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Ny r nay _ - P= s 4= —¥ — = -_ ! : e > m v 7 ¥.@ L¥9.17/s5:m 35 (4 s die Matten's principal conservation eqmney, the Department of the Interior has responsibility for most of our nationally owned public lands and natural resources. This includes fostering the wisest use of our land and water resources, protecting our fish and wildlife, preserving the environmental and cultural values of our national parks and historical places, and providing for the enjoyment of life through outdoor recreation. The Department assesses our energy and mineral resources and works to assure that their development is in the best interests of all our people. The Department also has a major responsibility for American Indian reservation communities and for people who live in island Terruindetr Uo.S.r admiiniestrsatio n. RECOVERY PLAN FOR MARSH SANDWORT (Arenaria paludicola) AND GAMBEL’S WATERCRESS (Rorippa gambelii) Published by U.S. Fish and Wildlife Service Portland, Oregon Prepared by Anuja K. Parikh Dr. Nathan Gale and Connie Rutherford Fix U.S. Fish and Wildlife Service 1215 Bajada 2493 Portola Road, Suite B Santa Barbara,9C31A0 9 -. VentuCrA a93,00 3 Approved: Manager, Caii Operations Office, U.S. Fish and Wildfife Service, Region 1 Due Ul L DISCLAIMER. Recovery plans delineate reasonable actions that are believed to be required to recover and/or protect listed species. Plans published by the U.S. Fish and Wildlife Service or National Marine Fisheries Service are sometimes prepared with the assistance of recovery teams, contractors, State agencies, and other affaned inctertesteed pdarti es. Plans are reviewed by the public and submitted to additional peer review before they are adopted by the Services. Objectivofe tsh e plan will be attained and any necessary funds made available subject to budgetary and other constraints affecting the parties involved, as well as the need to address other priorities. Recovery plans do not obligate other parties to undertake specific tasks and may not represent the views nor the official positions or approval of any individuals or agencies involved in the plan formulation other than the U.S. Fish official position of the National Marine Fisheries Service/U.S. Fish and Wildlife Director or Manager, California-Nevada Operations or Director as approved. Approved recovery plans are subject to modification as dictated by new findings, changes in species status, and the completion of recovery tasks. LITERATURE CITATION U.S. Fish and WildlSierfviece . 1998. Recovery Plan for Marsh Sandwort (Arenaria paludicola) and Gambel’s Watercress (Rorippa gambelii). U.S. Fish and Wildlife Service, Portland, Oregon. 50 pp. + appendices Addicopites miay obe pnurchaasedl fr om: Fish and Wildlife ReferenSecrveic e 5430 GrosvLanee,n Suoiter 1 10 Bethesda, Maryland 20814 telephone: 301/492-6403 or 1-800-582-3421 fax: 301/564-4059 7 ACKNOWLEDGEMENTS The ‘ollowing people provided assistance by supplying information, and/or reviewing an early draft of the plan: Donovan Bailey, Cornell University; Ray Belknap, Land Conservancy of San Luis Obispo County; John Chesnut, a botanical consultant, Tree Totalers, Los Osos; David Chipping, California Native Plant Society; Wayne Ferren, Museum of Systematics and Ecology, University of California, Santa Barbara; David Gurnee, Arroyo Grande; Diana Hickson, California Department of Fish and Game; Debbie Hillyard, California Department of Fish and Game; Dr. David Keil, California Polytechnic State University, San Luis Obispo; Jenny Langford, Land Conservancy of San Luis Obispo County; Dr Susan Mazer, University of California, Santa Barbara; Dr. Robert Price, University of Georgia; Tricia Waddell, University of California, Santa Barbara; Chuck Warner, The Nature Conservancy; and Eric Wier, County of San Luis Obispo. The Fish and Wildlife Service acknowledges the following for permission to mary arate Stanford University Press — Rorippa gambelii. From Le Roy Abrams and R:S. Ferris, Illuflsorat ofr thae Patcifeic dstat es. VolumeII . The illustratiiso nb y JeanR.n Jaenis h University of California Press — Rorippa gambelii, from James C. Hickman, editor. 1993. The Jepson manual: higher plants of California. The illustratioins by Dr. Linda Ann Vorobik. Copyright © 1993 Regents of the University of Californi University of California Press — Arenaria paludicola, from Herbert Mason. 1957. A Flora of the marshes of California. The illustisr bya Mtariy oBanrna s Pomeroy. Copyright © 1957 Regents of the University of California, © renewed 1985 Herbert Mason. California Native Plant Society — photographs by Malcolm McLeod and Robert Price, from the Society’s rare plant slide collection. )/ EXECUTIVE SUMMARY Current Status: Arenaria paludicola and Rorippa gambelii are federally listed as endangered. Both have recently been collected in central or southern Mexico, but little is known of their status. In the United States, Arenaria paludicola is found in only two populations, one of fewer than 10 individuals in Black Lake Canyon; the other of more than 85 individuals at Oso Flaco Lake, San Luis Obispo County, California. Three populations of Rorippa gambelii are currently known in the United States — one with about 500 individuals in Black Lake Canyon near the A. paludicola population, one with about 300 individur's at Little Oso Flaco Lake, also in San Luis Obispo County, and a third population of approximately 100 plants on Vandenberg Air Force Base, Santa Barbara County. Habitat Requiraned Lmimietinng tFacstor s: Both species occur in wetland areas with standing water or saturated acidic soils from sea level to 450 meters (1,480 feet). Both are threatened by encroaching native and alien vegetation and off road vehiclusee . In addition, the very low numbers of individuals and populations put these species at great risk of extinction due to random naturally occurring events. Recovery Objective: Reclassify to threatened status. Reclassification Criteria: These species can be considered for downlisting to threatened when: 1. New plants of each species are established so that there are at least 5 popuof lat laeastt 500i indoividnualss ea ch. 2. These populations occur in permanently protected habitats within the species’ historical ranges. 