Rancho Santa Ana Botanic Garden
1500 North College Avenue, Claremont, CA 91711. (909) 625-8767

and James D. Morefield, Nevada Natural Heritage Program (see below)

status report prepared for

Nevada Natural Heritage Program, Department of Conservation and Natural Resources,
901 South Stewart Street suite 5002, Carson City, NV 89701-5245. (775) 684-2900

and

U.S. Fish & Wildlife Service, Nevada State Office
4600 Kietzke Lane, C-125, Reno, NV 89502. (702) 784-5227

with Section-6 funds provided through Project Agreement EP-3-8

SUMMARY: Arctomecon californica was first discovered in 1844 near Las Vegas, Clark County, Nevada, by John Charles Frémont on his second expedition through the American West, and was described as a new species the following year by John Torrey and Frémont, who named it for the Mexican territory where it was found. All three known species of this distinctive genus of the poppy family are endemic to the northern Mojave Desert. As of 1992, Arctomecon californica had been reported from about 52 populations in Clark County, Nevada, and 5 sites in adjacent Mohave County, Arizona between 1060 and 3150 feet (320-960 meters) elevation. About 9 (17%) of the Nevada populations were presumed extirpated, most due to urban expansion in the west half of the species' range in Las Vegas Valley. Because of these severe and ongoing impacts it was placed on the list of category-2 candidates for listing under the Endangered Species Act, which require more information before a listing decision can be made. It was also placed on the Nevada list of critically endangered species. Aerial and ground surveys were conducted in southern Nevada during summer 1994 to relocate historical populations, discover any additional populations, and document their biology, ecology, and conservation status. Other recent surveys have also been conducted, primarily by BLM and NPS personnel. This report summarizes the results of all recent surveys, reviews all previous knowledge of the species, and recommends conservation and recovery actions designed to prevent it from becoming a threatened or endangered species.

We thank the numerous individuals who, over the years, gathered and/or made available most of the information on which this report is based, in particular Gayle Marrs-Smith, Teri Knight, Jim Holland, Jennifer Haley, Kimball T. Harper, Laura L. Hickerson, Art Phillips, Sheila Sheldon, Margaret Williams, and Ann Pinzl. Most of these people are listed in the Knowledgeable / interested individuals section at the end of this report, or are cited as specimen collectors in Table 6. We also thank all of the herbaria cited in Table 6, and their curators, for maintaining and making available the specimens in their care. A draft of this report benefitted greatly from reviews and comments contributed by Janet Bair, Glenn Clemmer, Jennifer Haley, Jim Holland, Teri Knight, Gayle Marrs-Smith, Pat Murphy, and Arnold Tiehm. None of these people should be held responsible for any of the opinions or judgments expressed herein, however, nor for any errors that may remain.

All information contained in this report was believed current and complete on the date it was printed. Please submit any and all additions, corrections, updates, comments, or suggestions, whatever their magnitude, to the Nevada Natural Heritage Program or the U.S. Fish and Wildlife Service at the above addresses, for consideration in future editions.

SUMMARY 1

ACKNOWLEDGMENTS 2

TABLE OF CONTENTS 3

I. CLASSIFICATION AND NOMENCLATURE 7

Scientific Name 7

Original Publication 7

Type Specimen 7

Synonym(s) 7

Vernacular Name(s) 7

Family 7

Major Groups 7

Review of Alternative Taxonomic Treatments 7

II. TAXON HISTORY 8

III. PRESENT LEGAL OR OTHER FORMAL STATUS 9

International 9

Federal 9

State 9

IV. DESCRIPTION 9

Non-technical 9

Technical 9

Field Characters 10

Photographs and Line Drawings 10

V. SIGNIFICANCE OF TAXON 10

Natural 10

Human 10

VI. GEOGRAPHIC DISTRIBUTION 11

Geographic Range 11

Precise Occurrences 11

Historical site(s) rediscovered or recently known extant 12

New site(s) discovered 12

Historical site(s) searched for but not rediscovered 13

Other site(s) searched where not discovered 13

Historical site(s) known or suspected to be erroneous reports 13

Historical site(s) known or assumed extirpated 13

Historical site(s) where present status unknown 14

Potential site(s) meriting future field surveys 14

Biogeography 14

Phylogeny 15

VII. HABITAT CHARACTERISTICS 16

Environment and Habitat Summary 16

Physical Characteristics 16

Physiography 16

Climate 17

Geology 17

Soils 17

Hydrology 18

Air and water quality requirements 18

Geomorphology 18

Aspect and slope 18

Biologic Characteristics 18

Community physiognomy 18

Vegetation type 18

Associated species 18

Other endangered, threatened, and sensitive species 19

Land Management 19

VIII. BIOLOGY AND ECOLOGY 21

Population Summary 21

Demography 21

Phenology 22

Genetics 22

Reproduction and Dispersal 22

Hybridization 24

Pathology 24

Predation 24

Competition 24

Response to Disturbance 24

Other Interactions 25

IX. EVIDENCE OF THREATS TO SURVIVAL 25

Present or threatened destruction, modification, or curtailment of habitat/range 25

Over-utilization for commercial, recreational, scientific, or educational purposes 27

Disease or Predation 27

Inadequacy of Existing Regulatory Mechanisms 27

Other Natural or Man-made Factors 28

X. GENERAL ASSESSMENT AND RECOMMENDATIONS 29

General Assessment 29

Status Recommendations 30

Critical Habitat Recommendations 31

Conservation and Recovery Recommendations 31

XI. INFORMATION SOURCES 33

Literature Cited 33

Map Sources 35

Field Research 36

Specimens 36

Knowledgeable/Interested Individuals 37

APPENDIX 1. TABLES.

Scientific Name: Arctomecon californica Torrey & Frémont in Frémont (1845).

Original Publication: Torrey, J. and J. C. Frémont. 1845. Descriptions of some new genera and species of plants, collected in Captain J. C. Frémont's exploring expedition to Oregon and north California, in the years 1843-1844, p. 312. In Frémont, J. C., Report of the exploring expedition to the Rocky Mountains in the year 1842, and to Oregon and north California in the years 1843-1844, p. 311-319. Washington DC: Blair & Rivers.

Type Specimen: NEVADA, Clark County: at "Las Vegas, near the Rio Virgen in Southern Utah - Lat. 36° 10'", "in the Californian mountains, on the banks of a creek", 3 May 1844, Frémont 429 (lectotype by Nelson and Welsh 1993, apparent holotype: NY). The NY specimen appears to represent the remains of the only specimen collected by Frémont, apparently rendering the lectotypification unnecessary.

Synonym(s): None.

Vernacular Name(s): Las Vegas bearpoppy; California bearpoppy; California bearclaw poppy; yellow bearpaw poppy; desert-poppy.

Family: Papaveraceae (poppy family).

