Mammals
of the
San Gabriel Mountains
of California

The primary objectives of my study were to determine the present mammalian fauna of the San Gabriel Mountains, to ascertain the geographic and ecologic range of each species, and to determine the systematic status of the mammals. In addition, certain life history observations have been recorded.

Field work was done in the north-south cross section of the mountains from San Gabriel Canyon on the west, Cajon Wash on the east; and from the gently sloping alluvum at the Pacific base of the mountains at roughly 1000 feet elevation on the south, over the crest of the range to the border of the Mohave Desert at an elveation of 3500 feet on the north. Camps were established at many points in the area with the object of collecting the mammals of each association and each habitat. Field work was begun in the SanGabriels in November 1948, and was carried on intermittently until March 1952. I was unable to carry on field work in any summer.

For advice and assistance in various ways I am grateful to Drs. Willis E. Pequegnat, Walter P. Taylor, Henry S. Fitch, E.Raymond Hall, Mr. Steven Jacobs, and my wife, Hazel A. Vaughan.

More than 350 mammals were prepared as study specimens; most of these are in the University of Kansas Museum of Natural History. Approximately a fifth of them are in the collection of the Department of Zoology at Pomona College, and a few are in the University of Illinois Museum of Natural History. No symbol is used to designate specimens in the University of Kansas Museum of Natural History. specimens from the Department of Zoology of Pomona Collegef and the University of Illilnois Museum of Natural History are designated by PC and IM, respectively.

Figure 1. Map of the San Gabriel Mountain area showing the positions of places mentioned in the text. [Note by Robert Roy van de Hoek - this map by Terry Vaughn will be included at a future time when the opportunity to scan it arises.]

The San Gabriel Mountains connect the Sierra Nevada with the Peninsular Ranges of southern California and Baja California. On the west the San Gabriel Mountains are bordered by the Tehachapi Mountains, which stretch northeastward to meet the southern Sierra Nevada; to the east, beyond Cajon Pass, the San Bernardino Mountains extend easatward and then curve southward to the broad San Gorgonio Pass, from which the San Jacinto Range stretches southeastward to merge with the Peninsular Ranges.

The rocks comprising the major part of the San Gabriel Mountains probably were intruded in Late Jurassic times, with severe metamorphic activity taking place concurrently.............

The alluvial slopes at the coastal base of the range give way to the foothills at roughly 1800 feet elevation; whereas the Mojave Desert merges with the interior foothills at elevations near 4000 feet.............

Because the San Gabriels stand approximately thirty miles from the Pacific Ocean and are a partial barrier to Pacific air masses sweeping inland, the desert side and the coastal sid of the range differ climatically.

The Californian Biotic Province dominates the biotic aspect of the coastal slope of the range. Thirty-nine out of seventy-two mammals recorded from the San Gabriels are typical of this Province. The coastal sage-flats at the Pacific slope are included in this Province.

Forming a hiatus between the Pacific and the desert slope is the Sierran Biotic Province consisting of coniferous forests on the crest of the range. The chipmunk (Eutamias speciosus speciosus) and the introduced black bear (Ursus americanus californiensis) are the only two mammals which can be considered typical of this area. On the higher peaks of the range, such as Mount San Antonio and Mount Baden Powell, the Canadian Life-zone is represented by certain boreal plants.

At scattered points along the crest of the range and on the desert slope, the Nevadan Biotic Province is represented by the sagebrush scrub association. No mammals can be considered typical of this region.

The Southern Desert Biotic Province occurs below 6000 feet elevation on the interior slope of the range, and markedly influences the mammal fauna of this slope. Twenty-one species of mammals are typical of this Province.

