WESTERN RIVERSIDE COUNTY
MULTIPLE SPECIES HABITAT CONSERVATION PLAN

• Volume 1 - The Plan
• Volume 2 - The MSHCP Reference Document
• Volume 3 - Implementing Agreement

• Volume 4 - Final EIR/EIS
• Volume 5 - Final Responses to Comments
• Nexus Report

Location: MSHCP > VOLUME 2 > INSECTS

INVERTEBRATES/INSECTS

• Delhi Sands flower-loving fly (Rhaphiomidas terminatus abdominalis)
• Quino checkerspot butterfly (Euphydryas editha quino)

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SPECIES NAME AND GROUP DESIGNATION

Common Name and Scientific Name:

Delhi Sands flower-loving fly (Rhaphiomidas terminatus abdominalis)

Status:

State: None

Federal: Endangered

GROUP DESIGNATION AND RATIONALE

Group 3

The Delhi Sands flower-loving fly is found at low numbers and is narrowly distributed within the Plan Area. This species is restricted by the distribution and availability of open habitats within the fine, sandy Delhi series soils. USFWS has identified three main population areas known to currently or to have at one time existed in the Plan Area. One is located in the northwestern corner of the Plan Area, a second is located in the Jurupa Hills, and the third is located in the Agua Mansa Industrial Center area. Because the Delhi Sands flower-loving fly requires a specific habitat type, this species will require site specific considerations, protection and enhancement of this limited habitat type, and species specific management to maintain the habitat and populations.

SPECIES CONSERVATION OBJECTIVES

The species-specific conservation objectives developed for this species are based upon the best available scientific information at the time of MSHCP preparation. Pursuant to Section 5.0 which includes Management, Monitoring and the Adaptive Management Program, the MSHCP's mitigation requirements will be monitored and analyzed to determine if they are producing the desired result. Based upon this information, the following species-specific conservation objectives will be adjusted if appropriate, as new information is gathered during Plan implementation. The Adaptive Management Program will be used to identify alternative strategies for meeting the MSHCP's general biological goals and objectives and, if necessary, adjusting future conservation strategies according to the information received.

Conservation for this species within the Plan Area will occur according to the process described in either Objective 1A, Objective 1B or Objective 1C noted below. Under Objective 1A, surveys for the Delhi Sands flower-loving fly will not be required on a project-by-project bases. Under Objectives 1B and 1C, project-by-project surveys in accordance with USFWS "Interim General Survey Guidelines for the Delhi Sands flower-loving fly" will be required. Any revisions to these Guidelines shall be approved by the County in order for it to be applicable to the requirements of the MSHCP.

Implementation of the Objectives below will provide for Conservation of the Delhi Sands flower-loving fly. Initially, the Local Permittees will utilize Objective 1B. However, During the life of the Plan, the Local Permittees may elect to utilize Objective 1A, 1B or 1C. Fulfillment of the ultimate requirements of any single one of the Objectives, 1A, 1B or 1C, in combination with the other components of the MSHCP Conservation Strategy for this species as described in the Introduction to Species Accounts, Volume II.B of the MSHCP, is anticipated to provide for Conservation for the Delhi Sands flower-loving fly.

Objective 1A

Include within the MSHCP Conservation Area, Delhi soils in at least three Core Areas, totaling 220 acres of Additional Reserve Lands. Areas to be conserved may include suitable dispersal and/or movement habitat and interconnecting linkages within the Core Areas themselves or be contiguous to areas that have already been conserved within and outside the Plan Area including locations outside the MSHCP Criteria Area or within San Bernardino County in the situation noted below.

The first priority for conservation will be within Core Areas including the three known occupied areas that include the known localities of the Delhi Sands flower-loving fly in the Plan Area. These locations include one in the northwestern corner of the Plan Area near Hamner Avenue and SR-60 (Mira Loma), one in the Jurupa Hills, and one in the Agua Mansa Industrial Center. If conservation is not feasible in these areas, those acres may be conserved in other locations within the MSHCP Plan Area and outside the Criteria Area or within San Bernardino County, subject to approval by the Wildlife Agencies and provided the other location has long-term conservation value for the species. Long-term conservation value will be measured by such factors as occupation by the Delhi Sands flower-loving fly on the lands to be conserved, presence of Delhi soils, opportunities for connectivity to other areas conserved for the species and other appropriate factors. Conservation within Riverside or San Bernardino County will be within Service identified recovery units as set forth in the Recovery Plan for the Delhi Sands flower-loving fly.

Progress toward achieving this objective will be measured and reported on an annual basis as part of the annual reporting required in Section 6.11 of the Plan. Annual reporting with respect to this Objective 1A will be in accordance with the Rough Step analysis parameters described in Section 6.7 of the Plan. For purposes of Reserve Assembly accounting in accordance with the Rough Step procedures, the baseline for analysis will be Delhi Sands flower-loving fly suitable habitat within the Criteria Area as depicted on Exhibit 11. Suitable habitat for this species is defined as Delhi soils co-occurring with coastal sage scrub, grassland and alluvial fan sage scrub (prime habitat) and Delhi soils co-occurring with agriculture (restorable habitat). In accordance with the requirements of Section 6.7 of the Plan, if Objective 1A is selected by the Local Permittees and the Rough Step rule is not met for this species during any analysis period, the Permittees must conserve appropriate lands supporting suitable habitat to bring the Plan back into the parameters of the rule prior to authorizing additional loss of suitable habitat. The total private lands acreage of suitable habitat within the Criteria Area ("TA" in rough step rule) is 810 acres. The Additional Reserve Lands acreage goal for suitable habitat "c" in rough step rule) is 220 acres. Loss of suitable habitat will be measured only within the Criteria Area. Conservation of suitable habitat will be measured inside and outside the Criteria Area as long as the Conservation meets the configuration parameters of Objective 1A as stated in the first paragraph of this Objective.

Objective 1B

With the exception of Cells 21, 22 and 55 within Area Plan Subunit 3 of the Jurupa Area Plan discussed below, include within the MSHCP Conservation Area locations within the Plan Area determined to be occupied by the Delhi Sands flower-loving fly based on the results of surveys conducted in accordance with USFWS "Interim General Survey Guidelines for the Delhi Sands flower-loving fly." Any revision to these Guidelines shall be approved by the County in order for it to be applicable to the requirements of the MSHCP. Surveys shall be conducted for future projects within the approximately 5,100 acres of mapped Delhi Soils within the Plan Area (see Exhibit 12, Delhi Sands flower-loving fly soils with Criteria Area).

It is understood that surveys would be conducted within suitable habitat areas of the mapped Delhi soils as determined by the surveying biologist. For example, according to the MSHCP database of the approximately 5,100 acres of mapped Delhi soils within the Plan Area, approximately 2,500 acres (49%) are already developed according to the MSHCP vegetation map and would not be considered to be suitable habitat. Once two years of surveys have been conducted, no further surveys shall be required. If the project site is determined to be occupied, 75 percent of the mapped Delhi Soils on site will be conserved. However, if the surveying biologist determines that distribution of habitat for the Delhi Sands flower-loving on site is not consistent with the extent of mapped Delhi Soils on site, 75 percent of such habitat on site will be conserved. The Service will be given 60 days to review and comment on the surveying biologists determination. If the Service disagrees with the determination of the surveying biologist, the applicable Local Permittee(s) and the Service will meet and confer within 10 working days to attempt to resolve the different determinations. If it is determined that 75 percent conservation on the occupied site is infeasible or the Service concurs that such conservation would not contribute to the long-term conservation of the species, conservation may occur within the conservation areas identified in Objective 1A at a ratio of three times (3:1) the mapped Delhi soils or subject to Service concurrence, the habitat of the species as identified by survey biologist on the identified occupied site. At such time asthe cumulative conservation according to the above methodology results in the conservation of 220 acres, no further surveys or conservation will be required. If surveys for future projects are conducted in accordance with USFWS Interim General Survey Guidelines within the mapped Delhi Soils within the Plan Area, not already conserved, and no new Delhi Sands flower-loving flies within the Plan Area are detected, no additional conservation within the Plan Area will be required.

Within Cells 21, 22 and 55 of Area Plan Subunit 3 of the Jurupa Area Plan, surveys shall not be required. Instead, 50 acres of Additional Reserve Lands shall be acquired within the geographic areas identified in Objective 1A and according to the reserve configuration guidance included in Objective 1A. Tracking of acreage conserved and lost within these cells shall be in accordance with the Rough Step analysis parameters described in Objective 1A. For purposes of Cells 21, 22 and 25, the total private lands acreage of suitable habitat within the Criteria Area ("TA" in Rough Step rule) is 270 acres. The Additional Reserve Lands acreage goal for suitable habitat ("C" in Rough Step rule) is 50 acres. Loss of suitable habitat will be measured only within the Criteria Area. Conservation of suitable habitat will be measured inside and outside the Criteria Area as long as the Conservation meets the configuration parameters of Objective 1A.

