Arizona Wildlife Conservation Strategy

Semidesert Grasslands

Semidesert grasslands are most extensive across southeastern Arizona, although they also occur in the northwestern part of the state. The semidesert grasslands habitat type can be described as perennial grass-scrub dominated, primarily located between desertscrub at lower elevations and evergreen woodland, chaparral, or plains grassland at higher elevations (Brown 1994, USFS 2021). Brown (1994) described semidesert grasslands in southeastern Arizona as essentially Chihuahuan semidesert grassland. Semidesert grasslands are most abundant across southeastern Arizona, although they also occur in the northwestern part of the state. In Arizona, this habitat type can be expected as low as 3,600 feet where it abuts Chihuahuan desertscrub or Sonoran Desertscrub and as high as 4,900 to 5,500 feet where it contacts Madrean Evergreen Woodland. Annual precipitation approaches 10 inches, with most rain falling during June through August. Winters are mild and summers are hot, with low relative humidity, except during the summer monsoon season (Brown 1994).

Typical warm season perennial grasses include black grama, slender grama, chino grama, spruce top grama, bush muhly, several three-awn species, Arizona cottontop, curly mesquite, slim tridens, pappus grass, tanglehead grass, vine mesquite grass, and others (Brown 1994).

Less than 10% of semidesert grasslands remain predominantly native with low shrub cover. Across the extent of Arizona’s semidesert grasslands, significant departure from past native grassland conditions has occurred to the extent that the combination of non-native grasslands and former grasslands are no longer considered restorable. The most common non-native grasses are Lehmann lovegrass and Boer lovegrass, both African species introduced into southeastern Arizona for erosion control (Uchytil 1992, Gucker 2009). According to Brown (1994), extensive areas of this habitat type have been replaced through competition with shrubs, trees, and cacti. To such an extent that “there now are extensive landscapes where shrubs, half-shrubs, cacti, and forbs greatly outnumber, and even completely replace the grasses.” On a positive note, more than a third of the semidesert grasslands have restoration potential (Brown 1994; Gori and Enquist 2003).

Significant Habitat Features

The following describes habitat features or microhabitats in this habitat type that are of particular importance to certain species:

  • Playas, wetlands, ciénegas, and springs provide aquatic habitats that are critically important breeding areas for a variety of desert anurans, including Great Plains narrow-mouthed toad and Chiricahua and lowland leopard frogs. These habitats also provide important breeding and stopover habitats for bird species. 

  • Prairie dog colonies provide habitat diversity and other services to many grassland species. Black-tailed prairie dogs are considered keystone species, as their colonies can provide vegetation for grazers, burrows for other species, improve soil nutrients, and provide food for various predators (Hale et al. 2013).

  • Sacaton flats are areas of dense grasslands often occurring in floodplains. These habitats provide important ecosystem functions, including absorbing flood flows, controlling soil erosion, and retaining sediments while also providing quality forage and wildlife habitat. Examples of SGCN that occur here are Botteri’s sparrow and hispid cotton rat.  Today, these habitats occupy about 5% of their original distribution in southern Arizona, a result from habitat loss and encroachment of woody vegetation such as juniper (Tiller et al. 2012).  

  • Agave and yucca are found throughout this habitat type and provide an important food source for lesser long-nosed and Mexican long-tongued bats, two pollinator bat species that are important to these ecosystems.

