Birds of Mt. Diablo

 

 

 

 

Those are among the more than 200 species of birds identified by ornithologists on Mt. Diablo. According to the Mt. Diablo Interpretive Association, the park is a favorite place for birders for its superb examples of chaparral birds, spring migrants, numerous raptors, and such locally elusive species as Prairie Falcon, Hermit Warbler, Hammond's Flycatcher, Calliope Hummingbird, Sage Sparrow, and Black-chinned Sparrow.

 

The truly lucky may catch a glimpse of the spectacular but endangered California Condor, the largest bird in North America. Its wings may stretch nearly 10 feet from tip to tip. When in flight, the Condor glides on air currents to soar as high as 15,000 feet.

 

Condors were sacred birds to the Native Americans who lived here. These superb gliders travel widely to feed on carcasses of deer, pigs, cattle, sea lions, whales, and other animals. Pairs nest in caves high on cliff faces. The population fell to just 22 birds in the 1980s, but there are now about 275 free-flying birds in California, Utah, Arizona, and Baja California. 

 

Castle Rock Regional Park at the end of Oak Grove Road is a Peregrine Falcon nesting area. In recent years, the U.S. Forest Service and the East Bay Regional Park District have erected signs warning visitors to stay away when the peregrines are nesting. Those wishing to catch a glimpse of the majestic raptors must obey all park service signs. The Pine Creek area of the park is closed every year from February 1 to July 1 to protect nesting falcons. The park service says seven peregrines are now residents at the park. Peregrine Falcons are said to be the fastest animals on earth, capable of reaching speeds of over 200 mph.

 

Studies show that the breeding population of Golden Eagles in the northern Diablo Range is the largest on the planet; at least no other studies have published densities of territorial pairs higher than the researchers’ estimate of about 53 pairs per 1,000 square kilometers. Golden Eagle territories appeared to be occupied every year, which suggests a stable population. However, reproduction has suffered immensely in recent years, especially during the recent historically severe drought from 2014 to 2016. 

 

Local experts say the best time to go birding is from mid-April to early June, but there are birds here year-round. 

 

The best birding is normally in the canyons and the lower half of Mt. Diablo State Park, said Kevin Hintsa of the Mt. Diablo Interpretive Association. Probably the three finest areas of birding are Pine Canyon, Mitchell Canyon and the Rock City area, Hintsa said. The best examples of chaparral birds can be found in the area from just below Toyon Picnic area to Pioneer Horse Camp and also around Muir Picnic Area. The canyon areas such as Dan Cook Canyon and Curry Canyon can provide some shade in the heat of summer but avoid these two sites in winter, Hintsa said.

 

The area from Curry Point to Knobcone Point has the driest trail in rainy weather (and one of the hottest temperatures in summer). All of the canyons can be terribly muddy during the rainy season. Mitchell and White Canyon can be very exciting in April and May and is perhaps one of the least demanding of the trails. Donner Canyon can be equally exciting during this same time, but it is very rugged as are most of the areas around the peaks (such as Eagle and North Peaks).

 

The Summit area is generally very poor birding, although some good birds can be seen (mostly during spring migration) like Black-chinned Sparrow, Hermit Warbler (sometimes common), Calliope Hummingbird, Lawrence's Goldfinch (probably regular here in late spring) and once a Cassin's Finch. Blue Oak and Oak Knoll picnic areas can be superb in May, especially for warbler flocks.

 

For a short driving tour of the mountain in spring, start at South Gate Road and check the areas of Rock City, Curry Point area, Junction Campground area, Wildcat Group Camp, and Blue Oak-Oak Knoll picnic areas and, if time permits, a few pullouts along North Gate Road (especially for Lark Sparrow, Rufous-Crowned Sparrow, Rock Wren and Golden Eagle).

 

The preservation group Save Mt. Diablo put together a comprehensive guide to what and where birds can be seen in spring. The Mt. Diablo Audubon Society provides guided field trips for birders, and also has a gallery of Mt. Diablo birds.

 

iNaturalist, a project of the California Academy of Sciences and the National Geographic Society, assembled a checklist of Mt. Diablo birds that notes when the species was last observed.

 

A map of Mt. Diablo and the Diablo Range is available from Save Mt. Diablo. A field guide to Common Birds of Mt. Diablo by John C. Robinson is a good resource. 

 

Here's a look at some of our avian neighbors.