the destruction of the resource, as it will be unable to replenish. The term applies to
natural resource
Natural resources are resources that are drawn from nature and used with few modifications. This includes the sources of valued characteristics such as commercial and industrial use, aesthetic value, scientific interest, and cultural value. ...
s such as
water aquifers,
grazing pastures and
forests
A forest is an ecosystem characterized by a dense community of trees. Hundreds of definitions of forest are used throughout the world, incorporating factors such as tree density, tree height, land use, legal standing, and ecological functio ...
, wild
medicinal plant
Medicinal plants, also called medicinal herbs, have been discovered and used in traditional medicine practices since prehistoric times. Plants synthesize hundreds of chemical compounds for various functions, including Plant defense against h ...
s,
fish stocks
Fish stocks are population, subpopulations of a particular species of fish, for which intrinsic parameters (growth, recruitment, mortality and fishing mortality) are traditionally regarded as the significant factors determining the Population ...
and other
wildlife
Wildlife refers to domestication, undomesticated animals and uncultivated plant species which can exist in their natural habitat, but has come to include all organisms that grow or live wilderness, wild in an area without being species, introdu ...
.
Overfishing

A 2019
report
A report is a document or a statement that presents information in an organized format for a specific audience and purpose. Although summaries of reports may be delivered orally, complete reports are usually given in the form of written documen ...
found that overfishing is the main driver of mass species extinction in oceans. Overfishing has reduced fish and marine mammal
biomass
Biomass is a term used in several contexts: in the context of ecology it means living organisms, and in the context of bioenergy it means matter from recently living (but now dead) organisms. In the latter context, there are variations in how ...
by 60% since the 1800s. It is currently pushing over one-third of
shark
Sharks are a group of elasmobranch cartilaginous fish characterized by a ribless endoskeleton, dermal denticles, five to seven gill slits on each side, and pectoral fins that are not fused to the head. Modern sharks are classified within the ...
s and
rays toward extinction.
Many commercial fishes have been overharvested: a 2020
FAO
The Food and Agriculture Organization of the United Nations; . (FAO) is a List of specialized agencies of the United Nations, specialized agency of the United Nations that leads international efforts to defeat hunger and improve nutrition ...
report classified as overfished 34% of the fish stocks of the world's marine fisheries.
By 2020, global fish populations had declined 38% since 1970.
Many regulatory measures are available for controlling overfishing. These include
fishing quotas,
bag limits
A bag limit is a law imposed on hunters and fishermen restricting the number of animals within a specific species or group of species they may kill and keep. Size limits and hunting seasons sometimes accompany bag limits which place restrictions ...
, licensing,
closed seasons, size limits, and the creation of
marine reserves and other
marine protected areas
A marine protected area (MPA) is a protected area of the world's seas, oceans, estuary, estuaries or in the US, the Great Lakes. These marine areas can come in many forms ranging from wildlife refuges to research facilities. MPAs restrict human ...
.
Human overpopulation and overconsumption

The world's population numbered nearly 7.6 billion as of mid-2017 and is forecast to peak toward the end of the 21st century at 10–12 billion people.
Scholars have argued that population size and growth, along with
overconsumption
Overconsumption describes a situation where consumers overuse their available goods and services to where they can't, or don't want to, replenish or reuse them. In microeconomics, this is the point where the marginal cost of a consumer is greater ...
, are significant factors in biodiversity loss and soil degradation.
Review articles, including the 2019
IPBES
The Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES) is an intergovernmental organization established to improve communication between science and policy on issues of biodiversity and ecosystem services. It ...
report
A report is a document or a statement that presents information in an organized format for a specific audience and purpose. Although summaries of reports may be delivered orally, complete reports are usually given in the form of written documen ...
, have also noted that
human population growth and overconsumption are significant drivers of species decline.
A 2022 study warned that conservation efforts will continue to fail if the primary drivers of biodiversity loss continue to be ignored, including population size and growth.
Other scientists have criticized the assertion that population growth is a key driver for biodiversity loss.
