Treesearch

Gila Monsters (Heloderma suspectum) are symbolic species of the desert landscapes of the southwestern United States and Mexico. These large, venomous lizards appear to be rather uncommon throughout their range, but our understanding of their population status is complicated by the fact that they spend most of their lives underground rather than actively moving through their preferred upland habitat. Personnel and volunteers from the U.S. Fish and Wildlife Service have opportunistically monitored Gila Monsters in the vicinity of San Bernardino and Leslie Canyon National Wildlife Refuges in...

The Tucson shovel-nosed snake (Chionactis annulata klauberi) is a small specialized colubrid associated with sandy loams of the elevated portions of the Lower Colorado River Valley Sonoran Desert in central Arizona. This taxon is a recently redefined subspecies based on genetic data, and may be extirpated in the Tucson region, including the type locality. A recent (USFWS 2014) decision against protecting it was based in part on an expansive definition of its geographic range and a habitat model. Here, we redefine the subspecies distribution by uniting published results of mitochondrial and...

Beaver (Castor canadensis) were reintroduced beginning in 1999 on the San Pedro Riparian National Conservation Area. Herbivory is the most obvious effect from beaver, but little research exists of herbivory effects after reintroduction. Fire processes may also have substantial effects to vegetation, and both beaver and fire are important ecological components for comparing effects and subsequent management decisions. The objective of this research, conducted during 2008 and 2009, was to determine any effects to foliage density caused by beaver herbivory and wildfire as compared to control...

Wild felids play an important role in the dynamics of the tropical forests where they live, through the processes of depredation they exert on their prey. The populations of these carnivorous mammals have decreased throughout their range, due to conflicts with humans, habitat destruction and fragmentation. In order to know the abundance of wild cats in the Area of Protection of Flora and Fauna Sierra de Álamos-Cuchujaqui, a monitoring was carried out with the 105 trap cameras during two sampling periods (August-September and October-December of 2016) in two sites in the protected area. The...

Scenario planning is a strategy or framework that aids making decisions under uncertainty. Inspired by widespread use in the areas of military and business, recent work has applied the strategy to anticipate the effects of climate change on natural resource management. Most scenario planning efforts identify scenarios based on uncertain response in two key drivers of change (e.g., climate, ecology, land use) and then consider the resultant effects on the system and possible changes to management protocols. We present an alternative implementation of scenario planning - Scenario Planning...

Velvet mesquite (Prosopis velutina) in riparian settings is known for developing bosques, stands of mature trees with an open understory that supports other native plants and wildlife. Many historic mesquite bosques in the Madrean Archipelago have been cleared to allow farming on river floodplains. In some cases, cultivation of those farm fields was later abandoned, leading to a rapid recolonization by mesquite. The result has been dense stands of small mesquites, all competing for limited soil moisture and groundwater supply. We looked at the possibility of advancing one of those stands...

The USA National Phenology Network (USA-NPN) is a federally-funded, national-scale science and monitoring initiative focused on phenology, the study of seasonal life cycle events, as an approach to understanding how plants, animals, and landscapes respond to environmental variation and change. Through the collection and curation of professional and citizen scientist-derived datasets, a primary aim of the Network is to inform decisions across a diversity of realms, from natural resource management and conservation to public health and human well-being. The Network does this by developing...

Since 2015 the Madrean Discovery Expeditions (MDE) of GreaterGood.org (GGO) has completed biotic inventories in the Sierras Buenos Aires, Cucurpe, Elenita, Juriquipa, and el Tigre in northeastern Sonora, Mexico. The MDE Education program shares the results of the Expeditions with residents who live in the adjacent river valleys. Raising awareness about the amazing diversity of animals and plants will help protect these unique Sky Island mountain ranges for the future. MDE educators have given presentations to about 1751 students and 101 teachers in 25 schools in 22 towns in northeastern...

Although increasingly separated by physical and political barriers, the lands on either side of the US-Mexico are united by shared ecosystems, watersheds, and conservation issues. Both sides of the border contain numerous protected natural areas, including parks, forests, and wildlife refuges, and some of the national parks in the two countries are designated "sister parks" in a formal program that encourages collaboration and mutual support. This paper, based on a workshop held at the Madrean Conference, explores the many challenges and opportunities in creating on the ground conservation...

The jurisdiction of the Clean Water Act over aquatic and riparian habitats in the Western US is continuing to shrink in response to past Supreme Court decisions, leaving a gap in water quality governance for an increasing number of streams in the Western US. Arizona is preparing to remove certain streams, springs, wetlands, and lakes from the state’s water quality standards based on these decisions. Arizona also seeks primacy for future determinations of Clean Water Act jurisdiction under Section 404 for non-navigable waters. Transfer of those Clean Water Act responsibilities to the state...