Review of Alternative Taxonomic Treatments: Arctomecon californica has always been regarded as a well-defined and distinctive species, and no other taxonomic treatments have been proposed. The most recent taxonomic review of the genus Arctomecon can be found in Nelson and Welsh (1993). The lower Grand Canyon sites (AZ2-AZ5) of Arctomecon californica visited by Phillips (Phillips and Phillips 1988; Phillips in litt. 12 October 1994) appear to be distinctive in their limestone habitat and fruit and leaf morphology, suggesting the existence of an unnamed species or subspecies represented by these populations. Kimball T. Harper of Brigham Young University (in litt. 12 October 1995) has since documented that the genetic distance between one of these sites and the remainder of Arctomecon californica is comparable to that between other species in the genus, and is convinced that at least varietal status will have to be given to the Grand Canyon populations. This does not alter the validity of the remainder of Arctomecon californica.

1844: First collected by John Charles Frémont on 3 May at Las Vegas on his second expedition to explore the American West.
1845: Described by Torrey and Frémont in Frémont (1845).
1891: Next collected on 1 May in Las Vegas Valley by Coville and Funston during an expedition to the Death Valley region.
1906: Collected by J. Stirling in April, and labeled (apparently in error) from Searchlight, Nevada.
1917: First collected from north of Las Vegas and in the Muddy Mountains east of Las Vegas by Tidestrom and Brandegee.
1933-1941: Collected at many new sites, including the Lake Mead area, by Clokey, Grater, Maguire, McKelvey, Munz, Tanner, Train, and others.
1941: First collected in Arizona and in the lower Grand Canyon, northwest of Pierce Ferry, by J. Pinckney Hester in August.
1960-present: Collection and documentation of new sites resumes. Urban growth and site extirpation in Las Vegas Valley accelerates.
1974: Recollected from south side of lower Grand Canyon by Arthur Phillips.
1977: Janish (1977) raised concern about population losses in Las Vegas area.
1979: Listed as critically endangered by the State of Nevada under NRS 527.270 on 14 February.
1979: Status report by Holland (1979) recommended endangered status pending further surveys.
1979-present: Detailed biologic, ecologic, biochemical, and genetic studies on Arctomecon species conducted by Harper, Meyer, Nelson, Raynie, Sheldon, and others accelerated.
1980: Designated category-1 candidate for listing by USDI Fish & Wildlife Service (1980).
1983: Designated category-2 candidate for listing by USDI Fish & Wildlife Service (1983), where it has remained to present (USDI Fish & Wildlife Service 1993).
1988: Status survey by Phillips and Phillips (1988) recommended protective measures for Nevada sites.
1993: Taxonomic revision of Arctomecon by Nelson and Welsh (1993) concurred with previous treatments of Arctomecon californica, and recommended protection under the Endangered Species Act.
1993: Extensive new surveys conducted by Bureau of Land Management on BLM lands (Marrs-Smith 1995).
1994: Sites in lower Grand Canyon resurveyed by Arthur Phillips III on 28-29 April. Field surveys conducted by Rancho Santa Ana Botanic Garden for this report.
1994: U.S. Fish and Wildlife Service conducted status review meeting for Arctomecon californica on 18 October in Las Vegas. Lower Grand Canyon sites first suspected of being a distinct taxon.
1995: Draft Habitat Management Plan completed by Marrs-Smith (1995) for BLM lands, recommending establishment of four Areas of Critical Environmental Concern.
1995: Studies of the genetics, pollination, and seed biology of Arctomecon californica were funded through the multiple species component of the Clark County Long-Term Desert Conservation Plan.

International: The Nature Conservancy (TNC) ranks sensitive taxa at state, national, and global levels on a scale of 1 to 5, 1 being the most vulnerable and 5 the most secure. Arctomecon californica was most recently ranked 2 by TNC at all levels (Morefield and Knight 1992). The results of this report show 3 to be the more appropriate rank at all levels.

Federal: Arctomecon californica was most recently designated a category-2 candidate for listing as endangered or threatened under 16 U.S.C. 1531 et seq., the Endangered Species Act as amended in 1988 (USDI Fish and Wildlife Service 1993, p. 51148). Category-2 includes taxa for which "proposing to list as threatened or endangered is possibly appropriate, but for which sufficient data on biological vulnerability and threats are not currently available to support proposed rules" (USDI Fish and Wildlife Service 1993, p. 51145). This report recommends a change to category-1 candidate status.

State: Nevada: Arctomecon californica is listed as critically endangered under Nevada Revised Statutes (NRS 527.270). Critically endangered taxa are those "threatened with extinction," whose "existence is endangered," and whose "survival requires assistance because of over exploitation, disease or other factors or because its habitat is threatened with destruction, drastic modification or severe curtailment" (NRS 527.270). It is also on the Northern Nevada Native Plant Society's Threatened list (Morefield and Knight 1992). Arizona: no legal status or formal protection.

Non-technical: Arctomecon californica is an 8-24 inch high perennial herb, with stout taproot, rather numerous grayish-blue basal leaves, and large bright-yellow flowers; leaf blades are wedge-shaped, broadest above the middle, shallowly 3-5-toothed at the tip, up to 6 inches long and 1 inch wide, covered with long white, shaggy hairs, narrowed at the base to a stalk about as long as the blade; flowers (late March to late May) several to many on one to several leafless stems, petals usually 6 (sometimes 4 up to 8), yellow, 1-2 inches long; stamens numerous; sepals 2 or 3, hairless, falling soon after the flowers open; fruit (May to June) forming as egg-shaped capsules up to 1 inch long, upright, 6-ribbed, opening at the top by flaps that develop as the fruit dries; seeds usually at least 100 (up to 160) per fruit, shiny black.

Technical: Plants erect or forming rounded clumps, subscapose, 2-6 dm tall, from a branching caudex, this clothed with ash- to straw-colored marcescent leaf bases; basal leaves 5-14 cm long, 3-25 mm wide, cuneate, grayish-blue, usually with 3-5 apical teeth each with an acerose bristle 4-10(12) mm long, hirtellous as well as moderately long pilose with barbellate trichomes to ca. 10 mm long; stems sparsely pilose and scabrous, glabrous above; inflorescence of paniculiform cymes, 5-20 flowered (late March to late May), 10-30 cm long with 1-2 foliose bracts, these long pilose; pedicels 7-17 cm long; sepals 2 or 3, 8-15 mm long, glabrous or sparingly pilose; petals (4)6(8), yellow, 1.5-3.2 cm long, slightly longer than wide; stamens equaling or slightly exceeding the stigma; anthers 2-3 mm long, the filaments filiform; carpels 4 or 5, astylose; fruit (May-June) forming capsules, ovoid to obconic, 12-23 mm long, 7-10 mm wide, acrocidal along 4 or 5 sutures, splitting not more than 1/4 their length; seeds shiny black, 2.5-3 mm long, ca. 1.2 mm thick, conspicuously arilate, usually at least 100(160). (Descriptions modified from Nelson and Welsh 1993.)

Field Characters: Arctomecon californica is easily distinguished by its fuzzy grayish-blue basal rosette of leaves, the tall flowering and fruiting stems with large yellow flowers, and fruits opening at the apex revealing numerous small dark seeds. The species is very different from associated plants and is easily noticed. The three species of Arctomecon share ample characters to readily demonstrate their affinity, while the differences between the species are substantial enough to provide clear taxonomic units. All three species are readily recognized by their foliage; the dense rosettes of relatively long, broad leaves appear to be very "extravagant" in comparison to that of most of the plants of the Mojave Desert region.