They argue that the main driver is the loss of habitat, caused by "the growth of commodities for export, particularly soybean and oil-palm, primarily for livestock feed or
biofuel
Biofuel is a fuel that is produced over a short time span from Biomass (energy), biomass, rather than by the very slow natural processes involved in the formation of fossil fuels such as oil. Biofuel can be produced from plants or from agricu ...
consumption in higher income economies."
Because of the wealth disparities between countries, there is a negative correlation between a country's total population and its per capita footprint. On the other hand, the correlation between a country's GDP and its footprint is strong.
The study argues that population as a metric is unhelpful and counterproductive for tackling environmental challenges.
Invasive species
The term ''invasive'' is poorly defined and often very subjective.
The European Union defines ''
invasive alien species'' as those outside their natural distribution area that threaten
biological diversity
Biodiversity is the variability of life on Earth. It can be measured on various levels. There is for example genetic variability, species diversity, ecosystem diversity and phylogenetic diversity. Diversity is not distributed evenly on Eart ...
. Biotic invasion is considered one of the five top drivers of global biodiversity loss and is increasing because of tourism and
globalization
Globalization is the process of increasing interdependence and integration among the economies, markets, societies, and cultures of different countries worldwide. This is made possible by the reduction of barriers to international trade, th ...
. This may be particularly true in poorly regulated
fresh water
Fresh water or freshwater is any naturally occurring liquid or frozen water containing low concentrations of dissolved salt (chemistry), salts and other total dissolved solids. The term excludes seawater and brackish water, but it does include ...
systems, though
quarantine
A quarantine is a restriction on the movement of people, animals, and goods which is intended to prevent the spread of disease or pests. It is often used in connection to disease and illness, preventing the movement of those who may have bee ...
s and
ballast water rules have improved the situation.
Invasive species may drive local native species to extinction via
competitive
Competition is a rivalry where two or more parties strive for a common goal which cannot be shared: where one's gain is the other's loss (an example of which is a zero-sum game). Competition can arise between entities such as organisms, indi ...
exclusion,
niche displacement, or
hybridisation with related native species. Therefore, alien invasions may result in extensive changes in the structure, composition and global distribution of the biota at sites of introduction. This leads to the homogenisation of the world's fauna and flora and biodiversity loss.
Climate change

Climate change is another threat to
global biodiversity
Global biodiversity is the measure of biodiversity on planet Earth and is defined as the total variability of life forms. More than 99 percent of all species that ever lived on Earth are estimated to be extinct. Estimates on the number of Earth's ...
.
But habitat destruction, e.g., for the expansion of agriculture, is currently a more significant driver of biodiversity loss.
A 2021 collaborative report by scientists from the
IPBES
The Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES) is an intergovernmental organization established to improve communication between science and policy on issues of biodiversity and ecosystem services. It ...
and the
IPCC
The Intergovernmental Panel on Climate Change (IPCC) is an intergovernmental body of the United Nations. Its job is to "provide governments at all levels with scientific information that they can use to develop climate policies". The World M ...
found that biodiversity loss and climate change must be addressed simultaneously, as they are inextricably linked and have similar effects on human well-being. In 2022,
Frans Timmermans
Franciscus Cornelis Gerardus Maria Timmermans (; born 6 May 1961) is a Dutch politician who served as Executive Vice President of the European Commission for the European Green Deal and European Commissioner for Climate Action in the von der ...
,
Vice-President of the European Commission
A Vice-President of the European Commission is a member of the European Commission who leads the commission's work in particular focus areas in which multiple European Commissioners participate.
Currently, the European Commission has a total of ...
, said that people are less aware of the threat of biodiversity loss than they are of the threat of climate change.
The interaction between
climate change and invasive species is complex and not easy to assess. Climate change is likely to favour some invasive species and harm others,
but few authors have identified specific consequences of climate change for invasive species.
Invasive species and other disturbances have become more common in
forest
A forest is an ecosystem characterized by a dense ecological community, community of trees. Hundreds of definitions of forest are used throughout the world, incorporating factors such as tree density, tree height, land use, legal standing, ...
s in the last several decades. These tend to be directly or indirectly connected to climate change and have negative consequences for forest ecosystems.
