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Pollen Wasp by Dan Sandri A much friendlier wasp June 20, 2025 by Dan Sandri These days there is a wasp flying around Mount Diablo State Park’s Bunchleaf Penstemon (Penstemon heterophyllus ) that looks somewhat like a Western Yellowjacket (Vespula pensylvanica ), but is much more peace-loving and delightful! It is a Pollen Wasp: Pseudomasaris vespoides . It isn’t a pest or a predator - this Pollen Wasp behaves more like a bee. Pseudomasaris vespoides is a specialist that relies solely on Penstemon for pollen and nectar to feed its larvae. To find it, look for the Penstemon . These wasps differ from yellowjackets in that they are larger and have clubbed antennae, among other differences. Unlike most bees, they do not carry nectar and pollen on their legs. They carry pollen and nectar back to their mud nests using their crops. Like most native bees, each female wasp is a solitary nester, not a communal nester – each nest cell contains one egg and the nectar and pollen to feed the larva when the egg hatches. A mud nest may be a collection of parallel cells attached to a rock. Certain Penstemon plants, including some endangered plants across the Western United States, rely on Pseudomasaris vespoides for pollination – they would go extinct without the wasp. Pollen wasps have long tongues that enable them to reach the nectar at the base of long, tubular flowers. If you watch Pseudomasaris vespoides wasps collect nectar from Bunchleaf Penstemon, you will hear them too, as their back make a rasping sound as they rub against spines in the Bunchleaf Penstemon flowers. Note that there are at least three species on Pseudomasaris in Mount Diablo State Park, but if you see one on Bunchleaf Penstemon, it will be Pseudomasaris vespoides . The upper parts of Mount Diablo have a lot of Penstemon right now, and a lot of these wasps. Perhaps try Mary Bowerman Fire Interpretive Trail or one of the other higher elevation trails. by Dan Sandri Pollen Wasp (Pseudomasaris vespoides) by Dan Sandri Pollen Wasp (Pseudomasaris vespoides) BACK TO LIST

Wildlife Photography Guidelines by Melissa Groo, used with permission Taken from National Geographic 7/31/19 article, "How to Photograph Wildlife Ethically" July 31, 2019 Gray Fox, by Dan Sandri “The ethics of photography are the same as the ethics of life, and they all revolve around respect.” As you strive to capture images of wildlife in Mount Diablo Sate Park, please pledge to have as minimal an impact as possible when photographing flora and fauna, by following the guidelines below. Remember, the use of drones is prohibited at all times. • Do No Harm – I will not destroy or alter habitat for a better shot, will always let animals go about their business, especially in breeding season, and will strive to understand signs of stress. • Keep It Wild – I will never feed our wild friends, in hopes of a photograph, or otherwise, avoiding the possibility of having them connect human contact with food. • Follow the Law – I will always obey applicable laws as I photograph. • Consider the Captive – If photographing wild animals in captivity, I will first ensure the facility is both legal and ethical. • Caption with Honesty – I will always be honest and transparent about the backstory of a pic – camera trap, captive critter, etc. – so as not to deceive viewers. I will also protect sensitive species or habitats by not disclosing location. For more information visit https://www.nationalgeographic.com/animals/article/ethical-wildlife-photography (requires free subscription to view) California Pocket Mouse (Chaetodipus californicus) by Dan Fitzgerald.jpg red-tailed hawk by Dan Sandri.jpg Ground Squirrel.jpg Tarantula by Ken Lavin.jpg Peregrine by Scott Hein.jpg BACK TO LIST

Springtime on the North Peak Trail by Frank Valle-Riestra Reproduced from Mountain News, Spring/Summer 2011 May 1, 2011 Five Peaks; View of Summit • Paul Salemme Of the many attractions of Mount Diablo, perhaps the most eagerly anticipated is the annual return of the mountain’s spectacular wildflower display. There are those trails along which a particular species predominates— globe lilies along the Globe Lily and Perkins trails. Johnny-jump-ups along the Coulter Pine and Bruce Lee Spring trails. California poppies on the slopes of Long Ridge. Bird’s eye gilias on the Bald Ridge trail. But there is one trail that has just about all of them, growing together in astounding profusion: the North Peak Trail, passing through the sun-drenched meadows just below the summit, the park’s Elysian Fields. If you have never been there at the time of blooming, you owe it to yourself to go. Start your