Strategy Species

The following list represents SGCN in this habitat type that AZGFD actively manages or are watching closely due to some level of concern:

Amphibians

Chiricahua Leopard Frog, Sinaloan Narrow-mouthed Toad, Lowland Burrowing Treefrog, Lowland Leopard Frog, Plains Leopard Frog

Birds

American Kestrel, Northern Aplomado Falcon, Cassin's Sparrow, Chihuahuan Meadowlark, Cactus Ferruginous Pygmy-Owl, Golden Eagle, Western Grasshopper Sparrow, Loggerhead Shrike, Northern Masked Bobwhite, Prairie Falcon, Pyrrhuloxia, Scaled Quail, Swainson's Hawk, Western Burrowing Owl, Western Meadowlark

Invertebrates

Page Springsnail

Mammals

Antelope Jackrabbit, Black-tailed Prairie Dog, Cave Myotis, Greater Western Mastiff Bat, Lesser Long-nosed Bat, Mexican Free-tailed Bat, Mexican Long-tongued Bat

Reptiles

Massasauga, Milksnake, Mexican Gartersnake, Ornate Box Turtle, Sonora Mud Turtle

Sensitive Plant Species

The following list represents plant species that are known to occur in this habitat type:

Tonto Basin agave, Santa Cruz striped agave, Phillips agave, Trelease agave, Arizona agave, Page Springs agave, saiya, Kearney blue-star, coppermine milk-vetch, freckled milk-vetch, Santa Cruz beehive cactus, Cochise pincushion cactus, Pima pineapple cactus, Nichol Turk's head cactus, lemmon fleabane, Fish Creek fleabane, scepterbearing fleabane, San Pedro River wild buckwheat, Bartram stonecrop, Pinaleno Mountain rubberweed, Huachuca water-umbel, Lemmon's lupine, seashore cactus, beardless cinchweed, Chihuahua scurfpea, Verde breadroot, Catalina beardtongue, Maguire's penstemon, Ajo rock daisy, lace-leaf rockdaisy, Sonoita phacelia, Arizona cliff rose, Mexican skullcap, Canelo Hills ladies'-tresses, Verde four-nerve daisy, Goodding onion, White Mountains paintbrush

Additional Influential Species

The following are other wildlife species, native and non-native, that can have particular influence in this habitat type. Influential species can affect SGCN and their habitats directly and indirectly, for example altering predator/prey interactions, overgrazing, outcompeting natives, creating microhabitats, and others.

Birds

Gambel's Quail, Greater Roadrunner, Say's Phoebe

Invertebrates

Monarch

Mammals

American Pronghorn, American Badger, Banner-tailed Kangaroo Rat, Black-tailed Jackrabbit, Coyote, Mule Deer, Ord's Kangaroo Rat, Pallid Bat, Southern Grasshopper Mouse

Plants

Huachuca Water-umbel, Parry's agave, Pima Pineapple Cactus, Rusby’s milkwort, Schott Agave, Small-flowered Agave, Tusayan Flameflower

Reptiles

Desert Kingsnake, Mexican Hog-nosed Snake, Mohave Rattlesnake, Slevin's Bunchgrass Lizard, Texas Horned Lizard

Threats

The following describes the primary threats facing this habitat type, adapted from Salafsky et al. (2008). First-level threats (i.e. Agriculture, Climate Change) represent broad categories while second-level threats reflect more specific stressors to the system. For detailed information on threats to this habitat type and conservation actions being taken, see Chapter 8: Threats and Conservation Actions.

1. Agriculture

1.1: Annual and perennial nontimber crops
1.3: Livestock farming and ranching
Many agricultural practices adversely impact natural semidesert grasslands systems through loss of plant cover, biotic diversity, erosion, and dewatering. Vegetation is degraded directly through livestock grazing and clearing for farming, and indirectly through modified water levels as a result of diversions and groundwater pumping. Historically, excessive stocking rates in combination with fire suppression have led to decreased plant diversity and cover for wildlife.

3. Climate Change and Severe Weather

3.1: Habitat shifting and alteration
3.2: Droughts
3.3: Temperature extremes
A warming climate favors shrub species over perennial grasses and also results in altered precipitation patterns which change hydrological regimes and affect species distribution. Warmer ambient temperatures may surpass species temperature tolerances, causing local extirpations, or changes in distributions. Phenological changes can result in misalignment in the timing of food resource availability and the arrival of migratory birds.