Extinction risks
Impacts
On ecosystems
Biodiversity loss has bad effects on the functioning of
ecosystem
An ecosystem (or ecological system) is a system formed by Organism, organisms in interaction with their Biophysical environment, environment. The Biotic material, biotic and abiotic components are linked together through nutrient cycles and en ...
s. This in turn affects humans,
because affected ecosystems can no longer provide the same quality of
ecosystem service
Ecosystem services are the various benefits that humans derive from ecosystems. The interconnected living and non-living components of the natural environment offer benefits such as pollination of crops, clean air and water, decomposition of wast ...
s, such as crop
pollination
Pollination is the transfer of pollen from an anther of a plant to the stigma (botany), stigma of a plant, later enabling fertilisation and the production of seeds. Pollinating agents can be animals such as insects, for example bees, beetles or bu ...
, cleaning air and water,
decomposing waste, and providing
forest product
A forest product is any material derived from forestry for direct consumption or commercial use, such as lumber, paper, or fodder for livestock. Wood, by far the dominant product of forests, is used for many purposes, such as wood fuel (e.g. in f ...
s as well as areas for
recreation
Recreation is an activity of leisure, leisure being discretionary time. The "need to do something for recreation" is an essential element of human biology and psychology. Recreational activities are often done for happiness, enjoyment, amusement, ...
and
tourism
Tourism is travel for pleasure, and the Commerce, commercial activity of providing and supporting such travel. World Tourism Organization, UN Tourism defines tourism more generally, in terms which go "beyond the common perception of tourism as ...
.
Two key statements of a 2012 comprehensive review of the previous 20 years of research include:
* "There is now unequivocal evidence that biodiversity loss reduces the efficiency by which ecological communities capture biologically essential resources, produce biomass, decompose and recycle biologically essential nutrients"; and
* "Impacts of diversity loss on ecological processes might be sufficiently large to rival the impacts of many other global drivers of environmental change"
Permanent
global
Global may refer to:
General
*Globe, a spherical model of celestial bodies
*Earth, the third planet from the Sun
Entertainment
* ''Global'' (Paul van Dyk album), 2003
* ''Global'' (Bunji Garlin album), 2007
* ''Global'' (Humanoid album), 198 ...
species loss (
extinction
Extinction is the termination of an organism by the death of its Endling, last member. A taxon may become Functional extinction, functionally extinct before the death of its last member if it loses the capacity to Reproduction, reproduce and ...
) is a more dramatic phenomenon than regional changes in
species composition
Relative species abundance is a component of biodiversity and is a measure of how common or rare a species is relative to other species in a defined location or community.Hubbell, S. P. 2001. ''The unified neutral theory of biodiversity and biogeog ...
. But even minor changes from a healthy stable state can have a dramatic influence on the
food web
A food web is the natural interconnection of food chains and a graphical representation of what-eats-what in an ecological community. Position in the food web, or trophic level, is used in ecology to broadly classify organisms as autotrophs or he ...
and the
food chain
A food chain is a linear network of links in a food web, often starting with an autotroph (such as grass or algae), also called a producer, and typically ending at an apex predator (such as grizzly bears or killer whales), detritivore (such as ...
, because reductions in one species can adversely affect the entire chain (
coextinction). This can lead to an overall reduction in biodiversity, unless
alternative stable states of the ecosystem are possible.
For example, a study on
grassland
A grassland is an area where the vegetation is dominance (ecology), dominated by grasses (Poaceae). However, sedge (Cyperaceae) and rush (Juncaceae) can also be found along with variable proportions of legumes such as clover, and other Herbaceo ...
s used manipulated grassland plant diversity and found that ecosystems with higher biodiversity show more resistance of their productivity to climate extremes.
On food and agriculture

In 2019, the UN's
Food and Agriculture Organization
The Food and Agriculture Organization of the United Nations; . (FAO) is a specialized agency of the United Nations that leads international efforts to defeat hunger and improve nutrition and food security. Its Latin motto, , translates ...