exploration at the lower summit parking lot; here you will find restrooms, water, picnic tables—and incomparable views, another attractive feature of this hike. As you leave your vehicle, you will be drawn to the unobstructed panorama to the east; a broad, sweeping vista of apparent wilderness stretching from the Central Valley, across to the distant Mount Hamilton, and out toward Mount Umunhum in the Santa Cruz Mountains. It is a beautiful and impressive sight in all kinds of weather. (1) Now look for your trailhead, the beginning of a steadily descending section of the Summit trail, easily spotted near the vehicle entrance to the parking lot. This wide, well-maintained trail passes through a forest of mature buckbrush and bay trees, with occasional openings to reveal the ever-shifting views. Here you do have a dominant flowering species—the trailside buckbrush itself, a wild lilac, which bears clusters of white flowers in abundance. On warm, sunny days, the air is filled with their heady, sweet perfume. Look out also for trailside stands of yerba santa, with profuse trumpet-shaped white blooms, slightly tinged with purple. The plant, named “Sacred Herb” by early Spanish settlers, was used by Bay Miwoks as a remedy for respiratory problems. (2) The trail section ends at Devil’s Elbow, the sharpest Summit Road curve; a trail sign points out the beginning of the North Peak trail, heading toward Prospectors Gap. Here you must stop to admire the extraordinary assembly of Franciscan chert cliffs, pinnacles, and rocks spilling down from the summit, crowned by towering Devils Pulpit to the north. Particularly when highlighted by rays of the sun, these splendid 140-million-year-old formations, the color of congealed blood, constitute one of the most amazing Bay Area natural sights. Turn left (east) onto the North Peak trail; it begins with a short but very steep section, which requires careful attention to your footing. At first the flowers are not as profuse as promised, but you will spot examples of blue witch, wallflower, and naked buckwheat, among others. There are some fine specimens of juniper along the way, loaded with berry clusters thick as grapes. The farther you go, the more colorful becomes the massed wildflower display, with the climax growth just below Devils Pulpit (3), at the point where the trail veers leftward toward the north. Here, in meadows sprinkled with picturesque boulders, perhaps two dozen species form a broad carpet of happy cohabitation. Take a moment to rest on a boulder, to admire the scene around you and the now visible distant Sierra Nevada, stretching across the length of California. But more pleasures await you as you proceed along the intimate single-track trail, perched above the steep canyons far below. Even though the area has not been fire-ravaged since 1977, the fire-induced wind poppy may still be found occasionally—a rare find, indeed. On the other hand, the sloping meadows farther along toward Prospectors Gap abound with broad swaths of goldfields, a joy to the eye. The only thing to mar your pleasure is the evidence of pig damage, from animals descended from pigs released by early ranchers for hunting purposes. They are a problem all over the mountain, bulldozing the moist earth to dig up wildflower bulbs. (4) Just before Prospectors Gap, the trail begins a long, steep descent with rather treacherous footing. Unless you wish to reach the gap for some reason, stop before attempting the descent and note a little unmarked path on your left. A few steps take you to a spot that opens up new vistas to the west, as well as great views of the Ransom Point monolith above, and Summit Visitor Center—our own modest mountain-top castle. The total round-trip hike to this end point and back is about 2¼ miles, and your climb is 620 feet, mostly on the way back. Allow 2½ hours. Of course, you can extend your hike past Prospectors Gap to include the length of the incomparable Bald Ridge trail, with its wonderful carpets of bird’s eye gilia. Be aware that this will increase your hike by another 3 miles, with an additional climb of 650 feet, allow two more hours. And say hello to the melodious California thrashers, which favor that particular environment. A word of caution; it is impossible to foretell the best time for the wildflower display—it usually occurs between March and May—or whether the display will be a decent one. But the North Peak trail offers ample rewards even if flowers happen to be skimpy. Check out more Spring Wildflower Hikes: Globe Lily Trail Black Point Trail Mary Bowerman Hike North Peak Trail Map BACK TO LIST