The species of Arctomecon differ from each other morphologically by the arrangement of flowers in the inflorescence, flower color, status of the petals following anthesis, number of locules per ovary, outline of the distal margins of the leaf, amount and kind of foliar vestiture, and the overall height of the plant. The strong morphologic differences, when considered with the geographic isolation of the species from each other, suggest that the separation of the taxa was not a recent event (Nelson and Welsh 1993).

Photographs and Line Drawings: Line drawings are published in Janish (1977), Frémont (1845, 1887), and Nelson and Welsh (1993). See Appendix 2, Figure 1, for reproduction of Janish's (1977) drawing, and figures 4-30 for recent photographs taken for this report and filed with the Nevada Natural Heritage Program.

Natural: This species is endemic to gypsic soils. It grows on desert pavement and gravelly slopes which are otherwise sparsely vegetated, and thus probably aids in soil retention. The species blooms later than most of its associates and serves as a valuable source of pollen and nectar for insects as the desert gets hotter and drier.

Human: This is one the most spectacular members of the Arizona and Nevada floras. It has a striking appearance both when it is flowering and in the vegetative state and is well worthy of cultivation. It is one of the few species that seems to demonstrate a tolerance for gypsic soils, and may prove valuable in the re-vegetation of disturbed gypsic soils of arid lands, or in the development of crop varieties that tolerate such soils. The latex in the stems of many members of the poppy family, including Arctomecon (Raynie et al. 1991), contains biologically active alkaloids which may have medicinal applications. Alkaloids known to be present within other genera of the poppy family include; morphine, codeine, thebaine, papaverine and narcotine (Rizk 1986). Species within genera such as Argemone, Corydalis, Dicentra and Eschscholzia, were used for medicinal purposes by Native Americans. Analgesic, emetic, dermatologic, disinfectant, gastrointestinal and hallucinogenic uses are documented (Duke 1985; Moerman 1986). The species is interesting historically because it is one of the few species described as a result of Captain John Charles Frémont's second expedition into western America.

Geographic Range: (Appendix 1, Tables 1-3; Appendix 2, figures 32-33; Appendix 3 maps). Globally and historically, Arctomecon californica has been documented from 108 populations at 95 sites in east-central Clark County, Nevada, and from eight sites in the Lake Mead and lower Grand Canyon areas of northwestern Mohave County, Arizona. These sites are managed by the Bureau of Land Management, National Park Service, State of Nevada, Department of Defense (Nellis AFB), Hualapai Indian Reservation, and private individuals. The species' distribution ranges from south of the Temple Bar area of Lake Mead to near the southern base of the Virgin Mountains (36° 00'N to 36° 30'N latitude), and from lower Grand Canyon to Las Vegas Valley (113° 53'W to 115° 15'W longitude). In Nevada, 91 populations at 78 sites have been documented recently enough to be presumed extant, as have all eight sites in Arizona.

Precise Occurrences: Site numbers and descriptions are given in Appendix 1, Tables 1-3, along with their equivalent Nevada Natural Heritage Program element occurrence numbers. The tables cross-reference each site to its related maps and figures, as well as its most recent year observed and source(s) of documentation. The tables also show estimated areas and numbers of plants for each site, along with elevations, apparent land management status, and types of impacts or threats. Nevada element occurrence (="population") numbers have been updated to reflect incorporation of all sites documented in this report into the Nevada Natural Heritage Program database. Historical (pre-1994) occurrence numbers in Table 2 are shown crossed out where they were combined into a single occurrence; these numbers were re-used for new occurrences elsewhere in the tables.

The occurrences documented for this report were derived from a variety of sources employing different survey methods and levels of precision, and varying precision is therefore reflected on the maps in Appendix 3. Small sites of uncertain precision are shown as solid triangles on the maps. Large sites (14, AZ1, AZ6-8) with uncertain boundaries are shown as hachures without enclosing boundary lines; survey methods for these sites likely over-estimated areas and under-estimated numbers of plants, and are discussed further under the appropriate sections below. Some sites shown with boundaries within the Lake Mead National Recreation Area, and derived from National Park Service records, may likewise be generalized and encompass unoccupied as well as occupied habitat. All other sites shown as solid circles, or as hachured areas with boundaries, are considered precise indications of occupied habitat within the limits of the map scales used.

To the best of our knowledge, no privately managed sites were entered upon to obtain any of the new information documented by our surveys without the consent of the owners or managers. In many cases, private sites were small and easily viewed and documented from adjacent public access areas. In a few cases, sites were not surveyed due to lack of access, and our information is then based solely on previously existing reports.

Biogeography: The gypsic substrates that define the habitat of Arctomecon californica in southeastern Nevada support a unique edaphic vegetation association, known as the gypsum barren community (Knight 1983), surrounded by the creosote bush, saltbush, and blackbrush zones that characterize the low to mid-elevation Mojave desert of this part of the state. Arctomecon californica is a conspicuous member of this association. Arctomecon represents one of several radiations (or in situ adaptations) in the poppy family associated with increasing aridity in southwestern North America. All of the putatively closely related genera are either restricted to western North America (Romneya, Canbya, Platystemon, and Meconella) or apparently have their origins there (Argemone). In addition these genera are either primarily coastal or hot desert or both. This strongly suggests that the origin of Arctomecon should be sought in western North America. Although inferring historical ranges and distributions of ancestral species from present species distributions is questionable, it is still most likely that the geographic origins of Arctomecon are within, or very close to, the current range of the genus (Appendix 2, Figure 32). This is because no other Papaveraceous genera potentially related to Arctomecon are associated with gypsic soils, while all three Arctomecon species are (Nelson & Welsh 1993). The simplest explanation for the gypsophily of all Arctomecon species is that their common ancestor was also a gypsophile rather than, for example, that all three species adapted independently to gypsic soils. Given that gypsic soils are not continuous, and that the extant species have not displayed great dispersal ability, it also seems unlikely that the ancestor of this genus could have migrated great distances on gypsic substrates. The conclusion then is that the lineage giving rise to Arctomecon has been limited to the region centered around what is now southern Nevada, and has never been particularly more widespread in the southwestern United States.

Phylogeny: In spite of the medicinal importance of the poppy family, basic research into the phylogenetic relationships of the family (and the resulting interpretation of biogeographic data) has been slow in coming. Very recently, Kadereit et al. (1994) investigated phylogenetic inferences in Papaveraceae, based on morphologic data. In this "parsimony" based analysis, data supported the hypothesized relationship depicted in Figure 31 (Appendix 2). Arctomecon was one of a series of genera included in a monophyletic, narrowly defined Papaveraceae (including Papaver, Roemeria, Stylomecon, Meconopsis, Romneya, Arctomecon, and Argemone). Unfortunately, there was no unambiguous inference as to what genus (or genera) shared most recent common ancestry with Arctomecon. In some of the most parsimonious trees it was placed as the closest extant relative of Argemone. In other most parsimonious trees it was placed as the sister-lineage to Papaver, Roemeria, Stylomecon, Meconopsis, and Romneya.