Objective 1C

Include within the MSHCP Conservation Area at least 50 acres of Additional Reserve Lands within the Plan Area and a combination of: 1) 80 percent of areas identified as occupied by the Delhi Sands flower-loving fly by existing data or determined to be occupied during surveys conducted in accordance with USFWS "Interim General Survey Guidelines for the Delhi Sands flower-loving fly" and any County approved revisions to these Guidelines; and 2) mitigation offsite at a ratio of 2:1 of areas determined to be occupied by existing data or protocol surveys.

Surveys shall be conducted for projects within the approximately 5,100 acres of mapped Delhi Soils within the Plan Area (see Exhibit 12, Delhi Sands flower-loving fly soils with Criteria Area). Once two years of surveys have been conducted, no further surveys shall be required. The survey area may be modified by mutual agreement of the Wildlife Agencies and the Permittee with land use authority over the proposed project area. If project surveys or existing data show occupancy of the site or a portion of the site by the Delhi Sands flower-loving fly, take of the Delhi Sands flower-loving fly on 20 percent of the occupied habitat may occur. The remaining 80 percent of the onsite habitat shall be avoided by the project applicant and managed for conservation of the species. Due to the critical condition of this species, the Wildlife Agencies and the Permittees shall focus conservation efforts in the northwestern portion of the Plan Area in areas known to be occupied by the Delhi Sands flower-loving fly. Upon the completion of the acquisition of 50 acres of Delhi Sands flower-loving fly habitat in Riverside County by the Parties, the survey and mitigation/avoidance requirements shall revert to:

1. Projects proposed on the approximately 5,100 acres of Delhi Soils within the Plan Area will conduct focused surveys using USFWS "Interim General Survey Guidelines for the Delhi Sands flower-loving fly" and any County approved revisions to these Guidelines to determine occupancy by the Delhi Sands flower-loving fly.
2. When Delhi flies are present on the project site, occupied habitat shall be mitigated at a 2:1 ratio at a location consistent with achieving long-term conservation value for the species.
3. If, prior to the conservation of the first 50 acres, a project has avoided 80 percent of the occupied habitat on the project site, the project proponent may request of the Permittee a modification of their project to allow the development of the 80 percent avoidance area. If the Permittee, with the concurrence of the Wildlife Agencies, determines that the conservation of Delhi Sands flower-loving fly habitat at an offsite location would result in equal or greater conservation value for the species than the habitat in the 80 percent onsite avoidance area and that the alternative mitigation site is at a location consistent with achieving long-term conservation value for the species, then the Permittee may authorize the loss of Delhi Sands flower-loving fly habitat on the avoidance area. The mitigation for this take shall be at a 2:1 ratio with the take area being the areas identified as the entire occupied area (i.e., mitigation includes the occupied habitat previously authorized for development) when the 80 percent onsite avoidance area was established.

Objective 2

Within the MSHCP Conservation Area, Reserve Managers shall document successful reproduction at all three Core Areas or other areas to be conserved in accordance with Objective 1, as measured by the presence/absence of pupae cases or newly emerged (teneral) individuals once a year for the first 5 years after permit issuance and then as determined to be appropriate (but not less frequently than every 8 years).

SPECIES CONSERVATION ANALYSIS

Conservation and Take Levels

As described below under Data Characterization, there are only 4 data points for the MSHCP Plan Area that are precise enough for evaluation, due in large part to low population numbers and patchy distribution. However, these data points are thought to define the population distribution within Western Riverside County. Three (75 percent) of four precision code "1" MSHCP data points would be conserved in reserve lands. These locations include one located east of the Riverside County boundary, south of Van Buren Street, west and east of Interstate 15, and north of Interstate 60 and two locations south of Agua Mansa Road, north of Wilson Street, and west of the Riverside County boundary. Additionally, there are known observations in the Jurupa Hills.

For purposes of this conservation analysis, potential habitat for the Delhi Sands flower-loving fly only includes relatively open sands of the Delhi series within the Plan Area. Portions of this microhabitat may be disturbed due to agriculture, unsuitable vegetation densities, or other causes; however, these are not limiting factors for this species. Species coverage must be concluded based on habitat preservation, population preservation, restorable habitat preservation, and monitoring and management to maintain this species.

Based on these habitats, the Plan Area supports approximately 1,463 acres (Tables 1 & 2) of Delhi soils which are not covered by development, chaparral, or riparian habitat. Approximately 502 acres of this soil type is covered by native habitats (Table 1), while the remaining 961 acres are covered by potentially restorable agricultural lands (Table 2). The Criteria Area will conserve approximately 50 acres (10 percent) of native habitats and 170 acres (18 percent) of potentially restorable habitats which occur over Delhi soils would be conserved within the MSHCP Conservation Area. It is assumed that these lands would be managed for wildlife resources including the Delhi sands flower-loving fly. Management actions will be incorporated into the conservation strategy so that habitat conditions will be maintained.

TABLE 1
SUMMARY OF HABITAT CONSERVATION FOR
DELHI SANDS FLOWER-LOVING FLY¹

Vegetation Type	MSHCP Plan Area1 (Acres)	Within MSHCP conservation Area			Outside MSHCP conservation Area
		Criteria Area2 (Acres)	Public/ Quasi-Public (Acres)	Total Within MSHCP Conservation Area (Acres)	Rural/ Mountainous (Acres)	Outside MSHCP Conservation Area (Acres)	Total Outside MSHCP Conservation Area (Acres)
Coastal Sage Scrub	129	3	18	21	83	105	108
Grassland	367	24	5	29	23	315	338
Riversidean Alluvial Fan Sage Scrub	6	0	0	0	0	6	6
TOTAL	502	27	23	50	106	426	452
1 Only includes habitats within the Plan Area which occur over Delhi soils. Developed and disturbed areas are not included. 2 Acres refer to Additional Reserve Lands to be assembled from within the Criteria Area.

TABLE 2
SUMMARY OF POTENTIALLY RESTORABLE LANDS FOR
DELHI SANDS FLOWER-LOVING FLY¹

Vegetation Type	MSHCP Plan Area1 (Acres)	Within MSHCP conservation Area			Outside MSHCP conservation Area
		Criteria Area2 (Acres)	Public/ Quasi-Public (Acres)	Total Within MSHCP Conservation Area (Acres)	Rural/ Mountainous (Acres)	Outside MSHCP Conservation Area (Acres)	Total Outside MSHCP Conservation Area (Acres)
Agricultural Land	961	166	4	170	0	791	791
TOTAL	961	166	4	170	0	791	791
1 Only includes habitats within the Plan Area which occur over Delhi soils. Developed and disturbed areas are not included. 2 Acres refer to Additional Reserve Lands to be assembled from within the Criteria Area.

MSHCP Conservation Area Configuration Issues

Nothing is known about genetic relationships or dispersal characteristics of Delhi sands flower-loving fly within its range or within the Plan Area to determine if important genetically distinct and isolated populations occur. However, it is generally thought that in the absence of data, it is best to preserve representative populations at the limits of its distribution and range, including latitude, longitude, and elevation. The MSHCP Conservation Area as it applies to the Delhi Sands flower-loving fly, consists of three preserved Core Areas of suitable soils which are listed within the three Recovery Units. These include areas west of Interstate 15, both north and south of Interstate 60; areas north of Interstate 60 and roughly east of Country Village Road; areas in the vicinity of Pyrite Road, north of Interstate 60; areas south of Sierra Avenue, north of Interstate 60; areas north and south of Aqua Mansa Road and also in the vicinity of Rubidoux Boulevard; and various areas along the Santa Ana River. Species experts for this species believe that connectivity between populations is necessary. Additionally, it is necessary to protect existing populations and allow for expansion into adjacent quality habitat and recovered habitat patches. Connectivity between populations will be necessary.

Implementation of the MSHCP, including the conservation of existing populations and habitat as described above, will maintain viable populations of the Delhi Sands flower-loving fly and facilitate recovery of the species. The current population size is unknown and censussing populations is problematic due to their brief flight period. Ensuring that the species remains viable in the MSHCP Plan Area will require a systematic monitoring and management program.

The MSHCP will conserve Core Areas and interconnecting habitat linkages that are suitable for occupation by the Delhi sands flower-loving fly. Furthermore, these Core Areas are connected to additional suitable habitat in southern San Bernardino County. Populations should remain viable in the habitat blocks.