3. The populations remain viable (self sustaining through natural reproduction and stable or increasing in size) for at least 5 years. Actions needed: 1. Protect, maintain, and enhance species habitats 2. Monitor and document species populations and habitat characteristics 3. Conduct research on the ecology and biology of the species 4. Increase size of existing populations 6. Evaluate progress and update management and recovery guidelines Recovery Costs, in thousands of dollars: Year Necd1 Need2 Need3 Need4 NeedS Need6 Total FY! 46.75 102 15.0 18.25 4.0 0 88.7 FY2 41.25 112 13.0 14.25 4.0 0 80.45 FY3 38.25 5.7 13.0 19.25 ° 0 76.2 * FY4 37.25 42 13.0 75 ° 0 61.95* FYS 42.25 42 13.0 1.5 ° 0 60.95* FY6 2625 42 0 1.5 ° 0 31.95* FY7 2625 42 0 1.5 ° 4.0 35.95° FY8 625 42 0 1.5 ° 11.95* FY9 625 42 0 1.5 . 0 11.95° FY10 625 42 0 1.5 ° 0 11.95° Total 2775 565 67.0 68.25 8.0° 4.0 481.25° * Some costs are yet to be determined Date of Downlisting: if the proposed recovery actions are successful, downlisting from endangered to threatened might be possible by 2007. Aftfivee yrear s, progress toward meeting the downlisting criteria should be evaluated, and a target date shouble sdet . TABOF LCONETEN TS Page lnse o n osopecesesiessscncbes l EEE SE en ee ee l B. Taxoannd oDesmcriypti on ......66 .c c.cec.cc .cec.e e.eee.ee es 2 BEES ARS Ce a a Pe aT ee 7 D. Habitat Requirements ..... 2... 2.66. c cece cece ce cee eeeeees 12 ih th hbk occlte cin conhece cys 6600600000esbabeetes 13 F. Reasons for Listing and Current Threats ...................045- 18 G. Conservation Measawes ... 2... cece cece eee eeceees 24 Se TT nscbbbccecesces cccccececessecenneoesese 28 Ee See | ere 30 A. Objectanid vCreitersia. .. 2.0... cece eee eee eeeee 30 By SEED circ ccccccccccccccccccosccccoccoccccece 31 1. Protect, maintain, and enhance species habitats ............. 31 2. Document and monitor population and habitat characteristics . . 35 3. Couduct research on the ecology and biology of the species . . . . 36 4. Augment existing populations ................ceeeceseees 38 5. Estambewl poipuslathion s ..............ccceceeceseeees 39 6. ee I TITITTTTIT TTTT ITT TTTT TTTT Tee 42 Sb GOCE coccccsccccedoccccccccccccccccsceccccoccs 43 VI LIST OF FIGUANRD ETASBLE S Page Figure1 . Illusotf Arrenaarita ipaloudincol a ...............ccccceeeeeess 4 Figure2 . Illusotfr Roraiptpai gaombneli i ...............0ccccceceeeeces 5 Figure 3. Photos of Arenaria paludicola and Rorippa gambelii. ............. 6 Figure4 . Distributions of Arenaria paludicola and Rorippa gambelii ....... .1 4 Figure 5. Habitat of Arenaria paludicola and Rorippa gambelii ............ 15 Figure6 . Arenaria paludicola habitat. .............0000ccecccceeeceeee 16 Table1 . The Status of Historical Sites for Arenaria paludicola............. 2 Table2 . The Status ofH istorical Sites for Rorippa gambelii ............... 23 Vi) IL.I NTRODUCTION A. BRIEF OVERVIEW The final rule determining Federal endangered status for the plant species marsh sandwort (Arenaria paludicola Robinson) and Gambel’s watercress (Rorippa gambelii (S. Watson) Rollins & Al-Shehbaz)) was published in the August 3, 1993, Federal Regist(5e8 rF R 41378). Arenaria paludicola has a recovery priority of 5; Rorippa gambelii has a recovery priority of 2. Recovery priorities for listed species range from i to 18, with | being the highest priority. A priority of 2 indicates a species facing a high degree of threat but also having a high potential for recovery; a priority of 5 indicates high threat and a low potenfotr irecaovlery . In 1990, Arenaria paludicola and Rorippa gambelii were listed as endangered and threatened, respectively, by the State of California (Morey 1990; Wickenheiser and Morey 1990; Skinner and Pavlik 1994). Arenaria paludicola is currently known from only two populations — one comprising fewer than 10 individuals in Black Lake Canyon, the other of more then 85 individuals at Oso Flaco Lake, both in San Luis Obispo County, California. Three populationosf Rorippa gambelii are currently known — one with about 500 individuals in Black Lake Canyon near the A. paludicola population, one other with about 300 individuals at Little Oso Flaco Lake, also in San Luis Obispo County, and a third population of approximately 100 plants on Vandenberg Air Force Base, Santa Barbara County. This recovery plan for the two species summarizes past and present knowledge concerning their range, habitat requirements and population ecology. Additionally,i t discusses threats to their existence, as well as past and present research and conservation efforts directed at maintaining their survival. The plan delianctieonsa tto bee tsak en toward recovery of the two species. This recovery plan is one of several being developed to conserve listed species of coastal Caliandf thoeir reconsystiemsa (¢ .g. U.S. Fish and WildlSiefrveic e 1997, 1998). The plans are intended to complement each other.