4. Residential and Commercial Development

4.1: Housing and urban areas
As Arizona’s population continues to expand, demand for housing and employment centers pose threats to habitat through direct loss of habitat, and indirect impacts such as habitat fragmentation, loss of wildlife resources, light and noise pollution, and disturbance to wildlife from human and pet recreation outside the built environment.

6. Energy Production and Mining

6.3: Renewable energy
As the need for renewable energy sources increases, grassland habitats are the likely location for wind farm development. The impacts include direct mortality, loss of habitat from infrastructure development, and introduction of non-native species.

7. Human Intrusions and Disturbance

7.3: Work and other activities
Infrastructure development and human activities associated with the international border with Mexico, such as construction of roadways and lighting and increased human presence, can adversely affect wildlife through altering behavior and habitat fragmentation.

8. Invasive and Other Problematic Species

8.1: Invasive non-native species
8.2: Problematic native species
Native semidesert grasses are highly susceptible to displacement by problematic species including Lehmann’s lovegrass and buffelgrass. Meanwhile, fire suppression is allowing for the establishment of problematic native woody plants, including mesquite and juniper. Encroachment from these species can greatly alter the composition of wildlife communities that depend on this habitat type.

9. Natural System Modifications

9.1: Fire and fire suppression
Post-fire periods allow invasive vegetation, such as buffelgrass, to become established and outcompete native grasses. Meanwhile, fire suppression can allow for the establishment of woody plants, such as mesquite, that can greatly alter the grassland community.

10. Pollution

10.1: Household sewage and urban waste water
10.3: Agricultural and forestry effluents
10.4: Garbage and solid waste
Pollution can lead to habitat degradation, behavior modification from noise, direct mortality/reduced fecundity, and loss of food and water. Sources of pollution include leaking septic and fuel tanks, untreated sewage, oil or sediment on roads, lawn and agricultural fertilizers and herbicides, illegal dump sites, mine tailings, road-side litter, construction-site debris, and solid garbage and waste.

11. Transportation and Service Corridors

11.1: Roads and railroads
11.2: Utility and service lines
The creation of new roads and current travel corridors can be both a direct and indirect threat to species in the area. Vehicle traffic can create noise and visual disturbance, altering behavior of wildlife species. Road construction and maintenance may result in the direct loss of habitat and disrupt migration corridors. The construction of new roads is also in coordination with new utility and service lines on the landscape.

Conservation Actions

The following describes specific conservation actions that can be taken to reduce or eliminate threats to this habitat type, adapted from Salafsky et al. (2008). Level 1 conservation actions (i.e. Land and Water Protection) represent broad categories of potential actions, while the Level 2 conservation actions (i.e. Resource and habitat protection) are more specific.

1. Land and Water Protection

1.1: Site/area protection
  • Acquire land and water rights and pursue conservation agreements and easements in and around COAs and other priority areas. (Threats 1.1, 1.3, 3.1, 3.3, 9.1)

2. Land and Water Management

2.1: Site/area management
2.2: Invasive/problematic species control
2.3: Habitat and natural process restoration
  • Remove non-native, undesirable, and/or invasive wildlife and plant species. Monitor the success of removal efforts. (Threats 5, 8.1)
  • Improve, restore, or maintain high quality aquatic habitat to support SCGN aquatic species. Develop and maintain refuge habitats. (Threats 1.3, 3.2, 9.2)
  • Improve the quality of altered ecosystems by restoring and maintaining native plant species. This can be done by utilizing fire, improving diversity, eradication of invasive species, coordinating with partners to protect and maintain native grassland characteristics and wildlife habitat requirements, research, and maintenance once work is performed. (Threats 1.3, 3.1, 8.1, 9.2)