Conservation Strategy Summary

In summary, conservation for the Delhi sands flower-loving fly will be achieved by the inclusion of at least 50 acres of primary habitat and 170 acres of restorable habitat as Conserved Habitat within three Core Areas within the MSHCP Conservation Area, totaling approximately 220 acres. This acreage may be updated based on site-specific base mapping within three years after permit issuance. The first priority for conservation will be within Core Areas including the three known point localities of the Delhi Sands flower-loving fly. These locations include one in the northwestern corner of the Plan Area near Hamner Avenue and SR-60, one in the Jurupa Hills, and one in the vicinity of the Agua Mansa Industrial Center. If conservation is infeasible in these areas, other locations within the MSHCP Plan Area and outside the Criteria Area, or within San Bernardino County, may be considered to achieve the acreage conservation requirement. If conservation occurs in these areas, it shall be demonstrated that the conserved areas will have long-term conservation value for the Delhi Sands flower-loving fly. Long-term conservation value will be measured by such factors as occupation by the fly on the lands to be conserved, presence of Delhi soils, opportunities for connectivity to other areas conserved for the fly and other factors such as may be determined by the Reserve Management Oversight Committee. Also, the MSHCP Conservation Area will include suitable dispersal and/or movement habitat and interconnecting linkages, including Delhi soils and other open habitats. These habitats will be conserved in between Core Areas or areas that have already been conserved for the Delhi Sands flower-loving fly. Within the MSHCP Conservation Area, Reserve Managers shall document successful reproduction at all three Core Areas within the MSHCP Conservation Area, or other areas to be conserved in accordance with Objective 1, as measured by the presence/absence of pupae cases or newly emerged (teneral) individuals once a year for the first five years after permit issuance and then as determined by the Reserve Management Oversight Committee as described in Section 6.6 of the MSHCP, Volume I (but not less frequently than every 8 years). Finally, the Plan Area is contiguous with suitable habitat in southern San Bernardino County.

INCIDENTAL TAKE

Approximately 452 acres (90 percent) of primary habitat over Delhi soils and 791 acres (82 percent) of potentially restorable habitat for the Delhi sands flower-loving fly would be outside the MSHCP Conservation Area and individuals within these areas will be subject to Incidental Take consistent with the Plan. One (25 percent) of the 5 precision code "1" records would be outside the MSHCP Conservation Area.

SPECIES ACCOUNT

Data Characterization

The Delhi Sands flower-loving fly is restricted to the Delhi series soils in open habitats. The currently known distribution in Riverside County is fairly well understood. The species was federally-listed as endangered on September 23, 1993 (U.S. Fish and Wildlife Service 1993) and a Recovery Plan (U.S. Fish and Wildlife Service 1997) was developed which outlines requirements for downlisting the fly. The life cycle of the Delhi Sands flower-loving fly make it difficult to study the life history and requirements of this species. Although recent studies have been conducted on the Delhi Sands flower-loving fly and related species, further studies and information are needed regarding food requirements, microhabitat needs, survivorship, dispersal requirements, socio-spatial requirements, and effectiveness of habitat restoration efforts. The MSHCP data base holds five (5) records for R. t. abdominalis. Of the five records, four (80 percent) are precision code "1" (an "x" and "y" coordinate that allows for good precision in the location) and one is precision code "4" (very imprecise location from a general area). Three of the precision code "1" records are from 1995, while one is from 1996. All records are considered recent.

Habitat and Habitat Associations

R. t. abdominalis is tied to fine, sandy soils, often with wholly or partly consolidated dunes referred to as the "Delhi" series (USFWS 1993). The fly if typically found in relatively intact, open, sparse, native habitats with less than 50 percent vegetative cover (USFWS 1997). The vegetation type, desert sand-verbena series includes Eriogonum fasciculatum, Croton californicus, Lotus scoparius, and Oenothera californica (Sawyer and Keeler-Wolf 1993). In some cases, Eriogonum fasciculatum, Heterotheca grandiflora, and Croton californicus are associated with the presence of Delhi sands flower-loving fly (Ballmer1989, USFWS 1997). In addition, Ambrosia acanthocarpa, Amsinkia intermedia, Eriastrum sapphirinum, Eriogonum thurberi, Lessingia glandulifera (USFWS 1993), and Eriastrum filifolium (Cazier 1985) have also been found in association with R. t. abdominalis.

Biogeography

The Delhi Sands flower-loving fly is restricted (endemic) to the Colton Dunes that once covered over approximately 40 square miles in northwestern Riverside and southwestern San Bernardino counties in southern California (USFWS 1997; USDA 1980, 1990) in irregular patches. The historic range of the Delhi Sands flower-loving fly likely extended over much of this area. All known extant populations of the Delhi Sands flower-loving fly occur within an 8 to 11-mile radius of each other within the counties of Riverside and San Bernardino (USFWS 1993; 1997) straddling Interstate 10 in the vicinity of Colton and Rialto, Riverside and San Bernardino counties ranging from Colton west to Mira Loma. Nearly all of the remaining habitat is privately owned and distributed largely within the vicinity of Colton, Rialto, Fontana, Ontario, and the Prado-Mira Loma area, with the most contiguous and highest quality in Colton.

Known Populations Within Western Riverside County

The distribution of the Delhi Sands flower-loving fly within Riverside County is limited to the northern portion of the County in the vicinity of Mira Loma, Jurupa, and the Agua Mansa area. The Delhi series soils extend east-west along Interstate 60 within the County of Riverside.

Key Populations in Plan Area

Although few areas of Riverside County have been surveyed for R. t. abdominalis, there are known localities in the Jurupa Hills area and within the Aqua Mansa Industrial Center. The historic range also extends west into the Mira Loma area. Known populations occur adjacent to the Prado/Mira Loma area of Riverside County. All known populations and recoverable vacant soils are considered key areas within the Western Riverside Plan Area.

Biology

Genetics/Systematics: Taxonomic studies by Sinclair, et al. (1993), Woodley (1989), and Yeates (1994) have recently included the genus Rhaphiomidas into the family Mydidae. This genus includes 19 species and 5 sub-species in southwestern United States and Mexico (Rogers and Mattoni 1993; Cazier 1985). Much study conducted on museum specimens (Coquillett 1891; Townsend 1895; Cazier 1941) placed the species into R. episcopus, R. mellifex, R. terminatus, and finally into R. abdominalis. In 1985, Cazier revised the genus and determined that R. abdominalis was a sub-species of R. terminatus. No genetic analysis studies have been conducted.

Diet and Foraging: The only observed foraging events have involved a few brief nectaring events on California buckwheat flowers (USFWS 1997). Rogers and Mattoni (1993) were unable to determine what the larval stages foraged on. It is unclear whether the early stages are herbivores, detrivores, or carnivores (USFWS 1997).

R. t. abdominalis has a long proboscis which is used for extracting nectar from flowers (USFWS 1993).

Daily/Seasonal Activity: The adult stage can only be found on the surface for a few days during the late summer, however the larval stages are present year-round in the soil. The larval stage may last for two or more years (USFWS 1997).

Rogers and Mattoni (1993) found that the females became active at 10:00 hours, regardless of cloud cover and became inactive at 18:00 hours unless ovipositing.

Reproduction and Development: The single reproductive period for R. t. abdominalis generally occurs in August and September, when the adults emerge from pupae and take flight. The males are more active than the females, probably searching for mating opportunities (USFWS 1993). The males out number the females 2:1. Eggs are deposited in sand and may number at least 50 eggs (Ballmer 1989). Oviposition locations may be tied to certain vegetation characteristics; similarly to the genus Apiocera (Cazier 1985).

Larvae develop and may spend one to two years under the surface of the sand. They develop into pupae when fully developed and emerge (USFWS 1993).

Survival: There is no information regarding survival.

Dispersal: There is not any definitive information regarding dispersal. However, there have been anecdotal observations of this species flying straight up in the air several feet and then darting out of sight (USFWS pers com 2002). This is speculated to equate dispersal behavior for this species.

Socio-Spatial Behavior: There is no information regarding socio-spatial behavior.

Community Relationships: There is no information in the literature regarding community relationships, however Argentine ants may predate on R. t. abdominalis (USFWS 1997), and asilid flies in the genera Proctocanthus and Promachus are known to prey on Rhaphiomidas flies (Rogers and Mattoni 1993; Cazier 1985). Preying mantids and native harvester ants have also been known to prey on the fly (MaryBeth Wolf - USFWS pers com) Additionally, subterranean predatory insect, reptiles, and mammals may opportunistically take R. t. abdominalis larvae and pupae.

Threats to Species

Formerly widespread over the Colton Dunes, the Delhi Sands flower-loving fly now is restricted to 12 known populations, of which 11 are small and highly vulnerable to extinction. Virtually all populations occur in small, isolated habitat patches surrounded by incompatible land uses. Extensive surveys for R. t. abdominalis by Ballmer (1989) and others (USFWS 1993, 1997) indicate that it now occupies less than 2.5 percent of the total Delhi sands available because of conversion to other uses including dairy, agriculture, etc.