Additional insight has been provided by restriction fragment analysis of three regions of the chloroplast genome (Kadereit et al. in prep., pers. comm. 1995). The phylogenetic inferences based on these molecular data differed somewhat from those based on morphology (Figure 31). The molecular data supported the hypothesis that the most recent ancestor of Arctomecon is shared with prickly poppies (Argemone). This relationship was also found in some, but not all, of the "most parsimonious" trees based on morphology. The chloroplast data also suggested Arctomecon and Argemone together share common ancestry with Romneya.

If we assume that Arctomecon is most closely related to Argemone, and together these two are most closely related to Romneya, then we can also make some inferences regarding characters that might be used for detecting relationships within Arctomecon. For example, the pale cream-colored petals, shared by Arctomecon humilis and A. merriamii are also found in Argemone and Romneya. This means that this corolla feature does not provide evidence that Arctomecon humilis and A. merriamii are most closely related, because it is a shared ancestral character. Indeed, most of the characters shared by any two species of Arctomecon are shared ancestral characters. As a result, there is no overwhelming evidence indicating which two species share most recent common ancestry (are most closely related). The only possible morphologic characteristics that might provide some evidence of relationships is the dense, barbellate trichomes found in Arctomecon californica and A. merriamii (these are absent in A. humilis, Argemone and Romneya). This character might be used as evidence to suggest that 1) Arctomecon humilis became isolated from the remainder of Arctomecon before the time that A. californica and A. merriamii became separate species; and 2) both Arctomecon californica and A. merriamii represent relatively recently derived species. This hypothesis is also supported by recent a genetic study (Kimball T. Harper in litt. 12 October 1995) which showed that Arctomecon californica and A. merriamii are slightly more similar to each other genetically than either species is to A. humilis.

Also of note is that Arctomecon and Argemone, by virtue of sharing a recent common ancestor, are of equal age. This indicates that Arctomecon (as a lineage), with 3 surviving, geographically restricted species, has been far less "successful," in terms of speciation rate and dispersal, than Argemone, which has about 30 species found in North and South America and Hawaii.

Environment and Habitat Summary: (Appendix 2, figures 10-30) Excluding the undescribed taxon in the lower Grand Canyon, Arctomecon californica appears restricted to soils with high gypsum contents, measured between 36% and 69% at some sites (Meyer 1987). A report from soil of volcanic origin in Valley of Fire State Park (site 11) has not been verified. The often spongy, finely textured, and crusted gypsic soils form relatively barren, low-competition sites within creosote bush, saltbush, and blackbrush associations more typical of the Mojave Desert. The sites are hot and dry except for low and variable incident precipitation, exhibit all aspects and slopes, generally occur in areas of low relief, but often show hummocked, dissected, or badland microtopography. Elevations range from 1221-3150 feet (372-960 meters). The vegetation on Arctomecon californica sites consists of sparse, mostly herbaceous associations of other gypsum-tolerant species, characteristically including Ephedra torreyana, Lepidium fremontii, Petalonyx parryi, Psorothamnus fremontii, Anulocaulis leiosolenus, Enceliopsis argophylla, Mentzelia pterosperma, Tiquilia latior, Eriogonum insigne, Phacelia palmeri, P. pulchella, and Psathyrotes pilifera. (Appendix 1, Table 4). Heavy cryptogamic crust cover is also present at many sites.

Land Management: (Appendix 1, Tables 1-3) For all sites, management status was determined based on the best maps and other information available to us, but generally was not further verified. Ownership status of associated minerals and water rights was not determined for any site, nor was the presence or absence of any easements or other encumbrances.

The range of Arctomecon californica spans private, public, and Native American tribal lands. Public lands within the range of the species are managed by several agencies, including the Bureau of Land Management, the National Park Service (Grand Canyon National Park and the Lake Mead National Recreation Area), Nellis Air Force Base, and the State of Nevada. The easternmost occurrences of the undescribed variant in the Grand Canyon are on the Hualapai Indian Reservation. The proportions of the species' total remaining population and of extirpated sites represented within each of these land management jurisdictions are shown in Appendix 2, figures 2-3, and are summarized in the following table:

Global population by:	NPS	BLM	Nevada	Private	Nellis AFB	Hualapai
Plants	> 54.7%	32.7%	5.8%	4.4%	2.4%	> 0.0%
Area	< 77.2%	17.7%	2.5%	1.9%	0.7%	> 0.0%
Sites:	> 18.5%	45.2%	6.4%	27.9%	0.3%	1.8%
Unimpacted	> 13.3%	31.6%	1.3%	---	---	1.8%
Impacted*	> 5.2%	13.6%	3.3%	4.7%	0.3%	---
Extirpated*	---	---	1.8%	23.1%	---	---

Population Summary: Based on the information gathered for this report, the total known remaining global population of Arctomecon californica was estimated to be at least 831,861 plants, and to occupy at most 39,266 acres of habitat divided among 99 populations in east-central Clark County, Nevada, and adjacent northwestern Mohave County, Arizona, between 1221 and 3150 feet (372-960 meters) elevation. Local authorities and knowledgeable sources indicate that 1994 was a very good year for the species in terms of the geographic extent of populations, the number of plants represented in populations, and the vigor of individuals. The estimates noted above may therefore represent a peak in the cyclic population fluctuations described below. Based on the probable extent of unsurveyed potential habitat remaining in southern Nevada and northwestern Arizona, we estimate that the true total population for Arctomecon californica is at most 25% greater than that estimated above.

Demography: Sheldon (1994) divided Arctomecon californica populations into six age classes based on rosette size. Flowering was observed in all but the first two age classes (seedling and juvenile, one-year-old). Overall survivorship of the plants at her study sites was low, ranging from 14% (Stewart Point, site 14) to 38% (Temple Bar, site AZ1). Mortality varied inversely with size; the non-reproductive age classes (seedlings and juveniles) experienced the highest mortality. The seedling stage has been found critical in the structure of populations and is often the most vulnerable phase in the growth of the individual (Cook 1979). Loss of reproductive potential was highest at the bud and fruit stages.

During surveys by Rancho Santa Ana Botanic Garden in 1994, a subsample of plants in some populations was divided into two classes based on phenology (flowering : non-flowering). The ratio between these classes varied widely, from 1:20 to 10:1, although ratios in the range 2:1 to 1:1 were more common. Plant densities also varied widely. From estimates of the total plants within total occupied habitat (see population summary, above), an average density of 21 plants per acre can be calculated. However, densities ranged from 750 plants per acre (site 12, Appendix 1, Table 3) to 1 plant per acre (site 32, Appendix 1, Table 2).

Meyer's (1987) studies of Arctomecon californica demonstrated drastic year to year fluctuations in population density. Data suggest that such volatile cycles are primarily the result of a relatively short life span (individuals surviving the first year may be expected to live an average of 4-5 years) coupled with irregular occurrence of germination events. Meyer found that years with sufficient winter rainfall to assure significant establishment of the seedlings may occur up to nine years apart. Hence the species appears to rely on high reproductive output and the maintenance of a large reservoir of long lived seed in the soil in order to persist (see Reproduction and Dispersal below).