3. Species Management

3.1: Management of specific species of concern
3.2: Species recovery
3.4: Ex situ conservation
  • Develop and implement projects for repatriation of wildlife species populations that are currently unsustainable or extirpated, or to improve genetic resilience throughout their historical range (including refuge populations). For the listed species with recovery plans, reintroductions will be done as specified in recovery plans. (Threats 3.1, 5, 8.1, 9.1)
  • Rescue (salvage) native aquatic wildlife at risk from imminent threats, and return salvaged wildlife when conditions are appropriate. (Threats 3.1, 9.1)
: Semidesert Grasslands
  • Make presentations at scientific conferences, training workshops, and other professional meetings, field trips, wildlife fairs, media events, educational presentations, workshops, and public events, to increase awareness of effects of threats to aquatic and riparian wildlife species and habitats with an emphasis on how the threats can be reduced. (Threats 1.3, 3.1, 3.3, 5, 7.1, 8.1, 9.1)
  • Expand wildlife viewing programs to improve associated infrastructure (signs, platforms, etc.) and to reach larger and more diverse audiences. (Threats 4.3, 7.1)

5. Law and Policy

5.1: Legislation
5.2: Policies and regulations
5.4: Compliance and enforcement
  • Provide input into formal government sector legislation or policies, influencing, or providing input into policies and regulations affecting the implementation of laws at all levels, monitoring and enforcing compliance with laws, policies and regulations, and standards and codes at all levels. (Threats 1.3, 7.1, 8.1, 9.1)
  • Partner with NGOs and OHV user groups to track OHV use and damage of cross-country travel; improve coordination with partners through multi-agency regional to discuss priorities; conduct statewide law enforcement patrols targeting illegal OHV use as well as targeted saturation patrols in areas identified as critical habitat that are being adversely impacted by recreational activities. (Threats 4.3, 7.1)

6. Livelihood, Economic and Other Incentives

6.2: Substitution with environmentally-friendly goods and services
  • Engage landowners and partners to participate in Safe Harbor Agreements, Habitat Conservation Plans, Candidate Conservation Agreements (CCA), and Candidate Conservation Agreements with Assurances (CCAA). (Threats 1.3, 3.1, 9.1)

7. External Capacity Building

7.2: Alliance and partnership development
  • Collaborate with partners across different geographies (e.g., statewide, regional, national and international) to develop and implement management plans, conservation agreements, recovery actions, research, management recommendations, and to determine the effectiveness of specific management efforts. (Threats 1.3, 3.1, 7.1, 9.1)

Conservation in the Context of Climate Change

The following describes some of the conservation strategies that may mitigate the effects of a changing climate for this habitat type. Strategies have been adapted from guidelines by the Association of Fish and Wildlife Agencies (AFWA 2009).

  • Encourage and facilitate strategic planning for the renewable energy industry.

  • Identify and improve the connectivity of natural landscapes to better link wildlife populations and allow for range shifts.

  • Conduct research targeting species and habitat types likely to be vulnerable to climate change impacts.

  • Conserve a variety of habitats that support healthy populations of wildlife as the climate changes.

  • Implement long-term monitoring protocols for vulnerable species and habitats to inform adaptive management.

Other Conservation Actions

The following describe other routine or on-going conservation actions AZGFD regularly performs in this habitat type:

  • Conduct surveys and monitor populations of SGCN as specified in work plans and job statements.
  • Survey the influential species (when there is survey and management direction and protocols) within the semidesert grassland to minimize negative impacts to habitat and associated species.
  • Fund or work with partners to conduct conservation-related species research.
  • Manage recreational activities and OHV use of grassland habitat to minimize negative impacts to habitat and associated species.
  • Collect specimens or samples for taxonomic analysis, genetics, research, and/or disease testing.

Conservation Opportunity Areas (COAs)

The following represents identified COAs where conservation efforts would benefit wildlife and their habitats.

Potential Partnerships

The following is a list of the organizations and agencies that AZGFD regularly partners with on conservation efforts in this habitat type:

Important Conservation Resources

The following are relevant conservation agreements, plans, and other documents or particular interest regarding wildlife in this habitat type: