I OCS Study

MMS 96-0009

I

Mussel Recoveryand Species II

Dynamicsat FourCalifornia

II oc IntertidalSites

I 1992 Data Report

I Prepared by:

I Minerals Management Service

Maurice Hill

Lynnette Vesco Mary Elaine Dunaway

Mike McCrary

I Mark Pierson

and

I Kinnetic Laboratories. Inc.

I Eric Nigg

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l MMS Reference No. PC 94-1

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i U.S. Department of the Interior I MineralsManagemenStervice

PacificOCSRegion May 1996

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It is suggested that this report be cited as follows:

Minerals Management Service and Kinnetic Laboratories, Inc. 1996. Mussel recovery and I

species dynamics at four California rocky intertidal sites. 1992 data report. U.S.

Department of the Interior, Minerals Management Service, Pacific OCS Region. OCS I

Study MMS 96-0009. 151 pp.

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I PROJECT ORGANIZATION

CONTRACTING OFFICER'S TECHNICAL REPRESENTATIVE Fred Piltz, Chief, Environmental Studies Section

I PROJECT/REPORT TEAM

MaryElaine Dunaway

Maurice Hill

I Mike McCrary

Eric Nigg

Ma Lynnette rk Pierson Vesco

I FIELD Mary SURVEY Elaine Dunaway TEAM

Michael Foster

I Bo Maurice b GillardHill

Mike MeCrary

I Eric Nigg Sallie Nigg

Mark Pierson

I Diana Stellar Lyrmette Vesco

I PROJECT SUPPORT

Mertis Baffoe-Harding

Debbie Eidson

I Nollie Gildow-Owens

Joann Golden

i Tammy Janic_ MMill adiseron

Rochelle Williams-Hooks

,!i MMS ENVIRONMENTAL STUDIES PROGRAM LIAISON

Tom Ahlfeld

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I ACKNOWLEDGMENTS

This study was funded by the MMS Pacific OCS Regional Office in Camarillo, California. The

I MMS management Intertidal team gratefully acknowledges the support and encouragement of our in this endeavor.

I We wish to thank the many scientists at Kinnetic Laboratories, Inc., for their continued interest in the study and for their assistance in this effort. In particular,we would like to acknowledge

Laurie Kiguchi for her personal time and attention, JohnToal for the field preparation efforts,

I and Kathleen Dorsey and Peter Wilde for their help in providing needed information and

computer programs for the report.

I We appreciate the participation of Dr. Robert Gillard (MMS, Gulf of Mexico Regional Office) in I

the project initiation and field data collection.

I We want to thank Dr. Michael S. Foster at Moss Landing Marine Laboratories for generously

providing transportation, skippers, and field assistance at Pescadero Rocks. We also want to

thank organisms. Dr. Steve Wenacknowledge N. Murray fother proHearst vidingRausnchwithandcurrent Sea Ranch taxonoAssocia mic nomtionsenclfor atureproviding on intertidal access

to the sites.

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I PREFACE

This is an interim report for a study of mussel recovery and species dynamics at four California

I rocky Mineralsintertidal Management sites. Conducted by Kinnetic Laboratories, Inc. (KLI), and funded by the Service (MMS), the initial experimental field study began in spring 1985

and continued through spring 1991. The initial field study included six sites along the central

I and northern California coast. In 1992, MMS decided to continue the work started by KLI through an in-house study and establishment of the MMS Intertidal (MINT) team. Four of the

original six sites have been continued by MMS. The study methods of the original study have

I been retained by the MINT team, and close coordination with the original KLI team continues.

In 1994, the MMS Environmental Studies Program officially awarded a contract to the MINT

i team for this in-house study. This interim report presents the results from the fail 1992 sampling, t

the first year of sampling by the MINT team. The report presents a limited statistical analysis

and visual comparison of the 1992 data. The next interim report will include data collected

I during fall 1994 and will present a broader statistical analysis of both the 1992 and 1994 data sets.

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I TABLE OF CONTENTS

PROJECT ORGANIZATION ................................................... iii

i ACKNOWLEDGMENTS ....................................................... v

I PREFACE ................................................................. vii

EXECUTIVE SUMMARY ................................................... xvii

! I. INTRODUCTION .......................................................... 1

I II. METHODS ............................................................... 4

A. Survey Sites ........................................................... 4

i B. Field Methods and Analyses ............................................... 9

Ill. RESULTS ............................................................... 15

i A. 1. Kibesillah Mytilus Assemblage Hill ......................................................... ................................................... 15

2. Endocladia/Mastocarpus Assemblage ..................................... 27

I B. Sea 1. Mytilus Ranch Assemblage ............................................................. ................................................... 32

2. Endocladia/Mastocarpus Assemblage ..................................... 41

I C. Pescadero Rocks ........................................................ 46 1. Mytilus Assemblage ................................................... 46

2. EndocIadia/Mastocarpus Assemblage ..................................... 56

I D. Point Sierra Nevada ..................................................... 61

1. Mytilus Assemblage ................................................... 61

2. Endocladia/Mastocarpus Assemblage ..................................... 71

I IV. DISCUSSION ........................................................... 75

A. Comparison of the Mytilus Assemblage at the Four Study Sites ................... 75

I B. Comparison of the Endocladia/Mastocarpus Assemblage at the Four Study Sites ..... 85

C. Conclusion ............................................................ 89

I V. REFERENC_ ........................................................... 90

I VI. APPENDIX ............................................................. 93

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I LIST OF FIGURF_

1. Location of the four study sites ............................................ 6

I 2. Recovery of spring- and fall-cleared plots in the Mytilus

assemblage at Kibesillah Hill ............................................. 16

I 3. Similarity of the control plots in the Endocladia/Mastocarpus

i assemblage at Kibesillah Hill ............................................. 31

4. Recovery of spring- and fall-cleated plots in the Mytilus

i assemblage at Sea Ranch ................................................ 33

5. Similarity of the control plots in the Endocladia/Mastocarpus

i assemblage at Sea Ranch ................................................. 45

6. Recovery of spring- and fall-cleared plots in the MytiIus

I assemblage at Pescadero Rocks 47

7. Similarity of the control plots in the EndocIadia/Mastocarpus

I assemblage at Pescadero Rocks ........................................... 60

8. Recovery of spring- and fall-cleared plots in the Mytilus

I assemblage at Point Sierra Nevada ......................................... 62

9. Similarity of the control plots in the EndocIadia/Mastocarpus

I assemblage at Point Sierra Nevada 74

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I LIST OF TABLES

1. Summary of site characteristics for the Mytilus assemblage ...................... 7

I 2. Summary of site characteristics for the Endocladia/Mastocarpus assemblage ......... 8

I 3. Recent changes to macrophyte and macroinvertebrate nomenclature for

taxa observed in this study ................................................ 13

I Similarity (percent) MytiIus assemblage plots to plots,

4. of the cleared the control

the percent cleared plots have recovered, and the similarity of the least similar

control plots during fall 1992 ............................................. 17

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5. Macrophyte, macroinvertebrate, and substratum abundances in the Mytilus

i assemblage control plots at KibesiUah Hill during fall 1992 ..................... 18

6. Macrophyte, macroinvertebrate, and substratumabundances in the Mytilus

I assemblage cleared plots at Kibesillah Hill during fall 1992 21

7. Summary of Mytilus cover, density, and recovery rate during fall 1992 ............ 25

I 8. Macrophyte, macroinvertebrate, and substratum abundances in the

Endocladia/Mastocarpus assemblage control plots at Kibesillah Hill

I during fall 1992 ....................................................... 28

9. Macrophyte, macroinvertebrate, and substratum abundances in the MytiIus

I assemblage control plots at Sea Ranch during fall 1992 34

10. Macrophyte, maeroinvertebrate, and substratum abundances in the Mytilus

I cleared Sea Ranch fall 1992 37 assemblage plots at during

11. Macrophyte, maeroinvertebrate, and substratum abundances in the

I Endocladia/Mastocarpus assemblage control plots at Sea Ranch

during fall 1992 ....................................................... 42

I 12. Macrophyte, maeroinvertcbrate, and substratum abundances in the Mytilus

assemblage control plots at Peseadero Rocks during fall 1992 ................... 48

I 13. Macrophyte, macroinvertebrate, and substratum abundances in the Mytilus

assemblage cleared plots at Pescadero Rocks during fall 1992 ................... 51

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LIST OF TABLES (Continued) I

14. Macrophyte, macroinvertebrate, and substratum abundances in the

Endocladia/Mastocarpus assemblage control plots at Pescadero Rocks 1

during fall 1992 ....................................................... 57 m

15. Macrophyte, macroinvertebrate, and substratum abundances in the Mytilus 1

assemblage control plots at Point Sierra Nevada during fall 1992 ................ 63

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16. Macrophyte, macroinvertebrate, and substratum abundances in the Mytilus I

assemblage cleared plots at Point Sierra Nevada during fall 1992 ................ 66

17. Macrophyte, macroinvertebrate, and substratum abundances in the I

Endocladia/Mastocarpus assemblage control plots at Point Sierra Nevada

during fall 1992 ....................................................... 72 1

18. The more abundant (>2 percent cover) taxa in the Mytilus assemblage

control plots at the four study sites during fall 1992 76 1Illlll

19. Species richness, biotic cover, and substratum abundance in the Mytilus

assemblage control plots at the four study sites during fall 1992 ................. 76 I

20. The more abundant (>3/0.1875 m2) grazers in the Mytilus assemblage

control plots at the four study sites during fall 1992 ........................... 78 I

21. Species richness, biotic cover, and substratum abundance in the Mytilus I

assemblage spring-cleared plots at the four study sites during fall 1992 ............ 80 1

22. Mytilus cover (percent) in spring- and fall-cleared plots observed •

at the four study sites during spring 1991 and fall 1992 ........................ 81 1

23. Mytilus density (no.tO.1875 ms) in spring- and fall-cleared plots observed •

at the four study sites during spring 1991 and fall 1992 ........................ 82 I

24. Mytilus assemblage recovery rates at the four study sites during spring 1991 ll

and fall 1992 ......................................................... 82

25. Species richness, biotic cover, and substratum abundance in the Mytilus I

assemblage fall-cleared plots at the four study sites during fall 1992 .............. 83

26. Species richness, biotic cover, and substratum abundance in the I Endocladia/Mastocarpus assemblage control plots at the four study sites

during fall 1992 ....................................................... 86 I

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I LIST OF TABLES (Continued)

27. The more abundant (>2 percent cover) taxa in the Endocladia/Mastocarpus

I assemblage control plots at the four study sites during fall 1992 ................. 86

28. The more abundant (>3/0.1875m 2) grazers in the Endocladia/Mastocarpus

I assemblage control plots at the four study sites during fail 1992 ................. 88

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I EXECUTIVE SUMMARY

This report presents the interim results of a long-term study of rocky intertidal communities in

I Calif Laborato ornia. From 1985 to 1991, the initial phase of this study was conducted by Kinnetic ries, Inc. (KLI), in association with the Moss Landing Marine Laboratories, the

University of California, Santa Cruz, and TENERA Corporation under contract from the

I Minerals Management Service (MMS). Since 1992, biologists from the Pacific OCS Region of the MMS and one of the KLI investigators have continued the study at four of the original six

sites.

I MMS's primary goals in continuing this study were to answer the following questions:

I long a assemblage to recover a major (complete How does mussel take from disturbance

clearing)?

I • What significant changes occur over time in undisturbed mussel and algal assemblages?

i Tcalifornianus) o answer theseandquaesredtions, algaltwoasassem semblage blage(sEndocladia were studiemurica d: a mta/Mas ussel tocarpus assemblagepapi (Mytilus Uatus). Since

the more abundant organisms in these assemblages are persistent and some are slow-growing,

I the estimate se assembl howalong ges citotakes uld incforur alomussel ng-termassemblage impacts fotollowing recovera distur frombaance majorsuchdisturbance, as an oil sall pill. To

living material growing in designated plots on the rocky intertidal shoreline was removed in

I spring 1985 or fall 1985. Recovery of the cleated plots was determined by comparing them to undisturbed plots within the same assemblages. Additionally, control plots were studied in each

assemblage to study changes in undisturbed mussel and algal assemblages.

I Although the complete clearance of biota from the rocky substrate does not exactly mimic the

effects of an oil spill, it does allow us to determine approximately how long recovery from an oil

I spill would take at the four sites, particularly if complete removal were to result from a cleanup

operation (e.g., steam cleaning). By using complete clearance, we have eliminated many

variables that would occur ff experimental oiling was attempted. However, there are some

I drawbacks to this approach, spills generally do not result complete biota,

Oil in the removal of

particularly of macrophytes. It is possible that partial remains of macrophytes may regrow or

i • affect the colonization of other species. Also, oil spills may cover much larger areas than those

i II chosen for analysis in this study. This toocould affect both successional patterns and recovery.

Thus, recovery following an oil spill could actually take a shorter or longer period of time than

i recovery from the total clearance approach used in this study.

Results from fall 1992 showed that, after 71⁄2 years, none ofthe mussel assemblage plots that

I were rate. cleared In fall 1992, by KLIthehadcleared recovered plots were compmore letely.similar However, to therecovery control isplots continuing than theyatwere a veryduring slow

the last survey by KLI, and mussel abundance was greater. Although it is not possible at this

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time to determine how long recovery will actually take, current trends indicate that complete I

recovery of the spring- and fall-cleared mussel plots at all of the sites will probably take several

more years. The MMS plans to continue to monitor these plots every 2 years until recovery

Occurs. I

The study of undisturbed mussel and algal assemblages indicates that, although these I

assemblages persist and are usually stable over time, changes can occur due to natural or human

disturbances. For example, mussel abundance in the control plots increased at one site and 

dabundance ecreased aatt anthree otherofsitthee. fAourdditio stesnallandy, the therealgal hasassemblage been a general at onedownward site was treconsiderably nd in algal poorer I

in species richness and algal abundance compared to the other sites. These trends will be closely

monitored every 2 years to determine whether they continue. I

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I I. INTRODUCTION

Because of its concern for the susceptibility of the California coastto impacts from an offshore

I oil spill, the M_MSin the late 1970's developed a two-stage plan to study rocky intertidal

communities along the coast. The first phase involved the characterization of coastal habitats

and evaluation of their sensitivity to oil spills. The second phase of the study was titled

I "Successional and Seasonal Variation of the Central California

and Northem Rocky Intertidal

Communities."

I The latter study was designed to: 1) describe seasonal and long-term variation in rocky intertidal

community structure; 2) determine the responses of these communities to natural and

i anlatitudinal thropogenvaicriadtiosturb n; 3)ance correl s andateclife orrelhate istorytheinformation se responses awith nd oilseaso toxincal, ity succ dataewith ssionfial,eldanddata

obtained from the study; 4) compare the results of this study with other relevant studies; and 5)

I provide background datafor designing future oiling experiments or monitoring programs.

To conduct the study, the MMS contracted with Kinnetic Laboratories, Inc. (KLI), of Santa Cruz,

I California. In undertaking the study, KLI formulated several hypotheses and questions that could be addressed with statistically rigorous sampling and replicable experiments:

I 1) Do species composition and abundance vary with season and latitude (between Oregon and Point Conception)?

I 2) How long does a disturbed (completely cleared) area take to recover? How are the time

and pattern of recovery affected by type of assemblage disturbed, site, latitude, and time

i of year in which disturbance took place?

Although the complete clearance of biota from the rocky substrate does not exactly mimic the

i eff spiecll tswould of antake oil spill at th,eitfour doessites allo,wpart usicul to dete arlyrmine if comapproximate plete removally were how ltoongresreco ult fro verym faromcleananupoil

operation (e.g., steam cleaning). By using complete clearance, we have eliminated many

I vdrawbacks ariables thatotthis wouldapproach. occur if Oi expel spil rimlsentagenl eoffi rallngy dwoasnoatt t remp sulteind.theHocwoever, mpletethereremovarealsoofmebiota,

particularly of macrophytes. It is possible thatpartial remains of macrophytes may regrow or

I affect the colonization of other species. Also, oil spills may cover much larger areasthan those chosen for analysis in this study. This too could affect both successional patterns and recovery.

Thus, recovery following an oil spill could actually take a shorter or longer period of time than

I recovery from the total clearance approach used in this study.

The project began in late 1983. The tasks included a literature review, development of an initial

I field survey plan, a preliminary field survey, and a methods comparison study. The initial field

survey plan presented the experimental design for a long-term field study to address the questions

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presented above. Field sampling was conducted biannually (spring and fall) from spring 1985

through spring 1991, except in 1990.

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Six sites along the central and northern California coast were surveyed during the field study 1

(Kinnetic Laboratories, Inc., 1986). At each site, two assemblages were surveyed: a high

intertidal, macrophyte-dominated assemblage (EndocladialMastocarpus); and a mid-intertidal, •

macroinvertebrate-dominated assemblage (Mytilus). Experimental plots were cleared in each 1

assemblage in spring 1985 and fall 1985. Since an experimental application ofoil was

impracticable, experimental plots were cleared mechanically by scraping and heating the •

substratum until no visible organic matter remained. This method was reproducible and resulted 1

in a consistent, comparable degree of clearing at all sites.

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The MMS-fimded central and northern California intertidal recovery study conducted by KLI I

ended in the spring of 1991 after 6 years of field effort. The results were presented in a final

report for the study (Kinnetic Laboratories, Inc., 1992). A summary of their f'mdings is presented •

below. II

Recovery rates for cleated plots in the EndocladialMastocarpus assemblage varied from [I

complete recovery in 1 year for all spring-cleared plots at one site to incomplete recovery of all m

fall-cleared plots at another site at the end of 6 years. Recovery rates were significantly different 1

among sites and seasons of clearing, but there was no statistically significant relationship II

between recovery and latitude.

Recovery rates for cleared plots in the MyffIus assemblage were very low, with a very low I

abundance (<20 percent cover) of mussels overall and no plot completely recovered after 6 years.

Because the literature indicates that recovery may require 10 years or more (Chan and Molina, •

1969; Cimberg, 1975; Vesco and Gillard, 1980; Paine and Levin, 1981; Kinnetic Laboratories, I

Inc., 1992), the mussel populations might have been expected to have reached the halfway point

in 6 years if recovery were a linear response with time. The marked lack of observed recovery •

raised questions of when, or if, the cleared mussel plots would return to their original,

undisturbed state, or to states comparable to adjacent control plots. Alternatively, the plots could

stabilize as another community type. The mussel recruitment occurring at all stations (Kinnetic •

Laboratories, Inc., 1992) suggests they eventually will become similar to the surrounding mussel

assemblages, but recovery is estimated to be years away at most sites.

Although the study was well designed and answered many important questions, key questions 1

remain unanswered. In particular, the questions of whether the as yet urtrecovered mussel sites

would return to mussel assemblages and, if this occurred, how long the recovery would take were 1

unknown. Related questions regarding recovery patterns and sequences also need to be

addressed. Information collected from the continuation of the long-term study will further our m

understanding of the subtle differences between habitats, population dynamics, and general II

recovery processes of this important mussel assemblage over a broad geographic area.

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I In their review of the Outer Continental Shelf (OCS) Environmental Studies Program, the National Research Council (NRC) highlighted the need for studies to determine recovery rates of

faunal assemblages and the need to focus on long-term studies of populations and processes. The

NRC stated that "recovery rates of faunal elements to tend to be report subsequent damage

overestimated. In many cases, the studies required for meaningful estimates of recovery rates

have not been done" (NRC, 1989). Further, the NRC reported that "[i]nformation collected over

I several years should be used in decision-making to provide insights on trends and variations in

populations and processes." This study addresses both of these program needs.

I Although many questions will be addressed in the current study, by continuing the work begun

by KLI, ourprimary goals remain similar to those of the original KLI study, namely to answer

I the following questions:

1) How long does a mussel assemblage take to recover from a major disturbance (complete

I cleating)? and

2) What significant changes occur over time in undisturbed Mytilus and

i EndocladialMastocarpus assemblages?

This Interim Report, which presents a limited statistical analysis and visual comparison of the

I data collected during fall 1992, addresses only the f'trst question. A quantitative treatment of the

second question will require a more rigorous statistical treatment of the data. The next Interim

Report will include data collected during fall 1994 and will present a broader statistical analysis

I of both the 1992 and 1994 data sets,

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II. METHODS I

A. Survey Sites •

Rocky shores exhibit high levels of community diversity and complexity, and variation among

locations on the central and northern California coast can be great (Dayton, 1971; Suchanek, •

1979; Kanter, 1980; Paine and Levin, 1981). The original KLI study design required that I

multiple sites with similar biological characteristics be selected over a wide geographic range,

which made it necessary to evaluate the attributes of a large number of sites. I

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Kinnetic Laboratories, Inc. (1992), made a preliminary survey of 20 sites along the California

coast between Point Conception and the Oregon border to locate sites with consistently occurring 1

assemblages of intertidal macroorganisms. From these 20, 6 sites were chosen for the studies of

seasonal variation and succession. The selection criteria included an even distribution of sites

along the coast, sufficient area within the assemblages at a given site to set up experimental and I

control plots, and sufficient geographic range among the sites to provide a latitudinal gradient

without substantial loss of biological comparability.

Biological assemblages were chosen based on latitudinal distribution, occurrence at all sites,

intertidal heights, high-percent cover at pre_ survey sites, persistence and slew growth of II

dominant species, and the extent of available literature databases regardhtg pertinent [[

assemblages. Two biological assemblages were selected. The fast was a typically high-intertidal

assemblage dominated by the tufted red alga Endocladia muricata and the fleshy red alga II

Mastocarpus papiUatus, which occurred in the upper intertidal areas at all sites (see Glynn, |

1965). The second was the assemblage dominated by the mussel Mytilus californianus, which

formed beds in more seaward areas of all sites (Dayton, 1971; Suchanek, 1979; Kanter, 1980; •

Paine and Levin, 1981). l

The six study sites were distributed along the California coast from Mendocino County south to •

San I.,uis Obispo County, over a distance of approximately 400 miles (Kinnetic Laboratories,

Inc., 1992). From north to south, the sites were: Kibesillah Hill in Mendocino County, Sea

Ranch in Sonoma County, Bolinas Point in Matin County, Peseadero Rocks in Monterey County, I!

Point Sierra Nevada in San Luls Obispo County, and Diablo Canyon in San Luis Obispo County.

In spite of attempts to select sites that were similar, there was much variability among sites in I

both assemblages. Among the factors that varied among sites were the degree of solar insolation m

and amount of coastal upweUing, estimates of which were both greater at the southern sites; ma

small- and large-scale topography and substratum composition; and the relative abundance of 1

some of the dominant macroorganisms. Some species showed geographic differences in

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distribution, size, or abundance among sites. The six sites are described in detail in the study I

final report (Kinnetic Laboratories, Inc., 1992).

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I For the current study, we decided that, given available personnel within the MMS's Pacific OCS Region, only four of the six sites surveyed from 1985 to 1991 during the KLI study could be

monitored effectively. The sites selected include those at Kibesillah Hill, Sea Ranch, Pescadero

I Rocks, and Point Sierra Nevada (Figure 1). The sites were selected to retain broad geographic

coverage and varying degrees of observed community recovery.

I The following paragraphs briefly describe each of the study sites (Kinnetic Laboratories, Inc.,

1992). Average elevations for plots are given as meters above mean lower low water (MLLW)

i (Tables 1 and 2):

]_fi_a.J:lJll. The Kibesillah Hill site is located approximately 10 miles north of Fort Bragg in

i Me siltstone ndocinano dCoun cut byty (Figure deep cha1)nne. The ls. Astuverage dy ploelevation ts are situated of theonMytitus slopingassemblage benches coplots mposised+1.9 of hm; ard

that of the EndocladialMastocarpus assemblage plots is +1.7 m. Topographic relief is moderate

I timpacts o high, watitthi h sa,slightl the moysteleva nortted, herlyfiasite, t areacantobeseaqwuard ite sevwheere. re the mussel plots are located. Wave

I Sea ILaneh. The Sea Ranch site is located approximately 20 miles south of Point Arena on the Sonoma County coast (Figure 1). The plots are situated on a hard sandstone bench composed of

tilted sedimentary strata. Average elevation of the Mytilus assemblage plots is +2.1 m; that of

i I the EndocladialMastocarpus assemblage plots is +1.3 m. The strata slope slightly toward shore, forming ridges with steep seaward faces and giving the area the highest topographic relief of any

site. These steep seaward faces and offshore rocks moderate the effects of incoming waves on

I the site.

study

Pescadero Rocks. The Peseadero Rocks study site is located on a small offshore island within

I Stillwater Cove, Carmel Bay, in Monterey County (Figure 1). The study plots ate located on the

western shore of a gently sloping bench that is composed of a hard conglomerate and sandstone.

I Ave EndocladialMastocarpus rage elevation of the Mytilus assemblass ageembplots lageis plo +1.9ts im. s +Wave 1.4 m;impact that of the on the site is highly variable

since it depends on the direction and intensity of the waves. During our first visit to the site in

I Fauncovere ll 1992d,.thAt e woathveeractimes tion,hithtteingwater the iisslanveryd wstasill,soassitmpl rongiedthabyt ththeeMyname tilusofplothets coweve. re not

I PPoint oint Sierra Pi Nevada. The Point Sierra Nevada site is located approximately 5 miles north of the edras Blaneas lighthouse in San Luis Obispo County (Figure 1). The study plots are

situated on a relatively fiat bench composed of hard conglomerate sandstone. Average elevation

I of the Mytilus assemblage plots is +1.4 m; that of the EndocladialMastocarpus assemblage plots is + 1.9 m. Vertical relief is low compared to the other sites. Although the point is exposed to

westerly swells, the effects of waves on the plots are moderated by offshore rocks and a shallowI sloped nearshore bottom.

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o'o,....... / '-......... ' !

/ L o 50 loo I

Cape _EUR_A MILES I

40°- Mendocino _ i I NEVADA

___Ft. ?'_ \\\ \ \ I

380-- Reye:mr_n_ _._ _

8an Francisco'_ _A _1FRANCISCO I

t"_k 8ante Cruz

_,_ NTA CRUZ I

PESCADE"='IllR='-O \ _, I

Pt. Sur

36 °- Monterey T I

8an Luis

PACIFIC OCEAN Pt. Buchon Obispo I

18enta Barbara

Pt. Conceptio Venture AngLoseles I

SANTA

34 °- BARBARA n

Figure l. Location of the four study sites.

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I Table 1. Summary of site characteristics for the Mytilus assemblage.

I Site Tidal Height _ Substratum _

I (m)

I Kibesillah +1.9 Hcarbo ardnasilttses;tonegenand tly sloping

Hill platform extending seaward

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I Hard sandstone; broad,flat

Sea Ranch +2.1 ridges with steep seaward

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I PesRocadero cks +1.4 ben sadst ch one with; gaenbrupt tly sseaward loping

edge

I

i Point Sierra +1.4 Hsanarddstone; conglomera moderatetelyand

Nevada sloping bench with irregular

i topography, abrupt edge

I _Informationisfrom KinnetiLcaboratorieIs,nc.(1992).

2Mean ofcente_ofplotsaboveMLLW (n=10).

I

I

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7

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Table 2. Summary of site characteristics for the EndocladialMastocarpus assemblage. !

Site Tidal Height 1_ Substratum _ !

(m) I

Kibesillah + 1.7 Silt carbona stonete-and hard; I

Hill gently sloping platform

I

Lithic sandstone-hard; I

Sea Ranch +1.3 broad, flat ridges

wrocks ith higher offshore i

I

Conglomerate and

PescRocks adero +1.9 ssloping andstone- rockhard; waltsteeply I

I

Point Sierra + 1.9 Cong sandsltone-har omerated;andbroken I

Nevada platform with low offshore

_ks [

t InformationisfromKinneticLaboratories, Inc.(1992). I

2Meanof centerof plotsaboveMLLW(n=10). I

I

I

I

I
I As recommended by Kinnetic Laboratories, Inc., (1992), we decided to focus the current study on the continued recovery of the Mytilus assemblage. We also decided that, given the relatively

high degree of recovery of the EndocladialMastocarpus assemblage at the four sites selected for

I this study and the limitations on available personnel, we would only monitor the control plots in

those assemblages. Thus, at each site both control and cleared plots were sampled in the Mytilus

assemblage, whereas only control plots were sampled in the EndocladialMastocarpus

I assemblage.

I B. Field Methods and Analyses

The methods used for selecting both control and study plots and for clearing study plots were

I deach escribofetdheinfouther KLI sites study will befinsal amrpepoledrtbienn (Kinniaelltiyc duLabo ringratotheries, fall.InToc., dat 1992e,)the . Insites the cur haverenbteestud n y,

sampled twice since MMS personnel began monitoring: in October-November 1992, and in

I November-December 1994. The results of the 1992 survey are discussed in this report.

Five to six MMS biologists participated in each sampling period. In addition, one of the original

I KLI investigators, Eric Nigg, remained involved with this study, functioning as a research team

member and providing guidance to ensure consistency in research methods.

I At each site, I2 plots were sampled during each visit. In the Mytilus assemblage, three springcleared plots, three fall-cleared plots, and three of the four possible control plots were sampled.

In the EndocladialMastocarpus assemblage, three of the four control plots were sampled. Four

I control established each site to in the event that

plots were at provide backup one was drastically

disturbed during the study. All have been sampled on a rotating basis, but only three during any

one sampling period. I

• Each plot was a 1 x 2-m rectangle, which was delineated by a frame made of white PVC tubing

i (Inc., shown1992), in thtoe cminimiz over phoe toedgrgape effec hs). tsAsindisc the uscleare sed dinplthoetsKLI due fprim inal areport rily to(Kin grazneers, tie only Laborat theori cees, nter

0.5 x 1.5-m area of each plot was sampled, leaving a 0.25-m border. This was also done in the

I control 0.25 m p(0.0lots625formcons 2)eist ach. encThr y. eeTheofcentral these quaraedra awtsaswfuerrether chosen divideatd ranintodom12inquadrats each plot of 0for.25each x

sampling period and sampled for percent cover of all macroorganlsms and the density of motile

I maeroinvertebrates. This provided a total sample area of 0.1875 m2 in each plot, distributed randomly through time.

I The macroorganisms observed included both macrophytes (multiceHular algae large enough to be visible to the unaided eye) and sessile and motile macroinvertebrates (invertebrates large enough

to be visible to the unaided eye).

!

9

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!

IN

All plots were photographed during each sampling period using slide film in a handheld 35-mm m

camera with a flash attachment. Three photographs were taken of each plot: one of each of the

two 1 x 1-m plot halves, and one end-on view of the whole plot. The slides were labeled with •

date, site, and appropriate plot identification numbers and archived to provide a permanent, |

visual record of the plots over time.

Macroorganism abundance in the plots was measured in two ways, as percent cover and density. I

Percent cover, or the proportion of a plot occupied by a given organism, was determined for all

macroorganisms, including both sessile and motile macroinvertebrates. Percent cover is a n

measure of space, which is a critical limiting factor in intertidal communities, especially for

macrophytes and sessile macroinvertebrates such as mussels and barnacles. Density, or number

per unit of area, was determined only for motile macroinvertebrates, which exert influence on n

intertidal communities through grazing and predation pressure.

Cover in each quadrat was determined using a point quadrat methodology, which is described in n

detail in Foster et al. (1991) and depicted in the cover photographs. The point quadrat consisted I

of a clear plastic plate with a grid of 64 equally spaced holes mounted on adjustable legs above

the substratum. Twenty of the possible 64 points were chosen at random for each sampling •

period. Sampling was done by lowering a sharpened pin through the appropriate holes and

I

recording the macroorganisms and/or substrata contacted. Multiple contacts under a single point n

were sampled by moving aside successive layers of macroorganisms (multiple contacts of the I

same taxa were recorded as a single hi0.

Three levels of substratum were identified: primary, secondary, and tertiary. Primary I

substratum included bare rock, rock (rock covered by a macroorganism, but also contacted by the

pin, such as rock with an overstory of the rockweed Pelvetia), shell debris, and sand. All of the •

bare rock and most of the rock remained available for the settlement and growth of II

macroorganisms. Secondary substratum consisted of the biota that were attached directly to the

primary substratum (e.g., mussels). Tertiary substratum included the biota attached to the n

secondary substratum (e.g., barnacles or macrophytes attached to mussels). Typically, most of

the available substratum in undisturbed mussel beds was secondary or tertiary substratum.

m

Once the cover within the quadrat was determined by this method, all motile macroinvertebrates m

larger than 0.5 centimeters in length were counted in the quadrat. Most of these were algaegrazing molluscs such as limpets, snails, and chitons, but sea stars and sea urchins were also n

encountered. Qualitative notations were also made of other small macroinvertebrates such as

n

crabs, worms, and isopod crustaceans. Because of the difficulty of sampling macroinvertebrates n

within the mussel beds without disturbing the plots, the abundances of these organisms were I

undoubtedly underestimated for the MytiIus plots.

roll

In addition, motile macroinvertebrates measuring less than 0.5 cm in length were subsampled in N

the field by counting the number in a 10 x 10-era quadrat placed in the center of the larger

!

lO |
I quadrat(shown in the upper left cover photograph). Numbers of the smaller organisms were then adjusted to the full 25 x 25-cm (0.0625-m z) quadrat density by multiplying by 6.25.

I All macmorganisms observed were identified to the lowest taxon feasible. Representative

samples of species that could not be identified in the field (voucher specimens) were collected

and preserved for later identification. Macrophytes were identified according to Abbott and

I (1976) and et al. (1989), and macroinvertebrates to Smith and Hollenberg Scagel according

Carlton (1975) andLindberg (1986). Recent publications were used to obtain more current

taxonomic nomenclature (Abbott and Norris, 1985; Kozloff, 1987; Scagel et al., 1989; Silva,

I 1990; Richards, 1992; Hommersand et at., 1993). Some macroorganisms (e.g., small algal

blades, small limpets) could not be identified to species. The term "sp(p)." in the tables and

i finames gures dodenonottesexmac ist formorganisms many interoftidaonel macrophy or more unidentifi tes and macro ed speinver cies.tebraSinteces, sgenera tandardl common

morphological terms were used to describe the taxa in this report.

I Some macroorganisms were combined into larger groups for certain analyses. Total grazer

density was calculated and discussed as a group. "Grazers" comprised all the herbivorous

I macroinver chitons, andtebra an occasion tes observal edseainurchin the pl.otsGrazers , mostlyaregasknown tropodtomaffec olluscs t the(liabundan mpets andce sna andils),

distribution of the macrophytes that serve as their food, affect other macroinvertebrates, and, as a

I consequence, play a role in determining succession and community structure within the intertidal

habitat (Ricketts et al., 1985).

I Not all snails are grazers. Several predatory,or carnivorous snail taxa (including the genera

NuceIla, Acanthina, Ocenebra, Mitrella, and Epitonium) were also observed in the plots. These

snails may prey upon macroinvertebrates such as barnacles, mussels, limpets, anemones, and

I other snails.

Several taxonomic combinations that were used during the original study by KLI also were

I adopted for this report. Two rockweed genera, Pelvetia and Pelvetiopsis, were lumped into

Pelvetia-Pelvetiopsis sp(p), due to the difficulty of distinguishing juveniles of the former from

i adul Petrtsocelis of thane latt d toerth. osPetrocel e that aris esalp(tep)rnative , refersliboth fe stages to recoogniz f theegenu d spsecie Mastocarpus s of the cr. nstoThse rteedrmalga

GATGOR is an acronym for "green algae that grows on rocks," a thin, green slime thatmay

I inreclude liably aidentifi varietyedoftojuveni speciesle macrophyte in the field.s, blue-green algae, and diatoms, but which could not be

I Among the macroinvertebrates, taxa that could not be reliably identified to species level in the

field were the barnacles Chthamalusfissusldalli, which were reported as Chthamalus sp(p)., the

littorine snails Littorina scutulatalplena, and most small (<0.5 cm) Lott/a sp(p), limpets.

I

I

11

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mm

Two additional taxonomic changes were made during the currentstudy: I

1) The various species of membranous green algae in the genus Ulva were combined as II

Ulva sp(p)., because the individual species are only identifiable through laboratory II

analysis, and it has proven impracticable to voucher specimens from every plot sampled.

2) The fleshy red alga Iridaeaflaccida was combined with Iridaea cordata, then lumped m

1

into lridaea spIendens based on a recent taxonomic reclassification (Scagel et al., 1989).

I

A number of other taxonomic reclassifications of macroinvertebrate and macrophyte species I

have been made recently based on type specimens. Those changes are listed in Table 3 and will

be reflected in future reports for this study. However, the changes were not incorporated into this

report in order to facilitate comparison of the 1992 data with that collected during the initial

study (Kinnetic Laboratories, Inc., 1992).

Since within-plot variation was not of interest, the mean of the percent cover data from the three U

quadrats at any one sampling period and the sum of the motile maeroinvertebrates counted --

(including macroinvertebrates counted in the 10 x 10-em quadrats by scaling the counts to 0.25 x •

0.25 m) were used in analyses. Thus, densities of motile macroinvertebrates are per 0.1875 me

m

(0.0625 mex 3), and each plot represents n = 1. The numbers presented in the tables were mm

rounded to the nearest tenth, numbers in text to the nearest whole number. I

In addition to the procedures described above, all mussels were counted in each of the sampled m

quadrats in fall 1992 for comparison with similar data collected during the original study. I

Comparison of Methods with Ori_nal Study m

As described above, the field methods employed for this study were, for the most part, identical

to those used during the original KLI study. However, there were some differences, which are •

summarized here.

Only four of the original six sites were sampled during this study. Sites were sampled every n

other fall. In contrast, the sites were sampled each spring and fall during the original study. The II

cleared plots in the Endocladia/Mastocarpus assemblage were not sampled in this study.

Field sampling techniques differed in two ways between the studies. In this study, three m

photographs were taken of each plot sampled, to provide a permanent visual record. Eight n

photographs,

including close-ups of quadrat pairs, were taken of each plot during the KLI study, i

KLI measured all mussels in the cleared plots in the field during the original study, in an attempt m

to track changes in size-frequency distributions through time. In contrast, mussels were counted II

in all sampled quadrats in the field in fall 1992, for comparison with the original study, but the

mussels were not measured, n

12 I
I

I Table 3. Recent changes to macrophyte and macroinvertebrate

nomenclature for taxa observed in this study?

I Previous Current

Taxon Taxon

I

MACROPHYTES

I Plmeophyta

I Hesperophycus harveyanus = Hesperophycus californicus

i Rhodophyta

Gigartina canaliculata = Chondracanthus canaliculatus

• lridaea cornucopiae = Mazzaella cornucopiae

i I lridaea heterocarpa = Mazzaella heterocarpa Iridaea splendens = Mazzaella splendens

I Rhodoglossum affine . = Mazzaella affinis

MACROINVERTEBRATES

I Pelecypoda

I Mytilus edulis = Mytilus gaUoprovincialis/trossulus

"CoUisella" scabra = Macclintockia scabra

I

MacrophytechangesmefromAbbottandNorris(1985),Scageletal.(1989),Silva(1990), '

andHommersandetal.(1993). Macroinvertebratchang e esarefromKozloff(1987)and

I Richards(1992).

I

I

I

I
!

Kinnetic Laboratories, Inc., (1992) observed seasonal variation in abundance for a few taxa m

during their study. In order to avoid possible confusion due to seasonal variation, and for N

i

consistency, it was decided that data collected during this study would be compared only with

data collected during the fall sampling periods in the original study. The only exception to this •

was the inclusion in this report of data from the spring 1991 sampling period (see Appendix), the |

last sampling effort in the original study. The spring 1991 data provided a bridge between the

fall 1992 data and the data collected during the last fall sampIing period of the original study in •

I989 (a 3-year gap). Data collected during spring sampling periods were also used in

construction of the figures depicting plot recovery.

As in the original study (Kinnetic Laboratories, Inc., 1992), the recovery of the cleared Mytilus

plots was determined using the Bray-Curds index of similarity based on percent cover estimates

of sessile taxa (Bray and Curtis, 1957; GoodalI, 1978; Pielou, 1984). The range of similarities of 1

the control plots to each other (i.e., 1 vs. 2, 1 vs. 3, 2 vs. 3) at each sampling event was used to

set the limits of a control percent similarity envelope. The similarity of the cleared plots to the n

controls was determined by calculating the similarity of each cleared plot to each of the three II

control plots, then determining the mean of these values. The mean of the cleared plot similarity

lira

values was then plotted relative to the control envelope. The three cleared plots within the mm

Mytilus assemblage were considered to have recovered when their mean similarity to the control II

plots was equal to or greater than the least similar pair of control plots in the same sampling

period (the bottom of the range of similarity values among the control plots). •

Percent recovery was calculated by dividing the mean percent similarity for the cleared plots by

the percent similarity of the least similar pair of control plots (i.e., the comparisondefining the •

lower limit of the recovery envelope at a given time), then multiplying by 100. Recovery rate for |

each u_vered plot was calculated by dividing percent recovery by the number of months to

the last sampling date. •

|

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14 |
I HI. RESULTS

A. Kibesillah Hill

I 1. Mytilus Assemblage

i Wh of faillel rec 199ov2,erythatwathse cMyti ontilus nuinasgseinmtblage he bothwastheprobably spring- ayendarsfallaway -clearefromd plfuots, ll rieco t seemed very atclear, as

Kibesillah Hill. The Bray-Curtis index of similarity from the fall 1992 cleared plots was

i cobelmopw,aredthe toconthetrolindplots ex ofresimmaiilnaedritysimilar for theovfaerll time, 1992 canondtrol the plo cleared ts (Figuplots, re 2)whil . Ase vediryscussed similar to

each other, were still very different from the controls. The spring-cleared plots were 39 percent

I recovered, and the fall-cleared plots were 4I percent recovered (Table 4). Although complete recovery had not occurred by fall 1992, comparison of the fall 1992 results with previous years

indicated that recovery was continuing at a very slow rate.

I The control plots at Kibesillah Hill were relatively low in species richness and were dominated

by the mussel Mytilus. The total number of taxa in the Mytilus control plots at Kibesillah Hill in

fall 1992 was 14 (2 macrophytes and 12 macroinvertebrates, Table 5). Total macrophyte cover in

I was percent, cover was very high (130 percent).

fall 1992 23 Total macroinvertebrate

i As coverdescribe and density. d in the The methods, macroorganism abundance was measured in two ways, as percent

taxon with the most cover in the control plots in fall 1992 was the mussel

Mytilus californianus, with a cover of 99 percent (Table 5). The mussels in these plots were

i plots large,were averaoften ging 7observed to 8 can toin form length,hummocks densely aggre 5 to ga10ted, musanselsd thitall. cklyThelayenreextd. most Musseabundant ls in these

macroorganisms in terms of cover were the barnacles Chthamalus sp(p). (13 percent), which

I high were macroinvertebrate generally layered oncovtoper (130 of thepermus censt)els.meThi ntions leaye d earingrliewr.asThproe bab tuftedly reresdponsi algableEndoctadia for the

muricata (12 percent) followed closely, along with the fleshy red alga Mastocarpus papillatus

I (11 percent) and the sea anemone Anthopleura elegantissima (11 percent). Another barnacle, Balanus glandula, was also well represented in the plots with a cover of 5 percent. Shell debris

accounted for only 2 percent of the substratum observed in fall 1992 (neither bare rock nor rock

I was observed). Refer to the methods for definitions of rock, bare rock, and other terms used in this report.

I The density data showed that several motile macroinvertebrates in the

were comlnon plots

(Table 5). The most abundant macroinvertebrates (density expressed as no./0.1875 m2)were the

I

i 15

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I

Table 5. _croph_e, macrolnveMebrate, and substratum _un_ances in the

Mytilus assemble con_oI plo_ at K_m_ Hm dufi_ f_ 1_:

Taxmff Standm_ I hh_m Mean Deviation

_croph_es - Cover _ercent) I

Endocladia muricata 12.2 3.5 I

Mastocarpuspapillan_ 10.6 6.7 1

TotalMacrophytCov e er 22.8

M_rolnvmeb_ - C_er _ercent)

My_hts ca//forn/anus 98.9 1.0 •

O_thanuff_ sp(p). I3.3 7.6

Anthopleura elegantissima 10.6 8.6

Ba/anusg/andu/a 5.0 5.6 •

Tegulafunebralis 1.1 1.9 1

Littorina scutulma/plena 0.6 1.0

Loffm _g_a_ 0.6 1.0

To_flMacromver_bra_ Cover 130.1 l

Macrotnvertebrates- Density _o.10.1875 m_) I

I

Tegulafunebra//s 28.3 15.0

Littorina scutulma/plena 21.4 27.7 •

"Co///se//a"scabra 10.8 8.6 1 Lotfia tffgita//s 7.0 2.7

Lott/a//matu/a 2.4 4.2

LoUmpeLta 0.7 0.6 !

NuceUaemar_nma 0.7 0.6

Echinodermu,nid_. 0.3 0.6

Ill

T_ Nm_ of Ma¢_ Taxa 2 I

Total Number of Ma_dnv_ebrate Tan 12

Total Number of All Tan 14 •

Substratum - Cover (Percent) n

Shelldebris i.7 1.7

[]

Damarc mea_ of_e _ott (n=3), Taxaand mbsmm within_c,h ca_gory are ranked 1

accordingm the means, then g_d _phabefica_y ff the means are equal. To_ petcem cover can

exceed 100 percentbecause multiplelayers wen: sampled. •

I

lg |

, !
I snail TegulafunebraIis (28) and the littorine snails Littorina scutulata/plena (21). Two limpets, "CoIIisella" scabra and Lottia digitalis, were also common, with densities of 11 and 7,

respectively. Total gazer density included 28 Tegula snails, 21 littorine snails, 21 limpets, and 1

I echinoderm.

In general, the number of all taxa steadily decreased from 18 at the beginning of the study, when

I began monitoring plots, to (Table A-I). The total number of KLI these 14 in fall 1992

macrophyte taxa decreased over time, from 5 in 1985 to 2 in 1992. The total number of

i ma 1992. croinAt vertebra Kibesillah te taxHill, a went a grand up totot15alinoffall 28 1986 taxa (including and 1987, but 19 macroinvertebrates decreased to 12 in fand all 1989 9 and

macrophytes) was observed in the control plots since 1985.

I The mussel Mytilus californianus consistently was the most abundant macroinvertebrate in the

control plots, with cover ranging from 90 to 100 percent since the mid- 1980's (Table A- 1). The

I abse in thnesece plots. of unocThe cupied onlyprimary substratumsubsthat tratumconsistently also pointeshowed d to theuphiginh the coveplots, r andeven densinitysmall of mussels

amounts, was shell debris. Bare rock, rock, and sand had cover values of less than 1 percent or

were absent.

Cover by the barnacles Chthama/us sp(p)., which ranged from 1 to 4 percent during previous fall

I surveys, increased to 13 percent in 1992 (Table A-l). The stability of the mussel bed at this site

may have allowed for increased settling and growth by ChthamaIus sp(p). The sea anemone

Anthopleura elegantissima also was more abundant in 1992 than in previous fall sampling

I periods. Abundance of this taxonat KibesiUab Hill varied throughout the study; some of this

variability may have been due to the patchiness of this taxon. In general, organisms with a

patchy distribution will show up in the data as variable over time, since different quadrats within

I the plot were sampled each sampling period. This may explain the higher cover values of this

sea anemone in fall 1987 and 1992. The barnacle Semibalanus cariosus, while present in low

i abundances during previous years, was not observed in 1992.

Total maeroinvertebrate cover varied only slightly over the study period (109 to 116 percent)

i withas pthriemeaxcrilyeptidouen tofthfall e sh199arp2,inwhe creansecover in coveincrr eabysethd etoba1rna30clperc es enChtt.hamal Thisusincre sp(asp).e in fall 1992

i papi TwoUtaxa, atus,thweereredptartic uftedularly alga abunda Endocladia nt in muri 1992ca, wtaheann dcover the flvalues eshy re(12d alganadMas 11 percent, tocarpus

respectively) were two to three times higher for both taxa than in previous fall sampling periods

I (ranging from 0 to 5 percent, Table A- 1). Cover values were also higher in spring 1991, [Endocladia (21), Mastocarpus (7), Table A-2], indicating that this upward trend had begun by

spring 1991 and continued into 1992. The foliose red alga Porphyra perforata, which was not

I observed in fall 1989 or fall 1992, ranged as high as 38 percent during previous fail sampling periods. Total macrophyte cover varied over the study period, ranging from 4 percent in fall

1986 to 43 percent in 1988, with fall 1992 well within this range (23 percent). The decrease !

19

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I

I

from fall 1988 and 1989 to fall 1992 was largely due to the decline in the foliose red algae I

Porphyra perforata and Porphyra Ianceolata.

The macroinvertebrate density data indicated that the most abundant macroinvertebrates in fall !

1992 were common in the plots in previous fall sampling periods. While densities varied, the

littorine snails Littor/na scutuIata/pIena, the snail Tegulafunebralis, and limpets "Collisella" •

scabra and Lottia digitalis were abundant in the plots every fall sampling period since 1985 I

(Table A-I). However, based on data from fall sampling periods between 1985 and 1992, it

appears that Lottia paradigitalis declined in the plots. Lottia paradigitalis was not observed in []

fall 1992; it reached a high of 12 per 0.1875 m2in fall 1988, but dropped to 1 in fall 1989.

A comparison of the Mytilus control plots, using the Bray-Curtis index of similarity, indicated I

that in fall 1992 the plots were very similar to one another and had been very similar to each

I

other throughout the 1985-1992 study (Figure 2).

Spring.Cleared Plots I

Based on the number of taxa, the spring-cleared plots were very diverse. In fall 1992, there were I

16 macrophyte taxa and 18 macroinvertebrate taxa in these plots at Kibesillah Hill (Table 6).

I

Total macrophyte cover was 100 percent in the spring-cleared plots; total macroinvertebrate II

cover was 34 percent. I

While not the most abundant taxon, the mussel MytiIus californianus was the most abundant I

macroinvertebrate in the spring-cleared plots and reached a new cover maximum in fall 1992 (21 l

percen0 (Table 6). Observations indicated that one of the spring-cleared plots still had very little

Mytilus, while mussel cover was substantial in the other plots. In the plots where mussel •

recovery was proceeding well, it appeared that both recruitment and encroachment were factors I

in the increase in mussel cover. Clusters of small mussels were found in the interior of the plots;

large layered mussels were found encroaching from the perimeters. Despite the continued I

progress toward recovery, however, total abundance was still considerably less than the total

mussel cover present in the control plots at this site.

Rock accounted for 29 percent of the substratum in the spring-cleared plots in fall 1992. I

Macrophyte taxa contributed the most cover (Table 6). Two of these taxa, the tufted green alga

CIadophora columbiana and the branched red alga Odonthaliafloccosa, made up almost half of I

the total cover, with an abundance of 24 percent each. The standard deviation value for the

m

branched red alga Odonthaliafloccosa was unusually high (40). Observation and review of the I

plot data showed that Odonthalia had high cover in one of the plots and was sparse in the others. I

Other macrophytes contributed another 45 percent to the total cover (Table 6). These included

the fleshy red alga Mastocarpus papillatus (10 percent), the tufted red alga Endocladia muricata I

(8 percent), the articulated coralline alga Corallina vancouveriensis (8 percent), the rockweed

Fucus gardneri (5 percent), the branched red alga Neorhodomela larix (5 percent), the fleshy red I

20 I
I Table 6. Macrophyte, macroinvertebrate, and substratum abundances in the Mytilus assemblage cleared plots at Kibesillah Hill during fall 1992. _

I Taxon/Substratmn Spring- Mean CleS.D. ared2 MFall-Clear ean eS.D. d

Maerophytes - Cover 0Pereeat)

Cladophora co/umb/ana 24.4 8.2 15.2 14.2

I Odonthaliafloccosa 24.4 39.5 1.7 2.9 Mastocarpus papillatus 10.0 10.4 19.4 15.1

Endocladia muricata 8.3 11.7 1.1 1.0

Fucus Cora//inagardvancou ner/ ver/ens/s 7.8 5.0 9.2 7 3 9. 4.4 56.63

Neo_/a/ar/x 5.0 5.0 0.6 1.0

Ir/daea heterocarpa 3.9 2.6 1.7 1.7

Iridaea splendens 3.3 5.8 2.8 2.6

Polysiphonia hendryi 2.2 3.9 -

Petrocelis sp(p). 1.7 2.9 2.2 3.9

Brown Crustosecrucorallines, sts unidem. 1. 1.11 1. 1.09 11.1.1 11.9.0

PeIvetia-Pelvetiopsis sp(p) 0.6 1.0 0.6 1.0

Bossiella plumosa 0.6 1.0 0.6 1.0

Red crusts 0.6 1.0 1.7 1.7

Ana//pus japon/cus 0.6 1.0

Halosacdon americanum 0.6 1.0

l Prionitis ianceolata 0.6 1.0 Ral_/asp(p). 0.6 1.0

Total Macrophyte Cover 100.0 66.0

Macroinvertebrates - Cover (Percent)

My_/us ca/ifom_mus 21.1 I3.9 19.4 11.7

Chthanm/gs sp(p). 5.6 4.8 5.6 3.9

Anthopleura elegamissima 2.2 2.6 2.8 2.6

l Ba/anus g/andu/a 1.7 1.7 1.7 2.9

Tegula funebralis 1.1 1.0 1.7 1.7

Tetraclita rubenscens 0.6 1.0 5.0 8.7

I Pagurus Pollicipespol sp(p) ymerus 0..66 1..0 0.6 1.0

NuttaIina californica 1.1 1.0

_ dig_s 0.6 1.0 Lot//a pe/m 0.6 1.0

Semibalanus cariosas 0.6 1.0

l Total Mafroinvertebrate Cover 33.5 39.7

I

1 21

I
I

II

Tale 6. _croph_, macroinv_ebrate, and substratum abundances in he Mytilusassemble cleared •

plots at K[besillah Hill during fall 1992 1 (continued). I

Taxo_Su_mmm SM_e-anCI_ S.D: FalI- MeanCi_ S.D. I

M_rolnvm_rates - Density _o./0.1_5 m_ •

"CoUisella" scabra 22.3 32.7 32.6 52.1 1

Lott/a sp(p). 20.8 18.0 8.3 14.4 1

Tegula funebralis 8.0 6. i 9.7 7.0

I

NuceUa emarginata 4.2 7.2

Littorina sctaulata/plena 4.2 7.2 •

Lottia paradi gitalis 3.1 4.5

Lindaria succinta 2.1 2.6

Lott/a pe/ta 1.7 2.9 3.4 5.9 •

_a _g_ 1.0 1.7 5.7 9.8 1

Lott/a//matu/a 0.3 0.6

Mopalia muscosa 0.3 O.6

20 20 I

Total Nmaber of Macrophyte Taxa 16 19

aa

Total Number of Ma_v_brate Tan 18 13 !

Total Number of All Taxa M 32 •

__ - Cover (Percent)

Rock 29.4 24.2 12.2 10.0 1

Bare Rock 7.2 7.5 13.3 6.0

Sand 0.6 1.0

!

t D_m_meamof_-_(n=3). Tmm_w_m_h_tre__n_w_meansin_-

_m_ plots,_ listedg_y if themeansare_. Total_rcm _er cane_ 1_ _ _ m_e layerswere

sampled. A dub (-)indkatestheutxon/_bmammwu not reoordedia theplotsmdie.ated. I

2 S.D..= Smndl_ Deviation

I

I

22 I
I algae Iridaea heterocarpa (4 percent) and Iridaea splendens (3 percent), and the filamentous red alga Polysiphonia hendryi (2 percent). Among the macroinvertebrates, the barnacles Chthamalus

sp(p), and the sea anemone Anthopleura elegantissima had cover values of 6 and 2 percent,

I respectively. Bare rock accounted for 7 percent of the substratum in fall 1992.

Density data for the spring-cleared plots showed that the limpets "CoUiseUa" scabra (22/0.1875

I m2)and Lott/a abundant macroinvertebrates 6). The snail sp(p). (21) were (Table Tegula

funebralis (8), the predatory snail Nucella errmrginata (4), littofine snails Littorina

scutulata/ptena (4), and the limpet Lottia paradigitalis (3) were also observed in the plots. Total

I grazer density in the spring-cleared plots included 49 limpets, 8 Tegula snails, 4 littorine snails, 2

other snails, and 1 chiton.

I The number of taxa increased from a total of 20 in 1985 to 34 in 1992 (Table A-3). This increase

was generally due to an increase in macrophyte taxa. The grand total number of taxa observed at

I Kmibe acroin sillahvertHill ebratein theandspring-cleared 26 macrophyteplotaxts a.since 1985 numbered 58, including 32

I Abundance of the mussel Mytilus californianus increased over time at this site, with a sharp increase from 4 percent in fall 1989 to 18 percent in spring 1991 and 21 percent in fall 1992

(Table A-3, Table A-4). It was the most abundant macroinvertebrate since fall 1989 (Table A-3).

I It appears that some community changes occurred in one of these plots. This conclusion is based

on the comparison of cover values for previously studied fall sampling periods with those for fall

I 1992 (Table A-3). In fall 1987, 1988, and 1989, macrophyte cover was shared between the fleshy red alga Mastocarpus papillatus, the branched red alga Neorhodomela oregona, the tufted

red alga Endocladia rauricata, and the tufted green alga Cladophora columbiana. The branched

I red Neorhodomela in had abundances in 1988 and in alga oregona, particular, high (30percent)

1989 (24 percent). However, in fall 1992, both the branched red alga Odonthaliafloccosa and

the tufted green alga Cladophora columbiana increased considerably, while the branched

I alga Neorhodomela oregona was absent and the fleshy red alga Mastocarpus papilIatus was at its

lowest cover value in the sampled portion of the plot. The transition from high cover of

N19eorhodo 89, whenmelabothortaxegona a wetore higobhserved coverinoftheOdoplnthaIia ots in lflocc ow abosaundaapncepasrentl (Kiynnwetiasc bLaborat eginninogries, in spring Inc.,

1992).

I Some motilemacroinvertebrates showed decreases in densityin1992 compared to previous years

(Table A-3). In particular, the limpets "CoUiseUa" scabra, Lottia pelta, Lottia digitalis, and

I Lottia sis(p)., as well as the littorine snails L/ttotina scutulata/plena, were at their lowest levels in the plots since fall 1986. A decreasing trend over time would be expected as the assemblage

matures, both because there are less algae to forage upon, and because macroinvertebrates are

I harder to see in the dense mussel bed. In the case of the littorine snails, however, whose densities decreased from a peak of 577 in fall 1986 to 4 in fall 1992, some additional factor may

have beeninvolved.

!

23

!

|
!

i

The amount of rock varied over the study, ranging from 6 percent in 1985 to a high of 43 percent i

in 1987 (Table A-3). The amount of bare rock was low in 1992 (7 percent) compared with that

observed during other fall sampling periods, which ranged between 16 percent in 1988 and 74 •

percent in 1985. I

Total macrophyte cover at KibesiUah Hill increased over the study period. Since fall 1987, the •

cover ranged between 84 and 101 percent, with fall 1992 at exactly 100 percent (Table A-3). l

Total maeroinvertebrate cover was variable, ranging from a high of 34 percent in fall 1986 to a

low of 13 percent in fall 1989. Fall 1992 cover data indicated that total macroinvertebrate cover IIi

had increased due to the large increase in Mytilus cover. The higher percent cover in the early

years of the study was due primarily to barnacle cover.

The Bray-Curtis index of similarity was used to examine recovery of the spring-cleared plots, i

This index does not look at mussel recovery specifically, but rather compares the similarity of

species composition and abundance for the entire assemblage sampled in the cleared plots to the i

entire assemblage sampled in the control plots. As seen in Figure 2, which graphs these i

similarity values, recovery was continuing in the spring-cleared plots, but full recovery was i

probably still years away. By fall 1992, the plots had recovered 39 percent (Table 4). Mussel 1

density dropped sharply from 121 in spring 1991 (Table A-5) to 39 in fail 1992 (Table 7). This

drop, in combination with the increased mussel cover over this same period, could reflect a loss n

of small mussels. More likely, however, this drop reflects the variability among quadrats within I[

a plot, since the same three quadrats were not sampled each sampling period. It is possible,

therefore, that the quadrats sampled in spring 1991 had many small mussels, whereas the •

quadrats sampled in fall 1992 had fewer, large mussels. The rate of recovery remained very !

slow, dropping slightly from a rate of 0.47 percent per month in spring 1991 to a rate of 0.43

percent per month in fail 1992 (Table A-5, Table 7). i

Ill

Fall-Cleared Plots

In fall 1992, the number of macrophyte taxa observed in the fall-cleared plots at Kibesillah Hill i

was at the highest level since 1986. Nineteen macrophyte and 13 maeroinvertebrate taxa were

observed in these plots in 1992 (Table 6). Total maerophyte cover was lower in the fall-cleared i

plots (66 percent) compared to the spring-cleared plots (100 percent). Total II

maeroinvertebrate cover in the fall-cleared plots (34 percent) was similar to that in the springcleared plots (40 percent), i

At 19 percent cover, the mussel Mytilus californianus was the most abundant macroinvertebrate II

taxon obselNed at Kibesillah Hill in fall 1992 (Table 6). Encroachment and recruitment are 1

occurring in the fall-cleared plots. Placement of one of the plots in a slight depression where

i

water is always present may favor settling by other organisms, thus impeding mussel recovery in •

this plot. In another plot, a small elevation at one comer appeared to be slowing encroachment to 1

that portion of the plot.

!

24 |
I
!

As previously mentioned, macrophytes provided the most cover in the fall-cleared plots in 1992.

The fleshy red alga Mastocarpus papilIatus was the most abundant (19 percent), followed by the

tufted green alga Cladophora columbiana (15 percent), the articulated coralline alga Corallina •

vancouveriensis (9 percent), the rockweed Fucus gardneri (4 percent) and the fleshy red alga I

Iridaea splendens (3 percent), and the crustose red algae Petrocelis sp(p). (2 percent). Several

macroinvertebrates also provided cover in the plots. The barnacles Chthamalus sp(p). (6 percent) •

and Tetraclita rubescens (5 percent) accounted for a small amount of cover. The sea anemone

Anthopleura etegantissima was also observed (3 percent). Bare rock accounted for 13 percent,

and rock 12 percent of the substratum in the fall-cleared plots. 1

Relatively few motile macroinvertebrates, were observed in the fall-cleared plots. The limpet

"ColliseUa" scabra was common in the plots, with a density of 33 per 0.1875 m2. The next most

abundant macroinvertebrate was the snail Tegulafunebralis (10). Other limpets observed were

g

Lott/a sp(p). (8), Lottia digitalis (6), and Lottia pelta (3). No littorine snails were observed in the

plots in fall 1992. Total grazer density consisted of 50 limpets, 10 Tegula snails, and 2 chitons. I

Peaking in 1987 with 18 taxa, the number of macroinvertebrate taxa observed in the fall-cleared I

plots decreased to 13 in fall 1992 (Table A-6). In contrast, the number of macrophyte taxa H

observed increased over this same period, from 10 in 1986 to almost double the original value

(19) in fall 1992. In total, 52 different taxa, including 26 macroinvertebrates and 26 •

•macrophytes, were identified in the fall-cleared plots. l

Although not the most abundant taxon, total cover by the mussel Mytilus californianus was at its •

highest level in the fall-cleared plots in fall 1992 (Table A-6), continuing a pattern of increasing 1

cover that began in fall 1989. Mussel cover rose from 10 percent in fall 1989, to 17 percent in

spring 1991 (Table A-2), and to a new high of 19 percent in fall 1992 (Table A-6). gi

Cover of the fleshy red alga Mastocarpus papillatus was essentially the same in fall 1992 as in

fall 1989 (19 percent vs. 18 percent), making it the most abundant maerophyte for the fast time

in fall 1992 (Table A-6). The fleshy red alga lridaea splendens generally decreased from the

beginning of the study, from a high cover value of 21 percent in fall 1986 to a low of 3 percent in

fall 1992. Maerophyte cover of the remaining taxa varied in these plots over the sampling

period, although major trends could not be identified. Bare rock and rock cover both decreased II

roughly by half from fall 1989 to 1992 (from 21 to 13 percent and 24 to 12 percent, respectively).

I

The density of the limpet "CoUiselIa" scabra in fall 1992 (33/0.185 m2) was consistent with

previous years, except for fall 1987 when the density was very low (3, Table A-6). Density of the I

snail Tegulafunebralis in fall 1992 (10) was also similar to that observed in previous years,

when cover ranged from 5 to 11. The IimpetLottiapelta (3) was also observed in fall 1992 at a

density similar to previous fall sampling periods (0 to 5). However, other limpets and littorine •

snails were present in low abundances compared with previous fall sampling periods, or were not I

observed. The small limpets Lott/a (sp)p., in particular, showed a large decrease from fall 1986

I

26 |
I (123) to fall 1992 (8). These lower abundances were consistent with the low macroinvertebrate abundance also observed at this site in the spring-cleared plots in fall 1992.

I maerophyte cover plots not a pattern over study Total in the fall-clea_d did follow clear the

period (Table A-6). The lowest cover values were observed in fall t986 (51 percent) and fall

1992 (66 percent) with a peak in 1987 (93 percent). Total macroinvertebrate cover was

I somewhat less variable in previous fall sampling periods, ranging between 16 and 27 percent,

though a notable increase occurred in fall 1992 to 40 percent. This increase in fall 1992 was

i largely due to the increase in Mytilus.

The fall-cleared plots at Kibesillah Hill were 41 percent recovered (Table 4). Based on the BrayI Ctheir urtisreindex coveryofatsimilarity this site,(Fig theufall re 2). -cleared The length plots woferetimeslightly neededbehin fordfull therecovery spring-cleared is unknowplonts, inbut

is probably years away. Mussel density in the fall-cleared plots remained constant at 63 between

I esssentially pring 1991thane dsafall me between 1992 (Tabl spri e nA-5; g 1991 Tablande 7).fallThe1992rec(0.48 overy torat0.49 e remain percent ed vper erymonth, low and was

respectively).

|

I The in the control varied time between 1986 and

assemblage Endocladia/Mastocarpus plots over

1992. Total macrophyte cover and total rnacroinvertebrate cover were lower in fall 1992 than

i they had been in fall 1989.

Caa, tmLP_la

I Equalnumbers(I2 each)ofmacrophytcandmacroinvertebrtaatxeawereobservedinthe

EndodadialMastocarpausssemblag(Te able8).Totalmacrophytcove e rin1992washigh(89

I percent). Total maeroinvertebrate cover was low (14 percent).

Bare rock accounted for the greatest amount of area (27 percent) in the control plots in fall 1992

I (Table 8). The tufted red alga Endocladia muricata covered a fairly large portion of the substratum (18 percent). The brown rockweed Fucus gardneri was the most abundant taxon,

with an average cover of 22 percent. Rock accounted for 19 percent of the plot area.

I The tufted green alga Cladophora columbiana and fleshy red alga Mastocarpus papillatus also

provided a fairly large amount of cover in the plots, with abundances of 13 and 11 percent,

I respectively (Table 8). Other red algae, the cmstose Petrocelis sp(p), and the fleshy Iridaea splendens, were present with cover values of 7 percent and 4 percent, respectively. Coralline

i algae were also well represented: the articulated alga CoraUina officinalis covered 5 percent, and

| ,-7

!
m

Table 8. Macropbyte, macroinvertebrate, and sub_ratum abundancesin the •

Endocladia/Mastocarpus assemblage control plots at Kibesillah Hill i

during fall 19927

Standard n

Taxon/substratum Mean Deviation

I

Maerophytes - Cover (Perceat)

Fucus gardneri 22.2 22.5 n

Endoc/adia tour/cam 17.8 10.6

i

Cladophora columbiana 13.3 11.7

Mastocarpus papillatus 11.1 3.5 l

Petrocelis sp(p). 7.2 9.8

_r_na _ 5.0 7.3

Crustosecoraltines, tmident. 3.9 4.2 •

lridaea splendens 3.9 5.4 |

Halosaccion americanum 1.7 1.7

Redcrus_ 1.7 2.9 I

Neo_la larix 0.6 1.0 •

Pelvetia-Pelvetiopsis sp(p). 0.6 1.0

TotalM_h_ Cover 89.0 l

Im

Mm__m - _ver _m)

c_,m_ sp(p). 5.0 6.0

Mytilus californianus 1.1 1.9

o6 1o l

Linorina scutulata/plena 0.6 1.0

I

TotalM__roinve_a_ C_er 14.0 l

Ma_Jv_ebrat_ - _ _o.10.1_5

L/ttor/na scum/ata/p/ena 30.6 32.5 n

Lott/a sp(p). 6.3 12.6

i

Tegulafunebralis 10.3 6.1

Lottia digitalis 0.3 10.8 n

"CaTllisellascabra " I1.0 1.2 Q

Nucella emarginata 0.7 0.6

as_ 0.3 0.6 •

Lott/a//matu/a 0.3 0.6 I

Total Number ofMaerophyte Taxa 12

Total Number of Macroinvertebrate Taxa 12 •

Total Number of All Tan 24 i

2s i
I

I Table 8. Maerophyte, macroinvertebrate, and substratum abundances in the

Endocladia/Mastocarpus assemblage control plots at Kibesillah Hill

I during fall 1992 1(continued).

Standard

i Taxoa/Substratum Mean Deviation

Substrata - Cover (Percent)

I Rock 18.9 8.2

Bare rock 27.2 19.2

I Shelldebris I. I 1.0

' Dam are meam of three ptots (nffi3). Taxa and _tram within each calegory are ranked

I ac_ordil_ to the mea_, then iisled _befically ff Ihe mea_ are equal. Total percent c_er can exceed 100 permmt becuse mmltiple layers were sampled.

I

I

i

I

I

I

I

I

I

I

I 29

I
m

crustose corallines accounted for 4 percent. Macroinvertebrates provided a small amount of m

cover. The sea anemone Anthopleura elegantissima and the barnacles Chthamalus sp(p).

covered 7 and 5 percent of the substratum, respectively. The mussel Mytitus californianus also •

was observed at a very low abundance (1 percent). l

Motile macroinvertebrates were common in the plots (Table 8). These included the littorine •

snails Littorina scutulata/plena (31/0.1875 m2), the limpet "CoIlisella" scabra (11), and small m

limpets Lott/a sp(p). (6). The snail Tegula funebralis had an observed density of 10. Total

grazer density included 31 littorine snails, 18 limpets, and 10 Tegula snails, m

The total number of taxa and respective numbers of macrophyte and macroinvertebrate taxa

varied over time; 1992 values were within the range of values observed in these plots in previous m

fall sampling periods but both were lower than in fall 1989 (Table A-7). Overall, 40 taxa,

including 23 macrophytes and 17 macroinvertebrates, were identified in the control plots.

In comparison with most previous fall sampling periods, total macrophyte cover was down in m

1992 (Table A-7). Abundance of the fleshy red alga Mastocarpus papillatus, the tufted green m

alga Cladophora columbiana, and the rockweed Fucus gardneri were lower almost by half m

compared with fall 1989, and were also low in relation to fall 1987 and 1988. In the case of the

m

latter two maerophytes, abundance in spring 1991 was also unusually low (Table A-8). The m

roekweeds Pelvetia-Pelvetiopsis sp(p)., which had been relatively abundant in fall 1989 (22 m

percent) and spring 1991 (35 percent), were very low (less than 1 percent) in fall 1992 (Table A7). The tufted red alga Endocladia muricata had the same abundance in 1992 as in fall 1989; •

both years were low compared to all previous fall sampling periods in the control plots. Three m

grazing macroinvertebrates, the limpet "Collisella" scabra, the snail Tegula funebralis, and the

littorine snails L/ttor/na scutulata/plena, had unusually high densities in spring 1991, which may •

account for some of the lower macrophyte abundances in 1992. l

The amount of rock observed in 1992 (19 percent) was about half that observed in previous years m

(between32 and48 percent,TableA-7).Theamountofbarerockobservedin1992(27percent)

was much higher than that observed in previous fall sampling periods (between 4 and 24

percent). This increase in bare rock may have been related to the corresponding decrease in m

Fucus at this site.

A comparison of the EndocladialMastocarpus control plots from 1985-1992, using the Bray- m

Curtis index of similarity, indicated that there was considerable variation in the range of m

similarity of the control plots through time. However, similarity of the control plots in fall 1992 IN

was within the range of similarity observed for the control plots during previous years (Figure 3). m

m

30 m
I
I

B. Sea Ranch I

1. Mytilus Assemblage •

Based on differences between the Bray-Curtis index of similarity of control vs. cleared plots I

(Figure 4), neither the spring- nor fall-cleared plots in the MytiIus assemblage at Sea Ranch had

fully recovered in fall 1992, 7 to 7 1⁄2 years after being cleared. In fall 1992, the spring-cleared •

plots were 50 percent recovered and the fall-cleared plots were 34 percent recovered (Table 4). !i

Although complete recovery had not occurred by fall 1992, comparison of fall 1992 results with

previous years indicated that recovery was continuing at a very slow rate. I

B

In fall 1992, both macroinvertebrate species richness (number of species) and cover (percent) I

were much higher than that of macrophytes in the Mytilus assemblage control plots (Table 9). Of

the 14 taxa observed, 11 were macroinvertebrates and only 3 were macrophytes. Similarly, II

macroinvertebrate cover was very high (121 percent), while total macrophyte cover was low (8

percent).

Based on cover (percent), the mussel Mytilus californianus was the most abundant taxon in fall U

1992 (93 percent, Table 9). The mussels in these plots were mostly medium in size (about 5 cm), Ill

and there was some patchy multilayering of mussels. After mussels, the barnacles Chthamalus li

sp(p), and Balanus glandula (both 9 percent) were next in abundance, followed by the barnacle

m

Pollicipes polymerus (6 percent). I

Of the three macrophyte taxa observed in fall 1992, the only one that was somewhat common

was the tuRed red alga Endocladia muricata (6 percent, Table 9). Cover of the other two •

macrophytes, the filamentous red alga Polysiphonia hendryi and the crustose red algae Petrocelis 1

sp(p)., was less than 2 percent each. Shell debris (2 percent), bare rock, and rock (both 1 percent)

accounted for a very small area of the control plots. 1

Illl

The most abundant motile maeroinvertebrates based on density (no./0.1875 me) during fall 1992

(Table 9) were small limpets, Lott/a sp(p). (104). The limpet "Collisella" scabra was next in II

abundance (55), followed by the limpets Lott/a digitalis (33), Lott/a peIta (13), and Lott/a

paradigitalis (4). The only other motile macroinvertebrates observed in fall 1992 were the

predatory snail NuceIla emarginata (3) and the littorine snails L/ttor/na scutulata/plena (3). I

Total grazer density included 209 limpets and 3 littorine snails. 1

Comparison of species richness in fall 1992 with fall sampling periods from 1985 through 1989 I

(Kinnetic Laboratories, Inc., 1992) indicated that the number of macroinvertebrate taxa

I

observed in fall 1992 was only slightly lower than previous fall sampling periods (range 12 - 18, II

32 i
,l
1

Table 9. Macroph_e, macrolnve_ebrate, and su_mtum nhen_mces m the m Mytilus assemble control plo_ at Sea Ran_ dm_ f_ 1_. z

Tax_Sub_mtum Mean Standard _mfion m

_croph_es - Cover percent) m

E__ mun_a 5.6 1.9

Polysiphonia hendryi 1.7 1.7 m

Petrocelis sp(p). 0.6 1.0 I

T_ Mac_h_ Cover 7.9 1

m

M_mmvm_rates - Cover _erceat)

Mytilua califo.ffanus 93.3 2.9 l

Ba/anua gtanduta 8.9 5.1

__ _). 8.9 6.7

PoUicipes polymerus 6.1 3.5 m

Littorina scundata/plena 1.1 1.9

Lotr/ad/g/ta//s i.I 1.9

Lott_ pe/ta 1.1 1.0 •

NuceUa emarginma 0.6 1.0 1

T_ Macminve_bm_ Cover 121.1

M_mmv__ - Density _o.10,1_$ m_ •

Lan/asp(p). 104.2 64.2 I

"O_e_" $_ 54.8 62.2 1

_mm _#m_ 33.0 25.1

_ 13.1 10.0 •

/.,otaaparad/g/ta//s 4.I 4.7 I

NuceUa emargin_a 3.3 2.9

Liuorina scutulala/plena 2.8 4.8 •

Total Nmber of Macrophyte Taxa 3

Total Number of M_m_v_rate Tin 11 1I

Total Nm_ of All Tan 14

I

Shell debris 1.7 1.7 I

Bare Rock I. 1 1.9 l

Rock 0.6 1.0 m

Dataam meansof three#ors(n=3). Taxaandmbmamwithiaeachcategoryareranked I

according m tim mmms, then listed alphabetically if the means are eqwl. Total lmrcamt cover can

e_ i®_.._._J.__. w_.._ •

34

!
I Table A-9), but was the same as in spring 1991 (11, Table A-10). However, the number of

macrophyte taxa observed in fall 1992 (3) was more than 50 percent lower than in previous fall

sampling periods (7 - 9). The number of macrophytes (7) observed in spring 1991 was also

I higher than fail 1992. For all fall sampling periods combined, a grand total of 20

macroinvertebrate and I7 macrophyte taxa were observed in the MytiIus assemblage control plots

at Sea Ranch (Table A-9). !

From 1985-1992, total maerophyte cover changed substantially (Table A-9). During this period,

i todecline tal maero wasphyte due tocoaverdecline declinedin onefromtaxo43n,perc theentufted t in 1r98ed5alga to oEndocladia nly 8 percenmuricata t in 1992. , which Much of this

decreased from a high of 29 percent in 1987 to only 6 percent in 1992. Conversely, total

I ma (121croinv percent). ertebrate cover was relatively similar from year to year and was at its highest in 1992

I Aprevi s inousfallfall 1992, samthpelinmusse g period l MytiIus s (rangecalif 83ornianus - 94 percenwas, t, Tab by far le ,Athe -9).mos Hotwabeveundr, auntnliktaexonfallin1all 992,

the tufted red alga Endocladia muricata was the next most abundant taxon in previous years (16 -

I 29 percent). Although the abundance of Endocladia declined somewhat during the study period, Endocladia abundance was far lower in fall 1992 (6 percent) than either fall 1989 (16 percent,

Table A-9) or spring 1991 (18 percent, Table A-10). The abundance of two fleshy red algae,

I Mastocarpus papillatus (range 3 - 7 percent) and Iridaea splendens (1 - 4 percent), also declined. These two macrophytes were usually next in abundance after Endocladia muricata, but

Mastocarpus papillatus was not observed in fall 1989 or 1992, and lridaea spIendens was not

I observed in fall 1992.

As in fall 1992, limpets were also the most abundant motile macroinvertebrates in previous fall

I sampling periods (range 109 - 197/0.1875 m2). The three taxa with the greatest densities from

fall 1985 through fall 1989 were always limpets. Although the top three limpet taxa varied from

i yThe ear preda to year, they included "ColliseUa" scabra, Lottia digitalis, Lottia sp(p)., and Lottia pelta.

tory snail NuceUa emarginata was next in abundance (2 - 8), followed by the littorine

snails L/ttor/na scutulata/plena (0 - 7), the limpet Lott/a paradigitalis (0 - 6), and the snail

I Tegulafun sampling ebperiods ralis prio (0 -r3to). 1Th992, e dens andities all taofxathwee reremainin not observed g sevenintaeve xa we ry reyearlow. (<3) in fall

I As comparison of the Mytilus control plots from 1985-1992, using the Bray-Curtis index of imilarity, indicated that in fall 1992 the Mytilus assemblage control plots were very similar to

each other and about as similar to one another as they had been in most previous surveys (Figure

I 4).

!

35

!

!
Spring.Cleared Plots l

Compared to the control plots, species richness was higher in the MytiIus assemblage spring- .=

cleared plots at Sea Ranch in fall 1992. A total of 32 taxa, including 17 macroinvertebrates and 1

15 macrophytes, was observed in the spring-cleared plots (Table 10) vs. 14 taxa in the controls.

The number of macrophyte taxa was especially high in the spring-cleared plots (15 vs. 3), but the •

number of macroinvertebrates was also higher (17 vs. 11). Although the number of macrophyte I

taxa was similar to that of macroinvertebrates in the spring-cleared plots, total macrophyte cover

(32 percent) was only about half that of macroinvertebrates (63 percent). I

m

The most abundant macroinvertebrate based on cover was the mussel MytiIus caIifornianus (28

percent). The barnacles Balanus glandula (17 percent) and Chthamalus sp(p). (14 percent) were •

next in abundance, followed by the limpet Lott/a digitalis (2 percent). Total macroinvertebrate

cover in the spring-cleared plots was only about half that of the controls (63 vs. 121 percent).

Bare rock accounted for a relatively large area of the plots in fall 1992 (19 percent), rock and n

shell debris for much less (6 and 2 percent, respectively).

Overall, total macrophyte cover in the spring-cleared plots, although somewhat greater than 1

controls (32 vs. 8 percent), was still relatively low, with the cover of most taxa (12) being less

than 2 percent each. Only 3 of the 15 macrophytes observed in the spring-cleared plots were 1

somewhat common: the crustose red algae Petrocelis sp(p). (8 percent), the articulated coralline II

alga Bossiella pIumosa (7 percent), and the tufted red alga Endocladia muricata (4 percent).

I

The most abundant motile macroinvertebrates based on density were small limpets, Lott/a sp(p). I

(39010.1875 m2). Next in abundance were the littorine snails L/ttor/na scutuIata/plena (86),

followed by the limpets "CoUisella" scabra (33) and Lott/a digitalis (16), the predatory snail •

NucelIa emarginata (6), and the limpets Lott/a paradigitalis (5) and Lott/a pelta (3). Total I

grazer density included 447 limpets, 86 littorine snails, 2 chitons, 1 Tegula snail, and 1 sea

urchin. I

Comparison of species richness with previous years (Kinnetic Laboratories, Inc., 1992) indicated

that the number of macroinvertebrate taxa in fall 1992 (17) was similar to most previous fall n

sampling periods (range 12 - 19, Table A-11). The number of maerophyte taxa observed in fall

1992 (15) was also similar to that observed in (Kinnetic Laboratories, Inc., 1992) fall 1986-1989

(15 - 18), but was much higher than in fall 1985 (8), which was observed only 7 months after n

clearing. For all fall sampling periods combined, a grand total of 23 maeroinvertebrate and 32

macrophyte taxa were observed in the Mytilus spring-cleared plots at Sea Ranch.

