The aplomado falcon once inhabited a vast historical range, extending from the southwestern U.S. to Argentina.  In the U.S., this included southeastern Arizona, southern New Mexico, and the Trans-Pecos and southern portions of Texas.

Populations of aplomado falcons began to decline in 1890, and by 1950 the bird was largely extirpated from its range north of the Mexican border (Hector, 1987).  The reasons for this are unclear, but likely factors include habitat loss, pesticides, collection of voucher specimens, and disease.

In 1986, the falcon was listed as endangered under the Endangered Species Act (Fed. Register 51 (37), February 25, 1986, pp.6686-6690).  In 1987, The Peregrine Fund (TPF), the Mexican government, and the United States Fish and Wildlife Service (USFWS) launched a cooperative program to restore the falcon to the U.S. and northern Mexico, with the primary goal of establishing a self-sustaining population of 60 breeding pairs in the U.S.

TPF, known for their expertise in restoring endangered birds, established a captive breeding program for the falcon.  In 1987 and 1988, TPF researchers surveyed suitable habitat in Mexico (Sandfort, 1994).  The researchers found 25 territories and located 15 active nests.  Nestlings were taken during both years to establish the captive breeding program (Mutch, 2007). 

The first reintroduction took place in Texas in 1993.  Since 1985 there have been over 1500 releases resulting in 50 known breeding pairs.  In 2006, there were 56 wild young fledged from 33 nests (TPF Operation Report).  From 2006 to 2008, TPF, the USFWS, along with several private and public land owners including Turner Enterprises Inc. on the Armendaris Ranch, released 120 falcons in southern New Mexico under section 10(j) of the Endangered Species Act.  Section 10(j) allows the USFWS to release a non-essential, experimental population into the species’ historical range without restricting current or future land management activities. 

After TPF finished hacking the releases in 2006 on the Armendaris Ranch, Tom Waddell, the Ranch Manager employed by Turner Enterprises Inc., continued to provide quail to the released individuals throughout the fall and winter and into the spring.  By late December only two falcons were showing up to feed every day.  In early spring 2007, these falcons nested successfully in an abandoned raven’s nest, fledging two chicks.  This was the first record of falcons released the previous summer (less than 9 months old), nesting successfully. 

Following this success, the TESF established an Aplomado Falcon Restoration Project on the Armendaris Ranch to assist the recovery effort’s goal of down-listing the species from endangered to threatened.