SCIENTIFIC AND COMMON NAMES OF PLANTS MENTIONED IN THIS REPORT
Pinus Lambertiana ..... Sugar Pine
P. monophylla ..... One-leaf Pinyon Pine
P. ponderosa ..... Ponderosa Pine
P.contorta ..... Lodgepole Pine
Pseudotsuga macrocarpa ..... Big-cone Spruce
Abies concolor ...
Libocedrus decurrens ...
Juniperus californica
Ephedra sp.
Bromus sp.
Yucca whipplei
Yucca brevifolia
Salix sp.
Alnus rhombifolia
Castanopsis sempervirens
Quercus kelloggii
Quercus agrifiolia
Quercus dumosa
Eriogonum fasciculatum
Umbellularia californica
Tetradymia spinosa ..... Cotton-thorn
.......... (to be compiled later)

There are several habitats within the coastal sage scrub association. These differ from one another chiefly on the basis of soil type. The soil of the rather level sagelalnd in most places is rocky or gravelly, or , as adjacent to washes, it is finely sandy in texture, and supports the major plants of the association. Most of the eroded adobe banks at the base of the foothills support these same plants, with white sage being the dominant species. Locally, as in damp hollows or cleared areas, there is grassland. Jumbles of boulders, sand, gravel, and steep cutbanks, are characteristic of the channels of dry washes, these areas supporting sparse vegetation. The fauna and flora of the washes are distinct from thsoe of surrounding sage flats. Because they are included within the geographic limits of the coastal sage belt, however, the washes are discussed along with this association.

The abruptness with which one habitat gives way to another in this association causes sharp dividing lines between the local ranges of certain mammals. For example, in trap lines transecting dry washes and level sageland two assemblages of rodents were found. .......

The following list gives the results of about 500 trap nights

The prickly-pear cactus is of obvious iimportance to certain mammals of the coastal sage belt. This cactus is most common in disturbed areas such as sandy flats bordering washes, eroded adobe banks, and land once cleared by man. In these areas it is often the dominant plant with respect to area covered, usually growing in dense patches each covering approximately 150 square feet. It provides substitute nesting sites for Neotoma lepida in areas devoid of rock piles, and is probably the major factor governing the distribution of this wood rat in the sageland. Cottontails and brush rabbits use prickly-pear cactus as refuge. Their forms and short burrows can be seen beneath many of the clumps of cactus.

This cactus serves as food for many mammals at least in the fruiting period in the fall. Usually only the fruit is eaten, but some pads are chewed by rabbits. The fruit or seeds of this plant are eaten by striped skunks, gray foxes, coyotes, pocket mice, kangaroo rats, wood rats, and probably white-footed mice.

The coyote is the dominant carnivore of the coastal sage flats. Many individuals spend the day in the adjacent chaparral-covered foothills and travel down into the flats at night to forage.

In the foothills of the San Gabriels the gray squirrel is restricted to the oak woodland, even though this association may be represented by only a narrow strip of canyon bottom oak trees. The presence or absence of "bridges" of oak woodland between mountains which are centers of gray squirrel populations and nearby ranges has probably been a major factor influencing the present geographic distribution of this animal.

The raccoon is the most abundant carnivore of the oak woodland, being especially common in the riparian habitat.

The chaparral assoication is characterized by tracts of dense brushy plants. These plants are from three to ten feet tall, their interlacing branches often forming nearly impenetrable thickets. Typically little herbaceous growth is present beneath the chaparral, the ground being covered with varying amounts of mull.

The effects of fire, slope, exposure, and elevation, make the chaparral association extremely varied .........

Dipodomys panamintus mohavensis, Neotoma fuscipes simplex, and Peromyscus truei montipinoris are probably the most characteristic mammals of the pinyon-juniper association.

Because of its limited occurrence in the San Gabriel Mountains, this association {there} has relatively little effect on the mammalian dsitribution. Locally, nevertheless, the presence ...............