From 1985-1992, total macrophyte cover varied from a low of 32 percent in 1992 to a high of 63 II

percent (Table A-11). Although changes in total macrophyte cover showed no obvious trends, m

two years, 1986 (38 percent) and 1992, were noticeably lower than the others. Total I

!

36 I
I Table 10. Macrophyte, macro/nvertebrate, and substratum abundances in the Mytilgs assemblage

' cleared plots at Sea Ranch during fall 1992. _

Taxon/Substratum Spring- Mean Cleared S.D. z Fall- MeanClearedS.D.

I Macrophytes - Cover (Percent)

Petrocelis sp(p). 7.8 6.9 0.6 1.0

I Bossiella Endocladiaplumosa muricala 7.2 4.4 2.6 3.5 18.9 3.9 3.5 5.4

Ana//pus japon/cus 1.7 2.9

I lMastoca r/daea rsp/endens pus papi//atus 1.7 1.7 1.7 1.7 53.0.3 4.4 1.7

Brown Crusts 1.1 1.9 2.2 3.9

Oadophora co/umb/ana 1.1 1.0 10.0 7.3

I Polysiphonia hendryi 6.1 2.6

1.1 1.0

Red crusts 1.I 1.9 1.7 2.9

Ir/daea heterocw/m 0.6 1.0

I Phaeostrophion Odontha/m floccosa irregulare 0.6 0.6 11.0.0 3-.9 6.7

P/ocam/um v/o/aceum 0.6 1.0 -

i OZva sp(p). 0.6 1.0 -

BossieIla sp(p). 1.I 1.0

Cora///na vancouver/ens/s 1.7 1.7

Leathesia diffonnis 0.6 1.0

I Total Macrophyte Cover 31.9 59.0

I Macroinvertchrates - Cover (Percent)

Myt//us ¢tz//fom/anus 27.8 17.7 8.9 3.9

i Ba/mut O s g/andu/a 16.7 18.6 6.7 8.8 zthanm/us sp(p). 13.9 21.2 7.8 9.5

Lott/a d/g/ta//s 2.2 1.9 1.7 2.9

Anthopleura elegantissinm 0.6 1.0 -

I Nuce//a emarg/n_a 0.6 1.0 - Paguras sp(p). 0.6 1.0 -

Pisaster ochraceus 0.6 1.0 -

I L/trot/no "Co///se//ascutu/ata/p/ena " scabra 0.6. 1.0 1.0

Lott/a pe/ta 0.6 1.0

i Nuttallina californica 0.6 1.0 eoU.s t.7 1.7

Tetraclita rubescens 0.6 1.0

I Total MacToinvertchrate Cover 63.0 29.8

I

I 37
I

Table 10. Macrophyte, macroinvertebrate, and substratum abundances in the Mytilus assemblage I

cleared plots at Sea Ranch during fall 1992 1 (continued).

Taxo_Substra_mn MSpring-Cl ean eS.D. aredz MFall- eanCleareS.D. d I

Macr_nve_ebrmes -Densay _o.I0.1875 m2) l

Lot_ sp_). 389.6 154.9 I00.0 103.3

_uonna scutu_p_na 86.0 141.0 23.2 20.0 1

"ColliseUa" scabra 33.2 24.8 10.3 9.2 I

Lot_a _g_a_s 15.8 4.4 27.5 18.6

Nucella emarginata 5.7 2.5 3.0 1.0 •

Lottia paradigitalis 4.8 7.4 4.1 5.4

Lottia pelta 2.7 1.5 16.2 23.8

Nuttallina californica 1.3 0.6 2.0 1.7 •

Strongylocentrotus purpurams 0.7 0.6 0.3 0.6 1

Mopaliamuscosa 0.3 0.6 -

Tegula funebralis 0.3 0.6 1.3 1.5 i

Leptaster/a sp(ps). - 0.3 0.6 •

Lottia limatula - 0.3 0.6

Nemenea, unbent. - 0.3 0.6

I

Total Number of Macrophyte Taxa 15 13 I

ToUd Number of Macroinver/ebrate Tan 17 18

Total Number of A_ Taxa 32 31 •

Substrata - Cover (Percent) I

!

Bare Rock 19.4 9.6 24.4 2.6

Rock 6.1 1.0 25.6 20.0 •

Shell Debr_ 1.7 1.7 3.9 6.7 1

I

i Damaremeansof _ee _o_ (n=3). Taxaandsubslralawilhineachcategov/are rankedaffordingrathehumansinthespriag- •

clearedplots,thenlistedalphabefica_ffthemeansareequal. Totalpercentcovercanexceed100percembecausemultiplelayerswere

sampled.A dash(-) indicatesthetexon/mbmammwasnotrecordedmtheplotsindicated.

z S.D. = StandardDeviation •

I

!

38 I
I macroinvertebrate cover was even more variable than macrophyte cover from 1985-1992. Macroinvertebrate cover ranged from a low of only 8 percent in 1985 to a high of 63 percent in

1992.

I

The results of the fall 1992 survey indicated that mussel abundance continually increased at Sea

Ranch. Compared to fall 1989 (6 percent, Table A-11), mussel abundance was substantially

I greater in spring 1991 (22 percent, Table A-12) and fall 1992 (28 percent). However, compared

to the control plots in fail 1992 (93 percent), mussel abundance remained low.

I Several other trends were also apparent. The abundance of the tufted red alga Endocladia

muricata increased steadily from 0 in fall 1985 to 15 percent in fall 1989, but was down to 4

I perce 12). nThe t inabfall und1an992; ce Endocladia of the barnacleabundance Balanus wglandula as also lowwas(6substanti percent)allyin shigher pring 1in991fall(Ta1992 ble A(I7-

percent) compared to previous fall sampling periods (range 0 - 8 percent). The limpet Lott/a

I digitalis declined by more than 85 percent from a peak density of 112 per 0.1875 m 2 in fall 1986 to a low of 16 in fail 1992. However, if some of the small Lott/a sp(p), observed in fall 1992

(390) were Lott/a digitalis, the decline in this species may be offset in future years as smaller size

I classes grow large enough for identification.

Based on comparisons between the Bray-Curtis index of similarity of control and spring-cleared

I plots, the spring-cleared plots had recovered 68 percent by fall 1992 (Table 4), and of

recovery

the Mytilus assemblage was continuing at a slow rate (Figure 4). Another indication of recovery

was the continued increase in mussel cover (percent), which was at its highest level in fall 1992.

I The increase in the of mussels from 59 in 1991 85 large density spring (Table A-5) to in fall 1992

(Table 7) also indicates that recovery was continuing. Based on the mean rate of recovery, which

i actually declined in fall 1992 to 0.55 percent per month (Table 7) from 0.82 percent per month in spring 1991 (Table A-5), complete recovery is probably years away.

i Fall.Cleared Plots

Compared to control plots at Sea Ranch in fall 1992, species richness was much higher in the

Myti maerop lushass ytees,mbwlasageobser fall-clear ved iendthple ofats.ll-cl Aeatotredal ofplo3t1s taxa, (Tableincl1u0)divsng. 1148inmacr theocoinvntro ertelsbr. atTehse and 13

number of maerophyte taxa was especially high in the fall-cleared plots (13 vs. 3), but the

I number of macroinvertebrates was also higher (18 vs. 11). Total macroinvertebrate cover was much lower in the fall-cleared plots (30 percent) compared to controls (121 percent), while total

maerophyte cover was higher in the fall-cleared plots (59 vs. 8 percent).

I Unlike both control and spring-cleared plots, the mussel Mytilus californianus was not the most

abundant taxon in the fall-cleared plots based on cover. Mytilus abundance was only 9 percent in

I fall 1992.

I

I 39
!

mm

The most abundant taxon in the fall-cleared plots was the tufted red alga Endocladia muricata II

(19 percen0, followed by the tufted green alga Cladophora columbiana (10 percent). The

I

barnacles Chthamalus sp(p). (8 percent) and BaIanus glandula (7 percent) were next in 1

abundance, followed by the filamentous red alga PoIysiphonia hendryi (6 percent), the fleshy red I

alga Iridaea spIendens (5 percent), the articulated coraUine alga Bossiella ptumosa (4 percent),

the branched red alga Odonthaliafloccosa (4 percent), the fleshy red alga Mastocarpus •

papilIatus (3 percent), and brown crusts (2 percent). Rock (26 percent) and bare rock (24 |

percent) accounted for one-half of the total substratum in fall 1992; shell debris accounted for an

additional 4 percent. I

mm

The most abundant motile macroinvertebrates based on density were small limpets, Lott/a sp(p).

(10010.1875 m2). The limpet Lottia digitalis was next in abundance (28), followed by the •

littorine snails L/ttor/na scutulata/plena (23); the limpets Lott/a peIta (16),"Collisella" scabra

(10), and Lott/a paradigitalis (4); and the predatory snail Nucella emarginata (3). Total grazer

density included 159 limpets, 23 littorine snails, 2 chitons, 1 Tegula snail, and 1 sea urchin. I

Comparison of species richness with previous years (Kinnetic Laboratories, Inc., 1992) indicated

that the total number of taxa increased gradually from a low of 20 in fall 1986 to 32 in fall 1989 II

and 31 in fall 1992 (Table A-13). The increase in species richness was especially true for m

macroinvertebrates, which increased from 12 in fall 1986 to 18 in fall 1992. Although this trend mm

was also true for macrophytes from fall 1986 (8) to fall 1989 (16), only 13 macrophyte taxa were •

observed in fail I992. For all fall sampling periods combined, a grand total of 23

I

maeroinvertebrate and 28 macrophyte taxa were observed in the Mytilus fall-cleared plots at Sea

Ranch. I

Overall, total maerophyte cover increased slightly from 1986-1992 (Table A-13). Macrophyte •

cover was lowest during the first 2 years of the study (35 and 34 percent, respectively) and was !i

higher in later years (54 - 59 percent, respectively), reaching its highest level in 1992. Total

maeroinvertebrate cover varied with no obvious pattern, from a low of 14 percent in 1986 to a •

high of 42 percent in 1988; total macroinvertebrate cover in 1992 was 30 percent.

The results of the fall 1992 survey indicated that mussel abundance continued to increase in the

fall-cleared plots at Sea Ranch, although at a much slower rate than in the spring-cleared plots.

Compared to fall 1989 (2 percent, Table A-13), mussel abundance was greater in spring 1991 (6

percent, Table A-12) and fall 1992 (9 percent). However, compared to control plots (93 percent),

mussel abundance remained very low. I

Based on comparisons between the Bray-Curtis index of similarity of control and fall-cleared I

plots, the fall-cleared plots had recovered 42 percent by fall 1992 (Table 4), and recovery of the

mm

Mytilus assemblage was continuing at a very slow rate (Figure 4). Another indication that these

plots were recovering was the large increase in the density of mussels from 13 in spring 199i

(Table A-5) to 37 in fall 1992 (Table 7). Based on the mean rate of recovery, which actually

declined slightly in fall 1992 to 0.41 percent per month (Table 7) from 0.66 percent per month in II

40 |
I spring 1991 (Table A-5), complete recovery is still probably years away. The mean recovery rate for the fall-cleared plots in fall 1992 was even lower than the spring-cleared plots (0.41 vs. 0.55

pereentJmonth), and the amount recovered was also lower (42 vs. 68 percent).

i 2. Endocladia/Mastocarpus Assemblage

I As discussed below, in fall 1992, the Endocladia/Mastoca_us assemblage in the control plots

had not substantially changed from previous surveys of these plots.

I AE total of 29 taxa, including 17 macrophytes and 12 rnacroinvertebrates, was observed in the ndocladia/Mastocarpus assemblage control plots at Sea Ranch during fall 1992 (Table 11).

Although the number of macrophyte taxa was only about 40 percent higher than

I macroinvertebrates, total macrophyte cover (131 percent) was substantially higher than macroinvertebrate cover (8 percent).

I Based on cover (percent), the most abundant taxon in fall 1992 was the tufted red alga

Endocladia muricata (48 percent), which was also the most abundant in spring 1991 (47 percent

- Table A-14). Next in abundance in fall 1992 was the fleshy red alga Mastocarpus papiUatus

(21 percent), by gardneri (1 percent), green alga followed the rockweed Fucus 8 the tufted

Cladophora columbiana (17 percent), the crnstose red algae Petrocelis sp(p). (5 percent), the

branched red alga Cryptosiphonia woodii (4 percent), the rockweeds Pelvetia-Pelvetiopsis sp(p).

I (3 percent), and the articulated coralline alga Corallina offtcinalis (2 percent). Cover of each of

the remaining nine macrophytes was less than 2 percent. Although bare rock accounted for only

7 percent of the substratumin fall 1992, a substantial amount of rock (32 percent) was observed.

Macroinvertebrates contributed very little to the total cover in the Endocladia/Mastocarpus

assembla 1992 wasgonl e coyntro 8 pelrcent, plots. andThe combined cover of the seven macroinvertebrates observed in fall the cover of all but one taxon, the sea starPisaster ochraceus (2

percent), was less than 2 percent each.

I The only abundant motile macroinvertebrates were small limpets, Lott/a sp(p). (75/0.1875 m2);

densities of the remaining six motile taxa were less than 2. Total grazer density included 79

I limpets; no other grazers were observed in fall 1992.

i . Comparison of species richness with previous years (Kiunetic Laboratories, Inc., 1992) indicated

II that the number of macrophyte taxa observed at Sea Ranch in fail 1992 (I7) was within the range

I

of that observed from fall 1985 to fall 1989 (range 13 - 17, Table A-15). The number of

macroinvertebrate taxa observed in fall 1992 (12) was also within the range of previous fall !

I 41

I
!

Table 11. Macrophyte, macroinvertebrate, and substratum abundances in •

the Endocladia/Mastocarpus assemblage control plots at Sea Ranch

I

dNg fsll 1992.1

S.dd |

Taxon/Su_ Mean _t_n

I

Macroph_es - _ver (pe_)

Endodadia muricata 48.3 11.7 !

Mastocarpuspapillatus 21.1 3.5

m

Fucus g_n 18.3 7.6

Cladophora columbiana 17.2 24.1 1

Petrocelis sp(p). 5.0 2.9

Oyptosiphonia woodii 3.9 4.2

Pelvetia-Pelvetiopsis sp(p). 3.3 2.9 •

Cora///na offic/na//s 2.2 3.9 |

Cora///na vancouvetiens/s 1.7 2.9

l_ea xp/endens 1.7 2.9 I

_ _). 1.7 2.9 1

U/va sp(p). 1.7 1.7 E1

Brown crusts 1.1 1.0

Polysiphonia hendryi 1.1 1.9 1

Po_yra _o_a 1.1 1.9

Crustos¢cor_Rn_, un_em. 0.6 1.0

Neon_mze_ k_x 0.6 1.0 •

TotalM_ Cover 1_.6

_ert_ - Cover(Percent) i

Pisaster ochmceus 2.2 3.9

Anthop/eum xanthogramm/ca 1.7 2.9 •

Anthopleura elegantissima 1.1 1.9

Chthanmlussp(p). I. 1 1.0

Ba/anus g_da 0.6 1.0 •

Lott/a pe/ta 0.6 1.0 l

,_/ffus ca//fot_ 0.6 1.0

Total_v_ Cover 7.9 1!

_v__ - _ _o./0.1_5 m_

Lo_a sp_). 75.0 41.0 I

"CoUisella"scabra 1.3 1.2

Lo_a _g_aSs 1.3 1.5 I

Lo_a pe_a 1.3 1.5 I Pisaster ochraceus i .0 1.7

Leptastersp(p). /as 0.3 0.6

NuceUaemarginata 0.3 0.6 I

42 |

I
I

I Table II. Maerophyte the Endoc/ad/, meroiuvertebrate _z/MasWcarpusassemblage , and substratum control plots abundances at Sea Ranch /n

during fall 1992 1(continued).

I Standard

Taxon/Substratum Mean Deviation

I Total Number of Macrophyte Tam 17

I Total Nmber of Macroinvertebrate Taxa 12

Total Nmber of All Tan 29

I Substrata - Cover (Percent)

Rock 32,2 9.2

I Baretack 7.2 4.2

i t Daaa_mmmofdm_pb_(affi3). Taxaand _mmawilhineach cac_goryare ranked

accon;li_ to the meam, thea listed_y ifthe meansare equal. Tolal percentcover can

exceed 100percent because_ layers were nml2ed.

I

I

I

I

I

I

!

I

I

43

I

I
!

am

salnpling periods (range 8 - 17), although the total number of macroinvertebrate taxa has been i

more variable than that of macrophytes. For all fall sampling periods combined, a grand total of

29 macrophyte and 27 macroinvertebrate taxa was observed in the Endocladia/Mastocarpus

assemblage control plots at Sea Ranch. i

The abundance and ranking of the more common taxa by abundance from fall 1985 through fall •

1989 was similar to that observed in fail 1992. Unlike the Mytilus control plots, comparatively II

little change occurred in the abundance of macrophytes from year to year, and total macrophyte

cover remained high (103 - 138 percent). As in fall 1992, the tufted red alga Endocladia •

muricata was the most abundant taxon in all fall sampling periods from 1985 through 1989

(range 41 - 58 percent). Similarly, the fleshy red alga Mastocarpuspapillatus (range 13 - 23

percent), the rockweed Fucus gardneri (range 10 - 25 percent), and the tufted green alga It

Cladophora coIumbiana (range 9 - 13 percent) were among the four taxa with the greatest cover,

although their ranking varied somewhat from year to year. The only exception was fall 1988,

when cover of the rockweeds Pelvetia-PeIvetiopsis sp(p), was slightly higher than Cladophora i

columbiana (12 vs. 11 percent). Except for the crustose red algae Petrocelis sp(p). (range 3 - 10 m

percent), and the rockweeds Pelvetia-Petvetiopsis sp(p). (range 0 - 12 percent), cover of the Ill

remaining 23 taxa was low from fall 1985 through 1989, and not all taxa were observed in every i

i

year.

As in fall 1992 (8 percent), total macroinvertebrate cover was also very low from fall 1985 g

through fall 1989 (range 7 - 16 percent). The sea anemone Anthopleura elegantissima (0 - 9

percent) and the barnacles Chthamalus sp(p), and Balanus g/andu/a (0 - 7 percent) were usually •

the taxa with the greatest cover, although their ranking varied from year to year. Cover of other |

taxa was low (<2 percent), and not all taxa were observed in every year.

Limpets were usually the most abundant (no./0.1875 m2) motile maeroinvertebrates from fall i

1985 through fall 1989. However, their total density was highly variable from year to year (range

30 - 174), and in 1988 the littorine snails L/ttor/na sp(p), were more abundant than limpets (101 i

vs. 30). n

A comparison of the EndocladialMastocarpus control plots from 1985-1992, using the Bray- i

Curtis index of similarity, indicated that in fall 1992 the EndocladiaiMastocarpus assemblage

control plots were about as similar to one another as they had been in most previous surveys but

were more similar to each other than in spring 1991 (Figure 5). I

!
I
I

i

C. Pescadero Rocks i

1. Mytilus Assemblage i

Symam

As discussed below, in fall 1992, 7 to 7 1⁄2 years after clearance, neither the spring- nor fall- i

cleared plots in the Mytilus assemblage at Pescadero Rocks had fully recovered. This was based

on a comparison of the Bray-Curtis index of similarity of the cleared plots relative to controls in •

fall 1992 (Figure 6) and on visual comparisons. The spring-cleared plots were 68 percent

recovered, and the fall-cleared plots were 42 percent recovered (Table 4). However, the plots

were more similar to the control plots than in previous sampling periods, indicating that recovery i

was continuing.

Macroinvertebrates were much more abundant than macrophytes in the Mytilus assemblage

controlplotsduringthefall1992survey(Table12).Of the17taxaobservedintheMytilus i

controlplots,13weremacroinvertebraand tes4 weremacrophytes.Also,totamlacroinvertebrate

m

cover was very high (126 percent), whereas total macrophyte cover was low (6 percent), i

The most abundant taxon in the mussel plots based on cover (percent) was the mussel MytiIus

californianus, which covered a very large portion (81 percent) of the substratum (Table 12). I

These mussels were generally medium in size (about 5 cm) and did not appear to be i

multilayered. Also abundant in the plots were four barnacle taxa: Balanus glandula (I 7

percent), Tetraclita rubescens (16 percent), Pollicipes polymerus (6 percent), and Chthamalus •

sp(p). (4 percent). Since barnacles were often attached to mussel shells, total maeroinvertebrate l

cover was very high (126 percent).

i

Only a small portion of the mussels or substratum had macrophyte cover (6 percent), and no large 1

macrophytes were common in the plots (Table I2). The most common rnacrophyte taxon was

green algae GATGOR (3 percent), which included no large macrophytes, but may have included i

some juvenile macrophytes. The remainder of the macrophyte cover (3 percent) was from three

red algal taxa: erustose eorallines, the tufted red alga Endocladia muricata, and the fleshy red

alga lridaea splendens. Rock accounted for 3 percent of the substratum in these plots, i

1

Although limpets only covered a small amount of the substratum (2 percent), they were the most

abundant motile macroinvertebrates based on density (no./0.1875 m 2, Table 12). The most 1

abundant limpet was "ColIisella" scabra (33), followed by Lott/a limatuIa (12), Lottia digitalis

1

(10), and Lottia pelta (8). The littorine snails Littorina scutulata/pIena occtmva] in small ==

numbers (19) considering the potential for these taxa to reach a very high density. The chiton I

NuttaUina californica occurred at a very low density (2). Total grazer density in these plots

included 66 limpets, 19 littorine snails, and 2 chitons. Ii

46 I

I

I

Table 12. _croph_e, mac_ve_rate, and substratum abundances m •

the Mytilus assemblage control plots at Pescadero Rocks during fall

1992.1

m

Tax_Su_am_m Mean _mfion

i

Macro_es - Cover (percent) 1

GATGOR 2.8 4.8 n

crus_se co_s, unident. 1.7 2.9 U

Endocladia muricata 0.6 1.0

Iridaeasplendens 0.6 1.0 n

u

Total M_m_ _ver 5.7

Macroinvertebrates - Cover (Percent) I

Myt//us ca//for_/wms 80.6 16.8

Ba/anus g/andu/a 16.7 3.3

Tetraclita n_.scens 16.1 6.3

PoUicipes pobymerus 6.1 6.3

Chthama/us sp(p). 4.4 2.6 •

"ColliseUa" scabra 1.1 1.9 II

Lottia pelta I. I 1.0

Total Maero_rtebrate Cov_ 126.1 n

I

"_e_" s_ra 33.3 8.7 I

_o_-_ sam_m_m 19.1 19.3

Lott/a//mam/a 12.3 10.4 •

Loa/ad/gitaUs 9.8 4.0 m

Lm_ 8.4 4.3

Lm_ _). 2.1 3.6 1

N_tallinacalifornica 2.0 3.5 l

Lon/apara_g/taUs 1.3 0.6 I

Tetal Nmaber of Macrophyte Tan 4 n

U

Total Number of Macroinvertebrate Taxa 13

Total Number of All Tan 17 1

Substratum - Cover (Perceat)

Rock 3.3 5.8 II

Dataaremeansof lta'eeplots(nffi3).Taxaandmbsualawilkinea_ categoryareranked I

accordingmfix:mmms_, ac1'limx _ all_m_:_fy ff tl_ me.artsarce_luM.Totalpercemcovercan

exceed100percentbecause_ layersweret,ampled.
I For all fall sampling periods combined, a grand total of 20 macrophyte and 21 macroinvertebrate taxa was observed in the Mytilus control plots at Pescadero Rocks (Table A-16). Comparison of

species richness in these plots from 1985 to 1992 indicated that total species richness during the

I fall sampling periods declined substantially from 1985-1992. KLI observed 29 taxa at the start of

their study in fall 1985, and only 20 taxa in fall 1989 during their last fall sampling period.

Species richness increased in spring 1991 to 24 taxa (Table A-17), but declined by fall 1992,

I only taxa were (Table 16). was primarily to a

when 17 observed A- This decline due decrease in

macrophyte taxa from 13 to 4 during the 1985-1992 sampling periods.

I In fall 1992, taxa abundances were similar to the last fall visit in 1989, but abundances during

these two surveys were very different from what they were in 1985 at the start of the study (Table

Athe-16greatest ). The cover most othrbvioous ughout chanthege stuwasdy,initsthecover mussateltheMytilus start. ofAthe lthoustudy gh Minytilus fall 1985 consistently was had

relatively low (30 percent). Mussel cover increased over time, reaching its highest fall level in

! I fall 1989 (86 percent), and remained high during the fall 1992 sampling period (81 percent).

Kiunetic Laboratories, Inc., (1992) suggested that these control plots may have had unusually low

I densities of mussels at the start of the study due to a previous natural disturbance, and that the plots initially may have been at an intermediate level of succession. By 1989, it appeared that

these plots had mussel cover similar to other sites in this study. This trend continued in 1992,

I and these control plots appeared to be in a late stage of succession. However, the large variability of the Mytilus assemblage at this site over time is an indication that changes to this

assemblage are likely to occur in the future, and that the intertidal community is dynamic.

I Several other changes in the assemblage over time were consistent with the increase in mussel

cover. During 1985-1992, total macrophyte cover changed substantially (Table A-16).

I Macrophyte cover was high (64 percent) decreased over until reaching in 1985 and time its

lowest fall level (6 percent) in 1992. Half of this decline was due to a decrease in total coralline

I algal macrophyt coverefrospecies m 33 percent in fall 1985 to 2 percent in fall 1992. Further, as discussed above, richness in these plots during the fall sampling periods declined from 13 to 4

from I985-1992. Thus, as mussel cover increased, total maerophyte cover and macrophyte

i ric thehnmaerophytes ess decreased,settled indicaontingthe that mussthels. ere wNoas nless merosubs phytetratcon umsfisoter nthetly macro had the phytegreate s andst cothavterfewfromof

1985-1992.

I Some taxa were at their highest or lowest abundances during the study in fall 1992 (Table A-16).

The articulated coralline alga Bossiella plumosa was at its lowest cover (0 percent), whereas the

I barnacles Balanus glandula and Tetraclita rubescens were at their highest cover (17 and 16 percent, respectively). Further, the limpet "CotIiseUa" scabra and the chiton Nuttallina

californica were at their lowest densities (33 and 2/0.1875 m2,respectively), whereas the littorine

I snails/.,/ttotina scutulata/plena and the limpet Lottia pelta were at their highest densities (19 and

8, respectively). These changes were also consistent with the increase in mussel cover over time.

Since barnacles and the limpet Lottia pelta were often attached to mussels, as the cover of !

49

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mussels increased so did the number of barnacles and the limpet Lottia pelta. The decline in the 1

other limpet and chiton taxa may have been due to the lower availability of rock or macrophytes, m

or these taxa may have been present but not visible within the densely packed mussel

assemblage. I

A comparison of the Mytilus control plots from 1985 to 1992, using the Bray-Curtis index of •

similarity, indicated that in fall 1992 the Mytilus assemblage control plots were more similar to I

one another than they had been at the startof the study in spring 1985 (Figure 6).

Spring-Cleared Plots I

During the fall 1992 survey of the spring-cleared plots, both macrophytes and macroinvertebrates •

were abundant. A total of 28 taxa was observed: t2 macrophytes and 16 macroinvertebrates

(Table 13). Total macrophyte cover (59 percent) and total macroinvertebrate cover (65 percent)

were also very high. i

The most abundant taxon based on cover was the musset MytiIus californianus (36 percent),

followed by the articulated coralline alga BossieUa plumosa (28 percent, Table 13). Other 1

abundant macrophytes were the articulated coralline alga Corallina officinalis (7 percent), the

branched brown alga Analipusjaponicus (6 percent), crustose corallines (6 percent), and the Ill

tufted green alga Cladophora coIumbiana (4 percent). Two barnacle taxa were common, I

Balanus glandula (15 percent) and Tetraclita rubescens (6 percent). The chiton Nuttallina

u

californica (3 percent) and the barnacles Chthamalus sp(p). (3 percent) were less abundant based m

on cover. Rock accounted for 6 percent, and bare rock accounted for 3 percent of the substratum I

in theseplots.

The most abundant motile macroinvertebrates based on density were the littorine snails L/ttor/na I

scutuIata/plena (48/0.1875 m2),followed by the limpet "CoIlisella" scabra (42, Table 13). The

chiton Nuttallina californica was the next most abundant maeroinvertebrate and occurred in •

fairly high densities for this taxon (29). Also common were the limpets Lott/a sp(p). (13) and II

Lott/a I/matu/a (9). Less common were the limpets Lottia pelta (5), Lottia paradigitaIis (3), and

Lottia digitalis (3). Total grazer density in these plots included 75 limpets, 48 littorine snails, I

and 29 chitons. U

For all fall sampling periods combined, a grand total of 35 maerophyte and 23 macroinvertebrate I

taxa was observed in the Mytilus spring-cleared plots at Pescadero Rocks (Table A- 18). A

comparison of these Mytilus plots from 1985-1992 indicated that species richness in fall 1992

(28) was similar to previous fall surveys (range 23 - 32), but up slightly from that in the 1989 I

survey (26). Species richness in fall 1992 was the same as spring 1991 (28, Table A-19). II

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50 I
Table 13. Macrophyte, macroinvertebrate, and substratum abundances in the Myt//us assemblage cleared plots at Pescadero Rocks during fall 1992:

I Taxon Spring-Cleared Fall-Cleared /Substratm Mean S.D. 2 Mean S.D.

I Maerophytes - Cover (Percent)

Bossiella plumosa 27.8 26.4 30.6 25.5

I Ana/ Cora///na /pus jtoffic/na// q_on/cuss 7.2 6.1 7.5 4.8 16.7 1.7 20.2 5.8

Crustose corallines, unident. 6.1 6.7 8.9 6.3

I Oadophora co/umb/ana 3.9 6.7 2.2 2.6

Cora///na vancouver/ens/s 1.7 2.9 2.2 2.6

Pelvetia-Pelvetiopsis sp(p). 1.7 2.9 1.1 1.9

lr/daea sp/endens 1.I 1.9 3.3 4.4

I P/ocam/um GATGOR v/o/aceum 1.1 1.9 - 0.6 1.0

Mastocarpus papiUams 0.6 1.0 4.4 6.3

I Ra/ [//vafs/asp(p). sp(p). 0.6 1.0 27.82 13.9.5

Po/y_phonm hendryi 1.1 1.9

i Rhodoglossum affine 1.1 1.9

Co/pmnen/a sp. 0.6 1.0

Egregia menziesii 0.6 1.0

Endoc/ad/a mur/cata 0.6 1.0

I Petrocelis sp(p). 0.6 1.0

Total Macrophyte Cover 58.5 85.7

Macroinvertebratm - Cover (Percent)

i Myt//us ca//forn/anus 36.1 25.9 t7.8 19.3 Ba/anus g/andu/a 15.0 7.3 7.2 5.4

Tetraclita rubescens 6.1 4.2 5.6 6.9

Nuttallina califoraica 3.3 2.9 3.9 6.7

I _ sp(p). 2.8 3.5 - PoUic_ves polymerus 0.6 1.0 1.7 1.7

Porifera, unident. 0.6 1.0

I LLtottia mta paradig pelta italis 0.6 0.6 1. 1.00

TotalMacroinvertebrate Cover 64.5 37.4

Macroinvertebrates - Density (No.10.1875 _)

L/tr "Co///ot/ se//ahascutu/at " scabraa/p/ena 441.8 7.9 46.1 4.3 128..15 3.5.46

NuUallina californica 28.7 17.0 30.0 27.6

I Lott/a sp(p). 12.5 10.8 10.4 13.0

| 51

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Table 13. Macrophyte, macroinvertebrate, and substratum abundances in the Mytilus assemblage •

cleared plots at Pescadero Rocks during fall 1992 _ (continued). u

Taxon/Substratum Spring-Cl Mean eS.D. ared_ Fall-Cl Mean eareS.D. d I

Macroinvertebrates - Density (No.I0.1875 n_) l

Lott/a//matu/a 8.5 12.2 2.4 4.2 U

Lott/a pe/ta 5.1 2.8 7.0 10.4 1

Lottia paradigitalis 3.0 3.6 6.1 8.9 m

Lottia digitalis 2.7 3.8 19.2 26.6

Fissurella volcano 0.3 0.6 0.3 0.6 •

Lottia gigantea 0.3 0.6

Total Number of Macrophyte Taxa 12 17 1

[] Total Number of Macroinvertebrate Taxa 16 13

Total Number of All Tan 28 30 I

Substrata - Cover (Percent)

mm

Rock 6.1 5.1 2.2 1.9 I

Bare rock 2.8 3.5 7.2 2.6

Shell debris 0.6 1.0 l

L Dataaremeansof threeplots(nffi3).Taxaandsul_tralawilhineach_uegmyarnmk e edacconiingtothemeaminthesp_-

clearedplo_sth, enlistedalphabeticallifythemeansaveequal. TotalpercentcovercanexceedIG0percentbecausemultiplelayerswere •

sampled.A dash(-)indkatesthe taxon/mbstratumwu nm_cordedintheplotsindicated. I

2 S.D. : Sta_a_ D_i_ion

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l However;betweenfall1985andfall1992,total macrophytecoversubstantially declined(from I03to59percent,TableA-18)andtotamacr l oinvertebrcaovteersubstantially increased(from5

to65 percent).Thesechangeswereconsistewnitthrecoveroyftheseplots,sincethecontrol

l plots a greater cover macrophytecover.

had much totalmacroinvertebrate than

Also, the abundances of many taxa had substantially changed from what was observed during fall

I surveys from 1985-1989 (Table A-18). In particular, the mussel MytiIus californianus steadily

increased after the plot was cleared in 1985, reaching its highest cover (36 percent) in fall 1992.

i This was much higher than during the last fall survey in 1989 (21 percent), and slightly higher

than during the last survey in spring 1991 (30 percent, Table A-19). Other taxa at their highest

abundance in fall 1992 included the barnacle Balanus glanduta (15 percent, Table A-I8), the

I arti pereen culated 0, thecocrhit alloinen Nut algtaIt a Coinarallcalif ina ornofficinal ica (3isperc (7 percent ent), the), bthearnacbarnacl les Chthamatus e Tetraclita sp(p rubesc ). (3ens (6

percent), the littorine snails L/ttor/na scutulata/plena (48/0.1875 m2), and the limpet Lott/a

I lima splendens tula (9(/10.1per87c5ent)mS,).theTaxgreen a at alg theirae lGowATGest OabRundance (I perceinntcluded ), the memb the flesranhyousredgralgeean Iridaea algae UIva

sp(p). (0 percent), the filamentous red alga Polysiphonia hendryi (0 percent), small limpets Lott/a

I sp(p). (13/0.1875 mS),and the limpet Ionia digitalis (310.1875 mZ). Although total limpet

density sharply increased after the plots were cleared, reaching its greatest fall level in 1986

(170/0.1875 mS), the total density during subsequent surveys was highly variable, and there was

I no clear pattern.

In addition to the change in mussel cover discussed above, several other large changes in taxa

I abundances occurred between the last two fall In all of the abundant surveys. particular, more

macrophytes in fall 1989 decreased in 1992 (Table A-18). The decline in total coralline algal

cover was particularly large, from 63 to 43 percent. Most of this was due to a decline from 42 to

I 28 percent cover of the articulated coralline alga BossieUa plumosa. This decline in coralline

algal cover as mussel cover increased was consistent with the same pattern noted in the control

i plot the sfleshy . ThereredwalgasaalIrida so aealargesplendens drop (from . In 12additi to on1 perc , declines ent) in inthethespdering-c nsitley ared (no/0.187 plots5 inmco2)voerf of

several limpets, particularly "Collisella" scabra (78 to 42), occurred between fall 1989 and fall

I fall 1992.1989In ctoontrast, 48 in fall the 1992. density of the littorine snails L/ttor/na scutulata/plena increased from 0 in

l indicated Comparithsonatothfthe sepBrinrayg-c-leCaruerti dndpslotsexohadfsimil not full arity yofrectohevesreprd iafte ngr-clea 71⁄2 yeaplrerots sd(toFigcon ure tro 6). ls

However, the plots had recovered 68 percent (Table 4). Also, the spring-cleared plots were more

I similar to the control plots than in previous sampling periods, indicating that recovery was continuing (Figure 6). Another indication that these spring-cleared plots were recovering was the

large increase in the density of mussels, from 186 in spring 1991 (Table A-5) to 247 in fall 1992

I (Table 7). Recovery appeared to be occurring through both encroachment and settlement of

mussels. As noted by Kinnetic Laboratories, Inc. (1992), the higher recovery at this site

i compared to other sites (especially for the spring-cleared plots) may have been an artifact of

53

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I

comparing these cleared plots to control plots that were at an intermediate level of succession, i

This may have been less important in fall 1992, when the control plots appeared to have been in a

late stage of succession, i

It was not possible to determine how long recovery will take. However, since the recovery rates

in both fall 1992 (0.75 percent/month, Table 7) and in spring 1991 (0.69 percent/month, Table A- •

5) were very low, recovery is expected to be slow. 1

Fall-Cleared Plots I

During the fall 1992 survey of the fail-cleared plots, both macrophytes and macroinvertebrates

were abundant. A total of 30 taxa was observed, including 17 macrophytes and 13 i

macroinvertebrates (Table 13). Total macrophyte cover (86 percent) and total macroinvertebrate []

cover (37 percent) were also very high, although rnacrophyte cover was much higher than

macroinvertebrate cover. I

The mussel MytiIus californianus was not the most abundant taxon based on cover (Table 13). II

Its relatively low cover (18 percent) was one obvious indication that these plots had not i

recovered very much. The most abundant taxon was the articulated coralline alga BossielIa

i

plumosa (31 percent). Other abundant taxa were the articulated coralline alga CoraUina i

officinalis (12 percent), erustose corallines (9 percent), the membranous green alga Ulva sp(p). (8 i

percent), the branched brown alga Analipusjaponicus (7 percent), the barnacles Balanus

gIandula (7 percent) and Tetraclita rubescens (6 percent), the chiton Nuttallina californica (4 []

percent), and the fleshy red alga Mastocarpus papillatus (4 percent). Less abundant were the 1

fleshy red alga lridaea splendens (3 percent), the tufted green alga Cladophora columbiana (2

percent), the articulated coralline alga Corallina vancouveriensis (2 percent), and the crustose •

brown algae Ralfsia sp(p). (2 percent). Bare rock accounted for 7 percent, and rock accounted I

for 2 percent of the substratum in these plots.

m

The most abundant motile macroinvertebrate based on density was Nuttallina californica, which i

occurred in high densities for this taxon (30/0.1875 mz,Table 13). Also common were the

limpets Lottia digitalis (19), "Collisella" scabra (19), Lott/a sp(p). (10), Lottia peIta (7), and i

Lottia paradigitalis (6). Total grazer density in these plots included 63 limpets, 30 chitons, and 2

littorine snails. Since this was similar to the spring-cleared plots, grazing pressure probably was

not a reason for the slower recovery rate of these plots, i

I

For all fall sampling periods combined, a grand total of 26 macrophyte and 25 macroinvertebrate m

taxa was observed in the Mytilus fail-cleared plots at Pescadero Rocks (Table A-20). A •

comparison of these Mytilus plots from 1986-1992 indicated that species richness in fail 1992

i

(30) was similar to that in previous fall surveys (range 27 - 31) and the same as fall 1989 (30),

but down from spring 1991 (38, Table A-19). i

I

54 I
I H157owetover, 86 percent, between Table fall 19A-20) 86 andandfailtotal 1992, macroinvertebrate total macrophyte cocoverversubstantially substantially increased declined (from (from 2

to 37 percent). These changes were consistent with recovery of these plots, since the control

I plots had a much greater total macroinvertebrate cover than macrophyte cover. Also, the abundances of many taxa had substantially changed from what was observed during fall

surveys from 1986-1989 (Table A-20). In particular, cover of the mussel Mytilus californianus

I increased after the cleared in 1985 and reached its 18 in steadily plot Was highest cover ( percent)

fall 1992. This was much higher than during the last fall survey in 1989 (6 percent), and higher

than during the last survey in spring 1991 (11 percent, Table A-19). Other taxa at their highest

I abundance in fall 1992 included the articulated coraUine alga Corallina officinalis (12 percent,

Table A-20), the barnacle Balanus glandula (7 percent), the barnacle Tetraclita rubescens (6

i percent algae Ralf ), the sia chit sp(p). on Nutta (2 perce Uinant),calif theornica limpet (Lottia 4 percent digitalis cover;(1930/0.1875 /0.1875 m2), m2),and the the crustlimpet ose brLottia own

limatula (2/0.1875 m2). Taxa at their lowest abundance were the fleshy red alga lridaea

I spl Egregia endensmenziesii (3 percent), (1 perce the tufted nt). Total greenlimpet alga Clad density ophoreached ra columbiana its highest(2 fail percelevel nt), inand1988 the kelp

(152/0.1875 m2) and gradually declined in subsequent surveys, reaching 64 in fall 1992.

