The U.S. Fish and Wildlife Service has performed extensive research covering the cougar's traditional U.S. and Canadian habitats. They've determined there the animals likely haven't been in existence for over 70 years. It's been suggested that the cougar sub-species be removed from the endangered list and declared extinct.
The large felines now occupying the regions once dominated by the eastern variety migrated there from the western United States and Florida. The demise of the eastern cougar was first acknowledged in 1973, the year it was placed on the list of endangered species. Troubles for the animal are believed to have begun in the 1800s. At the time they were plentiful, and thus commonly shot by settlers wanting to protect themselves, their families, and their livestock. That, combined with the depletion of their primary source of food, the white-tailed deer, led to a significant population reduction.
The last eastern cougar sighting is believed to have occurred in 1938.
Currently endangered species:
Endangered species around the world
Eastern Cougar believed to be extinct, probably has been for over 70 years
Sumatran orang-utan Anita, 23, and her baby Atina, 1, eat a fruit at the unveiling of their new habitat in the Singapore Zoo July 31, 2007. The Sumatran orang utans are categorised as critically endangered with their population standing at approximately 7500 in the wild, according to Singapore zoological officials.
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Baby pygmy hippopotamus 'Lani' walks on a path on May 17, 2014 at the Basel Zoo. Lani is one around 135 pygmy hippopotamuses in the European Endangered Species Program.
(Photo by Fabrice Coffrini via Getty Images)
Pileated gibbonon the tree in real nature at Khaoyai national park, Thailand.
(kajornyot via Getty Images)
Two sand cats born on April 15, 2008 are pictured on April, 25, 2008 at the Amneville's zoo, eastern France. Sand cats are one of the smallest of the wild cats, ranging from Sahara in North Africa to the arid regions of Iran and Pakistan in West and South Asia.
(Photo by Johanna Leguerre via AFP/Getty Images)
This Mountain Pygmy Possum is part of a breeding program at Healesville Sanctuary, 10 March 2007.
(Photo by Andrew De La Rue/The AGE/Fairfax Media via Getty Images)
Wild Black-footed Ferret, Mustela nigripes, also known as the American polecat or Prairie Dog Hunter, Grasslands National Park, Saskatchewan, Canada, one of 35 reintroduced back into Canada in 2009.
(John E Marriott via Getty Images)
Koola, an 18-year-old western lowland gorilla holds her newborn infant in her enclosure at Brookfield Zoo on November 6, 2013 in Brookfield, Illinois.
(Photo by Scott Olson/Getty Images)
WINCHESTER, UNITED KINGDOM - SEPTEMBER 01: Amur leopard cubs pictured enjoying their day at Marwell Zoo on September 1, 2016 in Winchester, England. THESE leopard cubs are only nine weeks old but already a media sensation. Two Amur leopard cubs made their first public appearance at Marwell zoo near Winchester this morning. The creatures are amongst the most endangered big cats in the world and these two young boys are part of a program to protect the leopard's future.
(Carolyn Dunford /Barcroft Images / Barcroft Media via Getty Images)
Axolotls are seen in a cage where scientists of the Biology Institute of the National Autonomous University of Mexico (UNAM) are reproducing them at an experimental canal of Xochimilco in Mexico City February 13, 2014. Scientists at UNAM's Biology Institute have warned the Axolotl (Ambystoma mexicanum) or Mexican salamander, could be at risk of extinction in the wild in five to 10 years as axolotl populations were declining in 2003. But a few canals in the southern Mexico City suburb of Xochimilco, the only waterways where some axolotls may still live, are threatened by pollution caused by the city's continuous expansion and the days of the species in the wild are numbered. The axolotl is now on the endangered species list of the Convention on International Trade in Endangered Species (CITES).
A greater bamboo lemur is seen in this picture released by Conservation International on July 22, 2008. Researchers in Madagascar have found critically endangered greater bamboo lemurs living far from the only other place they were known to exist, raising hopes for the survival of the species, experts said on Tuesday.
A Dendrobates leucomelas frog is pictured at a terrarium in Caracas November 30, 2015. Venezuelan frogs and toads are in critical danger due to climate change as rising temperatures complicate reproduction and spread a deadly fungus, say scientists, who liken the species to canaries in a coalmine warning of imminent danger. The survival of a group of nearly 20 frog and toad species, which top Venezuela's list of endangered species, may rest on a small group of academics in a Caracas laboratory attempting to recreate the amphibians' natural reproductive conditions. Picture taken on November 30, 2015.