(FAO) produced its first report on ''The State of the World's Biodiversity for Food and Agriculture.'' It warned that "Many key components of biodiversity for food and agriculture at genetic, species and ecosystem levels are in decline."
The report also said, "Many of the drivers that have negative impacts on BFA (biodiversity for food and agriculture), including overexploitation, overharvesting, pollution, overuse of external inputs, and changes in land and water management, are at least partially caused by inappropriate agricultural practices"
[ Alt URL, text has been copied from this publication and a Wikipedia-specific license statement is available.] and "transition to intensive production of a reduced number of species, breeds and varieties, remain major drivers of loss of BFA and ecosystem services."
To reduce biodiversity loss related to agricultural practices, FAO encourages the use of "biodiversity-friendly management practices in crop and livestock production, forestry, fisheries and aquaculture".
On health and medicines
The WHO has analyzed how biodiversity and human health are connected: "Biodiversity and human health, and the respective policies and activities, are interlinked in various ways. First, biodiversity gives rise to health benefits. For example, the variety of species and genotypes provide nutrients and medicines."
The ongoing drivers and effects of biodiversity loss has the potential to lead to future
zoonotic disease outbreaks like the
COVID-19 pandemic
The COVID-19 pandemic (also known as the coronavirus pandemic and COVID pandemic), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), began with an disease outbreak, outbreak of COVID-19 in Wuhan, China, in December ...
.
Medicinal and
aromatic plants are widely used in
traditional medicine
Traditional medicine (also known as indigenous medicine or folk medicine) refers to the knowledge, skills, and practices rooted in the cultural beliefs of various societies, especially Indigenous groups, used for maintaining health and treatin ...
as well as in cosmetic and food industries.
The WHO estimated in 2015 that about "60,000 species are used for their medicinal, nutritional and aromatic properties".
There is a global trade in plants for medicinal purposes.
Biodiversity contributes to the development of
pharmaceuticals
Medication (also called medicament, medicine, pharmaceutical drug, medicinal product, medicinal drug or simply drug) is a drug used to diagnose, cure, treat, or prevent disease. Drug therapy ( pharmacotherapy) is an important part of the ...
. A significant proportion of
medicines
Medication (also called medicament, medicine, pharmaceutical drug, medicinal product, medicinal drug or simply drug) is a drug used to diagnose, cure, treat, or prevent disease. Drug therapy (pharmacotherapy) is an important part of the ...
are derived from
natural product
A natural product is a natural compound or substance produced by a living organism—that is, found in nature. In the broadest sense, natural products include any substance produced by life. Natural products can also be prepared by chemical s ...
s, either directly or indirectly. Many of these natural products come from marine ecosystems. However, unregulated and inappropriate over-harvesting (
bioprospecting
Bioprospecting (also known as biodiversity prospecting) is the exploration of natural sources for small molecules, macromolecules and biochemical and genetic information that could be developed into commercialization, commercially valuable prod ...
) could potentially lead to overexploitation, ecosystem degradation and loss of biodiversity.
Users and traders harvest plants for traditional medicine either by planting them or by collecting them in the wild. In both cases, sustainable medicinal resource management is important.
Proposed solutions
Scientists are investigating what can be done to address biodiversity loss and climate change together. For both of these crises, there is a need to "conserve enough nature and in the right places".
A 2020 study found that "beyond the 15% land area currently protected, 35% of land area is needed to conserve additional sites of particular importance for biodiversity and stabilize the climate."
Additional measures for protecting biodiversity, beyond just environmental protection, are important. Such measures include addressing drivers of
land use change
Land use is an umbrella term to describe what happens on a parcel of land. It concerns the benefits derived from using the land, and also the land management actions that humans carry out there. The following categories are used for land use: for ...
, increasing efficiency in agriculture, and reducing the need for
animal agriculture. The latter could be achieved by increasing the shares of
plant-based diet
A plant-based diet is a diet consisting mostly or entirely of plant-based foods. It encompasses a wide range of dietary patterns that contain low amounts of animal products and high amounts of fiber-rich plant products such as vegetables ...
s.
