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Home , Cadlina luteomarginata, Calliostoma ligatum, Crepipatella lingulata, Katharina tunicata, Lottia limatula, Lottia persona

Monographs of the Western North American Naturalist 7, © 2014, pp. 260–275

STATUS AND TRENDS OF THE ROCKY INTERTIDAL ON THE FARALLON ISLANDS

Jan Roletto1, Scott Kimura2, Natalie Cosentino-Manning3, Ryan Berger4, and Russell Bradley4

ABSTRACT.—The Farallon Islands in the Gulf of the Farallones National Marine Sanctuary (GFNMS) is a 7-island chain located 48 km west of San Francisco, California. Since 1993, GFNMS biologists and associates have monitored algal and invertebrate abundances on the intertidal shores of the 2 South Farallon Islands. The monitoring occurred 1–3 times yearly in 6 study areas. In each study area, 3–4 permanent, 0.15-m2 quadrats located between the upper and midintertidal zones were sampled for algal and sessile invertebrate cover and invertebrate counts. Taxonomic surveys were also completed to document other species in the vicinity of the sampling quadrats and to further charac- terize the sampling areas. Here we report monitoring results for the period 1993 to 2011. While species richness has remained relatively stable and high compared to the nearest mainland sites (Sonoma County through San Mateo County), there has been a slow, long-term net decline in the abundance of algal species and mussels at various sites on the islands. Causes for the declines remain unknown, but increased trampling from rising numbers of pinnipeds and increased waste from pinnipeds and seabirds are among the influences suspected to be important.

RESUMEN.—Las Islas Farallon en el Santuario Nacional Marino Golfo de Farallones (SNMGF) es un archipiélago de siete islas situado a 48 km al oeste de San Francisco, California. Desde 1993, los biólogos y asociados del SNMGF han monitoreado la abundancia de especies de algas e invertebrados en las costas intermareales de las dos Islas Farallon del sur. El seguimiento se produjo una a tres veces al año en seis áreas de estudio, en los que se estudiaron de tres a cuatro cuadrantes permanentes de 0.15 m2 situados entre las zonas intermareales superior y media donde se muestrearon la cubierta de algas y el número de invertebrados sésiles. Adicionalmente, se realizaron estudios taxonómicos para docu- mentar otras especies y caracterizar las áreas de muestreo en las proximidades de los cuadrantes. Aquí incluimos los resultados del monitoreo para el período entre 1993 y 2011. Mientras que la riqueza de especies se ha mantenido relati- vamente estable y elevada en comparación con otros sitios de muestreo cercanos en el continente (Condado de Sonoma a al Condado de San Mateo), se ha observado un lento descenso neto a largo plazo en la abundancia de especies de algas y mejillones en varios sitios en las islas. Las causas de este descenso siguen siendo desconocidas, pero se sospecha que la influencia del aumentó en el pisoteo del creciente número de pinnípedos y el aumento de los residuos de pinnípedos y aves marinas son importantes.

The Farallon Islands in the Gulf of the Far- the islands are within the Farallon National allones National Marine Sanctuary (GFNMS) Wildlife Refuge. Below the mean high-tide is a chain of 7 islands and emergent rocky level, the intertidal and subtidal areas are pinnacles located 48 km (30 mi) west of San within GFNMS and are recognized and Francisco, California, 37°42N and 123°00W designated by the State Water Resources (Fig. 1). The islands and pinnacles are part of Control Board as an Area of Special Biological a granitic submarine ridge flanking the con- Significance (ASBS). Furthermore, portions of tinental shelf (Blankinship and Keeler 1892, the islands’ intertidal and subtidal are desig- Hanna 1951). They are recognized as an nated as State Marine Protected Areas (MPAs), ecosystem unique for its location and diver - which were created by the Pro- sity of species across a broad range of bio- tection Act passed by the California State logical communities. For these reasons, the Legislature in 1999. At the Farallon Islands habitats and natural resources at the islands are 2 state marine reserves, 2 special closure and emergent pinnacles are afforded many areas, and one state marine conservation levels of resource management, protection, area. Also, the islands are not open to public conservation, and oversight. Above the mean visitation, and access is by permit and for high-tide level, the terrestrial portions of scientific purposes only.

1Gulf of the Farallones National Marine Sanctuary, 991 Marine Dr., San Francisco, CA 94129. E-mail: [email protected] 2Tenera Environmental, 141 Suburban Rd., Suite A2, San Luis Obispo, CA 93401. 3National Oceanic and Atmospheric Administration, Fisheries Restoration Center, 777 Sonoma Ave., Santa Rosa, CA 95404. 4Point Blue (formerly PRBO) Conservation Science, 3820 Cypress Drive #11, Petaluma, CA 94954.

260 2014] INTERTIDAL FARALLON 261

Fig. 1. Sanctuary Ecosystem Assessment Surveys (SEAS) rocky intertidal study areas on the South Farallon Islands, California (37°42 N, 123°00 W). Dots indicate locations of the 6 study areas. Map data (left panel): ©2012 Google, LDEO-Columbia, NSF, NOAA, SIO, NOAA, U.S. Navy, NGA, GEBCO, MBARI, Image Landsat. Map data (right panel): ©2008 Google, SIO, NOAA, U.S. Navy, NGA, GEBCO, CSUMB SFML, CA OPC.

Blankinship and Keeler (1892) completed Islands), which are the 2 largest of the 7 the first survey of the intertidal community islands (Fig. 1). Together these islands are 44 on the Farallon Islands. Their work provided ha in size and are separated by a narrow surge a general description of the island’s geology channel. A narrow and discontinuous reef and biota and a temporal snapshot of the inter- characterizes the , exposed only tidal community. The next intertidal survey on minus tides. The landward rise is often was 87 years later, completed by the California steep, highly worn, and characterized by cracks State Water Resources Control Board as a and crevices, surge channels, and sea caves reconnaissance survey to consider designation (Hanna 1951). No rocks or boulder fields are of the islands as an ASBS (CSWRCB 1979). found in the upper intertidal, and the only The only other published investigations in - sand is coarse grained, with cobbles deposited volving assessment or documentation of the at the heads of surge channels. Intertidal zones intertidal habitat on the islands focused on were categorized based on species composi- the distribution of Foraminifera (Grivetti 1962) tion. Many locations on the islands are used as and the systematics of Porifera (Klontz 1989). seasonal and year-round haul-outs for pin- Since 1993 and as part of the Sanctuary nipeds. As such, the study areas selected were Eco system Assessment Surveys (SEAS), the accessible and disturbance to pinnipeds (and GFNMS has monitored intertidal algal and seabirds) was minimized, as required by the invertebrate species abundances on the rocky Sanctuary and Refuge permits. The number shores of the 2 South Farallon Islands (Southeast of study areas and number of quadrats in Farallon and Maintop Islands). The long-term each study area were also selected based on monitoring program was created to characterize logistics and funding. See Appendix 1 for the the intertidal habitat and to maintain an ongoing physical descriptions of each study area and database of species abundances in the event of quadrat. oil spills. Here we present data spanning August Sampling Design 1993–February 2011 summarizing macroalgal and invertebrate changes on the Farallon Islands. Three to four permanent, 30 × 50-cm quadrats (0.15 m2) between the upper and METHODS midintertidal zones (Ricketts et al. 1985) were sampled in each of the 6 study areas (Fig. 1). Study Areas The quadrat locations were marked with There are 6 study areas on the 2 South Far- marine epoxy on the rock substrate. Sampling allon Islands (Southeast Farallon and Maintop was completed up to 3 times annually (August, 262 MONOGRAPHS OF THE WESTERN NORTH AMERICAN NATURALIST [Volume 7

November, February), beginning in 1993. three are presently considered to be rare in Sampling was not scheduled to occur during the sampling region or outside their normal the peak algal growth season (May–July) to range: Branchioglossum undulatum and Myri- minimize and avoid disturbance to breeding ogramme variegata have not been previously seabirds and pinnipeds that typically use the documented north of Carmel Bay, California, sampling areas. and Ulva conglobata is considered an intro- All surveys included taking photographs of duced species. each quadrat followed by point-intercept sam- Species abundances, averaged across all 6 pling, which consisted of sampling 50 random study areas for 2010 and 2011 (the most recent points for algal and sessile invertebrate cover. sampling years), revealed that the top 10 All algal and sessile invertebrate species under species comprised >90% of the total upright each sampling point were identified and re- algal cover for those 2 years combined. Species corded to the lowest taxonomic level practical abundance was variable across the 6 study (Foster et al. 1991, Dethier et al. 1993). Multiple areas, except for the articulated coralline algal layers of the same species (taxon) at a single species Corallina vancouveriensis, which was sampling point were tallied as a single occur- either the first or second most abundant rence, but layers of multiple species under a species (>20% mean cover) in the study areas single point resulted in multiple tallies (con- (Table 1). The Mazzaella flaccida-complex, a tacts) per sampling point. As such, total algal foliose red algal assemblage, was also abun- cover (all species tallies combined for a quadrat) dant, except in the quadrats at Mussel Flat, could exceed 100% cover for highly layered where Anthopleura elegantissima covered large quadrats. Point-intercept assessments in each amounts of the substrate. The Mazzaella flac- quadrat also included a tally of dead cida-complex consisted of several species of (i.e., empty tests or shells and per- Mazzaella, with M. flaccida being the most centage of dead or bleached algae/plants) abundant. The green sea lettuce Ulva spp., the and the number of contacts of bare (uncolo- branched turf alga Gelidium spp., the red nized) rock or sand and crustose species bladed alga , and nail across the sampling points. brush seaweed Endocladia muricata were con- Invertebrate densities within each quadrat sistently found at each of the study areas, but were based on counts of select species (taxa) abundance was variable, typically <20% mean within 25 × 25-cm and 10 × 10-cm subquadrats, cover in each area. The most commonly sam- nested within the 30 × 50-cm quadrats. Data pled invertebrates included mussels Mytilus are presented here only for Mytilus califor- californianus, aggregating anemones Antho- nianus, due to low occurrences of other inver- pleura elegantissima, and the Tetra- tebrates. clita rubescens and Balanus spp. Algal and invertebrate species of uncertain From 1993 through 2011, upright (noncrus- identity were collected from outside the tose) algal species declined in abundance (Fig. quadrat and identified in the laboratory. Iden- 2). Total upright algal abundance at Low Arch, tifications were based primarily on Dawson for example, declined from nearly 240% mean and Foster (1966), Kozloff (1983), Smith and cover to approximately 140% mean cover. At Carlton (1975), Abbott and Hollenberg (1976), all study areas, the decline was offset by and Carlton 2007. Algal voucher specimens increases in crustose algal cover, which was are presently archived at the GFNMS office in greatest at Dead Sea Lion Flat where the San Francisco, California, and at the Univer- combined coverage of crustose species in- sity of California, Berkeley, Jepson Herbarium. creased from <10% mean cover to >50% mean cover from 1993 to 2011 (Fig. 3). The RESULTS decline in algal cover is also substantiated by a corresponding increase in uncolonized (bare For the period February 1993–February rock or sand) substrate in all areas (Fig. 4). 2011, the rocky intertidal species inventory While an overall decline in the combined for the South Farallon Islands consisted of coverage of upright algal species was de - 223 invertebrate taxa, 7 fish taxa, 187 algal tected, the average number of species sampled taxa, and 1 seagrass taxon (Appendixes 2–4). in each quadrat (i.e., species richness) over the Of all the algal species listed in Appendix 4, long term has not exhibited the same trend, 2014] INTERTIDAL FARALLON 263

TABLE 1. Mean percent cover of taxa sampled in permanent point-intercept quadrats on the South Farallon Islands, 2010–2011.

______Southeast Farallon Island ______Maintop Island Blow Hole Dead Sea Mussel Low Drunk Uncle Raven’s Peninsula Lion Flat Flat Arch Islet Cliff Species Bossiella/Calliarthron spp. 1.3 0.5 0 0.3 0 10 Corallina vancouveriensis 20.8 21.5 17.3 58.7 27.3 48.8 Cryptopleura/Hymenena spp. 100401.5 Egregia menziesii 800000 Endocladia muricata 16.5 0 4.3 0 1 0.8 filamentous green algae 0 0 7.8 0.3 0 0 filamentous red algae 0 0 10 0 0 0 Gelidium spp. 1 1 4.5 0.3 7 1 Mastocarpus jardinii 0 0 0.3 5.7 0.3 0 Mastocarpus papillatus 3.84362.37.8 Mazzaella affinis 0.8 0.3 3.8 0.3 0 0 Mazzaella flaccida-complex 34 23.8 0.3 41.3 1.3 15 Microcladia borealis 0 0.3 0.5 0 0.3 3 Microcladia coulteri 000.3000 Neogastroclonium subarticulatum 4.5 0.3 0.5 0 0 0 Neorhodomela larix 08.80000 Osmundea spectabilis 000000.3 Phyllospadix scouleri 030007.3 Plocamium spp. 0 0 0.8 0 0 0 Porphyra spp. 000001.8 Prionitis spp. 0 0.8 0 3 2.7 5.5 Ulva spp. 4.5 16.8 6 0 0 1.3 Mean number of noncrustose species 9.6 9.5 10.5 8 6.5 12 Crustose coralline complex 4.5 8.5 9.8 16.7 1.3 9.8 Crustose noncoralline complex 6.3 37.3 14 3.7 12.3 4 Bare rock/sand % cover 34.5 20 31 42.7 30 29.5 Barnacles % cover 0.5 0 5.8 4 11.3 3.3 Mussels % cover 45.3 0 0 0.3 35.3 23 Anemones % cover 0 0 25.3 0 0 0 Mean number of dead invertebrates 0.3 0.1 1.8 0.2 2.2 12 Bleached plants % cover 0.3 2.8 3.8 1.3 1.7 10.3

although taxon numbers have been variable DISCUSSION within and between years (Fig. 5). As with the upright algal species, Mytilus There was a conspicuous absence of rock- californianus declined at all locations that weeds (Fucales) on the islands. In particular, had sufficient numbers of M. californianus to Fucus distichus and Silvetia compressa (previ- quantify (Figs. 6, 7). Mussel cover at Blow ously fastigiata) were not found in 18 Hole Peninsula declined from approximately years of sampling. Prior to the beginning of 75% mean cover to approximately 45% mean the SEAS monitoring program in 1993, these 2 rockweed species were noted on the islands cover; and at Low Arch, mussel cover declined by Blankinship and Keeler (1892) and CSWRCB to nearly zero abundance. The decline in mus- (1979). It is not known if these records consti- sel cover corresponded to similar declines in tuted an error in reporting by the investigators mussel densities (Fig. 7). For example, mus- or if both species were actually present. The sel densities at Blow Hole Peninsula declined only rockweed species observed since then –2 from ap proximately 180 mussels ⋅ 0.15 m to has been Fucus distichus occurring only as approximately 135 mussels ⋅ 0.15 m–2 and at floating, detached drift near the islands (Co - Drunk Uncle Islet densities declined from sentino et al. 2001). In contrast, rockweed approximately 92 mussels ⋅ 0.15 m–2 to 33 species have been and continue to be very mussels ⋅ 0.15 m–2 (Fig. 7). In areas where common and abundant on mainland shores in mussels were less common, such as Low Arch, Central and Northern California (Cosentino et mussels became almost absent in 2011. al. 2001, Tenera, Inc. 2011). 264 MONOGRAPHS OF THE WESTERN NORTH AMERICAN NATURALIST [Volume 7 Mean percent cover noncrustose algal species Mean percent cover noncrustose algal species