Red-tailed Hawk by Dan Sandri January 1, 2024 Dan Sandri Keep an eye out and an ear open! The Red-tailed Hawk (Buteo jamaicensis) is probably the most common hawk across the country, and is often seen above and around Mount Diablo State Park. Our Red-tailed Hawks are most numerous across California in Winter, when many hawks return from northern lands. These are large, broad-winged hawks that usually (but not always!) exhibit an orange-red tail. Along with the tail, the best indicator that the hawk you are looking at is a Red-tailed Hawk is a brown-streaked “belly-band” (sometimes dark, sometimes more finely-streaked) across the tummy, and dark patagial lines on the front edge of the underside of the wing when seen from below. See the photos for examples of the belly band and patagial lines. Identification can get tricky if the bird is dark Harlan’s subspecies or a dark-morph adult or juvenile. Their preferred food is mammals, such as voles, gophers, ground squirrels, rabbits and the like, but they will also eat lizards, snakes, birds and other animals. Because they have hollow bones, these large hawks are quite light in weight - an adult female might weigh in at only 3 pounds. Their classic, recorded scream can be heard in many a Western movie, even when the bird shown is an eagle or a kite! Bird Guide: https://www.mdia.org/birds-1-1/red-tailed-hawk red-tailed hawk1 DSandri.jpg red-tailed hawk2 DSandri.jpg BACK TO LIST

Weird and Wonderful: Button's Banana Slug by Dan Sandri June 1, 2024 Dan Sandri Did you know, as you hike or bike Mount Diablo in the rainy season, you may encounter a truly strange and imperiled mollusk underfoot? They are not at all common, but we recently found one on our monthly MDIA BioBlitz hike on Mitchell Canyon Road. The Button’s Banana Slug (Ariolimax buttoni), the banana slug found on and around Mount Diablo, has a status of Globally Imperiled, meaning it is at high risk of extinction or collapse due to restricted range, few populations or occurrences, steep declines, severe threats, or other factors. The Button’s Banana Slug is a fascinating creature! The species has a yellowish-tan hue and can be either spotted or unspotted. It is a detritivore that eats dead organic matter, but also eat plants (they are herbivores), as well as animal feces and mushrooms. Its mouth is on the bottom of its head with a tongue called a radula that is covered in microscopic teeth to help break down food. Get this: the slug excretes waste through the anus located on the side of its head! Banana slugs are simultaneous hermaphrodites—meaning it has male and female sexual organs at the same time. However, sexually mature individuals can have no male reproductive organs, reduced male reproductive organs, or normal male reproductive organs. Those with normal male reproductive organs can mate either as a male or a female, or can perform both roles at the same time if mating as a pair. Or it can self-fertilize. Speaking of truly strange: during reproduction, Ariolimax buttoni may engage in apophallation (no details here - you can look that word up if you like strange and can stomach it!). When looking for food or a mate, Ariolimax buttoni moves via a foot on its underside that contracts and relaxes. It can glide over surfaces by producing a slime layer that aids in combating friction. The slime it produces deters predators because it is toxic and causes numbing to the mouth of organisms that attempt to ingest it. So, next time you see a Button’s Banana Slug, you will be looking at a rare, exceptional slug! -Dan Sandri BACK TO LIST

Ruby-crowned Kinglet by Dan Sandri January 1, 2024 Dan Sandri Hey! What’s that small, seemingly-restless bird, on the move through the tree branches, making rapid chipping sounds and flicking its wings? It’s there… but then it isn’t… It may be one of our most active Mount Diablo Winter residents: a Ruby-crowned Kinglet (Corthylio calendula). A Ruby-crowned Kinglet is an olive-green and golden-colored bird, with a prominent white eye ring, white wingbar and very small, thin bill. This wingbar contrasts with a black bar on the wing, which helps differentiate it from the similar-looking, but a bit larger, Hutton’s Vireo (Hutton’s Vireos also have a more-conical bill). The “ruby crown” possesed by the male is only occasionally visible, when the bird is agitated or excited, especially in Spring. In Summer, Ruby-Crowned Kinglets have migrated to the north or northeast and are common in conifer and mixed forests in the northwestern United States and across Canada. Ruby-Crowned Kinglets nest high in trees, and therefore in this season prefer taller, older trees. During migration and in Winter, they are common in woods and thickets across most of the continent. Ruby-Crowned Kinglets prey on spiders and many types of insects, foraging in tree foliage, flitting about, hovering and pecking in in their search for food. These birds also eat a small amount of seeds and fruit, including poison-oak berries. So keep an eye out for this Kinglet – or an ear for their chatter, as they are often heard first. Tis the season! Bird Guide: https://www.mdia.org/birds-1-1/ruby-crowned-kinglet Ruby-crowned Kinglet (Corthylio calendula)1 Dan Sandri.jpeg BACK TO LIST

