NOAA Technical Memorandum NMFS-NWFSC-103

U.S. DEPARTMENT OF COMMERCE

National Oceanic and Atmospheric Administration

National Marine Fisheries Service

A Synthesis of Diets

and Trophic Overlap

of Marine Species

in the California Current

November 2009
NOAA Technical Memorandum

NMFS-NWFSC Series

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not imply endorsement by the National Marine Fisheries 

Service, NOAA.

This document should be referenced as follows:

Dufault, A.M., K. Marshall, and I.C. Kaplan. 2009. A 

synthesis of diets and trophic overlap of marine species in 

the California Current. U.S. Dept. Commer., NOAA Tech. 

Memo. NMFS-NWFSC-103, 81 p. 
NOAA Technical Memorandum NMFS-NWFSC-103

U.S. DEPARTMENT OF COMMERCE

National Oceanic and Atmospheric Administration

National Marine Fisheries Service

A Synthesis of Diets

and Trophic Overlap

of Marine Species

in the California Current

Aaron M. Dufault,

1

 Kristin Marshall,

2 and Issac C. Kaplan

Northwest Fisheries Science Center

Conservation Biology Division

2725 Montlake Boulevard East

Seattle, Washington 98112

Present affiliation:

California State University

Department of Biology

18111 Nordhoff Street

Northridge, California 91330

Present affiliation:

Colorado State University

Graduate Degree Program in Ecology

1472 Campus Delivery

Fort Collins, Colorado 80523

November 2009

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Table of Contents 

List of Figures...............................................................................................................................................v

List of Tables ..............................................................................................................................................vii

Executive Summary .....................................................................................................................................xi

Acknowledgments......................................................................................................................................xiii

Introduction...................................................................................................................................................1

Methods ........................................................................................................................................................3

Data...........................................................................................................................................................3

Data Analysis............................................................................................................................................4

Functional Groups................................................................................................................................4

Species Data .........................................................................................................................................4

Food Web.............................................................................................................................................5

Results...........................................................................................................................................................6

Diet Summary...........................................................................................................................................6

Cluster Analysis: Functional Group Level ...............................................................................................6

PSI: Functional Group Level....................................................................................................................6

Food Web Structure Analysis...................................................................................................................7

Analyses for Fish at the Species Level.....................................................................................................7

Discussion.....................................................................................................................................................9

Figures 1–17 and Tables 1–5 ......................................................................................................................11

References...................................................................................................................................................37

Appendix A: Sources for Diets...................................................................................................................45

Fish .........................................................................................................................................................45

Seabirds ..................................................................................................................................................50

Marine Mammals....................................................................................................................................51

Invertebrates ...........................................................................................................................................52

Appendix B: Tables of Functional Group Diets .........................................................................................55

Appendix C: Tables of Fish Species Diets..................................................................................................67

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List of Figures 

Figure 1. Dendrogram of California Current diets derived from the hierarchical cluster analysis............12

Figure 2. Percent diet composition of feeding guilds A and B..................................................................13

Figure 3. Percent diet composition of feeding guilds C and D ..................................................................13

Figure 4. Percent diet composition of feeding guild E...............................................................................14

Figure 5. Percent diet composition of feeding guild F...............................................................................14

Figure 6. Percent diet composition of feeding guild G..............................................................................15

Figure 7. Percent diet composition of feeding guild H..............................................................................16

Figure 8. Percent diet composition of feeding guild I................................................................................16

Figure 9. Percent diet composition of feeding guild J ...............................................................................17

Figure 10. Visual representation of California Current food web structure...............................................17

Figure 11. Dendrogram of California Current fish-only diets derived from the hierarchical cluster 

analysis........................................................................................................................................................18

Figure 12. Percent diet composition of feeding guild A from the species-level hierarchical cluster 

analysis........................................................................................................................................................19

Figure 13. Percent diet composition of feeding guilds B and C from the species-level hierarchical 

cluster analysis............................................................................................................................................19

Figure 14. Percent diet composition of feeding guild D and E from the species-level hierarchical 

cluster analysis............................................................................................................................................20

Figure 15. Percent diet composition of feeding guilds F and G from the species-level hierarchical 

cluster analysis............................................................................................................................................20

Figure 16. Percent diet composition of feeding guild H from the species-level hierarchical cluster 

analysis........................................................................................................................................................21

Figure 17. MANOVA plot of the PSI of species-level data ......................................................................22

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List of Tables 

Table 1. Vertebrate species included in the functional group analysis and their respective 

proportional biomass within the functional group ......................................................................................23

Table 2. Invertebrate taxa included in each functional group....................................................................27

Table 3. PSI of California Current functional groups................................................................................29

Table 4. Comparison of our California Current food web to other marine food webs, using common 

food web structure properties......................................................................................................................33

Table 5. PSI for all fish species diets.........................................................................................................34

Table B-1. Diet composition by percent weight for members of feeding guild A.....................................55

Table B-2. Diet composition by percent weight for members of feeding guild B.....................................56

Table B-3. Diet composition by percent weight for members of feeding guild C.....................................57

Table B-4. Diet composition by percent weight for members of feeding guild D.....................................58

Table B-5. Diet composition by percent weight for members of feeding guild E.....................................59

Table B-6. Diet composition by percent weight for members of feeding guild F .....................................61

Table B-7. Diet composition by percent weight for members of feeding guild G.....................................62

Table B-8. Diet composition by percent weight for members of feeding guild H.....................................63

Table B-9. Diet composition by percent weight for members of feeding guild I ......................................66

Table B-10. Diet composition by percent weight for members of feeding guild J....................................66

Table C-1. Diet composition by weight for albacore tuna, a member of feeding guild B.........................68

Table C-2. Diet composition by weight for arrowtooth flounder, a member of feeding guild H ..............68

Table C-3. Diet composition by weight for Bering skate, a member of feeding guild E...........................69

Table C-4. Diet composition by weight for big skate, a member of feeding guild E ................................69

Table C-5. Diet composition by weight for black rockfish, a member of feeding guild B........................69

Table C-6. Diet composition by weight for blue lanternfish, a member of feeding guild A .....................69

Table C-7. Diet composition by weight for blue rockfish, a member of feeding guild B..........................69

Table C-8. Diet composition by weight for California headlightfish, a member of feeding guild ............69

Table C-9. Diet composition by weight for canary rockfish, a member of feeding guild A......................70

Table C-10. Diet composition by weight for Chinook salmon, a member of feeding guild B ..................70

Table C-11. Diet composition by weight for darkblotched rockfish, a member of feeding guild A .........70

Table C-12. Diet composition by weight for deepsea sole, a member of feeding guild D ........................70

Table C-13. Diet composition by weight for Dover sole, a member of feeding guild D...........................71

Table C-14. Diet composition by weight for English sole, a member of feeding guild D.........................71

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Table C-15. Diet composition by weight for garnet lampfish, a member of feeding guild C....................71

Table C-16. Diet composition by weight for giant grenadier, a member of feeding guild E.....................71

Table C-17. Diet composition by weight for greenstriped rockfish, a member of feeding guild A ..........72

Table C-18. Diet composition by weight for jack mackerel, a member of feeding guild A......................72

Table C-19. Diet composition by weight for lingcod, a member of feeding guild H ................................72

Table C-20. Diet composition by weight for longnose skate, a member of feeding guild E.....................73

Table C-21. Diet composition by weight for longspine thornyhead, a member of feeding guild H..........73

Table C-22. Diet composition by weight for northern anchovy, a member of feeding guild A ................73

Table C-23. Diet composition by weight for northern lampfish, a member of feeding guild C................73

Table C-24. Diet composition by weight for northern smoothtongue, a member of feeding guild G .......74

Table C-25. Diet composition by weight for Pacific grenadier, a member of feeding guild F..................74

Table C-26. Diet composition by weight for Pacific hake, a member of feeding guild A.........................74

Table C-27. Diet composition by weight for Pacific halibut, a member of feeding guild H.....................74

Table C-28. Diet composition by weight for Pacific herring, a member of feeding guild A.....................75

Table C-29. Diet composition by weight for Pacific mackerel, a member of feeding guild A..................75

Table C-30. Diet composition by weight for Pacific ocean perch, a member of feeding guild A.............75

Table C-31. Diet composition by weight for Pacific sanddab, a member of feeding guild E....................75

Table C-32. Diet composition by weight for Pacific sardine, a member of feeding guild A.....................76

Table C-33. Diet composition by weight for Pacific viperfish, not a member of a feeding guild .............76

Table C-34. Diet composition by weight for petrale sole, a member of feeding guild E ..........................76

Table C-35. Diet composition by weight for pygmy rockfish, a member of feeding guild A...................76

Table C-36. Diet composition by weight for redstripe rockfish, a member of feeding guild A ................76

Table C-37. Diet composition by weight for rex sole, a member of feeding guild D................................76

Table C-38. Diet composition by weight for rosethorn rockfish, a member of feeding guild G ...............77

Table C-39. Diet composition by weight for rougheye rockfish, a member of feeding guild G ...............77

Table C-40. Diet composition by weight for sablefish, a member of feeding guild H..............................78

Table C-41. Diet composition by weight for sharpchin rockfish, a member of feeding guild A...............78

Table C-42. Diet composition by weight for shortspine thornyhead, a member of feeding guild A..........79

Table C-43. Diet composition by weight for sixgill shark, a member of feeding guild F .........................79

Table C-44. Diet composition by weight for sleeper shark, a member of feeding guild H .......................79

Table C-45. Diet composition by weight for soupfin shark, a member of feeding guild H.......................80

Table C-46. Diet composition by weight for spiny dogfish, a member of feeding guild A.......................80

Table C-47. Diet composition by weight for splitnose rockfish, a member of feeding guild A................80

Table C-48. Diet composition by weight for spotted ratfish, a member of feeding guild H......................80

Table C-49. Diet composition by weight for twoline eelpout, a member of feeding guild G....................81

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Table C-50. Diet composition by weight for widow rockfish, a member of feeding guild G ...................81

Table C-51. Diet composition by weight for yelloweye rockfish, a member of feeding guild H..............81

Table C-52. Diet composition by weight for yellowtail rockfish, a member of feeding guild G ..............81

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Executive Summary 

A key step toward ecosystem-based management is to better understand how interactions 

within food webs affect species of commercial and conservation importance. Here we provide 

comprehensive diet information and food web analysis for major taxa within the California 

Current ecosystem, including fish, marine mammals, birds, and invertebrates. 

We synthesized 75 published diet studies from this ecosystem and calculated 

representative diets for each species or aggregated functional group. We assessed diet 

relatedness using hierarchical cluster analysis and calculated diet overlaps based on percent 

similarity index (PSI). Both analyses were performed on functional group data and also 

separately for each vertebrate species. 

Cluster analysis identified distinct feeding guilds and revealed both intuitive and novel 

diet similarities between several species and functional groups. One intuitive example is that 

functional groups preying on euphausiids, a key forage species in the California Current, show a 

high amount of overlap. A novel example is the significant diet overlap of shallow small 

rockfish and baleen whales (e.g., grey whales [Eschrichtius robustus]), both of which consume 

large amounts of benthic invertebrates. 

Functional groups were highly significant in explaining the PSI differences between 

species, which suggests that key ecological interactions will be preserved in ecosystem models 

that use these functional groups. A visual representation of the complete food web and 

calculation of food web statistics suggest that there are strong similarities between the food webs 

of the California Current and the Benguela Current, a similar upwelling-driven eastern boundary 

current off the southwest coast of Africa. 

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Acknowledgments 

This work was supported by grants to support ecosystem models and management from 

the Gordon and Betty Moore Foundation and the David and Lucille Packard Foundation. Nick 

Tolimieri assisted with the MANOVA plots, Cameron Ainsworth pointed us toward the 

hierarchical clustering algorithms in R, Jameal Samhouri suggested the use of FoodWeb3D, and 

Eliza Heery provided assistance with R. Data and feedback were supplied by more individuals 

than can be listed here, but key contributors included John Field, Richard Brodeur, Todd Miller, 

and Patrick Ressler. Brad Hanson and Mike Ford improved our diet sources for marine 

mammals. We are deeply indebted to more than 75 authors listed in Appendix A, who 

performed the diet studies summarized here. 

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Introduction 

Beginning in 1999, a series of high-level commissions on marine policy have called for 

implementation of ecosystem-based management (EBM) of our oceans (NOAA 1999, Pew 

Oceans Commission 2003, U.S. Commission on Ocean Policy 2004). EBM attempts to consider 

the entire ecosystem, to maintain multiple ecosystem services as well as system resilience, and to 

focus on cumulative impacts of multiple sectors rather than focusing on a single species or sector 

(McLeod et al. 2005). As McLeod et al. (2005) stated, 

Specifically, ecosystem-based management: 

• emphasizes the protection of ecosystem structure, functioning and key processes; 

• is place-based in focusing on a specific ecosystem and the range of activities 

affecting it; 

• explicitly accounts for the interconnectedness within systems, recognizing the 

importance of interactions between many target species or key services and other 

nontarget species; 

• acknowledges interconnectedness among systems, such as between air, land, and 

sea; and 

• integrates ecological, social, economic, and institutional perspectives, recognizing 

their strong interdependences.