I In addition to the change in mussel cover discussed above, several other large changes in taxa

abundances occurred between the last two fall surveys (Table A-20). In particular, the kelp

I Egregia menziesii decreased from 21 to I percent cover, the fleshy red alga Iridaea splendens decreased from 18 to 3 percent cover, and the tufted green alga Cladophora columbiana

decreased from 13 to 2 percent cover. However, unlike in the spring-cleared plots, total coralline

I algal cover did not change from 1989 (54 percent) to 1992 (53 percent). Coralline algal cover

may not have declined with increasing mussel cover, as occurred in the control and springcleared plots, because mussel cover was still very low (18 percent) in the fall-cleared plots. In

I addition, between fall 1989 and fall 1992, the 1875 mz) of the "Cotlisella"

density (no/0. limpet

scabra decreased substantially (72 to 19). This was a greater drop than in the spring-cleared

plots. In contrast, the density of the chiton Nuttallina californica increased from 15 in fall 1989

I to 30 in fall 1992.

i Com indicated parisothat n ofthethefall-cleared Bray-Curtisplointsdexhadofnsimilarity ot fully recov of the eredfall-cl aftereared 7 yeaprslo(Figure ts to the6), conandtrolnone plotsof

the individual plots were close to recovery (Table 4). Also, these plots had recovered much less

I than and were the sprin mo g-cleared plots discussed above. However, the plots had recovered by 42 percent, re similar to the control plots than in previous sampling periods, indicating that

recovery was continuing. Another indication that these fall-cleared plots were recovering was

I the large increase in the density of mussels, from 55 in spring 1991 (Table A-5) to 126 in fall 1992 (Table 7).

I Although total recovery time could not be determined, these plots appeared to be recovering very

slowly. The recovery rates for these plots in spring 1991 (0.38 percent/month, Table A-5) and

fall 1992 (0.50 percent/month, Table 7) were both very low. Also, these plots appeared to be

I

55

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recovering slower than the spring-cleared plots. The recovery rate in fail 1992 (0.50 m

percent/month, Table 7) was slightly lower than the recovery rate for the spring-cleared plots

m

(0.75 percent/month). Also, the density of mussels in these plots (I 26) was much lower than in 1

the

spring-cleared plots (247). m

2. Endocladia/Mastocarpus Assemblage m

As discussed below, in fall 1992, the Endocladia/Mastocarp_ assemblage was similar to what it

had been during the fall 1989 survey, but both total macrophyte cover and total m

macroinvertebrate cover during these surveys were much lower than when the study began in

1985. Also, the abundances of several taxa had changed from previous surveys of this

assemblage, m

F.,ommI.PJo

In fall 1992, a total of 21 taxa was observed in the Endocladia control plots (Table 14). m

Although the numbers of macrophyte (12) and macroinvertebrate (9) taxa were not substantially

different, total macrophyte cover was very high in these plots (125 percent), whereas total m

macroinvertebrate cover was very low (2 percent). m

most abundant taxon based on cover was the tufted red alga Endocladia muricata, which m

The

covered half the substratum (50 percent, Table 14). In addition, the fleshy red alga Mastocarpus

papillams (24 percent) and the rockweeds PeIvetia-Pelvetiopsis sp(p). (21 percent) each covered •

a large portion of the plots. The rockweeds Pelvetia-Pelvetiopsis sp(p), typically were overlaying l

the tufted red alga Endocladia muricata or the fleshy red alga Mastocarpus papiIlatus, but

occasionally were overlaying rock or other taxa. Other common macrophyte taxa included the •

fleshy red alga Rhodoglossum aft-me (10 percent), the tufted green alga Cladophora columbiana I

(5 percent), and crustose corallines (5 percent). Less abundant were red crusts (3 percent) and

the membranous green algae Ulva sp(p). (3 percent). Rock accounted for a large amount of the m

substratum (24 percent), and bare rock accounted for a fairly large amount of the substratum (11

percent) in these plots.

Although macroinvertebrates only covered a small amount of the substratum,some motile m

macroinvertebrates were abundant based on density (Table 14). The most abundant motile

macroinvertebrates were the littorine snails Littorina scutulata/plena (103/0.1875 m2), followed I

by several taxa of limpets, including small Lott/a sp(p). (15), "ColliseUa" scabra (13), and Lottia m

digitalis (4). Unidentified Polyplacophora (chitons) occurred at low densities (4). Total grazer m

density included 103 littorine snails, 32 limpets, 4 chitons, and 1 Tegula snail. •

m

I

56 m
I Table 14. Macrophyte the Endocladia/Mastocarpus , macroinvertebrate, assemandblagesubstratu controlmplots abundances at Pescadinero

Rocks during fall 1992.t

I Standard

Taxon/Substratum Mean Deviation

I Macrophytes - Cover (Percent)

I Endocladia Mastocarpusmuricata papillatus 5023.9.0 9.2 6.0

Pelvetia-Pelvetiopsis sp(p). 21.1 I1.3

i Ritodoglosswn affine 10.0 7.6

Cladophora columbiana 5.0 3.3

Crustosecorallines,unidem. 5.0 6.0

Redcrusts 3.3 5.8

I U/va C-e/M/am sp(p). cou/ter/ 2.8 1.7 2. 1.99

Petrocelis sp(p). 1.1 1.0

I Brown Ou2etomor crusts pha//man 0. 0.66 1. 1.00

TotalMacrophyteCover 125.1

I Macroiavertebrates - Cover (Perceat)

I Ba/a "ColIisella" nus g/andu/a scabra 01..67 2.9 1.0

I TotalMacroinvertebrateCover 2.3

Maeroinvertebrates - Density (No.10.1875 riP)

I L/tror/na scum/am/p/ena 103.0 176.7 Lon/asp(p). 14.6 t5.7

"ColliseUa"scabra I3.1 15.7

zPolyplacophora, ,oa/a_g_ts unidem. 4.2 3.'_ 7.2 3.8

Tegulafunebralis 0.7 1.2

i Lep/doc_ona dem/em 0.3 0.6

" NuceUaemar#nata 0.3 0.6

Total Number of Macrophyte Taxa 12

I Total Nmber of Maeroinvertebrate Taxa 9

I Total Number of All Taxa 21

57

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Table 14. Macrophyte, macroinvertebrate, and substratum abundances in I

the Endocladia/Mastocarpus assemblage control plots at Pescadero

Rocks during fall 1992 _(continued).

Standard !

Taxon/Substratum Mean Deviation

Substrata - Cover (Percent) i

Rock Bare rock 24.4 10.6 8.4 5.1 I

t Dalaa_emeansofflueeplots(n=3). Taxaandsubstratawithineachcategoryareranked I

accordingto themeans,thenlis_ alphabeticallyifthemeansareequal.Totalpercentcovercan

exceed100peru becausemultiplelayerswen_sampled.

I

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58 |

I
I For all fall sampling periods combined, a grand total of 21 macrophyte and 17 macroinvertebrate taxa was observed in the EndocladiMMastocarpus control plots at Pescadero Rocks (Table A21). Comparison of these EndocIadialMastocarpus plots from 1985-1992 indicated that in fall

I 1992 species richness (21) was similar to that in previous fall surveys (range 21 - 25), but slightly down from 1989 (24) and slightly up from spring 1991 (20, Table A-22). In contrast, between

fall 1985 and fall 1992, large declines were observed for beth total macrophyte cover (198 to 125

I Table A-21 and total macroinvertebrate 12 to 2

percent, ) cover ( percent).

Also, the abundances of many taxa had substantially changed from what had been observed

I during fall surveys from 1985-1989 (Table A-2 I). The tufted red alga Endoctadia muricata

consistently had the highest cover in the control plots over time, but it ranged from 48 to 73

i percent. taxon, ranging The fleshy from red 24 toalg53a Mastocarpus percent, and was papillatus at its lowest was consistentl cover in yfalltheI992next(24mopercent). st abundantThe

rockweeds Pelvetia/Pelvetiopsis (21 percent), the littorine snails Littorina scutulata/pIena

(103/0.1875 m2), and unidentified Polyplaeophora (chitons) (4/0.1875 m2) were at their highest

I abundance in fall 1992.

I ChRockangdeclined es in the over amouallntfromof sub42stratum percentaltoso24weperc re oebse nt,rved and betwee shell debris n 198declined 5 and 19ove 92 r(Tabl all frome A-2113).to

0 percent. In contrast, bare rock increased from 1 percent to 11 percent between 1985 and 1992.

I However, comparison of the EndocladialMastocarpus control plots from 1985 to 1992, using the

Bray-Curti_ index of similarity, indicated that in fall 1992 the control plots were about as similar

I to one another as they had been in most previous surveys (Figure 7).

Comparison of the last two fall surveys, in 1989 and 1992, indicated that the abundances of most

I taxa were similar (Table A-21). In particular, cover of the tufted red alga Endocladia muricata

was 54 percent in 1989 and 50 percent in 1992. Also, cover of the fleshy red alga Mastocarpus

papillatus was 29 percent in 1989 and 24 percent in 1992. However, the density (no./0.1875 m2)

I of the limpet "Coltisella" scabra substantially declined in 1992, whereas the density of the

littorine snails Littorina scutulatalplena substantially increasedS.pecifically, the density of the

i limpet "ColliseUa" scabra was one-third as high in 1992 (13) as in 1989 (47), and the density of

the littorine snails L/ttor/na scutulata/plena was almost twice as high in 1992 (103) as in 1989

(57).

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I
I D. Point Sierra Nevada

i 1. Mytilus Assemblage Smem

I As of fall 1992, 7 to 71/2years after the initial clearings, total mussel cover remained below 20

percent at Point Sierra Nevada. The spring-cleared plots had recovered 55 percent, and the falli cleared control plots plots hthadanrinecove prerevioud 6s7saperc mpling ent (Table periods,4).whHowe ich invder,icates the plots that recove were rmoy wa re ssimil continuing ar to the

(Figure 8).

I Control Plots

I inOvthe erall,fall101992 macrsampling ophyte taxa period, and 21resulting maeroininveartespecies brate ritaxchness a were(total obsernumber ved at Poof intaxa) t Sieofrra31Nevada

(Table 15). Total macroinvertebrate cover (78 percent) was more than twice total macrophyte

I cover (35 percent).

Mussels (MytiIus californianus) predominated in the control plots in fall 1992, covering nearly

I two-thirds of the substratum (62 percent) (Table 15). Mussels in the control plots appeared to be relatively uniform in size, and mean length was visually estimated to be roughly 6-7 cm.

I The next most abundant maeroorganisms were articulated coralline algae, including Bossiella

plumosa (12 percent) and CoraIlina vancouveriensis (10 percent), and unidentified crustose

corallines (6 percent). The barnacles PoUicipes polymerus (6 percent) and Balanus glanduIa (3

I percent) were the next most abundant macroinvertebrate taxa. Bare rock accounted for 6 percent,

and rock for 2 percent of the substratum in the control plots.

Other than the coralline algae listed above, macrophytes contributed little to the total cover in the

Mytilus control plots (7 percent overall). The taxa observed included the filamentous red alga

I Pol sp(p)., ysiphotheniaarticulated hendryi, coralline the fleshyalgaredCorallina alga Rhodogl fficinalis ossum , atheffinecr,uthe stosecrubrown stose redalgaealgae Petrocelis

Cylindrocarpus rugosus and Ralfsia sp(p)., and green algae (GATGOR).

Limpets predominated numerically among the motile macroinvertebrates (Table 15). The most

abundant limpet taxa (in terms of density expressed as noJ0.1875 m2) were Lott/a pelta (25),

I Lottia digitalis (23), Lott/a paradigitalis (22), "ColliseUa" scabra (21), and small Lott/a sp(p).

(13). The littorine snails L/ttor/na scutuIata/plena and L/ttor/na keenae (6) and the chiton

NuttaUina californica (3) were the next most abundant grazers. Total grazer density included

I 104 limpets, 6 littorine snails, 3 chitons, and 1 sea urchin.

!

61

I
' I
I Table 15. Macrophyte, macroinvertebrate, and substratum abundances in the Myt//us assemblage control plots at Point Sierra Nevada

during fall 1992)

I Standard

Taxon/Substratum Mean Deviation

I Macrophytes - Cover (Percent)

I Bossie Cora///na Ua plumosa vancouver/ens/s 1110.0.7 t0.0 10.1

Cmstose corallines, unident. 6.1 7.9

I Polysiphonia Rhodoglossum hendryi affme 1. 1.77 2. 1.97

Cylindrocarpus rugosus 1.1 1.9

Cora///na offic/nu//s 0.6 1.0

i GATGOR 0.6 1.0 Petrocelis sp(p). 0.6 1.0

sa_/a sp(p). 0.6 1.o

I Total Macrophyte Cover 34.7

i Macroinvertebrates - Cover (Percent)

Myt//us cu/_orn/anus 62.2 6.9

Pollic_es polymerus 6.1 3.5

l Ba/anus glandu/a 3.3 4.4 Chthama_ sp(p). 1. t 1.9

/.aTff/aparad/g/ta//s 1.1 1.0

I Amhopleura Lottia gigameaelegamissima 00.6.6 1.0

lamia pelta 0.6 1.0

i Nutta///na ca/fromica 0.6 1.0 Phragmmopoma californica 0.6 1.0

5_rongy/ocentrot_ purpuratus 0.6 1.0

Tetraclita rubescens 0.6 1.0

I Total Macroinvenebrate Cover 78.0

I Macroinvertebrates - Dens/ty (No.10.1gT$ m")

Lott/a pe/ta 24.8 12.0

Lott/a d/g/ta//s 22.8 9.9

I Lott/a 21.9 32.8 "CoUiseUa"scabra 20.6 14.2

/am/a sp(p). 12.5 10.8

I Littorina NuttalIinascut californica ulma/plena 43.0.8 4.2 3.0

Linorina keenae 1.3 2.3

i Stmngy/ocentrmus purpuratus 1.3 2.3

63

I
i

i

Table 15. Macrophyte, macroinvertebrate, and substratum abundances in •

the Myt//us assemblage control plots at Point Sierra Nevada II

during fall 1992 1(continued).

Standard i

Taxo_Su_m Mean Deviation

I

Macroinvertebrates - Density (No.10.1875 mz) i

NuceUa emarginata 0.7 1.2 1

_ _m_ 0.3 0.6 1

Ocenebra circumtexta 0.3 0.6

Tegulo funebralis 0.3 06 l

To_ Number of Macroph_e Taxa 10

Total Number of Macroinvertebrate Taxa 21 I

m

Total Number of All Tan 31

I

Substratum - Cover (Perceat) i

Bare rock 6.1 3.5 •

Rock 2.2 1.0 1

She1 debrm 1.7 2.9

I

Damarememmof threeprom(n=3). Taxaandsubs_mwithmeachuuegorym'enmked

_ _ _e mmms,fl_-ni_¢d a_aHy ff_ mmmsare¢q_. Totalpercentcovercan I

©xc_d 100pe_m becam_nnflfip_layersweresampled.

I
I Species richness observed in the Mytilus control plots generally has increased over the course of

the study, from a tow of 19 taxa in fall 1986 to a peak of 31 in fall 1992 (Table A-23).

I Macroinvertebrate taxa accounted for most of this increase; 21 macroinvertebrate taxa

were

observed in 1992, compared to the 11-16 taxa observed during the fall surveys from 1985-1989

(Table A-23) and during the spring 199t survey (Table A-24). The 10 macrophyte taxa observed

I fell within the range observed during previous surveys (6-13). In all, 46 different taxa, including

25 macroinvertebrates and 21 macrophytes, were identified during fall surveys.

I Comparison of the results of the fall surveys conducted from 1985 through 1992 (Table A-23)

and of the survey conducted in spring 1991 (Table A-24) indicated that cover was similar

I betwe substantial en yeadecline rs, except to 62forpercent a temporary observedincrease betweenin muspring ssel c1991 over taond93fall percent 1992.inTt9his88decline and a was

also reflected in a decrease in total macroinvertebrate cover from 93 to 78 percent over this latter

I peseastar, riod. Pisa Theresteris ochraceus some evid.enTwo ce thatlargthis e Pisaster decreasewere maypresent be at least in onepartlofy theduecontrol to predaplots tion inbyfall the

1992. The mussels present in this plot were distributed in irregular clumps separated by swathes

I measuring10-20cm inwidth.A similarpatternwasobservedintheothercontrolplots.

Lesserdeclinewserealsoobservedforbarnacleand s overalllimpetdensities. The dccfinine

I barnacle abundance (from 21 percent in 1985 to 11 percent in 1992) may have been related to the decrease in mussels, which serve as attachment points for these sessile macroinvertebrates. The

limpet decline is attributable mainly to one taxon, Lott/a digitalis, whose observed density in fall

I 1992 (23/0.1875 m2) (Table A-23) was half that observed in fall 1989 (56) and in 1991 spring

(51) (Table A-24).

I In contrast to the decrease in macroinvertebrate cover, total macrophyte cover increased

substantially between spring 1991 and fall 1992, from 20 percent (Table A-24) to 35 percent

i co(Traballinle A-2 e algae 3). Most of this change was attributable to an overall increase in the abundance of

, which increased to 28 percent from a low of 2 percent observed in 1988.

I The plotsBwere ray-Cnmot'tiassindex similaroftosimilarity each othercalcul as the atedy haford thbeen e Mytitus in springplots1991, (Figure but were 8) showithin ws thathe t therange

of similarity recorded in previous years. The least similar control plots had a similarity of 61

I percent to one another (Table 4).

Spring-Cleared Plots

II== In fall 1992, 15 macrophyte taxa and 14 maeroinvertebrate taxa were observed at Point Sierra

Nevada, for a total (species richness) of 29 taxa (Table 16). Total macrophyte cover was 80

I percent in fall 1992; total macroinvertebrate cover was substantially lower at 22 percent. The predominant macroinvertebrate taxon in the spring-cleared plots in fall 1992 was Mytilus

cal_ornianus (12 percent) (Table 16). Two distinct size classes of mussels appeared to be !

65

!
m

Table 16. Macrophyte, macroinvertebrate, and substratum abundances in the Mytilus assemblage •

cleared plots at Point Sierra Nevada during fall 1992. I

i

Taxon/Substratum MSpring-Clear ean S.D. ed_ Fall-Cl Mean eareS.D. d i

Maerophytes - Cover (Percent) 1

Bossiellaplumosa 30.0 19.2 15.6 10.6 mm

Cladophora columbiana 18.9 27.0 9.4 14.9 l

Ulva _). 6.1 3.5 -

I

Egregia menziesii 5.0 5.0 -

_us j_mcus 2.8 1.9 1.1 1.9 •

C_ylindrocarpus rugosus 2.8 1.9 14.4 13.6

Endocladia muricata 2.8 2.6 3.9 6.7

Mastocarpas papi_ 2.8 4.8 0.6 1.0 i

lridaea splendens 2.2 3.9 - I

Ralfsia _). 1.7 1.7 0.6 1.0

R_g_sum _ 1.7 1.7 0.6 1.0

CoraUina vancouveriensis 1.1 1.0 1.1 1.0 •

Pelvetia-Pelvetiopsis sp(p). 1.1 1.9 -

Crus_se cor_, nni_. 0.6 1.0 4.4 7.7

Polysiphonia hendryi 0.6 1.0 - •

Petroceli$ sp(p). - 0.6 1.0 II

Total Macrophyte Cover 80.2 52.3 •

Macreinvertebrates - Covet (Percent)

Mytilus califomianus 12.2 11.3 I7.8 21.1 i

Nuttallina californica 2.8 3.5 I. 1 1.9 II

Ba/anus g/andu_ 2.2 1.9 0.6 1.0

Pollicipespolymerus 1.7 1.7 0.6 1.0 •

"Co///se//a" scabra 1.1 1.0 1.1 1.9 1

Tetraclita rubescens 1.1 1.9 1.1 1.9

Ochama_ sp(p). 0.6 1.0 I

dig_ 0.6 1.0 1.1 1.0 1

L/ttor/na scutu/ata/p/ena - 1.1 1.9

I

Lottia paradigitalis - 1.1 1.0

_a _ - 0.6 1.0 •

Phragmatopoma cal_ornica - 0.6 1.0

Total Macroinvenebrate Cover 22.3 26.8 •

Macroinvettebrates- Density(No./0.1875m2)

Lot_ sp(p). 125.0 146.4 108.3 68.8 i

"Co///se//a" scabra 23.3 11.2 25.6 22.0 g

Linorina scundata/plena 19.0 27.1 24.7 42.7

Lottia digitalis 17.9 4.9 21.3 25.2 I!

66 |
I Table 16. Macrophyte, macroinvertebrate, and substratmn abundances in the Myt//us assemblage

cleared plots at Point Sierra Nevada during fall 1992 _(continued).

I Taxon/Substratmn MSpring-Cl ean S.D. eare2d Fall-Clear Mean S.D. ed

I Macroinvertebrates - Density (No./0.1875 m2)

Louiapella 16.0 14.7 39.6 19.1

I LNutt ottia paradigitalis 10.8 3.9 14.3 12.9 aUinacalifornica 9.0 7.0 9.3 9.1

L/ttorbu_keenae 4.0 6.1

I Nucella Strongylocentrotus emarginmapurpuratus 0.3 0.6 00..33 00.6.6

Total Number of Macrophyte Tan 15 11

I Total Nmber of Macroinvertebrate Taxa 14 14

I Total Number of All Taxa 29 25

Substrata - Cover (Percent)

I Bare Rock 18.3 7.3 30.6 t6.7

Rock 2.8 1.0 1.1 1.9

Shell debris I. I 1.0

!

L Dttaaremeamofflh-eepiots(nffi3). Ttxatnd $ubstntta within each categoD" are nmkedacco_ling tothe meaminthe_-

i cleared plots, then listed alphabetically ff the means are equal. Total percent cover can exceed 100 percent because multiple layers were

sampled. A dash (-) indicates the laxoWsubsalmm was not reconkd in the l_Ots indicated.

z S.D. = Standard Deviation.

|

!

67

!
I

1

present in the spring-cleared (and fall-cleared) plots. The larger mussels measured roughly 6 cm 1

or more in length, which was approximately the mean mussel size estimated for the control

mm

plots. These mussels probably encroached into the plot from the surrounding, undisturbed 1

mussel beds. None of the aggregations extended more than about 25 cm (the width of the 1

unsampled border) into a plot and, thus, had not been sampled as of fall 1992.

The smaller mussels (measuring approximately 2-3 em in length) were distributed throughout the i

plots in isolated clumps where they had apparently settled as larvae. It was noted that these

aggregations occupied the lowest spots within a plot. 1

ll

The most abundant macroorganisms in the plots were coralline algae, which accounted for nearly

one-third of the total substratum cover (Table 16). Most of this was due to a single taxon, the 1

articulated coralline alga BossielIa plumosa (30 percent). The tufted green alga Cladophora

columbiana was the second most abundant taxon (19 percent). Bare rock accounted for 18

percent. Two maerophyte taxa, the membranous green algae Ulva sp(p). (6 percent) and the kelp 1

Egregia menziesii (5 percent), were the next most abundant macroorganisms. 1

A number of brown and red algal taxa were observed in the spring-cleared plots in fall 1992 in 1

addition to those discussed above. These taxa together accounted for 19 percent of the total m

substratum cover and included the branched brown alga Analipusjaponicus (3 percent), the

crustose brown algae Cylindrocarpus rugosus (3 percent) and Ralfsia sp(p). (2 percent), the 1

tufted red alga Endocladia muricata (3 percent), and the fleshy red algae Mastocarpus papiUatus

ll

(3 percent), Rhodoglossum aJFme(2 percent), and lridaea splendens (2 percent). The rockweeds m

Pelvetia-Pelvetiopsis sp(p), and the filamentous red alga Polysiphonia hendryi were also 1

observed. Taken together, barnacles (Balanus glandula, Chthamalus sp(p)., Pollicipes

polymerus, and Tetraclita rubescens) composed 5 percent of the total substratum cover. Rock 1

accounted for 3 percent. I

As in the Mytilus control plots, limpets were quite abundant (Table 16). Small Lotaa sp(p), were •

by far the most abundant, with an observed density of 125 per 0.1875 me. Identified limpet taxa 1

included "CoIliseUa" scabra (23), Lott/a digitalis (18), Lottia pelta (16), and Lottia paradigitaIis

(11). The littorine snails L/trot/ha scutulata/plena (19) and Littorina keenae (4) and the chiton •

NuttaUina californica (9) were the next most abundant macroinvertebrate taxa. Total grazer

density included 193 limpets, 23 littorine mails, and 9 chitons.

1

Although species richness observed in the spring-cleared plots on fall surveys peaked in 1992 1

with 29 taxa (Table A-25), there has been substantial year-to-year variation since 1985 (with a

range of 19-29 taxa) and no clear patterns in the numbers of either macrophyte or 1

macroinvertebrate taxa have emerged. The total taxa observed during the most recent survey, in

1

spring 1991, also fell within this range (24) (Table A-26). Overall, 43 different taxa, including

22 maeroinvertebrates and 21 macrophytes, were identified during fall surveys. 1

1

1

68

1
I The results of the fall 1992 survey indicated that mussel abundance (recorded as percent cover) in the spring-cleared plots had increased in comparison with the previous fall surveys (range 0-8

percent) (Table A-25) and the spring 1991 survey (4 percent) (Table A-26), although it was still

I very comparison to plots. Mytilus was most

low in the control the abundant macroinvertebrate

taxon in the spring-cleared plots in both fall 1989 and fall 1992 (but not in spring 1991). Total

i macroinvertebrate cover fluctuated between 8 and 24 percent over the entire survey period.

Although macrophyte abundances in the plots have fluctuated, few clear patterns in abundance

i wpercent), ere discern which abletend . Cetortainhavetaxaa,patchy such asdistribu the tufte tion,d gree appeared n algatoClado varyphora in abundance columbiana throughout (6-19 the

study. However, this apparent variation, may have been due to the sampling method, since the

Bossiella same quadrats plumosawerehasnotremained sampled higeachh relative samplingto peri otherod.macrophyte Cover of thetaxaarti(20-30 culatedpercent) corallinesince algafall

1987. Only one maeroinvertebrate, the limpet Lott/a digitalis, apparently has declined

I subs fall 1989 tantialand ly ifnallabu1992 ndance (from: the97dtoens18ity/0.1875 of this m2). taxon dropped by more than 80 percent between

I The mean recovery rate for the MytiIus assemblage in the spring-cleared plots remained very low,

but reached 0.60 percent per month in fall 1992 (Table 7), a slight increase over the 0.43 percent

per month observed as of spring 1991 (Table A-5). Mussel density in the sampled plots

I (107/0.1875 m2)was substantially higher than in spring 1991 (62). Based on the Bray-Curtis

index (Figure 8), similarity of the MytiIus assemblage in the spring-cleared plots to the control

plots at Point Sierra Nevada also is increasing. The cleared plots can now be considered to be 55

I recovered However, the increased between the control percent (Table 4). similarity Mytilus plots

and spring-cleared plots was probably due at least partially to the recent decline observed in

mussel abundance in the control plots (discussed above), and recovery of the assemblage is

I probably still years away.

i Fall.Cleared Plots

Overall, 11 macrophyte taxa and 14 maeroinvertebrate taxa were observed at Point Sierra Nevada

I incleafall red1pl 992ots, , fortotal a smaero peciesphrichness yte cover(total in thtaxa e f)all-cle of 25ar(Tedabplelots16). in fal Asl w1992 as the(52case percfenort)thewasspringsubstantially greater than total macroinvertebrate cover (27 percent).

I The most abundant maeroorganisms in the fall-cleared plots were mussels (18 percent) (Table

16). The two mussel size classes described above for the spring-cleared plots were also observed

I in the fall-cleared plots. No other macroinvertebrate taxon accounted for more than 1 percent of cover.

I Bare rock accounted for a large part of the total substratum in the fall-cleared plots (31 percent).

Next in order of abundance were several macrophyte taxa: the articulated coralline alga BossieUa

i plumosa (16 percent), the crustose brown alga Cylindrocarpus rugosus (14 percent), the tufted

I 69

I
!

m

green alga Cladophora coIumbiana (9 percent), unidentified crustose corallines (4 percent), and !1

the tufted red alga EndocIadia muricata (4 percent).

U

In addition to the macrophytes discussed above, five brown and red algal taxa were observed in I

the fall-cleared plots. Together, they accounted for only 4 percent of the total substratum cover.

They included the branched brown alga Analipusjaponicus, the articulated coralline alga •

Corallina vancouveriensis, the crustose red algae PetroceIis sp(p)., the crustose brown algae 1

Ralfsia sp(p)., and the fleshy red alga Rhodoglossum aft-me.

As in the spring-cleared plots, observed densities of limpets were quite high (Table 16). Small I

Lott/a sp(p), were again the most abundant taxon (108/0.1875 m2); identified limpet taxa

included Lott/a pelta (40), "ColliseUa" scabra (26), Lottia digitalis (21), and Lottia paradigitalis III

(t4). Densities of the littorine snails Littorina scutulata/pIena (25) and the chiton NuttaUina

californica (9) were close to those observed in spring-cleared plots. Total grazer density

included 209 limpets, 25 littorine snails, and 9 chitons. !

Species richness in the fall-cleared plots has fluctuated over the course of the study (Table A-27).

The total of 25 taxa observed in fall 1992 was within the range observed for the fall 1986 to fall 1

1989 sampling periods (20-33), but was higher than the 19 taxa observed in the spring 1991 m

sampling period (Table A-26). In total, 44 different taxa, including 22 macroinvertebrates and 22 1

macrophytes, were identified in the fall-cleared plots during fall surveys. I

Comparison of all the fall surveys conducted from 1986 through 1992 and the spring 1991 survey

indicated that mussel abundance (in terms of percent cover) in the fall-cleared plots was II

increasing steadily (range 0-18 percent) (Table A-27; Table A-26); mussel abundance in fall

1992 was roughly two-thirds of that observed in the control plots (62 percent) (Table 15). The II

spring 1991 sampling period was the first in which mussels were the most abundant I

macroinvertebrates, as well as the most abundant macroorganisms overall. Total

macroinvertebrate cover increased from less than 1 percent to 27 percent over all sampling III

periods (Table A-27). II

Macrophyte abundances fluctuated over the 7-year sampling period (Table A-27). Although total •

macrophyte cover decreased after reaching a peak in 1987 (from 149 down to 52 percent), no II

substantial changes were observed in fall 1992. The articulated coralline alga Bossiella plumosa,

although the predominant maerophyte at 16 percent of substratum cover, seems to have been [1

declining steadily in abundance since fall 1987 (when it accounted for 58 percent) as mussel II

abundance increased. Limpet densities have also fluctuated (between 82 and 351/0.1875 m2)

overall without demonstrating a clear pattern, i

The mean recovery rate for the Mytilus assemblage in the fall-cleared plots remained very low,

but reached 0.77 percent per month in 1992 (Table 7), a small increase over the 0.47 percent per I

month observed in spring 1991 (Table A-5) and slightly higher than the 0.60 percent per month m

observed in the spring-cleared plots in 1992. Mussel density in the sampled plots in fall 1992 |

70

!
I (I77/0.1875 m2) represented a more than twofold increase over the density observed in spring 1991 (74). As shown in Figure 8, which depicts MytiIus assemblage recovery in terms of the

Bray-Curtis index of similarity, recovery of the Mytilus assemblage in the fall-cleared plots at

I Point Sierra Nevada was continuing and appeared to be occurring somewhat more rapidly than in

the spring-cleared plots. The fall-cleared plots can be considered to be about 67 percent

recovered (Table 4). !

However, as discussed for the spring-cleared plots, the increased similarity between the Mytilus

i con observed trol plointsmussel and fall-c abundance leared pl

inotsthewascontrol probablplots. y dueAsat discussed least partialabove, ly to thit eisrece suspected nt declinthat e this

decrease may be at least partly due to predation by the seastar, Pisaster ochraceus.

!

2. Endocladia/Mastocarpus Assemblage

I As throughout discussedthebestudy, low, thwith e Endbare ocladrockia/Mastocarpus accounting forconroughly trol plo50ts percent have remain of totedalrelati area.veTlotal y barren

macrophyte cover has fluctuated between about 60 and 35 percent.

I In fall 1992, species richness was low in the EndocIadia/Mastocarpus control sites; only eight

taxa (2 macrophytes and 6 macroinvertebrates) were identified (Table 17). Total macrophyte

cover was quite low in fall 1992 (35 percent), and total maeroinvertebrate cover was even lower

I (percent). 16

Bate rock accounted for 52 percent, or more than one-half of the unoccupied area, in the control

I plots in fall 1992, and rock composed another 18 percent (Table 17). In general, the plots

appeared to be extremely desiccated. The tufted red alga Endocladia muricata predominated,

i comaeroinv vering eone- rtebrat thirde tax (32a,ptherecebnarnacl t) of these Chthamalus substratum asrep(a.p).N(e8xtpercin eabun nt) andadncethewlitt ereorintweo snails

l.,ittorina scutulata/plena (6 percent). The fleshy red alga Mastocarpus papillatus contributed

i • only 3 percent to total cover. Endoclad/a and Mastocarpus were the Onlymacrophyte taxa

observed in the control plots in fall 1992.

I Thmaeroinv e liRorine snails L/ttorina scutulata/plena were by far the most abundant motile ertebrate taxa in the control plots, with an observed density of 683 per 0.1875 m2.

L/ttor/na keenae also occurred, but at a much lower density (2). The snail TeguIafunebralis and

I one limpet taxon, Lottia paradigitalis, were the only other macroinvertebrate taxa observed. Total grazer density included 685 littorine snails and 1 Tegula snail.

!

71

'!

!
m

Table 17. Macrophyte, macroinvertebrate, and substratum abundances in •

the Endocladia/Mastocarpus assemblage control plots at Point

II

Sierra Nevada during fall 1992.1

Standard m

Taxon/substratum Mean Deviation

II

Macrophytes - Cover (Percent) m

Endocladia muricata 32.2 26.9 1

Mastocarpus pcqTillatus 2.8 4.8

Total Macrophyte Cover 35.0 l

m

Maeroinvertebratcs - Cover (Percent)

Chthama/us sp(p). 7.8 13.5 I

L/ttor/na scutu/ata/p/ena 6.1 4.8 I

Littorina keenae 1.1 1.9

Pagurus sp(p). 0.6 1.0 I

I

Total Macroinvertebr_ Cover 15.6

Macreiavertebrates - Demtty (No./0.1875 m2) I

m

L/ttor/na scutu/ata/p/ena 683.4 504.1 n

L£qor/na keenae 2.0 2.7 •

Tegulafunebralis 1.3 2.3 m

/att/a parad/g/ta//s 0.3 0.6

I

Total Number of blacrophyte Tan 2 m

Total Number of Macroinvertebrate Ttum 6 1

Total Number of All Taxa 8

Subarata - Cover (Percent) m

Bare rock 51.7 25.0

Rock 18.3 16.1 I

t Dalaareme_ofthgeept_s(n=3). Taxatndmbstnttawithineachcalegorya_ ranked

e,cconfling ,xceedI00mpd_en:m_mebe.amcaus llz, _temul _ _ alldmb layersewdmere_mmpl ify them_._au_m _pml. Tc_mlper_*mcovercan 1

I

72 m
I There was relatively little change in the species richness observed at this site during fall surveys

from 1985 through 1992; totals fluctuated between 5 and 12 taxa, with greatest variation being

I observed in the numbers of macroinvertebrate taxa (range 2-9) (Table A-28). The total observed

in spring 1991 was slightly higher (13) (Table A-29). Overall, 21 different taxa, including 14

macroinvertebrates and 7 macrophytes, were identified during fall surveys. !

Comparison of the results of the fall surveys conducted from 1985 through 1992 (Table A-28)

and of the spring 199I survey (Table A-29) yielded few clear patterns, either in the percent of the

substratum covered by various taxa or in macroinvertebrate densities. Total macroinvertebrate

cover fluctuated between 6 and 16 percent during the overall sampling period. Although total

i macrophyt at any of thee cov siteesr (from at Point66Sidowerran Ntoevada 35 perecxhibit ent), ema d ctherophyte greatestcovdrop er atfromthis site 1985actually to 1992appears observedto

have fluctuated annually between about 60 and 35 percent. The tufted red alga Endocladia

I mcovuricereatad bhas y thispretaxo domin n has atedreminathinede cobnetrolowl plo50tsperthrceountghsinoucet ththee sfitudrsty,survbuteytointalfail subs1985 tratum(range 23-

48 percent). Abundance of the fleshy red alga Mastocarpus papillatus appears to have fluctuated

I in approximately 2-year cycles, with peaks at 15-18 percent of substratum cover and lows at 2-3 percent.

I The density of the littorine snails Littorina scutulata/plena and Littorina keenae observed in fall 1992 (685/0.1875 m 2) was approximately twice that of fall 1989 (348) (Table A-28) and spring

I99I (320) (Table A-29). At Point Sierra Nevada, littorine snail densities in the control plots

I have fluctuated greatly over time on an apparently seasonal basis, with highest densities generally being observed during the fall. The barnacles Chthamalus sp(p), appear to have grown or

colonized the plots: the area covered rose from less than 1 percent to 8 percent between fall 1989

I and fall 1992.

As shown in Figure 9, which depicts Endocladia/Mastocarpus assemblage plot recovery in terms

I of the Bray-Curtis index of similarity, the degree of similarity among the control plots in 1992

remained within the range observed during previous years, but them has been a trend toward

i decreasing depauperatesimilarity condition amo of nsomg the eofplothese ts sincplots e 1988. duringThirecent s mayyear besrel . ated to the somewhat

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I IV. DISCUSSION

A. Comparison of the Mytilus Assemblage at the Four Study Sites !

I The Mytilus californianus assemblage is known to take considerable time to recover following

disturbance to areas that are generally larger than 0.01 m2(e.g., Hewatt, 1935; Castenholz, 1967;

i Cimbe 1992 show rg, 19that 75;aft Painer e71⁄2andyeLev ars,innon, 1981 e of;thKine MytiIus netic Laass boeratmblag oriese, Inplots c., 1tha99t2).wereTheclereared sultsbyfrom fall

Kinnetic Laboratories, Inc. (1992) have shown complete recovery (see discussion under SpringI and similarity Fall-Clea between red Plclea ots, rbelo ed and w). control This wpas based on a comparison of the Bray-Curtis index of lots at each of the four study sites (Figures 2, 4, 6, and 8).

Since the last assessment of these plots by Kiunetic Laboratories, Inc. (1992), in the spring of

I was 1991, there has been a gradual increase in recovery (similarity) at all sites. However, the increase • small and it occurred very slowly (Table 7). The spring-cleared plots have recovered from

39 percent at Kibesillah Hill to 68 percent at Pescadero Rocks (Table 4). The fall-cleared plots

I have recovered from 34 percent at Sea Ranch to 67 percent at Point Sierra Nevada.

£anttaI.P_lo

I Mussels typically cover vast expanses of rocky intertidal features in central and northern

California, although the distribution at a particular site may be patchy (Ricketts et al., 1985). The

I Mytilus assemblage to extremely (Kanter, 980) is multilayered

is known be rich 1 and often

(Kanter, 1976, 1980; Straughan and Kanter, 1978). The results from the fall 1992 study showed

i thMyat the mussel Mytilus californianus was by far the most abundant (percent cover) taxon in the tilus control plots at all study sites (Table 18). MytiIus covered almost all (99 percent) of the

available rocky surface at Kibesillah Hill, the northernmost site, while at Point Sierra Nevada, the

i southernmost site, it covered only 62 percent of the substratum.

The Mytilus assemblage at KibesiUah Hill was characterized by large, densely aggregated, and

I mul multilayered tilayered musse assemblage ls withexhnumibited erousthemacroin highestvertottebalrate biotic s andcover macro (153phyt peerscent) attacofhedalltothethsites em. This

(Table 19). At the other sites, multilayering existed, but to a lesser degree. The mussels were

I smto Kibesill aller anahd less Hill:densel Pescay dagerogreRoc gatedks,

(132 and tpeotr

acent) l bio,ticSeacover Ranwas ch (12so9mepercent) what re,duandcedPoint in comSieprararison

Nevada (113 percent). The vast majority of the total biotic cover at all sites was from

I macroinvertebrates (range 78 - 130 percent).

The MytiIus assemblage at Point Sierra Nevada supported the greatest species richness of all the

i sites, with a total of 31 taxa observed during the fall 1992 sampling period (Table 19).

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Table 18. "l'ne more abundant (> 2 percent cover) taxa in the Mytilus assemblage control plots at the four •

study sites during fall 1992. _

II

Kibesmab Sea Pescadero Point Sierra •

Taxon Hill Ranch Rocks Nevada II

My:ilus califmnianus 98.9 93.3 80.6 62.2 •

Chthama/as sp(p). 13.3 8.9 4.4 <2.0

lid

Endocladia muricata 12.2 5.6 < 2.0

Anthopleura eleganrissima 10.6 - < 2.0 m

Mastocarpus papiUams 10.6

Ba/anus g/andu/a 5.0 8.9 16.7 3.3

Pollicipes polymerus - 6.1 6.1 6.1 •

Tetraclita rubescens - 16.1 <2.0 |

GATGOR - 2.8 < 2.0

Bossiella plumosa - - 11.7 I

CoraUina vancouveriensis - - 10.0 •

Crustose corallines, unid. - < 2.0 6.1 J

Dataaremeansof threeplots(n ,= 3). Taxaarerankedaccordingtonueamsat KibesiUthHiII, thenlistedtlphabeficallyifthe meansare I

equalatthatsite. A dash(-)hxlk.ateths e taxonwas nntrecordedatI1_ site.