Although the vegetation of this area is scattered and sparse, presenting a barren and sterile aspect, the area supports a rather high population of rodents. The soil at the bases of many large boxthorn- and creosote-bushes is perforated by burrow systems of Dipodomys panamintus or Dipodomys merriami, and those burrows of abandoned kangaroo rats are used as retreats by Onychomys torridus and Permomyscus maniculatus. The mammals of this association are all characteristic of the fauna of the Mojave Desert, with the ranges of such species as the coyote and jack rabbit extending well up the desert slope of the mountains...............

Near Camp Baldy in the sandy soil beneath the groves of alders moles seemed to be especially abundant. Although common on the coastal face of the range, moles shunned compact, dry, or rocky soils. In the greasewood chaparral one-half mile west of the mouth of Palmer Canyon, where the soil was hard and rocky, mole tunnels were in soft soil that had accumulated at the edge of a fire road beneath a steep road cut. The assumption is that this accumulation contained insects attractive, as food, to the moles.
Specimens examined, 2: Los Angeles County: Camp Baldy, 4200 ft., 1(PC): Claremont, 1600 ft., 1(PC).

Woodland habitats seem to be preferred by evotis. At severall ponds in lower San Antonio Canyon this bat was observed repeatedly as it foraged over the water and coursed low between rows of alders and Baccharis. At Blue Ridge in September, 1951, these bats foraged approximately six feet above the grouond beneath th canopy of coniferous foliage and between the trunks of the trees. .............[to be compiled fully by Robert Roy van de Hoek in the future as time and funds allow].

The series .................................

This bat was collected in San Antonio Canyon from 50 minutes after sundown to two hours and 40 minutes after sundown. In this area these bats did not visit the ponds in large numbers asa they seemed to do on the desert slope.

A female taken on May 29, 1951, contained one embryo nearly at term.

Specimens examined. - Total, 9, distributed as follows: Los Angeles County: .. ..........[to be compiled fully by Robert Roy van de Hoek in the future as time and funds allow]; San Antonio Canyon, 2800 ft., 5.

Hoary Bats are present in the San Gabriels in the fall, winter, and spring. In 1951 the last spring specimen was taken on June 11, in Mescal Canyon; then collecting was discontinued until late September when the first Hoary Bats were recorded regularly. They seemed to be as common in early June as in most of April and May; possibly some remain in the San Gabriels throughout the summer.

In spring these bats seem to segregate by sex; of twelve kept as specimens and at least an equal number captured and released only one was a female. All were captured above 2800 feet.

Hoary Bats seem to have a long pre-midnight forage period, having been captured at ponds from 21 minutes after sunset, to three hours and 26 minutes after sunset. Generally those taken early had empty stomachs and those taken later had full stomachs.

On May 25, 1951, an unusual concentration of Hoary Bats was observed at a pond at about 3200 feet elevation, in San Antonio Canyon (Vaughan, 1953). The day had been clear and warm, one of the first summerlike days of spring. Beginning at 30 minutes after sundown hoary bats were collected until two hours and 35 minutes after sundown; in this period 22 were caught and at least as many more observed. Many were released after being examined, whereupon they hung on the foliage of nearby alders to rest and dry themselves. This concentration of Hoary Bats may have been due to a sudden beginning of migration with a resultant concentration of bats at certain altitudinal belts. The warm weather might have set off the migration. On evenings that followed the subsequent hot days no such concentration of Hoary Bats was seen. B.P. Bole (Hall 1946:156) observed a concentration of Hoary Bats on August 28, 1932, Esmeralda County, Nevada.

Several captive Myotis californicus in a jar next to a pond in San Antonio Canyon set up a squeaking which seemed to attract a Hoary Bat. Repeatedly the large bat swooped over the jar.

Specimens examined. - Total, 12, distributed as follows: Los Angeles County: Mescal Canyon, 4900 ft., 2; San Antonio Canyon, 3200 ft., 2; San Antonio Canyon, 2800 ft., 8.

Coyotes catch many jack rabbits and regularly forage around the foothillls borders of the citrus groves for cottontails and jack rabbits.

