Northern Saw-whet Owl Owls and Nightjars Northern Saw-whet Owl Aegolius acadicus Owls and Nightjars Daniel Fitzgerald

Wildflower Mount Diablo Thimble Clover Scientific Name: Trifolium microdon Family: Fabaceae (Pea Family) Blooms: Color: White Annual Herb Native, and endemic (limited) to California Jump to Blooming Now Blue / Purple Red / Pink White Yellow / Orange Invasive Plants

Wildflower Mount Diablo Royal Larkspur Scientific Name: Delphinium variegatum ssp. variegatum Family: Ranunculaceae (Buttercup Family) Blooms: Mar - Jun Color: Blue-Purple Perennial herb Native, endemic to California Jump to Blooming Now Blue / Purple Red / Pink White Yellow / Orange Invasive Plants Kevin Hintsa

Say's Phoebe Flycatchers Say's Phoebe Sayornis saya Winter Flycatchers Daniel Fitzgerald This flycatcher is grayish brown with a dark tail and a orange buffy breast.

Tarantulas on Mount Diablo October 1, 1998 Mike Woodring Why are tarantulas out wandering about? Late summer and fall is tarantula time on Mount Diablo. The tarantula (Aphonopelma sp.), North America’s largest spider, is nocturnal and spends most of its life in and around its underground burrow. However, when a male tarantula reaches maturity at about four to seven years of age, he sheds his exoskeleton for the last time, develops little spurs or hooks on his front legs, and leaves his subterranean home for good to risk life and limb (all eight of them) in search of females of his species with which to mate. These males are the autumnal wanderers we see on the mountain. After a male locates a female by scent, he gently taps at the entrance to entice her out of her burrow to mate. He uses the small clasping hooks on his front legs to hold her fangs and bend her backward. Mating lasts from 30 seconds to a couple of minutes. After mating, the larger, longer lived female (she may live to the ripe old age of 20 years or more) returns to her burrow, ultimately to hatch a hundred or so baby spiders the following spring, of which perhaps one or two spiders will survive to adulthood. It’s not easy being a tarantula. Will a female tarantula eat the male? It’s a myth that female tarantulas always kill the males after mating. On rare occasions, a female that has already mated several times and is approached by an amorous male may attack and eat the male rather than mate again. A female may consume the male if she is famished and needs a meal to be able to lay eggs, but almost always she allows the male to retreat to continue searching for other females until he succumbs to the elements in a few weeks, due to the onset of cold weather, starvation, or the jaws of a predator. Note to parents: A wandering tarantula won’t live long enough to make a good pet. What do tarantulas eat? Typically, a hunting tarantula waits patiently in its burrow near the opening until an unsuspecting insect (usually a cricket) crawls by. The spider rushes out, bites the prey, and drags its victim back into the burrow. In the dark of night, this activity goes unnoticed (except by the cricket!). Why do some tarantulas have a bald spot? The tarantula’s main weapon against larger creatures is defensive. If a bobcat or fox is harassing it, the spider rises up on its front legs and with its back legs scrapes off a cloud of barbed, porcupine-like hairs from its abdomen into the nasal passages and mucous membranes of its tormentor. This tactic sometimes gives the tarantula time to escape and is why a tarantula may sport a bald spot on its abdomen. Who is its most feared predator? The large black and orange female tarantula hawk wasp (Pepsis sp.) seeks out and attacks the tarantula. After delivering a paralyzing sting under a leg, the wasp drags the tarantula to a hole and, before covering the tarantula, she lays a single egg on the helpless spider. When the egg hatches, the young wasp larva eats the tarantula alive. How bad is a tarantula’s bite? Despite its fearsome appearance and formidable reputation, the tarantula is really a rather innocuous creature–a terror to small insects and not much else! Tarantulas have very small venom glands, and its very mild venom is only strong enough to paralyze a cricket, with practically no effect on people. Mount Diablo’s tarantulas are really gentle souls that play an important part in the web of life on our island mountain. So the next time you encounter a tarantula on the trail, remember the old adage, “If you wish to live and thrive, let a spider run alive!” Download Tarantulas: Protect These Gentle Giants Brochure (pdf) BACK TO LIST

