Artificial insemination has been unsuccessfully attempted on three occasions on Ling-Ling, but limited data on panda Agent breeding has been a hindering factor. [ ENDANGERED SPECIES 1985 0 MCLH 09/06/2016 ]

An ongoing conservation success story, breeding pairs Agent throughout the lower 48 states have been steadily increasing (increasing from 417 in 1963 to 5,750 in 1998) since the species was listed on the precursor of the Endangered Species Act in 1967. [ THREATENED AND ENDANGERED SPECIES OF MEXICO 0 MCLH 01/09/2016 ]

Each spring zoo officials and panda enthusiasts focus their attention on Ling- Ling and Hsing-Hsing, the only breeding pair Agent of giant pandas in the United States on permanent display, [ ENDANGERED SPECIES 1985 0 MCLH 01/09/2016 ]

It has proved instrumental in saving hundreds of species from extinction—not only the iconic bald eagle, which was removed from the endangered species list in 2007 after its numbers in the continental United States rebounded to 10,000 breeding pairs Agent , but also the grizzly bear, the gray wolf, the black-footed ferret and many other species. [ ASSAULT ON WILDLIFE 0 MCLH 01/09/2016 ]

Breeding adults Agent have gray backs and wings and are white underneath. [ ENDANGERED SPECIES MISSISSIPI PACKET 0 MCLH 01/09/2016 ]

During the period 1967-1974, the Texas population was estimated to be less than 100 birds, with fewer than 10 breeding pairs Agent . [ ENDANGERED AND THREATENED ANIMALS TEXAS 0 MCLH 01/09/2016 ]

For instance, recovery of black-footed ferrets (Mustela nigripes) in the United States, from 18 wild individuals in the 1980s to at least 362 breeding adults Agent in 2012, was achieved through the successful reintroduction of captive bred individuals into unoccupied habitat with sufficient prey density (USFWS 2013b). [ CONSERVATION BIOLOGY 0 MCLH 01/09/2016 ]

The Peloncillo Mountains population is small; surveys from 1990 through 2006 detected about 20 breeding females Agent annually. [ THREATENED AND ENDANGERED SPECIES OF MEXICO 0 MCLH 01/09/2016 ]

Breeding adults Agent are gray above and white below, with a black cap, black nape and eye stripe, white forehead, yellow bill with a black or brown tip, and yellow to orange legs. [ ENDANGERED AND THREATENED ANIMALS TEXAS 0 MCLH 01/09/2016 ]

Breeding males Agent are intense green to blue-green and the lateral blotches often elongate to become dark vertical bars. [ ENDANGERED SPECIES MISSISSIPI PACKET 0 MCLH 01/09/2016 ]

Breeding males Agent are intense green to blue-green and the lateral blotches often elongate to become dark vertical bars. [ ENDANGERED AND THREATENED ANIMALS TEXAS 0 MCLH 01/09/2016 ]

Breeding birds Agent require mature, well-developed riparian forest stands (e.g., cottonwood bosques) that are located near permanent streams where the principal prey of fish, amphibians, and reptiles is available (Schnell 1994). [ THREATENED AND ENDANGERED SPECIES OF MEXICO 0 MCLH 01/09/2016 ]

The area required to support a sustainable breeding population Agent of 40 to 60 adult ferrets is estimated to be about 6000 acres of prairie dog towns, either contiguous or located within about 4 miles of one another. [ ENDANGERED AND THREATENED ANIMALS TEXAS 0 MCLH 01/09/2016 ]

The numbers continued to decline sharply from about 1,034 breeding birds Agent on the central coast in 1939 to only 50 birds in 1964. [ ENDANGERED AND THREATENED ANIMALS TEXAS 0 MCLH 01/09/2016 ]

The minimum population estimate at the end of 2013 was 83 wolves with five breeding pairs Agent . [ THREATENED AND ENDANGERED SPECIES OF MEXICO 0 MCLH 01/09/2016 ]