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Spotted Towee by Jenn Roe Marvelous Animal Adaptations May 21, 2025 by Dan Fitzgerald The Spotted Towhee is an eye-catching bird, but it takes some luck to see one. Bright white dots decorate black wings and back; rufous (reddish) sides stand out against a white belly; a jet black head holds intense red eyes. Believe it or not, this striking bird is designed to hide, which is what it does in a brushy habitat where its colorful patterns blend with the dappled shade. Chaparral and open woodlands provide the Spotted Towhee with the shrubs it needs for protective cover and a year-round food supply. An omnivore , eating from both plants and animals, the Towhee forages by hopping around and scratching the ground for insects, spiders, millipedes, and other nourishment. It also searches low limbs for food. In fall and winter, when insects disappear, Towhees dine on seeds and berries. The Spotted Towhee’s secretive life in the brush changes in spring when the male bird perches conspicuously atop shrubs to sing his raspy song either to attract a mate or declare his territory (keep out!). Why does the female have such drab feathers? The female Towhee spends most time on the ground. Her dull, ground-colored feathers help her go unnoticed by predators (such as hawks, owls, and snakes). Towhees nest on the ground or in low branches and the female is the nest builder. She also incubates (sits on) the eggs without any help from her mate. However, once eggs hatch, both parents work to feed the nestlings (baby birds). Download this article by Arnold Joe The Spotted Towhee’s black and white patterns help it blend in the shade of its habitat. The bird pictured above is male. by Arnold Joe In springtime, male Spotted Towhees can be seen singing from the tops of shrubs. by Arnold Joe The female’s dull colors help her blend with the ground, making her less visible to predators while nesting. BACK TO LIST

Wildflower Mount Diablo Fremont Bush Mallow, Diablo Mallow, White Coat Mallow Scientific Name: Malacothamnus fremontii Family: Malvaceae Blooms: Jun - Aug Color: Red-Pink Shrub Native, endemic to California Jump to Blooming Now Blue / Purple Red / Pink White Yellow / Orange Invasive Plants Mike Woodring

Wildflower Mount Diablo Mayweed, Stinking Chamomile Scientific Name: Anthemis cotula Family: Asteraceae (Sunflower Family) Blooms: May-Sep Color: White Annual herb Introduced Jump to Blooming Now Blue / Purple Red / Pink White Yellow / Orange Invasive Plants Daniel Fitzgerald Daniel Fitzgerald

Wildflower Mount Diablo Common Groundsel Scientific Name: Senecio vulgaris Family: Asteraceae (Sunflower Family) Blooms: May - Jun Color: Yellow-Orange Annual herb Introduced Jump to Blooming Now Blue / Purple Red / Pink White Yellow / Orange Invasive Plants Steve Beatty

Wildflower Mount Diablo Buck Lotus (Yellow) Scientific Name: Hosackia crassifolia Family: Fabaceae (Legume Family) Blooms: May-Jul Color: Yellow-Orange Perennial herb Native Jump to Blooming Now Blue / Purple Red / Pink White Yellow / Orange Invasive Plants

Orange Sulphur Colias eurytheme Pieridae Whites, Sulfurs Flies All year Host Plant Legumes, Vetches Nectar Plant Daniel Fitzgerald Female Underwing Daniel Fitzgerald Female Underwing Michael Marchiano Male Michael Marchiano White Female

Wildflower Mount Diablo Gamble Weed, Pacific Snakeroot, Pacific Sanicle Scientific Name: Sanicula crassicaulis Family: Apiaceae (Parsley-Carrot Family) Blooms: Feb - Apr Color: Yellow-Orange Perennial herb Native Jump to Blooming Now Blue / Purple Red / Pink White Yellow / Orange Invasive Plants Mike Woodring

Hoverflies by Jenn Roe Marvelous Animal Adaptations June 24, 2025 The oblique streaktail hoverfly, common on Mount Diablo, visits many types of flowers. Like all true flies, it has only two wings, while bees and wasps have four (two sets). If it looks like a bee and acts like a bee, is it a bee? Look closer, because that bee or wasp-like insect you see on the flower just might be a hoverfly, a fly in disguise. Hoverflies, also called flower flies, belong to a large insect family, Syrphidae, with over 200 species in California. Many species mimic the look of a bee or wasp to defend against predators that don’t want to eat creatures with stingers. But unlike bees and wasps, the hoverfly has no stinger and is harmless to predators and humans. Same as all true flies, it has two wings (one set) compared to bees and wasps that have four (two sets of wings). Also, notice the hoverfly’s big eyes are about the width of its abdomen, much bigger than a bee’s eyes relative to its bee body. Hoverflies are often seen hovering around flowers, hence their name. Many species feed mainly on nectar and pollen. They are important pollinators that provide this essential service while nectaring (sipping nectar). Hoverflies can be beneficial in another way, as pest control. The larvae (maggots) of some species eat aphids and other soft-bodied insects that gardeners and farmers consider pests. This is true for the oblique streaktail (Allograpta obliqua) pictured on this page. The female streaktail lays her eggs on plant parts near aphids. When eggs hatch, the fly larvae’s food is within easy reach. Download this article by Jenn Roe This drone hoverfly mimics its namesake, the drone (male) bee, in color and striping. However, the fly’s large eyes are about the width of its abdomen, a feature of flies but not bees. by Dan Sandri This fuzzy fly is a bumblebee mimic. Sometimes called a bumblebee plumehorn (‘plumehorn’ for its feathery antennae) the female lays her eggs in bumblebee or wasp nests. When the fly larvae hatch, they dine on nest debris and sometimes the host’s own larvae. Not very nice guests! BACK TO LIST