Fig. 2. Change in percent cover of all upright, noncrustose algal species at the SEAS study areas on the South Farallon Islands, 1993–2011. 2014] INTERTIDAL FARALLON 265 Mean percent cover crustose algal species Mean percent cover crustose algal species

Fig. 3. Change in percent cover of all crustose algal species at the SEAS study areas on the South Farallon Islands, 1993–2011. 266 MONOGRAPHS OF THE WESTERN NORTH AMERICAN NATURALIST [Volume 7 uncolonized area Mean percent cover uncolonized area Mean percent cover

Fig. 4. Change in percent cover of uncolonized area (bare rock and sand) at the SEAS study areas on the South Farallon Islands, 1993–2011. 2014] INTERTIDAL FARALLON 267 species richness Number of taxa sampled species richness Number of taxa sampled

Fig. 5. Change in species richness (total taxa sampled) at the SEAS study areas on the South Farallon Islands, 1993–2011. 268 MONOGRAPHS OF THE WESTERN NORTH AMERICAN NATURALIST [Volume 7 Mean percent cover Mytilus californianus Mean percent cover Mytilus californianus

Fig. 6. Change in percent cover of Mytilus californianus at the SEAS study areas on the South Farallon Islands, 1993–2011. 2014] INTERTIDAL FARALLON 269 2 Mytilus californianus Mean individuals per 0.15 m 2 Mytilus californianus Mean individuals per 0.15 m

Fig. 7. Change in density of Mytilus californianus at the SEAS study areas on the South Farallon Islands, 2000–2011.

