Mammal Species of the World
- Original description: Baird, Spencer., 1858. Proceedings of the Academy of Natural Sciences of Philadelphia, 10:116.
The California leaf-nosed bat, the most northern member of the Phyllostomidae, lives in Northen Mexico, Baja California, southern Arizona, southern California and southern Nevada (Constantine 1998).
Biogeographic Regions: nearctic (Native )
occurs (regularly, as a native taxon) in multiple nations
Regularity: Regularly occurring
Type of Residency: Year-round
Global Range: Baja California, Sonora, and northern Sinaloa, Mexico, north to southern California, southern and western Arizona, and southern Nevada (Jones and Carter 1976). Hall (1981) included Tamaulipas and San Luis Potosi in the range of CALIFORNICUS. Northern Sinaloa and southwestern Chihuahua to southern Nevada, southern California; Baja California and Tamaulipas (Koopman, in Wilson and Reeder 1993).
The Macrotus californicus has short broad wings and huge ears and eyes (Tuttle 1998). It's skull has no post orbital processes and a complete premaxillae.
Average mass: 8-17 g.
Average wingspan: 33-35 cm.
Average mass: 11.7 g.
Average basal metabolic rate: 0.082 W.
Length: 8 cm
Size in North America
Average: 94.3 mm
Range: 85-99 mm
Range: 12-22 g
Differs from Leptonycteris and Choeronycteris in Arizona in having a shorter rostrum, no bristlelike papillae on the tongue, first upper incisor in contact with the canine and usually also in contact with the second premolar, ears joined together near the base, and a larger number of chromosomes (2N=40 vs. 2N=32 or 16) (Hoffmeister 1986). Differs from M. WATERHOUSII by having chromosomes 2N=40 rather than 2N=46, interorbital width of 3.8 mm or less, smaller canines, larger ears, and larger auditory bullae (Davis and Baker 1974, Anderson and Nelson 1965; see also Hoffmeister 1986).
Sonoran Desert Habitat
This taxon is found in the Sonoran Desert, which comprises much of the state of Sonora, Mexico, most of the southern half of the USA states of Arizona, southeastern California, most of the Baja California peninsula, and the numerous islands of the Gulf of California. Its southern third straddles 30° north latitude and is a horse latitude desert; the rest is rainshadow desert. It is lush in comparison to most other deserts. There is a moderate diversity of faunal organisms present, with 550 distinct vertebrate species having been recorded here.
The visually dominant elements of the landscape are two lifeforms that distinguish the Sonoran Desert from the other North American deserts: legume trees and large columnar cacti. This desert also supports many other organisms, encompassing a rich spectrum of some 2000 species of plants, 550 species of vertebrates, and untolled thousands of invertebrate species.
The Sonoran Desert prominently differs from the other three deserts of North America in having mild winters. Most of the area rarely experiences frost, and the biota are partly tropical in origin. Many of the perennial plants and animals are derived from ancestors in the tropical thorn-scrub to the south, their life cycles attuned to the brief summer rainy season. The winter rains, when ample, support great populations of annuals (which make up nearly half of the plant species). Some of the plants and animals are opportunistic, growing or reproducing after significant rainfall in any season.
Creosote Bush (Larrea divaricata) and White Bursage (Ambrosia dumosa) vegetation characterize the lower Colorado River Valley section of the Sonoran. The Arizona upland section to the north and east is more mesic, resulting in greater species diversity and richness. Lower elevation areas are dominated by dense communities of Creosote Bush and White Bursage, but on slopes and higher portions of bajadas, subtrees such as palo verde (Cercidium floridum, C. microphyllum) and Ironwood (Olneya tesota), saguaros (Carnegiea gigantia), and other tall cacti are abundant. Cresosote Bush (Larrea tridentata) and White Bursage (Ambrosia dumosa) form the scrub that dominates the northwest part of the Sonoran Desert. This association thrives on deep, sandy soils in the flatlands. Where the dunes allow for slight inclination of the slope, species of Mesquite (Prosopis), Cercidium, Ironwood (Olneya tesota), Candalia, Lycium, Prickly-pear (Opuntia), Fouquieria, Burrobush (Hymenoclea) and Acacia are favored. The coastal plains of Sonora are composed of an almost pure Larrea scrub. Away from the Gulf influence in the area surrounding the Pinacate, Encelia farinosa, Larrea tridentata, Olneya, Cercidium, Prosopis, Fouquieria and various cacti species dominate the desert.