A key step toward addressing this third goal of EBM is to better understand how trophic 

interactions within food webs affect species of commercial and conservation importance (Pauly 

et al. 2002). In this paper, we provide comprehensive diet information and food web analysis for 

major taxa within the California Current ecosystem, including fish, marine mammals, birds, and 

invertebrates. We quantify trophic interactions for marine species by summarizing peerreviewed literature and technical reports related to diet studies. Our work builds on Field (2004), 

who constructed an Ecopath with Ecosim food web model for the California Current. Field’s 

food habits data and references served as the initial sources for our analysis, which we then 

supplemented with additional recent and historical publications. Other key literature reviews and 

field studies that we have incorporated include Buckley et al. (1999), Brodeur and Pearcy 

(1984),Wakefield (1984), Sydeman et al. (1997), Pauly et al. (1998), Hunt et al. (2000), and 

Miller and Brodeur (2007), among others. We also included food habits information from trawl 

surveys such as Dark and Wilkins (1994) and Weinberg et al. (2002). The complete list of diet 

sources is described in the Methods section and Appendix A. 

Diet information such as the summaries presented here can be used to parameterize 

multispecies ecosystem models for use in quantitative projections, or to provide simple 

qualitative advice regarding trophic effects within the marine food web. In the context of 

ecosystem models, diets form the matrix of interspecies interactions. In these models, diets are 
either fixed proportions, or more frequently vary in response to predator and prey abundance 

following a functional response (e.g., Atlantis, Ecosim, Walters et al. 2000, Christensen and 

Walters 2004, Fulton 2004, Fulton et al. 2007). For instance, the diets estimated in this study 

have been incorporated into two Atlantis ecosystem models of the U.S. West Coast and 

California Current (Kaplan and Levin 2009, Horne et al. in prep.). In the context of U.S. fishery 

management plans, decision makers may soon need to identify the predators and prey of species 

of commercial or conservation concern. Such requirements for strategic advice can be addressed 

graphically (as we have done in this report) or diets can be converted to food webs to 

qualitatively identify interactions within these food webs (Dambacher et al. 2002). The diet 

information provided in our synthesis can serve both these quantitative and qualitative roles. 

Ecosystem models and EBM policies often aggregate species into functional groups or 

feeding guilds on the basis of diet, habitat, life history parameters, or fishery targeting. This is a 

necessary simplification for reasons related to field identification of species or specificity of 

catch or landings data, for computational reasons, and for ease of interpretation. However, 

ecological interactions such as intragroup competition and predation are lost in the formation of 

functional groups. Furthermore, functional groups are often formed based on expert opinion, as 

a compromise between the characteristics listed above. The ecosystem modeling literature 

suggests some guidelines for functional group formation, such as not aggregating species with 

drastically different turnover times or other rates, and not aggregating predators and prey 

(O’Neill and Rust 1979, Cale and Odell 1980, Gardner et al. 1982, Fulton et al. 2003). However, 

rarely have ecosystem modelers compared functional groups formed using these rules of thumb 

to those formed from statistical analyses of diet data, such as hierarchical clustering algorithms. 

The goals of this study are to summarize diet information for key marine species of the 

U.S. West Coast at both the functional group and species levels, to identify key forage species in 

the California Current and diet overlaps between predators, to compare the functional groups 

from an Atlantis ecosystem model of the California Current (Brand et al. 2007, Kaplan and 

Levin 2009, Horne et al. in prep.) to functional groups based on diet similarity, and to compare 

this food web to other published marine food webs. 

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Methods 

Data 

We summarized the diets of marine species of the California Current ecosystem, which 

spans the entire U.S. West Coast. We compiled 75 sources, with 52 fish species comprising 22 

functional groups (Appendix A). We also compiled diets from marine mammal, seabird, and 

invertebrate functional groups (Appendix A). Fish diets were from peer-reviewed journals and 

technical reports from 1957 to 2008, but primarily from the 1970s to present. The data span the 

oceanographic and ecological regime shift in the northern California Current in the late 1970s 

(Hare and Mantua 2000). Diet data for marine mammals relied heavily on a marine mammal 

diet review (Pauly 1998) and a review for seabird diets (Hunt 2000). We used diet data for 

invertebrates primarily from Field (2004) and a limited number of other sources. When diet data 

for a particular species were not available within the California Current, we included diets from 

other areas (e.g., Bering Sea) and noted these sources. 

Our analysis focused on functional groups defined for the Atlantis ecosystem model of 

the California Current (Brand et al. 2007, Kaplan and Levin 2009). Most of these functional 

groups typically include several species. However, several functional groups are comprised of a 

single commercially important fish species, as these species are of particular interest to those 

working within the California Current. 

For fish functional groups that were composed of multiple predator species, we weighted 

the diets by the relative biomass of the species within the functional group, based on NOAA 

Northwest Fisheries Science Center trawl survey data from 1998 to 2003 (Turk et al. 2001, 

Builder Ramsey et al. 2002, Keller et al. 2005, 2006a, 2006b, 2007). Prior to aggregating 

predator species into functional groups, we summarized all diet information for each predator 

species, differentiating between adult and juvenile predators and including percent by mass or 

volume diet data. When more than one data source was available for a species, we weighted 

each source by its sample size. Within studies, categories labeled as “unidentified” (e.g., 

unidentified flatfish or crustacea) were split among corresponding groups in the diet according to 

their existing relative weights. Specifically for “unidentified rockfish” as a prey item, we 

determined prey functional groups by considering the spatial overlap of predators and potential 

prey, as determined from trawl survey data (Turk et al. 2001, Builder Ramsey et al. 2002, Keller 

et al. 2005, 2006a, 2006b, 2007). 

Diet data and population biomass estimates were available for most marine mammal, 

seabird, and invertebrate functional groups. In the absence of biomass estimates (most 

commonly for invertebrate groups), we inferred the final diet proportion based on related 

available literature (Appendix A). We adapted the majority of invertebrate diets from Field 

(2004). 

3
Where possible, we differentiated between diets of adult predators and juvenile predators. 

For several functional groups, only one or a few species had published juvenile data, which we 

then used to calculate the juvenile diet data using the same method described above. In the 

absence of juvenile data, we assumed diets of juveniles were the same as that for adults (unless 

otherwise noted). 

Table 1 summarizes the vertebrate species in each functional group and their relative 

proportion based on biomass. The species that comprise each functional group are ordered from 

largest to smallest proportion within the group, as stated in the first sentence for each group in 

Appendix A. Invertebrate functional groups are summarized in Table 2 and Appendix A. 

Data Analysis 

Functional Groups 

To compare diet similarities between functional groups, we created a dendrogram using 

an agglomerative hierarchical cluster analysis. We first formed a complete diet matrix 

containing predator functional groups as rows and prey functional groups as columns. A 

Euclidian distance matrix was created in the statistical program R (MASS package, R version 

2.9.1, University of Auckland, New Zealand) from the diet data. The data were clustered using 

the complete (MAX) method of linkage to create a dendrogram. We used the dendrogram in 

conjunction with the raw diet data to establish feeding guilds and to more effectively display 

functional group diet data. 

We calculated percent similarity index (PSI) to assess diet overlap between functional 

groups. Complete diets of fish feeding guilds were arranged in a matrix similar to that described 

above for the cluster analysis. We used the PSI methods as described by Miller and Brodeur 

(2007), adapted from Schoener (1974), and implemented in the statistical software R. Diet 

overlaps were deemed significant if their index value was greater than 60 (Wallace and Ramsay 

1983). 

5.1 100

1

, ×⎥

⎦

⎤ ⎢

⎣

⎡ ∑ −−= =

n

k

ji jkik PSI pp

where p is the proportion of diet of predator i or j that is comprised of prey species k (Miller and 

Brodeur 2007). 

Species Data 

Our fish functional groups were defined prior to this work (Brand et al. 2007), based on a 

compromise between qualitative diet information, fishery targeting, habitat use, and management 

concerns. Here we used species-level quantitative fish diet information to assess how these 

original functional groups compare to feeding guilds suggested by hierarchical clustering and the 

PSI. Our methods for species data analysis were hierarchical cluster analysis and PSI, similar to 

the approach for functional groups. We calculated average PSI values and proportion of 

significant diet overlaps for species pairs within versus between functional groups. We analyzed 

4
the significance of these values by performing a multivariate analysis of variance (MANOVA) in 

Primer (Primer, Version 6.1.11 with Permanova+, Version 1.0.1, Plymouth Marine Laboratory, 

Plymouth, United Kingdom). 

Food Web 

We constructed a visual representation of the complete California Current food web using 

the software Foodweb3d (Ver. 1.01, 2002, Pacific Ecoinformatics and Computational Ecology 

Laboratory, Berkeley, California). We used the diet data at the functional group level. 

Constructing a three-dimensional food web at the species level would require further resolution 

of all predators and prey to species-level taxonomic resolution. 

For the food web analysis, any juvenile prey items were aggregated with their adult 

counterpart. This ensured that there were no species duplicated within the food web. 

Additionally, many published food webs lack any distinction between life stages of the included 

species (Opitz 1996, Yodzis 1998, Link 2002). 

Summary statistics that we used to describe food web characteristics (Pimm 1980) 

include: 

%B (basal species)—the percent of species (functional groups) that have no prey linkages 

in the food web (These groups can be autotrophs or groups that lack diet data.), 

%T (top species)—the percent of species with no known predator, and

%I (intermediate species)—the percent of species that are neither basal nor top species. 

We also describe the food web with metrics from Dunne et al. (2004), including: 

L/S—links per species, 

C = L/S2

—connectance, 

%O (omnivorous)—the percent of species that are omnivorous (have trophic linkages to 

multiple trophic levels), and 

%C (cannibalistic)—the percent of species that are cannibalistic. 

We compared this study’s food web to others compiled by Dunne et al. (2004). 

5
Results 

Diet Summary 

Diet sources for each species or functional group are included in Appendix A. Complete 

diet summaries of functional groups are listed in Appendix B and complete diets of fish species 

are listed in Appendix C. 

Cluster Analysis: Functional Group Level 

Results from the hierarchical cluster analysis are shown in Figure 1. Based on this 

dendrogram, we subjectively formed 10 feeding guilds (boxes in Figure 1) that we used to 

structure the discussion below. 

Feeding guilds generally contain species with similar diets (Figure 2 through Figure 9). 

Benthic detritivores and meiobenthos make up feeding guild A, primarily preying on detritus 

(Figure 2). Guild B contains groups feeding on large zooplankton (e.g., euphausiids, Figure 2). 

Guild C contains piscivorous groups targeting small planktivorous fishes (Figure 3). Guild D 

includes invertebrate consumer groups that prey on phytoplankton and small zooplankton groups 

(Figure 3). Transient killer whales (Orcinus orca) do not share diets with any groups and are 

excluded from all guilds (Figure 3). Guild E functional groups feed on benthic invertebrate taxa 

in high proportions, particularly deposit feeders such as polychaetes, amphipods, and other small 

crustaceans (Figure 4). Guild F preys primarily on various benthic invertebrate taxa such as 

herbivorous grazers (urchins) and megazoobenthos (crabs) (Figure 5). Guild G feeds on a 

variety of zooplankton groups including large zooplankton (euphausiids), mesozooplankton 

(copepods), and gelatinous zooplankton (jellyfish) (Figure 6). Other components of this guild’s 

diets vary considerably by species, from phytoplankton to fish. Guild H contains largely high 

trophic level carnivorous functional groups (Figure 7). This group can be subdivided into groups 

specializing in benthic versus pelagic prey, although overlaps exist. Large demersal predators 

(lingcod [Ophiodon elongatus]), pelagic sharks, diving seabirds, and large flatfish all consume 

large amounts of pelagic prey such as small planktivores and miscellaneous nearshore fishes. 

The remaining groups including skates and rays, deep small rockfish, and deep miscellaneous 

fishes target benthic prey such as deposit feeders (amphipods and small crustacea), deep 

miscellaneous fishes, and shrimp (Figure 7). Guild I is composed of high trophic level 

functional groups that prey heavily on cephalopods (squid) (Figure 8). Guild J contains two 

invertebrate functional groups which rely heavily upon detritus in their diet (Figure 9). 

PSI: Functional Group Level 

PSIs for functional groups revealed few diet overlaps higher than 60% (Table 3). Of 

these significant diet overlaps, a large proportion occurred in guild B, which feed primarily on 

zooplankton (Table 3, Figure 2). These groups include Pacific hake (Merluccius productus), 

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canary rockfish (Sebastes pinniger), shallow large rockfish, small planktivores, cephalopods, and 

large planktivores. Functional groups preying on small planktivorous fish also had significant 

diet overlaps, including Chinook salmon (Oncorhynchus tshawytscha), albacore tuna (Thunnus 

alalunga), migrating seabirds, and surface seabirds. Further significant diet overlaps occurred 

for English sole (Parophrys vetulus), small flatfish, small cetaceans, and toothed whales, but are 

not surprising given the similar dietary habits of each group. We calculated a high percent 

similarity for baleen whales and shallow small rockfish such as rosethorn (Sebastes 

helvomaculatus) and greenstriped (S. Elongatus) rockfish. These species are in feeding guild E 

and prey heavily on benthic deposit feeders (e.g., primarily small crustacea and polychaetes) and 

large zooplankton (euphausiids). 