I

Table 19. Species richness, biotic cover, and sulmtratum abundance in the MytUus assemblage control plots

at the four study sites during fall 1992) 1

I

Kibesmab Sea Pescadero Point Sierra

Category Hill Ranch Rocks Nevada 1

Species Richnem (No. of Tan)

Total No. of Macrophyt_ 2 3 4 10 II

Total No. of Macroinvertebrates 12 11 13 21

Total No. of Taxa 14 14 17 31 1

U

Cover (Perceat)

Total Macrophyte Cover 22.8 7.9 5.7 34.7 !

Total Macroinvertebrate Cover I30.1 121.1 126.1 78.0

Total Biotic Cover 152.9 129.0 131.8 112.7

Bare Rock <2.0 6.1 n

Rock < 2.0 3.3 2.2

Shell Debris 1.7 <2.0 - 1.7

! n Cover data for biota and mbstramm ate means of three plots (n _= 3). Tend percent cover can exceed 100 percent because multiple layers

were sampled. A duh (-) iadicates the sub_ramm was not recmded at that site.

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I Macroinvertebrates contributed 21 taxa and macrophytes contributed 10 taxa to this total.

Species richness at the other sites was about one-half of that measured at Point Sierra Nevada,

ranging from 14 to 17 taxa. The total number of macrophyte taxa (2 to 4) at these sites was less

I than half of that measured Point Sierra Nevada. The total number of macroinvertebrate

at taxa at

these sites (11 to 13 taxa) was just over half that measured at Point Sierra Nevada.

I The higher species richness (Table 19) at Point Sierra Nevada may be attributed to the low

abundance of MytiIus--only 62 percent of the substratum was covered by mussels (Table 18).

i Thoccupied e absence by other of mussel taxas(sineeoPai vernone e, 1974). -third oItf thiselikely plot wthat ouldtheprplots ovidehave morebeavenaildisturbed able areaattosome be

point by predation by the seastar Pisaster, crabs, or shorebirds, by storm and/or wave-related

I dama successional ge, or bystage human effects (harvesting, trampling), and they appeared to be at an earlier than the control plots at other sites. Although the plots at the other study sites

may have been subject to similar disturbances, mussel cover remained high (range 81 to 99

I percent).

In contrast to macroinvertebrates, maerophytes were not as abundant in the mussel dominated

I assemblage (Table 19). Total maerophyte abundance was greatest (35 percent cover) at the site with the highest species diversity, Point Sierra Nevada, where macrophytes were attached to both

the mussels, and the relatively abundant primary substratum. The next greatest total macrophyte

I cover (23 pereen0 was at the KibesiUah Hill site, where macrophytes were often observed attached to mussels. Macrophyte cover was much lower at Sea Ranch (8 percent) and Pescadero

Recks (6 percent). !

Other than Mytil_, the barnacle Balo_s glarMula was the only maeminvertebrate that had cover

greater than 2 percent at all of the sites (Table 18). Two other ba_acle taxa were abundant at

I three of the four sites: Chthamalus sp(p)., with greater than 4 percent cover at all sites except

Point Sierra Nevada; and PoUicipes polymerus, with 6 percent cover at all sites except Point

i Sierra Nevada.

At Point Sierra Nevada, where Mytilus abundance was the lowest of all the sites (62 percent

I cCorallin over), coe ralli alganee incalgluadee dcothveereadrtiacubolat uted28cor pearcen llinet ofalgae the suBossiella bstratumplumosa in the MytiIus (12 perceasnset)mblage. and

Corallina vancouveriensis (10 percent) and erustose corallines (6 percent) (Table 18). None of

I these coralline algae were common (>2 percent cover) at any of the other sites. Although coralline algae were an important feature at Pescadero Recks in earlier surveys, they steadily

declined in cover as mussel cover increased (Table A-16).

I Although the barnacle Tetraclita rubescens (17 percent cover) and the green algae GATGOR (3

percent) were among the more abundant sessile macroorganisms at Pescadero Rocks, they were

I not sampled at other site, except Point Sierra Nevada, where both taxa were present at

any

minimal levels (<2 percent cover) (Table 18). Similarly, cover of the fleshy red alga

i Mastocarpus papillatus and the sea anemone Anthopleura elegantissima both were fairly high

77

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(11 percent) at the Kibesillah Hill site, but Mastocarpus was absent at the remaining sites, and II

Anthopleura was sampled at a very low level (<2 percent cover) at one other site (Point Sierra

Nevada). Cover of the tufted red alga Endocladia muricata was also fairly high at Kibesillah

Hill (12 percent), with reduced cover at Sea Ranch (6 percent) and Pescadero Rocks (less than 2 I

percent). This alga was not observed in the Mytilus control plots at Point Sierra Nevada. u

Limpets, the snail TeguIa funebralis, and littorine snails were the only common (greater than 1

3/0.1875 m2)grazers at the four study sites (Table 20). However, the abundances showed

U

marked differences at each site. Limpets were the most abundant grazer at three sites, although I

their density varied greatly among sites. Sea Ranch had the greatest limpet density (209), 1

followed by Point Sierra Nevada (103), and Peseadero Rocks (67). The snail Tegula was

abundant at Kibesillah Hill (28), but the only other observation of that taxon was at Point Sierra n

Nevada, where density was less than 3. Littorine snail density was higher at Kibesillah Hill (21) |

and Pescadero Rocks (19), than at Point Sierra Nevada (6) and Sea Ranch (less than 3).

I

MII

study

sites during fall 1992) I

Klbesillah Sea Pe:_eadero Point Sierra

Taxon Hill Ranch Rocks Nevada I

Tegulafunebralis 28.3 - <3.0 I

N

Littorine snails 21A <3.0 19.1 6.1

I

Limpets 20.9 209.2 67.2 102.9

_Da_aarememsoftlaeeplots(n= 3). Gm_1_ermked _g to themeansat _HiU. A I

dash(-)indicatesthe grazerwasnotw.zerdedst thatsite.

I

Predatory snails were uncommon at the study sites, and only two taxa were observed: Nucella

emarginata, with less than 3/0.1875 m 2 at Kibesillah Hill (Table 5) and less than 1 at Point Sierra [1

Nevada (Table 15); and Ocenebra circumtexta, with less than 1 at Point Sierra Nevada (Table I

15). Due to the structural complexity of the MytiIus assemblage, the sampling methodology most

likely underestimated these small gastropods and other macroinvertebrates that were situated n

beneath and among the mussels. Indeed, Kanter (1980) took 1500-era 2 cores (five 300-era 2

I

replicates) of mussel beds in the Southern California Bight and found that the mussel beds at Cat m

Rock on the south side of Anaeapa Island supported 174 species of invertebrates and 15 algal I

species. A total of 610 faunal species and 141 species of algae were quantified from mussel beds

at 20 study sites, n

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I There have been several noticeable differences in the Mytilus assemblage among the study sites since the study began in 1985. For example, Mytilus cover at Kibesillah Hill (Table A-1) and

Sea Ranch (Table A-9) has shown comparatively little variation in abundance since 1985. While

I mussel cover generally remained the same at these two sites, there were changes in the abundances of some of the other taxa. In particular, at Kibesillah Hill (Table A-I) two

macrophyte taxa (the tufted alga Endocladia muricata and the fleshy red alga Mastocarpus

I papillatus) two taxa (the sp(p), sea

and macroinvertebrate barnacles Chthamalus and the

anemone Anthopleura elegantissima) increased in abundance. In contrast, at Pescadero Rocks

i Nevada (Table A-1(Tabl 6) ethere A-23)hasthere beenhasa subeen bstantial a temporary increaseincrease of Mytilusin mussel since 19cover 85, while in 1988at Point and aSdecline ierra

in 1992. Other changes in the Mytilus assemblage appeared to be related to either increases or

i dPescadero ecreases inRocks Mytilus(Table abunA-16), dance there at thewas studya corresponding sites. For examdecrease ple, whenin macrophyte ussel coverabundance increased inat

the plots. Similarly, at Point Sierra Nevada (Table A-23), as mussel cover decreased, coralline

I algae increased, whereas barnacles and limpet grazers decreased

Spatial variation among sites has been previously found in other mussel assemblages. Dayton

I (19 Washingt 71) found that the high degree of spatial variation in the barnacle/mussel assemblage on the on coast was due to continuous physical and biological disturbance preventing

complete monopolization of space by one species. The disturbances he identified were grazing

I by limpets, predation by carnivorous gastropods and seastars, and battering by waves and logs. Paine and Levin (1981) have proposed a model that describes the composition of mussel

communities of the outer coast of Washington as a mosaic of patches of various ages and sizes in

I various stages of recovery.

The results of this study suggest that Mytilus competes with macrophytes (especially corallines)

I for substratum and substratum for barnacles and

primary provides _ondal'y some macrophytes

(see also Kinnetic Laboratories, Inc., 1992). However, there have also been suggestions (Bayne,

1976; Suehanek, 1979) that Mytilus preferentially recruits into eoralline and other filamentous

I species, indicating a possible facilitation relationship (sensu Connell and Slatyer, 1977).

i AthecoBray-C mparisourti n sofindex the Mytilus of similarity control(Figures plots at2,ea4,ch6,ofandthe 8)fouindicates r study sthat ites froin mfall1I992 985-1the 992Mytilus using

assemblage control plots were about as similar to one another as they had been in most previous

I surveys.

Spring-Cleared Plots

I In fall 1992, the highest species richness (total number of taxa) in the spring-cleared Mytilus

plots at the four study sites was at Kibesillah Hill (34 taxa) (Table 21). This total included 16

I macrophytes and 18 macroinvertebrates. The total number of taxa at the three other sites was only slightly less (range 28 to 32). Kibesillah Hill also supported the greatest total biotic cover

(I 34 pereen0. The vast majority of the total cover at this site was contributed by macrophyte

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Table 21. Species richness, biotic cover, and substratum abundance in the Mytilus assemblage spring- •

cleared plots at the four study sites during fall 1992__

Kibesillah Sea Pescadero PointSierra •

Category Hill Ranch Rocks Nevada |

I

Species Richness (No. of Tan) i

Total No. of Macrophy_s 16 15 12 15

Total No. of Maeroinvertebrate 18 17 16 14 •

l

Total No. of Taxa 34 32 28 29

Cover (Percent)

Total Macrophyte Cover 100.0 31.9 58.5 80.2 I

Total Macroinvertebrate Cover 33.5 63.0 64.5 22.3

Total Biotic Cover 133.5 94.9 123.0 102.5 •

Bare Rock 7.2 19.4 2.8 18.3 I

Rock 29.4 6.1 6.1 2.8

Shell Debris - 1.7 1.1 n

s..0 06 l

Cover data for bimaand mflmamum are meam of three plots (n= 3). Total pmmm cover can exceed 1O0 percent became multiple layers were

sampled.A dash(-)indicatesthembstratumwasnotmtxad_ atthatsite. I

taxa (100 percent). In contrast, at Pescadero Rocks and Sea Ranch more cover was from

macroinvertebrates (63 percent, primarily mussels and barnacles) than from macrophytes (32

percent). Macroinvertebrate cover was two to three times higher at Pescadero Rocks (65 percent) •

and Sea Ranch (63 percent) than at Kibesillah Hill (34 percent) and Point SierraNevada (22 I

percent). Bate rock was notably higher at Sea Ranch (19 percent) and Point Sierra Nevada (18

percent) than at Kibesillah Hill (7 percent) or Pescadero Rocks (6 percent), nI

The results from fall 1992 showed that after 7Vz years none of the Mytilus assemblage plots that

were cleared in spring 1985 by KLI have shown complete recovery. Four measures of the •

Mytilus assemblage were used to determine recovery. The most important was a comparison of I1

the similarity of the cleared plots to the control plots. Mussel cover, mussel density, and

recovery rates were also assessed. Each of these measures are discussed below, n

A comparison of Bray-Curtis index of similarity between the spring-cleared plots and the control

plots at each individual site showed thatrecovery was proceeding (Figures 2, 4, 6, and 8). Since n

the last assessment of these plots by Kinnetic Laboratories, Inc. (1992) in the spring of 1991,

m

there has been a small, gradual increase in recovery (similarity) at all sites. The spring-cleared 1

plots at Point Sierra Nevada and Pescadero Rocks appear to be closer to recovery than the two n

northernmost sites. The percent recovery of spring-cleared plots ranged from a low of 39 percent

U

at Kibesillah Hill to a high of 68 percent at Pescadero Rocks (Table 4). 1

U

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I
I Abundance (percent cover) of Mytilus in the spring-cleared plots slowly increased at all sites

between the spring 1991 assessment by Kinnetic Laboratories, Inc. (1992) and the fall 1992 study

(Table 22). In spring 1991, KLI found Mytilus cover to be below 25 percent at all sites except

I Pescadero Rocks, where it covered 30 percent of the substratum. By fall 1992, mussel

abundance exceeded 25 percent at two sites, and Pescadero Rocks continued to have the greatest

abundance of Mytilus (36 percent cover). Between spring 1991 and fall 1992, the greatest

I increase in occurred Point Sierra where mussel to 12 Mytilus at Nevada, cover

tripled (4 percent

percent).

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Table 22. My_ cover (percent) m spring- mid fal|-el_r_l plots at the four study sites du_ sp_g 1991

I andfall

Spring1991" Fall1992

I Site Spring-Cleared Fall.Cleared Spring-Cleared Fall-Cleared

i KibesillahHill 18.3 16.7 21.1 19.4 SeaRanch 21.7 6.1 27.8 8.9

I PescaderRo ocks 30.0 10.6 36.1 17.8

PointSierraNevada 4.4 6.7 12.2 17.8

I t Data artmeansof threeplotsin = 3)"

2Slating1991data me fromKianeticl.,abctatm_, inc. (1992).

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I Tperhespedectnsity of Myrilus (noJ0.1875 m2) in the spring-cleared plots (Table 23) provided a different ive on abundance than did the cover data. Mussel density declined by two-thirds

between spring 1991 and fall 1992 at Kibesillah Hill (121 to 39). In contrast, mussel density at

I the three more southern sites increased by one-third to three-fourths during the same period, with the greatest increase occurring at Point Sierra Nevada (62 to 107). These differences may be due

to variability among quadrats within aplot, since the same three quadrats were not sampled

I dmurussel ing each sampling period, or due to differential colonization rates or encroachment by s.

I The rates observed in fall 1992 (Table 24) were all low compared to the recovery very recovery

ratesfor the Endoc/ad/a recovery study conducted by KLI. In thatstudy (Kiunetic Laboratories,

Inc., 1992; Table I-I), recovery rates ranged from 2.2 to 10.3 percent per month. The recovery

I rate estimated for the Mytilus assemblage at Pescadero Rocks in fall 1992 (0.75 percent/month)

was the highest of all the sites for the spring--cleared plots (Table 24). It was only slightly higher

i than the rate observed at this site in spring 1991 (0.69 percent/month, Table A-5). These plots

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Table 23. Myf/us density (no./0.1875 m2) in spring- and fall-cleared plots at the four study sites during I

spring 1991 and fall 1992:

Sit Spring 19912 Fall 1992 I e Spring-Cleared Fall-Cleared Spring-Cleared Fall-Cleared

Kibesillah Hill 121 63 39 63 I

Sea Ranch 59 13 85 37

Pescadero Rocks 186 55 247 126 I

Point Sierra Nevada 62 74 107 I77 I

' Dataaremeansofthreeplots(n = 3).

2 Spring1991dataavecalculatedbydividingthetotalmusselcountsmKinae_LaboratorieInc. s, (1992)forallthreesprig-clearedorfall- I

c_u_d plotsby three.

I

I

Table 24. Myt//us assemblage recovery rates at the four study sites during spring 1991 ud fail 1992.1

Spring 1991z Fall 1992 I

Site Spring-Cleared Fail-Cleared Spring-Cleared Fall-Cleared

Kibesillah Hill 0.47 0.48 0.43 0.49 I

Sea Ranch 0.82 0.66 0.55 0.41 I

Pescadero Rocks 0.69 0.38 0.75 0.50

Point Sierra Nevada 0.43 0.47 0.60 0.77 I

'Dm a_ meamof _ree plots(n = 3). Recoveryrate(pe_eet/momh)wascalculatedbydivid_ theBray-Curtisndexofsimilarity •

(percent)fora givenc.k_edplotby thepercent_ of theleastsimilarcommlplots,naddply_gby 1_0,anddividingbythemusherof II

monthstothe lastsmnpl_ date.

2 Springt991damaxefromKinneticIAdmmm_s0Inc.0992). •

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I appear to have recovered more (68 percent recovered) than those at the other sites based on the Bray-Curtis index of similarity (Table 4; Figure 6). Additionally, the mean mussel density has

increased by one-third since spring 1991 (Table 23). However, as noted by Kinnetic

I Laboratories, Inc. (1992), the higher rate of recovery in Pescadero Rocks plots in spring 1991

may have been an artifact of comparing these cleared plots to control plots that were at an

intermediate level of succession. This artifact is less likely to be important at Pescadero Rocks

I that the control be in late of succession.

now plots appearto a stage

i Fall-Cleared Plots

The three northernmost sites (Kibesillah Hill, Sea Ranch, and Pescadero Rocks) exhibited

i relati clearedvelyplotssimilar (Tablespec25). ies riPoint chnessSierra (totalNevada numbershadofthetaxlowa) e(3st2,richness, 31, 30, re25specti taxa. vely)Theingreatest the fallnumber of maerophyte taxa (19) was observed at Kibesillah Hill (range for all sites 11 to 19),

I whe to 18). reas the most macroinvertebrate taxa (18) were observed at Sea Ranch (range for all sites 13

I

Table 25. Species riclmess,biotic cover, andsubstratum abundance in the MytUus assemblage fall-cleared

i plots at the four study sites during fall 1992.I Kibesillah Sea Pescadeco Point Sierra

Category Hill Ranch Rocks Nevada

!

Species Richness (No. of Taxa)

I TotalNo. of Maerophytes 19 13 17 11 TotalNo. of Macroinverte. 13 18 13 14

Total No. of Tara 32 31 30 25

I Cover (Percent)

I Total MaerophyteCover 66.0 59.0 85.7 52.3

Total MaeroinvertebrateCover 39.7 29.8 37.4 26.8

TotalBioticCover 105.7 88.8 123.l 79.1

BaxeRock I3.3 24.4 7.2 30.6

I RShocellkDebris 12.2 253..96 2.2 0.6 1.1

I Cover data fm"biota and mhslnemn a_emem_ofthree plots(n= 3). Teca]percentcovefcan exceed I00 percentbecausenafitiplelayerswe_

I

sampled. A dash (-) indkates the mbstrmmnwas notrececd_ at thats/re.

I

I

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In contrast to the spring-cleared plots, where total biotic cover was highest at KJbesillah Hill, •

total biotic cover was highest in the fall-cleared plots at Pescadero Rocks (123 percent).

m

Pescadero Rocks also had the highest macrophyte cover (86 percent). Macroinvertebrate cover n

was highest at Kibesillah Hill (40 percent) and Pescadero Rocks (37 percent). There was a large

amount of bare rock at both Point Sierra Nevada (31 percent cover) and Sea Ranch (24 percent

cover). I

Results from fail 1992 showed that after 7 years none of the Mytilus assemblage plots cleared by

KLI in fall 1985 have shown complete recovery (Figure 2). As indicated above, four measures of •

the Mytilus assemblage were used to determine recovery: comparison of the similarity of the

cleared plots to the control plots, mussel cover, mussel density, and recovery rate. These

measures are discussed below. I

I

A comparison of the Bray-Curtis index of similarity between the fall-cleared plots and control

plots at each of the four sites showed that recovery is proceeding (Table 4; Figures 2, 4, 6, and 8). 1

Since the last assessment of these plots by KLI in the spring of 1991, there has been a gradual

increase in recovery (similarity) at all sites, although the increase has been low. The percent

recovery of the fall-cleared plots ranged from a low of 34 percent at Sea Ranch to a high of 67 1

percent at Point Sierra Nevada (Table 4). The fall-cleared plots at Point Sierra Nevada may have m

been closer to recovery than the three more northern sites, due in part to the slightly lower m

among-control similarity at the Point Sierra Nevada site that resulted from a decline in Mytilus. I

Results from the fall 1992 study showed that mussels continued to increase slowly in abundance n

(percent cover) in the fall-cleared plots at all study sites (Table 22). In spring 1991, MytiIus

covered only 17 percent of the substratum at Kibesillah Hill, 11 percent at Pescadero Rocks, and

between 6 and 7 percent at Sea Ranch and Point Sierra Nevada (Kinnetic Laboratories, Inc., •

1992). By fall 1992, Mytilus occupied about the same amount of substratum (18 to 19 percent) in |

fall-cleared plots at all sites except for Sea Ranch, where it covered only 9 percent. Mussel cover

more than doubled at Point Sierra Nevada between spring 1991 (7 percent) and fall 1992 (18 •

percent). II

Mytilus density data (no J0.1875 m2)from the fall-cleared plots furnished a slightly different view •

of abundance than did the cover data (Table 23). Mussel densities increased about two- to threefold between spring 1991 and fall 1992 at the three southernmost sites, but remained the same

(63) at KibesiUah Hill. Point Sierra Nevada had the highest mussel density (177) in fall 1992, •

whereas the mussel densities at the three more southern sites ranged from 37 to 126.

The mussel recovery rate for fall-cleared plots at Point Sierra Nevada was the highest (0.77

percent/month) for both spring and fall--cleared plots at all the sites (Table 24). This rate is []

higher than the 0.47 percent/month observed for the same Mytilus plots by Kiunetic Laboratories, m

Inc. (1992) in spring 1991. This higher recovery rate (Table 24) may be an artifact of the

unusually low mussel cover in the control plots (62 percent, Table 18). This was the lowest

Ill

Mytilus cover of all the sites in fall 1992, and the control plots themselves were probably in an !
I intermediate stage of succession. Therefore, the cleared plots may become more similar to the

controls more rapidly, as a result of this low mussel cover in the control plots and the fact that

they are in an intermediate stage of succession.

I Complete recovery of the spring- and fail-cleared Mytilus plots at all the sites will probably take

several more years. As Kirmetic Laboratories, Inc. (1992) concluded, the recruitment dynamics

I more abundant species and, possibly, human disturbance contribute to a recovery process

of the

that varies greatly among sites and from year to year. Although it is impossible at this time to

i deplotstermiatnePescadero how longRocks compand lete Proecinove t SiryerrawillNeactuall vada ymaytake,recthoveerressooultnserindicate than atthathet thtweoclmeoarreed

northern sites. This is based on the similarity of the cleared plots to the control plots and on the

i reco and vegrowth ry rateofs.Mytilus Actual inrecothevefuture ry timeand, woul perhaps, d dependuponupofurther n manyencroachment factors, includbyingadults the recruitment living on

the boundaries of the cleared plots.

!

B. Comparison of the Endocladia/Mastocarpus Assemblage at the Four Study Sites

|

I As discussed below, the Endocladia/Mastocarpus assemblages at the study sites have generally remained similar to previous fall sampling periods, although the abundances of macrophytes and

macroinvertebrates have fluctuated since the study began in 1985.

I The Endocladia/Mastocarpus assemblage is a conspicuous and diverse assemblage of biota that

typically occurs on the high rocky intertidal shoreline throughout central and northern California

i (Glynn, 1965; Ricketts et al., 1985). Results from the fall 1992 study showed that the species

richness and total biotic cover within this assemblage differed greatly among all the study sites

(Table 26). The highest species richness (total number of taxa) and total biotic cover, were at

I Sea site. Ranch Togeth. eAr, tothtese al ofbi2o9tatacxove a (rIe7d maatot crophyt al of es139andperc1e2ntmaofcroinv the seurtbstratum. ebrates) was Macrophytes observed at this

contributed 131 percent cover to this total, while macroinvertebrates occupied 8 percent of the

I suandbstr12a7tupm. ercSenptec)ies and riKib chnesessillaand h Hitllotal(24biotatixca cand over103wepereralcesont).highIn atmaPesca rked dcont erorasRocks t, the(2I taxa

EndocladialMastocarpus assemblage at Point SierraNevada supported only eight taxa (2

i macrophytes and 6 macroinvertebrates), and these taxa covered only one-half of the substratum.

The tufted red alga Endocladia muricata and the fleshy red alga Mastocarpus papiUatus, the two

I "indicators" of this assemblage, were the only macrophytes present at all four sites (Table 27). These macrophytes were abundant at Pescadero Rocks (Endocladia - 50 percent; Mastocarpus -

24 pereen0 and Sea Ranch (Endoc/ad/a - 48 percent; Mastocarpus - 21 percent). Endocladia

!

85

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Table 26. Species richness, biotic cover, and substratum abtmdauce in the _Mastocarpus assemblage control •

plots at the four study _tes duringfail 1992._

i

_E_ Sea P_o Point S_-t_ •

Category H_ Ranch Rocks Nevad_ i

Species Ridmess (No. of Tan) n

i

TotalNo. of Macrophytes 12 17 12 2

Total No. of Macminvertebrates 12 12 9 6

Total No. of Tan 24 29 21 8 1

n

n

T_ Ma_ Cover 89.0 130.6 125.1 35.0 i

TotalM_roinv_. Cover 14.0 7.9 2.3 15.6 U

TotalB_c Cover 103.0 138.5 127.4 50.6

Bare Rock 27.2 7.2 10.6 51.7 •

Rock 18.9 32.2 24.4 18.3 i

Shell D_ 1.1 - -

' Coverdamforbiotam_ m_um aremeansof three_ (n = 3). T_ _ cover_m e_ 1_ _ _ m_e I_yers n

were _m_. A _ (-)_ _ m_w_um wasnotn:co_ _ _t _.

n

Ti_ _. _ more _ (>2 _'eemt ¢ever) _um in the F_docladia/Manecarpus assemblage centrol plots at the i

fotw study si_s dm'ing fall L$92.n

i

Kibesillah Sea Pmcadero Point Sierra i

Tax_ HW _ Rocks Nevada i

Fucus gm_u_ 22.2 18.3 - n

EM_m_ _ 17.8 48.3 50.0 32.2

C_wra _ I3.3 17.2 5.0 n

Ma.notw-puspapi/kuus 11.1 21.1 23.9 2.8 •

Petroce//s sp(p). 7.2 5.0 < 2.0

Am_tm _gw_,_ 6.7 < 2.0 -

_). 5.0 < 2.0 - 7.8 1

_ _m_ 5.0 2.2 -

I Cmsto_ _1_, _. 3.9 <2.0 5.0

It/dam sp/endens 3.9 < 2.0 -

Cryptosogan_a woodii - 3.9 - •

Pelvecia-Peh_Iiopsissp(p). <2.0 3.3 21.1 U _ssum _u_ - 10.0

R_ crusts <2.0 3.3

Ul_ sp(p). <2.0 2.8 i

Pisaster ochraceus - 2.2 -

Liuorina scuudma/plena < 2.0 - 6.1

Dataare means of threeplots (n = 3). Taxaare generally rankedaccordingto means at KibesillahHflI, thenlisted 1

alphabeticallyif themea_ are equal. A dash(-) indicatesthe laxtmwas not recordedat thatsite.

!
I cover was comparatively lower in abundance (18 percent) at Kibesillah Hill, and Mastocarpus

cover was comparatively much lower (3 percent) at Point Sierra Nevada.

Other common macrophytes included the tufted alga CIadophora coIumbiana, which was

green

notably abundant at Sea Ranch (17 percent cover), Kibesillah Hill (13 percent cover), and

Pescadero Rocks (5 percent cover) (Table 27). Two rockweed taxa (Fucus gardneri and/or

I Pelvetia/Pelvetiopsis sp(p).) covered a fairly large amount of the substratum within the

Endocladia/Mastocarpus assemblage at three sites: Kibesillah Hill, Sea Ranch, and Pescadero

Rocks. Although the holdfasts of these macrophytes typically occupied relatively little of the substratum, the fronds of each thallus typically overlaid fairly large areas of the rocky surfaces.

The rockweed Fucus gardneri occurred only at Kibesillah Hill (22 percent cover) and Sea Ranch

i (18 thesepercent). rockweedsThecovered rockweeds fairlyPelvet largeia/Pelvetiopsis areas of the substratum sp(p), were(21observed percent cover) at threeonly sites.at However, Pescadero

Rocks, whereas their cover at Sea Ranch and Kibesillah Hill was considerably less (3 percent and

I lassemblage ess than 2 perc at Point ent, reSierra spectivNevada. ely). No rockweeds were observed in the Endocladia/Mastocarpus

I Only four maeroinvertebrates covered more than 2 percent of the substratum: the barnacles Chthamalus sp(p). (8 percent) at Point Sierra Nevada, the sea anemone Anthopleura

elegantissima (7 percent) at KibesiUah Hill, the littorine snails L/ttor/na scutulata/plena (6

_ percen0 at Point Sierra Nevada, and the seastar Pisaster ochraceus (2 percent) at Sea Ranch

(Table 27). Anthopleura elegantissima was not observed at the two southernmost sites,

Pescadero Recks and Point Sierra Nevada, whereas Chthamalus sp(p), were not observed at

I Pescadero Rocks. Littorina scutulata/plena were not observed at either Sea Ranch or Pescadero Rocks.

'! Due to their small size, grazers usually did not occupy large areas of substratum at the four sites

and were better assessed by determining their density (no J0.1875 m2). The littorine snails

i Littorina scutulata/plena were most abundant in terms of density at Point Sierra Nevada (685) and Pescadero Rocks (103) (Table 28). Limpets were more abundant at Sea Ranch (79)

andPescadero Rocks (31) than at the other sites. The snail Tegulafunebralis was fairly abundant

i asites t Kibe(less siUahthanHill 3).(1C0hitons ), not owbserv ere oednlyatcommon Sea Ranch, at Peseadero and at veryRocks low den (unidentified sities at thePolyplacop two southheora, rn

4). Predatory snails and sea stars occurred at very low densities or were absent at all four sites.

I The most obvious pattern in the Endocladia/Mastocarpus assemblage from 1985-1992 was that

both Endocladia and Mastocarpus consistently remained the two most abundant maerophytes at

the three southernmost study sites (Tables A-15, 12, and A-28). However, at Kibesillah Hill, Endocladia and the rockweed Fucus gardneri have been the two most abundant maerophytes

(Table A-7) since the start of the study in 1985. Mastocarpus usually ranked fifth in macrophyte

I abundance at this site.

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87

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I

Table 28. The more abundant (>3/0.1875 m :) grazers in the Endocladia/Mastocarpus assemblage control •

plots at the four study sites during fall 1992.1

i

Kibesillah Sea "Pescadero Point Sierra 1

Taxon Hill Ranch Rocks Nevada

i

i

Littorines 30.6 103.0 685.4 I

Limpets 18.2 78.9 31.4 <3 i

m

Tegulafunebralis 10.3 <3 <3

Polyplacophora, unident. - 4.2 I

] Dataa_meamofthreeplets(n=3). Gtazersarerankeda_umtngto themeansatKibesillahHill.Adash(-)indica_ thegrazerwasaot

tectmied at that site. i

I

Several other trends were apparent when comparing the fall 1992 data to that collected in

previous fall sampling periods. A general downward trend in total macrophyte cover was evident m

at Kibesillah Hill, Pescadero Rocks, and Point Sierra Nevada (Tables A-7, A-21, and A-28). The 11

greatest decrease was at Point Sierra Nevada, where macrophyte cover went from 66 percent in

1985 to 35 percent in fall 1992 (Table A-28), due to a reduction in Endocladia muricata and •

Mastocarpus papillatus. This site also had a large reduction in the total number of macrophyte 1

taxa from 6 in 1985 to only 2 in 1992. Also at Point Sierra Nevada, macrophyte cover tended to

cycle among years with a cover maximum around 65 percent and a minimum around 35 percent. •

Mastocarpus papillatus showed 2-year fluctuations in cover over the course of the study. At I

Kibesillah Hill (Table A-7), where total macrophyte cover dropped since fall 1989 (from 148 to

89 percent), the decline was due to approximately 50-percent reductions in the cover of three •

macrophytes: the fleshy red alga Mastocarpus papiUatus, the tufted green alga Cladophora

columbiana, and the roekweed Fucus gardneri. Furthermore, the rockweeds

Pelvetia/Pelvetiopsis sp(p), at this site have precipitously dropped in cover from 22 percent in i

fall 1989 to less than I percent in fall 1992. KLI also reported (Table A-7) a drop in cover of

these rockweeds between 1987 (24 percent) and 1988 (6 percent). These trends may indicate a

natural fluctuation for these taxa. At Pescadero Rocks (Table A-21), total macrophyte cover II

declined by about one-third (from 198 percent in 1985 to 125 percent in 1992). Endocladia

muricata, Mastocarpus papiUatus, and crustose coraUines were the main macrophytes 1

contributing to this decline. Total mac_phyte cover at Sea Ranch (Table A-15) has increased i

from 103 percent at the start of the study in 1985 to 128 percent in 1988, and it has remained

I

about the same since 1988 with 131 percent cover in 1992. !

In contrast, there were few trends in macroinvertebrate cover patterns. However, at Pescadero

Recks (Table A-21) there has been a decline in total macroinvertebrate cover since 1985 (from I

!

88

!
I 12 percent in 1985 to 2 percent in 1992). This reduction is primarily due to declines in barnacles, littorine snails, and mussels.

I The Bray-Curtis index of similarity values (fall 1992) for the Endocladia/Mastocarpus assemblage at all four study sites remained within the range of similarities calculated for each

site for previous years (Figures 3, 5, 7, and 9). Therefore, the control plots in fall 1992 were

about similar to each other had been in

as as

they previous years.

The differences described above in species richness and abundance in the Endocladia/

I Mastocarpus assemblage at the four sites were not surprising. There are many site-specific

differences (e.g., biological, physical, anthropogenic) that may cause variations in this

i cover assemblinathis ge amassemblage ong sites anatdPoint over Sierra time. NHowevadaever,andthetheverygeneral low spe downward cies richness trendsanind tmacrophyte otal biotic

abundance at three of the four sites are of interest and will be closely assessed in the future to

i de intere termin st, esince wheitht ehrasthdeeseclinetredndsor cunondetinrgueone. Chsubs angetantial in Mast fluctocarpus uation aabun t threedance sitesisanodf pisarticular one of the

two "indicators" of this assemblage.

!

C. Conclusion

I Results from fall 1992 showed that, after 71⁄2 years, none of the mussel assemblage plots that

were cleared by Kirmetic Laboratories, Inc., had recovered completely. However, recovery is

I proceeding at a very low rate. In fall 1992, the cleared plots were more similar to the control plots than they were during the last survey by KLI, and mussel abundance was greater. Although

it is not possible at this time to determine how long recovery will actually take, complete

I of the spring- and fall-cleared mussel plots at all of the sites will probably take several

recovery

more years. The MMS plans to continue to monitor these plots every 2 years until recovery takes

i place.

The study of undisturbed mussel and algal assemblages indicates that, although these

i asse humanmbldi ages s persist and are usually fairly stable over time, changes can occur due to natural or

turbances. For example, mussel abundance in the control plots increased at one site

and decw.ased at another site. Additionally, there has been a general downward trend in algal

abundance considerablyatlothwreeer ofin tshpec e foieurs ricsithnes ess andandthe algal algal abassemundablnceagecomat onpared e sitetowtheas foothunerd sitotebes. These

trends will be closely monitored every 2 years to determine whether they continue.

!

!

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89

I

'1

i
I

V. REFERENCES I

Abbott, I.A., and G.J. HoUenberg. 1976. Marine algae of California. Stanford University m

Press, Stanford, California. 827 pp. m

Abbott, I.A., and J.N. Norris. 1985. Taxonomy of economic seaweeds with reference to some m

Pacific and Caribbean species. California Sea Grant College Program, University of t

California, La Jolla, California.

Bayne, B.L. 1976. Marine mussels: Their ecology and physiology. Cambridge University m

Press, Cambridge, Massachusetts.

m

Bray, J.R., and J.T. Curtis. 1957. An ordination of the upland forest communities of southern m

Wisconsin. Ecological Monographs 27:325-349.

Castenholz, R.W. 1967. Stability and stresses in intertidal populations. Pp. 15-28/n, T.A. m

Olson and F.J. Burgess (eds.), Pollution and marine ecology. Interscience Publishers,

New York. m

Chan, G.L., and A. Molina. 1969. The conservation of marine animals on Duxbury Reef. m

College of Matin, Kentfield, CA. 56 pp. m

Cimberg, R.L. 1975. Zonation, species diversity and redevelopment in the rocky intertidal near m

Trinidad, northern California. Master's thesis, Humboldt State University, Arcata, m

California. 118 pp.

Connell, J.H., and R.O. Slatyer. 1977. Mechanisms of succession in natural communities and m

i their role in community stability and organization. American Naturalist 3:1119-1144.

Dayton, P.K. 1971. Competition, disturbance and community organization: The provision and m

subsequent utilization of space in a rocky intertidal community. Ecological Monographs

41:351-389. m

Foster, M.S., c. Harrold, and D.D. Hardin. 1991. Point vs. photo quadratestimates of the

cover of sessile marine organisms. Journal of Experimental Marine Biology and Ecology m

149:193-203.

Glynn, P.W. 1965. Community composition, structure, and interrelationships in the marine n

intertidal Endocladia muricata-Balanus glandula association in Monterey Bay, m

California. Beanfortia 12:1-198.

Goodall, D.W. 1978. Sample similarity and species correlation. Pp. 99-149 in, R.H. Whittaker m

(ed.), Ordination of plant communities. W. Junk, The Hague. mI
i Hewatt, W.G. 1935. Ecological succession in the Mytilus californianus habitat as observed in Monterey Bay, California. Ecology 16:244-251.

I Hommersand, M.H., M.D. Guiry, S. Fredericq, and G.L. Leister. 1993. New perspectives in the taxonomy of the Gigartinaceae (Gigartinales, Rhodophyta). Hydrobiologia

260/261:105-120.

!

Kanter, R.G. 1976. Quantitative analysis of Mytilus californianus community structure and

i diversity. Ph.D. dissertation. University of Southern California, Los Angeles, California.

Kanter, R.G. 1980. Biogeographic patterns in mussel community distribution from the Southern

California Bight. Pp. 341-355 in, D.M. Power (ed.), The California Islands: Proceedings

I of a multidisciplinary symposium. Santa Barbara Natural History Museum, Santa

Barbara, California.

I Kinnetic Laboratories, Inc. 1986. Study of the rocky intertidal communities of Central and

Northern California. Year I, Volumes 1-2. Prepared in association with the University of

I Cali for thfoernia, U.S.SDanta eparCtment ruz, Moss of theLanding Interior,MMinerals arine Laborat Managem ories,entandSMon ervice, terePaci y Bfiayc OACquSarium

Region. Contract No. 14-12-0001-30057. OCS Study MMS 86-0051

I Kinnetic Laboratories, Inc. 1992. Study of the rocky intertidal communities of central and

northern California. Final Report, Volumes I-HI. Prepared in association with the

I University of California, Santa Cruz, Moss Landing Marine Laboratories, and TENERA

Corporation for the U.S. Department of the Interior, Minerals Management Service,

Pacific OCS Region. Contract No. 14-12-0001-30057. OCS Study MMS 91-0089.

I Kozloff, E. 1987. Marine invertebrates of the Pacific Northwest. University of Washington

Press.

!

Lindberg, D.R. 1986. Name changes in the "Acmaeidae." The Veliger 29(2):142-148.

I National Research Council (NRC). 1989. The adequacy of environmental information for outer

continental shelf oil and gas decisions: Florida and California. National Academy of

i Sciences. National Academy Press, Washington, D.C. 86 pp.

Paine, R.T. 1974. Intertidal community structure: experimental studies on the relationship

I between a dominant competitor and its principal predator. Oecologia 15:93-120.

Paine, R.T., and S.A. Levin. 1981. Intertidal landscapes: disturbance and the dynamics of

I pattern. Ecological Monographs 51:145-178.

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!

Pielou, E.C. 1984. The interpretation of ecological data: A primer on classification and 1

ordination. John Wiley, New York/263 pp.

II

Richards, J.B. 1992. Mussels. In: W.S. Leet, C.M. Dewees, and C.W. Haugen (eds.), i

California's living marine resources and their utilization. California Sea Grant Extension

Publication. !

Ricketts, E.F., J. Calvin, J.W. Hedgpeth, and D.W. Phillips. 1985. Between Pacific tides.

Fifth edition. StanfordUniversity Press, Stanford. 652 pp. II

m

Scagel, R.F., P.W. Gabrielson, D.J. Garbary, L. Golden, M.W. Hawkes, S.C. Lindstrom, J.C.

Oliviera, and T.B. Widdowson. 1989. A synopsis of the benthic marine algae of British •

Columbia, Southeast Alaska, Washington, and Oregon. University of British Columbia,

Phycological Contribution No. 3. Vancouver, British Columbia. 532 pp,

1

Silva, P.C. 1990. Hesperophycus setchell & gardner, nom. cons. prop., a problematic name II

applied to a distinctive genus of Fueaceae (Phaeophyceae). Taxon 39:1-8.