A female examined on February 15, 1951, was pregnant, and one taken on March 15, 1951, carried three small embryos.

The population seemed to be at a low ebb from 1948 to 1952, when field work was done on the desert slope. I often hiked for an hour or more on the desert or juniper-covered benches without seeing a jackrabbit. The species was commoner in washes where as many as eleven were noted in two hours' hiking.

In December, 1951, below Graham Canyon, the leaves on large areas of many nearly recumbent Joshua trees had been gnawed down to their bases, and jack rabbit feces covered the ground next to these gnawings. Probably the Joshua tree is an emergency food used by the rabbits only when other food is scarce.

In years when the population of jack rabbits is not low they serve as a major food source for coyotes. In the Joshua tree belt below Mescal Canyon, jack rabbit remains were fairly common in coyote feces, and tracks repeatedly showed where some coyote had pursued a jack rabbit for a short distance. A large male bobcat trapped in the juniper belt in Graham Canyon had deer hair and jack rabbit remains in its stomach.
Specimens examined. - Total, 7, distributed as follows: Los Angeles County: 6 mi. E and 1 mi. S Llano, 3500 ft., Mescal Canyon, 4800 ft., 3.

Cottontails are seldom above the sage belt in the chaparral associations, although along firebreaks and roads they occasionally occur there. Habitually cottontails escape predators in partly open terrain offering retreats such as low, thick brush, rock piles, and cacatus patches; but on open ground beneath dense chaparral, cottontails may be vulnerable to predation.

Examinations of feces and stomach contents of the coyote reveals that it preys more heavily on cottontails than on any other wild species. Remains of several cottontails eaten by raptors were found in the sage belt.

In April, 1951, many young cottontails were found dead on roads in the sage belt, and a newly born cottontail was in the stomach of a coyote trapped four miles north of Claremont, on February 7, 1952.

In the pinyon-juniper association cottontails and jack rabbits probably occur in roughly equal number, but in the Joshua tree belt cottontails seem.............

The ecologic niche of the brush rabbit is in brush where the platns form continuous thickets with little open ground. In the coastal sagebrush flats, area s supporting only scattered bushes are uninhabited by brush rabbis, while areas grown to extensive tracts of brush harbor them. When the brush rabbit's mode of escape from enemies is considered, the reason for their habitat preference becomes more clear..............................

A great horned owl shot in March, 1951, in the sage belt, had in its stomach the remains of a freshly killed adult brush rabbit. Althoug coyuotes and brush rabbits often occur in the same general sections..................

In Live Oak Canyon in December of 1950, tracks indicated thatt a bobcat had killed a gray squirrel in a small draw beneath the oaks. In Evey Canyon on March 6, 1951, while watching for bats at late twilight, I observed a gray squirrel traveling through the branches of a nearby oak. A great horned owl glided into the oak in an attempt to catch the squirrel, which leaped quickly into a dense mass of foliage and escaped. For roughly ten minutes the owl perched in the oak watching its intended prey, then flew off down the canyon amid frantic scolding by the squirrel.

On March 17, 1951, a female gray squirrel taken at about 3500 feet elevation in San Antonio Canyon contained two embryos, each roughly 40 millimeters long.

No squirrel was seen in December, January, and February, indicating that all were below ground in winter.
Specimen examined. - San Bernardino County: Desert Springs, 4000 ft., 1 (PC).

Although observed less often in winter than in summer, this species is active all year. On February 6, 1949, in Mescal Wash, an antelope ground squirrel was foraging over the snow which was at least six inches deep. these squirrels were attracted to the carcasses of rodents used as bat for carnvore sets, and caused a good deal of trouble by disturbing the traps.

Antelope ground squirrels used the topmost twigs of box-thorn bushes extensively as lookout posts, and many of their burrows were at the bases of these thorny bushes. This habit of regularly using observation posts is well developed in each species of ground squirrel found in the San Gabriels.