The greatest threat to the Delhi Sands flower-loving fly is loss and degradation of its habitat, urban development, agricultural uses, sand mining, and invasion by exotic species. Dumping of cow manure and trash have also caused significant loss and modification of the species' habitat. Other threats include off-road vehicles and collecting.

Special Biological Considerations

The Delhi Sands flower-loving fly is endemic to the Colton Dunes (Delhi series soils) in areas that contain suitable conditions for the subterranean early stages, adult nectar sources, and adult feeding, breeding, and perching areas. Soil and climatic conditions, and other ecological and physical factors contribute to the maintenance of open sand areas within the species range.

Since the Delhi Sands flower-loving fly is endemic to the Colton Dunes and is strongly associated with the Delhi soils series, protection of this habitat is imperative for conservation of this species. Conservation needs will require protection and management of known occupied and restorable habitat, removal of exotic vegetation, and reduction of other threats to the species and/or its habitat.

LITERATURE CITED

Ballmer, G. 1989. A petition to the United States Fish and Wildlife Service (to list the Delhi Sands flower-loving fly as endangered). Riverside, California.

Cazier, M. A. 1941. A generic review of the family Apioceratidae with a revision of the North American species (Diptera-Brachycera). Amer. Mid. Nat. 25:589-631.

_____ 1985. A revision of the North American flies belonging to the genus Rhaphiomidas (Diptera: Apioceridae). Bull. Amer. Mus. Nat. Hist. 182(2):181-263.

Coquillett, D.W. 1891. A new Rhaphiomidas from California. West Amer. Sci. 7(56):84-86. (Cited in Cazier 1985).

Gall, L.F. 1985. Measuring the size of lepiopteran populations. J. Res. Lep. 24:97-116.

Hickman, J.C., ed. 1993. The Jepson manual: higher plants of California. Univ. of Calif. Press, Berkeley and Los Angeles. 1,400 pp.

Pollard, E., M.L. Hall, and T.J. Bibby. 1986. Monitoring the abundance of butterflies 1976- 1985. Inst. Err. Ecol. Onks Wood, UK.

Rogers, R. and M. Mattoni. 1993. Observations on the natural history and conservation biology of the giant flower loving flies, Rhaphiomidas (Diptera: Apioceridae). Dipterological Research 4(1-2):21-34.

Sawyer, J., and T. Keeler-Wolf. 1995. A manual of California vegetation. California Native Plant Society. Sacramento, California.

Sinclair, B. J., J. M. Cumming, and D. M. Wood. 1993. Homology and phylogenetic implications of male genitalia in Diptera-lower Brachyera. Ent. Scand. 24:407-342.

Townsend, C. H. T. 1895. On the Diptera of Baja California, including some species from adjacent regions. Proc. Calif. Acad. Sci., Ser. 2:601-607. (cited in Cazier 1985).

U. S. Fish and Wildlife Service. 1993. Endangered and threatened wildlife and plants; determination of endangered status for the Delhi Sands flower-loving fly. Federal Register 58 (183):49881-49887.

_____ 1997. Delhi Sands flower-loving fly (Rhaphiomidas terminatus abdominalis) recovery plan. U.S. Fish and Wildlife Service, Portland, OR. 51pp.

U. S. Soil Conservation Service. 1971. Soil Survey: western Riverside County. U.S. Gov. Printing Office, Washington, D.C. 188 pp.

_____ 1980. Soil survey of San Bernardino County southwestern part, California. U.S. Gov. Printing Office, Washington, D.C.

Woodley, N. E. 1989. Phylogeny and classification of the "Orthorrhapous" Brachycera. Pages 1371-1395. In J.F. McAlpine and D.M. Wood. Manual of nearctic Diptera vol. 3. Agriculture Canada 32, Ottawa, Ontario, Canada.

Yeates, D. H. 1994. The cladistics and classification of the Bombyliidae (Diptera:Asiloidea). Bull. Amer. Mus. Nat. Hist 219:1-191.

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SPECIES NAME AND GROUP DESIGNATION

Common Name and Scientific Name:

Quino checkerspot butterfly (Euphydryas editha quino)

Status:

State: None

Federal: Endangered

GROUP DESIGNATION AND RATIONALE

Group 3

The Quino checkerspot butterfly is narrowly distributed at relatively few locations within the Plan Area in suitable habitat. Although they may occur in nearly any upland habitat that is relatively open, they are also restricted by the distribution and availability of their host plants. Because of wide-spread infestation of non-native exotic weed species and habitat type conversion, much of the habitat that was once open and suitable is now densely vegetated and unsuitable. Patches of suitable habitat within larger habitat matrices are unpredictably available and distributed.

Spatially clustered Quino checkerspot butterfly observations have been organized into occurrence complexes for the purposes of conservation analysis. Occurrence complexes are known segments of short-term population distributions presumed to be within a larger distribution of metapopulations. There are 22 occurrence complexes within the Plan Area. Large and/or strategically located occurrence complexes are considered core populations. There are seven identified Core population Areas.

The Lake Mathews/Estelle Mountain portion of the Lake Mathews/Estelle Mountain/Harford Springs Core Area is unoccupied; it was historically occupied, but Quino has been extirpated. The other core populations occur in the southwestern portion of the Riverside Basin in the south and southeastern portions of the Plan Area from the vicinity of Diamond Valley Lake trending to the south and east into the Anza Valley.

Quino checkerspot requires specific habitat that is narrowly distributed, is extremely vulnerable to habitat degradation and fragmentation, and will require site specific management considerations.

SPECIES CONSERVATION OBJECTIVES

The species-specific conservation objectives developed for this species are based upon the best available scientific information at the time of MSHCP preparation. Pursuant to Section 5.0 which includes Management, Monitoring and the Adaptive Management Program, the MSHCP's mitigation requirements will be monitored and analyzed to determine if they are producing the desired result. Based upon this information, the following species-specific conservation objectives will be adjusted if appropriate, as new information is gathered during Plan implementation. The Adaptive Management Program will be used to identify alternative strategies for meeting the MSHCP's general biological goals and objectives and, if necessary, adjusting future conservation strategies according to the information received.

Objective 1

Include within the MSHCP Conservation Area at least 67,493 acres of habitat mosaic (which may include chaparral, coastal sage scrub, desert scrubs, grasslands, peninsular juniper woodland and scrub, playas and vernal pools, and Riversidean alluvial fan sage scrub habitats) supporting the seven core populations in the southwest portion of the County, including 1) the Lake Mathews/Estelle Mountain/Harford Springs Core Area (17,989 acres), 2) Warm Springs Creek Core Area (3,517 acres), 3) Johnson Ranch/Lake Skinner Core Area (8,068 acres), 4) Oak Mountain Core Area (8,737 acres), 5) Wilson Valley Core Area (9,303 acres), 6) Sage Core Area (4,462 acres), and 7) Silverado/Tule Peak Core Area (15,202 acres).

Objective 2

Include within the MSHCP Conservation Area the 12 known satellite (non-core) occurrence complexes within the following six areas: French Valley, Oak Mountain/Vail Lake, Anza Valley, Sage/Wilson Valley, Brown Canyon/Cactus Valley and Aguanga.

Objective 3

Within the MSHCP Conservation Area, maintain landscape connectivity around the Lake Mathews/Estelle Mountain/Harford Springs Core Area and between and among the core and satellite occurrence populations in the southeastern portion of the Plan Area. In the Lake Mathews Core Area, the MSHCP Conservation Area configuration will maintain landscape connectivity through native habitat between Lake Mathews, Olsen Canyon, Monument Peak, Dawson Canyon, Estelle Mountain, Bull Canyon, Steele Valley, Gavilan Hills, and Harford Springs areas. In the southwestern Riverside County area, the MSHCP Conservation Area configuration will maintain landscape connectivity through native habitat between and among the core population occurrences and the satellite occurrences in Antelope Valley and Murrieta Hot Springs area, east through the French Valley/Lake Skinner area, east to the Sage and Santa Rosa Hills area, east and south through Wilson Valley, Billy Goat Mountain, Aguanga, Tule Valley, and north to Anza and the Cahuilla Indian Reservation.

The MSHCP Conservation Area configuration will provide a connection between the Lake Mathews/Estelle Mountain/Harford Springs Core Area and the other Core Areas through the Steele Peak /North Peak North Elsinore/Warm Springs, Sedco Hills and Iodine Spring areas. Numerous roads and highways cross this connection and engineering design measures will be implemented to accommodate dispersion of butterflies throughout the Plan Area.

Objective 4

Within the MSHCP Conservation Area, Reserve Managers will document the distribution of Quino checkerspot on an annual basis.