What's Blooming Now on Mount Diablo See the list of blooming plants BACK TO LIST

Coyote By Jenn Roe and Dirk Muehlner Marvelous Animal Adaptations May 21, 2025 by Dirk Muehlner The coyote is a very vocal mammal that communicates with yips, whines, woofs, huffs, growls, and group yip-howls (part of a complex greeting ceremony). It’s best known for its iconic lone howl, which announces a solitary coyote separated from its pack. Early Aztec Indians called it “coyotl”, which means barking dog, and scientists label the coyote: Canis latrans, which also translates into barking dog. Its different vocalizations serve as alarms, greetings, or search for contact. Where do coyotes live? In the past, coyotes were most numerous in grasslands, but after humans exterminated their main predator, the highly territorial gray wolf, coyotes vastly expanded their range throughout North America and parts of Central America. The versatile (dare we say “wily”) coyote can now be found in almost all habitats and even some cities and suburbs. Its preferred den is a burrow in a slope, but a hollow tree trunk, dense brush pile, or even an abandoned car can be home. It’s Hard to Starve a Coyote The coyote’s ability to survive and thrive is further supported by its flexible menu. Mostly carnivorous, it prefers small prey such as rabbits, ground squirrels and other rodents. It will also consume birds, eggs, fruits and even cats and dogs. Coyotes in neighborhoods are attracted to pet food, garbage, and even bird feeding stations. Download this article by Dirk Muehlner Coyotes typically hunt alone, but sometimes in pairs and family packs. When giving chase, or running from danger, the coyote’s top speed can reach up to 30 mph, making it the swiftest canine in North America. BACK TO LIST

Bob's Pond Hike by Frank Valle-Riestra Reprinted from Mountain News, Spring/Summer 2013 Frank's Favorite Hikes May 1, 2013 In 1998, the Save Mount Diablo organization completed purchase of the Silva cattle ranch land, some 430 acres of beautiful, hilly landscape in the upper reaches of Riggs Canyon. Five years later, the acquisition was incorporated into the Mount Diablo State Park. It remains today a sparsely visited corner of the park in its eastern extremities, a hidden treasure well worth exploring. The centerpiece of this extraordinary landscape is Bob’s Pond, a man-made stock pond cradled in a hollow on the flanks of Windy Point. It is named after Bob Adams, an erstwhile director of Save Mount Diablo and a guiding presence during the procedures to acquire the land. (For more detail, see Rich McDrew’s book, Mountain Lore, available in our Visitor Centers.) The lovely green pond, with its ring of magnificent sycamore trees, stands like an emerald jewel among the undulating meadowy hills, a welcome focus to the area’s wildlife. Tassajara Creek Trail forms a grand loop encompassing the pond. It was built at the time of the land acquisition by the East Bay Trail Dogs, a group of volunteer trail enthusiasts. This well-laid-out and engineered trail lies in pretty remote country, and it takes some effort to get to it. It is most readily reached from two park trailheads. One is located at the end of the paved Finley Road, which runs north from Camino Tassajara east of the Blackhawk development in Danville. The other trailhead is at Red Corral, my own preference. Red Corral is reached from the town of Clayton by following Marsh Creek Road to its junction with Morgan Territory Road. Turn right onto Morgan Territory Road and continue on it for 4.2 miles to reach twin one-lane bridges. Red Corral is 0.5 miles beyond, and you will spot it on your left, still red after all those years. There is very limited parking at the trailhead on the right edge of the road; be sure not to block off the entrance gate to inholdings. Before you start your hike, take a quick look at a stone memorial to Jeremiah Morgan, first settler in this area (1857), placed there by the Save Mount Diablo organization. It is located behind a locked gate in the Red Corral (to discourage vandals); the inscription on the memorial is reproduced in the Mountain Lore book. After passing through the well-marked park