(REUTERS/Carlos Garcia Rawlins)
Seven months old 'Nuan Nuan', a female giant panda cub, plays inside the panda enclosure at the National Zoo in Kuala Lumpur, Malaysia on April 8, 2016. Nuan Nuan, which means 'friendship' in Chinese, was named in a ceremony where her name was picked from almost 23.000 suggestions coming from the Malaysian public.
(Photo by Alexandra Radu/Anadolu Agency/Getty Images)
A handout photo dated March 21, 2013 shows a short-eared elephant shrew swinging on his new swing in the Wilhelmina in Stuttgart, Germany. Short-eared elephant shrews grow only 22 to 24 cm long; half of the length is made up by the tail. They live in Africa and can reach a speed of up to 20 km/h.
(Photo by Susanne Kern/DPA)
Owabi, a two-week-old monkey cub of the Cercopithecus roloway family, one of the 25 most endangered primate species in the world, is pictured with its mother, Nyaga, on August 2, 2012 at the zoo in Mulhouse, eastern France.
(Photo by Sebstien Bozon via AFP/Getty Images)
An employee poses with an Egyptian tortoise during a photo call for Whipsnade Zoo's annual stocktake in Dunstable, Bedfordshire, north of London, on January 7, 2014.
(Photo by Carl Court via AFP/Getty Images)
This picture taken on November 8, 2016 shows Andatu, a Sumatran rhino, one of the rarest large mammals on earth, at the Rhino Sanctuary at Way Kambas National Park in eastern Sumatra. There are no more than 100 left on the entire planet and Andatu -- a four-year old male -- is one of the last remaining hopes for the future of the species. He is part of a special breeding program at Way Kambas National Park in eastern Sumatra that is trying to save this critically endangered species from disappearing forever.
(GOH CHAI HIN/AFP/Getty Images)
A zoo keeper holds a baby Philippine crocodile during the annual weigh-in to record animals vital statistics at ZSL London Zoo in London on August 21, 2014.
(Photo by Carl Court via AFP/Getty Images)
The "Indian" or "Java" rhinoceros is listed as a critically endangered of extinction, this rare animal has only one horn which marks the main difference with the African type.
(Photo by Roberto Machado Noa/LightRocket via Getty Images)
A female Northern Bald Ibis, also referred to as Waldrapp, warms her nest while two fellows protect her at the zoo in St. Peter-Ording, Germany, on May 5, 2008.
(Photo by Carsten Rehder/DPA)
A critically endangered small tooth sawfish roams its new home at Oceanworld in Sydney on August 18, 2011. Measuring over 1.5 metres in length, sawfish have adapted to live in both salt and fresh water, while their long saw-like rostrum (nose) has evolved to expertly forage for food under the sandy ocean floor.
(Photo by Torsten Blackwood via AFP/Getty Images)
A giant soft-shell turtle which is considered a sacred symbol of Vietnamese independence is guided into a cage for a health check by handlers at Hoan Kiem lake in the heart of Hanoi. Thousands of onlookers cheered in central Hanoi on April 3, 2011 when rescuers captured for treatment the ailing and ancient giant turtle. Legend has it that the turtle is the guardian of a magical sword once used in the 15th century to drive out Chinese invaders. Concern has mounted in recent months over the health of the animal likely to be over 100 years old and one of the last of a critically endangered species -- it is one of only four Rafetus swinhoei turtles known to exist in the world.
(Photo by Vietnam News Agency via AFP/Getty Images)
A Hypsiboas crepitans frog is pictured at a terrarium in Caracas November 30, 2015. Venezuelan frogs and toads are in critical danger due to climate change as rising temperatures complicate reproduction and spread a deadly fungus, say scientists, who liken the species to canaries in a coalmine warning of imminent danger. The survival of a group of nearly 20 frog and toad species, which top Venezuela's list of endangered species, may rest on a small group of academics in a Caracas laboratory attempting to recreate the amphibians' natural reproductive conditions. Picture taken on November 30, 2015.
(REUTERS/Carlos Garcia Rawlins)
Ema Elsa, a nine-year-old Black Rhino, lies next to her newborn calf in their enclosure at Chester Zoo in Chester, northern England October 5, 2012. The female calf which is less than 48 hours old will join an international breeding program for the critically endangered species.
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