SPECIES CONSERVATION ANALYSIS

Conservation Levels

For purposes of this conservation analysis, potential habitat for the Quino checkerspot includes a mosaic of habitats at all elevation levels within the Core Areas: chaparral, coastal sage scrub, desert scrubs, grasslands, playas and vernal pool, Riversidean alluvial fan sage scrub, and peninsular juniper woodland and scrub. Because only open portions of this habitat may be considered suitable to Quino, species coverage can not be concluded based on habitat preservation alone. Instead, species coverage must be based on a combination of population preservation, habitat mosaic preservation, and connectivity.

Based on this mosaic of habitats, the Plan Area supports approximately 109,161 acres of potential habitat for the Quino checkerspot butterfly. Table 1 shows the total conservation of potential habitat mosaic for the Quino checkerspot. Tables 2 through 8 show the conservation of potential habitat mosaic within the Lake Mathews/Estelle Mountain, Warm Springs Creek, Johnson Ranch/Lake Skinner, Oak Mountain, Wilson Valley, Sage, and Silverado Ranch/Tule Peak Core Areas, respectively. Approximately 67,493 acres (62%) of the total potential habitat mosaic, 17,989 acres (54%) of the Lake Mathews/Estelle Mountain Core Area, 3,517 acres (73%) of the Warm Springs Creek Core Area, 8,068 acres (59%) of the Johnson Ranch/Lake Skinner Core Area, 8,737 acres (67%) of the Oak Mountain Core Area, 9,303 acres (99%) of the Wilson Valley Core Area, 4,462 acres (33%) of the Sage Core Area, and 15,202 acres (73%) of the Silverado Ranch/Tule Peak Core Area would be conserved within the MSHCP Conservation Area. It is assumed that these lands would be managed for wildlife resources including the Quino checkerspot butterfly. Management actions will be incorporated into the conservation strategy so that habitat conditions will be maintained.

TABLE 1
SUMMARY OF TOTAL HABITAT CONSERVATION FOR
QUINO CHECKERSPOT BUTTERFLY

Vegetation Type	MSHCP Plan Area (Acres)	Within MSHCP conservation Area			Outside MSHCP conservation Area
		Criteria Area1 (Acres)	Public/ Quasi-Public (Acres)	Total Within MSHCP Conservation Area (Acres)	Rural/ Mountainous (Acres)	Outside MSHCP Conservation Area (Acres)	Total Outside MSHCP Conservation Area (Acres)
Chaparral	46,419	14,811	11,227	26,038	6,831	13,550	20,381
Coastal Sage Scrub	35,156	16,372	9,589	25,961	3,669	5,526	9,195
Desert Scrubs	3,911	2,429	809	3,238	0	673	673
Grassland	22,209	6,515	4,800	11,315	1,318	9,576	10,894
Peninsular Juniper Woodland and Scrub	686	120	183	303	4	379	383
Playas and Vernal Pools	16	0	16	16	0	0	0
Riversidean Alluvial Fan Sage Scrub	764	594	28	622	40	102	142
TOTAL	109,161	40,841	26,652	67,493	11,862	29,806	41,668
1 Acres refer to Additional Reserve Lands to be assembled from within the Criteria Area.

TABLE 2
SUMMARY OF LAKE MATHEWS/ESTELLE MOUNTAIN CORE AREA
HABITAT CONSERVATION FOR QUINO CHECKERSPOT BUTTERFLY

Vegetation Type	MSHCP Plan Area (Acres)	Within MSHCP conservation Area			Outside MSHCP conservation Area
		Criteria Area1 (Acres)	Public/ Quasi-Public (Acres)	Total Within MSHCP Conservation Area (Acres)	Rural/ Mountainous (Acres)	Outside MSHCP Conservation Area (Acres)	Total Outside MSHCP Conservation Area (Acres)
Chaparral	9,613	1,616	905	2,521	2,371	4,721	7,092
Coastal Sage Scrub	15,678	4,903	6,106	11,009	2,704	1,965	4,669
Grassland	7,344	719	3,311	4,030	272	3,042	3,314
Peninsular Juniper Woodland and Scrub	683	118	182	300	4	379	383
Riversidean Alluvial Fan Sage Scrub	182	126	3	129	40	13	53
TOTAL	33,500	7,482	10,507	17,989	5,391	10,120	15,511
1 Acres refer to Additional Reserve Lands to be assembled from within the Criteria Area.

TABLE 3
SUMMARY OF WARM SPRINGS CREEK CORE AREA
HABITAT CONSERVATION FOR QUINO CHECKERSPOT BUTTERFLY

Vegetation Type	MSHCP Plan Area (Acres)	Within MSHCP conservation Area			Outside MSHCP conservation Area
		Criteria Area1 (Acres)	Public/ Quasi-Public (Acres)	Total Within MSHCP Conservation Area (Acres)	Rural/ Mountainous (Acres)	Outside MSHCP Conservation Area (Acres)	Total Outside MSHCP Conservation Area (Acres)
Chaparral	1,621	1,161	115	1,276	0	345	345
Coastal Sage Scrub	1,369	1,046	71	1,117	0	252	252
Grassland	1,832	1,090	34	1,124	0	708	708
TOTAL	4,822	3,297	220	3,517	0	1,305	1,305
1 Acres refer to Additional Reserve Lands to be assembled from within the Criteria Area.

TABLE 4
SUMMARY OF JOHNSON RANCH/LAKE SKINNER CORE AREA
HABITAT CONSERVATION FOR QUINO CHECKERSPOT BUTTERFLY

Vegetation Type	MSHCP Plan Area (Acres)	Within MSHCP conservation Area			Outside MSHCP conservation Area
		Criteria Area1 (Acres)	Public/ Quasi-Public (Acres)	Total Within MSHCP Conservation Area (Acres)	Rural/ Mountainous (Acres)	Outside MSHCP Conservation Area (Acres)	Total Outside MSHCP Conservation Area (Acres)
Chaparral	3,238	637	1,243	1,880	1,017	341	1,358
Coastal Sage Scrub	5,029	1,231	2,240	3,471	242	1,316	1,558
Grassland	5,452	1,434	1,260	2,694	307	2,451	2,758
Playas and Vernal Pools	16	0	16	16	0	0	0
Riversidean Alluvial Fan Sage Scrub	40	3	4	7	0	33	33
TOTAL	13,775	3,305	4,763	8,068	1,566	4,141	5,707
1 Acres refer to Additional Reserve Lands to be assembled from within the Criteria Area.

TABLE 5
SUMMARY OF OAK MOUNTAIN CORE AREA HABITAT CONSERVATION FOR
QUINO CHECKERSPOT BUTTERFLY

Vegetation Type	MSHCP Plan Area (Acres)	Within MSHCP conservation Area			Outside MSHCP conservation Area
		Criteria Area1 (Acres)	Public/ Quasi-Public (Acres)	Total Within MSHCP Conservation Area (Acres)	Rural/ Mountainous (Acres)	Outside MSHCP Conservation Area (Acres)	Total Outside MSHCP Conservation Area (Acres)
Chaparral	4,769	2,734	241	2,975	236	1,558	1,794
Coastal Sage Scrub	6,252	4,194	710	4,904	170	1,178	1,348
Grassland	1,716	549	36	585	3	1,128	1,131
Riversidean Alluvial Fan Sage Scrub	291	273	0	273	0	18	18
TOTAL	13,028	7,750	987	8,737	409	3,882	4,291
1 Acres refer to Additional Reserve Lands to be assembled from within the Criteria Area.

TABLE 6
SUMMARY OF WILSON VALLEY CORE AREA
HABITAT CONSERVATION FOR
QUINO CHECKERSPOT BUTTERFLY

Vegetation Type	MSHCP Plan Area (Acres)	Within MSHCP conservation Area			Outside MSHCP conservation Area
		Criteria Area1 (Acres)	Public/ Quasi-Public (Acres)	Total Within MSHCP Conservation Area (Acres)	Rural/ Mountainous (Acres)	Outside MSHCP Conservation Area (Acres)	Total Outside MSHCP Conservation Area (Acres)
Chaparral	3,079	3,050	233	3,053	0	26	26
Coastal Sage Scrub	3,779	3,363	370	3,733	1	45	46
Desert Scrubs	1,428	1,428	0	1,428	0	0	0
Grassland	927	884	13	897	0	30	30
Peninsular Juniper Woodland and Scrub	2	2	0	2	0	0	0
Riversidean Alluvial Fan Sage Scrub	190	178	12	190	0	0	0
TOTAL	9,405	8,905	628	9,303	1	101	102
1 Acres refer to Additional Reserve Lands to be assembled from within the Criteria Area.