On Blue Ridge these chipmunks used the uppermost stems of snowbrush as vantage points, and when disturbed ran nimbly over thorny surfacs of the brush in seeking refuge in the tangled growth.

In early November of 1951, these animals were not yet in hibernation on Blue Ridge. They were noted on November 6, after the season's first snows had melted; on November 13, however, a cold wind with drifting fog kept most of them under cover, and only two were noted in the course of the day.
Specimen examined.-Los Angeles County: 1 mi. S and 2 mi. E Big Pines, 8100 ft., 1.

On the desert slope merriami was partial to rocky areas in teh pinyon-juniper association but was also in the black oak woods on the Ball Flat fire road near Jackson Lake. Nowhere was and E. speciosus observed on common ground.
Specimens examined.-Los Angeles County: San Antonio Canyon, 5500 ft., 2 (1 PC).

In the vicinity of Big Pines, on the interior slope, gophers preferred broken forest where snow brush or other brush occurred, their workings, however, were also found beneath groves of conifers and black oaks. The abundance of earth cores resting on the duff indicated that this species is active in the snow in winter.

The cheek pouches of many specimens taken in early winter contained the green shoots of grass and little dry material. On many occasions rat traps set next to wood rat nests beneath large junipers produced panamintus, and many of these animals had their cheek pouches crammed full of juniper berries.

In December, 1948, panamintus was trapped consistently on nights when the temperature dropped to below 20oF. On December 27, 1948, after a three inch snowfall, tracks of this species were noted in the snow at the mouth of Mescal Canyon.

Parts of the skulls of this species were found in many coyote feces from the desert slope.

The coyote probably is one of the major predators of these kangaroo rat; remains of this rodent were often found in coyote feces, and coyotes excavated many burrow systems in large kangaroo rat coloies in the sandy ground near San Antonio Wash. The soil there is so soft that coyotes probably were often succssful in digging out their prey. The shed skin of a large Pacific rattlesnake (Crotalus viridis helleri) was found four feet inside the mouth of a kangaroo rat burrow; probably this reptile preys on agilis. Great Horned Owls (Bubo viirginianus pacificus) come down nightly from the chaparral to hunt in the sage flats. Beneath the perches of these owls I have found pellets containing bones of agilis.
Specimens examined.-Total, 13, distributed as follows: Los Angeles County: San Antonio Wash, 1900 ft., 11 (10 PC); 4 mi. NE Claremont, 1600 ft., 2.

Specimens of D. agilis from the desert slope two miles east of Valyermo are referrable to the subspecies perplexus. A series taken in Cajon Wash at Devore, on the Pacific slope, is intermediate between agilis, of the coastal slope of the San Gabriels, and perplexus of the desert slope, but approaches more nearly the later subspecies. Thus, different subspecies of D. agilis on opposite slopes of the San Gabriel Mountains, with integradation taking place in the Cajon Pass area and probably also at the west end of the Mountains.

Both scrub oak acorns and juniper berries were found in the cheek pouches of this subspecies, and one immature individual taken in Swarthout Valley had its cheek pouches stuffed with approximately 550 seeds of brome grass.

On November 13, 1951, at 7500 feet on Blue Ridge, a small juvenile was taken; it must have been born not earlier than September.

Specimens examined.-Total, 17, distributed as follows: Los Angeles County: 2mi. E Valyermo, 4600 ft., 3; 5 mi. E Valyermo, 1; 1 mi. E Big Pines, 6600 ft., 6; 1 mi. S and 2 mi. W Big Pines, 7400 ft., 2. San Bernardino County: Cajon Wash, 1/2 mi. SW Devore, 2200 ft., 5.

Those specimens of harvest mice from near Big Pines may be grading toward the desert race megalotis; my series of specimens from this locality, however, is too small for clear indications on this point.

Individuals in juvenal pelage were taken on November 26, 1951, near Devore.