Yellow-rumped Warbler Warblers Yellow-rumped Warbler Setophaga coronata Winter Warblers Daniel Fitzgerald Daniel Fitzgerald Can be found at almost any wooded habitat, and low brushy areas, and in weedy fields. There are two subspecies – Audubon’s (S. c. auduboni) and Myrtle (S. c. coronata) which hybridize. Key features are white wing bars, yellow rump and yellow at sides of breast. The throat color of Audubon’s is yellow and Myrtle is white. Females are duller. The ‘chip’ call note can be heard throughout the winter and is required learning for all serious birders; once learned it becomes easy to locate other warblers simply by listening for a different sounding call note. Mostly eats insects, but also fruit or nectar.

Red-shouldered Hawk Diurnal Birds of Prey Red-shouldered Hawk Buteo lineatus All Year Diurnal Birds of Prey Daniel Fitzgerald A truly red hawk with rufous shoulders, wing linings and underparts contrasting with black and white bands on wings and tail.

Steller's Jay Jays and Crows Steller's Jay Cyanocitta stelleri All Year Jays and Crows Daniel Fitzgerald Frequents coniferous and mixed coniferous-deciduous forests; typically inhabits more densely forested areas than open woodlands and scrub-like habitats of the Western Scrub Jay . A stunning, deep blue over most of plumage, darkest on head and face. Also sports a distinctive crest. Listen for its loud, repetitive cries, in woodlands and forests; sometimes imitates the calls of hawks. Its bulky, cup-shaped nest is constructed in trees from twigs, leaves, and mud. An omivorous feeder, its diet of plant and animal matter is widely varied.

