[Federal Register: September 19, 2001 (Volume 66, Number 182)]
[Proposed Rules]               
[Page 48225-48227]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]



Fish and Wildlife Service

50 CFR Part 17

RIN 1018-AH83

Endangered and Threatened Wildlife and Plants; Reopening of 
Public Comment Period and Notice of Availability of Draft Economic 
Analysis for Proposed Critical Habitat Determination for the 
Chorizanthe robusta var. robusta (Robust Spineflower)

AGENCY: Fish and Wildlife Service, Interior.

ACTION: Proposed rule; reopening of public comment period and notice of 
availability of draft economic analysis.


SUMMARY: We, the U.S. Fish and Wildlife Service (Service) announce the 
availability of a draft economic analysis for the proposed designation 
of critical habitat for the robust spineflower (Chorizanthe robusta 
var. robusta). We are also providing notice of the reopening of the 
public comment period for the proposal to designate critical

[[Page 48226]]

habitat for this plant to allow all interested parties to comment 
simultaneously on the proposed rule and the associated draft economic 
analysis. Comments previously submitted need not be resubmitted as they 
already have been incorporated into the public record and will be fully 
considered in the final rule. Comments submitted during this comment 
period will also be incorporated into the public record and will be 
fully considered in the final rule.

DATES: The comment period is opened and we will accept comments until 
October 19, 2001. Comments must be received by 5:00 p.m. on the closing 
date. Any comments that are received after the closing date may not be 
considered in the final decision on this proposal.

ADDRESSES: Copies of the draft economic analysis are available on the 
Internet at ``www.r1.fws.gov'' or by writing to the Field Supervisor, 
U.S. Fish and Wildlife Service, Ventura Fish and Wildlife Office, 2493 
Portola Road, Suite B, Ventura, California 93003.
    All written comments should be sent to the Field Supervisor at the 
above address. You may also send comments by electronic mail (e-mail) 
to ``fw1robustsf@r1.fws.gov''. Please submit electronic comments in 
ASCII file format and avoid the use of special characters and 
encryption. Please include ``Attn: RIN 1018-AH83'' and your name and 
return address in your e-mail message. If you do not receive a 
confirmation from the system that we have received your e-mail message, 
contact us directly by calling our Ventura Fish and Wildlife Office at 
phone number 805-644-1766. Comments and materials received will be 
available for public inspection, by appointment, during normal business 
hours at the above Service address.

FOR FURTHER INFORMATION CONTACT: Catrina Martin, Assistant Field 
Supervisor, Ventura Fish and Wildlife Office, at the above address 
(telephone 805-644-1766; facsimile 805-644-3958).