Specimens examined.- Total, 6, distributed as follows: Los Angeles County: 1 mi. E. Big Pines, 6600 ft., 2; Palmer Canyon, 2000 ft., 1; 4 mi. N Clarment, 1700 ft., 3 (PC).

Specimens examined. Total, 6, distributed as follows: Los Angeles County; Mescal Wash, 4000 ft., 10 (4 PC).

In the coastal sage belt these woodrats are restricted to wash areas where large chaparral plants such as lemonadeberry and laurel sumac are used as nesting sites. In San Antonio Wash the occasional large juniper trees almost invariably harbor the nests of fuscipes. The general absence of suitable nesting sites .........
Specimens examined. Total, 4, distributed as follows: San Bernardion County: Icehouse Canyon, 5500 ft., 2. Los Angeles County; San Antonio Canyon, 2800 ft., 2.

A raccoon freed from a small steel trap in San Antonio Canyon concealed itself in an unusual but extremely effective manner. When released the coon splashed up the middle of the small creek nearby to a placee where some dead alders had fallen over and shaded the water - here the animals squatted down in the stream. The racoon was mostly submerged, its tail was floating, and its back and the top of its head and snout were above water. With most of its body under water, and with the maze of alder logs above casting a broken pattern of light and shade, it was well hidden....................

In the autumn of 1951, raccoons fed on grapes at the Sycamore Valley Ranch one mile south of Devore....

In the autumn of 1950, at my house near the mouth of Palmer Canyon, a family of spotted skunks lived under the floors............

Wildcats are most common in the chaparral belt where they forage widely from the ridges down into the canyons. Judging from trapping records bobcats are not so common here as the gray fox.

Bobcats occur in the sage belt, where they are most common in the broken country around washes and in brushy areas. Although bocats and coyotes occupy the same general areas here, the habitat preferences of these animals seem to be different, wth coyotes occupying more open country. An indication of the hunting habits of bobcats is furnished by the occurrence of masses of prickly-pear thorns beneath the skin of the legs, particularly the forelegs, of three specimens trapped in the sage belt. These thorns probably were acquired while the bobcats foraged for woodrats or cottontails in the patches of prickly-pear, which are locally abundant in the sage belt.

On March 12, 1951, a small subadult female bobcat, trapped at 4000 feet in San Antonio Canyon, was found dead in the trap and had numerous deep cuts around its head and shoulders, and severe bruises on the right shoulder. The spacing of the cuts, and the tracks around the set, indicated that while held in the trap this animal had fought with a second bobcat that had inflicted the fatal wounds. It seems unlikely that the fight was caused by a male attempting to copulate with the female held in the trap, for the female was found to be carrying an embryo.

In Live Oak Canyon, in December, 1950, tracks and bits of fur indicated that a bobcat had killed and eaten a gray squirrel. Remains of cottontails were found in the stomachs of two bobcats. All six bobcats from the Pacific slope had nematode worms in the pyloric end of the stomach.

Remains of deer were in two of the bobcat stomachs, and one of these stomachs also contained jackrabbit remains. Approximately a dozen nematodes (stomach worms) were in the stomach of one of the larger male specimens.

Grinnell, H.W. 1918. A synopsis of the bats of California. University of California Publications in Zoology, 17:223-404, plates 14-24, 24 figures in text.

Grinnell, J. 1908. The biota of the San Bernardino Mountains. University of California Publications in Zoology, 5:1-170, 24 plates.

Grinnell, J. 1933. Review of the Recent mammal fauna of California. University of California Publications in Zoology, 40:71-234.

Grinnell, J. Dixon, J. and Linsdale, J.M. 1937. Fur-bearing mammals of California . . . University of California Press, 2 volumes, xii + 375 pages, plates 1-7, figures 1-138, xiv + 377-777 pages, plates 8-13, figures 139-345.

Grinnell, J., and Swarth, H.S. 1913. An account of the birds and mammals of the San Jacinto Area of southern California with remarks upon the behavior of geographic races on th margins of their habitats. University of California Publications in Zoology, 10:197-406, plates 6-10, 3 figures in text.