Food Web Structure Analysis 

Food web metrics indicate that the California Current is highly connected, has a high 

proportion of cannibalistic and basal species, and has a low proportion of omnivorous species 

(i.e., those that prey on multiple trophic levels) when compared to other food webs (Table 4, 

Figure 10). The number of functional groups included in our food web is also comparable to 

those reported in Dunne et al. (2004), despite the aggregation of our species into functional 

groups. The Benguela Current food web is comparable to the California Current food web in 

that it is an eastern boundary current with strong upwelling and high abundances of clupeids and 

hake (Merluccius spp.). Yodzis’ (1998) Benguela food web is highly comparable to ours across 

most metrics (connectivity, links/species, and percent intermediate and top predators). However, 

relative to the Benguela Current (located off the southwest coast of Africa), the California 

Current has a lower proportion of omnivorous species and a higher percentage of basal groups 

and cannibalistic groups. These characteristics of the California Current are also apparent when 

comparing it to the three other reef and shelf food webs (Table 4) (Opitz 1996, Link 2002). 

It is likely that the California Current food web’s increased proportion of basal species is 

due to sampling methods. The number of basal species is highly sensitive to the completeness of 

the food web. Our food web, like many others used for ecosystem modeling, is biased toward 

fish species, while basal and low trophic level species are aggregated into larger functional 

groups, decreasing the number of basal groups represented in the food web. The northeast U.S. 

shelf (Link 2002) food web has fewer species per functional group than our representation of the 

California Current. The taxonomic groups included by Link (2002) are very similar, however. 

We were unable to accurately enumerate total species that contributed to the food web 

because our literature sources frequently only identified prey to functional group. However, we 

estimate approximately 200 (±50) vertebrate and invertebrate species in total were included in 

this food web. 

Analyses for Fish at the Species Level 

Cluster analysis of species-level data for fish yielded eight feeding guilds similar to those 

described above for functional groups (Figure 11). A large number of species clustered in guild 

A, all feeding heavily on large zooplankton (Figure 12). Pacific viperfish diets were dissimilar 

from any other species and were excluded from feeding guilds. Guild B contains species that 

feed primarily on small planktivorous fish (Figure 13). Guild C contains two species of lampfish 

7
feeding largely on mesozooplankton (e.g., copepods) (Figure 13). Guild D includes four species 

of flatfish feeding on small benthic prey, such as benthic carnivores (polychaetes) and deposit 

feeders (small crustaceans). Guild E species, ranging from skates to flatfish, fed on a variety of 

benthic fauna including small flatfish and shrimp (Figure 14). Guild F species largely feed on 

cephalopods (squid) and to a lesser degree on high trophic level fishes (Figure 15). Guild G 

species feed on a variety of large zooplankton (euphausiids), gelatinous zooplankton (jellyfish), 

deposit feeders (amphipods), and benthic herbivorous grazers (snails, urchins, etc.). Guild H 

contains species feeding on various fish (e.g., Pacific hake and small planktivores) and benthic 

invertebrates including deposit feeders (amphipods) and megazoobenthos (crabs) (Figure 16). 

The cluster analysis for fish at the species level (Figure 17) indicated that most species 

had very similar diets to other species within their functional group. For example, the small 

flatfish group, made up of Dover sole (Microstomus pacificus), rex sole (Glyptocephalus 

zachirus), Pacific sanddab (Citharichthys sordidus) and deepsea sole (Embassichthys bathybius) 

all cluster within species guild D. Similarly, the three species within the skate functional group 

all cluster into guild E. The species-level dendrogram reveals other similarities that might be 

expected based on our preconceptions about functional groups, such as clustering of sardines and 

anchovies, arrowtooth flounder (Atheresthes stomias) and Pacific halibut (Hippoglossus 

stenolepis), widow (Sebastes entomelas) and yellowtail rockfish (S. flavidus), and sixgill 

(Hexanchus griseus) and sleeper sharks (Somniosus pacificus). 

A few species do not cluster close to others within their functional group. The deep 

vertical migratory group, consisting of Pacific viperfish (Chauliodus macouni), blue lanternfish 

(Tarletonbeania crenularis), California headlightfish (Diaphus theta), garnet lampfish 

(Stenobrachius nannochir), and northern lampfish (S. leucopsarus), is only loosely related 

according to the species-level cluster analysis. Pacific viperfish (Figure 11 and Figure 12) diets 

are dissimilar from those of other species within this functional group, which generally feed on 

large and small zooplankton. Pacific viperfish feed almost exclusively on other deep vertically 

migrating fish (e.g., Myctophids) and were not assigned to a feeding guild for this reason. Blue 

lanternfish and California headlightfish cluster in group A, though their diets are less related. 

The remaining two species, garnet lampfish and northern lampfish, both cluster together in 

species guild C. 

PSIs between fish species support the appropriateness of the majority of our functional 

groups for explaining diet variation between species (Table 5). On average, PSI was higher 

between species within a single functional group than between species in different groups (37.2 

to 19.6, respectively). In addition, significant diet overlaps (>60%) were three times more likely 

within a functional group (21% and 7%, respectively). We found our functional groups to be 

highly significant in explaining the PSI between species (MANOVA, F13 = 2.6138, p = 0.001). 

A MANOVA plot of the species-level fish diets (Figure 17) identifies seven major axes of prey 

species, including large zooplankton, benthic invertebrates, Pacific hake and small pelagic fish; 

these are similar to the prey that define the species-level feeding guilds identified in the 

dendrogram (Figure 11). 

8
Discussion 

The diet summaries presented in Figure 2 through Figure 9, Figure 12 through Figure 16, 

and Appendix B and Appendix C present a synoptic view of marine species diets in the 

California Current. We have attempted to compile a comprehensive list of more than 75 sources 

of diet information (Appendix A). The diet summaries provide a convenient representative diet 

per predator species or functional group, averaging across disparate studies. For instance, our 

estimate that 40% of yellowtail rockfish diets are large zooplankton (euphausiids) is the 

weighted average of four studies, including but down-weighting a study of only 22 fish by 

Pereyra et al. (1969) that attributed only 13% of the diet to large zooplankton. In other cases our 

diet summaries for a predator stem from a single study (e.g., English sole) or several studies 

reporting similar diet composition (e.g., all four diets studies for canary rockfish indicate heavy 

predation on euphausiids and other large zooplankton). In these cases our summaries do not add 

any novel interpretation but may provide an easy reference for future applications. 

Key prey functional groups were identified through both the functional group-level and 

species-level analyses. Many predator functional groups preyed heavily on the following, ranked 

by order of importance: large zooplankton (primarily euphausiids), deposit feeders (amphipods 

and other crustaceans), small planktivores (Pacific herring [Clupea pallasii], northern anchovy 

[Engraulis mordax], Pacific sardine [Sardinops sagax]), and phytoplankton. Large zooplankton 

such as euphausiids were particularly important, and were consumed by large planktivores, 

cephalopods, small planktivores, shallow large rockfish, canary rockfish, Pacific hake, deep 

vertical migrators, small demersal sharks, and midwater rockfish. The species-level analysis of 

fish predators yielded similar prey groups, with shrimp replacing phytoplankton as the fourth 

most utilized prey resource. 

The PSI analysis identified both intuitive and novel overlaps in diet composition. We 

generally calculated high overlap when comparing species within functional groups and 

functional groups within guilds. One intuitive interaction is among Chinook salmon, albacore 

tuna, migrating seabirds, surface seabirds, and diving seabirds, all of which compete for small 

planktivorous fish prey. Similarly, we calculated high PSI for functional groups that fed 

primarily on euphausiids, cephalopods, or deposit feeders such as amphipods and snails. A diet 

overlap that may be somewhat unexpected was between baleen whales and shallow small 

rockfish. Gray whales (Eschrichtius robustus), which compose the majority of the baleen whale 

functional group biomass, scour the bottom to prey on deposit feeders. In addition, both baleen 

whales and shallow small rockfish prey heavily on euphausiids and other large zooplankton. 

The species-level cluster analysis, PSIs, and MANOVA support the aggregation of fish 

species within the California Current into the functional groups considered here and originally 

defined for the Atlantis ecosystem model of Brand et al. (2007). Examples where our analysis of 

diets suggested a substantially different aggregation than our original functional groups were 

primarily cases where life history characteristics or fishery targeting rather than diets had driven 

the original functional group aggregation (e.g., combining the chondrichthyans spotted ratfish 

9
[Hydrolagus colliei] and Pacific dogfish [Squalus acanthias] or aggregating Pacific sanddabs 

with other flatfish such as rex, deepsea, and Dover soles). For a few species (such as Pacific 

viperfish), new diet information from our literature search suggests specific improvements for 

future functional group aggregation. 

As noted above, the California Current food web is particularly dependent on euphausiids 

as a key forage resource. This may imply substantial impacts of climate change on this food 

web. Current projections of CO2 emissions and atmospheric modeling suggest declines in pH of 

ocean water of 0.14–0.35 by 2100 (IPCC 2007) that could lead to decreased shell calcification 

rates and increased mortality for arthropods such as euphausiids. However, Fabry et al. (2008) 

suggest that the effect of acidification on euphausiids is unknown, though Yamada and Ikeda 

(1999) found increased mortality with prolonged exposure to very low pH (<7.6). Other 

calcifying groups likely to decline under acidification include bivalves, sea urchins, brittle stars, 

and pteropods (Fabry et al. 2008), and predators of these would either switch to alternate prey or 

themselves decline in abundance or weight-at-age.

The diet summaries presented here are primarily derived from data from the 1970s to 

present. However, diets are likely to change with fluctuations in predator and prey abundance. 

For instance, northward range expansions in fish have been documented in the North Sea (Perry 

et al. 2005), and similar range expansions of subtropical species may occur in the California 

Current as water temperatures rise. For instance, Humboldt squid (Dosidicus gigas) once 

common off Baja California, Mexico, migrated as far north as British Columbia during warm El 

Niño periods and established themselves in those ranges thereafter (Field et al. 2007, Zeidberg 

and Robison 2007). This may drastically change the food web by introducing new competitive 

and predatory interactions. Field et al. (2007) suggest that Pacific hake, rockfish, and 

cephalopods are the three dominant prey items of Humboldt squid, and that the high productivity 

and consumption rates makes this predator’s impacts particularly strong.

In conclusion, the diet summaries presented here can serve as the backbone of a range of 

analyses meant to support EBM and modeling. Stock assessment authors and managers setting 

allowable biological catches may consult the diet tables and figures, cluster diagrams of feeding 

guilds, or PSIs to identify impacts of harvest decisions in the food web context of the California 

Current. The diet data can be used at a range of levels, ranging from qualitative descriptions of 

predators and prey of a target species (e.g., Kaplan and Helser 2007) to quantitative modeling of 

tradeoffs in the food web for tactical management decisions (similar to Dorn et al. 2008) or 

strategic scoping of policy options (Kaplan and Levin 2009, Horne et al. in prep). 

10
11

Figures 1–17 and Tables 1–5 
Figure 1. Dendrogram of California Current diets derived from the hierarchical cluster analysis. The 

Height scale is the Euclidian distance created by the distance matrix prior to clustering. Feeding 

guilds A through J, subjectively formed to simplify discussion of results, are delineated. For a 

synopsis of species included in vertebrate and invertebrate groups, see Table 1 and Table 2, 

respectively. For raw diet data, see Figure 2 through Figure 9 and Appendix B. 

12
0% 20% 40% 60% 80% 100%

Deposit feeders

Meiobenthos

Deep vert. migrators

Pacific hake

Canary rockfish

Shallow large rockfish

Small planktivores

Cephalopods

Large planktivores

AABBBBBBB

Percent diet composition

Deposit feeders

Benthic herb. grazers

Megazoobenthos

Cephalopods

Detritus in sediment

Deep vert. migrators

Pacific hake

Small planktivores

Large phytoplankton

Shrimp

Large zooplanton

Mesozooplankton

Figure 2. Percent diet composition of feeding guilds A and B (Figure 1). The feeding guilds were formed 

based on the functional group level hierarchical cluster analysis. The two groups in guild A feed 

almost exclusively on detritus. All groups in guild B prey heavily on large zooplankton. Prey 

taxa making up less than 2% of total diet proportion are excluded from this figure. For species 

names per vertebrate or invertebrate functional group, see Table 1 and Table 2, respectively. 

