In 2002 and 2003, over 1500 square miles of southern California burned in firestorms unequaled for over a century, the largest fires since accurate records have been kept. Because of the fires’ unprecedented size, their effects on the ecosystem were unknown and unpredictable. Over 738 square miles burned in San Diego County alone, 17.4% of the county’s total area and nearly 25% of the area still covered by natural vegetation. The Cedar fire of October 2003 alone burned 436.4 square miles and was the single most pervasive disaster in San Diego history. The fires killed 17 people, compelled the evacuation of thousands, burned 2454 houses, blanketed the region under dense smoke for a week, and shut the business of the city of San Diego down for two days.

These wildfires also reignited the debate among resource managers, politicians, scientists, and the public about the strategies appropriate for people to live in the fire-prone ecosystems of southern California. This debate among vegetation and fire ecologists began in the early 1980s (Keeley 1982, Minnich 1982, Minnich and Chou 1996, Keeley 2002) but has now sprung to the forefront of the public eye and resource managers’ needs.

Areas burned in San Diego County in 2002 and 2003

In July and August 2002 the Pines fire burned 51.4 square miles mainly along the east slope of the Peninsular Ranges from Hot Springs Mountain south almost to Mount Laguna. At the time it was the San Diego County’s second-largest fire since the keeping of accurate records in 1910, exceeded only by the Laguna fire (272 square miles) of 1970. Anne Fege, then supervisor of the Cleveland National Forest, encouraged local biologists to take advantage of the opportunity to study the effects of a large wildfire. The fire came shortly after completion of field work for the San Diego County bird atlas (Unitt 2004), and many of the volunteers participating in that effort were interested in and available for following up the effects of the fire in areas they had so recently studied. So in December 2002 we began counts to evaluate the effects of that fire on birds.

The following year the Cedar fire burned all of central San Diego County from Marine Corps Air Station Miramar and the edges of the towns of Santee, Lakeside, and El Cajon east to Julian and the Laguna Mountains, meeting the zone burned in the Pines fire along Sunrise Highway in the Laguna Mountains. Confronted with this twist, we continued with the Pines fire study as designed but, with the sponsorship of California State Parks, added survey routes in the mixed coniferous/oak forest of the Cuyamaca Mountains. This habitat was touched only marginally by the Pines fire study, but because of the near isolation of the forest on the Cuyamaca Mountains from other similar forests on Volcan Mountain to the north (partly burned in the Pines fire) and the Laguna Mountains to the southeast (partly burned in the Cedar fire) and the fire’s intensity (canopy completely consumed over 90% of the forest), the effects of the fire could be especially severe there. Also, with the sponsorship of the U.S. Forest Service, we added survey routes in the Cleveland National Forest in areas burned on the coastal slope in coordination with a study to evaluate the effects of the fire on mammals in the same area. Thus the study covers the full range of habitats burned in the foothills and mountains, though it omits sage scrub at lower elevations home to such threatened species as the California Gnatcatcher (Polioptila californica) and San Diego Cactus Wren (Campylorhynchus brunneicapillus sandiegensis).

Preliminary analyses have been presented in many talks to the public and professional organizations and in the Los Angeles Audubon Society’s monthly publication, Western Tanager 75(4):1–6.

Thank you to our 38 volunteer observers, without whom a study covering so many routes would not have been possible.