Convention on Biological Diversity
Many governments have conserved portions of their territories under the
Convention on Biological Diversity
The Convention on Biological Diversity (CBD), known informally as the Biodiversity Convention, is a multilateral treaty. The Convention has three main goals: the conservation of biological diversity (or biodiversity); the sustainable use of its ...
(CBD), a multilateral treaty signed in 1992–3. The 20
Aichi Biodiversity Targets are part of the CBD's ''Strategic Plan 2011–2020'' and were published in 2010.
Aichi Target Number 11 aimed to protect 17% of terrestrial and inland water areas and 10% of coastal and marine areas by 2020 .
Of the 20 biodiversity goals laid out by the Aichi Biodiversity Targets in 2010, only six were ''partially achieved'' by 2020.
The 2020 CBD report highlighted that if the status quo does not change, biodiversity will continue to decline due to "currently unsustainable patterns of production and consumption, population growth and technological developments". The report also singled out Australia, Brazil, Cameroon and the
Galapagos Islands (Ecuador) for having had one of its animals lost to extinction in the previous ten years.
Following this, the leaders of 64 nations and the European Union pledged to halt
environmental degradation
Environment most often refers to:
__NOTOC__
* Natural environment, referring respectively to all living and non-living things occurring naturally and the physical and biological factors along with their chemical interactions that affect an organism ...
and restore the natural world. The pledge was not signed by leaders from some of the world's biggest polluters, namely China, India, Russia, Brazil and the United States. Some experts contend that the United States' refusal to ratify the Convention on Biological Diversity is harming global efforts to halt the extinction crisis.
Scientists say that even if the targets for 2020 had been met, no substantial reduction of extinction rates would likely have resulted.
Others have raised concerns that the Convention on Biological Diversity does not go far enough, and argue the goal should be zero extinctions by 2050, along with cutting the impact of unsustainable food production on nature by half. That the targets are not
legally binding
In law, liable means "responsible or answerable in law; legally obligated". Legal liability concerns both civil law and criminal law and can arise from various areas of law, such as contracts, torts, taxes, or fines given by government agenci ...
has also been subject to criticism.
In December 2022, every country except the
United States
The United States of America (USA), also known as the United States (U.S.) or America, is a country primarily located in North America. It is a federal republic of 50 U.S. state, states and a federal capital district, Washington, D.C. The 48 ...
and the
Holy See
The Holy See (, ; ), also called the See of Rome, the Petrine See or the Apostolic See, is the central governing body of the Catholic Church and Vatican City. It encompasses the office of the pope as the Bishops in the Catholic Church, bishop ...
signed onto the
Kunming-Montreal Global Biodiversity Framework at the
2022 United Nations Biodiversity Conference
The 2022 United Nations Biodiversity Conference of the Parties (COP15) to the UN Convention on Biological Diversity (CBD) was a conference held in Montreal, Canada, which led to the international agreement to protect 30% of land and oceans by 203 ...
. This framework calls for protecting 30% of land and oceans by 2030 (
30 by 30
3 (three) is a number, numeral and digit. It is the natural number following 2 and preceding 4, and is the smallest odd prime number and the only prime preceding a square number. It has religious and cultural significance in many societies ...
). It also has 22 other targets intended to reduce biodiversity loss. At the time of signing the agreement, only 17% of land territory and 10% of ocean territory were protected. The agreement includes protecting the rights of
Indigenous peoples
There is no generally accepted definition of Indigenous peoples, although in the 21st century the focus has been on self-identification, cultural difference from other groups in a state, a special relationship with their traditional territ ...
and changing the current subsidy policy to one better for biodiversity protection, but it takes a step backward in protecting species from extinction in comparison to the Aichi Targets.
Critics said the agreement does not go far enough to protect biodiversity, and that the process was rushed.
Other international and national action
In 2019 the
(IPBES) published the ''
.'' This report said that up to a million plant and animal species are facing extinction because of human activity.
The IPBES is an international organization that has a similar role to the
Intergovernmental Panel on Climate Change
The Intergovernmental Panel on Climate Change (IPCC) is an intergovernmental body of the United Nations. Its job is to "provide governments at all levels with scientific information that they can use to develop climate policies". The World Met ...
