Outline of Quino Recovery Plan - The Xerces Society

females and males at the end of the adult flight season is recommended, and
should not significantly affect metapopulation persistence (Cushman et al.
1994). Captured females that have already deposited most of their eggs can be
induced to produce and deposit more eggs than would naturally occur (G. Pratt,
pers. comm.). Captive augmentation facilities should also include butterfly
ranches within the distribution of extant metapopulations. Butterfly ranches
would consist of semi-natural areas designed and managed to produce high
density populations that could disperse naturally or be manually distributed to
augment extant metapopulations (B. Toon, pers. comm.).
6. Multiple Species Reserves and the Quino Checkerspot
For invertebrates, including the vast number of poorly described or undescribed
species that are undoubtedly also endangered but not listed (Redak 2000), the
quality of habitat preserved is more crucial than the extent (Ehrlich 1992). Thus
mitigation ratios based solely on acreage are not likely to be valid. However,
losses of lower quality Quino checkerspot habitat may threaten the preservation
of other species, even if butterfly populations are not likely to be jeopardized.
Euphydryas editha butterflies are good indicators of biodiversity and habitat
quality because they are closely tied to the taxonomic diversity of vegetation
(Launer and Murphy 1994); more so than, for example, birds (Ehrlich 1992).
Euphydryas editha is probably sensitive to pesticides and responsive to various
other general aspects of habitat quality that are not always apparent (Ehrlich
1992). Launer and Murphy (1994) found that if only sites supporting the largest
Euphydryas editha populations were preserved, or if portions of a site classified
as “marginal” butterfly habitat were lost, the proportion of protected plant
species dropped substantially. Also, although it is true that insect populations
typically require smaller habitat areas than populations of large vertebrates
(Ehrlich 1992), Euphydryas editha requires relatively large areas of conserved
landscape connectivity. That is, maintenance of dispersal corridors linking a
network of habitat patches over a large area will be required to conserve Quino
checkerspot metapopulations.
Undeveloped wildlands adjacent to and among Quino checkerspot
metapopulation distributions (or habitat complexes if metapopulation
distributions are not described) should be maintained because they contain
landscape connectivity essential to other species that are part of the Quino
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