gate, continue straight ahead and upward on Morgan Creek Road. The steadily rising road parallels Jeremiah Creek, in a dense deciduous forest, which brings welcome coolness during the hot summer and fall months. It is part of a pattern you will experience during your hike: tree-less high meadows in full sun, interspersed with picturesque, gentle oak groves and deep, dark forested canyons. At a sharp bend of the steeply rising road, look for a post to your right announcing the start of Jeremiah Creek Trail. The trail is just a delight: a narrow, single-track path meandering through an unspoiled by Frank Valle-Riestra Reprinted from Mountain News, Spring/Summer 2013 Frank’s Favorite Hikes bob’s pond hike wilderness, rising gently up to the crest of Highland Ridge. It is here, in the midst of an oak savannah and along the banks of Jeremiah Creek with its pools and ponds, that you may experience that peace of mind engendered by a truly remote corner of nature. When you reach the crest at Old Finley Road, stop for a moment to take in the magnificent view of Riggs Canyon far below you, a panorama that expands to include many distant Bay Area highlands as you ascend Highland Ridge Road to your right. The road climbs toward the park boundary and is quite steep at times, but you will find some welcome rest stops on mossy rocks under venerable old oaks. Be on the lookout on your left for a post marking the beginning of the Tassajara Creek Trail. At first the trail follows an old farm road but soon veers off as another intimate single-track path. After all of the climbing you have done, it is a pleasure to march along this gentle path as it follows contours in its descent toward the headwaters of Tassajara Creek. Here you are mostly in the midst of meadows. The tall grasses do not favor great wildflower displays, but California Poppies manage to push through during a good part of the year, golden explosions to gladden the eye. Eventually, Bob’s Pond comes into view, in a hollow below the trail; the path then slowly circles around to an overlook marked by, of all things, a nice picnic table. It is not something one might expect in this remote location—clearly a labor of love to drag it all this way. It is a good place for a little picnic, to sit and rest and admire the panorama. A short way beyond, the trail plunges into the depths of the canyon carved out by Tassajara Creek, a silent, mysterious world of a dense riparian forest. The trail builders did a fine job of negotiating the complex stream topology. You will delight in the ever-changing scenery and the cool air—and the forest flowers, particularly in spring: Giant Trillium and Checker Lilies bloom in profusion. At its end, the trail breaks out again into open country and rises steeply to meet Old Finley Road. A left on the road brings you back to the junction with Jeremiah Creek Trail after another short climb. Retrace your steps along Jeremiah Creek Trail and Morgan Creek Road to Red Corral—mostly down-hill!—to complete one of the park’s great hikes. A word of caution: On the Jeremiah Creek Trail in particular, there are luxuriant stands of poison oak at trail side, but these are easily avoided with some care. Long stretches of Tassajara Creek Trail in the upper meadows have been badly churned up in wet weather by horses, stray cows, and wild boars. The total distance covered is about 5.5 miles; expect to climb some 1,870 feet and to spend four to five hours, with a few rest stops. BACK TO LIST

Mary Bowerman Trail by J. Frank Valle-Riestra Reproduced from Mountain News Spring/Summer 2014 May 1, 2014 Mike Woodring In 2024 we celebrated the 50th anniversary of the founding of the Mount Diablo Interpretive Association. One of the first major projects undertaken by the infant association was a survey of the park’s trails network. Small groups of dedicated hiker-environmentalists spread out over the far reaches of the park as it was in the mid-’70s, assessing the existing trails and recommending new trails. One recommendation was construction of what is now known as the Mary Bowerman Trail. The summit of the main peak was a primary destination of the visiting public, but no trails were there for visitors to experience close contact with the mountain’s exceptional natural environment. The first step was to lay out a possible route. Surveys of the topography revealed that a logical circuit of the summit region could be visualized with no anticipated damage to plant life and geological formations. The circuit was to be fairly level, along a contour line, with an overall distance of about a mile. Full of enthusiasm, our little band of interpreters marked the route with wooden stakes