Phenology: Arctomecon californica has been observed flowering from late March to late May. Fruits mature and dehisce usually before the end of June. During the hot summer months the flowering axis senesces. The plants recover in late fall, producing many hairy basal leaves. The differences in basal rosette morphology between individual plants seems to be related to their reproductive output. Plants with smaller-diameter rosettes appear to have lower reproductive output than those with larger-diameter rosettes (Meyer 1979).

Genetics: A recent study conducted at Brigham Young University (Van Buren and Harper 1995; Kimball T. Harper in litt. 12 October 1995) found that, although the average genetic similarity among Arctomecon californica populations (excluding the lower Grand Canyon sites) was relatively high (94%), the majority of 17 populations studied contained genetic markers that were unique or unusual (found in 2 or fewer other populations). These included populations at North Las Vegas Airport (site 26), Water Authority yard (site 31), PABCO Mine road (site 2), Big Gypsum Ledges (site AZ1), and populations in the Gold Butte and Rainbow Gardens areas. The importance of these rare genotypes to the long-term survival of the species is unknown but potentially significant, and their conservation is therefore critical.

Reproduction and Dispersal: Pollen exclusion studies by Sheldon (1994) indicated that Arctomecon californica was primarily an outcrossing species, although a small percentage of seed produced by self pollination was noted. Insects noted as potential pollen vectors included species in the orders Hymenoptera (67%), Coleoptera (25%) and Lepidoptera (8%; percentages were of total insects collected on plants during the study period).

Preliminary results from pollinator and breeding system studies conducted by Laura L. Hickerson (pers. comm., 16 January 1996), Vincent J. Tepedino, T. Griswold, and M. Duff of the USDA - ARS Bee Lab at Utah State University were similar to the above. Xenogamy (crossing between different plants) was the primary reproductive mode, producing up to about 160 seeds per capsule, while no more than 12 seeds were produced by autogamy (fertilization within a single flower). Stigma receptivity lasted at least two days. Hand pollination produced significantly higher seed sets than natural pollination, suggesting that Arctomecon californica populations are not saturated by their existing pollinator populations. Furthermore, compared with a large, relatively pristine population in Lake Mead NRA, a small and fragmented population of Arctomecon californica in Las Vegas Valley (Water Authority yard, site 31) showed significantly lower seed set by natural pollination, suggesting that the pollinator population there had become even less effective.

Arctomecon californica produces numerous blossoms, but frequently no more than half of its fruits develop and at least half of its seed abort (Sheldon 1994; personal observations). Based on the foregoing, it appears possible that some of these reductions are related to human and/or other impacts to pollinator populations, including fragmentation of the plant populations on which they depend. Insect herbivory and spontaneous tissue abortion at the fruiting stage also appears to play a role (Sheldon 1994). It may be possible for Arctomecon californica to withstand even substantial losses of reproductive potential without long-term impact to its soil seed bank; some such losses probably are natural and normal. Significant impacts to pollinator effectiveness, however, have the potential to push these losses beyond the sustainable limit.

Hickerson et al. identified 10 insect species apparently pollinating Arctomecon californica flowers. Nine of these occurred among nine study sites in Lake Mead NRA, and five were found among four sites in Las Vegas Valley. Of the five solitary bee species identified, four (Perdita meconis, P. robustula, Megandrena enceliae, and Synhalonia quadracincta) were restricted to the Lake Mead NRA sites, and one (Exomalopsis deserticola) was restricted to a Las Vegas Valley site (North Las Vegas Airport, site 26). Four species were common to both areas: three generalist social bees (Apis melifera, Lassioglossum sisymbrii, and Lassioglossum sp.) and one melyrid beetle (Trichochroides?). One buprestid beetle (Schizopus sp.) was found only at the Lake Mead NRA sites.

The 100 or more seeds usually found in mature fruits represent a relatively high reproductive output, especially for a perennial plant. The species appears to rely on a large, long lived seed bank in order to achieve local persistence in its island-like habitats (S. Meyer, in prep., as cited in Sheldon 1994). The short-lived perennial habit with its emphasis on fecundity probably is a more successful combination in the open vegetation on gypsum and other arid badlands soils than in the surrounding, more closed creosote bush, saltbush, and blackbrush associations. Sheldon (1994) found that gravity, aided by wind propulsion of the seeds and fruiting stems, appeared to be the primary seed dispersal agent for Arctomecon californica. The strongly arilate seeds suggest that ants could also play an important role in seed dispersal, and this is supported by limited field observations as well (Laura Hickerson, pers. comm. 16 January 1996). In any case, the seeds probably do not disperse farther than several feet in any one generation, strongly limiting the species' ability to colonize isolated or fragmented habitats.

Separation by flotation of organic material from the soil collected near the plants revealed a large quantity of seed "entrapped" within cryptogamic soil crusts. This emphasizes the importance of protecting these soil surfaces in order to maintain seed banks, and possibly to enhance soil moisture and nutrient retention and the establishment of seedlings after germination (Sheldon 1994). Cryptogamic crusts are known to increase soil nutrient levels at the surface (Harper and Pendleton 1993), which may substantially aid seed germination on otherwise nutrient-poor soils such as gypsum. Further studies of the seed biology of Arctomecon californica are currently under way.

Hybridization: None reported, observed, or suspected.

Pathology: Insect larvae were observed in the stems of many individuals in the lower Grand Canyon populations in 1988 (Phillips and Phillips 1988). This infestation was not apparent on a subsequent visit to these sites in 1994 (Phillips, pers. comm. 1994). Insect infestation or disease has not been noted as a major cause of mortality in other populations. Insect damage noted seems to have detrimental effect only after seeds are set. Larvae bore into stems, killing individual rosettes and often entire plants. This prevents rosettes from offsetting but does not affect seed production or maturation.

During surveys of populations on lands of the Bureau of Land Management, Gayle Marrs-Smith (personal communication, 9 January 1996) and Sheila Sheldon noted a patchy, dark blue fungus (probably a rust) on the leaves of many flowering and vegetative plants, particularly in the Gold Butte and Overton areas. They did not report any negative impacts on reproductive success resulting from this infestation. Its identity, origin, rate of spread, and long-term effects are unknown at present, however, and merit further investigation.

Predation: Minor herbivory by rabbits has been noted (Sheldon 1994). The lack of significant herbivory by associated vertebrate species may be related to the diverse alkaloid chemistry possessed by members of the genus (Raynie et al. 1991).

Competition: Arctomecon californica is found only in the open, low-density plant associations characteristic of gypsic substrates, and thus occurs where competition for light and moisture are minimal. Competition for nutrients may be more significant, even at low plant densities, because of the extreme nutrient unavailability typical of gysic soils. Frequently Arctomecon californica is the dominant species on a site, but population densities are usually low enough that intraspecific competition may be significant only at the seedling stage. The species' preference for low-competition conditions may be a secondary effect of its dependence on gypsic soils, since it has never been found in low-competition situations on other soil types.