The data reported here for the 18-year period increase in bare substrate cover and crustose (1993–2011) on the South Farallon Islands algal cover. However, short-term changes reveal a slow, long-term decline in overall algal within this time span do not necessarily reflect and mussel abundance and a corresponding the same shift but instead reveal much within 270 MONOGRAPHS OF THE WESTERN NORTH AMERICAN NATURALIST [Volume 7 and between year variation (increases and The declines of mussels and algae detected decreases) among study areas. This variation in the monitoring on the South Farallon can be associated with sampling error and Islands appear unique, as declines of similar observer variation. Different sets of biologists nature have not been reported for nearby sites sampled the quadrats among the various sur- along the mainland coast (MARINe 2013). As veys, and this may account for a portion of such, further investigations of the relationship the data variation within and between years between the declines and rising pinniped and among study areas. However, the overall and seabird populations, and possible climate decrease in total noncrustose algal cover and change (e.g., sea surface temperatures, up- mussel abundance from 1993 to 2011 exceeds welling, Pacific Decadal Oscillation) are war- the short-term interannual variations in the ranted to help establish cause-and-effect data potentially associated with observer varia- relationships between the intertidal biota on tion. This pattern provides evidence in sup- the Farallon Islands and factors influencing port of the long-term changes detected and changes to the intertidal community. Further underscores the importance of conducting investigations are warranted to determine if studies over long periods of time (i.e., decades) the changes to the intertidal community on the to ensure that changes detected in abundances islands relative to the mainland communities are not artifacts of sampling errors related to represent a unique set of species’ responses to observer variation. an atypical set of environmental influences at The causes for the long-term declines in the islands. algal cover and mussel abundance remain unknown. Sea surface temperatures (SST) are ACKNOWLEDGMENTS known to influence the composition and abun- dance of intertidal species, spore and larval We thank Gregor Cailliet, Judith Connor, distribution, grazing, , and vulnera- Robert Lea, and John Tarpley for their guidance, bility to disease (Sagarin et al. 1999, Steinbeck comments, and assistance in the development et al. 2005, Petes et al. 2008). Of note, there of this project. Field assistance was provided was a large temperature increase in the pres - by Candice Brown, Maria Brown, Tony Chess, ent study period associated with the 1997– Gery Cox, Kathleen Dickey, Ellen Gartside, 1998 El Niño followed by declines in tempera- Charleen Gavette, Leslie Grella, Daphne Hatch, ture regimes. However, upwelling strength Dan Howard, Brain Jarvis, Rebecca Johnson, (inferred productivity) did not necessarily Amber Mace, Steven Morgan, Gillian O’Do- increase with the overall decrease in water herty, David Osorio, Carol Preston, Tim Reed, temperatures (Abraham and Sydeman 2004, Mary Jane Schramm, Emily Siegel, Jordan PFEL 2013). As such, the relationship between Stout, Sage Tezak, Brigit Ueber, Ed Ueber, declines in algal and mussel abundance and Jennifer Vick, Amity Wood, and Angie Wul- shifts in water temperature regimes and fow, and by data-entry interns Cheryl Chen nutrient associations remain unresolved. Be - and Michael Falzone. Tony Chess, Gery Cox, cause public access is prohibited on the South Ellen Gartside, Dan Howard, and Rebecca Farallon Islands, resource extraction and tram- Johnson made invertebrate identifications. pling from humans are discounted as causes Katie McGortey and Robert Lea made fish for the declines. On the other hand, the identifications. We gratefully acknowledge the declines are coincidental with (1) increased help and consultation of Drs. Kathy Anne numbers of pinnepeds (Point Blue 2012) Miller, Tom De Cew, and Paul Silva, University hauling out on intertidal areas to rest, breed, of California. Logistical support came from nurse, and molt and (2) a large increase in Point Blue (formerly PRBO) Conservation overall seabird numbers on the islands Science staff Derek Lee, Elizabeth McLaren, (Warzybok et al. 2012). Accordingly, the de- Jerry Nussbaum, Peter Pyle, Bill Sydeman, clines may be due in part to a trampling effect and Jim Tietz; and from U.S. Fish and Wildlife from pinnipeds, similar to what occurs from Service, Farallon National Wildlife Refuge human activity on rocky shores (Boal 1980). staff Joelle Buffa, Gerry McChesney, Michael The changes may also be influenced by in - Parker, and Jean Takekawa. The United States creased nutrient and uric acid loading from Coast Guard, Oceanic Society Expeditions, pinniped and seabird wastes. Farallon Island Patrol, and Mick Menigoz of 2014] INTERTIDAL FARALLON 271 the New Superfish provided transportation GRIVETTI, L.E. 1962. Recent intertidal foraminifera of the to the island. Jaime Jahncke of Point Blue Farallon Islands. Master’s thesis, University of Cali- fornia, Berkeley, CA. Conservation Science provided the Spanish HANNA, G.D. 1951. Geology of the Farallon Islands. Cali- translation of the abstract, and John Steinbeck fornia Division Mines Bulletin 154:301–310. provided a critical review of the manuscript. KLONTZ, S.W. 1989. Ecology and systematics of the This work was authorized under the following intertidal of Southeast Farallon Island. permits: GFNMS-03-92, GFNMS-2011-004, Master’s thesis, San Francisco State University, San Francisco, CA. and Special Use Permit #76587, Farallones KOZLOFF, E.N. 1983. Seashore life of the Northern Pacific National Wildlife Refuge, USFWS. This is Coast. University of Washington Press, Seattle, WA. Point Blue Conservation Science scientific MARINe. 2013. Multi-agency Rocky Intertidal Network. contribution #1956. Available from: http://www.pacificrockyinteridal.org PFEL. 2013. Homepage [online]. Pacific Fisheries Envi- ronmental Laboratory, National Marine Fisheries LITERATURE CITED Service, Pacific Grove, CA. Available from: http:// www.pfeg.noaa.gov ABBOTT, I.A., AND G.J. HOLLENBERG. 1976. Marine algae of PETES, L.E., M.E. MOUCHKA, R.H. MILSTON-CLEMENTS, California. Stanford University Press, Stanford, CA. T.S. M OMODA, AND B.A. MENGE. 2008. Effects of ABRAHAM, C.L., AND W. J. S YDEMAN. 2004. climate, environmental stress on intertidal mussels and their euphausiids and auklet nesting: inter-annual trends sea star predators. Oecologia 156:671–680. and variation in phenology, diet and growth of a POINT BLUE. 2012. Pont Blue Conservation Science (for- planktivorous seabird, Ptychoramphus aleuticus. merly PRBO). Unpublished data. Petaluma, CA. Marine Ecology Progress Series 274:235–250. RICKETTS, E., J. CALVIN, AND J. HEDGEPETH. 1985. Between BLANKINSHIP, J.W., AND C.A. KEELER. 1892. On the natural Pacific Tides. 5th edition, revised by D.W. Phillips. history of the Farallon Islands. Zoe 3:144–186. Stanford University Press, Stanford, CA. BOAL, J. 1980. Pacific harbor seal (Phoca vitulina SAGARIN, R.D., J.P. BARRY, S.E. GILMAN, AND C.H. BAXTER. richardii). Haul out impact on the rocky midtidal 1999. Climate-related change in an intertidal com- zone. Marine Ecology Progress Series 2:265–269. munity over short and long time scales. Ecological [CSWRCB] CALIFORNIA STATE WATER RESOURCES CON- Monographs 69:465–490. TROL BOARD. 1979. California marine waters areas of STEINBECK, J.R., D.R. SCHIEL, AND M.S. FOSTER. 2005. special biological significance reconnaissance survey Detecting long-term change in complex communi- report: Farallon Island. Water Quality Monitoring ties: a case study from the rocky intertidal zone. Report No. 79–13, Sacramento, CA. Ecological Applications 15:1813–1832. CARLTON, J.T., EDITOR. 2007. The Light and Smith manual: SMITH, R.I., AND J.T. CARLTON, EDITORS. 1975. Light’s intertidal invertebrates from central California to manual: intertidal invertebrates of the Central Cali- Oregon. 4th edition. University of California Press, fornia Coast. 3rd edition. University of California Berkeley, CA. Press, Berkeley, CA. COSENTINO, N., J. ROLETTO, D.A. OSORIO, AND E. UEBER. TENERA, INC. 2011. S/S Cape Mohican restoration project, 2001. Rocky intertidal communities at the Farallon baseline study and resource stewardship assessment Islands, California. Status report, 2000. National report. Unpublished report to Gulf of the Farallones Oceanic and Atmospheric Administration, Gulf of National Marine Sanctuary, San Francisco, CA. the Farallones National Marine Sanctuary, San Fran- Available from: http://www.marine.gov/Research/ cisco, CA. Species.html DAWSON, E.Y., AND M.S. FOSTER. 1966. Seashore plants of WARZYBOK, P.M., R.W. BERGER, AND R.W. BRADLEY. 2012. California. University of California Press, Berkeley, CA. Population size and reproductive performance of DETHIER, M.N., E.S. GRAHAM, S. COHEN, AND L.M. TEAR. seabirds on Southeast Farallon Island, 2012. Unpub- 1993. Visual versus random-point percent cover lished report to the U.S. Fish and Wildlife Service. estimations: “objective” is not always better. Marine PRBO Conservation Science, Petaluma, CA. Ecology Progress Series 96:93–100. FOSTER, M.S., C. HARROLD, AND D.D. HARDIN. 1991. Received 7 April 2013 Point vs. photo quadrat estimates of the cover of Accepted 23 May 2014 sessile marine organisms. Journal of Experimental Early online 15 December 2014 Marine Biology and Ecology 146:193–203.