0% 20% 40% 60% 80% 100%

Transient orcas

Large pelagic

predators

Chinook salmon

Migrating

seabirds

Surface seabirds

Other benthic

filter feeders

Mesozooplankton

Benthic herb.

grazers

Large

zooplankton

CCCCDDDD

Percent diet composition

Deposit feeders

Other benthic filter feeders

Megazoobenthos

Cephalopods

Carrion

Labile detritus

Detritus in sediment

Deep vert. migrators

Deep small rockfish

Deep misc. fishes

Misc. nearshore fish

Deep large rockfish

Midwater rockfish

Pacific hake

Small planktivores

Macroalgae

Pinnipeds

Baleen whales

Small cetaceans

Toothed whales

Large phytoplankton

Small phytoplankton

Gelatinous zooplankton

Large zooplanton

Mesozooplankton

Microzooplankton

Figure 3. Percent diet composition of feeding guilds C and D (Figure 1) from the functional group level 

hierarchical cluster analysis. Functional groups in guild C prey on a mixture of small 

planktivores and zooplankton. Guild D groups feed on a mixture of phytoplankton and 

microzooplankton (dinoflagellates and ciliates). Transient orcas were not assigned to a feeding 

guild because their diet was dissimilar from all other functional groups. Prey taxa making up less 

than 2% of total diet proportion are excluded from this figure. For species names per vertebrate 

or invertebrate functional group, see Table 1 and Table 2, respectively. 

13
0% 20% 40% 60% 80% 100%

Shrimp

Small flatfish

Megazoobenthos

Misc. nearshore

fish

Shallow small

rockfish

Baleen whales

Benthic

carnivores

English sole

EEEEEEEE

Percent diet composition

Benthic carnivores

Deposit feeders

Other benthic filter feeders

Benthic herb. grazers

Deep macrozoobenthos

Megazoobenthos

Labile detritus

Detritus in sediment

Deep vert. migrators

Small planktivores

Shrimp

Large zooplanton

Figure 4. Percent diet composition of feeding guild E (Figure 1) from the functional group level 

hierarchical cluster analysis. All functional groups in this guild largely prey on benthic taxa 

including deposit feeders (amphipods, small crustacea) and other small benthic invertebrates. 

Prey taxa making up less than 2% of total diet proportion are excluded from this figure. For 

species names per vertebrate or invertebrate functional group, see Table 1 and Table 2, 

respectively. 

0% 20% 40% 60% 80% 100%

Shallow

macrozoobenthos

Deep

macrozoobenthos

Sea otters

FFF

Percent diet composition

Deposit feeders

Deep benthic filter feeders

Other benthic filter feeders

Benthic herb. grazers

Deep macrozoobenthos

Megazoobenthos

Labile detritus

Large zooplanton

Figure 5. Percent diet composition of feeding guild F (Figure 1) from the functional group level 

hierarchical cluster analysis. Functional groups in this guild prey on a range of large benthic 

invertebrate taxa including other benthic filter feeders (bivalves) and megazoobenthos (crabs). 

Prey taxa making up less than 2% of total diet proportion are excluded from this figure. For 

species names per vertebrate or invertebrate functional group, see Table 1 and Table 2, 

respectively. 

14
0% 20% 40% 60% 80% 100%

Midwater

rockfish

Small demersal

sharks

Deep benthic

filter feeders

Gelatinous

zooplankton

GGGG

Percent diet composition

Benthic bacteria

Deposit feeders

Other benthic filter feeders

Benthic herb. grazers

Megazoobenthos

Cephalopods

Labile detritus

Deep vert. migrators

Small flatfish

Midwater rockfish

Small planktivores

Large phytoplankton

Small phytoplankton

Shrimp

Small demersal sharks

Gelatinous zooplankton

Large zooplanton

Mesozooplankton

Microzooplankton

Figure 6. Percent diet composition of feeding guild G (Figure 1) from the functional group level 

hierarchical cluster analysis. Functional groups in this guild prey on a variety of zooplankton 

groups including large zooplankton (euphausiids), mesozooplankton (copepods), and gelatinous 

zooplankton (jellyfish). Prey taxa making up less than 2% of total diet proportion are excluded 

from this figure. For species names per vertebrate or invertebrate functional group, see Table 1 

and Table 2, respectively. 

15
0% 20% 40% 60% 80% 100%

Large demersal pred.

Pelagic sharks

Diving seabirds

Large flatfish

Deep large rockfish

Sablefish

Skates and rays

Deep small rockfish

Deep misc. fishes

HHHHHHHHH

Percent diet composition

Benthic carnivores

Deposit feeders

Sh. benthic filter feeders

Benthic herb. grazers

Deep macrozoobenthos

Megazoobenthos

Sh. macrozoobenthos

Meiobenthos

Cephalopods

Carrion

Deep vert. migrators

Shallow small rockfish

Deep small rockfish

Deep misc. fishes

Misc. nearshore fish

Small flatfish

Deep large rockfish

Midwater rockfish

Pacific hake

Large planktivores

Small planktivores

Chinook salmon

Large flatfish

Shrimp

Small demersal sharks

Large zooplanton

Figure 7. Percent diet composition of feeding guild H (Figure 1) from the functional group level 

hierarchical cluster analysis. Guild H contains high trophic level carnivorous functional groups. 

This group can be subdivided into groups specializing in benthic versus pelagic prey. Large 

demersal predators (lingcod), pelagic sharks, diving seabirds, and large flatfish primarily 

consume pelagic prey such as small planktivores and miscellaneous nearshore fish. The 

remaining groups, including skates and rays, deep small rockfish, and deep miscellaneous fishes, 

target benthic prey such as deposit feeders (amphipods and small crustacea), deep miscellaneous 

fishes, and shrimp. Prey taxa making up less than 2% of total diet proportion are excluded from 

this figure. For species names per vertebrate or invertebrate functional group, see Table 1 and 

Table 2, respectively. 

0% 20% 40% 60% 80% 100%

Pinnipeds

Toothed whales

Large demersal

sharks

Small cetaceans

IIII

Percent diet composition

Deposit feeders

Other benthic filter feeders

Megazoobenthos

Cephalopods

Deep vert. migrators

Deep small rockfish

Deep misc. fishes

Misc. nearshore fish

Midwater rockfish

Pacific hake

Large planktivores

Small planktivores

Chinook salmon

Large pelagic predators

Pinnipeds

Shrimp

Small demersal sharks

Skates and rays

Figure 8. Percent diet composition of feeding guild I (Figure 1) from the functional group level 

hierarchical cluster analysis. Functional groups in this guild all prey on cephalopods to some 

degree. Prey taxa making up less than 2% of total diet proportion are excluded from this figure. 

For species names per vertebrate or invertebrate functional group, see Table 1 and Table 2, 

respectively. 

16
0% 20% 40% 60% 80% 100%

Shallow benthic

filter feeders

Microzooplankton

J J

Percent diet composition

Labile detritus

Large phytoplankton

Small phytoplankton

Mesozooplankton

Microzooplankton

Figure 9. Percent diet composition of feeding guild J (Figure 1) from the functional group level 

hierarchical cluster analysis. Functional groups in this guild eat detritus and microzooplankton 

(dinoflagellates and ciliates). Prey taxa making up less than 2% of total diet proportion are 

excluded from this figure. For species names per vertebrate or invertebrate functional group, see 

Table 1 and Table 2, respectively. 

Figure 10. Visual representation of California Current food web structure. Each node represents a 

functional group, and height of the nodes represents trophic level. Diet linkages are indicated by 

lines. Basal species are indicated by red nodes and top species are indicated by yellow nodes. 

Intermediate species fall somewhere between red and yellow and are indicated by shades of 

orange. Predator linkages to basal species are indicated by yellow lines and predatory linkages to 

other intermediate or top species are indicated by green lines. Loops from a node to itself 

indicate cannibalism. (Image produced with FoodWeb3D, written by R. J. Williams, and 

provided by the Pacific Ecoinformatics and Computational Ecology Laboratory, Berkeley, 

California.)

17
Figure 11. Dendrogram of California Current fish-only diets derived from the hierarchical cluster 

analysis. The Height scale is the Euclidian distance created by the distance matrix prior to 

clustering. Feeding guilds A through H, subjectively formed to simplify discussion of results, are 

delineated. For a synopsis of species included in fish functional groups, see Table 1. For raw 

diet data, see Figure 12 through Figure 16. 

18
0% 20% 40% 60% 80% 100%

Pacific viperfish

Blue lanternfish

Pygmy rockfish

Redstripe rockfish

Canary rockfish

Splitnose rockfish

Pacific hake

Pacific herring

Sharpchin rockfish

Jack mackerel

Northern anchovy

Pacific sardine

Spiny dogfish

California headlightfish

Pacific mackerel

Pacific ocean perch

Darkblotched rockfish

Greenstriped rockfish

AAAAAAAAAAAAAAAAA

Percent diet composition

Deposit feeders

Benthic herb. grazers

Megazoobenthos

Cephalopods

Deep vert. migrators

Juv. deep misc. fishes

Small flatfish

Pacific hake

Juv. Pacific hake

Lg. planktivores

Sm. planktivores

Lg. phytoplankton

Shrimp

Sm. demersal sharks

Gelatinous zooplankton

Lg. zooplankton

Mesozooplankton

Figure 12. Percent diet composition of feeding guild A (Figure 11) from the species-level hierarchical 

cluster analysis. All species contain substantial contributions of zooplankton in their diet. Pacific 

viperfish were not assigned to a feeding guild because their diet was dissimilar from all other 

functional groups. Prey taxa making up less than 2% of total diet proportion are excluded from 

this figure. For predator species names and invertebrate prey functional group taxa, see Table 1 

and Table 2, respectively. 

0% 20% 40% 60% 80% 100%

Blue rockfish

Albacore tuna

Black rockfish

Chinook salmon

Garnet lampfish

Northern lampfish

BBBBCC

Percent diet composition

Deposit feeders

Sh. benthic filter feeders

Megazoobenthos

Cephalopods

Deep vert. migrators

Juv. deep sm. rockfish

Juv. deep lg. rockfish

Juv. midwater rockfish

Juv. Pacific hake

Small planktivores

Juv. Chinook salmon

Mesozooplankton

Figure 13. Percent diet composition of feeding guilds B and C (Figure 11) from the species-level 

hierarchical cluster analysis. Species in guild B feed predominately on small planktivorous fish. 

Feeding guild C species target mesozooplankton (copepods). Prey taxa making up less than 2% 

of total diet proportion are excluded from this figure. For predator species names and prey 

functional group taxa, see Table 1 and Table 2, respectively. 

19
0% 20% 40% 60% 80% 100%

English sole

Rex sole

Deepsea sole

Dover sole

Petrale sole

Bering skate

Big skate

Pacific sanddab

Giant grenadier

Longnose skate

DDDDEEE EEE

Percent diet composition

Benthic carnivores

Deposit feeders

Dp. benthic filter feeders

Other benthic filter feeders

Benthic herb. grazers

Deep macrozoobenthos

Megazoobenthos

Sh. macrozoobenthos

Cephalopods

Deep vert. migrators

Sh. small rockfish

Juv. deep sm. rockfish

Deep misc. fishes

Misc. nearshore fish

Small flatfish

Juv. midwater rockfish

Pacific hake

Large flatfish

Shrimp

Large zooplankton

Figure 14. Percent diet composition of feeding guild D and E (Figure 11) from the species-level 

hierarchical cluster analysis (Figure 9). Guild D contains four species of flatfish feeding on small 

benthic prey such as benthic carnivores (polychaetes) and deposit feeders (small crustacean). 

Guild E primarily feeds on shrimp and small flatfish. Prey taxa making up less than 2% of total 

diet proportion are excluded from this figure. For predator species names and prey functional 

group taxa, see Table 1 and Table 2, respectively. 

0% 20% 40% 60% 80% 100%

Pacific grenadier

Sixgill shark

Sleeper shark

Widow rockfish

Yellowtail rockfish

Northern smoothtongue

Twoline eelpout

Rosethorn rockfish

Rougheye rockfish

F F F GGGGGG

Percent diet Composition

Benthic carnivores

Deposit feeders

Other benthic filter feeders

Sh. benthic filter feeders

Benthic herb. grazers

Megazoobenthos

Cephalopods

Deep vert. migrators

Deep small rockfish

Deep misc. fishes

Misc. nearshore fish

Juv. small flatfish

Pacific hake

Juv. Pacific hake

Juv. sablefish

Small planktivores

Chinook salmon

Large planktivores

Pinnipeds

Shrimp

Small demersal sharks

Gelatinous zooplankton

Large zooplankton

Mesozooplankton

Figure 15. Percent diet composition of feeding guilds F and G (Figure 11) from the species-level 

hierarchical cluster analysis. Species in guild F largely feed on cephalopods (squid) and to a 

lesser degree high trophic level fishes. Guild G species feed on a variety of large zooplankton 

(euphausiids), gelatinous zooplankton (jellyfish), deposit feeders (amphipods), and benthic 

herbivorous grazers (snails, urchins, etc.). Prey taxa making up less than 2% of total diet 

proportion are excluded from this figure. For predator species names and prey functional group 

taxa, see Table 1 and Table 2, respectively. 

