San Diego Natural History Museum--Your Nature Connection[San Diego County Bird Atlas Project]

Bird Atlas News and Updates
Winter 1999

Bird Art on the Internet
Planning Ahead as the Atlas Passes Its Halfway Point
Prepare to Clear the Winter Threshold in Your Square!
Christmas Bird Counts
Blockbuster Weekends
WingDing Things

Bird Art on the Internet

Next time you're surfing the Internet, check out (note the lack of "www"). Cornell University is offering a virtual tour of "Beautiful Birds," an exhibit of rare antique bird books from the Hill Ornithology Collection. The site traces the evolution of the printing of bird illustration from the 18th to the 20th centuries, as the techniques of wood and metal engraving and chromolithography developed. And it traces the artistic evolution of bird illustration from pioneers like Mark Catesby and Alexander Wilson through John James Audubon to John Gould and his contemporaries.

The site features some of the most exquisite paintings in the history of bird art. It allows you to view them at a variety of magnifications—let your computer take its time to read in the fine detail of the craftsmanship. You can follow the curator's tour or wander as you like among the many images. The site is an outstanding example of making available to the public historic works whose irreplaceable originals must inevitably be carefully guarded and conserved.

Kenneth and Dorothy Hill donated the rare books to the Cornell library, along with the endowment sustaining the collection and the means for making it accessible via the Internet. They are also major patrons of the San Diego Natural History Museum, of habitat conservation in California, and of ornithology in San Diego--I am honored to be able to acknowledge Ken as the key donor making the publication of my earlier Birds of San Diego County possible in 1984. I thank him for sending me to Cornell University for the American Ornithologists' Union meeting in August, enabling me not only to see the exhibit of rare books for myself, but to present to the worldwide scientific community the research Karen Messer and I recently completed on identification of the Alder and Willow Flycatchers.

--Philip Unitt

Planning Ahead as the Atlas Passes Its Halfway Point

Ann and I have taken advantage of the "down time" between the breeding and winter seasons to strategize how we can maximize our coverage in the two and a half years of data gathering we have remaining for the bird atlas. A tool we have developed for helping with this is a spreadsheet of the squares that have not been adopted or are still lagging. It has the breeding and winter target lists for each square and the percentage of the target list confirmed breeding, possibly breeding, and recorded in winter in them. There are also comments about the existing data, ownership, access points and contacts, and other information that might help us cover the square. The spreadsheet helps us plan for blockbuster weekends and deploy the field assistants made possible by our grants where the need is greatest. We are eager to pass the information on to any interested participant. We hope that some of you may be inspired to adopt some of these squares or make some incidental observations in them. Because the spreadsheet runs 23 pages on legal-sized paper we prefer to send it in electronic form, in Excel as an e-mail attachment or on a diskette. If you would like a copy, please tell us which medium you can handle.

Now that the number of poorly covered squares is dwindling, with the aid of the spreadsheet, we can focus on them more clearly. So I am highlighting some squares that need further work in the hope of attracting attention to them.

Square D12, Wilderness Gardens, covers only part of the park, but this includes the part from Highway 76 down to the headquarters buildings. It thus includes some nice riparian woodland and a bluff suitable for nesting kingfishers though not the ponds. The rest of the square is mostly orchards and the steep south-facing slope of Palomar Mountain, but these are cut by Marion, Agua Tibia, and Frey creeks, and the habitat map shows quite a diversity of sage scrub, chaparral, and woodland habitats. Recent maps show a Gomez Truck Trail winding up the slope through the patch of grassland noted in the article on the Grasshopper Sparrow. So far we have only 2 hours worth of data on D12 for the breeding season and none at all for winter.