Wildflower Mount Diablo Yellow Woolly Paintbrush, Woolly Painted Cup Scientific Name: Castilleja foliolosa var. flava Family: Orobanchaceae (Broomrape Family) Blooms: Mar - Apr Color: Yellow-Orange Perennial herb Native Red form is more common. Jump to Blooming Now Blue / Purple Red / Pink White Yellow / Orange Invasive Plants Stephen Smith Ruth Ann Kishi

Blainville's Horned Lizard by Michael Marchiano October 1, 1998 The Coast or Blainville’s Horned Lizard (Phrynosoma blainvilli ) is considered to be an odd-looking creature by many people. Squat, flat bodied, and short-tailed with a wide head covered in spines, it causes one to consider the little lizard a miniature relic from the age of dinosaurs. In fact, its appearance gives rise to its nickname, “Horny Toad”. Growing to a length of five inches, this cryptic colored lizard depends far more on its appearance for survival than speed or agility. Its mottled coloration of large and small patches and bands on its body of various shades of brown, black, cream, and yellow allow it to blend into it environment almost to a point of invisibility. When threatened, it will first freeze and hope its camouflage will protect it. If attacked, it will run a short distance, stop suddenly, lay flat, and once again count on its coloration for protection. If grabbed, the horned lizard has a unique defense for repelling its attacker. It can actually squirt a quick stream of blood from the corner of its eyes with the hope of distracting or startling the predator and escaping. Another unique feature of this specialized lizard is its diet. Its primary food is native ants, such as species of harvester and carpenter ants. It does on occasion eat other arthropods such as beetles, crickets, and spiders, but 80-90 percent of its diet is indigenous ants. The introduction of Argentine ants (which have replaced native species) in areas once inhabited by Coast horned lizards has been one cause of their diminished numbers. These introduced ant species are not palatable to the lizard. Although three subspecies of this lizard inhabit California, from Baja up the Central Calley to the Sierra Buttes, the last vestige of these unique creatures in Contra Costa County is Mount Diablo. The overall population of the Coast horned lizard throughout California has been under threat because of habitat destruction, pesticides, agriculture, and the introduction of Argentine ants. Blainville’s horned lizards are generally seen in our coast range and the Central Valley from spring through fall, hibernating in burrows under ground in cold weather. Found in chaparral, mixed oak, and grey pine forest, sandy loam soil, and gravelly areas, these lizards need a mixture of open space and shrubbery with soil they can easily dig into as well as populations of native ants for food. They breed in spring, with the female laying a small clutch of eggs (average 8-12) in a burrow she excavates. Newborns hatch in late summer or early fall and are miniatures of their parents, about the size of a quarter. Once much more common in Contra Costa County, the population has decreased in recent years. On Mount Diablo keep your eyes open, especially on Eagle Peak, Twin Peaks, Black Point, White Canyon, Mount Olympia, and on the south side along Black Hawk Ridge. Because of its specialized diet and environmental conditions, this is a lizard that does not do well in captivity (horned lizards in North America can no longer be sold in the pet trade) so please enjoy them when you see them, but let them be. Enjoy this unique and marvelous creature along with the rest of the natural environment in Mount Diablo State Park. Blainville's Lizard changes color to blend with the soil. | Dan Sandri By Dan Sandri BACK TO LIST

Wildflower Mount Diablo Downy Navarretia Scientific Name: Navarretia pubescens Family: Polemoniaceae (Phlox Familiy) Blooms: May - Jun Color: Blue-Purple Annual herb Native Jump to Blooming Now Blue / Purple Red / Pink White Yellow / Orange Invasive Plants Kevin Hintsa

Wildflower Mount Diablo Alkali Mallow Scientific Name: Malvella leprosa Family: Malvaceae Blooms: Apr-Oct Color: White Perennial herb Native Jump to Blooming Now Blue / Purple Red / Pink White Yellow / Orange Invasive Plants