Saturday, April 13th I birded with Bruce Mast in Central Contra Costa. Though we only birded for part of the day, we still had a great time and found 111 species. We started owling in the San Pablo Reservoir area. It was pretty quiet, but we managed to hear a Great Horned (and saw one as well), a Northern Saw-whet, and a Barn Owl. Additionally, we heard both Sora and Virginia Rails.
In the Mount Diablo area, we heard many Great Horned and Western Screech-Owls, along with a few Common Poorwills. In the morning, we headed off to Mitchell Canyon. At White Canyon, we found a good amount of diversity. Among the California Thrashers, Blue-gray Gnatcatchers, and other expectable chaparral species, we had a good flight of hummingbirds and healthy numbers of migrants. It seemed like everywhere we went, we could hear the odd display call of the Calliope Hummingbird. We got good views of several of them, and estimated there were probably around 10 in the area. Additionally, we found a few Rufous Hummingbirds, along with Yellow-rumped, Orange-crowned, Nashville, Black-throated Gray, and Wilson's Warblers, Black-headed Grosbeak, Hermit Thrush, Ruby-crowned Kinglet, and Fox Sparrow. We then headed back to the main trail and headed up a little farther. Here, along with Black-headed Grosbeak and a Hutton's Vireo, Bruce spotted a singing early male Lazuli Bunting. While walking back to the parking lot, we stumbled upon a group of three calling Hammond's Flycatchers. Along the creek, there were a couple Pacific-slope Flycatchers singing. A little farther down, we found another Hammond's Flycatcher and a Warbling Vireo. We then got back to our car, and headed off to Black Diamond Mines.
In my three experiences of birding this site, I have found that Somersville road, the road leading up to the mines, is often just as good or better than the mines themselves. This proved no different this time, and we were pretty successful on the roadside. At the first pullout, we found a Bullock's Oriole, a Wild Turkey, and a couple American Goldfinches (there were also hordes of Lesser Goldfinches along this road). Our next pullout was our most successful one. At this spot, the canyon narrows, so the chaparral comes closer to the road. Here, we found several Western Kingbirds. In the chaparral, we heard a Rufous-crowned Sparrow and, after a little while, a Rock Wren. Then Bruce found the Rock Wren, and we were both able to enjoy good scope views of the bird. We then continued along the road, but stayed alert. All of the sudden, I saw a bird that looked very much like a Lark Sparrow pop fly some nearby grass. We waited for a while, then the bird flew and landed in an oak. It offered great views, confirming its identity, and we were both satisfied.
We then arrived at the mines. For time's sake, we decided to just bird around the parking lot. At the parking lot, we found several Tree Swallows and an Ash-throated Flycatcher. We took a small trail from the parking lot and followed it about 100 yards. Then, we ran into a small foraging flock. Among some Juncos and Yellow-rumped Warblers we found a Cassin's Vireo and a Ruby-crowned Kinglet. Then, we saw the continuing male Phainopepla fly by and land on an adjacent oak. As we walked back to the car, we noticed a Northern Harrier coursing over a nearby ridge.
We pulled out again when we were coming back on Somersville Road. This time we saw another Ash-throated Flycatcher, another male Northern Harrier, and another Bullock's Oriole. While listening and looking, we heard and then saw a male Belted Kingfisher fly right overhead. We also saw another Lark Sparrow and an Orange-crowned Warbler.
Our next stop was looking for the Greater Roadrunner at the Deer Ridge Golf course in Brentwood. After looking for the location for a while, we eventually found the reported spot and started searching. We searched all around the vicinity for a while and came out empty-handed. However, we noticed at least 20 Say's Phoebes in the area, a curiously high county on this date. I suppose they were mostly migrants, though a pair was copulating, so perhaps some will nest in the area. We then decided to wander up the hillside that the Roadrunner had been seen on. While walking along the hillside, an adult Swainson's Hawk flew overhead. After walking for a quarter of a mile through the tall grass, we heard the distinctive cooing of the roadrunner. A little ways farther along the trail, and we were able to hear it quite clearly. Unfortunately, though, after 30 more minutes of searching, we failed to lay eyes on the bird. We then made a brief stop by the Golf Course ponds. They were quite productive, and we were quickly rewarded with Common Gallinules including one on a nest, Canada Goose, Mallard, Gadwall, Black-necked Stilt, Greater Yellowlegs, Long-billed Dowitcher, and Great-tailed Grackle. We then headed off to Mallard Reservoir for an update on the ducks.
On the reservoir, we couldn't locate the Lesser Scaup I'd found last week. However, the Eared Grebes and Bufflehead continued, along with a Ruddy Duck and some Cedar Waxwings. We then went to Waterbird Park to see what was happening there. In our brief stop, we managed to find most of the expected ducks, including Cinnamon Teal, Northern Shoveler, Northern Pintail, etc. along with Marsh Wren and Great-tailed Grackle.
Logan Kahle (and Bruce Mast from Oakland)