Smith, R.I., and J.T. Carlton (eds.). 1975. Light's Manual: Intertidal invertebrates of the central •

California coast. Third edition. University of California Press, Berkeley. 416 pp.

Stranghan, D., and R.G. Kanter. 1978. Mussel community study. Southern California Baseline •

Study, Final Report, Vol. HI, Report 2.2. Year 1. Submitted to BLM Washington D.C. !

Suchanek, T.H. 1979. The Mytilus californianus community: Studies on the composition,

structure, organization, and dynamics of a mussel bed. Ph.D. Dissertation, University of 1

Washington, Seattle. 286 pp. II

Vesco, L.L., and R.M. Gillard. 1980. Recovery of benthic marine populations along the Pacific •

coast of the United States following natural and man-made disturbances including 1

pertinent life history information. U.S. Department of the Interior, Bureau of Land

Management, Pacific OCS Region. POCS Reference Paper No. 53-4. 50 pp. I

I

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Z0m I!I!IIIII!IIIIIII
IIIIIII| VI

.APPENDIX

IIIIII

'lII

93

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LIST OF APPENDIX TABLES

A-1 Macrophyte, maeroinvertebrate, and substratum abundances in the Mytilus I

assemblage control plots at Kibesillah Hill for fall sampling periods

from 1985 to 1992 ................................................... 97 !

A-2 Macrophyte, macroinvertebrate, and substratum abundances in the Mytilus mm

assemblage control plots at Kibesillah Hill during spring 1991 ................ 99 !

A-3 Macrophyte, macroinvertebrate, and substratum abundances in the Mytilus m

assemblage spring-cleared plots at Kibesillah Hill for fall sampling

periods from 1985 to 1992 ........................................... 100

A-4 Macrophyte, macroinvertebrate, and substratum abundances in the Mytilus I

assemblage cleared plots at KibesiUah Hill during spring 1991 ............... 102

A-5 Summary of Mytilus cover, density, and recovery rate in spring 1991 .......... 104 I

A-6 Macrophyte, macroinvertebrate, and substratum abundances in the Mytilus •

assemblage fall-cleated plots at Kibesillah Hill for fall sampling periods

from 1986 to 1992 .................................................. 105

I1

A-7 Macrophyte, macroinvertebrate, and substratum abundances in the I

Endocladia/Mastocarpus assemblage control plots at Kibesillah Hill

for fall sampling periods from 1985 to 1992 ............................. 107 I

A-8 Macrophyte, macroinvertebrate, and substratum abundances in the

Endocladia/Mastocarpus assemblage control plots at Kibesillah Hill during I

spring 1991 ....................................................... 109

I

A-9 Macrophyte, macroinvertebrate, and substratum abundances in the Mytilus I

assemblage control plots at Sea Ranch for fall sampling periods from

1985 to 1992 ...................................................... 111

A-10 Maerophyte, maeroinvertebrate, and substratum abundances in the Mytilus

assemblage control plots at Sea Ranch during spring 1991 ................... 113 R

A-11 Maerophyte, maeroinvertebrate, and substratum abundances in the Mytilus

assemblage spring-cleared plots at Sea Ranch for fall sampling periods •

from 1985 to 1992 .................................................. 1I5

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94 !
I LIST OF TABLES (Continued)

A-12 Macrophyte, macroinvertebrate, and substratum abundances in the Mytilus

I assemblage cleared plots at Sea Ranch during spring 1991 .................. 1I7

A-13 Macrophyte, macroinvertebrate, and substratum abundances in the Mytilus

I assemblage fall-cleared plots at Sea Ranch for fall sampling periods from 1986 to 1992 .................................................. 119

I A-14. Macrophyte, macroinvertebrate, and substratum abundances in the

Endocladia/Mastocarpus assemblage control plots at Sea Ranch

i during spring 1991 ................................................. 121

A- 15 Macrophyte, macroinvertebrate, and substratum abundances in the

i Endoclad samplingia/Mast periodsocarpus from 1985assemto b1992 lage con................................... trol plots at Sea Ranch for fail 123

I A-I 6 Mac assemrobphlageyte,conmactroroin l plovetrtseabrtaPte, escadanedrosubs Rocks tratufomr abfaunll samdanpcelins ginpthereiodMytilus s

from 1985 to 1992 .................................................. 125

I A-17 Macrophyte, macroinvertebrate, and substratum abundances in the Mytilus

assemblage control at Peseadero Rocks during spring 1991 ................. 127

I A- 18 Macrophyte, macroinvertebrate, and substratum abundances in the Mytilus

assemblage spring-cleared plots at Peseadero Rocks for fall sampling

I periods from 1985 to 1992 129

A-19 Macrophyte, maeroinvertebrate, and substratum abundances in the Mytilus

I assemblage cleared plots at Peseadero Rocks during spring 1991 ............. 131

i A-20 Macrop assemblaghyete,

famall-cleroinv earederpleblotrsatate,Panesdeadero substratum Rocksabforundan fall ces saminplingthe Mytilus periods

from 1986 to 1992 .................................................. 133

I A-21 Macrophyte, macroinvertebrate, and substratumabundances in the

Endocladia/Mastocarpus assemblage control plots at Peseadero Rocks

I for fall sampling periods from 1985 to 1992 ............................. 135

A-22 Maerophyte, maeroinvertebrate, and substratum abundances in the

I Endocladia/Mastocarpus assemblage control plots at Pescadero Rocks during spring 1991 ................................................. 137

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95

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I
!

mR

LIST OF TABLES (Continued) I

A-23 Macrophyte, macroinvertebrate, and substratum abundances in the Mytilus m

assemblage control plots at Point Sierra Nevada for fall sampling periods

from 1985 to 1992 .................................................. I39

A-24 Macrophyte, macroinvertebrate, and substratum abundances in the Mytilus I

assemblage control plots at Point Sierra Nevada during spring 1991 ........... 141

_m

A-25 Maerophyte, macroinvertebrate, and substratum abundances in the Mytilus !

assemblage spring-cleared plots at Point Sierra Nevada for fall sampling

periods from 1985 to 1992 ........................................... 143 I

A-26 Macrophyte, macroinvertebrate, and substratum abundances in the Mytilus

assemblage cleared plots at Point Sierra Nevada during spring 1991 .......... 145 I

A-27 Macrophyte, maeroinvertebrate, and substratum abundances in the Mytilus

assemblage fall-cleared plots at Point Sierra Nevada for fall sampling R

periods from 1986 to 1992 ........................................... 147 ==

A-28 Macrophyte, maeroinvertebrate, and substratum abundances in the I

Endocladia/Mastocarpus assemblage control plots at Point Sierra Nevada

Illl

for fall sampling periods from 1985 to 1992 .............................. 149

!

A-29 M_-mphyte, _invertebr_e, and substratum abundances in

Endocladia/Mastocarpus assemblage control plots at Point Sierra Nevada •

during spring 1991 ................................................. 151 |

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96

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IIIIII

m

IIIIIIIIIIIII
I Table A-1. Macrophyte plots at Kibe,sillah macroinv Hillertforebrat falle,sampling andsubstratum periods from abundanc 1985etos in1992. the 1Mytilus assemblage control

i Overall Taxon/Substratum 1985 1986 1987 1988 1989 1992 Mean

I Maerophytes-Cover(Percent)

Porphymperforata 3.3 0.6 24.4 37.8 - - 11.2

I Por Endocladi phyralaa muri nceolata cata 1-.1 2-.2 1.1 0.6 235.0.3 1-2.2 3.3.79

Mastocarpus papi//atus 1.1 - 2.2 3.9 2.8 10.6 3.4

i Porphyra sp(p). 8.9 .... 1.5 Crustoscoe rallinuenis,dent, i.1 - 0.6 - 0.3

Petrocelis sp(p). - 0.6 - - 0.1

lridaea splendens - 0.6 - -

I Ra_/a sp(p). - 0.6 - - -

TotalMacrophyteCover 15.5 4.0 28.3 42.9 31.1 22.8

I Maeroinvertebrates - Cover (Percent)

btytilus californianus 90.6 96.7 91.7 97.2 100.0 98.9 95.9

I Ba/anus 2.8 9.4 6.1 5.0 6.1 5.0 5.7

g/andu/a

Anthopleura elegantissima 6.1 1.7 9.4 3.9 0.6 10.6 5.4

Otthama_ sp(p). 4.4 1.7 4.4 1.1 1.1 13.3 4.3

I Teg Smibalanus ulafunebralis cariosus 2. 1.87 0.- 6 01.1.6 0.6 1.7 4.4 06 1.1- 01.7.9

"ColliseUa"scabra - 0.6 1.1 0.6 1.1 - 0.6

I Littorina scutulaudplena - - 0.6 1.7 0.6 0.5 Lottia digitalis 0.6 0.6 0.6 0.6 0.4

Lott/a parag/g/ta//s - 0.6 0.6 - 0.2

NuceUaemarginata - - 0.6 - - 0.1

Strongy/ocentrotus - - 0.6 - - 0.1

purpurams

TotalMacroinvertebrateCover 109.0 111.9 116.2 111.3 t15.6 130.1

I Macroinvertebrates - Density (No./0.1875 m_

l Littorina scumlata/plena 14.6 70.6 30.8 13.7 13.3 21.4 27.4 Tegulafunebralis 31.0 18.7 19.7 17.7 38.1 28.3 25.6

"ColliseUa"$cabra 19.3 8.2 7.4 19.3 17.3 10.8 13.7

Lottiadigitalis 29.4 7.8 11.1 9.2 2.7 7.0 11.2

I Lott/a pe/ta 30.7 1.7 6.7 4.1 0.7 7.3

Lottiaparadigitalis 9.0 9.2 2.3 12.3 0.7 5.6

Lott/a sp(p). 12.5 16.7 4.9

I NuLott/a cellal/matu/a emarginata 2. 2.80 1.7 3.3- 0.3 1.7 0.7 2.4 01..96

Lot//a asm/ 0.3 - - 0.7 0.3 0.2

I

97

!

!
I

Table A-1. Macrophyte, macroinvertebrate, and substratum abundances in the My_us assemblage control I

plots at Kibesmah Hill for fall sampling periods from 1985 to 1992.x (continued)

Taxon Overall I/Substratum 1985 1986 1987 1988 1989 1992 Mean

Macroinvertebrates - Density (No.I0.1875 m2) I

Strongylocentrotuspurpurams - 0.7 - - 0.2

Tectura Echinodscumm erm - 0.7 0.3 - - 0.2 ! ,unident. - - - 0.3 0.1

L/ttor/na keenae 0.3 - - 0.1

Total Number of Macrophyte Taxa 5 4 4 4 3 2 I

Total Nmber of Macroinvertebrate Taxa 13 15 15 13 12 12

Total Number of All Taxa 18 19 19 17 15 14 I

Substrata - Cover 0Perceat) I

Shell debris 4.4 1.1 6.1 1.1 3.3 1.7 3.0

Rock 1.7 - 0.6 - 0.4 I

Bare Rock 0.6 - 0.6 - 0.2

Sand - 0.6 - 0.2

1985-1989 data are from Khme_ I.al_ramries, Inc. (1992). Dalaaremeansof_eepiots(n=3). Taxa and mbsuma within each I

calegory are nmk_ according to overall means, then listed alphabetically if the overall means are equal. Total percent cover can exceed I00

perceat because nmltiple layers were sampled. A dash (-) indites the laxcHn/subslraann was not recorded during that sampling period. I

I

I

I

I

I

I

9s I

I
I Table A-2. Macrophyte, the My_lus assemblage macroinvertebrate comrol p, land ots atsubstratum Kibesillababundances Hill during in

spring 1991.1

I Standard Taxon/Substratum Mean Deviation

I Macrophytes - Cover (Percent)

I Endoc/od/a Mastocarpusmur/cata papillatus 206.7.6 61..77

TotalMacrophy_eCover 27.3

I Macroinvertebrates - Cover (Percent)

I MBa/anus ytilus californ g/andu/aianus 97.2 4.4 2.6 2.6

Teguiafunebralis 3.9 1.0

I Amhopleum "CoUisella"scabra 1.7 1.7

elegantissima 1.1 1.9

sp(p). 1.1 1.0

Lottia digitalis 1.1 1.9

Semibalanus cariosus 0.6 1.0 Linorina scutulata/plena 0.6 1.0

I Total MacroinvertebrateCover I11.7

Macroinvertebrates - Density (No.t0.1875 mz)

I "CoUiseUa"scabra 30.8 5.7

Tegulafunebralis 23.3 23.2

l.,iuorinascutulata_lena 15.3 4.5

I Lonia d/s/ta//s 7.0 12.i

/.ou/a sp(p). 4.2 7.2

Lott/a pe/ta 0.3 0.6

I Total Nmber of Macrophyte Tara 2

i Total Nmber of Macroinvertebrate Tan 11 Total Number of All Taxa 13

I Substrata - Cover (Percent)

Shelldebris 4.4 3.9

I Bare Rock 0.6 1.0

' Dataare f]rmnKinneticLabocatofies,lnc.(1992). Dataaremeamofth.reepiots(n-3). Taxa andsubstrata

I w'ilhinmu:hcaXcgoryare _ accotdh_ w I_ mcam, [hcnlisted _dradly if m,',xm_amm'e_. Total

IXm:_mco,,,u-¢.ane_._l 100 l_-cem l_.am_ nmlti_ l_cn winem'aplcd.

99

!

I
I

in

Table A-3, Macrophyte, macroinvertebrate, and substratum abundances in the My_us assemblage spring-cleared plots •

at Kibesillah Hill for fall sampling periods from 1985 to 1992)

|

Taxun/Substratum 1985 1986 1987 1988 1989 1992 Mean

Macrophytes - Cover (Percent) n

Mastocarpuspapi_ - 15.6 37.2 14.4 23.3 I0.0 16.8

Endoc/ad/a mur/cata 1.1 8.3 17.8 13.3 9.4 8.3 9.7

Neorhodomela oregona 3.9 30.0 23.9 9.6 •

Cladophora columbiana I. 1 12.2 12.2 24.4 8.3

Odontha//a floccosa 1.7 1.7 24.4 4.6

Iridaea heterocarpa 11.1 11.1 1.1 3.9 4.5 Ill

Fucus gardneri - 0.6 7.2 5.0 2.1 •

Iridaea splendens 1.1 3.9 4.4 3.3 2.1

Potysiphonia hendryi I. 1 2.8 5.0 2.2 1.9

CoraUina vancouver/ens/s - 1.I 0.6 7.8 1.6 I

Crustose eorallines, unident. 1.1 3.9 1.7 0.6 1.1 1.4 I BossieUa plumosa 1.7 2.8 0.6 0.9

Pelvetia-Pelvetiopsis sp(p) - 3.3 1.7 0.6 0.9

Neorlwdomela larix - 5.0 0.8 •

Ana//pus japon/cus - 2.8 0.6 - 0.6 i

GATGOR 3.3 - 0.6

Halosaccion americanum - 2.2 1.1 - 0.6

Perrocelis sp(p). 1.1 1.7 0.5 !

Brown crusts - 1. I 0.2

RMfs/a sp(p). 0.6 0.6 0.2

Red crusts 0.6 0.6 0.2 n

G/gart/na cana//cu/ata 0.6 0.1 •

Mastocarpus jardinii - 0.6 O.1

I

Microcladia borealis - 0.6 - 0.1

Polys_t_honia sp(p) - 0.6 - 0.1 •

Red blades 0.6 - - 0.1 1

Total Macrophyte Cover 5.0 29.0 84.0 101.1 91.8 100.0

I

Maero_certebrates - Cover (]Percent) 1

Ba/anus g_ 5.0 21.1 13.9 5.6 0.6 1.7 8.0 I

Myt//us ca//forn/an_ 0.6 1.1 1.1 8.3 3.9 21.1 6.0 •

Ouhama/us sp(p). 7.8 7.2 1.1 0.6 1.1 5.6 3.9

Anthopleura elegantissima 1.1 1.1 2.8 1.1 2.2 1.4

Tegulafunebralis 2.8 0.6 1.1 0.6 1.1 1.0 •

Linorina scumhua/plena 1.7 2.8 0.8

Tetracfita n_enscens 3.9 0.6 0.8 1

"Co///se//a" scabra 0.6 0.6 2.8 0.7

Sem/ba/anus car/osus - 1.1 0.6 2.2 0.7 •

Lou/a d/g/ta//s 1.1 1.1 - 0.4 1

Pagurussp(p) 0.6 - 0.6 0.2

Anthop/euraxanthogramm/ca - - 0.6 0.I

Littor/na keenae 0.6 - 0.1 •

Lottia paradigitalis - 0.6 0.1

Nuttalina californica 0.6 - 0.1

Polli cipes polymerus - - 0.6 0.t l

!

I00 I
I

Table A-3. Macrophyte, macroinvertebrate, and substratum abundances in the Mytilus assemblage spring-cleared plots

at Kibesillah Hffi for fall sampling periodsfrom 1985 to 1992: (continued)

I Overall

Taxon/Substratum 1985 1986 1987 1988 1989 1992 Mean

l Macroinvertebrates - Cover (Percent)

I Total MacroinvertebrateCover 21.4 34.4 18.9 24.1 12.9 33.5

Macreinvertebrates - Density (No./0.1875 m2)

Littorina Lott/a sp(p). scutulata/plena 112.5 367 5142.0 76.8 187.0843 79. 33 73 336. 7.45 204..82 17590.2.1

"Collisella"scabra 32.4 44.3 24.3 48.2 61.0 22.3 38.8

i Loftia digitalis 25.9 47.9 5.7 9.8 9.8 1.0 16.7

Tegulafunebralis 27.4 3.7 7.7 4.3 13.1 8.0 10.7

Loct/ape/ta 23.8 0.3 5.5 3.7 2.3 1.7 6.2

Loffia paradigitalis 2.1 5.3 10.3 5.3 3.0 3.1 4.8

Nucella emarginata 0.3 2.0 5.8 1.7 2.4 4.2 2.7 dmph/ssa co/w_/ana - 6.5 1.I

Nutta///na ¢_forn/ca 1.0 0.3 1.7 0.7 0.6

Liralaria succinta - - 2.1 0.4

l _ asm/ 2.4 - - 0.4

Lott/a//matu/a 2.0 - - 0.3 0.4

Ocenebra c/rcumtexta - 2.1 0.3 0.4

Lepidochitona dent/ens - 1.0 1.0 0.3

Amphissa Cottidae,unid versicolor ent 00.7.3 -- 0.3 0.3 0.2 O.1

Lepidochitona _gii - 0.3 0.1

_m_er_ sp(p). - - 0.3 0.1 Mopa//a muscosa - - 0.3 0.3 O.1

Tectmrascunon 0.3 O.1

ToniceUalineata 0.3 - - O.1

I Tetal Number of Macrophyte Tan 3 8 10 15 16 16

Total Number of Macroinve_brate Tram 17 15 18 18 17 18

Ii

I | Total Number of All Tan 20 23 7,8 33 33 34

i Substrata Bar -Cover(Percmt) e Rock 73.9 48.3 22.2 15.6 23.3 7.2 31.8

Rock 5.6 16.1 42.8 35.6 42.2 29.4 28.6

I Sand 0.6 2.2 0.6 0.6

Shell debris 1.7 - 1.1 0.5

I t 1985-198data 9 refrom_ Laboratories, Inc(199 . 2).Dataaremeansofthreepint(snffi3Tax).aandsubstrata withineach

categoryarerankedaccordingto overallmeans,thenlistedalphabeticallyfftheoverallmeansareequal.Totalpercentcovercanexceed100

percentbecausemultiplelayersweresampled.A dash(-) indicateths elaxon/subsUannnwasn_ recordedduringthatsampli_period.

!

101

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1

Table A-4. Macrophyte, macroinvertebrate, and substratum abundances in the Mytilus assemblage •

cleared plots at Kibesillah Hill during spring 1991. _

J

Taxon Spr_lear_ FalI-Clear_ !/Su_um Mean S.D. 2 Mean S.D.

Macrophytes - Cover (Percent) l

Neorhodomela larix 32.8 44.4 1.7 2.9

Endoc/ad/a mur/cata 13.9 17.4 1.7 1.7 l

Mastocarpus papi//atus 7.2 9.8 7.2 1.0

R_ _). 5.6 1.0 7.2 5.4

Cladophora columbiana 4.4 3.8 29.4 1S.0 •

Crustose corallines, unident. 4.4 7.7 2.2 3.8 1

Bossiella plumosa 3.9 5.4 2.8 4.8

Corallina vancouveriensis 3.9 4.2 8.3 6.0 al

lridaea splendens 3.9 4.2 2.2 1.9 1

Analipusjaponicus 3.3 4.4 2.8 1.0 I

Fucus gardneri 2.2 3.9 16.7 13.6

Petrocelis sp(p). 2.2 3.8 0.6 1.0 1

Odonthalia floccosa 1.1 1.0 1.1 1.9

Polysiphonia hendryi 1.1 1.9

Cylindrocarpus rugosus 0.6 1.0 •

Iridaea heterocarpa 0.6 1.0 0.6 1.0 1

Prionitis lanceolata 1.1 1.9

Total Macr_h_ Cover 91.1 85.6 !

_inv_es - Cover (Percent)

Ill

Mytilus californianus 18.3 13.2 16.7 4.4 I

_ 2.2 3.8 0.6 1.0

Tegulafunebralis 2.2 3.9 4.4 6.3 •

Anthopleura elegantissima 1.1 1.9 1.1 1.0 I

Nuualina californica I. 1 1.0 -

&_ 0.6 1.0 2.8 3.5 I

Semibalanus cariosus - 1.1 1.9 •

Anthopleura xanthogramica - 1.1 1.9

1

__ _). - 2.8 4.8

"_e_" s_ra - 0.6 1.0 •

Littorina scumlma/plena - 0.6 1.0 1

z_,a/am_//_taUs - 0.6 1.0

Phragmatopoma californica - 0.6 1.0 1

Te_ac_m n_enscens - 1.7 2.9 1

Total Macromve_ Cover 25.5 34.7

!

I

102 I
I Table A-4. Macrophyte, cleared plots macroinvert at Kl_esillahebrat Hille, during and substratum spring 1991abundances : (continued) in the Mytilus assemblage

i Spring-Cleared Fall-Cleared

Taxon/Substratum Mean S.D. _ Mean S.D.

Maeroinvertebrates - Density (No./0.1875 nr_)

/.ott/a sp(p). 50.0 81.3 52.1 43.9

I Lottia Teguladigitalis funebralis 4623..18 4224.7.1 2319.7.7 2283..05

"ColliseIla" scabra 17.1 12.0 42.2 30.3

Littorina scutulata/plena 16.0 8.7 5.8 5.0

I 3.7 6.4 0.7 1.2

Lon/a paradigitalis

Lottia asmi 1.0 1.7 -

Nuttallina caIifornica 0.7 0.6 -

I £Mozgpal //a pe/ ia.muscosa ta 0. 0.33 00.6.6 4-.2 7.2

Nuce//a emarg/nata 0.3 0.6 -

i 5trongy/ocentrotus purpuratus 0.3 0.6 -

Total Number of Macrophyte Tan 16 15

I Total Number of Macroinvertebrate Tan 14 15

Total Number of All Tan 30 30

I Substrata - Cover fPercem)

i Rock 38.3 26.0 23.3 13.2

Bare Rock 12.2 5.4 16.7 14.4

Shell debris 3.9 3.5 1.7 2.9

Sand 0.6 1.0 -

!

z Dma_ from_Labotatari_, Inc.(1992). Dmaremeamof_-eeldms(n=3). Tmandmwitlfineachcategowam

i rankedaccorditonthg emeansi-thesl_'i_-cl_v_l plo_, rhelaimxlalplmbetirffth _y mee troareeqml.Temlperce_cover can

_ 100peroembecam_mul_© lay_ w_ _l. A da_ (-)indk_s tt_ Utxon/_tamm wu notr_.on_ inrig plots

2 S.D. ffiStandardDeviation !

i

i

I

103

I

I

l Table A-6. Macrophyt dealedplotse, macroinvertebrate, at KibesilL_ Hill forandfallsubstratum sampling pabundances eriodsfromin1986thetoMy1992 _s )assemblage fallOverall

Taxon/Substratum 1986 1987 1988 1989 1992 Mean

i Macrophytes - Cover (Percent) MastocarpuspapiUatus 8.3 17.2 6.1 17.8 19.4 13.8

Ciadophora columbiana 0.6 16.1 22.2 15.6 10.9

I Ir/daea splendens 21.1 18.9 3.9 5.6 2.8 10.5 Corallina vancouveriensis 0.6 6.7 14.4 7.2 9.4 7.7

Bossieilaplumosa 21.7 0.6 1.7 0.6 4.9

Polysiphonia hendryi 0.6 7.8 13.9 4.5

I Analipus Fucus gardner/ japonicus I. 1 51..61 50.06 6.7 I 1 04.64 22.67

lr/daea heterocarpa - 7.8 2.2 1.7 2.3

Porphyra ianceola_ 10.0 - - 1.7 2.3

Pe Pr/on/t/s/anceo/ata m_ce//ssp(p). 2.2 1.7 2.2 2.2 2.8 5.0 2.2 0.6 1.9 1.9

Crusto_ corallines,unideaL 4.4 I.I 1.7 1.1 1.7

I Odontha//afloccosa - 3.3 2.8 1.7 1.6

Halosaccion araer/cnmun 2.8 3.3 0.6 0.6 1.5

Endoc/ad/a mur/cata 2.2 0.6 1.1 1,1 1.0

I

[ Ra/fa/a sp(p). 1.7 0.6 1.1 0.6 0.6 0.9

! • Red crusts 0.6 - - 0.6 1.7 0.7

I Porphyraperforata 2.2 - 0.6 O.6

Neorhodomela oregona 1.7 0.6 0.5

Microcladia borealis 1.1 1.1 0.4

I Brown Cryptoscrus iphonia ts wood/i -- - 1.1 1.1 0.2 0.2

Neorhodomela larix - - 0.6 0.1

i Pelvnia-Pelvetiopsis sp(p) - - 0.6 0.1

P/ocam/mun ¢/o/aceum - - 0.6 O.1

Total MacrophyteCover 50.6 93.0 83.4 83.1 66.4

I Macroinvertebrates - Cover (Percent)

Ba/anus g/an_ 18.9 2.8 13.9 2.2 1.7 7.9

I My Sem/ba/anus ,i/us c_iforn/anus car/osus 10.6 1.7 - 10. 3.90 19.4 0.6 36.2.0

Chthama/_ sp(p). 1.1 - 0.6 6.1 5.6 2.7

i Tegulafunebralis 0.6 1.1 - 1.7 1.7 1.0

Tetrac/ita rubenscens - - 5.0 1.0

Anthopleura elegantissima 1.1 0.6 2.8 0.9

"CalliseUa"scabm 0.6 - - 1.7 0.5

I _ d/g/ta//s 0.6 1.1 0.6 0.5

L/trot/ha scundata/p/ena 1.1 0.6 - 0.3

Lonia pe/ta - 0.6 0.6 0.2

Nuaa//aaca/from/ca - - 1.1 0.2

I Pagurus Poa/c/pessppot (pymer ) us 0.6 - -- 0.6 0.1 o. 1

i Total MacroinvertebrateCover 22.9 16.2 17.4 27.3 39.7

105

I

I
I

II

Table A-6. Macrophyte, macroinvertebrate, and substratum abmmdances in the Mytilus assemblage fall- •

cleared plots at Kibesillah Hill for fall sampling periods from 1986 to 1992) (continued)

I i

Taxma/Substratum 1986 1987 1988 1989 1992 Mean :

Macroinvertebrates - Density (No./0.1875 m2) !

m

Loraa sp(p). 122.9 50.0 70.8 16.7 8.3 53.7

L/ffor/na xcutu/ata/p/ena 130.2 55.4 16.5 11.0 0.0 42.6 ilmll

"Colliseila" scabra 25.8 3.0 38.0 32.2 32.6 26.3 •

Lottia digitalis 6.8 7.0 35.9 13.4 5.7 13.8

Tegulafunebralis 7.7 10.7 4.7 9.0 9.7 8.4

Lcn_ paradigitalis 7.3 2.3 1.7 9.4 2.7 I

Lo_a _a 4.8 3.1 2.0 3.4 2.7

L/trot/ha keenae 8.3 1.7 1

Nuceila emarginata 2.7 0.3 0.7 0.7

Ocenebra circumtexta 2. I 0.3 0.5 •

Loniaozmi 0.3 0.7 0.3 0.3 1 Nutta///naca//forn/ca 1.0 0.3 0.3 2.0 0.3

Mopalia muscosa 0.3 0.3 - 0.3 0.2

Acanth/na sp(p). 0.3 0.1 l

CorypheUa trilinema 0.3 - 0.1

Leptasterias sp(p). 0.3 - 0.1

_ona _ 0.3 O.1 1

Tectura scutum 0.7 O. 1 1

Total Nnmber of Macrophyte Tan 10 16 18 19 19

Total Number of Macroinvertebrate Tan 12 18 17 15 13 I

Total Nnmber of All Tan 22 34 35 M 32

i

Substrata - Cover (Percent) 1

Bare Rock 41.67 18.33 25.56 20.56 13.3 23.9

Rock 26.67 35.00 I7.78 23.89 12.2 23.1 •

I

Shell debris 0.56 2.22 0.6

I

1986-1989dataare from KinneticLaboratories,Inc. (1992). Data are meansof three plots(n=3). Taxa andsubstratawithin •

each categoryare rankedaccord_ to overalImeans,Iben listeda/I_betically if lhe overall means _ _. Total pcr_m cover

can exceed 100percent becausemultiple layerswere sampled. A clash(-) indicates_hetaxon/substratumwas not recordeddaring

mat_i_ period.

I

I

106 I
I Table A-7. Ma asseremblag ophytee,control macroinv plotsertebrate at Kibe,sillah and substratum Hill for fallabundanc samplingespineriods the Endocladia from 1985/Mastoca to 1992:rpus

i Overall Taxon/Substratum 1985 1986 1987 1988 1989 1992 Mean

Maerophytes - Cover (Percent)

Endoc/ad/a mur/cata 30.6 49.4 25.6 41.7 17.8 17.8 30.5

I Fucusg Oadophardneri ora columbiana 14.49.4 215.7.6 3117.8.1 36.1 25.6 41.1 26.7 2213.2.3 2158.6.6

Pelvetia-Pelvetiopsis sp(p). 7.8 5.0 23.9 5.6 21.7 0.6 10.8

i Mastocarpuspapi//atus 7.2 4.4 5.6 5.6 21.1 11.1 9.2

Petrocelissp(p). 6.1 3.3 17.8 11.7 7.8 7.2 9.0

Ctustose corallines, unident. 2.2 3.9 5.6 4.4 4.4 3.9 4.1

Halosaccion americanum 0.6 - - 3.9 1.7 1.0

I RCoa/fs/a ra///na sp(po_).O_/na//s 1.1 -- 2-.8 0.6- 1.1 5.0 0.9 0.8

Cora///na vancom,er/ens/s - 3.9 1.1 0.8

I lridaea Porphyrasplendens perforata 2.2 0.6 - 2-

.8 0.6- 3.9 00..77

Ir/daea heterocarpa - 1.7 1.1 0.5

Odonthaliafloccosa 2.2 0.4

I Red 0.6 1.7 0.4

BossieUaplumosa 0.6 0.6 - 0.6 0.3

Gel'utiumcoulteri I.I 0.6 - - 0.3

I Neorhodomela Enteromorpha sp(p) oregonia 0.6 -- 1.1 0.6 0. 0.31

lridaea cornucopiae - 0.6 O.1

I Mastocarpusjardinii - 0.6 - O.1

Neorhodomekz/ar/x - - - 0.6 0.1

TotalMacrophyteCover 84.5 96.7 138.7 135.8 147.9 89.0

I Maereinvertebrates - Cover tPercem)

I ACnthopleura _thama/uxsp(p). elegantissima 4.4 9.4 7.8 I. 1 16.- 7 8.- 3 8.3 65.

.07 8.7 2.6

Tegulafunebral_ 1.7 0.6 2.8 1.7 3.9 1.8

i Ba/anus Myt g/andu/a 4.4 1.7 0.6 - 2.8 0.6 1.7 //us ca//forn/angs 0.6 - - 1.7 t. 1 0.6

L/trot/ha saau/am/p/ena 1.7 0.6 - - 0.6 0.5

"CoUisella"scabra 0.6 - - 0.6 0.2

I Loa/ad/g/ta//s - 0.6 - 0.I Lou/apeUa 0.6 - - - 0.1

Lozt/aparad/g/ta//s 0.6 - - O.1

I Semibalanus cariosus 0.6 - - O.1

TotalMacroinvertebrateCover 24.0 12.4 20.7 10.0 17.3 14.0

!

107

!

!
I

Table A-7. Macrophyte, macroinvertebrate, and substratum abundances in the Endoc_Mastocarpus n

assemblage control plots at Kibesmah Hill for fall sampling periods from 1985 to 1992)

(continued)

Overall I

Taxon/Substratum 1985 1986 1987 1988 1989 1992 Mean

n

Macroinvertebrates - Density (No./0.1875 m2) i

Littorina scutulm_plena 333.8 75.9 59.2 19.2 58.8 30.6 96.3 n

Lott/a sp(p). 37.5 4.2 14.6 29.2 25.7 6.3 19.6

Tegulafunebralis 14.0 10.0 15.3 10.0 23.1 10.3 13.8

Lottia digitalis 17.8 19.9 2.8 7.4 1.0 0.3 8.2 •

"Collisella" scabra 13.6 1.0 0.3 4.3 7.8 11.0 6.3

II

Lottia paradigitalis 3.3 0.3 12.1 0.7 2.8

Lottiapelta 5.3 - 2.8 1.3 2.3 2.0 am,

NuceUa emarginata 2.1 O.7 0.3 O.3 0.3 0.7 0.7 •

_ _ - - 0.3 - 2.0 0.3 0.4

Im

_ _m_ - - - 0.3 O. 1

Mopalia muscosa - - - 0.3 O. 1 •

Ocenebra circumtexta - 0.3 - 0.3 0.1

Total Number of Macrophyte Tan 14 10 13 12 12 12 ][

m Total Number of Macroinvertebrate Tara 12 11 11 9 15 12

Total Nmber of All Taxa 26 21 24 21 27 24 n

substrata - Cover (Percent)

Rock 31.7 47.8 32.2 41.1 38.3 18.9 35.0 I

Bare rock 23.9 15.0 7.2 10.6 3.9 27.2 14.6

Shell debris 1.7 - 1.1 0.5 n

SmM - 0.6 - O. i •

n

n 1985-1989dataare fromKinneticLaboratories.Inc.(1992). Dataaremeansofthreeplots(n=3). Taxaandsubstratawithineachcategory •

arcrtnkcdaccordingtooverallm_ans,thcnlistodMp/mbedcallyif theovcndlmeus arcequal Totalpercentcovercanexceed100perccm

becau_multipklayerswc_ sam_d. A dash(-)indicatesthemxon/mbsa_tumwasnotreconiedduringthatsamplingperiod.

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108 I
I Table A-8. Macrophyte, the Endocladia/Mastocarpus macroinvertebrate, assemblage and substratum control plots abundances at Kibesillahn

Hill during spring 1991.1

I Standard Taxon/Substratum Mean Deviation

I Macrophytes- Cover(Percent)

I PeD Endoc/ad/a e_-Pelvegopsis sp(p). 35.0 34.2

.uo'/c.am 30.6 24.1

Mostocarpupaspillams 28.9 34.2

i Fucus gardneri 18.3 18.3

Cladophoracolumbiana i1.7 20.2

Petrocelis sp(p). 6.1 2.6

lr/daea sp/endens 3.9 1.1

Crustos Odom_e/acorallin f_ccoe_s,unident. 32.8.9 2.6 6.7

Ir/daea heterocarpa 1.7 2.9

RaCry_ptos/phon/awood/i 1.1 1.9 /a sp(p). 1.1 1.9

TotalMacrophyteCover 145.1

Macroinvertebrates - Cover(Percent)

I Ouha Tegulamafunebralis /ussp(p). 55.0.0 64..40

Amhop/eura e/egant_s/ma 3.3 2.9

i Liuorina Balanusgscut lanulma/plena dula 31.7 .3 5.8 1.7

"Collisella"scabra 1.1 1.9

caUfo_ 1.1 1.9

Lonia d/g/ta//s 0.6 1.0

Total MacroinvettebrateCover 21.1

Macroinvertebrates - Density (No.10.1875 mz)

L/trOt/hascutu/ata/p/ena 85.6 129.0

Tegulafunebralis 33.0 20.1

"ColliseUa"scabra 21.2 15.0

Lott/a sp(p). 6.3 6.3

Lot l.,off_iaparadigitalis di_ta/is 55.2.8 59..20

Lott/a asm/ 2.8 4.8

Nucella Lott/a pe/taemarginata 0.1.33 0.6 0.6

I

109

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I

Table A-8. Macrophyte, mcroinvertebrate, and substratum abundances in I

the Endocladia/Mastoocarpus assemblage control plots at

Kibesillah Hill during spring 1991.1 (continued)

_d_ ]

Taxon/Substratum Mean Deviation

Total Number of Macrophyte Taxa 12 !

Total Number of Macroinvertebrate Taxa 13 I

Total Number of All Taxa 25

Substrata - Cover (Percent) I

Rock 45.6 2.6

Barerock 10.6 1.0 I Sand 3.3 5.8

t Data are from Kinne_ La_nttories, Inc. (1992). Data are mea_ of three piots (n=3). Taxaand I

within e_h _gory _'_ nmk_ J_.o_ to Ihe m_._, d_-n [i_l _ if the

means an: equal. Total percent cover can exceed 100 percent because multiple layers were sampled. I i

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DO IIIIIIiIi
I Table A-9. Macrophyte, plots at Sea Ranch maeroinvert for fall ebrate, sampling and substratum periods fromabundanc 1985 to e1992 s in) the Mytilus assemblage control

Taxon/Substratum 1985 1986 1987 1988 1989 1992 Mean

I Macrophytes - Cover (Percent)

Endoc/ad/a mur/cata 26.1 23.3 28.9 16.7 15.6 5.6 19.4

I Mast Iridaeaocarpus splendens papillatu$ 4.4 3.3 32.2.3 2.8 2.2 6.7 3.9 1.1 - 2.9 2.1

Petrocelis sp(p). 1.1 1.7 1.7 1.7 1.1 0.6 1.3

i Porphyra perforata 2.2 0.6 0.6 1.1 - 0.8 Porphyra sp(p). 4.4 - - - 0.7

Porphyra lanceolata - 3.3 - 0.6

Ralfsia sp(p). 1.7 0.6 0.6 0.5

I Polysiphonia Analipus japon/cus hendryi 0.- 6 0.6 1.1 1.7 0. 0.43

Egregia menziesii - - I. 1 - 0.2

I CaUithamnion pikeamon 0.6 - - - O.1

Cora///na vancouver/ens/s 0.6 0.1

Crustose corallines, unident. 0.6 0.1

Fucusgardneri - 0.6 O.I

I Ha/osacc/on amer/canmn 0.6 - - - 0.1

Pelvetia-Pelvetiopsis sp(p). - O.6 - O.1

I Total Macrophyte Cover 42.7 34.6 37.4 31.8 23.4 7.9

Macroiavertebrates - Cover (Percent)

I Mytilus californianus 93.9 82.8 88.3 91.7 94.4 93.3 90.7

Pollicipes po/ymerus 3.9 8.3 7.8 6.7 2.2 6.1 5.8

Bahuuts g/andu/a 7.8 7.8 2.2 5.6 0.6 8.9 5.5

I C"Co///se//a 3Mhama/u$" sp(p). scabra 5.6 50..66 50.0.6 33.9.3 2.8 2.8 8.- 9 51.2.3

Lottia digitalis 2.2 - 0.6 1.1 0.7

I ANnthopleura uce//a emargeleg/natantissima a 0.6 0.- 6 -- 0.61.1 0.6 0.24

Littorina scumtata/plena - - 1.1 0.2

i Loltia pelta - - 1.1 0.2 Lott/a _ - - 0.6 - 0.1

/aTtt/aparad/g/ta//s 0.6 - 0.1

Pisaster ochraceus - 0.6 O.1

I Tegula funebralis - 0.6 0.1

Total Macroinvertebrate Cover 114.0 106.3 104.5 114.1 103.4 121.1

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Table A-9. Macrophyte, macroinvertebrate, and substratum abundances in the Myt#.usassemblage control •

plots at Sea Ranch for fall sampling periods from 1985 to 1992.1 (continued) I

Taxon/Substratum I985 1986 1987 1988 1989 1992 Overall Mean I

Macroinvmebrates - Density (No./0.1875 m z) R

"CoUisella" scabra 14.0 17.4 77.5 68.8 89.8 54.8 53.7

Lottia digitalis 88.1 59.0 37.9 26.8 6.3 33.0 41.9

Lo_a _p). 43.8 31.3 72.9 39.6 4.2 104.2 32.0

Lo_a pe_a 21.8 2.0 6.7 10.8 4.7 13.1 9.9

Nucella emarginata 8.3 6.0 8.0 6.0 1.7 3.3 5.6 •

Lo_a para_W_s 6.3 2.0 1.7 3.3 4.1 2.9

Littorina scutulata/plena 2.4 1.3 6.8 0.3 2.8 2.3

Tegulafunebralis 3.0 0.3 1.7 3.0 1.7 - 1.6 am

Gastropoda, un/dent. - 2.1 - 0.4 I /aTtt/a l/matu/a 0.3 0.7 1.0 - 0.3

Leptasterias sp(p). 1.0 - 0.2

Ocenebra circumtexta 0.3 0.7 - 0.2 •

f

P/saster ochraceus - 0.3 - 0.1

Strongy/ocentrotus purpuratus - 0.3 - 0.1

Tecturascutwn 0.3 - - 0.1 I

Total Number of Maerophyte Tan 8 9 7 7 7 3

Toad Number of Macro_ve_ebr_e Tan 12 12 14 18 14 11 I

Total Number of All Tram 20 21 21 25 21 14

ml

Subs_a_ - Cover _ercent) I

Bare Rock 5.0 3.9 1.7 0.6 l.l 2.1 I

Shell debris 1.7 1.1 1.1 3.3 1.7 1.5 1

Rock 0.6 1.7 - 1.7 1.7 0.6 1.1

Sand - - 1.1 - 0.2

!

