2002
Quino checkerspot butterfly monitored reference site information
Updated: May 14, 2002
The Carlsbad Fish and Wildlife Office currently monitors eight reference sites occupied by the Quino checkerspot butterfly in western Riverside and southwestern San Diego counties. Three of the eight reference sites contain specific larval habitat patches where we have been able to consistently find larvae and focus monitoring efforts. The larval habitat patches are found at the Lake Skinner site, and a site south of Anza in Riverside County; and the Marron Valley site in San Diego County.
San Diego County Monitored Reference Site Information:
Monitored Sites:
There are four monitored sites in southwestern San Diego County, as follows: 1) the Marron Valley larval habitat patch is located on a ridge top above Marron Valley at an elevation of 2,000 feet (ft); 2) the Rancho Jamul site, located in the vicinity of the intersection of Otay Lakes Road and State Route 94 between 800-1,000 ft in elevation; 3) northeast of the Sweetwater Reservoir between 500 and 800 ft in elevation; and 4) the western slope of Otay Mountain at an elevation of 2000 ft.
Date Observations
February 13, 2002 Two adult Quino checkerspot butterflies were observed at the Marron Valley larval habitat patch.
February 25, 2002 There were 13 adult Quino checkerspot butterflies observed at the Marron Valley larval habitat patch.
March 14, 2002 Although conditions were cold and not conducive to butterfly monitoring, we did observe four adults at the monitored Marron Valley larval habitat patch, two of which appeared to be newly emerged. Several other fresh looking adults were observed on the Marron Valley ridge top.
March 26, 2002 No Quino checkerspot butterflies were observed at the monitored larval habitat patch, or at any of the other habitat patches where they have been observed this season. However, two male Quino checkerspot butterflies were observed on the Marron Valley ridge top along the road. Larval and adult abundances appear to be atypically low this season.
Habitat Conditions:
Although abundant host plants germinated during early rains, host plant abundance is currently reduced and overall host plant quality appears to be poor. Environmental conditions remain atypically dry at all reference sites in San Diego County. No adults or larvae have been observed at any of the other San Diego County reference sites. The only sites in San Diego County, other than Marron Valley, where we are currently able to detect germinated host plants are at the Rancho Jamul and Sweetwater Reservoir sites, where host plants densities are currently reduced and of poor quality. All monitored reference sites in San Diego County are generally coastal sage scrub dominated by buckwheat and chamise.
Riverside County Monitored Reference Site Information:
Monitored Sites:
There are four monitored sites in Riverside County, as follows: 1) the Lake Skinner larval habitat patch is located south of the lake on a red clay flat in a mixed community of coastal sage scrub and grassland at 1,500 ft in elevation; 2) the vicinity of Oak Mountain northwest of Vail Lake at an elevation between 2,000 and 2,600 ft; 3) west of Wilson Valley at an elevation of between 2,000 and 2,300 ft; and 4) the Anza larval habitat patch is located south of the town of Anza between 4,200 and 4,600 ft in elevation.
Date Observations
February 24, 2002 One adult male Quino checkerspot butterfly was seen at the Lake Skinner larval habitat patch
March 4, 2002 Approximately 16 adult Quino checkerspot butterflies were observed at the Lake Skinner larval habitat patch
March 10, 2002 We have not detected any germinated host plants at the Oak Mountain site, however, two male Quino checkerspot butterflies were observed on hilltops at this site.
March 13, 2002 Approximately 30 Quino checkerspot butterflies were observed at the Lake Skinner site. At the Anza larval habitat patch, the only primary host plants present are Antirrhinum coulterianum and Plantago patagonica. These host plants appeared to be in good condition, and post-diapause larvae were observed.
March 21, 2002 There were eight adult male Quino checkerspot butterflies observed at the Lake Skinner larval habitat patch; one was also observed on a nearby hilltop.
March 30, 2002 At the Anza site, eight adult male Quino checkerspot butterflies that appeared to be newly emerged were observed.
March 31, 2002 There were eight male Quino checkerspot butterflies observed at the Lake Skinner larval habitat patch. The majority of Quino checkerspot butterflies observed at this site were “worn and faded” in appearance.
April 12, 2002 No Quino checkerspot butterflies were observed at the Lake Skinner site.
April 19, 2002 No live P. patagonica plants or larvae were observed at the Lake Skinner larval habitat patch. At the Anza site, one freshly-emerged female adult Quino checkerspot butterfly, one egg cluster, and no larvae were observed. Also at the Anza site, almost no live A. coulterianum plants and only a few small live P. patagonica plants were observed.
May 2 and 8, 2002 No adult Quino checkerspots were observed at the Anza site. A number of A. coulterianum plants and P. patagonica plants were observed, and a pre-diapause larval cluster was observed on one A. coulterianum plant on May 8.
Larval and adult abundances appear atypically low this season.
Habitat Conditions:
Although abundant host plants germinated during early rains, living host plants are no longer detectable at the Lake Skinner larval habitat patch. Environmental conditions remain atypically dry at all reference sites in Riverside County. At the Wilson Valley site we detected germinating host plants early in the season, but these plants are no longer detectable. All monitored sites in Riverside County are generally coastal sage scrub dominated by buckwheat and chamise, with the exception of the one near Anza. The Anza site is redshank chaparral, with interspersed open areas dominated by buckwheat and great basin sagebrush.
We will update this as new information becomes available. Please check back on a weekly basis.