Appendix 1 on page 272. Appendix 2 on page 272. Appendix 3 on page 274. Appendix 4 on page 274. 272 MONOGRAPHS OF THE WESTERN NORTH AMERICAN NATURALIST [Volume 7

APPENDIX 1.—Quadrat descriptions. See Fig. 1 for exposure of wave direction at each sample area. Height above Used as zero mean pinniped Quadrat number Area Zone Exposure tide (m) haul-out Q1 Blow Hole Peninsula Mid Semiexposed 1.6 rare Q2 Blow Hole Peninsula Mid Semiexposed 2.1 rare Q3 Blow Hole Peninsula Mid Exposed 2 rare Q101 Blow Hole Peninsula High Semiexposed 1.8 rare Q4 Dead Sea Lion Flat Mid Semiexposed 1.4 yes Q5 Dead Sea Lion Flat Mid Semiexposed 1.3 yes Q6 Dead Sea Lion Flat High Semiexposed 1.7 yes Q103a Dead Sea Lion Flat Low Semiexposed 0.8 yes Q7 Drunk Uncle Islet Low Semiexposed 0.7 yes Q9 Drunk Uncle Islet Low Exposed 0.7 yes Q104 Drunk Uncle Islet High Semiexposed 2.1 yes Q105 Drunk Uncle Islet Mid Semiexposed 1.5 yes Q10 Raven’s Cliff Mid Exposed 1.7 yes Q11 Raven’s Cliff Low Semiexposed 0.4 yes Q12 Raven’s Cliff Low Semiexposed 0.7 yes Q13 Raven’s Cliff High Exposed 3.3 yes Q14 Raven’s Cliff Mid Semiexposed 1.7 yes Q15 Raven’s Cliff Mid Semiexposed 1.2 yes Q16 Low Arch Mid Semiexposed 1.5 yes Q17 Low Arch Mid Semiexposed 1.5 yes Q18 Low Arch High Semiexposed 1.8 yes Q19b Mussel Flat Mid Protected 0.3 no Q20b Mussel Flat Mid Protected 0.4 no Q22b Mussel Flat Low Protected 0.5 no Q102b Mussel Flat High Protected 2 no aQuadrat 103 is the only quadrat with a sandy substrate. bQuadrats 19, 20, 22, and 102 are on steeply sloping or vertical walls and are not subjected to trampling from pinnipeds.

APPENDIX 2. South Farallon Islands intertidal inverte- brate species inventory, as of February 2011. APPENDIX 2. Continued.