' 198_1989damat_mKnzficLabon_ofies, h_c.(1992). Dam are meam of _ee plo_ (n= 3). Taxsand_ab_rmw_neach

category are ranked _ m overall means, then _ alphabetically ff the overall means an_ equal. Total _ cover can e_ 100 l

_ because multiple layers were _. A dash (-) _ the _su_ratum was not recorded _ that _I_ _. I

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112 I
I Table A-10. Mac the Mroyphyte, t//us assemblage macroinvertebrate, control plots andatsubSeastratum Ranchabundances during springin

1991.I

Taxon/Substratum Mean Deviation

I Macrophytes - Cover (Percent)

I Endocladia Mastocarpusmuparpillatus icma 138..33 235.8.6

Pelretia-Petveuopsis sp(p). 3.3 5.8

Ra0_ sp(p). 2.2 3.9

I Fucus 1.7 2.9

gardner/

Iridaea splendens 0.6 1.0

Petrocelis sp(p). 0.6 1.0

I TotalMacrophyteCover 30.0

i Maeroinvertebrates - Cover (Percent)

Mytilus californimms 91.7 6.0

Pollicipespolymerus 6.1 2.6

I Ba/anus g/andu/a 3.9 5.4 ¢3Wmma/ussp(p). 3.3 1.7

Loaia digitalis 1.7 1.7

An"ColI _pieu_elara" scabra e/egant/s/ma 0. 1.61 1.90

Tmal_rtebrate Cover 108.4

Maeroinvertebrates - Density (No./0.1875 m2)

"Co///se//a"scabra 93.2 45.3 Lo_2 digita/L_ 9.0 3.0

/.ott/a sp(p). 2.t 3.6

L/ Nutrot/ha cella emarginata scum/ata/p/ena 0.7 0.3 0.6 0.6

Louia paradigitalis 0.3 0.6

Total Number of MaerephyteTan 7

Total Number of Macroinvertebrate Taxa 11

Total Nmnber of All Tan 18

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Table A-10. Macrophyte, macroinvertebrate, andsubstratum abundances in I

the My_lus assemblage control plots at Sea Ranch during spring

1991.1 (continued)

Standard I

Taxon/Substratum Mean Deviation

Substrata - Cover (Percent) I

ShBarelelRock debris 2.2 1.7 2.96 I

Rock 1.1 1.9

Dam arc from Kinncfic Laboratories, Inc. (1992). Data avemeans of threeplots(n=3), Taxaand I

sabstrata withienachcategoraym rankedaccordintgothemeans,thenlistealdphabeticaiflthlye

means are equal. Totalpercentcover canexceed 100 pew,ent because multiplelayers were sampled. I

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114 I

I
I Table A-11. Macrophyt at S e, macrolovertebrate, and substratu_ abundances lo the My#/us assemblage spring-cleared plots ea Ranch for fall sampling periodsfrom 1985 to 1992.5

Overall

I Taxon/Substratum 1985 1986 1987 1_8 1989 1992 Mean

i Macrephyte-sCover(Percent) Ra/_/a sp(p). 16.1 11.7 16.7 2.8 7.9

Endoc/ad/a mwicma - 2.8 5.0 13.9 15.0 4.4 6.9

I Enteromorpha I/nza 23.9 - - 4.0 Petroce//s sp(p). 0.6 0.6 5.6 0.6 7.2 7.8 3.7

Bossiellaplumosa 2.8 3.9 2.8 2.8 7.2 3.3

Polysiphoniahendryi 1.1 13.3 3.3 1.1 1.1 3.3

I AU/va nalipusjaponicus sp(p). 17.2 1.7 0.6 28 1.7 - 9.4 0.6 1.7 2.9 3.1

Mastocwpux pap///ams 0.6 0.6 7.2 5.0 1.7 2.5

Crustosecorallines, unident. 1.7 3.9 2.8 2.8 1.9

I Ir/daea Enterm_xp/endens rpha sp(p). -1.1 0.6 3-.9 2.8 3.3 4.1.41 1.7 1.8 1.4

Porphyra _p). 7.8 - 1.3

i Chrysophyta,unidem. 3.9 3,3 - 1.2

Comllina vancouceriensis 1.1 2.2 2.2 1.7 1.2

¢Montha//a_a - 2.2 I. 1 0.6 0.6 0.6 0.9

Petaloniafascia 1.1 1.1 1.1 1.1 0.7

I CIadophoraco/umb/a_ 0.6 1.7 1.1 0.6

Red crusts 1.1 0.6 0.6 1.1 0.6

Microcladia borea//s - 1.l - 0.6 0.3

BrownCrusts - - 1.1 0.2

I Iridaea Odon/ha//a heterocw waxh/ngton/ens/s 'pa 0.6 0.6 0.6 0.2.

Cora///na offic/na_ - 0.6 - - 0.1

i Fucus gardner/ - 0.6 - 0.1

GATGOR 0.6 - - 0.I

Ha/oxaccionmner/canum 0.6 0.1

Iridaea sp(p). 0.6 0.I

I Neor/wdomehz/at/x - 0.6 0.1 Phaeostroph/on/rregu/are - - 0.6 0.1

P/ocam/um v/o/aceum - - 0.6 0.1

Pteros/phon/a pennata 0.6 - 0.1

I TotalMacrophyteCover 56.2 37.5 59.2 63.1 56.2 31.9

_ratu -Cever(Pereeet)

I Ozthama/ux sp(p). 3.3 9.4 13.9 - 2.2 13.9 7.1

Myt//ua ca//forn/anus - 0.6 1.7 4.4 5.6 27.8 6.7

I Ba/anus g/andu/a 1.7 7.8 7.2 1.7 16.7 6.0 Lottia digitalis 0.6 2.8 0.6 0.6 2.2 2.2 1.5

"Co///se//a"sc_ra - 1.1 2.2 0.6

paradig/ta//s - 2.2 0.6 - 0.5

I Nuce//a PoUicipesemarg/nata polymeras 0.6- 0.6 0.6 1-.7 - 0.6 0.4 0.3

Strongylocentropurpura ms ms - 0.6 - i.1 0.3

Tec_tra scu_m 0.6 1.1 - 0.3

I Anthopleura elegantissima - - 0.6 0.6 0.2

115

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I

Table A-I1. Macrophyte, macroinvertebrate, and substratum abundances in the My6/us assemblage spring-cleared plots •

at Sea Ranch for fall sampling periods from 1985to19922 (continued)

Overall i

Taxon/Substratum 1985 1986 1987 1988 1989 1992 Mean 1

Mnv_ - _ver (Percent) •

II I

L/got/ha $ctaalaga/p/ena 0.6 - 0.6 0.2 i

Nuttal//na cal_'ortfica 0.6 0.6 0.2

Phragmatopoma caSforn/ca - - 1.1 02 •

Amph/poda, un/_nt. 0.6 - 0.1

LmI/a pe/ta - 0.6 O.1

Lotfia sp(p). - 0.6 - O.1

NuceUa laraellosa 0.6 0.1 •

Pagurus sp(p). - 0.6 0.1

Pisaster ochraceus - - 0.6 0.1

Porifera, unldent. - - 0.6 0.1 I

Sem/balanus car/osuz - 0.6 - 0.1 B

Total Macro_nveaebr_e Cover 8.0 16.8 25.8 17.9 18.5 63.0

Ill

_rates - Density (No.10.1875 _ i

Lo_a sp(p). 27.1 172.9 189.6 70.8 56.3 389.6 151.1

digitalis 25.6 112.4 85.7 39.3 26.8 15.8 50.9 l

"CoLlisella" scabra 16.3 16.0 33.1 73.2 91.0 33.2 43.8 U

Littorina sc_mdata/plena 7.5 47.7 24.5 18.5 9.8 86.0 32.3

_ 30.8 0.7 18.3 40.5 3.7 2.7 16.1 I

L_ para_g_/s 0.7 17.3 1.7 15.6 17.7 4.8 9. 6 •

Nucella emarginata 3.1 5.3 5.3 2.3 0.7 5.7 3.7 I

Tectura scumm 4.0 0.3 0.3 2.7 1.3 1.4

Lepm_er_ sp(p). - 0.3 4.0 1.7 1.0 •

cal/formca 1.0 0.3 - 1.0 1.7 1.3 0.9 1

Total Nmmbcr of Mag_e Tm 8 16 18 18 15

1

Total Number of Macreiuvertebrate Tm 16 12 16 19 18 17 1

T_ Nmaber of All Tan _ _ M _ _ 32

Substrata-_ _-cmt)

Bare rock 42.2 53.3 30.6 41.1 42.8 19.4 38.2 i

Rock 26.1 8.3 6.7 13.9 9.4 6.1 11.8

Shell debrm 2.2 0.6 1.7 2.8 1.I 1.7 1.7 I

Sand 1.7 - 0.6 - 0.4

I

ca_g_ are _ _ _ ove_ means, _n 1i¢_ __y ff _ ove_ means are_. ToM _ cover cane_ 1_

_ _ _ _ye_ _ sampled. A dash(-) indicates Riletaxon/substratumwas no( recorded duri_ that_all_ing period. •

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116 I
I Table A-12. Macrophyte, cleared plots atmacro Sea/Ranch nvertebrate, duringandspring substratum 1991.1 abundances in the Myt//us assemblage

i Spring-Cleared Fail-Cleared

Taxon/Substratum Mean S.D.2 Mean S.D.

I Macrephytes - Cover (Percent)

RalD_ sp(p). 8.3 5.8 3.9 5.4

I Ana//pus Endoc/ad/japon/cus a tour/cam 52.6.2 38.2.9 272..82 231.9.7

Bossiella plumosa 2.2 2.6 8.3 13.0

i Petrocelis sp(p). 2.2 3.9 6.1 4.2 lr/daea sp/endens 1.1 1.0 2.2 2.6

Chrysophyta, unident. 0.6 1.0 -

_ra co/umb/ana 0.6 1.0 1.1 1.0

I MCora///na _ vancouver/ens papi//mus /s 0.6 0.6 11..00 4.41.1 21.6.0

Crustosecorallines,unident. 0.6 1.0

I _Gelid ia ium coulteri difformis 00..66 1. 1.00

Polysiptumia hendryi 1.7 2.9

I Total Cover 24.0 60.6

Macrophytc

Maeroinvertebrates - Cover (Pereeat)

I M)¢i_ californianus 21.7 3.3 6.1 6.7

Ba/anus g/andu/a 10.6 9.2 14.4 12.6

i OCJmma/ussp(p). 6.7 1.7 3.9 5.4 "ColliseUa"scabm 3.3 3.3 3.9 1.9

Po///c/pes po/ymerus 2.2 3.9 2.2 1.0

Lou/a d/g/ta//s 0.6 1.0 -

I Anthopleura elegantissima 0.6 1.0 Haliclonapermol_ 0.6 1.0

/aTtt/aparad/g/ta//s 2.2 2.6

I Phrag Tegulanufunebrali _o/wma_ca//forn_ 10.6.1 1. 1.90

i Total MactoinvertebrateCover 45. I 35.6

Maerelavertebrates - l)easity (N0.10.1875 m2)

I "Collisella"acabm 178.8 106.0 100.4 45.2 Lon/a d/g/ta//s 14.6 6.2 14.3 13.1

Lott/a sp(p). 14.6 13.0 45.8 68.8

I Lottiaparadig Littorina scumitalis lta/plena 42.3. I 53.69 7-.7 4.7

Tegulafunebralis 2.0 2.0 0.3 0.6

i Lott/a pe/ta 1.7 1.5 2.3 2.3

117

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Table A-12. Macrophyte, macroinvertebrate, and substratum abundances in the Mytilus assemblage I !

cleared plots at Sea Ranch during spring 1991oI (continued)

Taxon Spring-Cleared Fall-Cleared I/Substratum Mean S.D. 2 Mean S.D.

Macroinvertebrates - Density (No.I0.1875 m2) I

Nutta///na ca/gorn/ca 1.7 1.5 1.7 1.2

Nucella emarg/nata 1.3 1.5 - I Strongylocentrotus purpuratus 0.3 0.6 -

Mopalia muscosa 0.7 1.2

Total Nmber of Macrophyte Tan 10 13 I

Total Number of Macroinvertebrate Taxa 14 15

Total Number of All Tm 24 28 I

Substrata - Cover (Percent) I

Bare Rock 36.1 5.9 22.8 9.5

Rock 8.3 7.6 19.4 11.1 I

Shell Debris 1.7 2.9 -

nJmDataar lmdaccordi ef'm_mKina tothene_licI ans.aborat inthe ttpr efieInc. isng, -(199 cl_-e2dpt). oDalaar ts,thenelist meeamdalpl offlxr mbeeeticaIly ploffts(n= thet30).eaTaxaand mareequal. _suatawilhin Totalperceeachcat ntcoverecan goryare I

exceed100percent_ mmlti_ layersweresampled.A dash(-)haficatesthe taxon/_ wasnatreeordedin theplots

indicated.

2 S.D. ffi StandardDeviation I

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I Table A-I3. Macr cleareephyt d plots e, macroinv at Sea Ranch ertchrat forefall , andsampling substratumperiods abundanc from 198 esin6 tothe1992.' Myt//us assemblage fallOverall

I Taxon/Substratum 1986 1987 1988 1989 1992 Mean

i Mj_'ophyl_ - Cover(Percent) Endodad/a mur/cata - 2.2 19.4 20.6 18.9 12.2

Mastocarpuspapillmus 2.2 7.8 12.2 8.9 3.3 6.9

I lridaea splendens 10.6 4.4 3.9 7.8 5.0 6.3

Fucus gardneri - 0,6 0.6 0.2

Ra/fs/a sp(p). 10.0 6.1 0.6 2.2 3.8

Petrocelis sp(p). - 3.9 3.9 6.1 0.6 2.9

I Polysiphonia C/adophora co/mnb/ana hendryi 0.6 - 4.- 4 0.6 2.8 I0,0 6.1 2. 2.81

Petaloniafascia 7.8 1.I 1.1 2.0

Boss/e//a p/umosa 1.7 0.6 3.9 1.2

I ACora///na na//pusjapon/o mnamzvesr/ens/s 1.7 0.6 2.2- 1. 3.31 1.7 1.1 1.0

Odontha_flaccosa - - 0.6 3.9 0.9

I Iridaea/teteraca_ 3.3 0.6 0.8 En:ero,nor_spO). 0.6 1.7 - 0.5

Brown crusts - - 2.2 0.4

Crustose corallines,unident. 0.6 0.6 0.6 0.4

I Por R phyra ianceolata 1.7 - - - 0.3

ed crusts - - 1.7 0.3

Scytos/phon/omentar/a 1.7 - - 0.3

Bossiella sp(p). - - 1.1 0.2

l PolysO_toManathaniellii - 1.1 - 0.2 Vlva sp(p). 0.6 0.6 0.2

Halosaccion americanum - - 0.6 - O.1

i _a_eaad_,rm/s . - 0.6 0.1

Microcladia borealis - 0,6 0.1

Pel_fia-Pelveaopsb sp(p). - 0.6 O.1

Red blades - 0.6 O.1

l TmalMacrophyteCover 35.2 34.0 54.1 57.0 59.0

Macrehtver_rat_-Cover(Percent)

I Chthama/us sp(p). 6.1 13.9 26.1 12.2 7.8 13.2

Ba/anus g/andu/a 5.6 12.8 6.1 6.1 6.7 7.5

Myt//us ca//forn/anus - 1.7 8.9 2.1

I "Collisella'soabra 0.6 1.1 2.2 1.1 0.6 1.1

Loft/a d/g/ta//s 1.1 2.2 - 1.7 1.0

PoUicipespolymerus 0.6 1.1 1.7 1.7 1.0

Littorina scumlma/plena - 1.7 0.6 0.5

Phragnmtoponmca//forn/ca - 0.6 1.I - 0.3

Lat/a parad/g/za//s - O.6 0.6 - 0.2

Lot't/ape/ta 0.6 0.6 0.2

Nutta///na Lau/a//mamca//fom /a ica -- - 0.6 0.6 0.6 0. 0.12

Polycbaeta, unidem. - 0.6 0.1

re_af_w.b_is - 0.6 o.i

Tetraclita rubescens - - 0.6 0.1

119

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Table A-13. Macrophyte, nnutcroinvertebrate,and substratum abundancesin the Myt//us assemblage fall- n

cleared plots at Sea Ranch for fall sampling periods from 1986 to 1992.I (continued)

Overall l

Tax_t_m 1_ In 1_ 1_9 1_ Mean

Macroinvertebrates - Cover (Percent) I

Total _cromve_ra_ Cover 14.0 28.4 41.8 25.7 29.8

Macroinvertebrates - Density (No.I0.1875 n_ l

_). 130.8 41.7 39.6 52.1 100.0 70.8 B

"Collisella"scabra 100.5 55.7 68.1 78.8 10.3 62.7 I Loff/a d/g/ta//s 31.1 44.5 52.5 18.2 27.5 34.8

Littorina scutulata/plena 9.8 13.4 66.5 30.0 23.2 28.6

Lottia paradigitalis 17.3 8.7 12.5 9.1 4.1 10.3 •

Lott/a pe/ta 4.3 19.0 1.0 7.3 16.2 9.6 I

Nucella emarginata 2.0 2.3 6.3 2.7 3.0 3.3

NuUa///naca_foru_ 0.3 0.7 2.0 0.6

Ocenebra circumtexta - 1.0 2.1 - 0.6 •

Lott_ _umda 1.0 1.0 0.3 0.5

_rongy/ocemrmus purpuratus - - 0.3 0.1

Tegulafunebralis - 0.3 1.0 - 1.3 0.5 I

Leptaster/as sp(p). - 0.3 0.3 0.3 0.2 •

Lepidochitona dentiens 0.3 - 0.1

Loff_ asnff - 0.3 0.1

Neme_, m_. - - 0.3 0.1 1

Total Numbe_ of Macrophyte Ta_m 8 12 15 16 13

Total Number of _rate Taxa 12 12 15 16 18 1

Total Number of All Tan _ _ _ 32 31

_rm - _ _n_mt) 1

1

_e _ 56.7 42.2 25.0 32.2 _.4 36.1

Rock 19.4 10.6 '7_.8 18.3 25.6 19.3 I

S_il debris - 1.1 2.2 5.0 3.9 2.4 •

Sand - 0.6 0.1

1986-1989dataarefromKinnelicLal_nttofies.Inc.(1992). Dalaaremeansofthreepiols(n=3).Taxaandsubsw_within l

!

eachcategoryarenmk_ acce_n8 tooverallmeans,thenlisted__y if theoven_ meansareeq_. T_d percentcever 1

canexceed1_ _rcent becausen_fip_ layerswereum_. A dash(-)_ themxo_su_uammwasnotw,ce_ dur_

tha_t _ri_. me

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I

120 I
I Table A-14. Macrophyte, the Endodadia/Masto maeroinvertebrate, carpus assemblage and substratum control plots abundances at Sea in

Ranch during spring 1991.1

I Standard Taxon/Substratum Mean Deviation

I Macrophytes - Cover (Percent)

I Endocladia Pelvetia-Pelvetiopsis muricata sp(p). 418.9 6.7 30.6 31 3

C/¢g/cgthoraco/umb/ana 17.8 16.7

i Petroce//s Mastocar sp(p). 15.0 18.8 puspapillatus 10.0 5.0

Cryptosiphonia woodii 5.0 7.3

Fucus gardneri 5.0 8.7

I Ra/ anaUp/s _/a sp(p). 1.7 1.7 japonicas 1.I 1.9

Corallina vancouveriensis 1.1 1.9

I Mas Neot_ jardinii 1.1 1.0 rhodomela larix 1.I 1.9

P/ocam/um v/o/aceum 1.1 1.9

U/va sp(p). 1.1 1.9

I Callithamion 0.6 1.0

p/keanum

Ir/daea sp/endens 0.6 1.0

m TotalMacrophyteCover 127.9

Maerolnvertebrates - Cover (Percent)

I Anthopleura elegantissima 5.0 8.7

Ouhama_ sp(p). 2.8 3.5

Ba/anus g/andu/a 2.2 3.9

I "Collisella"scabra 0.6 1.0 Tegtdafunebra//s 0.6 1.0

I TotalMacroinvertebrateCover 11.2

Maereinvertebrates - Deasay (No./0.1875 m2)

I _ _(p). 49.6 19.1

"Co///se//a"_cabra 22.1 19.9

Lott/a d/g/taRs 3.7 3.5

I Tegulafunebralis 3.7 5.5 Lottiapelta 1.0 1.7

L/uor/na scutu/ata/p/ena 0.3 0.6

I NuceUaemarginam 0.3 0.6

I

121

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I

Table A-14. Macrophyte, mcroinvertebrate, and substratum abundances in

the RanchEndocladia/Mastoca during spring 1991. rpusxassemblag (continued) e control plots at Sea I

Standard

Taxon/Substratum Mean Deviation I

Total Number of Macrophyte Taxa 16 I

Total Number of Macroinvertebrate Taxa 10

Total Number of All Taxa 26 I

Substrata - Cover (Percent) I Rock 30.6 17.5

Barerock 7.8 7.5

I

Dmare fromKi.mmelicLaboramries, Inc. (l_J2). Dataare means of threeplots(n=3). Taxaand

subsuatawithineach catego_ are rankedaccord_ to the means,thenlisted alphabeticallyifthe

means are equal. Totalpercentcover can exceed 100percent becausemultiplelayers were sampled. I

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122 I

I
IIIIIIIIIIII

a

IIIIII
I Table A-16. Macrophyte plots at Pescadero , macroinv Rocks ertebrate for fall , sampling and substratum periods abundances from 1985 toin 1992 the Myt//us : assemblage control

Overall Taxon/Substratum 1985 1986 1987 1988 1989 1992 Mean

I Macrophytes- Cover(Percent)

Bossiella plumosa 13.3 10.0 6.1 9.4 3.9 - 7.2

I CPetrusto rocelis se corall sp(p).ines, unident. 139.4.3 4. 1.74 3.9 6.1 1-.1 1.7 51.9.1

Endocladia muricata 2.2 2.2 0.6 4.4 0.6 0.6 1.8

i Ana//pus japon/cus 3.9 4.4 1.7 - - 1.7 Cladophora columbiana 4.4 0.6 2.2 - 1.2

U/va sp(p). 4.4 1.1 I. 1 0.6 - 1.2

Cora///na vancouver/ens/s 6.7 - - 1.1

I GATGOR Red crusts 3.- 3 0.6 3.- 9 - 2.8- 0.7 1.1

Ir/daea sp/endens - 0.6 1.7 0.6 0.5

I Por Corphyr allinaa per officinal foratais -

- 0.1.67 0.6 1-.7 0.- 6 -- 0. 0.45

Mastcwnrpuspapi//ams 1.7 - 0.3

Pelvetia-Pelvetiospsp(isp). - I.7 - 0.3

I Binghanfwpsi_ caespitosa - 1.1 - - - 0.2 Cy//ndrocarpus rugosus - 1.1 - - 0.2

Polysiphonia hendryi 0.6 0.6 - 0.2

I RaZ Red blades _/asp(p). 0. 0.66 .... - - oO..11

II Total Macrophyte Cover 64.4 27.9 16.2 30.6 7.9 5.7

Maeroiavertebrates - Cover (Percem)

I Mytilus californianus 30.0 52.8 70.0 65.0 86. I 80.6 64.1 Ba/anus g/andu/a 6.1 11.1 11.1 13.3 11.1 16.7 11.6

PoUic_espolymeras 4.4 10.0 I5.6 14.4 11.7 6.1 10.4

I Tetracliz ¢3_thama/urubescens .¢sp(p). 10.6 50 10.6 39 6. 3 3I 9.4 22 8.3 06 164.4.1 10.2 3

"CoUisella" scabra 3,9 0.6 3.3 3.3 1.1 2,0

i Nuttallina californica 2.2 0.6 1.7 0.6 - 0.9 Lott/a d/g/ta//s 1.7 0.6 1.1 - - 0,6

Lott/a pe/ta - 1.1 - 1.1 0.4

Haliclona sp(p). 1.1 - 0.2

I Lott/a//matu/a 0.6 - 0.6 - - 0.2 Halichondria panicea 0.6 .... 0.1

Leptasterias sp(p ). - 0.6 - 0.1

I Lon/a Myt//usg/geduantea//s -- 0-.6 0.6 -- -- 0O..11

i Total Macroinvertvbrate Cover 66.2 90.2 106.7 112.7 122.3 126.1

125

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Table A-16. Macrophyte, macroinvertebrate, and substratum abundances in the MytUus assemblage control i

plots at Pest_dero Rocks for fall sampling periods from 1985 to 1992: (continued)

Taxon Overall I/Substratum 1985 1986 1987 1988 1989 1992 Mean

Macroinv_ebra_ - Dem_ _o./0.1875 m2) R

"Collisella" scabra 71.4 42.1 42.3 1_.4 85.7 33.3 63.1

Lottia digitalis 5.4 42.3 31.1 69.6 9.0 9.8 31.2 i

Lm_ _). 18.8 12.5 41.7 8.3 2.I 13.9

Nuttallina californica 24.0 11.7 7.7 14.7 8.7 2.0 11.5

Lottia limatula 3.3 2.7 3.3 5.3 36.0 12.3 10.5 •

Littorina scutulata/plena 6.9 0.3 6.6 I0.8 19.1 7.3 I

Lott/a pe/ta 7.5 4.3 6.0 2.0 1.3 8.4 4.9

Lottia paradigitalis 1.0 - 15.0 1.0 1.7 1.3 3.3 I

Lott/a g/gantea 0.3 0.7 0.3 0.3 0.3 •

Leptasterias sp(p). - 0.3 - 0.7 0.2 l

NuceUa emarginffta - 1.0 0.3 - 0.2

LepMoch/tonadent/ens - - 0.3 O.1 i

Tegula brunnea - 0,3 - - 0,1

Total Nmber of Macrophyte Taxa 13 11 8 9 5 4 l

Total Number of Macroinvertebrate Tan 16 14 15 15 15 13

Total Number of All Tram _ 25 _ _ _ 17 i

1

Bare rock 6.7 4.4 0.6 0.6 0.6 - 2.2 1

Rock 6.1 - 1.7 0.6 3.3 2.0

S_Ii _b_ - 0.6 1.1 - 1.1 - 0.5 1

I

i l_-l_arefi, omKnm_L_ommms, lne (1_). D_are_of_'rlm_o_(n--3). Taxa_ndm_mw_n_h

cam_ are _ acco_ m ove_ meatus. _e_ fi_ _ _ _ eve_ means are _. Tm_ _ cover can e_ 1_ •

_rcent _cau_ m_ _rs were_m_. A,_h (-) __ _u_mm wasnotreco_ _ thJtmm_ _.

II

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126 I
I Table A-17. tMacrophyte, he Mytilus assemblag macroinveertebrate control plots , andatsubPescadero stratum abRocks undanc dureins gin

spring 1991.1

Taxon/Substratum Mean Deviation

I Maccophytes - Cover (Percent)

Endocladi Porphyraalanmuceolata ricata 43..43 75..87

Porphyraperforata 2.2 3.9

Cora///na _mco_er/ens/s I. 1 1.9 Ana//pusjapon/cus 0.6 1.0

BossieUaplumasa 0.6 1.0

U/_ sp(p). 0.6 1.0

I Tota_MacrophyteCover 12.8

I Maeroinvertebrates - Cover (Pereent)

Mytilus califomianus 90.6 5.1

Ba/anus g/andu/a 18.9 8.2

I Tetraclita rubercens 9.4 2.6 Pollicip_ polymevus 5.6 1.9

Chthanm/ussp(p). 2.2 3.9

I Lonia "Collisella" digitalisscabra 1.7 1.7 0.01.7

Antlwpleura elegantissima 0.6 1.0

I Pachygrapsus crassipes 0.6 1.0

Total MacroinvertebrateCover 131.3

I Maerolavertebrates - Density (No.10.1875 m2)

"Collisella"$cabra 48.1 25.0

I Lott/a Lm_ padib6t rad/g/ta//s a//s 4113.7.8 1229..86

//matu/a 9.1 6.7

i Lott/a sl_p)• 4.2 3.6 L/ttodna scuadata/p/ena 1.7 1.5

Nuttallina californica 1.3 2.3

Lou/a pe/ta 1.0 1.0

I IMopa//a onia gigantea 0.3 0.6 muscosa 0.3 0.6

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127

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Table A-17. Macrophyte, macroinvertebrate, and substratum abundances in I

the MytUus assemblage control plots at Pescadero Rocks during

spring 1991: (continued)

Standard I

Taxon/Substratum Mean Deviation

Total Nmnber of Macrophyte Tan 7 I

Total Number of Macroinvertebrate Tan 17 I

Total Number of An Taxa 24

Substrata - Cover (Percent) I

Rock 0.6 1.0

Shell debris 0.6 1.0 I

n Dataare from K_nnwJ_Laboratories,Inc. (1992). Dataare nga_ of three plots(nffi3). Taxaand I

substrata withineachcategoryarerankedaccordintgofigmeans, thenlisted alphalglicaliy ff the

means are equal. Totalpercent cover can exceed 100 percentbecause mullip_elayers were sampled.

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128 I

I
I Table A-18. Macrophyte, macroinvertebrate,and _ abundances in the M_/Jus assemblage spring-cleared plots

at P,_mdero Rocks for fall sampling periodsfrom 1_ to 1992._

Overall

I TaxonlSub_ratmn 1985 1986 1987 1988 1989 1992 Mean

i MBossie acrUephyt aplumosa e-sCover(Pemmt) - 23.3 58.3 35.0 42.2 27.8 31.1

Ir/daea sp/endens 1.1 36.1 47.8 37.8 12.2 1.1 22.7

I Ulva sp(p). 85.0 3.9 20.6 15.6 4.4 21.7 Crustosecorallines,unident. 0.6 30.0 12.8 8.3 10.0 6.1 11.3

Cora///na vancouver/ens/s 0.6 6.7 21.7 10.6 1.7 6.9

Ana/_us japon/cus - 8.3 1.1 8.9 7.8 6.1 5.4

I Oadophora GATGOR co/umb/ana 6.7- 55.

.66 0.6 6. 0.76 7.8 3.3 30..96 42.

.09

Poly$iphoMahendryi - 1.1 7.2 6.1 2.2 2.8

Egregia menziesii - 1.1 10.6 4.4 2.7

I OCora///na y//ndrocarpus o_c/na//s rugosus -- 0. 6.76 1.7 3.3 7.2 11.7.6

Mastcmarp_papillams - 0.6 1.1 2.2 0.6 0.8

I Rhodog/ossm'naffine - 2.8 1.1 - 0.7

Onysophyta, ,nideat. 2.8 - - 0.5

P/ocam/um v/o/aceam - 0.6 1.1 - 1.1 0.5

Redfi/aments - 2.8 - 0.5

I Binghamiopsis Mastoa cae_tosa - 0.6 1.1 0.6 0.4 u'pusjardinii - 2.2 - 0.4

Petvetia-Pelvetiopsis sp(p). - - 0.6 1.7 0.4

Pr/oMt/s/anceo/ata - I. 1 0.6 0.3

I R_m Cladophora s_).xtimpsonii 0-.6 01..16 0.6 00..32

Petaloniafascia 1.1 0.2

i Petroce//s sp(p). 0.6 0.6 0.2

Red cr'asts - 1.1 - 0.2

$cytos/phon/¢mtemar/a 0.6 0.6 - - 0.2

Brownblades 0.6 - 0.1

I Outetomorp_//hUm - 0.6 0.1 Co/poatenias/nuosa 0.6 - 0.1

_ l_za 0.6 o.1

Ir/daea hete_ - 0.6 - 0.1

I MPorp/croc/a _yra_sp(p). borea//s 0.6- 0-.6 - 0. O.11

Red blades 0.6 - 0.1

I Total _yte Cover 102.7 124.6 178.2 153.5 107.2 58.5

_rates - _ (Peremt)

i Myt//us ca//forn/an_ - 3.3 8.9 15.6 20.6 36.1 14.1

Ba/anus g/andu/a 2.2 3.3 1.7 3.3 15.0 4.3

Tetrac//m rubesc_s - 0.6 3.3 6.1 1.7

I _Ou/uvna/usa_spfot(p). n/m 0.6 0.I.61 1.7 1-.7 32.8.3 10.7.3

"CoUisella"so_bm 1.7 0.6 1.1 - 0.6

Lott/d/g/t a a//s 1.7 0.6 0.6 - 0.5

I Porifera,unident. - 1.7 0.6 0.4

129

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1

Table A-18. Macrophyte, mcroinvertebrate, and substratum abtmdancesin the My_ assemblage spring-cleared plots •

at Pescadero Rocks for fall sampling periods from 1_ to 1992.I (continued) 1

Overall I

Taxon/Substratmn 1985 1986 1987 1988 1989 1992 Mean

Macroinvertebrates - Cover _rcent) l

Lott/a pe/ta 0.6 1.1 0.3

Pollicipes polymerus 0.6 0.6 0.6 0.3

Haliclona permo///s - 1.1 - 0.2 1

Sem/ba/a_ car/osus 0.6 - 0.1

Total MacroinvenebrateCover 4.5 11.2 11.2 20.2 34 64.5

Macroinvertebrates - ]Density(No.10.1875 m_) l

"Coilisella"scabra 24.1 76.8 2.0 16.8 78.2 41.8 40.0 I

sp(p). 12.5 37.5 20.8 81.3 29.2 12.5 32.3 I Loffia digitalis 8.6 37.3 8.0 8.5 14.0 2.7 13.2

NunMlina californica 2.7 5.0 1.7 4.3 35.9 28.7 13.1

l._orina sc_ulata/plena 27,1 1.0 - 47.9 12.7 •

Lottia paradigitalis 6.0 1.3 9.9 7.3 3.0 4.6 I

Lot_ pe/m 2.3 ii.I 3.0 4.0 1.3 5.1 4.5

Lm_ _ 0.3 0.3 0.3 0.3 4.0 8.5 2.3

Tomce//a_ 2.I 0.4 •

i

Loffia gigantea 1.0 - 0.3 0,3 0.3

Lep_ hartwe&ffi 1.0 - - 0.2

Fissm'e//a vo/ca_ - - 0.3 - 0.3 0. I I

o.7 o.1 •

Stron89,tocentro pwpuratua ms 0.7 0,1

am

Tegula brunnea 0.3 O.1

Total Number of Maerophyte Tm 15 14 19 18 13 12 I

Total Number d Macrelavertebrate Tan 8 14 13 12 13 16

1

Total Nmmberof AH Taxa 23 28 32 30 26 28 I

Sulm_ - Cover¢Per_)

Rock 27.8 6.1 3.9 4.4 3.9 6.1 8.7 l

Bare rock 7,2 8.9 3.9 2.8 2.8 4.3

Shelldebris - 1.1 0.6 0.3 l

1

' 1985-1989dalaarefromKiaae_ L.ll_ratories,Inc.(1992). Dataaremeusoftl_ pi_ (n=3). Tm and_bstratawithinea_h

[_ _ [ _ m _[ _, in _ __ ff _ [e_ [ _ _l Total percent covercanexceedI00 1

gew.entbecausemel_:_elayersweremm_ed. A dash(-)indicatesthetaxon/_ wasnotrecordedduringthatsamplingperiod, I

I

130 I
I Table A-19. Macrophyte, cleared plots atmacrolnvertebr Pescadero Rocks ate, during and substratum spring 1991. abundances _ in the Myff/us assemblage

I Spring-Cleared F_l_u_d

Taxon/Substratum Mean S.D.Z Mean S.D.

Maerophytes - Cover (Percent)

BossieIlaplumosa 33.9 17.5 40.6 26.9

I Ana//pus lridaea splendens japon/cus 111. 0.0I 68.8.3 58..09 10.2 1.7

Crustosecorallin_, unident. 7.8 9.5 7.8 4.2

i Mast Corallina vancouveriensis 6.7 1.7 14.4 12.5 ocarpusjardinii 3.3 1.7 3.9 5.4

C/adophora co/umb/ana 2.8 3.5 4.4 7.7

Ra/f_ sp(p). 2.2 3.9 0.6 1.0

I P/ocam/wn v/o/aceum 1.I 1.9 0.6 1.0 Binghamiopsis caespitosa 0.6 1.0 -

Mastoo2rp_papiUatus 0.6 1.0 7.8 13.5

I Pol Porphysiphonia ym lanceoiata hendryi 00..66 1.0 1.0 0.6 1.0

_va _p). 0.6 1.0 2.2 2.6

i 1 GATGOR 5.6 9.6

I Egregia menziesii 5.0 8.7

Ir/daea sp(p). - 3.3 5.8

Endoc/ad/a mur/cata 1.1 1.9

I PetroceIis Redcrustssp(p). 11.1.1 11..99

Ca///arthron tubercu_um 0.6 1.0

I Emeromorpha G/gart/na cwm_//cu/ata -- 00.6.6 1.0 1.0

Greenfilaments 0.6 1.0

Po_hyraperforata 0.6 1.0 Total_ C_ 81.9 117.0

Maerelavertebrates - Cover _)

Myt//us ca//forn/anus 30.0 18.0 10.6 7.9

Ba/an_ g/andu/a 12.2 6.7 2.8 2.6

Tetradita rubescens 7.2 5.4 3.3 2.9

Nutta///na ca//forn/ca 2.2 1.9 3.3 1.7

Ouhanm/us sp(p). 1.7 1.7 0.6 1.0

Loa_a_s 1.7 1.7 1.1 1.9 Ha//c/onapermo//Lv 1.1 1.9

g'rongy/ocemrmus pur/mrmus 1.1 1.9

Lou/a Pollicipes pe/tapolymergs - 0.6 0.6 11.0.0

TotalMacroinvertebrateCover 55.0 25.1

131

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i

1

Table A-19. Macrophyte, macroinvertebrate, and substratum abundances in the Mytilus assemblage •

cleared plots at Pescadero Rocks during spring 1991) (continued)

Taxon Spring-Cleared Fall-Cleared I/Substratum Mean S.D.: Mean S.D.

Macroinvertebrates - Density (No.t0.1875 m") 1

Lotlia digitalis 73.4 71.8 31.9 28.4

"CoUiseUa"scabm 72.3 44.7 16.4 27.6 1

Lott/a para_gita_s 27.8 48.2 12.0 19.9

Lott/a sp(p). 25.0 27.2 12.5 16.5

Nuttallina californica 23.1 6.2 19.7 13.1 •

L/trOt/ha $cutu/ata_/ena 10.4 18.0 1

Lot//a//matu/a 2.8 4.8

Lo_a asnff 0.7 1.2 I

Leptasterias sp(p). 0.3 0.6 l

Lottia pelta 0.3 0.6 6.5 11.3 1

Strongylocentrotus purpuratus 2.7 4.6

Fissurella volcano 0.7 0.6 •

Tegula puUigo 0.3 0.6

Tetal Number of Macrophyte Taxa 14 23 1

Total Nmber of Macroinvertebrate Tan 14 15

Total Number of All Taan 28 38 I

Snbstrata - Cover (Percent)

I

Rock 5.0 1.7 4.4 3.5 l

Bare rock 4.4 5.1 4.4 3.8

Shell debris 0.6 1.o 11

Dataare f'mmKinm_ Laboratories,Inc.(t992). Dalaaremeamofthreeplols(n,=3).Taxaandsubsuautwithineachcategoryarc

rankedacconflin8tothemeansin thespri_-clea_dplots,thenlistedalptmbedcallyffthemeansareequal. Totalpercentcovercan •

exceed100penamtbecausemudt_elayersweresampled.A dash(-) badicatesthetaxo_subswalumwasnotrecordedin theplots I bs_cated.

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132 I
I Table A-20. Macrophyt cleared plotse, macroinvert at PescaderoeRbrat eckse, and for fall substratum samplingabundances periods fromin th198e 6Myt//us to 1992. assI emblage fallOverall

I Taxun/Snbstratum 1986 1987 1988 1989 1992 Mean

i Macrophytes - Cover (Percent) BossieUaplumosa 5.6 61.7 46.1 25.6 30.6 33.9

lridaea splendens 13.3 42.2 37.8 17.8 3.3 22.9

I Egregia menziesii 43.9 18.3 13.3 20.6 0.6 19.3

U/va sp(p). 36.1 16.7 I6.1 6.7 7.8 16.7

Cnistose corallines, unident. 28.9 7.2 16.1 13.3 8.9 14.9

Cladophora columbiana 5.0 3.9 17.2 13.3 2.2 8.3

Ana//pus Cora///najapon/cus vancouver/ens£v 6-.1 40.

