Outline of Quino Recovery Plan - The Xerces Society

natural lands are absent, by costly perpetual management to restrict human
traffic, control nonnative species invasion, and augment butterfly populations.
Spatially clustered Quino checkerspot observations (see Figure 2) are called
habitat complexes in this recovery plan. Habitat complexes indicate the
approximate distribution of linked habitat patch networks within the distribution
of extant metapopulations. Metapopulation distributions (currently undescribed)
may include more than one habitat complex and are likely to be greater than the
distribution of the habitat complexes described below. Further research is
required to determine the maximum distribution of metapopulations required for
stability. Habitat considerations listed below are largely drawn from personal
observations of our staff and the Recovery Team..
Gavilan Hills habitat complex: Quino checkerspot individuals were observed in
Harford Springs County Park in 1998, a site that was once part of a more
extensive, well documented distribution (Figure 2). Quino checkerspot
butterflies were last observed at the southern margin of Lake Mathews in 1986
(Figure 2). The Quino checkerspot was historically abundant in this area, with
consistently high densities reported by collectors from the 1950's to the mid
1980's (Orsak 1978; K. Osborne and G. Pratt, pers. comm.). Therefore the
Gavilan Hills habitat complex distribution includes the vicinity of Harford
Springs park and also habitat areas south of Lake Mathews that are part of the
documented historical distribution (Figure 2).
Habitat Considerations:
The Gavilan Hills area is characterized by high-quality habitat patches with
dense, extensive stands of plantain (Plantago spp.) in open spaces, juniper
woodland, coastal sage scrub, and grassland. Landscape connectivity is
compromised primarily by Cajalco road. Landscape connectivity still exists
between Harford Springs County Park and Lake Mathews, and apparently
suitable habitat containing dense stands of plantain exists south of Lake
Mathews in the vicinity of Black Rocks, west of Monument Peak (K. Osborne,
pers. comm.). Stands of plantain also occur in the vicinities of Estelle Mountain,
Railroad Canyon Reservoir, and the town of Sun City (G. Pratt, pers. comm.). It
is possible that the Black Rocks habitat patch was a historical source of
butterflies for other habitat patches in the area (K. Osborne, pers. comm.).
10