Outline of Quino Recovery Plan - The Xerces Society

I. INTRODUCTION
A. Brief Overview
The distribution and abundance of the Quino checkerspot butterfly (Euphydryas
editha quino) have been dramatically reduced during the past century as a result
of agricultural and urban development and other land-use changes in southern
California. Immediate protection and management of the habitats that support
the species, initiation of a captive propagation program, and development of the
monitoring scheme and research agenda described in this recovery plan will be
necessary to prevent extinction of the Quino checkerspot.
The Quino checkerspot (Figure 1) is now known only from western Riverside
County, southern San Diego County, and northern Baja California, Mexico,
although the historic range of this taxon included much of coastal California
south of Ventura County and inland valleys south of the Tehachapi Mountains
(U.S. Fish and Wildlife Service database). More than 75 percent of the Quino
checkerspot’s historic range has been lost (Brown 1991, U.S. Fish and Wildlife
Service database), including more than 90 percent of the coastal mesa and bluff
distribution. Quino checkerspot populations have been reduced in number and
size by more than 95 percent range-wide primarily due to direct and indirect
human impacts including habitat loss and fragmentation, invasion of nonnative
plant species, and disrupted fire regimes (D. Bauer, D. Murphy, and M. Singer,
pers. comm.).
This recovery plan describes six geographic areas (Recovery Units) containing
habitat that supports extant Quino checkerspot populations (Figure 2, Figure 3).
Recovery Units contain both lands that are considered essential and lands that
are not considered essential to the conservation of the species. Determination of
management needs and distribution of habitat required for long-term persistence
of the species will require further surveys, monitoring, modeling, and other
research described in the recovery task portion of this document. Habitat within
the current known distribution of the species ranges from moderately to highly
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