Many wildlife species, such as Sonoran Pronghorn Antelope (Antilocapra sonoriensis EN), Desert Bighorn Sheep (Ovis canadensis nelsoni) and the endemic Bailey's Pocket Mouse (Chaetodipus baileyi) use ironwood, cacti species and other vegetation as both shelter from the harsh climate as well as a water supply. Other mammals include predators such as Puma (Felis concolor), Coyote (Canis latrans) and prey such as Black-tailed Jackrabbit (Lepus californicus), and the Round-tailed Ground Squirrel (Spermophilus tereticaudus). Other mammals able to withstand the extreme desert climate of this ecoregion include California Leaf-nosed Bat (Macrotus californicus) and Ring-tailed Cat (Bassariscus astutus).
Three endemic lizards to the Sonoran Desert are: the Coachella Fringe-toed Lizard (Uma inornata EN); the Flat-tail Horned Lizard (Phrynosoma mcallii NT); and the Colorado Desert Fringe-toed Lizard (Uma notata NT); an endemic whiptail is the San Esteban Island Whiptail (Cnemidophorus estebanensis). Non-endemic special status reptiles in the ecoregion include the Desert Tortoise (Gopherus agassizii VU) and the Gila Monster (Heloderma suspectum NT).
There are twenty-four anuran species occurring in the Sonoran Desert, one of which is endemic, the Sonoran Green Toad (Anaxyrus retiformis). Other anurans in the ecoregion are: California Treefrog (Pseudacris cadaverina); Canyon Treefrog (Hyla arenicolor); Lowland Burrowing Frog (Smilisca fodiens); Mexican Treefrog (Smilisca baudinii); Madrean Treefrog (Hyla eximia); Sabinal Frog (Leptodactylus melanonotus); Northwest Mexico Leopard Frog (Lithobates magnaocularis); Brown's Leopard Frog (Lithobates brownorum); Yavapai Leopard Frog (Lithobates yavapaiensis); Mexican Cascade Frog (Lithobates pustulosus); Mexican Leaf Frog (Pachymedusa dacnicolor); Red Spotted Toad (Anaxyrus punctatus); Sinaloa Toad (Incilius mazatlanensis); Sonoran Desert Toad (Incilius alvarius); Eastern Green Toad (Anaxyrus debilis); New Mexico Spadefoot (Spea multiplicata); Great Plains Toad (Anaxyrus cognatus); Couch's Spadefoot Toad (Scaphiopus couchii); Cane Toad (Rhinella marina); Elegant Narrowmouth Toad (Gastrophryne elegans); Little Mexican Toad (Anaxyrus kelloggi); Great Plains Narrowmouth Toad (Gastrophryne olivacea); and Woodhouse's Toad (Anaxyrus woodhousii).
The Sonoran Desert is recognized as an exceptional birding area. Forty-one percent (261 of 622) of all terrestrial bird species found in the USA can be seen here during some season of the year. The Sonoran Desert, together with its eastern neighbor the Chihuahuan Desert, is the richest area in in the USA for birds, particularly hummingbirds. Among the bird species found in the Sonoran Desert are the saguaro-inhabiting Costa's Hummingbird (Calypte costae), Black-tailed Gnatcatcher (Polioptila melanura), Phainopepla (Phainopepla nitens) and Gila Woodpecker (Melanerpes uropygualis). Perhaps the most well-known Sonoran bird is the Greater Roadrunner (Geococcyx californianus), distinguished by its preference for running rather than flying, as it hunts scorpions, tarantulas, rattlesnakes, lizards, and other prey. The Sonoran Desert exhibits two endemic bird species, the highest level of bird endemism in the USA. The Rufous-winged Sparrow (Aimophila carpalis) is rather common in most parts of the Sonoran, but only along the central portion of the Arizona-Mexico border, seen in desert grasses admixed with brush. Rare in extreme southern Arizona along the Mexican border, the endemic Five-striped Sparrow (Aimophila quinquestriata) is predominantly found in canyons on hillsides and slopes among tall, dense scrub.
- C. Michael Hogan, Mark Dimmitt, Arizona-Sonora Desert Museum, World Wildlife Fund. 2013."Gulf of California xeric scrub". Encyclopedia of Earth, National Council for Science and the Environment, Washington DC ed.Mark McGinley.
- Mark A.Dimmitt. Biomes & Communities of the Sonoran Desert, Arizona-Sonoran Desert Museum.
Habitat and Ecology
Mojave Desert Habitat
This taxon is found in the Mojave Desert, the smallest of the four North American deserts. While the Mojave lies between the Great Basin Shrub Steppe and the Sonoran Desert, its fauna is more closely allied with the lower Colorado division of the Sonoran Desert. Dominant plants of the Mojave include Creosote Bush (Larrea tridentata), Many-fruit Saltbush (Atriplex polycarpa), Brittlebush (Encelia farinosa), Desert Holly (Atriplex hymenelytra), White Burrobush (Hymenoclea salsola), and Joshua Tree (Yucca brevifolia), the most notable endemic species in the region.