TABLE 7
SUMMARY OF SAGE CORE AREA
HABITAT CONSERVATION FOR QUINO CHECKERSPOT BUTTERFLY

Vegetation Type	MSHCP Plan Area (Acres)	Within MSHCP conservation Area			Outside MSHCP conservation Area
		Criteria Area1 (Acres)	Public/ Quasi-Public (Acres)	Total Within MSHCP Conservation Area (Acres)	Rural/ Mountainous (Acres)	Outside MSHCP Conservation Area (Acres)	Total Outside MSHCP Conservation Area (Acres)
Chaparral	6,828	1,614	45	1,686	3,207	1,935	5,142
Coastal Sage Scrub	2,993	1,635	78	1,713	553	727	1,280
Desert Scrubs	168	168	0	168	0	0	0
Grassland	3,472	895	0	895	736	1,841	2,577
TOTAL	13,461	4,312	123	4,462	4,496	4,503	8,999
1 Acres refer to Additional Reserve Lands to be assembled from within the Criteria Area.

TABLE 8
SUMMARY OF SILVERADO/TULE PEAK CORE AREA
HABITAT CONSERVATION FOR
QUINO CHECKERSPOT BUTTERFLY

Vegetation Type	MSHCP Plan Area (Acres)	Within MSHCP conservation Area			Outside MSHCP conservation Area
		Criteria Area1 (Acres)	Public/ Quasi-Public (Acres)	Total Within MSHCP Conservation Area (Acres)	Rural/ Mountainous (Acres)	Outside MSHCP Conservation Area (Acres)	Total Outside MSHCP Conservation Area (Acres)
Chaparral	17,066	3,999	8,443	12,442	0	4,624	4,624
Coastal Sage Scrub	56	0	13	13	0	43	43
Desert Scrubs	2,315	833	809	1,642	0	673	673
Grassland	1,466	945	146	1,091	0	375	375
Riversidean Alluvial Fan Sage Scrub	27	14	0	14	0	13	13
TOTAL	20,930	5,791	9,411	15,202	0	5,728	5,728
1 Acres refer to Additional Reserve Lands to be assembled from within the Criteria Area.

As described below under Data Characterization, 85 of the 118 database locations have a precision code of "1," and 27 would have a precision code of "2". Of these 118 locations, 113 are known from 1990 to the present. Of the 113 recent and precise locations, 80 (71%) would be within the MSHCP Conservation Area.

For this species, it is also important to consider data older than 1990 from the Lake Mathews area. Because nearly all of the information from this area is considered old (mostly from the 1970's and 1980's) but indicates an important historical population, preservation of historical populations must be considered. Of the 212 "old" documented, precision code "1" butterflies, 184 (87%) of them are preserved within the MSHCP Conservation Area. A majority of these (155 butterflies censused from 1975, 1976, 1980, and 1982) stem from four data points on the southeastern shore of Lake Mathews. The presence of Quino checkerspot butterflies from the nearby Gavillan Hills, suggests that relic populations may still exist near Lake Mathews, or re-colonization of the area is possible.

MSHCP Conservation Area Configuration Issues

Nothing is known about genetic relationships between Quino checkerspot butterfly within its range or within the Plan Area to determine if important genetically distinct and isolated populations occur. However, it is generally thought that in the absence of data, it is best to preserve representative populations at the limits of its distribution and range, including latitude, longitude, and elevation. For this species, it is particularly important to protect all core occupied and potentially occupied habitats at the limits of its distribution. This species is considered to be a meta-population species whose survival strategy is to have multiple populations distributed throughout its range at various locations. Some blink in and out of existence depending on climatic conditions or other factors. By being widely distributed, the chance of extirpation due to extreme events is reduced. Accordingly, large habitat blocks (Core Areas) important to the Quino checkerspot, are distributed throughout the MSHCP Conservation Area. The MSHCP Conservation Area as it applies to the Quino checkerspot, is anticipated to protect seven large Core Areas with six core Quino checkerspot populations, one presumed currently unoccupied Core Area and at least 12 other non-core satellite occurrence complexes. These areas include the Lake Mathews/Estelle Mountain/Harford Springs Core Area (Existing Core C plus Proposed Extended Core 2 and Proposed Core 1; 33,500 acres), Warm Springs Creek Core Area (Proposed Core 2; 4,822 acres), Johnson Ranch/Lake Skinner Core Area (Existing Cores E and J, Proposed Core 2, Proposed Extended Cores 5, 6, and 7, and Existing Constrained Linkages A and E; 13,775 acres), Oak Mountain Core Area (western portion of Proposed Core 7; 13,028 acres), Wilson Valley Core Area (central portion of Proposed Core 7; 9,405 acres), Sage Core Area (northern portion of Proposed Core 7 and southern tip of Proposed Core 4; 13,461 acres), Silverado/Tule Peak Core area (Existing Core L and Proposed Core6; 20,930 acres), and 12 known satellite populations in the vicinity of French valley, Oak Mountain/Vail Lake, Anza Valley, Sage/Wilson Valley, Brown Canyon/Cactus Valley, and Aguanga. The assumed currently unoccupied Lake Mathews core population area includes Lake Mathews, Dawson Canyon, Estelle Mountain, Lee Lake, Gavilan Plateau, Gavilan Hills, Good Hope, Meade Valley, and environs.

In addition, linkages between the Core Areas will be conserved. It is assumed that Quino checkersport can disperse up to one kilometer (USFWS 2002). In nearly all cases, the linkages would include potential habitat for Quino checkerspot butterflies. Because this species functions as a metapopulation, connectivity between the satellite populations within any given core is necessary, but connectivity between all of the cores is not necessary, or generally feasible given the current level of intervening development. However, as proposed, all of the Core Areas are connected to one another. Some by tenuous means, while other connections are more robust. The Lake Mathews Core Area is generally connected to the Warm Springs Creek Core Area by Proposed Linkages 3 and 8, Proposed Core 1, and Constrained Linkage 16. The main Proposed and Existing Cores associated with the Warm Springs Creek and Lake Skinner/Johnson Ranch Core Areas are connected by Proposed Constrained Linkages 17 and 18, and Existing Constrained Linkages A and E. These, in turn, are connected to the Sage Core Area by either Proposed Linkage 13 or Proposed Linkage 14 and the northern portion of Proposed Core 4. The Sage, Oak Mountain, and Wilson Creek Core Areas all interconnected by Proposed Core 7. These three are also connected to the Silverado/Tule Peak Core Area by the eastern portion of Proposed Core 7 and Proposed Linkage 16, or eastern portion of Proposed Core 7 and Existing Core L.

Movement across large roads and freeways will cause potentially heavy mortality in Quino checkerspot. At a minimum, studies will need to be completed to verify that the only effective means to convey Quino checkerspot across busy roadways is to install large wildlife overcrossings as theorized. These studies will hopefully determine if Quino checkerspot can successfully utilize undercrossings as well. Regardless, obvious constraints to Quino checkerspot movement will occur at locations where linkages and Core Areas cross busy roadways. Apparently constrained areas minimally occur between the Lake Mathews Core Area and the Warm Springs Creek Core Area across Highway 74 and Interstate 215; between the Warm Springs Creek Core Area and Lake Skinner/Johnson Ranch Core Area across Highway 79; and between the Sage, Oak Mountain, and Wilson Creek Core Areas and Silverado/Tule Peak Core Area across Highway 371. In addition, numerous other busy surface roads currently cross the various Core Areas and satellite areas.

Implementation of the MSHCP, including the conservation of existing core populations and other suitable habitat mosaics within Core Areas as described above, will maintain viable populations of the Quino checkerspot butterfly. The current population size is unknown, though the extent of their range within western Riverside County is thought to be well understood, and censussing populations may be difficult due to their brief and variable flight period and reliance on adequate host plant growing conditions (variables such as soil temperature; rainfall amount, timing, and distribution; evaporation rate; frost amount; and other factors determine plant growth). Ensuring that the species remains viable in the MSHCP Plan Area will require a systematic monitoring and management program.

The MSHCP will conserve large Core Areas and interconnecting habitat linkages that are suitable for occupation by the Quino checkerspot butterfly in the large habitat blocks discussed above. Populations should remain viable in the habitat blocks. Smaller occupied areas, as listed above, may be at higher risk of extirpation either rapidly as a result of some catastrophic event, or over the longer term as a result of demographic or genetic stochasticity (e.g., random birth and death rates, inbreeding depression, genetic drift) or through indirect impacts (e.g., loss of suitable requisite larval plants and nectaring plants) due to surrounding urbanization or climatic conditions.