Mitchell Canyon is a Great Place to Hike by Dan Sandri Oh, the Species You Can See! January 1, 2024 Mount Diablo Globe Lily by Dan Sandri Mitchell Canyon, on the north side of Mount Diablo State Park, features varied habitats with a great diversity of plants and animals. This includes uncommon-to-rare species, disjunct populations (populations separated from other populations of the same species, often by great distances), and endemic species (species not found elsewhere). Near the soon-to-be Mitchell Canyon Education Center, Mitchell Creek winds through riparian habitat, chaparral, oak woodland, grassland, and some pine forest. Each of these habitats has its own population of plants and animals that may not be found in the others. Below, MDIA Board member Dan Sandri features a few fascinating plants and animals that are found along Mitchell Creek. Mount Diablo Globe Lily, aka Mt. Diablo Fairy Lantern (Calochortus pulchellus) is a rare species of flowering plant in the lily family known by the common name Mt. Diablo fairy-lantern or Mount Diablo globelily. The Mt. Diablo fairy-lantern is endemic to California, and is mainly restricted to Mount Diablo of the Diablo Range. There are historical occurrences in the North California Coast Ranges, within Marin, Solano, Napa, and Humboldt Counties. Mitchell Canyon is a prime location to see this beautiful flower. Complex Physocephala marginata (Family Conopidae): Physocephala marginata is a species of thick-headed fly (or complex of very similar species) in the family Conopidae. These flies are endoparasitoids during their larval stages. Hosts include mainly wasps and bees. They possess a ventral genital plate that is used to pry apart the abdominal sclerites of the host bee or wasp for egg insertion; eggs are deposited in the abdomen by females. After the host dies, an adult Conopid fly emerges from the dead insect. California Bumble Bee (Bombus californicus) is a mid-sized bumble bee that is very uncommon on Mount Diablo. It can be seen occasionally in Mitchell Canyon. It is mostly black in color, with black between wing bases and yellow hair in front of the wing bases. It has a black face (no yellow hairs on face). Its 4th abdominal tergum is always yellow. The California Bumble Bee is a flower generalist, and on Mount Diablo has been documented on hedgenettles, Western Wallflower, thistles, lupines and Pacific Pea. This is a dark bumble bee and thought by some to be a subspecies of Bombus fervidus. Eusocial, they nest primarily underground in abandoned rodent nests, or sometimes in grass just above ground. Thought to have suffered from competition with other bumbles, such a B. vosnesenskii. A Fishfly - (Neohermes filicornis) These fishfly adults are sometimes seen at lights at places such as the Mitchell Canyon Visitor Center. These eye-catching critters belong to a small group of insects called the Megaloptera, or fishflies. While most fishflies are remarkable for their large size, this species is extra cool for its stream-inhabiting larvae, sometimes known as hellgrammites, that take 3–4 years to develop. The larvae in Mitchell Creek often have to endure cycles of stream drying, and they do so by burrowing into the streambed. Males like the one shown here have bead-like antennae. In females, the antennae are narrower, smooth, and hair-like. Gorgon Copper (Tharsalea gorgon) Males have a coppery-brown upperside with bright reddish-purple tinge; females are lighter copper, with cream and black spots (this is a female). Eggs are laid singly on host flower stalks and hatch the next spring. Caterpillars eat leaves of buckwheat plants. These butterflies have one flight from May-June. Range: Southern Oregon through California to Baja California. Wide-striped Painted-Dark Bee (Stelis laticincta, Family Megachilidae) is an uncommon species of cleptoparasitic cuckoo bee in the family Megachilidae. The description comes from the cuckoo bird-like behavior of many distinct bee lineages in which females, instead of constructing their own nests and collecting their own pollen, lay their eggs inside the nest of a different pollen-collecting bee species. A cleptoparasitic larvae is one that primarily derives nutrition by consuming the host's food (the pollen ball), rather than deriving nutrition from consuming the host. Stelis laticincta is a cuckoo resin bee - its host is a resin bee in the leafcutter genus Megachile. This bee species appears restricted to the pacific region of the western United States. Its name, laticincta, means "wide-belted," referring to the broad black and yellow stripes of the bee. Checker Lily (Fritillaria affinis affinis) aka Rice-grain missionbells has a leafy flowering stalk that reaches up to 4 ft. and carries one to twelve, pendent, cup-like flowers. The flowers are checkered with brown and green, sometimes with purple and yellow inside. Plants may skip a year or two from flowering, making only a single, broad, tongue-shaped basal leaf during those times. This plant is found from Southern British Columbia, south on both sides of the Cascades in Washington, on the west side in Oregon, to Southern California. California Pocket Mouse (Chaetodipus californicus) is a rarely seen nocturnal rodent that inhabits the chaparral and grasslands of Mount Diablo and feeds mainly on seeds. This specimen was seen and photographed by Dan Fitzgerald while he was leading his monthly Birds, Butterflies and Blooms hike in Mitchell Canyon. This pocket mouse, named for the external pockets they have in their mouth for grain carrying, is found in California from the San Francisco Bay area south into Baja California. It is also found in California’s Sierra foothills. There are eight subspecies. Gray foxes (Urocyon cinereoargenteus) are the only foxes native to the Bay Area, and are about the size of a small-medium dog (about 8-10 pounds on average), with shorter legs and a longer torso than the non-native red fox. They have a long tail with black on the top and a black tip (red foxes have white tail tips). Gray foxes have peppery gray coats with some red/brown highlights. If you see a fox on Mt. Diablo, it will probably be a gray fox, and you will likely see it in the early morning or evening, as Gray foxes are secretive, crepuscular and nocturnal. Gray foxes are thought to have evolved millions of years before other foxes. Equipped with strong, hooked claws, gray foxes climb high into trees to hunt squirrels and to avoid predators, such as coyotes. FYI: red foxes are not tree climbers. Gray foxes also eat rodents, rabbits and birds. A gray fox pair may mate for life, and they can live to be 6-10 years of age. Pups are born in the Spring and are on their own in 9 months. Will you join us in helping to build the new Mount Diablo Education Center, so that for the first time, school buses can safely bring students from any neighborhood in Contra Costa County to experience the mountain? Donate today at: https://www.mdia.org/donate Complex Physocephala marginata (Family Conopidae) DSandri California Bumble Bee (Bombus californicus) DSandri Fishfly DSandri Checker Lily (Fritillaria affinis affinis) DSandri Gorgon Copper (Tharsalea gorgon) DSandri Wide-striped Painted-Dark Bee (Stelis laticincta, Family Megachilidae) DSandri California Pocket Mouse (Chaetodipus californicus) DFitzgerald Gray foxes (Urocyon cinereoargenteus) DSandri Mitchell Canyon Education Center Entrance BACK TO LIST