20
0% 20% 40% 60% 80% 100%

Spotted ratfish

Longspine thornyhead

Shortspine thornyhead

Lingcod

Soupfin sharks

Yelloweye rockfish

Sablefish

Arrowtooth flounder

Pacific halibut

HHHHHHHHH

Percent diet composition

Benthic carnivores

Deposit feeders

Other benthic filter feeders

Benthic herb. grazers

Deep macrozoobenthos

Megazoobenthos

Cephalopods

Carrion

Deep vert. migrators

Sh. small rockfish

Deep small rockfish

Juv. deep sm. rockfish

Deep misc. fishes

Misc. nearshore fish

Small flatfish

Deep large rockfish

Midwater rockfish

Juv. midwater rockfish

Pacific hake

Juv. Pacific hake

Large planktivores

Small planktivores

Chinook salmon

Large flatfish

Lingcod

Shrimp

Juv. sm. demersal sharks

Large zooplankton

Figure 16. Percent diet composition of feeding guild H (Figure 11) from the species-level hierarchical 

cluster analysis. Species within this guild feed on various fish (e.g., Pacific hake and small 

planktivores) and benthic invertebrates including deposit feeders (amphipods) and 

megazoobenthos (crabs). Prey taxa making up less than 2% of total diet proportion are excluded 

from this figure. For predator species names and prey functional group taxa, see Table 1 and 

Table 2, respectively. 

21
Figure 17. MANOVA plot of the PSI of species-level data. CAP1 and CAP2 are axes that represent diet 

composition from the canonical analysis of principal coordinates. Each symbol on the graph 

represents a predator species and the legend indicates functional groups for those species. Black 

axes radiating from the center represent key prey items that differentiate predator feeding habits. 

Fish prey group 1 includes juvenile rockfish species, shallow large rockfish, and small demersal 

sharks. Fish prey group 2 includes small flatfish, sablefish, and Chinook salmon. Fish prey 

group 3 includes midwater rockfish, juvenile sablefish, deep small rockfish, and large flatfish. 

22
Table 1. Vertebrate species included in the functional group analysis and their respective proportional 

biomass within the functional group. Relative abundances for all fish groups except 

miscellaneous nearshore fish (e.g., sculpin, croakers) are taken from the NWFSC trawl survey 

data, 1998–2003. See Appendix A for seabird and marine mammal relative abundances. 

Functional groups and codes are from Brand et al. (2007), though group compositions may 

change slightly. NA = not available. 

Code Group Common name Scientific name Proportion

SHR Shallow large rockfish Adult Redstripe rockfish Sebastes proriger 0.95

Adult Yelloweye rockfish S. ruberrimus 0.05

Adult Blue rockfish S. mystinus <.01

Juv. Copper rockfish S. caurinus 0.50

Juv. Blue rockfish S. mystinus 0.50

FDP English sole Adult English sole Parophrys vetulus 1.00

Juv. English sole P. vetulus NA

FDC Deep small rockfish Adult Longspine thornyhead Sebastolobus altivelis 0.63

Adult Sharpchin rockfish Sebastes zacentrus 0.20

Adult Splitnose rockfish S. diploproa 0.17

Juv. Splitnose rockfish S. diploproa NA

FDO Deep large rockfish Adult Shortspine thornyhead Sebastolobus alascanus 0.75

Adult Darkblotched rockfish Sebastes crameri 0.24

Adult Rougheye rockfish S. aleutianus 0.01

Juv. Darkblotched rockfish S. crameri 1.00

FPO Canary rockfish Adult Canary rockfish S. pinniger 1.00

Juv. Canary rockfish S. pinniger 1.00

FDS Midwater rockfish Adult Widow rockfish S. entomelas 0.43

Adult Pacific ocean perch S. alutus 0.34

Adult Yellowtail rockfish S. flavidus 0.23

Adult Black rockfish S. melanops <0.01

Juv. Chilipepper rockfish S. goodei 0.64

Juv. Yellowtail rockfish S. flavidus 0.22

Juv. Widow rockfish S. entomelas 0.12

Juv. Bocaccio S. paucispinis 0.03

FDB Shallow small rockfish Adult Rosethorn rockfish S. helvomaculatus 0.71

Adult Greenstriped rockfish S. elongatus 0.24

Adult Pygmy rockfish S. wilsoni 0.06

Juv. Shortbelly rockfish S. jordani 1.00

FDE Misc. nearshore fish Juv. White croaker Genyonemus lineatus NA

Juv. Sculpin Cottidae NA

Juv. Midshipman Porichthys notatus NA

FPL Large planktivores Adult Pacific mackerel Scomber japonicus 0.59

Adult Jack mackerel Trachurus symetricus 0.41

Juv. Jack mackerel T. symetricus NA

FPS Small planktivores Adult Northern anchovy Engraulis mordax 0.59

Adult Pacific sardine Sardinops sagax 0.39

Adult Pacific herring Clupea pallasii 0.02

23
Table 1 continued. Vertebrate species included in the functional group analysis and their respective 

proportional biomass within the functional group. Relative abundances for all fish groups except 

miscellaneous nearshore fish (e.g., sculpin, croakers) are taken from the NWFSC trawl survey 

data, 1998–2003. See Appendix A for seabird and marine mammal relative abundances. 

Functional groups and codes are from Brand et al. (2007), though group compositions may 

change slightly. NA = not available. 

Code Group Common name Scientific name Proportion

FPS Small planktivores 

(continued) 

Juv. Pacific herring C. pallasii NA

FVD Large flatfish Adult Arrowtooth flounder Atheresthes stomias 0.71

Adult Pacific halibut Hippoglossus stenolepis 0.15

Adult Petrale sole Eopsetta jordani 0.14

Juv. Arrowtooth flounder Atheresthes stomias 0.83

Juv. Pacific halibut Hippoglossus stenolepis 0.17

FVB Chinook salmon Adult Chinook salmon Oncorhynchus 

tshawytscha 

1.00

Juv. Chinook salmon O. tshawytscha 1.00

FDD Deep misc. fishes Adult Pacific grenadier Coryphaenoides acrolepis 0.49

Adult Giant grenadier Albatrossia pectoralis 0.38

Adult 

Adult 

Misc. fishes 

 California 

 smoothtongue 

 Twoline eelpout 

Bathylagus stilbius 

Bothrocara brunneum 

0.13

Juv. Pacific grenadier Coryphaenoides acrolepis 0.57

Juv. Giant grenadier Albatrossia pectoralis 0.43

SHP Pelagic sharks Adult Soupfin shark Galeorhinus galeus 1.00

Juv. Soupfin shark G. galeus NA

SSK Skates and rays Adult Longnose skate Raja rhina 0.80

Adult Bering skate Bathyraja interrupta 0.16

Adult Big skate Raja binoculata 0.04

Juv. Big skate R. binoculata NA

SHD Large demersal sharks Adult Sleeper shark Somniosus pacificus 0.97

Adult Sixgill shark Hexanchus griseus 0.03

Juv. Sixgill shark H. griseus NA

FVS Large demersal predators Adult Lingcod Ophiodon elongatus 1.00

Juv. Lingcod O. elongatus 1.00

FMN Sablefish Adult Sablefish Anoplopoma fimbria 1.00

Juv. Sablefish A. fimbria 1.00

FMM Pacific hake Adult Pacific hake Merluccius productus 1.00

Juv. Pacific hake M. productus 1.00

FDF Small flatfish Adult Dover sole Microstomus pacificus 0.76

Adult Rex sole Glyptocephalus zachirus 0.14

Adult Pacific sanddab Citharichthys sordidus 0.08

Adult Deepsea sole Embassichthys bathybius 0.02

Juv. Deepsea sole E. bathybius NA

24
Table 1 continued. Vertebrate species included in the functional group analysis and their respective 

proportional biomass within the functional group. Relative abundances for all fish groups except 

miscellaneous nearshore fish (e.g., sculpin, croakers) are taken from the NWFSC trawl survey 

data, 1998–2003. See Appendix A for seabird and marine mammal relative abundances. 

Functional groups and codes are from Brand et al. (2007), though group compositions may 

change slightly. NA = not available. 

Code Group Common name Scientific name Proportion

FBP Deep vertical migrators Misc. myctophids 0.38

Adult Blue lanternfish Tarletonbeania crenularis 

Adult California Diaphus theta 

 headlightfish 

Adult Pacific viperfish Chauliodus macouni 0.26

Adult Northern lampfish Stenobrachius leucopsarus 0.18

Adult Garnet lanternfish S. nannochir 0.18

FBP Deep vertical migrators Juv. Pacific viperfish Chauliodus macouni 0.26

FVT Large pelagic predators Adult Albacore tuna Thunnus alalunga 1.00

Juv. Albacore tuna T. alalunga NA

SHB Small demersal sharks Adult Spiny dogfish Squalus acanthias 0.81

Adult Spotted ratfish Hydrolagus colliei 0.19

Juv. Spiny dogfish Squalus acanthias 1.00

FVO Migrating seabirds Adult Black-footed albatross Phoebastria nigripes 0.06

Adult and Laysan albatross P. immutabilis 

Adult Black-legged 

kittiwake 

Rissa tridactyla 0.02

Adult Northern fulmar Fulmarus glacialis 0.03

Adult Sooty shearwater Puffinus griseus 0.90

Juv. Sooty shearwater P. griseus NA

SP Diving seabirds Adult Cormorants, shags Phalacrocoracidae 0.16

Adult Pigeon guillemot Cepphus columba 0.00

Adult Rhinoceros auklet Cerorhinca monocerata 0.19

Adult Cassin’s auklet Ptychoramphus aleuticus 0.01

Adult Common murre Uria aalge 0.59

Adult Ancient murrelet Synthliboramphus 0.01

and antiquus 

Adult Marbled murrelet Brachyramphus 

marmoratus 

Adult Tufted puffin Fratercula cirrhata 0.03

Juv. Tufted puffin F. cirrhata NA

SB Surface seabirds Adult Western gull Larus occidentalis 0.94

Adult Storm petrel Hydrobatidae 0.06

Juv. Storm petrel Hydrobatidae NA

WHB Baleen whales Adult Gray whale Eschrichtius robustus 0.62

Adult Humpback whale Megaptera novaeangliae 0.05

Adult Blue whale Balaenopter musculus 0.15

Adult Fin whale B. physalus 0.18

Juv. Fin whale B. physalus NA

25
Table 1 continued. Vertebrate species included in the functional group analysis and their respective 

proportional biomass within the functional group. Relative abundances for all fish groups except 

miscellaneous nearshore fish (e.g., sculpin, croakers) are taken from the NWFSC trawl survey 

data, 1998–2003. See Appendix A for seabird and marine mammal relative abundances. 

Functional groups and codes are from Brand et al. (2007) though group compositions may change 

slightly. NA = not available. 

Code Group Common name Scientific name Proportion

WHT Toothed whales Adult Resident orcas Orcinus orca 0.03

Adult Baird’s beaked whale Berardius bairdii 0.07

Adult Cuvier’s beaked whale Ziphius cavirostris 0.17

Adult Mesoplodon beaked 

whales 

Mesoplodon spp. 0.05

Adult Short-finned pilot 

whale 

Globicephala 

macrorhynchus 

0.00

Adult Sperm whale Physeter macrocephalus 0.68

WHT Toothed whales Juv. Sperm whale P. macrocephalus NA

REP Transient orcas Adult Transient orca Orcinus orca 1.00

Juv. Transient orca O. orca NA

WHS Small cetaceans Adult Dall’s porpoise Phocoenoides dalli 0.20

Adult Harbor porpoise Phocoena phocoena 0.07

Adult Short-beaked common 

dolphin 

Delphinus delphis 0.31

Adult Bottlenose dolphin Tursiops truncatus 0.03

Adult Striped dolphin Stenella coeruleoalba 0.05

Adult Risso’s dolphin Grampus griseus 0.12

Adult N. right whale dolphin Lissodelphis borealis 0.07

Adult Pacific white-sided 

dolphin 

Lagenorhynchus 

obliquidens 

0.15

Juv. Pacific white-sided 

dolphin 

L. obliquidens NA

PIN Pinnipeds Adult California sea lion Zalophus californianus 0.27

Adult Steller sea lion Eumetopias jubatus 0.02

Adult Harbor seal Phoca vitulina 0.15

Adult N. elephant seal Mirounga angustirostris 0.32

Adult N. fur seal Callorhinus ursinus 0.25

Juv. N. elephant seal Mirounga angustirostris 0.38

Juv. California sea lion Zalophus californianus 0.31

Juv. N. fur seal Callorhinus ursinus 0.29

Juv. Steller sea lion Eumetopias jubatus 0.02

WDG Sea otters Adult Sea otter Enhydra lutris 1.00

Juv. Sea otter E. lutris NA

26
Table 2. Invertebrate taxa included in each functional group. Functional groups and codes are from 

Brand et al. (2007). 