    Chorizanthe robusta var. robusta, also known as robust spineflower 
and Aptos spineflower, is endemic to sandy soils in coastal areas in 
southern Santa Cruz and northern Monterey counties. In California, the 
spineflower genus (Chorizanthe) in the buckwheat family (Polygonaceae) 
comprises species of wiry annual herbs that inhabit dry sandy soils, 
both along the coast and inland. Because of the patchy and limited 
distribution of such soils, many species of Chorizanthe tend to be 
highly localized in their distributions.
    Like other spineflowers, Chorizanthe robusta var. robusta is 
branched from the base and subtended by a rosette of basal leaves. The 
overall appearance of C. r. var. robusta is that of a low-growing herb 
that is soft-hairy and grayish or reddish in color. The plant has an 
erect to spreading or prostrate habit, with large individuals reaching 
50 centimeters (cm) (20 inches (in.)) or more in diameter. This taxon 
is distinguished by white (rarely pinkish) scarious (translucent) 
margins on the lobes of the involucre (circle or collection of modified 
leaves surrounding a flower cluster) or head that subtend the white-to 
rose-colored flowers. The aggregate of flowers (heads) tend to be 1.5 
to 2.0 cm (0.6 to 0.8 in.) across in diameter and distinctly aggregate. 
Chorizanthe robusta var. robusta is one of two varieties of the species 
Chorizanthe robusta. The other variety (Chorizanthe robusta var. 
hartwegii), known as Scotts Valley spineflower, is restricted to the 
Scotts Valley area in the Santa Cruz Mountains.
    Chorizanthe robusta var. robusta is a short-lived annual species. 
It germinates during the winter months and flowers from April through 
June; although pollination ecology has not been studied for this taxon, 
pollinators observed include leaf cutter bees (megachilids), at least 6 
species of butterflies, flies, and sphecid wasps (Randy Morgan, 
biologist, Soquel, California, pers. comm. 2000). Each flower produces 
one seed; depending on the vigor of the individual plant, dozens, if 
not hundred of seeds could be produced. The importance of pollinator 
activity in seed set has been demonstrated by the production of seed 
with low viability where pollinator access was limited (Harding Lawson 
Associates 2000). Seed is collectable through August. The plants turn a 
rusty hue as they dry through the summer months, eventually shattering 
during the fall. Seed dispersal is facilitated by the involucral 
spines, which attach the seed to passing animals. While animal vectors 
most likely facilitate dispersal between colonies and populations, the 
prevailing coastal winds undoubtedly play a part in scattering seed 
within colonies and populations.
    The locations where Chorizanthe robusta var. robusta occurs are 
subject to a mild maritime climate, where fog helps keep summer 
temperatures cool and winter temperatures relatively warm, and provides 
moisture in addition to the normal winter rains. Chorizanthe robusta 
var. robusta is currently known from a total of seven sites. Two sites 
are located on active coastal dunes, while the other five sites are 
located inland from the immediate coast in sandy openings within scrub, 
maritime chaparral, or oak woodland habitats. All of these habitat 
types include microhabitat characteristics that are suitable for C. r. 
var. robusta. First, all sites are on sandy soils; whether the origin 
of the soils are from active dunes or interior fossil dunes is 
apparently unimportant. Second, these sites are relatively open and 
free of other vegetation; sandy soils tend to be nutrient-poor, which 
limits the abundance of other herbaceous species that can grow on them. 
However, if these soils have been enriched, either through the 
accumulation of organic matter or importation of other soils, these 
sandy soils may support more abundant herbaceous vegetation which may 
then compete with C. r. var. robusta. Management of the herb cover, 
either through grazing, mowing or fire, may allow the spineflower to 
persist. In scrub and chaparral communities, C. r. var. robusta does 
not occur under dense stands, but will occur between more widely spaced 
    The current distribution of Chorizanthe robusta var. robusta is 
restricted to coastal and near-coastal sites in southern Santa Cruz 
County and northern Monterey County, ranging from Pogonip Park in the 
city of Santa Cruz, southeast to coastal dunes between Marina and 
Seaside that were formerly part of Fort Ord. With the discovery of two 
new populations in the year 2000, a total of seven populations are now 
known to exist. There is a high likelihood that other populations will 
be discovered in the future.
    Portions of the coastal dune, coastal scrub, grassland, chaparral, 
and oak woodland communities that support Chorizanthe robusta var. 
robusta have been eliminated or altered by recreational use, conversion 
to agriculture, and urban development. Dune communities have also been 
altered in composition by the introduction of non-native species, 
especially Carpobrotus spp. (sea-fig or iceplant) and Ammophila 
arenaria (European beachgrass), in an attempt to stabilize shifting 
sands. In the last decade, significant efforts have been made to 
restore native dune communities, including the elimination of these 
non-native species.
    Pursuant to the Endangered Species Act of 1973, as amended (Act), 
Chorizanthe robusta var. robusta was listed as endangered on February 
4, 1994 (59 FR 5499). On February 15,

[[Page 48227]]

2001, we published in the Federal Register (66 FR 10419) a rule 
proposing critical habitat for the Chorizanthe robusta var. robusta. 
Approximately 660 hectares (1,635 acres) of land fall within the 
boundaries of the proposed critical habitat designation. Proposed 
critical habitat is located in Santa Cruz County, California, as 
described in the proposed rule.
    Section 4(b)(2) of the Act requires that the Secretary shall 
designate or revise critical habitat based upon the best scientific and 
commercial data available and after taking into consideration the 
economic impact of specifying any particular area as critical habitat. 
Based upon the previously published proposal to designate critical 
habitat for the Chorizanthe robusta var. robusta and comments received 
during the previous comment period, we have prepared a draft economic 
analysis of the proposed critical habitat designation. The draft 
economic analysis is available at the above Internet and mailing 

Public Comments Solicited

    We have reopened the comment period at this time in order to accept 
the best and most current scientific and commercial data available 
regarding the proposed critical habitat determination for the robust 
spineflower and the draft economic analysis of proposed critical 
habitat determination. Previously submitted written comments on this 
critical habitat proposal need not be resubmitted. We will accept 
written comments during this reopened comment period. The current 
comment period on this proposal closes on October 4, 2001. Written 
comments may be submitted to the Ventura Fish and Wildlife Office in 
the ADDRESSES section.

    Authority: The authority for this action is the Endangered 
Species Act of 1973 (16 U.S.C. 1531 et seq.).

    Dated: September 7, 2001.
Daniel S. Walsworth,
Acting Manager, California/Nevada Operations Office.
[FR Doc. 01-23249 Filed 9-18-01; 8:45 am]