Wildflower Mount Diablo Slender Centaury Scientific Name: Centaurium tenuiflorum Family: Gentianaceae Blooms: June - Aug Color: Red-Pink Annual herb Introduced Jump to Blooming Now Blue / Purple Red / Pink White Yellow / Orange Invasive Plants Daniel Fitzgerald

Hermit Thrush Thrushes and Thrashers Hermit Thrush Catharus guttatus Winter Thrushes and Thrashers Daniel Fitzgerald It is not uncommon to see this bird on the side of a woodland trail during migration and winter; but it may also frequent chaparral, scrubby areas, or other habitats with dense undergrowth. Olive-brown or grayish-brown back and head typically contrast with rufous tail; also, tail is occasionally quickly raised and slowly lowered. Compare with Swainson’s Thrush . Diet includes insects, small amphibians or reptiles, and fruits.

Tarantulas: The Gentle Giants of Mount Diablo by Michael Marchiano October 1, 1998 Michael Marchiano Each year in late summer, male tarantulas born between four and seven years ago find a secluded place and lay down a sheet of silk webbing. Resting on top of the silk, they split their outer skin covering the thorax and, over several hours, slowly extract their legs and slough off their old skin. This is their final molting. This new adult male tarantula is an exact replica of the prior one except he now possesses “nuptial” hooks on his fore legs to use in mating over the next couple of months. From mid August to late October, the East Bay area male tarantulas (Aphonopelma iodius ) will be on the prowl. Their counterparts, the females, will be staying at home in burrows where they have lived for as long as twenty-five years. The females also reach maturity after between four and seven years, and it is unknown whether they mate every year. In fall, those that wish to mate will clean out the entrances to their burrows and cover them with a thin silk cover. The amorous males, who may wander as much as a mile while searching for a female's burrow, are probably attracted by some form of pheromone. When located, the males tap out a message on the silk explaining their mating intentions, assuring the female they are not a threat nor should she consider them a meal. As the female comes out of the burrow, the male will back up and allow her to approach, touching legs. The male then cautiously bends the female backwards using the hooks on his front legs to hold onto her fangs while mating. Mating may last from thirty seconds to three minutes and before the male releases the female, wandering off while she returns to her burrow. For the next two months, the male will continue looking for other females to mate with, growing weaker and finally dying as winter approaches. The female will overwinter in her burrow, occasionally coming out at night to capture a meal. In late winter to early spring, the female will weave a silk pillowcase in which she will lay 100 to 150 tiny eggs. She will care for the eggs for approximately 30 days, at which time she tears a small slit in the egg case and the tiny white pinhead-sized spiderlings hatch out. Within a few days, the spiderlings will molt, shedding their exoskeleton for the first time. They disperse immediately since they are susceptible to many predators, including each other. Over the next four to seven years, the survivors living in their separate burrows will molt and grow, feeding at night and hiding during the day. North American tarantulas have a very mild venom that can easily paralyze a small arthropod but it is totally harmless to humans. They do possess tiny barbed hairs on their abdomen that can be sluffed off into an attacker’s face, causing itching and watery eyes. Hollywood and the media have made tarantulas seem monstrous, so to many people these slow-moving spiders appear ominous and threatening. Nothing is farther from the truth; they are truly one of the gentle giants of the animal world. BACK TO LIST