Response to Disturbance: At several sites, Arctomecon californica has been observed to colonize and reproduce on recent disturbances such as roadsides and cleared lots. We have observed this to be true of many, if not most, rare plant species in the arid west, and this is often interpreted by some to suggest that the species in question is not threatened by habitat disturbance, but instead is able to survive or even thrive with continual disturbance. This usually results from a misunderstanding of plant ecologic responses based on short-term observation.

Most rare plant species are rare because they are adapted to and depend upon rare habitat types. Many of these habitat types impose harsh growing conditions that exclude most other plant species, thus creating relatively low-competition conditions for the few remaining species that are able to adapt. Disturbance also creates a temporary low-competition situation of which rare species, already adapted to such conditions, frequently are able to take short-term, opportunistic advantage. Almost always, though, this is observed only if the disturbance occurs within or immediately adjacent to a source population occupying the rare soil or other habitat type that the species requires for long-term survival, and only when the disturbance is temporary and has begun to stabilize. Almost never has a rare plant species been observed continuing to spread onto disturbances farther outside its rare habitat type, or persisting where disturbance is severe and continuous. If rare species had the biologic and ecologic characteristics of invasive weeds, they would not now be rare. No plant population can withstand severe, uninterrupted disturbance of its habitat, and rare plants are no exception.

Thus, while Arctomecon californica may be seen thriving for a few generations on disturbed sites, all our observations indicate that its long-term survival depends upon the continued availability of undisturbed or recovering soils with high gypsum contents. Arctomecon californica has never been observed spreading off of these soils, and permanent losses of populations have been documented where disturbance has been continuous and severe.

Other Interactions: None noted.

Causes of extirpation, and impacts and threats observed or reported for the remaining extant sites, are summarized in Appendix 1, Tables 1-3.

Over-utilization for Commercial, Recreational, Scientific, or Educational Purposes: Due to the spectacular appearance of the plant in flower and in the vegetative state, Arctomecon californica attracts much admiration and attention from desert visitors and residents. Plants are collected for cultivation. With the increasing cost of water in the southwestern U.S., many home owners are attempting to landscape with native, drought-tolerant species. Removal of plants for landscape purposes in the desert communities, though technically illegal without a permit, constitutes a significant threat to the species. Past efforts to transplant individuals during mitigation programs have uniformly failed. Seed germination efforts have been mostly unsuccessful. Until successful cultivation methods can be developed, attempts to propagate the species outside its native habitat will only continue to harm natural populations. The existence of a population on private lands in Washington County, Utah, apparently introduced from seed, holds promise for this form of propagation and should be investigated further.

Arctomecon californica is also attractive to scientific collectors who have, over the years, documented many populations by collecting specimens for deposit in museums and herbaria (see Appendix 1, Table 6). Except in a few cases where specimens were collected immediately prior to the anticipated extirpation of sites from other causes, scientific collecting is neither known nor likely to have had significant impacts on any population of the species.

Disease or Predation: No significant short-term threats noted (see above under Biology and Ecology). As noted above, the identity, origin, rate of spread, and long-term effects of a dark blue leaf fungus observed in several populations are unknown at present and merit further investigation.

Inadequacy of Existing Regulatory Mechanisms: Unless it is listed as endangered or threatened (50 CFR 17.61, 17.71) and occurs within federal jurisdiction, a plant has no formal protection under the federal Endangered Species Act (ESA), except for regulatory determinations by some federal land management agencies (i.e., BLM) that candidate species will be managed in order to avoid the need for listing. No federal protection currently extends to plants under non-federal jurisdiction unless they are listed as endangered and removing, cutting, digging up, damaging, or destroying them would be "in knowing violation of any law or regulation of any state or . . . of a state criminal trespass law" [ESA Sect. 9(a)2(B)], and that law extended to non-federal jurisdictions. It should also be noted that the Endangered Species Act and the various agency regulations implementing it are in direct conflict with provisions of the mining law of 1872 (30 U.S.C. 21 et seq.), and are therefore of uncertain protective value when mineral-related projects are involved.

Unless the status recommendations in this report are implemented, a recent decision by the USDI Fish and Wildlife Service to eliminate candidate status for all former category-2 candidate species will have an as yet unknown but potentially detrimental effect on conservation efforts for this species, depending on how other federal and non-federal agencies interpret and implement this change. Potentially this could accelerate the need to list Arctomecon californica as threatened or endangered.

USDI Bureau of Land Management policy provides that the agency "shall carry out management, consistent with the principles of multiple use, for the conservation of candidate species and their habitats and shall ensure that actions authorized, funded, or carried out do not contribute to the need to list any of these species as Threatened or Endangered." If a candidate species occurs entirely on federal lands, BLM policy further requires that it be included as a priority species in land use plans, and that range-wide or site-specific management plans be prepared "that identify specific habitat and population management objectives designed for recovery, as well as the management strategies necessary to meet those objectives" (BLM Manual Section 6840). A draft Habitat Management Plan for Arctomecon californica has been completed by the Las Vegas District of BLM (Marrs-Smith 1995). If implemented, this plan would provide significant new protective measures for several populations by, among other things, creating four Areas of Critical Environmental Concern. Effectiveness of these measures would still depend upon adequate implementation and enforcement resources, however.

Arctomecon californica is listed as "critically endangered" under Nevada Revised Statutes (NRS) 527.270. Such listing provides that " . . . no member of its kind may be removed or destroyed at any time by any means except under special permit issued by the state forester firewarden" on any lands in Nevada. The adequacy of this law, however, depends on informed and cooperative land managers, or on some form of deterrent enforcement, for which the current law does not provide. It also depends on the state forester firewarden's discretion in issuing or withholding permits, and in placing protective conditions on permits that are issued. Nevada law does not mandate the continued survival of any plant species which it declares to be in danger of extinction.

Although Arctomecon californica is protected under Nevada State law, the high number of recent extirpations and impacts suggests that, in many cases, the law may not have been enforced, at least in a proactive or deterrent manner. So far, the law has proven ineffective in preventing the destruction of this species and its habitat on privately managed lands, and the degradation of populations and habitat noted at many sites on BLM lands. Adequacy of this regulatory mechanism will require a much greater awareness of and involvement by the Nevada state agencies responsible for its administration and enforcement, as well as by the individuals and agencies responsible for compliance. The species is not protected by law in Arizona. However, management by the National Park Service, inaccessibility of the habitat, and lack of resource conflicts has so far provided protection for these populations.

Other Natural or Man-made Factors: Because Arctomecon californica is primarily an outcrossing species (see above), the presence of adequate numbers of pollinators is essential to successful reproduction. Recent studies have provided preliminary evidence that the effectiveness of pollinator populations in Las Vegas Valley has been significantly reduced over those in more pristine areas in Lake Mead NRA (Laura Hickerson, pers. comm. 16 January 1996; see above), possibly due to fragmentation of the plant populations on which they depend, or to other direct or indirect impacts of urbanization. These studies also showed significantly improved seed set with artificial hand-pollination in both areas, raising the possibility that all pollinator populations have been impacted to some degree. Ongoing declines in pollinator effectiveness could potentially result in reproductive failure and rapid extinction of Arctomecon californica.