Code Group Species 

BB Benthic bacteria Not identified 

BC Benthic carnivores Polychaetes, nematodes, burrowing crustacea, peanut worms 

(Sipuncula), flatworms 

BD Deposit feeders Amphipods, isopods, small crustacea, snails, ghost shrimp 

(Thalassinidea), sea cucumbers (Holothuroidea), worms, sea 

mouse (polychaete worm), sea slugs, barnacles, solenogaster 

(Aplacophora), hermit crabs 

BFD Deep benthic filter feeders Anemones, deep corals, lampshells, reticulate sea anemone 

(Actinauge verrilli), rough purple sea anemone 

(Paractinostola faeculenta), swimming sea anemone 

(Stomphia coccinea), gigantic sea anemone (Metridium 

farcimen), corals, sponges 

BFF Other benthic filter feeders Geoduck (Panopea abrupta), barnacles, razor clam (Siliqua

patula), littleneck clam (Venerupis philippinarum), Manila 

clam (Ruditapes philippinarum), miscellaneous bivalves, 

Vancouver scallop (Delectopecten vancouverensis), glass 

scallop (Cyclopecten davidsoni), green sea urchin 

(Strongylocentrotus droebachiensis), red sea urchin 

(Strongylocentrotus franciscanus)

BFS Shallow benthic filter feeders Barnacles, seafans, soft corals, gorgonian corals, black 

corals, green colonial tunicate (Didenmum molle), sea pens, 

sea whips, sea potatoes, vase sponge (Leucandra heathi), 

mussels, scallops 

BG Benthic herbivorous grazers Snails, abalone (Haliotis spp.), nudibranchs, sand dollars, 

naked solarelle (Solariella nuda), dorid nudibranchs, limpets, 

heart sea urchin (echinoderm), spot prawns, pandalid 

shrimps 

CEP Cephalopods Market squid (Loligo opalescens), Japetella spp., armhook 

squids (Gonatus spp.), Chiroteuthis spp., Abraliopsis spp., 

robust clubhook squid (Moroteuthis robusta), rhomboid 

squid (Thysanoteuthis rhombus), sandpaper squid (Cranchia 

scabra), vampire squid (Vampyroteuthis infernalis) 

DC Carrion — 

DL Labile detritus — 

BMD Deep macrozoobenthos Sea stars, moonsnail (Naticidae), whelks, leather sea star 

(Dermasterias imbricata), bat star (Asterina miniata), 

sunflower sea star (Pycnopodia helianthoides), common mud 

star (Ctenodiscus crispatus), crinoids, brittlestars, basketstar 

(Gorgonocephalus eucnemis) 

DR Refractory detritus — 

MA Macroalgae Kelp 

BO Meiobenthos Flagellates, ciliates, nematodes 

27
28

Table 2 continued. Invertebrate taxa included in each functional group. Functional groups and codes are 

from Brand et al. (2007). 

Code Group Species 

BML Megazoobenthos Dungeness crab (Cancer magister), tanner crab 

(Chionoecetes bairdi), spiny lobster (Panulirus interruptus), 

pinchbug crabs, red rock crab (Cancer productus), graceful 

rock crab (Cancer gracilis), spider crabs, grooved tanner 

crab (Chionoecetes tanneri), bairdi, scarlet king crab 

(Lithodes couesi), California king crab (Paralithodes 

californiensis) 

PL Large phytoplankton Diatoms 

PS Small phytoplankton Microphytoplankton 

PWN Shrimp Crangon and mysid shrimps 

BMS Shallow macrozoobenthos Giant Pacific octopus (Enteroctopus dofleini), north Pacific 

bigeye octopus (Octopus californicus), yellowring octopus 

(Japetella heathi), smoothskin octopus (Benthoctopus 

leioderma), flapjack devilfish (Opisthosteuthis californiana) 

ZG Gelatinous zooplankton Salps, jellyfish, ctenophores, comb jellies 

ZL Large zooplankton Euphausiids, chaetognaths, pelagic shrimps, pelagic 

polychaetes, pasiphaeids 

ZM Mesozooplankton Copepods, cladocera 

ZS Microzooplankton Ciliates, dinoflagellates, nanoflagellates, gymnodinoids, 

protozoa 
Table 3. PSI of California Current functional groups. Significant diet overlaps (>60%) are shaded in gray. 

Group 

Benthic detritivores 

Meiobenthos 

Deep vertical migrators 

Pacific hake 

Canary rockfish 

Shallow large rockfish 

Small planktivores 

Cephalopods 

Large planktivores 

Transient orca 

Albacore tuna 

Chinook salmon 

Migrating seabirds 

Surface seabirds 

Other benthic filter feeders 

Mesozooplankton 

Benthic herb. grazers 

Large zooplankton 

Shrimp 

Small flatfish 

Megazoobenthos 

Misc. nearshore fish 

Shallow small rockfish 

Baleen whales 

Benthic detritivores X Meiobenthos 82 X 

Deep vertical migrators 

5 0 X 

Pacific hake 0 0 41 X 

Canary rockfish 0 0 43 80 X 

Sh. large rockfish 0 0 42 81 95 

X

Small planktivores 18 0 49 63 63 62

X

Cephalopods 5 0 51 72 73 72 72

29

X

Large planktivores 5 0 49 64 61 63 71 78

X

Transient orc a 0 0 0 0 0 0 0 0 0X

Albacore tuna 0 0 11 23 6 6 3 11 10 0 X

Chinook salmon 0 0 26 46 27 28 26 32 36 0 58

X

Migrating seabirds 0 0 16 24 6 5 4 7 13 0 70 66

X

Surface seabirds 0 0 6 26 7 9 6 9 16 0 60 73 74

X

4 0 0 0 0 0 5 0 0 0 0 0 0 0X

60000000

Other benthic filter feeders 

1 2

Mesozooplankton 14 0 0 0 0 0 2 70 X 

Benthic herb. grazers 

3 4000006000000050

0 0 4 0 0 1 1 6 1 0 5 0 0 3 5 0 0 1X

h 0 0 8 6 6 5 6 6 9 0 9 7 4 6 0 0 0 5 9X

5 8 4 0 0 1 9 5X

0 0 4 0 0 1 3 7 4 0 5 3 0 2 0 0 0 1 9 8 8X

2 2 2 4 X 

Large zooplankton 

p

18 0 23 14 14 15 49 21 24 0 4 14 3 9 32 47 56 

X

Shrim 2Small flatfis 1 5Megazoobenthos 0 0 4 6 2 4 4 12 9 0 9 5 4 5

Misc. nearshore fish 

1 1 5 5 5
Table 3 continued vertically. PSI of California Current functional groups. Significant diet overlaps (>60%) are shaded in g

Group 

Benthic detritivores 

Meiobenthos 

Deep vertical migrators 

Pacific hake 

Canary rockfish 

Shallow large rockfish 

Small planktivores 

Cephalopods 

Large planktivores 

Transient orca 

Albacore tuna 

Chinook salmon 

Migrating seabirds 

Surface seabirds 

Other benthic filter feeders 

Mesozooplankton 

Benthic herb. grazers 

Large zooplankton 

Shrimp 

Small flatfish 

Megazoobenthos 

Misc. nearshore fish 

Shallow small rockfish 

Baleen whales 

Sh. small rockfish 1 0 1 9 2 9 1 9 2 0 3 9 3 8 0 0 0 7 5 2 6 6X 4 2 3 2 3 3 3 1 2 1 1 3 4 3 3Baleen whales 0 0 40 41 36 38 36 41 39 0 14 32 9 12 0 0 0 15 38 42 38 40 63 X

Benthic carnivore 

e

s 0 0 4 0 0 1 0 4 0 0 5 0 0 0 0 0 0 1 8 8 4 0 4 

0041314350520200018

2 2 2 3 3 3 4 3 5

English sol 1 5 63 43 58 40 5Shallow macrozoobenthos 0 0 4 1 2 1 2 4 4 0 6 3 0 2 0 0 0 1 3 4 7 4 6 

r 0 0 0 1 3 0 2 2 4 0 1 3 0 2 0 0 0 0 0 2 7 6 7 

1 2 2 2 4 1 1 

Deep macrozoobenthos 0 0 20 20 20 20 20 20 20 0 3 20 3 8 20 0 0 14 30 9 34 20 20 2

Sea otte 

301 1 1 3 3 2 

Midwater rockfish 0 0 48 48 41 41 38 47 47 0 25 45 29 29 0 0 0 17 6 11 13 5 43 4

Small demersal sharks 

0 0 42 47 43 47 46 58 60 0 3 7 6 4 0 7 7 6 3 1 1 

8013337930363988550400900194528102158000113805

s 00001303002976000010601

1 3 1 2 0 0 1 1 1 2 3 4 

Deep benthic filter feeders 

18 0 26 14 14 15 38 24 23 0 8 14 3 6 43 29 14 50 29 18 18 14 30 2

Gelatinous zooplankton 

1 4 3 3 3 5 3 4 2 4 4 1 5 2 3 

Large demersal predators 

1 1 2 2 2

Pelagic shark 2 1 3 3 4 4

Diving seabirds 0 0 16 29 11 12 9 12 19 0 48 59 64 66 000814607

s 20624364102347000452663

1 1

Large flatfish 0 0 14 24 14 14 14 28 27 0 22 26 27 27 0 0 0 11 5 13 17 12 23 2

Deep large rockfish 1 0 15 11 13 11 13 28 22 0 13 25 23 28 0 0 0 10 11 21 15 31 33 1

Sablefish 0 0 9 10 6 7 5 13 17 0 20 25 32 36 0 0 0 5 9 13 15 8 15 1

Skates and rays 0 0 13 8 9 8 9 19 31 0 18 19 25 21 0 0 0 6 7 14 14 18 19 1

Deep small rockfish 

0 0 27 21 14 14 13 28 23 0 26 30 36 30 0 0 0 12 35 48 41 47 53 4

Deep misc. fishe 2 1 1 1 1 2 3 1 1 1 1 2 3 2 3 4 3 
Table 3 continued vertically. PSI of California Current functional groups. Significant diet overlaps (>60%) are shaded in g

Group 

Benthic detritivores 

Meiobenthos 

Deep vert. migrators 

Pacific hake 

Canary rockfish 

Shallow large rockfish 

Small planktivores 

Cephalopods 

Large planktivores 

Transient orca 

Albacore tuna 

Chinook salmon 

Migrating seabirds 

Surface seabirds 

Other benthic filter feeders 

Mesozooplankton 

Benthic herb. grazers 

Large zooplankton 

Shrimp 

Small flatfish 

Megazoobenthos 

Misc. nearshore fish 

Shallow small rockfish 

Baleen whales 

Pinniped s 00041203900071000000501

1 2 3 3 4

Toothed whale s 00032309105138000137662

00010038865419000068812

36763

80800096800000

1 1 1 1 2 1 1

Large demersal sharks 

1 1 1 1 1

Small cetaceans 0 0 19 9 3 3 0 9 10 0 20 17 36 27 0 0 0 1 1

Shallow benthic filter feeders 

1 2 65 4 00750401

000000000

2 4 3 

Microzooplankton 0 0 0 0 0 67 4 20750400

3 

31
32

Table 3 continued horizontally. PSI of California Current functional groups. Significant diet overlaps (>60%) are shaded ilist on this page repeats last 19 items from same list of previous two pages of this table. 

Group 

Midwater rockfish 

Small demersal sharks 

Deep benthic filter feeders 

Gelatinous zooplankton 

Large demersal predators 

Pelagic sharks 

Diving seabirds 

Large flatfish 

Deep large rockfish 

Sablefish 

Skates and rays 

Deep small rockfish 

Deep misc. fishes 

Pinnipeds 

Toothed whales 

Large demersal sharks 

Small cetaceans 

Shallow benthic filter feeders 

Microzooplankton 

Midwater rockfish XSmall demersal sharks 5 2 X

Deep benthic filter feeders 1 9 5X 1 

Gelatinous zooplankton 36 36 57 X 

Large demersal predators 24 30 1 1 X 

Pelagic sharks 21 15 0 0 51 X 

Diving seabirds 37 25 8 8 37 51 X 

Large flatfish 33 36 14 10 33 32 34 X 

Deep large rockfish 27 31 19 9 23 16 21 36 X 

Sablefish 27 24 10 4 31 30 30 36 47 X 

Skates and rays 26 32 12 5 33 17 30 38 36 39 X 

Deep small rockfish 38 33 25 11 14 17 35 32 43 35 27 X 

Deep misc. fishes 25 17 27 13 2 0 17 23 31 21 42 48 X 

Pinnipeds 19 19 0 0 35 41 34 25 19 34 15 20 0 X 

Toothed whales 18 15 3 0 14 18 26 16 16 24 21 27 16 58 X 

Large demersal sharks 3 16 0 0 12 13 12 8 13 22 13 14 4 46 49 X 

Small cetaceans 24 16 3 0 28 36 39 27 15 26 18 36 13 50 61 44 X 

Shallow benthic filter feeders 

0 0 57 49 0 0 0 0 1 0 0 0 2 0 0 0 0 X 

Microzooplankton 0 0 29 32 0 0 0 0 0 0 0 0 0 0 0 0 0 57 X 
Table 4. Comparison of our California Current food web to other marine food webs from Dunne et al. 

(2004), using common food web structure properties including: taxa (the number of species), s 

(the number of lumped trophic species), c (connectance [C=L/S2]), links per species (L/S), 

percent top species (%T), percent intermediate species (%I), percent basal species (%B), percent 

cannibalistic species (%Can), and percent omnivorous species (%Omn). 