The Mojave’s warm temperate climate defines it as a distinct ecoregion. Mojave indicator species include Spiny Menodora (Menodora spinescens), Desert Senna (Cassia armata), Mojave Indigobush (Psorothamnus arborescens), and Shockley's Goldenhead (Acamptopappus shockleyi). The Mojave supports numerous species of cacti, including several endemics, such as Silver Cholla (Opuntia echinocarpa), Mojave Prickly Pear (O. erinacea), Beavertail Cactus (O. basilaris), and Cotton-top Cactus (Echinocactus polycephalus).
While the Mojave Desert is not so biologically distinct as the other desert ecoregions, distinctive endemic communities occur throughout. For example, the Kelso Dunes in the Mojave National Preserve harbor seven species of endemic insects, including the Kelso Dunes Jerusalem Cricket (Ammopelmatus kelsoensis) and the Kelso Dunes Shieldback Katydid (Eremopedes kelsoensis). The Mojave Fringe-toed Lizard (Uma Scoparia), while not endemic to the dunes, is rare elsewhere. Flowering plants also attract butterflies such as the Mojave Sooty-wing (Pholisora libya), and the widely distributed Painted Lady (Vanessa cardui).
There are a total of eight amphibian species present in the Mojave Desert all of which are anuran species: the endemic Relict Leopard Frog (Lithobates onca); the endemic Amargosa Toad (Anaxyrus nelsoni); Lowland Leopard Frog (Lithobates yavapaiensis); Red-spotted Toad (Anaxyrus punctatus); Southwestern Toad (Anaxyrus microscaphus); Great Basin Spadefoot (Spea intermontana); Great Plains Toad (Anaxyrus cognatus); and the Pacific Treefrog (Pseudacris regilla).
The native range of California’s threatened Desert Tortoise (Gopherus agassizii) includes the Mojave and Colorado Deserts. The Desert Tortoise has adapted for arid habitats by storing up to a liter of water in its urinary bladder. The following reptilian fauna are characteristic of the Mojave region in particular: Gila Monster (Heloderma suspectum NT); Western Banded Gecko (Coleonyx variegatus), Northern Desert Iguana (Dipsosaurus dorsalis), Western Chuckwalla (Sauromalus obesus), and regal horned lizard (Phrynosoma solare). Snake species include the Desert Rosy Boa (Charina trivirgata gracia), Mojave Patchnose Snake (Salvadora hexalepis mojavensis), and Mojave Rattlesnake (Crotalus scutulatus).
Endemic mammals of the ecoregion include the Mojave Ground Squirrel (Spermophilus mohavensis) and Amargosa Vole (Microtus californicus scirpensis); and the California Leaf-nosed Bat (Macrotus californicus).
- C. Michael Hogan & World Wildlife Fund. 2013."Mojave Desert". Encyclopedia of Earth, National Council for Science and the Environment, Washington DC ed.Mark McGinley.
- Michael G. Barbour and William Dwight Billings. 2000. North American Terrestrial Vegetation. Cambridge University Press. ISBN 0-521-55986-3.
This species can be found in the caves and abandoned mines in deserts of South West North America. In the winter, they choose roosts that are geothermically heated (Tuttle 1998).
Terrestrial Biomes: desert or dune ; chaparral
Comments: Lowland desert scrub. Uses caves or abandoned mine tunnels for rest site during day. Small groups may also use natural rock shelters in canyon walls. Uses shelter of open buildings, bridges, rocks, and mines for temporary night roosts. Old mine tunnels or caves may be used as nurseries.
Non-Migrant: Yes. At least some populations of this species do not make significant seasonal migrations. Juvenile dispersal is not considered a migration.
Locally Migrant: No. No populations of this species make local extended movements (generally less than 200 km) at particular times of the year (e.g., to breeding or wintering grounds, to hibernation sites).
Locally Migrant: No. No populations of this species make annual migrations of over 200 km.
M. californicus is an insectivore. It uses its unuusal hovering ability to capture insects from the ground instead of from the air. It also uses its keen sense of vision over echolocation whenever light is adequate (Bell 1986). They feed up to 1.3km from their roost (Harris 1999).
Foods eaten include: crickets, moths, beetles, and grasshoppers, cicadas and caterpillars.
Animal Foods: insects
Primary Diet: carnivore (Insectivore )
Comments: Eats mainly large, night-flying insects (beetles, grasshoppers, moths) taken in flight and insect larvae, which may be taken from bushes or ground. Flys low, within a meter of the ground, or hovers while foraging. Individuals from southern Arizona and Sonora, Mexico, are known to include fruit in the diet. See Gardner (1977) for further details.
M. californicus plays an important role in insect control.
Known prey organisms
This list may not be complete but is based on published studies.