General Assessment: As now known, the global population of Arctomecon californica consists of at least 830,000 plants restricted to less than 39,500 acres of publicly and privately owned land divided among 99 populations, 91 in east-central Clark County, Nevada, and eight in adjacent northwestern Mohave County, Arizona. Although an undescribed variant or species heretofore included in Arctomecon californica appears to exist in four of these populations on limestone in the lower Grand Canyon, the validity or distinctness of the remainder of Arctomecon californica as a species is not in question. The species is restricted to dry soils with high gypsum content, and is dependent entirely on incident precipitation, which results in wide yearly population fluctuations mirroring fluctuations in regional rainfall patterns. Most of the potential habitat of the species is now believed to have been surveyed, and it is estimated that the true total population is no more than 25% larger than that now documented.

The degree of impacts and short-term threats to Arctomecon californica vary widely across the range of the species, roughly along an east-west gradient, from virtually none in the Grand Canyon area to extreme in Las Vegas Valley. Populations and habitat within the Grand Canyon National Park and LMNRA appear to be largely secure. Populations and habitat on BLM land are currently at risk. Proposed management changes (Marrs-Smith 1995), if adopted and implemented, will significantly reduce or eliminate threats to the majority of sites on BLM land by placing them within Areas of Critical Environmental Concern (ACECs). In Las Vegas Valley, where most occurrences are on private land and subject to urban development, 13 populations have already been lost, the probability of extirpation in the near future is high for 17 others. There is little doubt that the current representation of the species in Las Vegas Valley is a small fraction of its historical representation. Recent genetic studies have shown that, although most populations are relatively similar (average genetic similarity 94%; Van Buren and Harper 1995), many contain rare or unique genotypes, suggesting that many such genotypes have been lost in Las Vegas Valley, with unknown consequences to the long-term survival of the species. Genotypes which might confer survival advantages under future conditions, such as climate changes or increased levels of air pollutants or ultraviolet radiation, may now or soon be lost. There is also recent evidence that pollinator effectiveness may have been impacted, particularly in Las Vegas Valley. If a long-term downward trend in pollinator effectiveness occurs, Arctomecon californica could eventually experience reproductive failure and subsequent rapid extinction.

At present, the remaining populations in Las Vegas Valley represent a small fraction of the total extant populations. The possibility of recovery activities within Las Vegas Valley has largely been precluded by conversion of habitat to urban uses. In addition, most of the remnants, because they are small and surrounded by urban environments, are not defensible, and are unsuitable as permanent preserves. Three possible exceptions are noted below. Protection of defensible sites within Las Vegas Valley is the highest conservation priority for the species. Extinction of the species appears highly unlikely in the short term under present circumstances, but a significant portion of the species has already been irretrievably lost, and few effective long-term measures are in place to prevent further losses. Many of the remaining populations are impacted or threatened by urban development, associated utility and highway development, population pressures resulting in damage from off-road vehicle and other recreational uses, mineral exploration and development, trampling of habitat by feral horses and burros, and possibly by impacts to insect pollinators. Threats from all these sources will exist indefinitely under present circumstances.

Status Recommendations: Las Vegas bearpoppy was most recently classified as a category-2 candidate for listing by the U.S. Fish and Wildlife Service, is listed as Critically Endangered by the State of Nevada, is considered globally vulnerable by The Nature Conservancy, is on the Threatened List of the Northern Nevada Native Plant Society, and is considered a Special Status Species by the Bureau of Land Management.

The best available evidence, as summarized in this report, is now sufficient to demonstrate that Arctomecon californica either meets the definition of an endangered species under the Endangered Species Act (ESA) of 1973 as amended, or soon will meet that definition. The ESA defines an endangered species as "any species which is in danger of extinction throughout all or a significant portion of its range" (other than insects declared to be pests), and a threatened species as "any species which is likely to become an endangered species within the foreseeable future throughout all or a significant portion of its range."

We therefore recommend that Arctomecon californica be classified as a category-1 candidate for listing under the ESA. Category 1 includes "taxa for which the [U.S. Fish and Wildlife] Service has on file enough substantial information on biological vulnerability and threat(s) to support proposals to list them as endangered or threatened species." We recommend deferring formal listing at this time, however, for the following reasons: 1) most of the losses and impacts so far documented are irreversible, and could not be mitigated by recovery actions; 2) large, relatively secure populations of the species still exist, appear stable at least for the short term, and would not now be made more secure by listing; and 3) conservation and recovery actions now underway, or recommended below, for the most vulnerable and defensible remaining populations provide the best chance for long-term viability of the species and, as long as they are being effectively pursued, could seriously be hindered by the regulatory and financial burdens a listing action would impose, and by the diversion of resources from existing actions the listing process would likely require. If and when it appears that other actions are becoming ineffective in avoiding further substantial and preventable losses or impacts to populations of the species, however, we recommend that formal listing then be pursued.

We also recommend that the Nature Conservancy's Global and Nevada ranks for Arctomecon californica be changed from 2 to 3, based on the size and number of relatively secure populations remaining. No other changes in status are recommended.

Critical Habitat Recommendations: None. If critical habitat were ever designated through the provisions of the Endangered Species Act, it should include all populations then known, and all soils with gypsum contents within the range of compositions known for all historical populations and within the historical range of the species, each surrounded by a minimum 50-meter wide habitat buffer. It is recommended that this critical habitat not be formally designated in cases where it might subject Arctomecon californica to increased threats to its survival.

Conservation and Recovery Recommendations: We offer the following recommendations as the best opportunities to maintain the genetic diversity and long-term viability of Arctomecon californica, to avoid the need to list it as threatened or endangered, and to reduce the overall long-term management costs for the species. They are listed in rough priority order, and all but the last two are considered essential to accomplish the foregoing goals. If monitoring (outlined in recommendation 7) indicates that these recommendations are not being implemented and/or are not effective in avoiding further preventable decline of the species, we recommend that the species be listed as threatened or endangered, and that more aggressive conservation and recovery measures be identified and pursued.

Map Sources:

U.S.G.S. 1:24,000 scale topographic series:

Apex, Nevada (1986 provisional edition)

Bitter Spring, Nevada (1983 provisional edition)

Bonelli Bay, Arizona (1983 provisional edition)

Boulder Canyon, Nevada-Arizona (1983 provisional edition)

Callville Bay, Nevada-Arizona (1983 provisional edition)

Columbine Falls, Arizona (1971)

Devils Throat, Nevada (1983 provisional edition)

Echo Bay, Nevada (1983 provisional edition)

Frenchman Mtn. Nevada (1983)

Gass Peak SW, Nevada (1983)

Gold Butte, Nevada (1984 provisional edition)

Government Wash, Nevada (1970)

Henderson, Nevada (1983)

Las Vegas NE, Nevada (1984)

Las Vegas NW, Nevada (1983)

Las Vegas SE, Nevada (1984)

Las Vegas SW, Nevada (1984)

Lime Wash, Nevada (1983 provisional edition)

Meadview North, Arizona-Nevada (1984 provisional edition)

Muddy Peak, Nevada (1983 provisional edition)

Overton Beach, Nevada (1983 provisional edition)

Tule Springs Park, Nevada (1983)

Valley of Fire East, Nevada (1984 provisional edition)

Valley, Nevada (1974)

Whitney Pocket, Nevada (1983 provisional edition)

U.S.G.S. 1:62,500 scale topographic series:

Hoover Dam, Nevada-Arizona (1953)

Virgin Basin, Nevada-Arizona (1953)

U.S.G.S. 1:100,000 scale topographic series:

Boulder City, Nevada-Arizona (1986)

Lake Mead, Nevada-Arizona (1986)

Las Vegas, Nevada-Arizona (1986)

BLM 1:100,000 Topographic Series, Surface Management Status:

Lake Mead, Nevada-Arizona (1979)

BLM 1:500,000 Topographic Series, Surface Management Status:

Nevada (State of) (1990).