with red ribbons. We came back a few days later to find almost all of the stakes gone! So back we went and repeated our layout. A couple of days later, the same thing! And then it dawned on us. This was not the work of vandals, it was the work of animals (raccoons? skunks?) resenting this intrusion into their homeland. This was one of many delays; some, as expected, came as a result of environmental reviews by the Department of Parks and Recreation in Sacramento. Finally, with preliminary approval, Park Ranger Dick VanEtta single-handedly constructed a primitive path along the proposed circuit, in just a few days. But all in vain. For it was August of 1977, and soon after VanEtta’s efforts, lightning struck on Twin Peaks, and the resulting fire roared upward toward the summit. The summit buildings were saved, but the fire destroyed the plants on the north-facing slopes below, as well as vestiges of the new trail. The Bay Area was stunned by the damage to the park, and money poured in to help regeneration, along with suggestions which simply proved that many kind-hearted people did not understand that post-fire regeneration was best left to nature. Proposals such as aerial scattering of grass seeds, planting of redwood groves, even introducing palm trees were mercifully rejected. But the money was put to good use. The decision was made to build the trail as originally envisioned, through the burnt area, and to dedicate the trail to fire interpretation. After almost five years of planning, a spectacular trail, The Fire Interpretive Trail, was completed in 1982 by a wonderful group of young people from the California Conservation Corps, under the direction of Carlos Espinoza, a dynamo in a wheelchair. A grand trail dedication was held at the trailhead, with lots of visiting celebrities, fluttering flags, and politicians. William Penn Mott Jr., then superintendent of California State Parks, spoke, as did Senator John Nejedly and Mary Leo Bowerman, celebrated botanizer of Mount Diablo. Dr. Bowerman was a founding member of MDIA and co-founder of Save Mount Diablo, our sister organization. Dr. Bowerman passed away in 2005 at the age of 97; The Fire Interpretive Trail was renamed in her honor. Following extensive incineration during the recent Morgan Fire, the trail continues to serve as a fire interpretive trail, to allow the public to monitor post-fire recovery of the plant communities over the coming years. Ironically, Dr. Bowerman did not originally favor a trail through the area. She was afraid, with some justification, that the construction effort and large visitor volume would impact the fragile plant life. Fortunately, rare and sensitive plants such as Bitterroot (Lewisia Redidiva) have fared well. The trail has been developed as a nature trail, and numbered posts refer to some highlights listed in a brochure available in a box at the trailhead. The 0.7-mile loop is no great challenge to the dedicated hiker, but with the help of the trail brochure, it offers an unusual range of discoveries. There is actually much more to see than the described features at the numbered posts, and close observation rewards you with some surprises. For instance, upon reaching the wooden platform called “The Bridge”, you might notice in the lower right corner a textbook example of a geological nonconformity. This is a phenomenon of two different rock types (in this case, shale and greenstone) being joined together along a seam. This kind of sudden change implies that the two rock types, formed separately perhaps millions of years apart, were squeezed and rubbed together by displacement forces, such as the upward thrust of the mountain’s piercement structure. On the trail’s southern rocky section, look for evidence of “slickensides”, highly polished surfaces formed by friction between rock masses moving relative to one another. During the spring months, be on the lookout for some unusual wildflowers. Just beyond The Bridge, at the point where the trail turns sharply toward the east, you pass a cherty scree slope on your right. Close inspection of the loose rocks will reveal the presence of small plants struggling to come to the surface, in the shape of small green spiders about the size of a tarantula. These are examples of Bitterroot, and if you are lucky, you will be there to welcome the spectacular white blooms. Other flowers worthy of attention: Brewer’s Rock Cress, seemingly growing out of the rock, in greenstone crevices in the cliff behind The Bridge. Astounding fields of pink Claytonia smothering an expanse of broken chert just before you reach the short side trail to Devil’s Pulpit. The side trail is often graced in June with