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Research about Arizona, California, New Mexico, Texas

Source-linked reports with geographic coverage including Arizona, California, New Mexico, Texas.

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Wildfire risk and hazardous fuel reduction treatments along the US-Mexico border: A review of the science (1985-2019)

The ecosystems along the border between the United States and Mexico are at increasing risk to wildfire due to interactions among climate, land-use, and fuel loads. A wide range of fuel treatments have been implemented to mitigate wildfire and its threats to valued resources, yet we have little information about treatment effectiveness. To fill critical knowledge gaps, we reviewed wildfire risk and fuel treatment studies that were conducted near the US-Mexico border and published in the peer-reviewed literature between 1986 and 2019. The number of studies has grown during this time in warm desert to forest ecosystems on primarily federal lands. The most common study topics included fire effects on native species, the role of invasive species and woody encroachment on wildfire risk, historical fire regimes, and remote sensing and modeling to study wildfire risk across the landscape. A majority of fuel treatment studies focused on prescribed burns, and fuel treatments collectively had mixed effects on mitigating future wildfire risk and threats to ecosystems depending on vegetation and fire characteristics. The diversity of ecosystems and land ownership along the US-Mexico border present unique challenges for understanding and managing wildfire risk, and also create opportunities for collaboration and cross-site studies to promote knowledge across broad environmental gradients.

Arizona, California, New Mexico, Texas

Jaguar surveying and monitoring in the United States

Because of the jaguar’s ( Panthera onca ) endangered status under the Endangered Species Act (ESA) of 1973 throughout its range (from Arizona in the north to Argentina in the south), jaguar individuals and populations are monitored to varying degrees throughout their range. Knowledge gained from monitoring jaguars is helpful for wildlife managers who are responsible for conserving this species. The University of Arizona (UA) has conducted a multiyear surveying and monitoring effort for jaguars and ocelots in southern Arizona and New Mexico. The purpose of this work was to establish an effective surveying and monitoring system for jaguars along the United States-Mexico border. Surveying and monitoring in this study focused on the United States side of the border, but the methods could also be used in Mexico. The intent was to develop and implement a surveying and monitoring system that would provide the greatest probability of recording jaguar presence in, and passage through, the border area. This project established and implemented a noninvasive system for detecting and monitoring jaguars. The study area incorporates most of the mountainous areas north of the United States-Mexico international border and south of Interstate 10, from the Baboquivari Mountains in Arizona to the Animas Mountains in New Mexico. We used two primary methods to detect exact jaguar locations: paired motion-sensor trail cameras, and genetic testing of large carnivore scat collected in the field. We emphasize that this project used entirely noninvasive methods and no jaguars were captured, radiocollared, baited, or harassed in any way. Scat sample collection occurred during the entire field part of the study, but was intensified with the use of a trained scat detection dog following the first jaguar photo detection event (photo detection event was October 2012, scat detection dog began working January 2013). We also collected weather, vegetation, and geographic information system (GIS) data to analyze in conjunction with photo and video data. The results of this study are intended to aid and inform future management and conservation practices for jaguars and ocelots in this region.

Arizona, California, New Mexico, Texas

Feather isotope analysis reveals differential patterns of habitat and resource use in populations of white-winged doves

The white-winged dove ( Zenaida asiatica ) serves an important ecological role as a diurnal pollinator of the saguaro cactus in the Sonoran desert and an economic role as a highly sought after game bird in North America. White-winged doves are intimately linked to anthropogenic changes on the landscape and because of this, have experienced dramatic population fluctuations over the last 75 years in response, both positively and negatively, to anthropogenic changes on the landscape. To understand the factors driving population growth and decline of migratory species like the white-winged dove, it is imperative we study resource use on both their breeding and wintering grounds. To understand how populations are distributed on the wintering grounds, we tested an alternative to band recovery approaches by using stable isotope analysis. Before we could use isotope analysis to link breeding and wintering locations for this species, we first needed to determine if hydrogen (δ 2 H) and carbon (δ 13 C) stable isotopes in feather tissue (δ 2 H f and δ 13 C f , respectively) could differentiate among populations of white-winged doves across their breeding range in Texas, New Mexico, and Arizona. δ 2 H f and δ 13 C f not only differentiated between populations of white-winged doves that breed in the United States, but δ 2 H f also provided further differentiation in white-winged doves that breed in native Sonoran Desert and agricultural habitats in the western portion of their range. Ecological processes associated with desert resources and anthropogenic influences, specifically saguaro cacti and irrigated crops, largely determined δ 2 H f in some white-winged doves in Arizona whereas δ 2 H of precipitation (δ 2 H p ) largely determined δ 2 H f of doves in New Mexico and Texas. This study highlights the usefulness of stable isotope analysis to differentiate populations of animals across the landscape and the insight isotopes can provide into habitat and resource use. Published 2015. This article is a U.S. Government work and is in the public domain in the USA.

Arizona, California, New Mexico, Texas