Treesearch

The Sky Island region of southwestern United States and northwestern Mexico consists of isolated mountain ranges separated by deserts and grasslands. It mixes elements from five major ecosystems: the Rocky Mountains, Sierra Madre Occidental, the Sonoran and Chihuahuan deserts and the Neotropics. Here some Neotropical species reach their northern ranges, such as jaguars (Panthera onca) and ocelots (Leopardus pardalis). Sky Island Alliance seeks to build cooperative relationships with landowners in Sonora and public land managers in Arizona to facilitate scientific research, encourage large...

We investigated the monthly activity rates of bobcats (Lynx rufus), gray foxes (Urocyon cinereoargenteus) and four of their potential prey species, antelope jackrabbits (Lepus alleni), black-tailed jackrabbits (Lepus californicus), desert cottontails (Sylvilagus audubonii) and eastern cottontails (Sylvilagus floridanus), in Saguaro National Park using remote camera trap data. We analyzed images taken over an 11-month period and over 10,000 camera nights and compared the time of day, month, and location of photographs of bobcats, gray foxes and four lagomorph species. Our findings suggest...

The Horseshoe 2 Fire burned 90,226 ha (222,954 ac) of the Chiricahua Mountains in the Coronado National Forest of southeast Arizona from May 8 to June 25, 2011. This mountain range in the Madrean Archipelago was burned by widespread fires prior to 1890, numerous small fires after 1890, and, more recently, the 11,129 ha (27,500 ac) Rattlesnake Fire in 1994. The latter fire resulted in significant erosion during post-fire monsoon storms that eroded deep gullies (~10 m) in Ward Canyon (upper West Turkey Creek). Post-fire runoff deposited large amounts of sediment in lower channels, particularl...

In this project we mapped the different types of border barriers, identified impacts of border infrastructure on public and private lands and conducted spatial analyses within the approximately 200 miles of international border in the Sky Island region. The Sky Island region, bisected by the U.S.-Mexico border, is critically important for its biodiversity and continental connectivity. Only on the Arizona side is the border lined with protected areas such as San Bernardino and Buenos Aires National Wildlife Refuges, San Pedro Riparian National Conservation Area, Coronado National Memorial,...

Post-fire watershed recovery is influenced by numerous variables but one of the most important factors is the rate of re-establishment of vegetative cover. Burned Area Emergency Response (BAER) teams, along with other agencies (Natural Resource Conservation Service, state, counties, cities, etc.), prescribe temporary post-fire mitigation treatments based on expected post-fire responses of watersheds to fire-caused damage and based on threats to life, property, and resources associated with watershed damage. The objective of this project was to develop tools to more accurately assess the...

The Gila River Basin Native Fishes Conservation Program was established to conserve native fishes and manage against nonnative fishes in response to several Endangered Species Act biological opinions between the Bureau of Reclamation and the U.S. Fish and Wildlife Service on Central Arizona Project (CAP) water transfers to the Gila River basin. Populations of some Gila River native fish species are rare in the wild and appear on the verge of extirpation. The CAP Program provides monies to undertake and support conservation actions for five priority fishes and other native fishes in the...

There is a significant history of cooperative efforts between Mexico and the United States on natural resource management issues. Mexico and the United States have jointly conducted research and developed range management technologies. Bringing these technologies together and improving technical communications are an ongoing process. This paper discusses a potential tool that can provide a common denominator for both countries to more easily frame, describe, and share data relative to rangeland resources. The objective is to present possibilities for utilizing current data and provide a...

LiDAR (Light detection and ranging) is a tool with potential for characterizing wildlife habitat by providing detailed, three-dimensional landscape information not available from other remote sensing applications. The ability to accurately map structural components such as canopy height, canopy cover, woody debris, tree density, and ground surface has potential to improve wildlife habitat models because animals interact and respond to three-dimensional habitat features. Prior to LiDAR, accurate measurements of structural features were difficult to obtain over large areas as other remote...

Grasslands of the Sky Islands region once covered over 13 million acres in southeastern Arizona and adjacent portions of New Mexico, Sonora, and Chihuahua. Attempts to evaluate current ecological conditions suggest that approximately two thirds of these remain as intact or restorable grassland habitat. These grasslands provide watershed services such as flood control and aquifer recharge across the region, and continue to support dozens of species of concern. Prioritizing conservation interventions for these remaining grassland blocks has been challenging. Reliable data on condition and...

Riparian grasslands dominated by Sporobolus wrightii (big sacaton) were once widely distributed in the intermountain basins of the Madrean Archipelago. These alluvial grasslands are still recognized as key resources for watershed function, livestock, and wildlife. The upper Cienega Creek watershed in SE Arizona is thought to harbor some of the region’s most extensive sacaton stands. Documenting their extent and ecological state is important for informing management in this valley and for contributing to a clearer picture of this community’s status across the region. Our objectives were to...