Under the Endangered Species Act (ESA), plant and animal species may be listed as either endangered or threatened. “Endangered” means a species is in danger of extinction throughout all or a significant portion of its range. “Threatened” means a species is likely to become endangered within the foreseeable future.
States have their own ESA-type laws, so species can have different Threatened/Endangered statuses at the federal and state levels. The USGS typically refers to the federal status unless otherwise noted.
"Imperiled" or "at risk" are not legal terms under ESA, but more biological terms. Generally speaking, they are animals and plants that are in decline and may be in danger of extinction. Those terms can include species that are at low populations and near extinction but still not legally protected under ESA.
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Are salmon endangered worldwide?
No, salmon are not endangered worldwide. For example, most populations in Alaska are healthy. Some populations in the Pacific Northwest are much healthier than others. These healthy populations usually occupy protected habitats such as the Hanford Reach on the Columbia River and streams of Olympic National Park. Learn more: Western Fisheries Research Center - Questions and Answers about Salmon
What is the threat from West Nile Virus (WNV) to endangered and threatened bird species?
This is an issue of great concern, as these populations are already struggling to survive in the current environment. If some of these species are more vulnerable to fatal WNV infection, WNV may ultimately lead to their extinction or significantly set back the progress of the recovery programs.
Where are salmon most endangered?
Certain populations of sockeye salmon, coho salmon, chinook salmon, and Atlantic salmon are listed as endangered. Sockeye salmon from the Snake River system are probably the most endangered salmon. Coho salmon in the lower Columbia River may already be extinct. Salmon are not endangered worldwide. For example, most populations in Alaska are healthy. Some populations in the Pacific Northwest are...
Why do animals and plants become endangered?
Although extinctions occur naturally, the current rate of plant and animal extinctions is much higher than the natural or historical rates. Habitat loss is the primary cause of higher extinction rates. Other causes include habitat changes, over-exploitation of wildlife for commercial purposes, the introduction of harmful nonnative species, pollution, and the spread of diseases.Learn more...
What species of bats are affected by White-nose Syndrome?
White-nose Syndrome mostly affects hibernating bats. More than half of the 47 bat species living in the United States and Canada hibernate to survive the winter. Twelve bat species, including two endangered species and one threatened species, have been confirmed with white-nose syndrome in North America. The causative fungus, Pseudogymnoascus destructans (Pd), has been found on an additional six...
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- FAQ
Are salmon endangered worldwide?
No, salmon are not endangered worldwide. For example, most populations in Alaska are healthy. Some populations in the Pacific Northwest are much healthier than others. These healthy populations usually occupy protected habitats such as the Hanford Reach on the Columbia River and streams of Olympic National Park. Learn more: Western Fisheries Research Center - Questions and Answers about Salmon
What is the threat from West Nile Virus (WNV) to endangered and threatened bird species?
This is an issue of great concern, as these populations are already struggling to survive in the current environment. If some of these species are more vulnerable to fatal WNV infection, WNV may ultimately lead to their extinction or significantly set back the progress of the recovery programs.
Where are salmon most endangered?
Certain populations of sockeye salmon, coho salmon, chinook salmon, and Atlantic salmon are listed as endangered. Sockeye salmon from the Snake River system are probably the most endangered salmon. Coho salmon in the lower Columbia River may already be extinct. Salmon are not endangered worldwide. For example, most populations in Alaska are healthy. Some populations in the Pacific Northwest are...
Why do animals and plants become endangered?
Although extinctions occur naturally, the current rate of plant and animal extinctions is much higher than the natural or historical rates. Habitat loss is the primary cause of higher extinction rates. Other causes include habitat changes, over-exploitation of wildlife for commercial purposes, the introduction of harmful nonnative species, pollution, and the spread of diseases.Learn more...
What species of bats are affected by White-nose Syndrome?
White-nose Syndrome mostly affects hibernating bats. More than half of the 47 bat species living in the United States and Canada hibernate to survive the winter. Twelve bat species, including two endangered species and one threatened species, have been confirmed with white-nose syndrome in North America. The causative fungus, Pseudogymnoascus destructans (Pd), has been found on an additional six...
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