Field Research: Field surveys were conducted on 19-22 April, 2-4 May, and 9-10 November, 1994, by Orlando Mistretta of the Rancho Santa Ana Botanic Garden, assisted by Tim Ross, Bart O'Brien, and Rob Ferber, to document the biology, ecology, and conservation status of historical and previously undocumented populations of Arctomecon californica in Nevada and Arizona. The results of these surveys are incorporated into this report, along with numerous recent surveys conducted by several other individuals and organizations, most notably the Bureau of Land Management's Las Vegas District office, the Lake Mead National Recreation Area, and Arthur Phillips III.

Specimens: All specimens known to document Arctomecon californica sites are listed by site in Appendix 1, Table 6. The list was compiled from all available published and unpublished sources, but is not necessarily exhaustive. Although new collections are discouraged, the Nevada Natural Heritage Program welcomes further additions or corrections to this table as they become known.

Janet Bair, Botanist
U.S. Fish and Wildlife Service
Nevada State Office
4600 Kietzke Lane, C-125
Reno, NV 89502
(702) 784 5227

Nancy Brian
National Biological Survey
Grand Canyon National Park
P.O Box 5614
Northern Arizona University
Flagstaff, AZ 86011
(602) 556 7463

Center for Plant Conservation
Missouri Botanical Garden
P.O. Box 299
St. Louis, MO 63166
(314) 577 5100

Kerry Christensen
Hualapai Indian Reservation
P.O. Box 300
Peach Springs, AZ 86434
(602) 769 2216

Jennifer Haley
Lake Mead National Recreation Area
601 Nevada Highway
Boulder City, NV 89005
(702) 293 8951

Kimball T. Harper
Department of Botany and Range Science
Brigham Young University
Provo, UT 54602
(801) 378 2192

Laura L. Hickerson
Department of Biology
USDA - ARS Bee Laboratory
Utah State University
Logan, UT 84322-5305
(801) 797 2526

Jim Holland
Lake Mead National Recreation Area
601 Nevada Highway
Boulder City, NV 89005
(702) 293 8986

Johnny Jones, Assistant Regional Forester/Resource Officer
Nevada Division of Forestry
4747 West Vegas Drive
Las Vegas, NV 89158
(702) 486 5123

Teri A. Knight
Director of Science and Stewardship
The Nature Conservancy
Nevada Field Office
1771 E. Flamingo, suite 111B
Las Vegas, NV 89119
(702) 737 8744

Gayle Marrs-Smith, Botanist
Bureau of Land Management
4765 West Vegas Drive
Las Vegas, NV 89108
(702) 647 5156

Mary Pat Matheson, Director
Red Butte Garden and Arboretum
University of Utah
Salt Lake City, UT 84108
(801) 581 5322

Randy McNatt
Bureau of Land Management
Nevada State Office
850 Harvard Way
Reno, NV 89502
(702) 785 6473

Susan E. Meyer
USDA Shrub Sciences Laboratory
Intermountain Research Station
735 North 500 East
Provo, UT 84606
(801) 625 5412

Orlando Mistretta
Rancho Santa Ana Botanic Garden
1500 N. College Ave.
Claremont, CA 91711
(909) 625 8767

Janet Monaco
Southern Nevada Water Authority
Department of Resources
1001 S. Valley View Blvd.
Las Vegas, NV 89153
(702) 258 3812

James D. Morefield, Botanist
Nevada Natural Heritage Program
Department of Conservation and Natural Resources
901 South Stewart Street, suite 5002
Carson City, NV 89701-5245
(702) 684 2902

Teresa Morgan
337 Hutchings Ln.
Henderson, NV 89014

Larry Morse, Chief Botanist
The Nature Conservancy
1815 N. Lynn Street
Arlington, VA 22209
(703) 841 5361

Patrick M. Murphy
Assistant State Forester, Resources
Nevada Division of Forestry
123 W. Nye Lane
Carson City, NV 89710
(702) 687 4350

Jan Nachlinger, Protection Planner
The Nature Conservancy
443 Marsh Avenue
Reno, NV 89509
(702) 322 4990

Deanna R. Nelson
Uinta and Wasatch-Cache National Forest
Heber City Ranger District
P.O. Box 190
Heber City, UT 84032
(801) 654 0470

Bruce Palmer
U.S. Fish and Wildlife Service
Arizona State Office
3616 West Thomas Rd, Suite 6
Phoenix, AZ 85019
(602) 640 2720

Arthur M. Phillips III
P.O. Box 201
Flagstaff, AZ 86002
(602) 779 2288

Ann Pinzl, Curator of Natural History
Nevada State Museum
600 North Carson Street
Capitol Complex
Carson City, NV 89710
(702) 687 4811

Douglas E. Raynie
Proctor & Gamble Company
Corporate Research Division
Miami Valley Laboratories
P.O. Box 398707
Cincinnati, OH 45239-8707

Sheila Sheldon
712 N. Jordan
Miles City, MT 59301
(406) 232 1470

Sid Slone, Supervisory Wildlife Biologist
Bureau of Land Management
4765 West Vegas Drive
Las Vegas, NV 89108
(702) 647 5156

Vincent J. Tepedino
Department of Biology
USDA - ARS Bee Laboratory
Utah State University
Logan, UT 84322-5305
(801) 797 2559

Arnold Tiehm
P.O. Box 21387
Reno, NV 89515
(702) 829 1645

Roy W. Trenoweth, State Forester
Nevada Division of Forestry
123 W. Nye Lane
Carson City, NV 89710
(702) 687 4350

Eric Watkins, Biologist
99ABW/EM
Environmental Management Directorate
4551 Devlin Dr.
Nellis Air Force Base, NV 89191-6546
(702) 652 3173

Margaret Williams, Executive Director
Northern Nevada Native Plant Society
4975 Malapi
Sparks, NV 89431
(702) 358 7759

Kim Zukosky
Southern Nevada Water Authority
Department of Resources
1001 S. Valley View Blvd.
Las Vegas, NV 89153
(702) 258 3812

Gary W. Zunino, Biologist
Nevada Department of Transportation
1263 S. Stewart St.
Carson City, NV 89712
(702) 687 5605