Food web Taxa S C L/S %T %I %B %Can %Omn Source 

California Current * 49 0.23 11.3 4 83 14 39 37 This study 

Other marine food webs 

 Benguela Current 29 29 0.24 7.0 0 93 7 24 76 Yodzis 1998 

 Caribbean reef small 50 50 0.22 11.1 0 94 6 42 86 Opitz 1996 

 Northeast U.S. shelf 81 79 0.22 17.8 4 94 3 32 78 Link 2002 

 Caribbean reef large 249 245 0.05 13.8 0 98 2 4 87 Opitz 1996 

*The number of species which contributed to this study is unknown due to the aggregation of prey into functional 

groups; however, we estimate the total to be approximately 200 (±50) species. 

33
Table 5. PSI for all fish species diets. The borders outline comparisons of species within functional groups. Significant di

shaded in gray. Table is continued vertically on next page, then horizontally on third page to encompass all functio

Group Species 

Redstripe rockfish 

Yelloweye rockfish 

Blue rockfish 

English sole 

Longspine thornyhead 

Sharpchin rockfish 

Splitnose rockfish 

Shortspine thornyhead 

Darkblotched rockfish 

Rougheye rockfish 

Canary rockfish 

Widow rockfish 

Pacific ocean perch 

Yellowtail rockfish 

Black rockfish 

Rosethorn rockfish 

Greenstriped rockfish 

Pygmy rockfish 

Pacific mackerel 

Jack mackerel 

Sh. large rockfis h Redstripe rockfis h X

Yelloweye rockfis h 1XBlue rockfi sh 6 7X 3 

English sole English sole 1 23 4 X Deep small rockfish Longspine thornyhead 2 35 19 34 X 

Sharpchin rockfish 45 16 10 16 24 X 

Splitnose rockfish 95 2 8 2 7 50 X 

Deep large rockfish Shortspine thornyhead 1 24 4 18 44 14 3 X 

Darkblotched rockfish 79 6 9 6 15 64 84 6 X

Rougheye rockfish 9 29 19 17 32 25 14 26 18 X 

Canary rockfish Canary rockfish 95 3 8 3 5 50 97 4 80 1 

34

4 X

Midwater rockfish Widow rockfish 35 7 9 6 14 45 40 11 43 19 37 X 

Pacific ocean perch 65 14 10 12 22 74 70 15 82 28 69 4 4 XYellowtail rockfish 41 10 15 2 20 48 44 12 45 26 44 68 4 9 XBlack rockfish 16 39 50 5 20 19 18 9 19 24 16 23 19 27 X 

Sh. small rockfish Rosethorn rockfish 7 29 10 52 35 32 12 23 21 55 12 17 28 15 11 X 

Greenstriped rockfish 73 12 10 13 22 71 78 13 90 26 77 44 90 48 20 26 X Pygmy rockfish 92 2 8 3 4 49 94 2 85 11 92 37 67 41 18 11 75 X

Large planktivores Pacific mackerel 63 2 7 2 6 49 63 5 67 13 63 43 66 51 27 10 66 69 X

Jack mackerel 57 9 13 3 10 46 57 4 57 28 58 37 58 51 28 8 58 57 60 X 

Small planktivores Northern anchovy 66 2 7 5 4 48 65 4 66 14 68 34 67 42 19 10 69 66 64 61 

Pacific sardine 55 0 6 2 3 47 54 1 58 10 54 34 54 40 17 8 56 60 69 56 7

Pacific herring 81 7 9 8 10 53 82 8 87 24 81 40 71 42 25 14 80 86 68 67 6

Large flatfish Arrowtooth flounder 15 33 24 7 23 20 16 15 15 34 18 18 23 25 33 17 20 15 17 24 1

Halibut 1 30 7 24 49 15 3 35 7 21 3 8 13 7 9 24 13 3 3 6 Petrale sole 1 21 2 4 3 2 1 4 1 16 0 2 2 1 6 2 3 1 2 27 
Table 5 continued vertically. PSI for all fish species diets. Significant diet overlaps (>60%) are shaded in gray. 

Group Species 

Redstripe rockfish 

Yelloweye rockfish 

Blue rockfish 

English sole 

Longspine thornyhead 

Sharpchin rockfish 

Splitnose rockfish 

Shortspine thornyhead 

Darkblotched rockfish 

Rougheye rockfish 

Canary rockfish 

Widow rockfish 

Pacific ocean perch 

Yellowtail rockfish 

Black rockfish 

Rosethorn rockfish 

Greenstriped rockfish 

Pygmy rockfish 

Pacific mackerel 

Jack mackerel 

Chinook salmon Chinook salmon 27 40 41 0 21 27 27 1 26 23 27 29 29 40 69 8 8 6 3 6 

2 2 3 3 

Deep misc. fishes Pacific grenadier 2 20 4 39 45 15 4 24 8 20 2 9 13 7 8 28 13 5 7 5 

Giant grenadier 16 16 10 17 27 30 18 22 21 35 17 21 28 22 22 22 27 18 20 46 

Northern smoothtongue 21 20 9 28 31 36 23 10 30 18 21 33 29 28 19 33 30 29 39 21 

Twoline eelpout 38 20 9 37 32 50 39 19 43 22 37 40 48 42 19 44 47 39 41 37 

Pelagic sharks Soupfin shark 1 46 26 0 23 1 0 8 0 17 0 2 6 12 27 0 1 0 3 7 

Skates and rays Longnose skate 7 27 10 12 25 22 12 22 17 37 10 18 24 20 17 22 23 9 12 31 

Bering skate 13046007040000411010

09060135002030

1 1 3 

Big skate 1 13 0 4 23 0 0 27 0 14 0 0 0 0 4 1 1 0 1 30 

Dp. demersal sharks Sleeper shark 0 1 0 8 14 1 0 14 0 10 0 1 2 5 3 2 3 0 4 3 

Sixgill shark 1 1 0 1 12 1 

Lingcod Lingcod 1 39 8

35 3 11 5 1 5 1 15 4 4 6 11 10 5 5 1 4 10 

Sablefish Sablefish 4 18 12 9 38 14 7 36 10 24 6 12 14 17 13 14 15 6 9 10 

Pacific hake Pacific hake 79 21 26 1 17 46 79 3 79 19 80 36 66 49 36 8 74 79 63 65 

Small flatfish Dover sole 1 12 4 34 23 13 3 13 6 12 3 7 11 3 4 13 12 3 1 1 

Rex sole 1 19 3 49 29 12 2 10 6 9 0 6 8 0 3 32 8 2 1 0 

Pacific sanddab 1 28 4 39 31 16 2 24 6 45 3 6 14 2 7 49 12 3 2 31 

Deepsea sole 1 18 4 36 28 14 2 13 6 11 2 6 11 2 4 18 11 2 1 1 

Deep vert. migrators Blue lanternfish 95 393505 97 3 84 12 95 37 67 41 19 11 76 97 65 57 

California headlightfish 67 12 9 2 3 8 1 1 5 68 10 76 17 66 39 73 41 19 20 75 74 78 57 

Pacific viperfis h 10008630232465074000

h 04969615839530924750

3 1 1 1

Northern lampfish 29 19 9 22 23 42 30 10 38 17 28 33 36 28 19 30 37 36 43 28 

Garnet lanternfis 2 2 2 2 1 1 2 2 2 1 1 2 2 3 2 

Albacore tuna Albacore tuna 3 39 41 5 29 12 8 9 11 24 5 13 15 18 57 12 13 5 7 10 

Sm. demersal sharks Spiny dogfish 53 15 9 3 18 47 53 8 53 21 53 40 55 53 22 10 56 53 60 59 

Spotted ratfish 1 19 3 13 28 6 2 41 6 21 0 5 6 0 8 7 7 2 1 10 
36

Table 5 continued horizontally. PSI for all fish species diets. The borders outline comparisons of species within functiona

diet overlaps (>60%) are shaded in gray. Group column list on this page is repeated from previous page and this p

columns to the right. 

Group Species 

Chinook salmon 

Pacific grenadier 

Giant grenadier 

Northern smoothtongue 

Twoline eelpout 

Soupfin shark 

Longnose skate 

Bering skate 

Big skate 

Sleeper shark 

Sixgill shark 

Lg. demersal pred. 

Sablefish 

Pacific hake 

Dover sole 

Rex sole 

Pacific sanddab 

Deepsea sole 

Blue lanternfish 

California headlightfish 

Chinook salmon Chinook salmon X Deep misc. fishes Pacific grenadier 7 X

Giant grenadier 21 48 XNorthern smoothtongue 21 30 29 XTwoline eelpout 31 52 54 44 X

Pelagic sharks Soupfin shark 31 6 5 0 5XSkates and rays Longnose skate 20 27 52 15 28 14 X

Bering skate 0 5 37 0 0 1 34 X

Big skate 0 9 41 0 4 2 38 79 X

Dp. demersal sharks Sleeper shark 5 40 10 0 5 13 9 6 6 X

Sixgill sharks 6 47 19 0 16 17 20 0 4 48 X

Lg. demersal pred . d Lingco 2 1 3 5 1 3 3 8 8 8 7 1X 4 3 1Sablefish Sablefish 14 26 25 12 22 29 37 4 8 21 28 24 X Pacific hak e Pacific hak e 4 6 2 7 1 7 0 9 0 0 0 0 9 0X 1 2 3 2 1 Small flatfis h Dover sol e 1 1 3 6 1 0 0 1 1 6 1 3 0 2X 2 1 1 1 1 1 

Rex so le 0 4 3 7 2 0 8 0 0 1 1 0 7 0 5X 3 1 2 3 5Pacific sanddab 1 35 52 28 24 0 31 42 42 3 0 4 9 2 21 32 XDeepsea so le 06615001110391 2 1 2 1 1 74 74 27 X

Deep vert. migrator s Blue lanternfis h 6586000000016 2 1 2 4 1 78 3 3 3 3X

California headlightfis h 6470905000010 2 1 2 5 4 1 1 66 10 12 12 12 72 XPacific viperfis h 0 0 0 0 0 0 5 0 0 0 0 0 1 0 0 0 0 0 0 0Northern lampfish 26 24 28 60 5005000010802253 1 1 2 1 2 2 1 3 62 Garnet lanternfis h 98963010000180766756

1 1 4 2 1 2 2 4 

Albacore tun a Albacore tun a 6 1 1 8 1 2 6 1 1 5 4 0 0 3 6 5 5 5 6 8 

5 1 1 1 3 1 1 2 2 

Sm. demersal sharks Spiny dogfish 37 11 22 24 42 15 30 16 17 9 21 20 23 56 2 0 2 1 53 53 

Spotted ratfish 0 12 16 6 7 8 31 25 43 11 5 15 15 1 13 7 15 6 3 6 
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Biol. Ecol. 46:62–67. 

Yang, M. 1994. Food habits and diet overlap of arrowtooth flounder (Atheresthes stomias) and Pacific 

halibut (Hippoglossus stenolepis) in the Gulf of Alaska. In International Symposium on North 

Pacific Flatfish, p. 205–223. Alaska Sea Grant College Program, Anchorage. 

Yang, M. S., and M. W. Nelson. 2000. Food habits of the commercially important groundfishes in the 

Gulf of Alaska in 1990, 1993, and 1996. U.S. Dept. Commer., NOAA Tech. Memo. NMFSAFSC-112. 

Yodzis, P. 1998. Local trophodynamics and the interaction of marine mammals and fisheries in the 

Benguela ecosystem. J. Anim. Ecol. 67:635–658. 

York, K. J. 2005. Resource partitioning in an assemblage of deepwater, demersal rockfish (Sebastes

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Zeidberg, L. D., and B. H. Robison. 2007. Invasive range expansion by the Humboldt squid, Dosidicus 

gigas, in the eastern North Pacific. Proc. Natl. Acad. Sci. USA 104(31):12948–12950. 

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45

Appendix A: Sources for Diets 

Below are summaries of the publications that contributed to each species’ diet and 

subsequently each functional group’s diet. Two or three letter abbreviations for each functional 

group are listed for consistency with Brand et al. (2007). The species that comprise each 

functional group are listed in the first sentence of each summary, with the species ordered from 

most to least abundant by biomass. 

Fish 

Shallow Large Rockfish (SHR) 

Adult shallow large rockfish diets consist of data from redstripe (Sebastes proriger), 

yelloweye (S. ruberrimus), and blue rockfishes (S. mystinus). Redstripe stomachs came from 

Shaw (1999) as mentioned in Field (2004). Steiner (1979) sampled an unknown number of 

yelloweye rockfish stomachs off the Oregon coast and York (2005) sampled 9 stomachs, also off 

the Oregon coast. Steiner also surveyed 51 blue rockfish off the Oregon coast. Juvenile large 

shallow rockfish diets consisted of copper (S. caurinus) and blue rockfish data. Singer (1982) 

analyzed 38 juvenile copper rockfish stomachs and 23 juvenile blue rockfish stomachs, all from 

central California. 

English Sole (FDP) 

Wakefield (1984) collected 49 English sole (Parophrys vetulus) stomachs off Newport, 

Oregon. There was no distinction between juvenile and adult diets in this study; therefore, adult 

diets were used for juvenile diets as well. 