Square G20, Upper Warner Valley, sits on the intersection of highways S-2 and S-22, between Lake Henshaw and Ranchita. It lies almost entirely within the empire of the Vista Irrigation District, largely inaccessible to the public. This square, however, offers a notable exception: the Pacific Crest Trail. The trail crosses the entire length of the square from north to south. Grassland, chaparral, and oak woodland are also visible along Highway S-22, which crosses the square from west to east. We have some breeding data for G20 after Lori Hargrove covered it one (windy) day last spring. The winter data are still poor (only 47% of target) despite the square's being within the Lake Henshaw Christmas Bird Count circle.

Square K16, Hatfield Creek, lies just northeast of Ramona along Highway 78. There are also several back roads giving access to varied habitats, including riparian woodland and grassland. An interesting feature is the pond just south of the eastern intersection of Highway 78 and Rancho Santa Teresa Drive, easily scoped from the latter. We have surprisingly good data for this square but they are based on only one visit by me during the breeding season and one visit during the winter by Geoff Rogers.

--Philip Unitt

Prepare to Clear the Winter Threshold in Your Square!

Please recall that one of the criteria for the threshold goal for winter is at least one visit in at least three different winters. Therefore, the first winter in which any square can reach its winter threshold is the one coming up, the third winter of the project. Already many squares are poised on the edge of this threshold. Even if you have satisfied the criteria of at least 25 winter hours and at least 90% of the winter target number of species in the project's first two years, please make that one visit this year to clinch that last criterion. We never know what irregular species may choose 1999-2000 to stage an invasion.

Please check your number of hours to ensure you get to the 25 if you're just a little shy. If you're not sure how many hours or how many species have been recorded in winter in your square, just ask us; we can answer this question quickly out of the computer. For example, if the square lies within a Christmas Bird Count circle, there might be substantial data beyond what you've sent.

When all the criteria have been met, and you've decided to move on to other squares, concluding your work in the square where the threshold has been completed, please remember to estimate an abundance level for each species you saw. Remember, this estimate is just an order of magnitude, 1 for 1 to 10 individuals, 2 for 10 to 100, 3 for 100 to 1000, and 4 for 1000 to 10,000. It's your best estimate of how many birds of each species are actually in the square, on the basis of the amount of habitat and the numbers you observed.

For example, in covering square P22, I sometimes hike 2 miles down Scove Canyon, which is largely chaparral. On these winter hikes, I've counted 20 to 25 Fox Sparrows. Now, the Fox Sparrow is an inconspicuous species; I figure I see only those within 100 feet of the trail. So I estimate there were 20 to 25 Fox Sparrows in 2 miles X 5280 feet/mile X 200 feet (100 feet on either side of the trail) or about 2 million square feet. Each bird atlas square covers 3 by 3 miles or (3 X 5280)2 equals about 250 million square feet. Eyeballing the habitat map for the square I estimate at least half or 125 million square feet is heavy chaparral good for Fox Sparrows. So if there are 20 Fox Sparrows in 2 million square feet there should be 1250 in 125 million. So I estimate there are between 1000 and 10,000 Fox Sparrows wintering in square P22 and estimate the species' abundance level as 4.

Now, this much arithmetic isn't needed for every species; the abundance levels are coarse enough that after a couple of exercises like this you can get a more intuitive feel for a species' abundance. Most species will be more conspicuous or more localized within a square. But I offer this example in how to get a handle on a common bird.

If you have math anxiety, don't panic. Just estimate best you can, and I'll review the estimates for consistency. For many species even such a rough attempt will give us a better estimate of their numbers than has been possible previously.

--Philip Unitt

Christmas Bird Counts

are an important facet of the San Diego County Bird Atlas. Indeed, Christmas Bird Counts have contributed 19% of our winter database. Fortunately, all the count compilers and a large fraction of the count participants are also atlas participants, making this cooperation a natural one. Thanks very much to compilers Dennis Wysong, Ken Weaver, Bob Thériault, Robert Patton, and Claude Edwards for their terrific efforts on the atlas' behalf. Several squares, such as F19 (Warner Springs), M8 (San Dieguito Valley), and U11 (Chula Vista) are reaching their winter thresholds largely on the basis of Christmas Bird Counts. So please participate in as many counts as you can, contacting these organizers:

18 December, San Diego: Claude Edwards (619-563-6695)
19 December, Borrego Springs: Bob Thériault (760-767-3312)
26 December, Rancho Santa Fe: Robert Patton (858-560-0923)
27 December, Lake Henshaw: Claude Edwards (619-563-6695)
28 December, Oceanside-Vista-Carlsbad: Dennis Wysong (760-754-1264)
2 January, Escondido: Ken Weaver (760-723-2448)

Blockbuster Weekends

"Blockbuster weekends," field trips where we visit unadopted or poorly covered squares, have been important contributors to our effort. Even when we have just eight or ten participants, working in teams of two, we improve our coverage substantially. Participants are welcome for a single day or the whole weekend. While we can't guarantee anything, these weekends have generated many interesting discoveries, getting us into areas not commonly visited by birders.

8-9 January: Southern Anza-Borrego Desert. Meet on Highway S-2 at the turnoff to Bow Willow Campground (crossing of Carrizo Creek) at 7:00 AM on Saturday 17 April. Camping Saturday night at Agua Caliente County Park. Since the area entails a long drive for those of us coming over from the coast, please consider coming out Friday evening and camping over.

22-23 January: Campo/Boulevard region of southeastern San Diego County. Meet at 7:00 AM at the Buckman Springs Rest Area along Interstate 8, southeast of Pine Valley. Camping Saturday at Frank Unmack's ranch near Jacumba.

5-6 February: Oak Grove/Chihuahua Valley. Meet at 6:30 AM on Saturday 23 January at Warner Springs, in the parking lot on the west side of the road just south of the gas station. Camping at the Forest Service's Oak Grove Campground.

19-20 February: Palomar Mountain/Valley Center. Meet at 6:30 AM in Valley Center at the post office on Cole Grade Road just north of Valley Center Road. Camping at the Forest Service's Observatory Campground.

WingDing Things

Our Fall WingDing in September was a smashing success! About 150 participants gathered on the campus of Point Loma Nazarene University for a little bit of birding and a whole lot of socializing. Fall migration wasn't really happening yet, but the weather was delightful and McCullough Park overlooking the Pacific Ocean was an ideal setting for the informal picnic. After lunch, Phil gave a brief update on the project's progress and once again we were delighted to recognize breeding-season threshold-clearers. Those who cleared the threshold in at least one square received a Sierra Club engagement calendar, those who cleared it in two also received a binocular strap from La Mesa Camera, and those who cleared it in three or more squares also received a gift certificate to the Museum store. Fred Belinsky modeled one of the hats he designed for the Bird Atlas, as a preview of gifts to come. We'll be awarding Fred's hats to everyone who clears the winter season threshold!

Thanks to Barbara Anderson, Kathy Estey, Dorothy Green, Cheryl Mann, and Joan Roberts for once again helping with the check-in, to Janet Chenier of the Museum store for providing the gift certificates, to Point Loma Nazarene University and the staff of Conference Services for allowing us to hold the event in such a spectacular location, and to Marriott Catering for preparing the delicious box lunches. And we thank the National Fish and Wildlife Foundation, CalTrans, and the Zoological Society of San Diego for their financial support making the event and gifts possible.

We're already working on our next event on Sunday 26 March 2000. We'll first meet in Balboa Park's newest auditorium at the Museum of Photographic Arts for a video and slide presentation by Golden Eagle expert David Bittner and to award our winter threshold-clearers. Afterward, we'll be treated to refreshments in the Natural History Museum, in the newly opened "Dinosaurs of Jurassic Park: The Lost World" exhibit. This promises to be quite an event! Mark your calendars now!

If you clear your winter threshold, get your data in early, and attend the event, you'll go home wearing your very own Bird Atlas hat!

--Ann Klovstad

Redhead chick sketch by Nicole Perretta

Winter 1999 Wrenderings | Wrenderings Archive | Bird Atlas Introduction