Conservation Strategy Summary

In summary, conservation for the Quino checkerspot butterfly will be achieved by the inclusion of at least 67,493 acres of Core Area including suitable Conserved Habitat mosaic within seven Core Areas and an additional 12 satellite locations. These areas are composed of large blocks of habitat within the MSHCP Conservation Area. The Core Areas are provided with numerous connections of Proposed and Existing Cores. Potential dispersion inhibitors, such as busy roads and highways, will be modified by engineers to accommodate movement of the species. In addition, the MSHCP Plan will document the distribution of Quino checkerspot on an annual basis. The current population size of the Quino checkerspot is unknown, but the general distribution is, and a relatively sizable database is present within the UCR database. Furthermore, the Plan Area is contiguous with suitable habitat in eastern San Diego County.

INCIDENTAL TAKE

Approximately 41,668 acres (38%) of potential habitat mosaic within the Core Area (15,511 acres [46%] in the Lake Mathews/Estelle Mountain Core Area; 1,305 acres [27%] in the Warm Springs Core Area; 5,707 acres41%] in the Johnson Ranch/Lake Skinner Core Area; 4,291 acres [33%] acres in the Oak Mountain Core Area; 102 acres (1%) in the Wilson Valley Core Area; 8,999 acres [67%] of the Sage Core Area, and; 5,728 acres [27%] of the Silverado/Tule Peak Core Area) for the quino checkerspot would be outside the MSHCP Conservation Area and individuals within these areas will be subject to Incidental Take consistent with the Plan. Twenty-seven (32%) of the 85 precision code "1" or "2" records would be outside the MSHCP Conservation Area. However of these, three (11%) are mapped within existing agriculture and one (4%) are located in developed or disturbed habitat coverages.

SPECIES ACCOUNT

Data Characterization

The MSHCP data base includes U.C. Riverside database holds 118 data points representing Quino checkerspot butterfly detections. These data points range from 1982 through 2001. Of the 118 locations, 85 (72%) are precision code "1" (an "x" and "y" coordinate that allows for good precision in the location), 27 (23%) are precision code "2" (one "x" or "y" or equivalent). The remaining 6 (1%) are precision code "3" and "4" (imprecise locations from general areas). Nearly all of the records are relatively recent, with 107 (96%) of the precision code "1" and "2" butterflies occurring since 1990 and 5 (4%) pre-1990. Abundant pre-1982 data was not included within the database, however data is available which dates back to 1934.

The older records tend to be clustered around the Lake Mathews/Gavilan Hills area, while newer records are typically clustered in the Wildomar, Murrietta Hot Springs, Lake Skinner, Murietta, French Valley, Quail Valley, Black Hills/Vail Lake, Rancho California, Wilson Creek/Wilson Valley, Cactus Valley, Aguanga, and Cahuilla Indian Reservation areas with outliers in the extreme northcentral portion of the Plan Area (Reche Canyon) from 1998 and junction of Highway 74 and Highway 371. In general, the known historical and current population in western Riverside County runs through the basin from Lake Mathews, southeast to Vail Lake, and then east through the desert transitional habitats and east of Anza. Records are generally lacking from the higher elevations of the Santa Ana Mountains and San Jacinto Mountains.

A relatively large, and growing, body of biological information exists for the Euphydryas editha sp.; however, this information may or may not be applicable to the Quino subspecies. During the 1997 through 2002 survey seasons, new populations were discovered in western Riverside County in areas of large unfragmented native habitat.

A draft Recovery Plan (U.S. Fish and Wildlife Service 2000) was developed in 2000 and finalCritical Habitat (U.S. Fish and Wildlife Service 2002) was designated in April 2002. The draft Recovery Plan outlines the conditions under which the Quino checkerspot may be down-listed/de-listed while the Critical Habitat document, specifically outlines those areas deemed necessary to species recovery.

Habitat and Habitat Associations

The Quino checkerspot butterfly (QCB) has two distinctive phases in its life history: early stages (egg, larva or caterpillar, and the pupa or chrysalis) and adult. Each phase has distinct habitat requirements. Habitat associations seem to be tied to both host plant species and topography. Larvae feed immediately upon Plantago erecta, Plantago patagonia, Antirrhinum coulterianum, Cordylanthus rigidus (USFWS 2001, USFWS 2002) and possibly other Plantago species and Collinsia concolor, and Castilleja exserta which have been shown to support larvae in the laboratory (Pratt, unpubl. data). Additionally, Collinsia spp. and Castilleja spp. are larval food plants for other Euphydryas editha subspecies (Singer 1971, 1972, 1982, White 1974, Garth and Tilden, 1986). After diapause, the larvae feed again on Plantago erecta before metamorphosing. After metamorphose, the adults nectar mostly on small annuals.

Adult QCB often occur on open or sparsely vegetated rounded hilltops, ridgelines, and occasionally rocky outcrops. Adults have been observed sunning themselves at the bases of hills, and they have been observed flying through disturbed areas, apparently dispersing to sites possessing larval food plants and/or nectar sources.

Micro and macro topography appear to influence Euphydryas editha development and distribution (Weiss, et al. 1988); larvae and adults have been detected on warmer south-facing slopes early in the season, whereas later in the season they were detected on cooler north-facing slopes. QCB populations appear to be associated with loamy soils with moderate to high amounts of clay, located within sparsely vegetated areas that contain potential host plants and nectar sources, and generally a moderate to high percentage of native plants. However, QCB have also been found along desert transition on decomposed granite soils (Pratt, pers. comm.). Topographically diverse sites, including areas with ridges, rounded hilltops, are very likely important for the long-term persistence of populations (Weiss, et al. 1988; Pratt, pers. comm.). The habitat components have been found in association with, but not restricted to vernal pools, sage scrub, chaparral, native and non-native grassland, and open oak and juniper woodland communities. The key component seems to be open-canopied habitats.

Biogeography

The historic range of the QCB extends from the Santa Monica Mountains and Santa Clarita Valley east and south along the foothills of the Transverse and Peninsular ranges in California, and south into northwestern Baja California, Mexico. Adults have been recorded from Point Dume and Dana Point in Los Angeles and Orange Counties, respectively, to approximately 1,500 meters (5,000 feet) in the Anza region of southwestern Riverside County, California (Mattoni, et al. 1997; Pratt unpubl. data).

Extant populations of the butterfly are currently known from western Riverside County and southern San Diego County, California, and northwestern Baja California, Mexico (Mattoni, et al. 1997).

Known Populations Within Western Riverside County

Historically, butterfly colonies were found in the Lake Mathews region and in the central western region of Riverside County. Currently one known colony exists in the Harford Springs Regional Park, in the northwestern part of the County. The remainder of the distribution within western Riverside County, occurs in the southern and eastern portions of the County. Butterfly populations have been documented ranging from just east of Interstate 15, east towards the Hogbacks through the Warms Springs Creek area, and east to the Southwestern Riverside County Multiple Species Reserve and beyond. The Crowne Hill Property in Temecula supports a population. Other populations are found east through to Vail Lake and through the Sage/Aquanga region and finally ending in the Durasno Valley (U.S. Fish and Wildlife Service unpublished data 1998, MSHCP data).

Key Populations in Plan Area

Key populations include all currently known populations including those in the vicinity of Aguanga, Anza, Cactus Valley, Gavilan Hills, Menifee, Murrieta Hot Springs, Sage, Vail Lake, Wildomar, Wilson Valley, Paloma Valley, Kolb Creek, and Lake Skinner Reserve. In addition, a key population in the Lake Mathews area is based on historical occupance, nearby populations (circa 1998) and amount of available habitat.

Biology

Genetics/Systematics: E. e. quino was first designated as Melitaea quino (Behr 1863), then later considered to be Euphydryas (Comstock 1927), followed by confusing nomenclature discrepancies indicating that it was E. e. wrightii. The nomenclature has confused it with E. chalcedona hennei and Thessalina leanira wrightii. All are differentiated through wing patterns and coloration and abdomen patterns. E. e. quino is joined by three other subspecies which are differentiated from it by temporal or elevational segregation, or larval host plant differences (Mattoni, et al. 1997, Ballmer, et al. pers com. 2000).

The only genetic analysis conducted on quino checkerspot determined that it was more closely related to E. editha than the other three subspecies (Braughman, et al. 1990; Mattoni, et al. 1997).

Diet and Foraging: Larvae feed on plantain (Plantago erecta), and possibly Antirrhinum coulterianum, Collinsia concolor, and Castilleja exserta (Pratt, unpubl. data). Collinsia spp. and Castilleja spp. are larval food plants for other Euphydryas editha subspecies (Singer 1971, 1972, 1982, White 1974, Garth and Tilden, 1986). After termination of diapause caused by late fall or winter rains, larvae feed on Plantago erecta and then enter their pupal stage. The adults nectar mostly on small annuals including Lasthenia ssp., Cryptantha ssp., Gilia ssp., Linanthus dianthiflora, Salvia columbariae, annual Lotus spp., and Eriodictyon ssp. (Murphy, et al. 1983, Mattoni, et al. 1997).