.46 102.8.0 113.9 1.7 62..72 73..89

Corallinaofficinalis - 1.1 - 1.1 11.7 2.8

Potysiphonia hendryi 7.8 2.8 1.1 1.1 2.6

I Mast Rhodog/ossum _ pap///atus affine 3.3 1.7 2.2 0.6 5. 0.66 4.4 1.1 21..45

Otaemmorpha//hum 6.1 1.1 - 1.4

Cy//ndrocarpusrugosus 1.7 1.1 2.2 1.1 - 1.2 Ra/fs/a sp(p). 0.6 0.6 1.7 0.6 2.2 1.1

GATGOR 4.4 0.6 - 1.0

Co/pomen/asp(p). 3.3 - 0.6 0.8

Iri Pelvetia daea heterocw -Pelvetiopsis 'pa sp(p). 3-.3 1.1 0.6 -

- 1.1 0.7 0.6

Petroo_//ssp(p). - 0.6 0.6 0.2

Red crusts 1.I - - 0.2

I Binghamiopsis C.era_um eaton/anum caespitosa 0.6 0.6 - - 0.11

Colpome_ peregrina 0.6 - - 0.1

Endoc/ad/a mur/cata - - - 0.6 0.1 e_aeo_,n i_ 0.6 - - - 0.1

Total MactophyteCover 157.3 175.1 171.7 134.2 85.7

Macreinver_ratu- Cover(Pem_)

Myff/us ca//fonffanus - 0.6 3.3 6.1 17.8 5.6

I Ba/anus Nutta///nag/anca//fornica na -- 1.7 01.7.6 7.2 3.9 1. 1.65

Tetraclita rube$cens - 0.6 1.1 5.6 1.5

"Co///z'e//a"scabra 0.6 1.7 2.2 - 0.9

I PoPorif Uicipes era,unid polyemerus nt. 0.- 6 0.6 0-.6 1.7 - 0. 0.25

Haliclona permollis - 0.6 - 0.1

i Louiad/SitaUs - 0.6 - o.1

r,_ear_ - 0.6 o.1

Lm_ pe/ta - - 0.6 0.1

Strongy/ocenl_ pmpura_ 0.6 - O.1

I Total MacroinvertebrateCover 1.8 0.6 8.5 12.9 37.4

133

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Table A-20. Macropbyte, macroinvertebrate, and substra/um abundances in the My6/us assemblage fall- •

cleared plots at Pescadero Rocks for fall sampling periodsfrom 1986 to 1992.1 (continued)

Overall i

Taxon/Substratum 1986 1987 1988 1989 1992 Mean

Macreinvertebrates - Density (N0./0.1875 m2) i

Lott/a sp(p). 8.3 52.I 1I0.4 8.3 10.4 37.9

"CoUisella"scabra 21.8 4.8 23.2 72.3 18.5 28.1

Nuttallina cal_ornica 3.3 3.7 5.3 15.3 30.0 11.5 1

Lottia digitalis 5.8 6.3 1.3 7.4 19.2 8.0

Lott/a pe/ta 15.3 3.3 5.3 2.0 7.0 6.6

Lottiaparadigitalis 2.8 2.7 10.7 8.0 6.1 6.1 i

Littorina scutulata/plena 2.1 2.1 2.1 1.3 •

_ _m_ 0.3 0.7 1.0 1.0 2.4 1.1 I

Lep/docS/tona dent/ens 1.3 0.3

Leptaster/as _). 1.3 0.3 0.3 •

Tecturas_mm 1.3 0.3 |

D/odora aspera 1.0 - 0.2

Acmaea mitra 0.3 - - O.1

Anisodoris nobilis - 0.3 - 0.1 •

_ep_u_ _ 0.3 0.1 I

Fissurella volcano 0.3 0.1

_ett/a p_:m 0.3 0.1 I

Strongyiocentromspurpuratus 0.3 - - 0.1 •

7egula brunnea 0.3 - O.1

T_ Nmn_ of M_m_ Taxa 16 16 16 16 17 •

T_ N_ _ M_mmv_b_ Tram 15 11 11 14

T_ Nnm_ _ _ Tan 31 27 _ _ _ l

- Caret_t)

Rock 20.6 4.4 8.9 7.8 2.2 8.8 •

Barerock 1.7 5.0 2.2 2.8 7.2 3.8

Shelldebris 0.6 0.6 0.2

Sand - 0.6 - 0.I

I

1956-1969dalaarefrom_Laborawties, lnc.(Ig92). Dalaaremeansofd_-eeplots(n--3). Taxaandsubstralawilkin

ea_categorysre ranked_ Wovendlmeans,thenlisteda]l_abeticaHffthe y overallmeansan_equal.Toudpercentcover 1

canexceed100per_ becausemultiplelayersweresampled.Adash(-)/adicatestheuu_n/submatumwasnotrecordedduring

eatuu_i_ period. I

!

134 I
I Table A-21. Macrophyte, assemblage control macroinvertebrate, plots at Pescadero and substratum Rocks for fall abundance samplings inperiods the Endocladia/Mastocarpus from 1985 to 1992.1

i Overall

Taxon/Substratmn 1985 1986 1987 1988 1989 1992 Mean

I Macrophytes - Cover (Percent)

Endoc/adia mur/cata 69.4 72.8 48.3 55.0 53.9 50.0 58.2

I Mas Pelvetia tocar -Pelvpusetiopsis papiUatus sp(p). 512.8 2.2 347..48 3516.1.0 4141.7.4 29. 15.64 2213..91 3614..25

Crustose coraltines, unident. 28.3 8.9 22.2 3.3 1.7 5.0 11.6

i Rhodoglossumaffme 12.8 13.3 13.3 6.1 6.7 10.0 10.4

Ciadophora columbiana 7.2 10.0 7.8 7.8 4.4 5.0 7.0

U/va s_g_). 5.0 0.6 6.1 8.3 5.0 2.8 4.6

Red crusts 3.3 1.1 3.9 1.1 3.3 2.1

I GATGOR 5.0 3.9 1.7 0.6 1.9 l_/aea sp/endens 0.6 5.6 3.9 1.1 1.9

Gelidium pusillum 0.6 5.6 2.8 1.5

I Otaetomorpha//hum 3.3 - 1.1 - 0.6 0.8

Gelidium coulteri I.I 2.2 - 1.7 0.8

Petrocelis sp(p). 2.2 1.1 1.1 0.7

Ana//pus japon/cus 0.6 I. 1 0.6 0.6 0.6 0.6

I ltmceoltaa 1.1 1.7 0.5 Porphyra

Corallina vancouveriensis 0.6 0.6 - 0.2

Cy//ndrocarpus rugosus 1.1 - 0.2

I Mastocarpus Brown crustsjardinii - 0.6 0.6 00..11

Polysiphonia hendryi 0.6 - - 0.1

Total Macrophyte Cover 197.8 169.0 163.4 148.3 120.7 125.1

Maeruinvertebrates - Cover (Pereem)

,! Ba/atmsg/andu/a 3.3 5.0 0.6 2.2 i.1 1.7 2.3

Mytiluscalifornianus 2.2 0.6 0.6 - i.1 0.8

I /",,Collisella /trot/ha sa" mdat scabraa/p/ena 4.4 0.6 -- 1.7 0.6 00..75

Chthamatusspto). 1.1 - - - 0.2

i l_ottia digitalis 0.6 - - O.1

Total Macroinvertebrate Cover 12.2 5.6 1.2 2.2 3.9 2.3

I Macroinvertabrotes - Density (No./0.1875 m 2)

L/ttor/_ scutu/ata/p/ena 4.5 62.5 52.4 6.6 57.3 103.0 47.7

I Lot "Colli t/a sella sp(p"). scabra 144.4.2 411.3.7 316. 1.38 5618..65 46.8 2.1 1134.

.16 2518.

.15

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Table A-21. Macrophyte, macroinvertebrate, and substratm abundances in the Endocladia/Mastocarpus •

assemblage control plots at Pescadero Rocks for fall sampling periods from 1985to 1992.

(continued)

Taxon/Substratum 1985 1986 1987 1988 1989 1992 Mean

i

Macroinvertebrates - Density (No./0.1875 m2) !

Lottia digitalis 6.8 7.3 2.0 6.8 3.3 3.7 5.0 U

Lottia paradigitalis - 0.3 - 6.2 6.5 - 2.2 II

LaMa pelta 0.7 1.3 5.2 1.3 - 1.4

Nuttallina californica 2.7 0.7 0.7 - 0.7 •

Polyplaeophora,_m. - 4.2 0.7 l

Lepidochitona de,miens - 2.1 - - 0.7 0.3 0.5

LoMa//matu/a 0.7 0.3 0.3 - 0.7 - 0.3

Tegulafunebralis 0.3 - - 0.7 0.2 el

Acanthina sp(p). - - - 0.3 - 0.1

_ce_ __ - - - 0.3 0.1

Te_ brunnea - - - 0.3 - 0.1 I

I

Total Num_ of _#_e Taxa _ 14 16 15 11 12

III

Total Number of Macroinvertebrate Tan 9 11 9 7 13 9 I

Total Number of All Tan 21 25 25 22 24 21

Substrata - Cover 0Pereeat) n

Rock 42.2 22.2 23.9 38.9 19.4 24.4 28.5 •

Barerock 0.6 0.6 2.8 7.8 16.7 10.6 6.5

nell _bm 13.3 0.6 0.6 1.1 - 2.6

!

axe ranked s_.carding _ ovendl mean.% then _ _y ifd_ee o','erlll me.us a.reequal. Total pezcem cover can exceed 100 pete.era

because nmlliple layers were sampled. Adash (-) iadiea_the mxon/tmimmann was not nmolded during that nmplingperiod. !

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136 I
I Table A-22. Macrophyte, the Endodadia/Mo macroinvertebrate _tocarpus asse,mblage andsubstratu controlmplots abundances at in

Pescadero Rocks during spring 1991:

I Standard

Taxon/Substratum Mean Deviation

I Maerophytes - Cover (Percent)

I Endocladia Mustocarpu:muparp///atus icata 6253.09 2318.4.3

Crustosecorallines,unidenL 7.8 8.4

Pelvetia-Pelvetiopsissp(p). 6.7 7.3

Mas_usjardinii 3.9 5.4

Redcrusts 1.1 1.9

¢_adophoraco/utah/aria 1.1 1.0

I Ana Petrocelis sp(p). 1.1 1.0 //pusjapon/cus 0.6 1.0

Ir/daea sp/endens 0.6 1.0

I Total MacrophyteCover 111.8

Maerotnvertebrates - Cover (Percent) Ba/anus g/andu/a 3.9 2.6

Ou_ sp(p). 0.6 X.O

I LiTetraclita ttofina scutulata/ rubescensplena 0.6 11..00

i TotalMacroinvettebrateCover 5.7

Macreinvmebrates - Density (No.10.1875 m2)

I Lo_ ,p(p). 85.4 26.0 /2r/or/ha scutu/ata/p/ena 65.8 114.0

/,tm/a d/g/ta//s 33.3 27.5

L"oa/ Co//a_pare//aad/g/ "scabta/r_a 126.2.7 274..6I

Tegulafunebral_ 0.3 0.6

Lep/doch/tona hanweg// 0.3 0.6

Total Number of Macmphyte Tan 10

Tetal Nmaber of Macroinvertebrate Tan 10

Total Number of All Tan 20

I

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137

!

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!

Table A-22. Macrophyte, macroinvertebrate, and substratum abundances in m the Endocladia/Mastocarpus assemblage control plots at

Pescadero Rocks during spring 1991.1 (continued)

Standard m

Taxon/Substratum Mean Deviation

Substrata - Cover (Percent) m

Rock Bare rock 3315.3.6 176.0.0 m

i Data are from Kinnefic Laboratories, Inc. (1992). Data are means of three plots (n=3). Taxa and m

substrata within each category are ranked according to the means, then listed alphabetically if the

means are equal Total percent cover can exceed 1(30percent because multiple layers were sampled.

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138 m

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i!IIiIIIIIIIIIIIiiI
I Table A-23. Macrophyte, plots at Pointmacroinvertebrate, Sierra Nevada for fall andsampling substratumperiods abundances from 1985 in theto 1992. Mytilus1 assemblage control

I Overall

Taxon/Substratum 1985 1986 1987 1988 1989 1992 Mean

I Maerophytes - Cover (Percent)

BossieUaplumosa 6.1 0.6 2.8 1.1 3.3 11.7 4.3

I Pol Crusto ys_umia secorallin hendres,yiunident. 63.13 3-.3 -1.7 0.6 7.2 6.7 3.3 6. 1.17 3.61

Cora///na vancouver/ens/s 0.6 1.i 0.6 10.0 2.1

i Polys_onia sp(p). 5.0 3.9 - 1.5

Postdsia palmaeformis 2.8 2.8 - 0.9

Rhodoglossum affine 0.6 - 1.1 0.6 1.7 0.7

U_ sp(p). 1.1 2.8 - 0.7

I CySMrocarp_ rugosus 0.6 - 1.1 0.6 1.1 0.6 Petrocelis sp(p). - - 1.7 0.6 0.6 0.5

Oad_hora columbiana 1.7 - 0.3

I Endoc/ad/a P/ocmn/um mu v/o/aceum r/cata 1

-

.1 1-

.7 0.6 -

- 0.0.33

Redcrusts 1.7 - 0.3

GATGOR - 0.6 0.6 0.2

I e._/a spO). - - 0.6 0.6 0.2

And/pus japon/cus 0.6 - - - 0.1

CoraU/nao_c/na//s - - - 0.6 0.I

I Iridaea Microdadia splendens borealis 0.6 -- 0.6 - 00.1.I

Porphyra perforata 0.6 - - 0.1

I Total MacrophyteCover 24.7 17.9 13.4 11.8 16.3 34.7

i Macrotnvertebrates - Cover (Percent) blytilus cdifomianus 81.7 85.0 82.2 93.3 80.6 62.2 80.8

Pollicipes polymeras 8.9 9.4 12.2 6.7 7.8 6.1 8.5

I Lott/a Ba/anud/g/ s g/andu ta//s/a 11.1 1.1 7.2 0.6 2.8 1.1 6.1 1.7 3.3 1.7 3-.3 5. 1.06

"Co///se//a"$cabra - - 0.6 0.6 2.8 - 0.7

i Chthama/assp(p). 1.1 - 0.6 0.6 - 1.1 0.6

/zaz/a pe/ta 0.6 - 0.6 0.6 0.6 0.4

Nuffa///na ca//forn/ca 0.6 - t. t 0.6 0.4

Tetraclita rube_cens - 1.1 0.6 0.6 0.4

I Lottia paradigitalis - 0.6 1.1 0.3 Anthopleura elegantissima - - 0.6 0.6 0.2

Littorina scutulata/pIena 0.6 - - 0.1

I Lot Phratia_ gigantea califomica ---- - 0.6 0.6 0. 0.11

_rongylocentrotus purpurams - - 0.6 0.1

!

139

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!

Table A-23. Macrophyte, macroinvertebrate, and substratum abundances in the Mytilusassemblage control I

plots at Point Sierra Nevada for fall sampling periods from 1985 to 1992.1 (continued)

TaxontSu_Unn 1985 1986 1987 1988 1989 1992 OMveerall an i

[]

Macroinvertebrates - Cover (Percent) •

T_ Macroinve_b_ Cover 105.7 102.2 99.5 111.3 99.I 78.0

Macroinvertebrates - Density (No./0.1875 m 2) I

Lottia digitalis 108.6 73.4 50.7 91.0 56.0 22.8 67.1 •

Lottiapelta 14.3 3.3 42.4 41.2 3.0 24.8 21.5 II

"CoUisella" scabra 1.7 30.4 26.4 37.6 20.6 19.4

Lo_,a sp_p). 10.4 8.3 16.7 25.0 14.6 12.5 14.6 I

Lonia paradigitalis - 2.1 35.1 21.9 9.8 1

Z_uo_a scumhm_na 5.1 4.3 2.1 0.7 2.7 4.8 3.3

Nuua_m _/fo_ca 4.7 1.7 0.3 1.3 1.7 3.0 2.1

Nucella emarginma 3.7 3.7 1.0 - 0.3 0.7 1.6 B

Lott/a//mam/a 4.5 0.3 1.7 1.7 0.3 1.4 []

Tectura scutum 4.5 0.7 0.9

Ocenebra dn_m_a - 2.1 0.3 0.4 []

Strongylocentrotus purpuratus 0.3 0.3 1.3 0.3 II

Tegula funebralis 1.0 - 0.3 0.3 0.3

Lepidochitona dentiens 0.3 - 0.7 - 0.2 m

Linorina keenae - 1.3 0.2 •

Leptasterias sp(p). 0.7 - - O.1

II

Lo_a asnff 0.3 - - 0.1

I

Total Number of Macrophyte Tan 13 8 6 6 8 10 8.$ U

Total Number of Macroinvertebrate Tan 14 11 14 16 16 21 15.3 1

Total Number of All Tan 27 19 20 22 24 31 23.8

Substrata - Cover (Percent) I

Bare rock 1.1 1.7 3.9 1.7 4.4 6.1 3.2

Shell debris 3.3 - 0.6 1.7 0.9 •

Rock 0.6 - 2.2 2.2 0.8 i

J 1985-1989d_a atefiromKhmedcLabor_,s, Inc.(1992). Damaremcam_o_(n=3). Taxaand_av_fineach I

categoryarerankedaccordingtooverallmeans,thenlistedal_y ff theoverallmeansareequal.Totalpercentcovercanexceed1_

II

percentbecausemuRiplclayersweresampled.A dash(-)indicatesthetaxon/subsuammwasnot recordeduringthatsamplingperiod.

I

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140 I
Table A-24. Macrophyt the Mytiluseass , macroinvert emblage control ebate,plots andatsubstratum Point Sierraabundanc Nevdaes in

during spring 1991:

Taxon/Substratum Mean Deviation

Macrophytes - Cover (Percent)

i I Bossie CrustosUeapIumosa coraUines,unident. 7.8 6.7 7. 4.45

sp(p). 1.7 1.7

CaUithamnionpikeanum 1.1 1.9 Mastocarpus papiUatus 1.1 1.9

Petrocelis sp(p). 0.6 1.0

Redcrusts 0.6 1.0

TotalMacrophyteCover 19.6

I Macroinvertebrates - Cover (Percent)

Myt//us cz_//forn/mu_ 81.1 2.6

Ba/anus g/andu/a 6.1 5.1

PoUicipespolymerus

3.3 2.9

/.aTu/ad/g/ta//s 1.7 2.9

Anthopleura elegantissima 0.6 1.0

"CoUiseUa"scabra 0.6 1.0

TotalMacroinvertebrateCover 93.4

l Macroinvertebrates - Demity (No.10.187Sm2)

Lott/a d/g/ta//s 51.2 60.2

"Collisella"acabra 23.3 13.2 Lmt/a sp(p). 14.6 14.4

Lottia paradigitalis 5.0 6.2

/Lou/a .Mtor/na pe/tascutu/ata/p/ena 4. 3.53 7.0 4

Nutta///na ca//forn/_ 3.3 3.1

Lot_ g/gantea 0.3 0.6

Strongylocentrotus purpuratus 0.3 0.6

Tegulafunebralis 0.3 0.6

I Total Number of Macrophyte Taxa 7

Total Number of M_roinvertebrate Tan 14

Total Number of All Tara 21

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141

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I Table A-25. Macrophyte, at Point Sierramacroinvertebrate, Nevada for fall sampling and subpsetrariods tmnfromabundances 1985 toin1992.' the My_lus assemblage spring-cleared plots

Overall

I Taxon/Substratum 1985 1986 1987 1988 1989 1992 Mean

Macrophyte$ - Cover (Percent) Bossiella plumosa 6.7 20.0 27.2 20.0 30.0 17.3

Cladophora columbiana 8.9 8.3 10.6 6.1 18.9 8.8

i Cylind U/ rocarpusrugosus 2.2 12.8 2.2 1.1 11.1 2.8 5.4 _a sp(p). 0.6 7.8 5.0 0.6 0.6 6.1 3.5

Ra/fs/a sp(p). 2.2 12.8 0.6 1.1 1.7 3.1

Ana//pusjapon/cus 0.6 8.3 2.2 2.8 2.3

Pol Crustos ysiphonia ecoraHin sp(p).es,tmident. 3.9 2.2 06 11.7 - 3.3 3.9 0.6 2. 2.13

Endoc/ad/a mur/cma 1.7 2.8 0.6 0.6 2.8 1.4

Mastocaslmxpapillams 2.8 0.6 1.1 2.8 1.3

I Microcladia borealis 0.6 5.6 1.I 1.2 P,hodog/osmm affine 1.7 1.7 2.2 1.7 1.2

lridaea splendens 1.7 1.7 1.1 2.2 1.I

I Egregia menziesii - 5.0 0.8 Petrocelis sp(p). 3.3 - 1.1 0.7

Polys_honia_,_ryi 0.6 - 0.6 0.6 0.3

Polysiphonia nathanieUi - 1.7 0.3

I Brown Corallicrusts 1.1 0.2 na vancmnwiens/s - - 1.I 0.2

Pelvetia-Pelvetiopsis sp(p). - 1.1 0.2

Red crusts 1.1 - 0.2

Total MacrophyteCover 6.7 48.5 79.0 57.0 51.1 80.2

i Macroinvertebrates- Cover (Percemt) Ba/anus g/andu/a 8.3 6.1 2.2 8.9 5.0 2.2 5.4

Myt//us ca//forn/anus 0.6 - 0.6 2.2 7.8 12.2 3.9

_Nu_///nad/g/ta//s ca//formca 2.8 2.2 0.6 1. 1.11 4.4 0.6 2.2 3.9 0. 2.86 21..52

(:_hama/us sp(p). 3.3 - 2.2 0.6 0.6 1.1

"CoUisella"scabra 0.6 0.6 1.7 0.6 1.1 0.8

L/trOt/ha Pollicipesscupolyme tu/ma/p/ena rus 02.26 0.6 0.- 6 - 0.6 1.7 1.7 0.8.6

pe/ta 2.2 0.6 1.i 0.6

Lott/a parad/g/ta//s - 1.1 1.7 0.5

//matu/a 1.1 0.2

Tetrac//ta rubescens - 1.1 0.2

Phragmat_n_a ad/formca 0.6 - O.1

l Total MacroinvenebrateCover 22.3 10.1 7.9 21.1 23.5 22.3

Macroinvenebrat-eDs e_ity (No.lO.1875m-')

Lott/a d/g/ta//s 36.1 123.7 107.3 142.3 96.9 17.9 87.4

/,otfa sp(p). 2.1 191.7 56.3 75.0 33.3 125.0 80.6

"Collisella"scabra 20.6 97.3 33.7 50.6 22.9 23.3 41.4

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!

i

Table A-25. Macrophyte, macroinvertebrate, and substratum abundances in the Mytilus assemblage spring-cleared plots I

at Point Sierra Nevada for fall sampling periods from 1985 to 1992.1 (continued)

l Taxem/Substrattmu 1985 1986 1987 1988 1989 1992 Mean

Macroinvertebrates - Density (No.I0.1875 m_) I

L/trOt/ha scu/u/ma/phena 62.4 27.3 10.2 9.7 34.6 19.0 27.2

Lott/a pe/ta 34.1 2.7 7.0 4.7 4.0 16.0 11.4 l

Lott/a partu//g/ta//s 6.7 0.3 1.3 13.8 22.1 10.8 9.2 i

Nuttaliina ca//forn/ca 1.7 5.3 5.3 11.0 9.3 9.0 6.9

£mffa//matu/a 11.4 - 1.9 m

/.,/Wor/nakeenae - - 4.0 0.7 •

Tectura scutum - 4.2 0.7 I

Nucella emarginata 0.7 0.3 0.3 0.3 0.3

Kathar/na tun/cata 1.0 - 0.2 •

LepidocJfiton hartwegii - 0.3 - 0.1 I

Mopa//a musca_a 0.3 - O. 1

8trongy/ocentroms/napurams - 0.3 0. I

Tegula funebralix - 0.3 - 0.3 O.1 I

IB

Total Number of Macrophyte Taxa 3 12 13 14 12 15

Total Nmnber of Macroinvertebrate Ta,_ 16 12 9 13 12 14 l

Total Number of All Tm 19 24 22 27 24 29

- Cover Were) i

Substrata

Bare rock 73.3 46.7 26.7 37.2 37.8 18.3 40.0

Rock 2.2 10.6 12.8 23.3 2.8 2.8 9.1 •

Shell debris 0.6 1.1 1.1 0.5 I

1985-1969 dalaare from Khme_ Laboralories,Inc. (1992). Dataarc meam of threeplots(n_3). Taxa andsubstratawithineach •

category are rankedaccordingto overall means,thenlisted alphabeticallyffthe overall meatmarc equal. Total percentcover can exceed 100 II

percent becauseumlfiptelayers were sampled. A dash(-) indicatesthe mxmgsubsu-ammwasnot reconkd during_hatsamplingperiod.

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144 |
I Table A-26. Macrophyte, cleared plots atmacr Point oinvertebrate Sierra Nevada , andduring substratum springabundances 1991: in the Mytilus assemblage

i Spring-Cleared Fall-Cleared

Taxon/Substratum Mean S.D. z Mean S.D.

I Macropbytes - Cover (Percent)

Ra/_/a sp(p). 12.8 4.2 11.1 8.4

I Bossie Analipusj Ua_plumosa onicus 10. 7.86 163.7.5 136.9.7 17.6 5.4

Oadophom co/umb/ana 7.8 12.i

Crustose corallines,nnidea_t. 3.3 4.4 1.7 1.7

I 1 1.7 2.2 3.9

Endoc/ad/a mur_c_G m7

Iridaea sp/endens 1.7 2.9

Leathes/a d/fformb 1.1 1.9 2.2 3.9

I MCy_astocarpuapapill rugatus osus 01.1.6 1.9 1.0 1.1 1.1 1.9 1.9

Petrocelissp(p). 0.6 1.0 1.i 1.9

i _ sp(p). 0.6 1.0

TotalMacrophyteCover 49.7 41.1

I Macroinvertebrates - Cover(Percent)

Ba/anus g/andu/a 5.6 5.4 1.1 1.0

I Myt "CoilUusise¢ali Ua"forscabaiarnus a 41.1,4 31..95 6.7 1.1 10.1 1.9

Lottia digitalis 1.1 1.0 1.7 0.0

i Nuce//a emarg/nata 1.1 1.9 Tetracli_ rubeacens 1.1 1.9 2.8 2.6

Nutta///na o_//forn/ca 0.6 1.0 1.7 2.9

Pollicipespolymeras 0.6 1.0 -

L/ttor/na scum_a/p/ena 0.6 1.0 Lott/a parad/g/ta//s 0.6 1.0

Lott/a pe/ta 0.6 1.0

l Total MacroinvertebrateCover 15.6 16.9

Macroinvertebrates- DensRy(N0.10.1875m2)

Lot//a sp(p). 87.5 10.8 64.6 25.3

Lot//a d/8/ta//s 76.1 48.2 43.0 25.5

"Co///se//a"scabra 59.5 22.4 42.8 53.0 L/trOt/hascutu/ata/p/ena 35.4 61.3 59.3 77.3

Lott/a parad/g/ta//s 6.0 5.3 3.3 3.1

• __ cal_ornica 4.7 6.4 6.0 5.6

1 Lott/a pe/ta 3.7 4.7 2.0 2.0

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Table A-26. Macrophyte, mcroinvertebrate, and substratum abundances in the Myths assemblage I cleared plots at Point Sierra Nevada during spring 19917 (continued)

Taxon Spring-Cleared Fail-Cleared I/Substratum Mean S.D.2 Mean S.D.

Total Number of Macrophyte Tan 12 9 I

Total Number of Macroinvertebrate Taxa 12 10

Total Number of All Taxa 24 19 I

Substrata - Cover (Percent) I

Bare rock 38.9 3.9 48.9 16.2

Rock 5.6 4.2 7.8 4.2

!

t Data ave from Kinne_ Laboratories,Inc. (1992). Dataare means of threeplots(nffi3). Taxa andsubstratawithin each categoryare

rankedaccordi_ to the meansin the sprins-_leplots zred, thenlistedalphabe_ly if the means are equal. Totalpercent cover can I

exceed I00 percentbecause multiplelayerswere sampled. A dash(-) indicatesthe taxon/s_bstratumwas notrecordedin the plots

indicated.

2 S.D. = StandardDeviation I

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146 I

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I Table A-27. Macrophyt cleared plots e, maeroinvert at Point Sierra ebratNevada , andfor substrat fall sampling um abundanc periods esinfrmn the 198 Myff6/us to 1992. assem1blage fallOverall

I Taxon/Substratum 1986 19_7 I988 1989 1992 Mean

i Macrophytes - Cover (Percent) BossieLlaplumosa 0.6 58.3 40.0 17.2 15.6 26.3

U/va sift.p). 30.0 21.1 5.6 0.6 - 11.5

I CEgregia rustosemenziesii coraUines,tmident. 321.1 5.6 18.9 2.2 50.6.0 7.8 4.4 I1.0 8.1

Cy//ndroca_us rugosus 1.7 4.4 16.7 14.4 7.4

Ir/daea sp/endens - 16.1 8.9 0.6 - 5.1

I Rhodoglosssum Ciadophora columbiana affi_e 0.6 13.9 1.7 8. 3.93 3.9- 0.6 9.4 4.9 3.6

Ana//pux japon/eus - 0.6 5.6 6.1 1.1 2.7

Microcladia borea//s - 1.7 5.0 - - 1.3

I CoraUinavancouverier,sis 3.9 0.6 1.1 1.1 Ra/fs/a sp(p). 2.2 2.8 0.6 1.I

Polysiphonia sp(p). - 4.4 - - 0.9

I Endoc/sdm mw'/ema - 3.9 0.8 Petroce//s sp(p). 1.1 1.1 0.6 0.6 0.7

Mastocarp_papillams 1.7 0.6 - 0.6 0.6

Po/ys/phon/a hendryi 2.2 - - 0.4

I Ceramium Red filanmaeamnium ts 1.1 1.1 -- -

- 0.2 0.2

Pelvetia-eelPetiopsix sp(p). 0.6 - 0.1

P/ocam/um v/o/aceum 0.6 - - - 0.I

I Red crusts 0.6 - - 0.1

Total MacrophyteCover 89.6 149.0 94.6 56.3 52.3

I _rmes - Cever(Pereem)

Myt//us aa_/fonffanus 0.6 2.8 4.4 17.8 5.I

I Loa Nutta///na /a d/g/ta//s 0.6 3.3 3.9 2.2 I.i 2.2 ezz//foen/ca 2.8 4.4 1.1 1.7

"Collisella"$cabra 2.2 - 1.1 0.7

L/ttor/na scutu/ata/p/ena 0.6 1.i I.1 0.6

I _ parad/g/ta//s 0.6 1.1 1.1 0.6 ! Lotffape/ta 0.6 1.1 0.6 0.6 0.6

Pollieipe$polymerus 0.6 1.7 0.6 0.6

i Ba/am_ g/andu/a 1.1 0.6 0.6 0.5

Tarac//ta rubescens 0.6 0.6 1.I 0.5

Lep/doch//ona dent/ens 0.6 - - 0.1

Leptaster/sps(sp). - 0.6 - - O.1

I Phragmatoponm ca//forn/¢_ - 0.6 0.1 Strongy/ocentro_/nopwa_ 0.6 - O.1

Total MacroinveffebrateCover 0.6 5.1 17.5 16.7 26.8

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Table A-27. Macrophyte, macroinvertebrate, and substratum abundancesin the Mytilus assemblage fall- •

cleared plots at Point Sierra Nevada for fall sampling periods from 1986 to 1992.1 (continued) III

Overall I

Taxe_a/Substratum 1986 1987 1988 1989 1992 Mean

Maeroinvertebrotes - Density (No.t0.1875 m2) i

i

Lott/a sp(p). 320.8 29.2 39.6 56.3 108.3 110.8

"Collisella"scobra 5.2 18.8 72.9 55.6 25.6 35.6

Lo_ digitalis 12.3 24.6 36.1 54.9 21.3 29.8 I

Littorina scmulata/plena 41.2 3.7 15.8 31.0 24.7 23.3

LoU_ pe_a 12.7 5.0 18.7 9.3 39.6 17.1

Lottia paradigitalis 4.0 9.0 47.8 14.3 15.0 l

Nuttallina cai_ornica 6.0 8.0 16.8 19.0 9.3 11.8

Lott/a//macu/a 3.0 0.3 0.7 |

Nucellaenuzrginata 1.7 0.3 0.3 0.5

Lepk_Tc/utonadenffen$ 0.7 0.7 0.3 0.3 •

Leptasterkzs sp_). 0.3 0.3 0.7 0.3 1 _gy/ocem'roats purpumms 0.3 0.3 0.3 0.2

Lcnffagigantea 0.3 0.1

Mopa_a muscosa 0.3 0.1 •

Ocenebra circumtexta 0.3 0.1

Strongylocentrotusfranciscwms 0.3 0.1

Tegulafunebralis 0.3 0.1

Total Number of _hyte Tan 7 15 17 9 11 l

Total Nmmberof Macroinvettebro_ Tan 13 12 16 12 14 I

II Total Number of All Taxa 20 27 33 21 25

Substrota - Cever 0_em) i

Bare rock 33.9 11.1 23.9 34.4 30.6 24.6

Rock 21.7 6.1 14.4 2.2 1.1 9.1

Shelldebr_ - 0.6 - O.1 i

1986-1989damarefromKinmlkLaboratoriesInc. , (1992). Datazremea_ofthreeplot(ns =3).Taxaandsubslralawithin i

eachcategoryarerankedaccorc_gto overallmeam,thenli_edalplmbetic_yif theoverallmeama_ equal. Totalpercemcover •

canexceedI00percebntecausmultipl e laye ewresrerumpledA.dash(-)indica_ thetaxon/mb_'aannwasnotl_ecordedduring II

thatsamplingperied.

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148 I
I Table A-28. Macrophyte, assemblage control macroinvertebrate, plots at Point and Sierrasubstratum Nevada forabundances fall sampling in theperiods Endocladia/Mastocarpus from 1985 to 1992:

Taxon/Substratum 1985 1986 1987 1988 1989 1992 Mean

I Macrophytes - Cover (Percent)

Endoc/adia muricata 45.0 22.8 39.4 41.7 48.3 32.2 38.2

I Mas Redtoca crusts rpuspapillatus 12.8 5.0 2.2 3.9 18.3 2.8 3.9 12.2 - 2.8 - 8.9 1.8

GATGOR 0.6 4.4 - - - 0.8

i Petrocelis sp(p). 1.7 - - 0.3

Hesperophycus harveyanus 1.1 - - 0.2

Pelvetia-Pelvetiopsis sp(p). 0.6 - - 0.1

I TotalMacrophyteCover 66.2 33.9 57.7 48.4 60.5 35.0

Macroinvertebrates - Cover (Percent)

I Liuorina scutulma/plena 10.0 6.1 7.8 12.8 5.0 6.1 8.0

Chthama/ussl_). 0.6 - 0.6 0.6 7.8 1.6

Ba/anus g/andu/a 2.2 0.6 1.1 - - - 0.7

I L/uorina keenae 1.I 0.2 MytSus califomimms 0.6 - 0.1

Pagurus sp(p). - - 0.6 0.I

I Total MacroinvertebrateCover 12.8 7.3 8.9 13.4 5.6 15.6

i Macroinvertebrates - Density (No./0.1875 m2)

Littorina scumkna/plena 1156.4 1037.1 803.6 604.5 310.6 683.4 765.9

Littorina keenae - - 37.7 2.0 6.6

I Ionia digitalis 3.3 0.7 2.7 - 4.7 1.9 Tegulafunebralis 1.0 1.0 4.3 - 2.0 1.3 1.6

"CoUisella"$cabm 2.4 - 1.0 - 0.7 0.7

I Lep/doc Lonia peha _ona dent/ens 01..30 - 0.2O.1

Lott/a paradigtta//s - - 0.3 O.1

i Mopalia muscosa 0.3 - - - 0.1 Tectura scutum 0.3 - - O.1

TotalNnmber ofMaerophyteTaxa 6 5 2 3 2 2 3.3

I Total Number of Macroinvertebrate Tan 6 5 9 2 6 6 5.7

I To_talNumber of All Taxa 12 10 11 $ 8 8 9.0

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149

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!

Table A-28. Macrophyte, macroinvertebrate, and substratum abundances in the Endocladia/Mastocarpus I assemblage control plots at Point Sierra Nevada for fall sampling periods from 1985 to 1992.1

(continued)

Overall I

Taxon/Substratmn 1985 1986 1987 1988 1989 1992 Mean

Substrata- Cover(Percent) I

Bar Rocekrock 3632.12 610. 8.36 4448.43 4625.0.7 433.3 2.2 5118.7.3 427.0 9.2 I

1985-1989 data are from KinneficLaboratories,Inc. (1992). Dataaremeans of three plots(n=3). Taxa and substrataw_in each category I

are rankedaccording to overall means,then listedall_abelically if the overallmeans am equal. To_alpercentcover canexceed 100percent

because multiplelayers were sampk:d. A dash(-) indicatesthe taxon/substratumwas not recordedduring thatsamplingperiod.

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150

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I
I Table A-29. Macrophyt the Endocladia/Masto e, macroinvertebrate, carpus assemblag and esubstratm control plots abundances at Point in

Sierra Nevada during spring 1991}

Taxon/Substratum Mean Deviation

I Macrophytes - Cover (Percent)

I Endoc/ad/a R mur/co/a 33.3 14.2 ed crusts 6.7 11.6

Mastocarpus papi//atus 2.8 4.8

GATGOR 0.6 1.0

I Hesperophycus harveyanus 0.6 1.0

Total Macrophyte Cover 44.0

I Macroinvcrtebrates- Cover (Percent)

I Littorina Chthamahscutulata/plena _ sp(p). 54.4.6 6.9 7.7

Lott/a parad/gim//s 0.6 1.0

I Total Macroinvertebrate Cover 10.6

Macroinvertebrates - Density tno./0.1875 m_)

I Littorina scumima/plena 318.8 t 13.1

Loum sp07). 4.2 7.2

i Tegula funebralis 2.3 4.0 zar/amra_g/taUs 1.'I 2.1

L/trOt/ha keenae 1.3 2.3

"Co//ise//a" scabm 1.0 1.7

I Lo_a digitalis 1.0 1.0

Total Nmber of Maerophyte Tan 5

I Total Number of Macroinvertebrate Taxa 8

Total Number of AIIITan 13

I Smmr_ - Cover (Percent)

I Bar Rocke rock 48.9 27.8 6.7 1.9

I t DalaareftomKinmticLaboratorielns,¢.(1992). Dalaan:meansofflweepiols(nffi3).Taxaand mbsmuawithineachcategoryarc rankedaccordiagtothemeans,thenlistedalphabeticallyffthe

meansareequal. Totalpercentcovercanexceed100percembecausemultiplelayerswe_esampled.

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The DepmlmLent of the Interior Mission

As _ Nation s..principalconservationagency, the Department of the Interiorhas responsibilityfor I

mornm.ou.rna.tsormllyowned public lands and natural resources. This includesfosteringsound use Ig

ot ou.r,arm an.(]water.rasource.s; pro.tectingourfish, wildlife,and biologicaldiversity;preservingthe

er_. ronmen_..,ar_..cumJ.raivalues oTour..naUonalparks and historicalplaces;and providingfor the mE

enjoyment ot onetnmugn outooorrecreason. The Department assesses our energy and mineral •

resourcesand worksto ensure that their developmentis in the best interestsof all our people by

encouraging stewardshipand citizen participation intheir care. The Department also has a major

responsibilityfor American Indian msarvation communites and for people who live in island

territodas under U.S. administration. I

IB

The Minerals Management Service Mission

As a bu.r_....,of the Department of the Interior, the Minerals Management Service's (MMS) primary

msponsll_imasare to manage me mineral resourceslocated on the Nation'sOuter Continental Shelf i

(OCS), collect rovenue from the Federal OCS and onshore Federal and indian lands, and distribute

those revenues.

mm

Moreover, in working to meet its responsibilities, the Offshore Minerals Management Program I

administers the OCS compeUtiveleasing programand oversees the safe and environmentallysound

exploration and productionof our Nation's offshore natural gas, oil and other mineral resources. The

MMS Royalty Management Program meets its responsibilitiesby ensuringthe efficient,timely and IB

accurate collectionand disbursementof revenue from mineral leasingand productiondue to Indian II

tribes and allottees, States and the U.S. Treasury.

The MMS strives to fulfillits responsibilitiesthroughthe general guidingprinciplesof: (1) being B

responsive to the public's concerns and interestsby maintaininga dialogue withall potentialJyaffected i

parties and (2) carryingout its programswith an emphasis on working to enhance the qualityof lifefor

all Americans by lending MMS assistance and expertise to economicdevelopment and environmental

prov_on. I