ANNELIDA Fabia subquadrata Arabella iricolor Gnorimosphaeroma sp. Dodecaceria fewkesi Hemigrapsus nudus Nereis guberi Hyale grandicornis Phragmatopoma californica Ianiropsis kincaidi Phyllochaetopterus prolifica Idotea fewkesi vermicularis Idotea resecata borealis Idotea schmitti Thelepus crispus Idotea stenops ARTHROPODA Idotea urotoma Acanthomysis sp. Idotea wosnesenskii Achelia chelata Lecythorychus hilgendorfi Achelia nudiscula Ligia occidentalis Achelia spinoseta Ligia pallasii Allorchestes anceps Limnoria algarum Alpheus dentipes Littorophiloscia richardsonae Ammothea hilgendorfi Lophopanopeus leucomanus Amphiodia occidentalis Melita californica Anatanais normani Metacarcinus magister Balanus amphitrite Nymphopsis spinosissima Balanus glandula Oedignathus inermis Balanus nubilus Oligochinus lighti Cancer productus Pachygrapsus crassipes Caprella anomala hirsutiusculus Caprella californica Pagurus samuelis Chthamalus dalli Paracerceis cordata Cirolana harfordi Parallorchestes ochotensis Elasmopus serricatus Paraxanthia taylori Exosphaeroma inornata 2014] INTERTIDAL FARALLON 273

APPENDIX 2. Continued. APPENDIX 2. Continued. Polycheria osborni Chlorostoma funebralis Porcellio americanus Corolla spectabilis Pugettia gracilis giganteum Pugettia producta adunca Romaleon antennarium Crepidula perforans Scyra acutifrons lingulata Cryptochiton stelleri Tetraclita rubescens Cryptomya californica CNIDARIA Cyanoplax dentiens Allopora porphyra Cymakra aspera Anthopleura elegantissima Diodora aspera Anthopleura sola Diplodonta orbella Anthopleura xanthogrammica Dirona picta Aurelia aurita Epitonium tinctum Balanophyllia elegans Flabellina trilineata Corynactis californica Granulina margaritula Epiactis prolifera Haliotis cracherodii Obelia sp. Haliotis rufescens Stylantheca porphyra Hermissenda crassicornis Symplectoscyphus turgidus Hiatella arctica Tethya aurantia Hipponix craniodes Tubularia crocea Irus lamellifer Urticina lofotensis Ischnochiton regularis tunicata ECHINODERMATA Amphiodia occidentalis Kellia laperousii Amphipholis squamata Lacuna cistula Dermasterias imbricata Lacuna marmorata Lacuna porrecta Lacuna unifasciata Leptasterias pusilla Lasaea subviridis Loxorhyncus crispatus Lirobittium purpureum Ophiopholis aculeata Littorina keenae Ophiothrix spiculata Littorina scutulata giganteus Littorina sitkana asmi Pycnogonum stearnsi Lottia digitalis Pycnopodia helianthoides Lottia gigantea Strongylocentrotus droebachiensis Lottia insessa Strongylocentrotus franciscanus Lottia instabilis Strongylocentrotus purpuratus Lottia limatula Lottia pelta ENTOPROCTA Lottia persona Barentsia benedeni Lottia scabra Lottia scutum Flustrellidra corniculata Lottia strigatella Integripelta bilabiata Lottia triangularis Megatebennus bimaculatus mitra Milneria minima Alia tuberosa Modiolus capax Modiolus carpenti Amphissa versicolor ciliata Anisodoris nobilis Mopalia muscosa Balcis thersites Musculus pygmaeus Barleeia haliotiphila Mytilus californianus Barleeia subtenuis Nassarius mendicus Berthella californica Nuttallina californica Bittium eschrichtii Ocinebrina atropurpurea luteomarginata Ocinebrina interfossa Cadlina modesta Ocinebrina luridaOctopus dofleini annulatum Octopus dofleini Calliostoma canaliculatum Octopus rubescens Odostomia sp. Chama arcana Okenia rosacea Chlorostoma brunnea Onchidella borealis 274 MONOGRAPHS OF THE WESTERN NORTH AMERICAN NATURALIST [Volume 7

APPENDIX 4. South Farallon Islands intertidal algae APPENDIX 2. Continued. species inventory, as of February 2011.

