Reports and Journal Articles

An ecologically based classification system, when accompanied by digitized maps of biotic communities, has been shown to be useful for plotting and assessing affinities of plants and animals in the southwestern United States and northwestern Mexico… See more

Mexico is the fourth richest area in the world in terms of biodiversity (Challenger 1998; Flores & Gerez 1988; Mittermeier & Goettsch Mittermeier 1992). Efforts to set up nature reserves in Mexico have had three major periods: the beginning… See more

Trip report on 2005 biological inventory of the Rio Aros and Yaqui from Natora, Sonora to Sahuaripa. Rafts and inflatable kayaks were used to gain access to this remote and rugged area. Trip participants included Aaron Flesch, Lane Larsen, Samia… See more

The Sonoyta mud turtle, Kinosternon sonoriense longifemorale, is endemic to a small area in south- western Arizona and northwestern Sonora. The only U.S. population, at Quitobaquito, declined from several hundred in the 1950s to fewer than 100 in… See more

About 1,500 collections from within 100 kilometers of the Arizona border in Sonora yielded noteworthy records for 164 plants including 44 new species (12 non-native) for Sonora and 12 (six non-native) for Mexico, conservation species, and regional… See more

Why This Report? In 2004, two major industrial developments—a liquid natural gas (LNG) regasification facility by Houston-based DKRW Energy and a “clean fuels” refinery by Arizona Clean Fuels of Phoenix, Arizona-- were announced by their promoters… See more

The western and southern edges of the Madrean Sky Island region are poorly defined and have received little study. After exploring mountains in these areas, we documented range extensions and additional records for several species of interest.… See more

The status of beaver (Castor canadensis) in northeastern Sonora, Mexico, is uncertain. We surveyed the Cajon Bonito River to assess the beaver’s status and habitat and found five colonies. Limiting factors appear to be pollution due to animal waste… See more

The Peloncillo Mountains and its surrounding valleys, ranges and drainages anchor the center of the Sky Island region—a region of the southwestern United States and northwestern Mexico characterized by isolated mountain ranges separated by desert… See more

Presently, the flora of the Sierra de Mazatán contains 357 species of vascular plants distributed in 248 genera and 80 families. The families with the most species are Asteraceae (48), Fabaceae (45), Poaceae (28), Euphorbiaceae (18), and… See more

Executive Summary A bi-national team worked from August 2001 through February 2003 to systematically analyze the best scientific information available for the 30-million acre (12-million ha) Apache Highlands ecoregion. The objective was to identify… See more

From July 1998 to July 2000 we collected locality information and habitat associations for 36 records of the Endangered ocelot Leopardus pardalis in the Mexican State of Sonora. Twenty-seven (75%) of the records for which we could determine the… See more

Grasslands of central and southern Arizona, southwestern New Mexico and northern Mexico, an area known as the Apache Highlands Ecoregion, have undergone dramatic vegetation changes over the last 130 years, including encroachment by shrubs, loss of… See more

While biologists have been aware of the existence of native Mexican trouts for over a century, they have received little study. The few early studies that did muchmore than mention their existence began in the 1930s and continued into the early… See more

An Endangered Species within Organ Pipe Cactus National Monument: Historical Significance and Management Challenges The largest body of water at Organ Pipe Cactus National Monument is Quitobaquito springs and pond, home to the Quitobaquito desert… See more

The Sonoran Desert is considered to be the most “tropical” of the North American deserts. Its climate is virtually frost-free, and summer rainfall comes from the tropical oceans. The Sonoran Desert’s structurally diverse vegetation, which includes… See more

More than one third of Forrest Shreve's (1951 ) Sonoran Desert lies within the boundaries of Sonora, the second largest state in Mexico. Five of the seven major vegetational subdivisions of the Sonoran Desert are found within Sonora as well, more… See more

Trip report from 1998 expedition to the Sierra de los Ajos by a group of diverse biologists and geologists.

The pine-oak forests of the Sierra Madre Occidental, a mountain range in NW Mexico, have recently been recognized as an area of high endemism and biodiversity. Selective logging threatens three bird species endemic to this habitat, who depend on… See more

Biodiversity and Management of the Madrean Archipelago. The Sky Islands of Southwestern United States and Northwestern Mexico. Previous work on biogeographic isolation has concerned itself with oceanic island chains, islands associated with… See more

The old growth forest on Mt. Graham (Pinaleno Mountains) of eastern Arizona is comprised of forest patches rather than being homogeneous in composition. These patches reflect the heterogeneity of disturbances that occur on the mountain. The two… See more

Interest in the new philosophy of ecosystem management led the Forest Service to sponsor a study of past land use in the Lone Mountain/San Rafael Valley Ecosystem Project Area, part of the Sierra Vista Ranger District of Coronado National Forest in… See more