Daily/Seasonal Activity: Adults fly from approximately mid-February to mid-May, depending on weather and elevation.

Reproduction and Development: E. e. quino mate only once, after which the male utilizes a mucus plug to deter further copulations (Labine 1964). Female E. e. quino lay egg masses ranging from 20-180 eggs (Pratt, unpubl. data; Singer 1971, 1972, 1982; White 1974; Garth and Tilden, 1986; Mattoni, et al. 1997); however, a minimum number of 39 was determined by Ehrlich, et al. (1975). Total egg production ranges from 400 to 800 by an individual during a season (lifetime). Eggs hatch in 7-10 days (Murphy, et al. 1983; Mattoni, et al. 1997) and larvae begin to feed immediately on Plantago erecta among other potential host species (Pratt, unpubl. data; Singer 1971, 1972, 1982; White 1974; Garth and Tilden, 1986; Mattoni, et al. 1997). During the third and fourth instar, larvae enter into an obligatory diapause which corresponds with food plant senescence. Diapause may extend for several to many years in response to drought or adverse conditions (G. Pratt, pers. obs.; Mattoni, et al. 1997). After termination of diapause caused by late fall or winter rains, larvae feed and then enter their pupal stage or re-enter diapause. The adults emerge in approximately two weeks, nectar mostly on small annuals, disperse, reproduce, and then die. Adult nectar plants play a significant role in Euphydryas editha egg production and population dynamics (Murphy, et al. 1983).

Survival: Mattoni, et al. (1997) proposed that once larvae enter diapause, their survival rates increase. Singer (1972) attributed most mortality to lack of host plants. It was estimated that nearly 99% of the prediapause cohort died during the years studied by them. Singer and Erlich (1979) purported that weather was the main factor determining survival rates in prediapausal larvae. If weather patterns did not allow for host plant growth, then larvae starved or did not grow rapidly enough and therefore did not survive. They found that the prediapausal larvae survived when Plantago erecta would remain green for five weeks after eggs were laid; if eggs were laid on Plantago erecta that was growing over Botta's pocket gopher- (Thomomys bottae) tilled soil; or if larvae were able to locate a secondary host plant.

Dispersal: Metapopulation dynamics play an important role in the regional persistence of E. e. quino. As defined by Murphy (1988), "A metapopulation is a population of populations, which is dependent on a persistent reservoir population to provide colonists to habitat supporting satellite populations which will frequently go extinct due to natural environmental causes such as drought. The loss of a single reservoir population may precipitate the collapse to extinction of an entire metapopulation. The loss of particular satellite populations [through permanent means such as development or a catastrophic permanent event], may interrupt the natural stepping stone re-colonization process to other outlying populations." Therefore, an important consideration of E. e. quino persistence is the distribution of occupied and suitable habitat on the landscape.

Due to the sedentary nature of Euphydryas, (USFWS 1997) maintaining stepping stone connections between the satellite and source colonies will be integral to maintaining the survival of the western Riverside metapopulation. Evidence from the Bay checkerspot (e.g., Ehrlich, et al. 1975, Ehrlich 1961, Ehrlich and Murphy 1981) suggests that successful long-distance dispersal is extremely rare. In fact, many Quino experts believe that populations separated by more than two miles are demographically isolated (Mattoni, et al. 1997, Faulkner pers. comm., Nagano pers. comm.). Maintaining connections of less than two miles between satellite and source colonies likely will be necessary for the continued survival of the Quino checkerspot butterfly. However, the USFWS (2002) used a one kilometer dispersal distance when determining Critical Habitat Blocks.

Community Relationships: E. e. quino is parasitized by tachinid flies, and may be predated on by spiders, ants, and carabid beetles (Mattoni, et al. 1997).

Threats to Species

The Quino checkerspot butterfly may have been one of the most abundant butterflies in coastal southern California until the 1950's. Habitat degradation and destruction has resulted in a dramatic decline in the species to a point where it currently is in danger of extinction. The animal also is endangered by displacement of the larvae food plants and adult nectar sources by invasive non-native vegetation, non-native invertebrates such as earwigs and sowbugs, over-grazing, poorly planned fire management practices, extreme adverse weather, over-collection by butterfly collectors, and off-road vehicle activity. Fragmentation of habitat and isolation of populations may be the largest threat to the Quino. Also, the effects of global warming should be carefully evaluated when determining the proximate cause of Quino checkerspot decline (Mattoni, et al. 1997).

Special Biological Considerations

Metapopulation dynamics plays an important role in the regional persistence of E. e. quino. Therefore, an important consideration of Quino survival is the distribution of occupied and suitable habitat on the landscape. Fragmentation appears to be a limiting factor for Quino checkerspot survival as the host plant seems readily available throughout the species historic range. Those areas in which the butterfly historically existed are now fragmented by development and agriculture. The areas in which the butterfly is currently found in the County are the remaining large contiguous blocks of native habitat (USFWS unpublished data).

Due to the sedentary nature of Euphydryas, maintaining stepping stone connections between the satellite and source colonies will be integral to maintaining the survival of the western Riverside metapopulation. Successful long-distance dispersal is probably extremely rare. In fact, many Quino experts believe that populations separated by more than two miles are demographically isolated (Mattoni, et al. 1997, Faulkner pers. comm., Nagano pers. comm.). Maintaining connections of less than two miles between satellite and source colonies likely will be necessary for the continued survival of the Quino checkerspot butterfly.

LITERATURE CITED

Ballmer, G, D. Hawks, K. Osborne, and G. Pratt. 2000. The quino checkerspot butterfly, Euphydryas editha quino. Symposium paper. 7pp.

Behr, H. 1863. Proc. California Acad. Nat. Sci. 3:90.

Comstock, J.A. 1927. Butterflies of California. Published by Author, Los Angeles, California. Ehrlich, P.R. 1961. Intrinsic Barriers to Dispersal in Checkerspot Butterfly. Science 134: 108-109.

Ehrlich, P.R., R.R. White, M.C. Singer, S.W. Mckechnie & L.E. Gilbert. 1975. Checkerspot butterflies: a historical perspective. Science 118: 221-228.

Ehrlich, P.R. and D.D. Murphy. 1981. The Population Biology of Checkerspot Butterflies (Euphydryas). Biol. Zbl 100: 67-69.

Gall, L.F. 1985. Measuring the size of lepiopteran populations. J. Res. Lep. 24:97-116.

Garth, J. S. and J. W. Tilden. 1986. California Butterflies. University of California Press, Berkeley, California, 246 pp.

Labine, P.A. 1964. Population biology of the butterfly, Euphydryas editha. I. Barriers to multiple inseminations. Evolution 18:335-336.

Mattoni, R., G. Pratt, T. Longcore, J. Emmel, and J. George. 1997. The endangered Quino checkerspot butterfly, Euphydryas editha quino (Lepidoptera: Nymphalidae). J. Res. Lep. 34:99-118.

Murphy, D.D., A.E. Launer, and P.R. Erlich. 1983. The role of adult feeding in egg production and population dynamics of the checkerspot butterfly Euphydryas editha. Oecologia 56:257-263.

Singer, M.C. 1971. Evolution of food-plant preference in the butterfly Euphydryas editha. Evolution 25:383-389.

Singer, M.C. 1972. Complex components of habitat suitability within a butterfly colony. Science 176:75-79.

Singer, M.C. 1982. Quantification of host preferences by manipulation of oviposition behavior in the butterfly Euphydryas editha. Oecologia 52:224-229.

U. S. Fish and Wildlife Service. 1997. Endangered and threatened wildlife and plants: determination of endangered status for the Laguna Mountain Skipper and Quino checkerspot butterfly. Federal Register 62:2313-2322.

U. S. Fish and Wildlife Service. 2000. Draft recovery plan for the Quino checkerspot butterfly (Euphydryas editha quino). Portland, Oregon. x + 123 pp.

U. S. Fish and Wildlife Service. 2001. Endangered and threatened wildlife and plants: Proposed determination of critical habitat for the Quino checkerspot butterfly. Federal Register 66:9476-9507.

U. S. Fish and Wildlife Service. 2002. Endangered and threatened wildlife and plants: Designation of critical habitat for the Quino checkerspot butterfly (Euphydryas editha quino); Final Rule. Federal Register 67:18356-18395.

Weiss, S. B., D.D. Murphy, and R. R. White. 1988. Sun, slope, and butterflies: topographic determinants of habitat quality for Euphydryas editha. Ecology 69:1486:1496.

White, R.R. 1974. Food Plant defoliation and larval starvation of Euphydryas editha. Oecologia 14:307-315.

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