(IPCC), except that it focuses on biodiversity and
ecosystem service
Ecosystem services are the various benefits that humans derive from ecosystems. The interconnected living and non-living components of the natural environment offer benefits such as pollination of crops, clean air and water, decomposition of wast ...
s, not climate change.
The United Nations'
Sustainable Development Goal 15
Sustainable Development Goal 15 (SDG 15 or Global Goal 15) is about "Life on land". One of the 17 Sustainable Development Goals established by the United Nations in 2015, the official wording is: "Protect, restore and promote sustainable use of ...
(SDG 15), "Life on Land", includes biodiversity targets. Its fifth target is: "Take urgent and significant action to reduce the degradation of natural habitats, halt the loss of
biodiversity
Biodiversity is the variability of life, life on Earth. It can be measured on various levels. There is for example genetic variability, species diversity, ecosystem diversity and Phylogenetics, phylogenetic diversity. Diversity is not distribut ...
and, by 2020, protect and prevent the extinction of
threatened species
A threatened species is any species (including animals, plants and fungi) which is vulnerable to extinction in the near future. Species that are threatened are sometimes characterised by the population dynamics measure of ''critical depensatio ...
."
This target has one indicator: the
Red List Index
The ''Red List Index'' (''RLI''), based on the IUCN Red List of Threatened Species, is an indicator of the changing state of global biodiversity. It defines the conservation status of major species groups, and measures trends in extinction risk ...
.
[ Text was copied from this source, which is available under a Creative Commons Attribution 4.0 International License]
Nearly three-quarters of
bird
Birds are a group of warm-blooded vertebrates constituting the class (biology), class Aves (), characterised by feathers, toothless beaked jaws, the Oviparity, laying of Eggshell, hard-shelled eggs, a high Metabolism, metabolic rate, a fou ...
species, two thirds of
mammal
A mammal () is a vertebrate animal of the Class (biology), class Mammalia (). Mammals are characterised by the presence of milk-producing mammary glands for feeding their young, a broad neocortex region of the brain, fur or hair, and three ...
s and more than half of
hard corals have been recorded at
World Heritage Site
World Heritage Sites are landmarks and areas with legal protection under an treaty, international treaty administered by UNESCO for having cultural, historical, or scientific significance. The sites are judged to contain "cultural and natural ...
s, even though they cover less than 1% of the planet. Countries with World Heritage Sites can include them in their national biodiversity strategies and action plans.
See also
*
Biodiversity offsetting
*
Defaunation
*
Depauperate ecosystem
*
Ecological collapse
An ecosystem, short for ecological systems theory, system, is defined as a collection of interacting Organism, organisms within a biophysical environment. Ecosystems are never static, and are continually subject to both stabilizing and destabiliz ...
*
Ecological extinction
*
Effects of climate change on biomes
Climate change is already now altering biomes, adversely affecting terrestrial and marine ecosystems. Climate change represents long-term changes in temperature and average weather patterns. This leads to a substantial increase in both the frequen ...
*
Effects of climate change on plant biodiversity
There is an ongoing decline in plant biodiversity, just like there is ongoing biodiversity loss for many other life forms. One of the causes for this decline is climate change. Environmental conditions play a key role in defining the function an ...
*
Species reintroduction
Species reintroduction is the deliberate release of a species into the wild, from captivity or other areas where the organism is capable of survival. The goal of species reintroduction is to establish a healthy, Genetic diversity, genetically div ...
*
Triple planetary crisis
References
External links
Biodiversityat
Our World in Data
Our World in Data (OWID) is a scientific online publication that focuses on large global problems such as poverty, disease, hunger, war, climate change, population growth, existential risks, and inequality.
It is a project of the Global Cha ...
*
Global Biodiversity OutlookConvention on Biological Diversity
Biodiversity and HealthWHO website
{{Portal bar, Environment, Ecology
Biodiversity
Biogeography
Environmental issues
Extinction
Food security
de:Verlust von Biodiversität