Usually found roosting in groups, but individuals do not cluster. Males live in small bachelor groups in July and August, join females in September. Has few predators. Maximum life expectancy estimated at more than 10 years (Anderson 1969). Forages up to 1.3 km from roost. Most activity probably closer to roost (Vaughan 1959).
Life History and Behavior
Comments: Does not hibernate. May be less active during the winter. Rests during the day. Begins to leave daytime roost to forage for food about 1 hour after sunset, returns before sunrise. Rests during the night between periods of activity.
Status: wild: 10.4 years.
Lifespan, longevity, and ageing
During the summer, most males form separate colonies close to female groups of around 100-500 members. However, a handful of dominant males stay within the female colony and have harem groups consisting of 5-25 females and young (Tuttle 1998).
Mating System: polygynous
Mating takes place in the fall. For the first several months of gestation, the embryo develops extremely slowly. Development speeds up in the spring, and young are born in June. (Tuttle 1998).
Breeding season: Mating takes place in the fall, birth in the spring
Range number of offspring: 1 to 2.
Average number of offspring: 1.
Average gestation period: 8 months.
Average weaning age: 1 months.
Average age at sexual or reproductive maturity (female): 6 months.
Average age at sexual or reproductive maturity (male): 12 months.
Key Reproductive Features: iteroparous ; seasonal breeding ; gonochoric/gonochoristic/dioecious (sexes separate); viviparous
Average gestation period: 270 days.
Average number of offspring: 1.
Average age at sexual or reproductive maturity (female)
Sex: female: 120 days.
Infants are born with open eyes and ears and a full coat of fur. Infants nurse for one month. While females become sexually mature their first fall, males take a full year to reach sexual maturity (Harris 1999).
Parental Investment: female parental care
Insemination, ovulation, and fertilization occur mainly late September-early October; embryonic development is delayed, gestation lasts about 8 months (Anderson 1969). In Arizona, females usually bear 1 young in May or June. Young are weaned in about 1 month. Females first breed in their first fall, males the following year. Females form maternity colonies.
Molecular Biology and Genetics
Statistics of barcoding coverage: Macrotus californicus
Public Records: 0
Specimens with Barcodes: 7
Species With Barcodes: 1
IUCN Red List Assessment
Red List Category
Red List Criteria
Populations of this species are definitely decreasing. Human disturbances in caves and the reestablishment of mines is driving these animals out of their homes.
Temperate North American bats are now threatened by a fungal disease called “white-nose syndrome.” This disease has devastated eastern North American bat populations at hibernation sites since 2007. The fungus, Geomyces destructans, grows best in cold, humid conditions that are typical of many bat hibernacula. The fungus grows on, and in some cases invades, the bodies of hibernating bats and seems to result in disturbance from hibernation, causing a debilitating loss of important metabolic resources and mass deaths. Mortality rates at some hibernation sites have been as high as 90%. While there are currently no reports of Macrotus californicus mortalities as a result of white-nose syndrome, the disease continues to expand its range in North America.
US Federal List: no special status
CITES: no special status
IUCN Red List of Threatened Species: least concern
- Cryan, P. 2010. "White-nose syndrome threatens the survival of hibernating bats in North America" (On-line). U.S. Geological Survey, Fort Collins Science Center. Accessed September 16, 2010 at http://www.fort.usgs.gov/WNS/.
- National Park Service, Wildlife Health Center, 2010. "White-nose syndrome" (On-line). National Park Service, Wildlife Health. Accessed September 16, 2010 at http://www.nature.nps.gov/biology/wildlifehealth/White_Nose_Syndrome.cfm.
National NatureServe Conservation Status
Rounded National Status Rank: N3 - Vulnerable
NatureServe Conservation Status
Rounded Global Status Rank: G4 - Apparently Secure
Comments: Roosts in mine tunnels and thus vulnerable to their loss or inaccessibility.
Relevance to Humans and Ecosystems
Names and Taxonomy
Comments: Considered a subspecies of M. WATERHOUSII by Anderson and Nelson (1965) and Hall (1981). Regarded as a distinct species by Davis and Baker (1974) (based on morphometric and karyotypic evidence); Jones and Carter (1976), Honacki et al. (1982), Jones et al. (1986, 1992), and Koopman (in Wilson and Reeder 1993) followed Davis and Baker (1974) in regarding CALIFORNICUS as a distinct species. See Baker et al. (1989) for a classification of the higher categories of New World Phyllostomidae (relationship of the genus Macrotus to other members of the family is uncertain). See Van Den Bussche (1992) for an analysis of phylogenetic relationships of phyllostomid bats based on restriction-site variation in the ribosomal-DNA gene complex (Macrotus regarded as sole member of subfamily Macrotinae).