Mariposa Lilies, and miniature Penstemon fight to survive at the base of the Devil’s Pulpit monolith, a favorite climbing rock. Ah, there are so many wonderful things to see on this trail, which, along with MDIA, has now been with us some fifty years. After parking your car at the lower summit parking lot, walk up a few steps to the trailhead, at the bottom of the steep one-way road leading to the summit. A clockwise circuit is recommended; you will finish your hike just across the road from the trailhead. Enjoy and celebrate! Mary Bowerman Interpretive Trail Guide Check out more Spring Wildflower Hikes: Globe Lily Trail Springtime in North Peak Black Point Trail Mary Bowerman Trail Map by Kevin Hintsa Mary Bowerman Trail Fire Recovery BACK TO LIST

Clark's Sphinx Moth by Dan Sandri Who thought a moth could look so cool! March 20, 2025 Dan Sandri Try to focus on that green blur in front of a blossom, perhaps a Blue Dicks flower (Dichelostemma capitatum ) or vetch (Genus Vicia ). Is it a hummingbird? Perhaps. But it may be a Clark’s Sphinx moth too! This time of the year (from March to June), they are flying about the oak woodland and surrounding grasslands from flower to flower, drinking flower nectar from a variety of flowers. It moves so quickly to another flower, uncurling its long proboscis to reach into flowers. They are not abundant, but I see them nearly every year. Clark’s Sphinx moths have a greenish forewing and an orange hindwing that has a black band along its base. Clark’s Sphinx range from Baja California north to British Columbia, and east to Idaho, Wyoming and Utah, and can be found in Oak woodland foothills. They lay eggs on Elegant Clarkia (Clarkia unguiculata ), the sole host plant that their caterpillars feed on. The eggs hatch in about 10 days, and once fully grown, the caterpillars pupate in burrows dug under rocks or other objects. They overwinter there and emerge the following Spring. I hope you see one! Clark's Sphinx Moth BACK TO LIST

Mount Diablo Western Toad by Joyce Gross A Preliminary Survey April 1, 1998 By Chris Brown, US Geological Survey, Western Ecological Research Center - San Diego Field Station [Public domain], via Wikimedia Commons In April 1998 I photographed Bufo boreas (western toads) breeding and laying eggs in Little Pine Creek. Of the approximately 20 toads present, females predominated. My previous experience observing amphibian breeding congregations indicated that this was unusual--normally there are more males than females--but I didn't realize how unusual until Bruce Waldman, a herpetologist at the University of Canterbury, New Zealand, saw my photos. Bruce also pointed out that many of the eggs I had photographed were irregularly shaped and not viable, probably "old" eggs, ovulated a week or more prior to actual oviposition. Bruce and I monitored Little Pine Creek in the spring of 1999. Toads always return to the same locations to breed. However, we saw no evidence of reproductive behavior. We found no toads, no eggs, and no tadpoles. Amphibian population declines have been occurring with alarming frequency all over the world during the past few years. There are many possible causes, including pathogenic organisms (e.g. chytrid fungi), high UV-B radiation, exotic predators, and habitat destruction. One of the least understood possible causes is pollution by pesticides, herbicides, and residues of commercial plastics. These compounds are similar in chemical structure to estrogen and other reproductive hormones. Thus it is feared that even at very low concentrations, which may pose no toxicological risk to organisms, these chemicals may mimic female hormones and disrupt normal endocrinological processes. The result might be altered reproductive timing that could contribute to reproductive failure. Of course in this case the reasons for our observations may be completely unrelated to the causes about which we are speculating. In 2000, we received a permit from the park to study the toads and test a few if we found evidence of reproductive abnormalities. I visited the park twice a week from February through June. I found normal breeding activity, resulting in small toadlets by June, in two locations in the park: two miles away at the pond off the Bruce Lee trail in Mitchell Canyon, and two miles in the other direction in a cattle pond near China Wall. At Little Pine Creek there was once again no evidence of reproductive behavior. I found two juvenile toads, but no adult toads in or near the creek, and no eggs and no tadpoles. What happened to the adult toads in the vicinity of Little Pine Creek in Mt Diablo State Park remains a mystery. http://amphibiaweb.org BACK TO LIST