Frogs, toads, and salamanders are disappearing because of habitat loss, water and air pollution, climate change, ultraviolet light exposure, introduced exotic species, and disease.
Because of their sensitivity to environmental changes, vanishing amphibians should be viewed as the canary in the global coal mine, signaling subtle yet radical ecosystem changes that could ultimately claim many other species, including humans. BIRDS Birds occur in nearly every habitat on the planet and are often the most visible and familiar wildlife to people across the globe. As such, they provide an important bellwether for tracking changes to the biosphere. Declining bird populations across most to all habitats confirm that profound changes are occurring on our planet in response to human activities.
A report on the state of birds in the United States found that 31 percent of the species in the country are of conservation concern [ 7 ]. Habitat loss and degradation have caused most of the bird declines, but the impacts of invasive species and capture by collectors play a big role, too. FISH Increasing demand for water, the damming of rivers throughout the world, the dumping and accumulation of various pollutants, and invasive species make aquatic ecosystems some of the most threatened on the planet; thus, it's not surprising that there are many fish species that are endangered in both freshwater and marine habitats.
The American Fisheries Society identified species of freshwater or anadromous fish in North America as being imperiled, amounting to 39 percent of all such fish on the continent [ 8 ]. In North American marine waters, at least 82 fish species are imperiled. Across the globe, 1, species of fish — 21 percent of all fish species evaluated — were deemed at risk of extinction by the IUCN in , including more than a third of sharks and rays.
Of the 1. Freshwater invertebrates are severely threatened by water pollution, groundwater withdrawal, and water projects, while a large number of invertebrates of notable scientific significance have become either endangered or extinct due to deforestation, especially because of the rapid destruction of tropical rainforests.
In the ocean, reef-building corals are declining at an alarming rate: 's first-ever comprehensive global assessment of these animals revealed that a third of reef-building corals are threatened. MAMMALS Perhaps one of the most striking elements of the present extinction crisis is the fact that the majority of our closest relatives — the primates — are severely endangered.
About 90 percent of primates — the group that contains monkeys, lemurs, lorids, galagos, tarsiers, and apes as well as humans — live in tropical forests, which are fast disappearing. The IUCN estimates that almost 50 percent of the world's primate species are at risk of extinction. Former president Andry Rajoelina, whose previous tenure was marked by a dramatic increase in illegal logging, deforestation and biodiversity loss , was reelected last month, although as of press time the election remains mired in protests and accusations of fraud.
Johnson expects funding to remain an issue in , as will further attacks against the Endangered Species Act. Others echoed those thoughts and fears about the ESA. Many of our experts expressed cautious optimism about these new government representatives.
Roads to Ruin, But a Push to Preserve. But outside of Washington, things are speeding up. New road and infrastructure projects, many backed by Chinese investment, are currently being carved into critical habitats in Indonesia, Africa, the Amazon and other regions. One of the most notorious projects is a gigantic hydroelectric dam that could wipe out the newly discovered Tapanuli orangutan Pongo tapanuliensis in Sumatra.
Meanwhile, a similar—if not even more extensive—proliferation of illegal roads is being constructed around the world by loggers, miners, poachers and other extractive industries. These activities threaten everything from elephants and tigers to insects and rare plants. Right now he and his team pore over satellite images by hand, looking for signs of new disturbance—not an easy prospect when images vary by surface, shadowing and other factors.
Laurance has issued a call for help to develop a software tool to automate the road-discovery process. Without that, conservation—and species—will lose ground every day. Many of the experts we spoke with expressed hope that the tight deadline will result in some good, quick land and water protection that could protect countless species, but cautioned that these efforts should be watched carefully to make sure they truly protect key habitats and that they offer connectivity between disparate species populations.
The oceans will also be a big part of the Aichi targets. A Host of Other Issues. Here are a few more factors predicted to play a big role in Habitat loss is a process of environmental change in which a natural habitat is rendered functionally unable to support the species present.
This process may be natural or unnatural, and may be caused by habitat fragmentation, geological processes, climate change, or human activities such as the introduction of invasive species or ecosystem nutrient depletion.