Willett, G. 1944. Mammals of Los Angeles County. Los Angeles County Museum Science Series, Number 9, Zoology Number 4, 26 plates.

Transmittted July 20, 1954.

The San Gabriel Mountains were analyzed for the presence of 53 species of native (natural) mammals and two non-native (alien) mammals (Sierra Nevada Black Bear and Virginia Opossum) by Terry Vaughan in 1954. However, I would list the total mammal species at 56 for the San Gabriel Mountains, three more than recorded by Terry Vaughan. He did not list the Pronghorn Antelope, Grizzly Bear, and Jaguar as part of the original and genuine mammal fauna. These three mammals could be found in the San Gabriel Mountains in the 19th and early 20th Century. The Jaguar went extinct first in the 1830s-1840s. Next, the Pronghorn Antelope went extinct by the 1890s. Lastly, the Grizzly Brown Bear went extinct by the 1920s. From the 1920s onward, no mammals have gone extinct in the San Gabriel Mountains. It is not an oversight by Terry Vaughan that he did not list these three mammals as he was doing work on the extant fauna of the 1950s. He did make a comment about the Grizzly Brown Bear having been in the San Gabriel Mountains just prior to the alien introduction of the Black Bear. Terry Vaughan was trained as a mammalogist and published his research in the respected scientific journal of the University of Kansas. Ultimately, I will completely edit, compile, and provide further analysis of the very fine monograph by Terry Vaughan. It will be the 50th anniversary of his publication in 2004, so it seems a good time to plan to have his monographic report on the mammals completely ready for viewing on the internet at that time. However, at this time, I have provided you with excerpts to entice naturalists, environmentalists, visitors, scientists, and hikers to be more knowledgeable about the San Gabriel Mountains. I am motivated to do this internet web site because of my fascination and curiosity for the San Gabriel Mountains. In addition, I am motivated by my interest to draw the attention of the Sierra Club-Angeles Chapter toward a more wildlife-science and conservation biology focus regarding the San Gabriel Mountains. Consequently, I would like to acknowledge all those outings folks in the Sierra Club who love to hike and explore, as do I, in the beautiful San Gabriel Mountains.

Under discussion of "Biotic Provinces and Ecologic Associations" Terry Vaughan noted accurately that the Black Bear is an alien invasive exotic species of the San Gabriel Mountains by using the term "introduced." The Black Bear is having a negative impact on the native plants and native animals that live in the San Gabriel Mountains. These bears need to be captured alive without harm and transplanted back to the Sierra Nevada from where they originally were captured and transported in cages by truck. The only bear that is native (natural) to the San Gabriel Mountains is the Grizzly Brown Bear. Therefore, when Terry Vaughan states: "The chipmunk and the introduced black bear are the only two mammals which can be considered typical of this area" he made a mistake because the bear is non-native and is thus not to be considered in the evaluation. Therefore, only one mammal, the chipmunk, Eutamias specious specious, is genuinely characteristic of only the San Gabriel Mountains.

As to the native charismatic megafauna, the Desert Bighorn Sheep and Mountain Lion are still found in the San Gabriel Mountains. Some members of the diminutive mesofauna, such as the Raccoon and Striped Skunk have adapted behaviorally to an urban environment, which was noted by Terry Vaughan already 50 years ago.