Opalia wroblewskyi CHLOROPHYTA Placiphorella velata Acrosiphonia coalita Penitella conradi Blidingia minima var. vexata Penitella turnerae Bryopsis corticulans Petricola carditoides Cladophora columbiana Philobrya setosa Cladophora graminea Protothaca staminea Codium fragile Rostanga pulchra Codium setchellii lineata Derbesia marina Tonicella lokii Endophyton ramosum Transennella tantilla Entocladia viridis Trimusculus reticulatus Prasiola meridionalis Triopha catalinae Ulothrix flacca Triopha maculata Ulva californica PORIFERA Ulva clathrata Anaata spongigartina Ulva compressa Antho lithophoenix Ulva conglobata Aplysilla glacialis Ulva flexuosa Aplysilla polyraphis Ulva intestinalis Axocielita originalis Ulva lactuca Clathria sp. Ulva lobata Geodia mesotriaence Ulva taeniata Halichondria panicea Urospora sp. Haliclona sp. OCHROPHYTA Higginsia sp. Alaria marginata Leucandra heathi Analipus japonicus Leucilla nuttingi Colpomenia peregrina Leucosolenia eleanor Compsonema serpens Lissodendoryx topsenti Costaria costata Mycale psila Desmarestia herbacea Myxilla incrustans Desmarestia munda Ophlitaspongia pennata Dictyoneurum californicum Scypha sp. Egregia menziesii Stelletta clarella Hinksia sandriana Suberites sp. Laminaria ephemera Tedania gurjanovae Laminaria setchellii Tethya aurantium Laminaria sinclairii Leathesia difformis SIPUNCULA Phascolosoma agassizii Melanosiphon intestinalis Petalonia fascia CHORDATA TUNICATA Petrospongium rugosum Aplidium californicum Pterygophora californica Archidistoma eudistoma Pylaiella sp. Archidistoma ritteri Ralfsia sp. Cystodytes lobatus Scytosiphon dotyii Didemnum carnulentum Scytosiphon lomentaria Pycnoclayella stanleyi Spongonema tomentosum Ritterella aequalisphonis Stephanocystis osmundacea Styela montereyensis RHODOPHYTA Acrochaetium sp. Ahnfeltiopsis leptophylla Ahnfeltiopsis linearis Anotrichium furcellatum APPENDIX 3. South Farallon Islands intertidal fish Antithamnion dendroidum species inventory, as of February 2011. Audouinella subimmersa Bangia sp. CHORDATA (FISH) Bornetia californica Clinocottus acuticeps Bossiella dichotoma Clinocottus embryum Bossiella plumosa Clinocottus recalvus Bossiella schmittii Gobiesox maeandricus Branchioglossum bipinnatifidum Oligocottus maculosus Branchioglossum undulatum Oligocottus snyderi Calliarthron tuberculosum Xiphister mucosus Callithamnion biseriatum 2014] INTERTIDAL FARALLON 275

APPENDIX 4. Continued. APPENDIX 4. Continued. Callithamnion pikeanum Mazzaella parksii Callophyllis crenulata Mazzaella rosea Callophyllis flabellulata Mazzaella splendens Callophyllis heanophylla Mazzaella volans Callophyllis linearis Melobesia marginata Callophyllis obtusifolia Melobesia mediocris Callophyllis pinnata Membranoptera dimorpha Callophyllis violacea Mesophyllum lamellatum Centroceras clavulatum Microcladia borealis Ceramium gardneri Microcladia coulteri Ceramium pacificum Myriogramme spectabilis Chondracanthus canaliculatus Myriogramme variegata Chondracanthus corymbiferus Neogastroclonium subarticulatum Chondracanthus exasperatus Neoptilota densa Chondracanthus harveyanus Neoptilota hypnoides Chondracanthus spinosus Neorhodomela larix Clathromorphum parcum Nienburgia andersoniana Constantinea simplex Odonthalia floccosa Corallina chilensis Opuntiella californica Corallina vancouveriensis Osmundea spectabilis Corallophila eatonianum Peyssonnelia sp. Cryptopleura corallinara Peyssonneliopsis epiphytica Cryptopleura lobulifera Phycodrys setchellii Cryptopleura ruprechtiana Pikea californica Cryptopleura violacea Pikea pinnata Cumagloia andersonii Pleonosporium vancouverianum Delesseria decipiens Plocamium pacificum Dilsea californica Plocamium violaceum Endocladia muricata Polyneura latissima Erythrophyllum delesserioides Polysiphonia hendryi Erythrotrichia carnea Polysiphonia pacifica Farlowia compressa Porphyra perforatarionitis lanceolata Farlowia conferta Prionitis lanceolata Farlowia mollis Prionitis linearis Faucheocolax attenuata Prionitis sternbergii Gelidium coulteri Pseudolithophyllum neofarlowii Gelidium robustum Pterochondria woodii Gloiocladia laciniata Pterocladia caloglossoides Goniotrichopsis sublittoralis Pterosiphonia baileyi Gracilariophila oryzoides Pterosiphonia bipinnata Gracilariopsis andersonii Pterosiphonia dendroidea Grateloupia californica Pterothamnion villosum Grateloupia filicina Ptilota filicina Griffithsia pacifica Ptilothamnionopsis lejolisea Gymnogongrus Pugetia fragilissima Halosaccion glandiforme Pyropia gardneri Halymenia schizymenioides Pyropia lanceolata Herposiphonia parva Pyropia nereocystis Herposiphonia plumula Pyropia perforata Hildenbrandia occidentalis Rhodochorton purpureum Hymenena flabelligera Rhodymenia californica Hymenena multiloba Rhodymenia callophyllidoides Janczewskia gardneri Rhodymenia pacifica Leachiella pacifica Rhodymeniocolax botryoides Lithophyllum dispar Sahlingia subintegra Lithothrix aspergillum Sarcodiotheca gaudichaudii Maripelta rotata Schimmelmannia plumosa Mastocarpus jardinii Scinaia confusa Mastocarpus papillatus Smithora naiadum Mazzaella affinis Stenogramma interrupta Mazzaella californica Stylonema alsidii Mazzaella flaccida Tiffaniella snyderae Mazzaella leptorhynchos Weeksia reticulata Mazzaella linearis TRACHEOPHYTA Mazzaella oregona Phyllospadix scouleri