|The Jaguar is believed extinct in the United States, however there have been
sightings of Jaguars in the Arizona area.
Jaguars (Panthera onca) are typically associated with the rain forests of Central and
South America, but the species historically ranged into the arid southwestern United
States. At risk throughout their range because of habitat loss and overhunting,
jaguars currently occupy only 46% of their former (pre-1900) range.
A general shortage of information on the species in the American Southwest has led
to the widely accepted assumption that jaguars observed in Arizona and New Mexico
were not residents of the United States, but rather young, dispersing transients on
sporadic forays from Mexico.
The common assumption has been that the northernmost breeding population is
concentrated at the junction of the Aros, Bavispe, and Yaqui rivers of the United
States–Mexico border, and dispersing offspring occasionally stray north of the border.
However, the confirmed historical records of jaguars from Arizona and New Mexico
suggest a declining population of resident jaguars until the mid-1900s, with
reproduction occurring until 1910 and females documented as late as 1963. All known
jaguars in Arizona were females raising young, clearly representing a breeding
population north of the border.
Thinly distributed, population of jaguars likely inhabits the large area from southern
Arizona and New Mexico, south through the mountains of eastern Sonora, Mexico.
The interdependence of the American and Mexican portions of the population of
jaguars in the borderlands region has important implications for conservation. In
Sonora, Mexico, jaguars are seriously threatened by loss of habitat, reduced prey
populations, and hunting. In contrast, jaguars in the United States occupy large
expanses of public lands where federal protection for jaguars is enforced (United
States Fish and Wildlife Service 1997), native prey are managed at healthy
numbers, and a program to compensate producers for losses of livestock to jaguar
depredation has alleviated concerns of local stakeholders.
The overall area of potential habitat for jaguars in Arizona and New Mexico is equal
to or greater than the area of suitable habitat for jaguars in Sonora, Mexico. Thus,
the availability of suitable habitat for jaguars in the southwestern United States will
be increasingly important for the long-term survival of the species in the borderlands
region. Furthermore, with no known breeding north of the border since 1910, jaguars
in the United States also are dependent on reproduction in Mexico, with the hopes
that they will cross into the United States.
The most critical and imminent threat to jaguars in the United States is the
proposed border fence. The border fence will separate the small segment of the
borderlands population in Arizona from those in northeastern Sonora,
Mexico, thereby eliminating dispersal and preventing recovery in jaguar numbers or
range north of the border. In August 2007, the Department of Homeland Security
initiated construction of the border fence within the study area. Among the 1st
areas to be fenced were 11 km across the southern boundary of Buenos Aires
National Wildlife Refuge in the Altar Valley and a 4-km extension of the existing
fences in Nogales, Arizona, west to the Atascosa Mountain complex.
The United States Fish and Wildlife Service Biological Opinion on the border fence
detailed the combined direct and indirect impacts to jaguars, emphasizing large-scale
risks associated with fragmentation of an already small population related to loss of
gene flow. The biological opinion also warned that migrant traffic and associated law
enforcement activities will likely shift from the desert floor into mountainous habitats
where disturbance by humans and habitat degradation will have greater negative
effects on jaguars than before.
This is important for jaguars because the mountainous Baboquivari and Atascosa
Mountain complexes appear critically important for maintaining connectivity between
the Arizona and Sonora, Mexico, portions of the jaguar population in the borderlands.
An extensive fence along the United States–Mexico border would likely effectively
fence jaguars out of the United States, preventing dispersal and gene flow from
northern Mexico, and bring an end to naturally occurring jaguars in the United States.
The Future For Jaguars
Direct killing of jaguars in predator control efforts is another very serious threat,
especially in Mexico. Also in the United States, recent debates over designation of
Critical Habitat and federal restrictions on local land-use practices have alienated
important local conservation stakeholders, causing greater animosity toward jaguars
that further threatens the safety of jaguars.
On a broader scale, Arizona has the fastest-growing human population in the United
States and housing developments are severing connective habitats. Finally, large-
scale, open-pit mines threaten known core habitat of jaguars in the Atascosa
Mountain complex and potential habitat in the Patagonia/Santa Rita Mountain complex.
The current population of jaguars in the borderlands region, and particularly the
United States portion of that population, appears to be dependent on large expanses
of core and connective habitats for dispersal and cross-border movements within the
bioregion of southern Arizona and New Mexico and eastern Sonora, Mexico.
If this cohesive habitat and gene flow throughout the region are disrupted by the
proposed fence along the border, it is our belief that the population of jaguars in the
borderlands will be at great risk and that jaguars will not persist in the United
Corwin, J. 100 Heartbeats: The Race to Save Earth's Most Endangered Species.
Mahler, R. The Jaguar's Shadow: Searching for a Mythic Cat. 2009.
Sartore, J. Rare: Portraits of America's Endangered Species. 2010.