For me, as the compiler of this fine publication of Terry Vaughan, the most important natural history discovery was that the Northern Flying Squirrel is suspected, but not substantiated, to be in the San Gabriel Mountains. Terry Vaughan was not able to capture or document a specimen. He was only able to see some ecological evidence by observing pine cones that were eaten, and using logic that the likely absence of Western Gray Squirrel in the vicinity of Big Pines meant that there must be Flying Squirrel there. He suggested that focused field work in this area may reveal the presence of the Northern Flying Squirrel. I wonder if anyone has done that field work or made any natural history observations as suggested 50 years ago by Terry Vaughan. I have it in my mind to go to the Big Pines area and see if whether I position myself there for several days to a week or more, and stay up at night to watch, whether I would be able to document the Northern Flying Squirrel. Someday, when time and money allow me that luxury, I may just do that. It seems that the well-documented presence in the San Bernardino Mountains, that they at least once upon a time, perhaps back in the Pleistocene Ice Age of 10,000 years ago, must have occurred in the San Gabriel Mountains. Did climate, Native Americans, modern Europeans, other mammal carnivore predators, or lack of food resources finally cause the local extirpation of the Northern Flying Squirrel in the San Gabriel Mountains. Or, is the Northern Flying Squirrel still extant in the San Gabriel Mountains but just escaping detection by scientist-naturalists?

I also found the discussion by Terry Vaughan regarding the Hoary Bat to be quite fascinating. Terry Vaughan also published a separate article about this bat in the Journal of Mammalogy. I wonder if his solid descriptive narrative about the Hoary Bat has any relevance to the endemic and rare Hawaiian Hoary Bat. I suspect that there is at least a tid-bit of knowledge of the natural history observations of Hoary Bat by Terry Vaughan that can be applied to the Hoary Bat of Hawaii. It is fascinating to me consider the linkage of California's San Gabriel Mountains of Los Angeles to the mountainous islands of Hawaii. It seems likely that the Hoary Bat of Hawaii flew there during a summer-autumn south-bound migration from the north while heading south to California. It does not seem likely that it was during the spring northward migration, but one cannot say. It is also of interest to consider that the first Hoary Bats of Hawaii may have been carrying seeds/spores of plants/ferns, or even insect eggs on the feet, or in the stomach. Apparently, there is only this one native bat in Hawaii and it is the Hoary Bat. The Hoary Bat is an especially narrow-winged bat and is a well known migratory species which explains how it is the most likely candidate of California's 12 (one dozen) species to colonize the Hawaiian Islands, which are about 2,300 miles (3,700 kilometers) away from North America. An interesting analogy is with a very narrow-winged bat, Leisler's Bat, which reached the Azores Islands at a distance of 930 miles (1,500 kilometers) from Europe, a long time ago.

The narrative style in the natural history accounts is quite fascinating. Such passages as regards the Western Gray Squirrel being preyed upon by the Bobcat and the Great Horned Owl are worth reading about and is good that he presented them to us. Also, the passage of the Antelope Ground Squirrel being found travelling over snow and using look-out posts of Boxthorn are excellent natural history observations.

After reading about the Antelope Ground Squirrel, I recalled my experiences with the San Joaquin Antelope Squirrel on the Carrizo Plain in San Luis Obispo county. And I think about how the Pronghorn Antelope has been recovered there, so that now there are two animals with "antelope" in their name. I now wish to share with you that the Pronghorn Antelope would also have been a part of the mammalian fauna of the desert slope of the San Gabriels, at least within the Joshua tree woodland. I wonder why Terry Vaughan did not discuss the Antelope, while he did make a brief statement that the Grizzly was in the San Gabriels.

Some specifics as to ecology are very interesting to consider from Terry Vaughan's writings. For example, under the California Meadow Mouse, he states: "Owing to the paucity of extensive areas of grassland in the San Gabriels, this is one of the least common rodents of the area." This passage can now be elaborated on as follows: Grasslands that are wet and thus meadows as indicated in the name of the mouse. These grasslands have soils to shallow and sterile to support chaparral and forest and so in turn become meadow grasslands with several kinds of wildflowers. These meadows are usually on fairly level surfaces but not exclusively. They are one of the rare wetland types of the San Gabriel Mountains. There is no way for humans to increase these meadows in size, nor should he. The meadows must remain natural with no alteration to these landscapes. More on all this discussion at a later time.