In the process of habitat destruction, the organisms that previously used the site are displaced or destroyed, reducing biodiversity. Biodiversity loss in Sumatra : a One sub-species of orangutan is found only in the rain forests of Borneo, while the other sub-species of orangutan is found only in the rain forests of Sumatra.
These animals are examples of the exceptional biodiversity of c the islands of Sumatra and Borneo. Other species include the b Sumatran tiger and the d Sumatran elephant, both of which are critically endangered. Human destruction of habitats has accelerated greatly in the latter half of the twentieth century.
Natural habitats are often destroyed through human activity for the purpose of harvesting natural resources for industry production and urbanization. Clearing habitats for agriculture, for example, is the principal cause of habitat destruction. Other important causes of habitat destruction include mining, logging, and urban sprawl.
Habitat destruction is currently ranked as the primary cause of species extinction worldwide. Consider the exceptional biodiversity of Sumatra. The neighboring island of Borneo, home to the other sub-species of orangutan, has lost a similar area of forest, and forest loss continues in protected areas. The orangutan in Borneo is listed as endangered by the International Union for Conservation of Nature IUCN , but it is simply the most visible of thousands of species that will not survive the disappearance of the forests of Borneo.
The forests are being removed for their timber, and to clear space for plantations of palm oil, an oil used in Europe for many items including food products, cosmetics, and biodiesel. A five-year estimate of global forest cover loss for the years — was 3. In the humid tropics where forest loss is primarily from timber extraction, , km 2 was lost out of a global total of 11,, km 2 or 2. In the tropics, these losses also represent the extinction of species because of high levels of endemism.
In temperate and boreal regions, forest area is gradually increasing with the exception of Siberia , but deforestation in the tropics is of major concern. Sustainable practices, which preserve environments for long-term maintenance and well-being, can help preserve habitats and ecosystems for greater biodiversity.
Sustainability is a concept that describes how biological systems remain diverse and productive over time. Long-lived and healthy wetlands and forests are examples of sustainable biological systems. For humans, sustainability is the potential for long-term maintenance of well-being, which has ecological, economic, political, and cultural dimensions.
One approach is environmental management, which is based largely on information gained from earth science, environmental science, and conservation biology. A second approach is management of human consumption of resources, which is based largely on information gained from economics. A third, more recent, approach adds cultural and political concerns into the sustainability matrix.
Loss of biodiversity stems largely from the habitat loss and fragmentation produced by human appropriation of land for development, forestry and agriculture as natural capital is progressively converted to human-made capital. At the local human scale, sustainability benefits accrue from the creation of green cities and sustainable parks and gardens. Similarly, environmental problems associated with industrial agriculture and agribusiness are now being addressed through such movements as sustainable agriculture, organic farming, and more-sustainable business practices.
Overharvesting threatens biodiversity by degrading ecosystems and eliminating species of plants, animals, and other organisms.
Overharvesting, also called overexploitation, refers to harvesting a renewable resource to the point of diminishing returns. Ecologists use the term to describe populations that are harvested at a rate that is unsustainable, given their natural rates of mortality and capacities for reproduction. The term applies to natural resources such as wild medicinal plants, grazing pastures, game animals, fish stocks, forests, and water aquifers.
Sustained overharvesting can lead to the destruction of the resource, and is one of the five main activities — along with pollution, introduced species, habitat fragmentation, and habitat destruction — that threaten global biodiversity today.
All living organisms require resources to survive. Overharvesting these resources for extended periods of time can deplete natural resources to the point where they are unable to recover within a short time frame.
Humans have always harvested food and other resources they have needed to survive; however, human populations, historically, were small and methods of collection limited to small quantities. Exponential increase in human population, expanding markets, and increasing demand, combined with improved access and techniques for capture, are causing the exploitation of many species beyond sustainable levels. In addition to this, we need to be mindful of tackling increased urbanization, rising temperatures, and ecotourism, which are negatively contributing and fueling to affect wildlife.
Dramatic urbanization has led species living in urban environments to develop differently from their non-urban counterparts. In the last 50 years, the global average temperature has risen at times, having dangerous effects on wildlife populations. Although ecotourism can help to raise awareness of wildlife, it has severe adverse effects like chronic stress and decreased immune systems [2].
The scale of the problem is multifaceted; as individuals, we can strive to lower the carbon footprint and urge governments to help make our countries greener.
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