THE EXTINCTION CRISIS

It's frightening but true: Our planet is now in the midst of its sixth mass extinction

of plants and animals — the sixth wave of extinctions in the past half-billion years. We’re currently experiencing the worst spate of species die-offs since the loss of the dinosaurs 65 million years ago. Although extinction is a natural phenomenon, it occurs at a natural “background” rate of about one to five species per year. Scientists estimate we’re now losing species at 1,000 to 10,000 times the background rate, with literally dozens going extinct every day. It could be a scary future indeed, with as many as 30 to 50 percent of all species possibly heading toward extinction by mid-century.

Unlike past mass extinctions, caused by events like asteroid strikes, volcanic eruptions, and natural climate shifts, the current crisis is almost entirely caused by us — humans.
In fact, 99 percent of currently threatened species are at risk from human activities, primarily those driving habitat loss, introduction of exotic species, and global warming. Because the rate of change in our biosphere is increasing, and because every species’ extinction potentially leads to the extinction of others bound to that species in a complex ecological web, numbers of extinctions are likely to snowball in the coming decades as ecosystems unravel.

 

Species diversity ensures ecosystem resilience, giving ecological communities the scope they need to withstand stress. Thus while conservationists often justifiably focus their efforts on species-rich ecosystems like rainforests and coral reefs — which have a lot to lose — a comprehensive strategy for saving biodiversity must also include habitat types with fewer species, like grasslands, tundra, and polar seas — for which any loss could be irreversibly devastating. And while much concern over extinction focuses on globally lost species, most of biodiversity’s benefits take place at a local level, and conserving local populations is the only way to ensure genetic diversity critical for a species’ long-term survival.

Nobody really knows how many species are in danger of becoming extinct. Noted conservation scientist David Wilcove estimates that there are 14,000 to 35,000 endangered species, right now, in the United States alone. What’s clear is that many thousands of species are at risk of disappearing forever in the coming decades.

AMPHIBIANS

No group of animals has a higher rate of endangerment than amphibians. Scientists estimate that a third or more of all the roughly 6,300 known species of amphibians are at risk of extinction.The current amphibian extinction rate may range from 25,039 to 45,474 times the background extinction rate .
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.

 

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 700 species of freshwater or anadromous fish in North America as being imperiled, amounting to 39 percent of all such fish on the continent. In North American marine waters, at least 82 fish species are imperiled. Across the globe, 1,851 species of fish —  21 percent of all fish species evaluated —  were deemed at risk of extinction by the IUCN in 2010, including more than a third of sharks and rays.

INVERTEBRATES

Invertebrates, from butterflies to mollusks to earthworms to corals, are vastly diverse — and though no one knows just how many invertebrate species exist, they’re estimated to account for about 97 percent of the total species of animals on Earth. Of the 1.3 million known invertebrate species, about 30 percent of the species are evaluated at risk of extinction. Freshwater invertebrates are severely threatened by water pollution, groundwater withdrawal, and water projects. In the ocean, reef-building corals are declining at an alarming rate: 2008’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. Overall, the IUCN estimates that half the globe’s 5,491 known mammals are declining in population and a fifth are clearly at risk of disappearing forever. In addition to primates, marine mammals — including several species of whales, dolphins, and porpoises — are among those mammals slipping most quickly toward extinction.

PLANTS

Through photosynthesis, plants provide the oxygen we breathe and the food we eat and are thus the foundation of most life on Earth. They’re also the source of a majority of medicines in use today. Of the more than 300,000 known species of plants, the IUCN has evaluated only 12,914 species, finding that about 68 percent of evaluated plant species are threatened with extinction.

REPTILES

Globally, 21 percent of the total evaluated reptiles in the world are deemed endangered or vulnerable to extinction by the IUCN — 594 species — while in the United States, 32 reptile species are at risk, about 9 percent of the total. The main threats to reptiles are habitat destruction and the invasion of nonnative species, which prey on reptiles and compete with them for habitat and food. 
An example of this is the Burmese python which has invaded the Everglades in Florida. It is believed to have started with the release of the snakes by pet owners into the swamps. The snakes were once popular as pets but they grow extremely large ( one of the largest snakes on earth ) and become difficult to keep safely in a home environment. Since the pythons originated in Asia, they have no natural predators in Florida and are reproducing rapidly throughout South Florida. They are consuming native species and depleting food sources for native reptiles.

All of the extinctions with few exceptions have been directly or indirectly caused by mankind's  interference with nature or pollution of the environment. The solution is easy-peasy... just 'STOP IT'.