Deep Small Rockfish (FDC) 

Longspine thornyhead (Sebastolobus altivelis), sharpchin rockfish (Sebastes zacentrus), 

and splitnose rockfish (S. diploproa) comprise this group. York (2005) collected 36 sharpchin 

stomachs from Oregon and Shaw (1999) collected 8 stomachs from this species. Brodeur and 

Pearcy (1984) analyzed 62 splitnose stomachs, and longspine thornyhead data were taken from 

Laidig (unpublished data) as described in the Field (2004) and Buckley et al. (1999) samples of 

281 longspine thornyhead stomachs. No juvenile data were available for this group. Juvenile 

diet data were adapted from adult data by reducing fish prey items to juveniles of the associated 

species. Small-bodied fish prey such as small planktivores and benthopelagics were left 

unchanged. 
Deep Large Rockfish (FDO) 

Deep large rockfish diets are based on shortspine thornyhead (Sebastolobus alascanus), 

darkblotched (Sebastes crameri), and rougheye rockfish (S. aleutianus). Buckley (1999) 

collected 473 shortspine thornyhead stomachs and Brodeur and Pearcy (1984) collected 30 

darkblotched stomachs. Yang and Nelson (2000) analyzed 238 rougheye stomach samples from 

Alaska sampled in 1991 and 1993. Juvenile data came from 18 darkblotched rockfish diets 

collected by Miller and Brodeur (2007). 

Canary Rockfish (FPO) 

Adult canary rockfish (S. pinniger) diets come from 561 stomach samples. Brodeur and 

Pearcy (1984) collected 368 stomachs from Oregon and Washington, Lee (2002) collected 104 

stomachs off Oregon and Washington, and York (2005) analyzed 29 stomachs from Oregon. An 

additional 60 stomachs were analyzed by the NOAA-AFSC food habits database from the West 

Coast trawl survey. Juvenile data were adapted from Lea et al. (1999), which contained only 

frequency of occurrence data. 

Midwater Rockfish (FDS) 

Adult midwater rockfish diets consist of widow rockfish (S. entomelas), Pacific ocean 

perch (S. alutus), and yellowtail rockfish (S. flavidus). Yellowtail rockfish made up the greatest 

number of stomachs. Pereyra et al. (1969) collected 22 stomachs off Vancouver Island, Brodeur 

and Pearcy (1984) collected 264 off Oregon and Washington, and Lee (2002) collected 167 off 

Oregon. Additional unpublished data (526 stomachs) were summarized by Field (2004). 

Unpublished diet data (186 stomachs) for Pacific ocean perch were also summarized by Field 

(2004). Brodeur and Pearcy (1984) collected 73 stomachs off Washington and Oregon. Widow 

rockfish stomachs were analyzed from Oregon and northern California by Adams (1987) and 

Lee (2002). Ressler et al. (unpublished) analyzed 41 stomachs from Oregon in 2003. Field 

(2004) also summarized an unpublished analysis of 18 widow rockfish stomachs. Studies of 

adult bocaccio rockfish (Sebastes paucispinis) diet were not available, so this species was not 

included in species-level analysis. However, due to the overfished status of this species and its 

conservation importance, we have separated bocaccio from this functional group in ongoing 

work (Horne et al. in prep.). 

Juvenile midwater rockfish diets come from chilipepper rockfish (S. goodei), yellowtail 

rockfish, widow rockfish, and bocaccio. Reilly et al. (1992) analyzed 195 juvenile widow 

stomachs, 97 yellowtail, 145 chilipepper, and 128 bocaccio from central California. Miller and 

Brodeur (2007) examined an additional 26 yellowtail and 41 juvenile widow rockfish. 

Shallow Small Rockfish (FDB) 

Rosethorn (S. helvomaculatus), greenstriped (S. elongatus), and pygmy rockfish (S. 

wilsoni) are the species in this functional group for which diet information is available. 

Shortbelly (S. jordani) and stripetail (S. saxicola) rockfish accounted for 70% of the biomass for 

this group (NMFS trawl survey, Keller et al. 2007); unfortunately, no adult diet information is 

available for either species. York (2005) analyzed stomachs from each species from Oregon, 

46
with 60 rosethorn, 51 greenstriped, and 49 pygmy stomachs sampled. Juvenile diets came from 

1,027 shortbelly rockfish from central California (Chess et al. 1988, Reilly et al. 1992). 

Large Planktivores (FPL) 

Pacific mackerel (Scomber japonicus) and jack mackerel (Trachurus symetricus) are the 

only 2 species to compose this group. Brodeur et al. (1987) sampled 290 Pacific mackerel and 

132 jack mackerel diets from 1982 to 1984. Miller and Brodeur (2007) analyzed an additional 

316 jack mackerel and 24 Pacific mackerel diets. There was no distinction between adult and 

juvenile diets in either of these studies. There exists a large degree of variability in prey items 

between sample years for these 2 species. 

Small Planktivores (FPS) 

Northern anchovy (Engraulis mordax), Pacific sardine (Sardinops sagax), and Pacific 

herring (Clupea pallasii) constitute the three species in this group. Anchovy and herring diets 

were summarized by Brodeur et al. (1987) from samples collected in 1981 to 1984. Northern 

anchovy data from 1981 consisted of 15 nonempty stomachs. Pacific herring diets consisted of 

94 samples collected from 1981 to 1984. Emmett et al. (2005) examined 184 Pacific sardine 

stomachs from 1999 to 2002. Miller and Brodeur (2007) analyzed stomach samples from each 

of the three species off the Oregon coast in 2000 and 2002 (anchovy n = 132, sardine n = 268, 

herring n = 286). No juvenile data exist for these three species. 

Large Flatfish (FVD) 

Arrowtooth flounder (Atheresthes stomias), Pacific halibut (Hippoglossus stenolepis), 

and petrale sole (Eopsetta jordani) make up the large flatfish group. Large piscivorous flatfish 

diets have been well sampled. Arrowtooth flounder diet studies have largely been concentrated 

in the Gulf of Alaska. Buckley (1999) collected 178 adult stomachs, Yang (1994) collected 337, 

Gotshall (1969) collected 253, and Yang and Nelson (2000) analyzed nearly 3,000. Yang and 

others (Yang 1994, Yang and Nelson 2000) also analyzed 1,657 adult Pacific halibut diets from 

the Gulf of Alaska. Petrale sole diet data were less abundant, with Wakefield (1984) being the 

only source of percent by weight data. Juvenile piscivorous flatfish diets rely again on Yang 

(1994), who analyzed diets from 201 juvenile arrowtooth flounder and 91 juvenile Pacific halibut 

from the Gulf of Alaska. 

Chinook Salmon (FVB) 

Chinook salmon (Oncorhynchus tshawytscha) is the sole species of this group. Brodeur 

et al. (1987) collected 86 adult Chinook salmon stomachs off Washington and Oregon from 1979 

to 1984. Other sources of adult Chinook salmon diets included Silliman (1941), who analyzed 

818 stomachs from 1,939 salmon off Washington, and Merkel (1957), who collected 1,004 from 

near San Francisco. For juveniles, Brodeur and Pearcy (1990) collected 795 stomachs off 

Oregon and Washington, Landingham et al. (1998) collected 38 from British Columbia waters, 

and Schabetsberger (2003) collected 249 from the Columbia River plume. 

47
Deep Miscellaneous Fish (FDD) 

Diets for deep demersal fish are based on Pacific grenadiers (Coryphaenoides acrolepis), 

giant grenadiers (Albatrossia pectoralis), and two deepwater miscellaneous fishes (California 

smoothtongue [Bathylagus stilbius] and twoline eelpout [Bothrocara brunneum]). For adult 

diets, Buckley et al. (1999) collected 29 giant grenadier and 33 Pacific grenadier stomachs from 

the 1992 trawl survey, and Pearcy and Ambler (1974) described two additional Pacific grenadier 

stomachs. Deepwater miscellaneous diets came from 385 California smoothtongue off Santa 

Barbara, California (Cailliet and Ebeling 1990), and 228 twoline eelpout stomachs off central 

California (Monterey Bay) and the Columbia River plume (Ferry 1997). Juvenile diet data were 

available for 483 Pacific grenadiers and 304 giant grenadiers from the 1997 NMFS slope survey 

from Pt. Conception to the U.S.-Canadian border (Drazen et al. 2001). 

Pelagic Sharks (SHP) 

Soupfin sharks (Galeorhinus galeus) are the primary members of this functional group 

and diets were available only for adults. Brodeur et al. (1987) collected 12 soupfin shark 

stomachs off Oregon and Washington from 1981 to 1984, Bonham (1949) analyzed 50 off 

Washington, and Ripley (1946) examined 170 off California. 

Skates and Rays (SSK) 

Longnose (Raja rhina), Bering (Bathyraja interrupta), and big skates (R. binoculata) 

represent this group’s diet data; no juvenile data are available. Longnose skate diets were 

available for central California from Robinson et al. (2007), who analyzed 563 stomachs. 

Wakefield (1984) analyzed an additional 4 samples from Newport, Oregon. A single Bering 

skate and 98 big skate stomachs were also available from Wakefield (1984), caught off Newport. 

No juvenile data were available for of this group. 

Large Demersal Sharks (SHD) 

Sleeper sharks (Somniosus pacificus) make up the majority of this group’s diet data, with 

a small contribution from sixgill sharks (Hexanchus griseus). All shark diets were adapted from 

a review of shark diets worldwide by Cortes (1999), although adult and juvenile diets were not 

differentiated. 

Large Demersal Predators (FVS) 

Lingcod (Ophiodon elongatus) is the sole species making up this group. Lingcod diets 

were not widely available through the California Current. Wakefield (1984) collected 4 adult 

stomachs off Newport, Oregon. A larger sample size was available from Beaudreau and 

Essington (in press), who collected 160 adults and 400 juveniles from the San Juan Islands, 

Washington. 

Sablefish (FMN) 

Sablefish (Anoplopoma fimbria) diets have been well examined coast-wide. Buckley et 

al. (1999) reported on diets from 601 adult sablefish, from Washington to Pt. Conception in the 

48
mid-1990s. Laidig and Adams (1997) also reported 1,868 stomachs collected from Oregon to 

central California, and Cailliet et al. (1988) analyzed 249 from central California as well. 

Brodeur et al. (1987) reported on 138 juvenile stomachs from Oregon and Washington and 

Cailliet et al. (1988) examined 65 juveniles from central California. 

Pacific Hake (FMM) 

Pacific hake (Merluccius productus) is the sole species to represent gadids in the 

California Current because they make up the vast majority of gadid biomass (Keller et al. 2007). 

Both adult and juvenile diets were available from multiple studies coast-wide. In Washington 

and Oregon, Brodeur et al. (1987) collected 156 adult stomachs, Livingston and Alton (1982) 

examined 164 adult stomachs, and Livingston (1983) analyzed 1,499 adult stomachs. Gotshall 

(1969) collected 450 stomachs from the California-Oregon border south to Pt. Conception and 

Rexstad and Pikitch (1986) analyzed 347 stomachs from the West Coast. Additionally, 1,201 

stomachs were available from the NMFS trawl survey, with approximately twice as many 

samples north of Cape Blanco than south (Buckley et al. 1999), and 253 samples from more 

recent surveys (Ressler et al. 2007). Diets of 40 juvenile Pacific hake were available from 

Oregon and Washington (Livingston and Alton 1982) and 364 were analyzed from the trawl 

survey coast-wide (Buckley et al. 1999). 

Small Flatfish (FDF) 

Dover sole (Microstomus pacificus), rex sole (Glyptocephalus zachirus), Pacific sanddab 

(Citharichthys sordidus), and deepsea sole (Embassichthys bathybius) make up this group. 

Juvenile data were unavailable for all 4 species. Dover sole diets were available coast-wide; 770 

stomachs were analyzed from the NMFS trawl survey (Buckley et al. 1999). The remainder of 

samples were from Oregon: 326 from Pearcy and Hancock (1978), 265 from Gabriel and Pearcy 

(1981), 243 from Gabriel (1978), and 24 from Wakefield (1984). Pearcy and Hancock (1978) 

analyzed 614 rex sole and 723 Pacific sanddab diets. Eight additional samples off Oregon were 

examined by Wakefield (1984). Deepsea sole stomachs were analyzed by Buckley et al. (1999), 

with 131 samples coast-wide. 

Deep Vertical Migrators (FBP) 

Myctophids (blue lanternfish [Tarletonbeania crenularis] and California headlightfish 

[Diaphus theta]), Pacific viperfish (Chauliodus macouni), and northern lampfish (Stenobrachius 

leucopsarus) compose this group. Tyler (1970) analyzed 326 samples from two species of 

lampfish. Balanov (1994) analyzed 7 adult Pacific viperfish stomachs from the Bering Sea. 

Northern lampfish stomachs were available from central California (n = 494, Cailliet and Ebeling 

1990) and Oregon (n = 440, Tyler 1970). An unknown number of garnet lampfish 

(Stenobrachius nannochir) stomachs were analyzed by Beamish (1999). Juvenile data came 

from 7 Pacific viperfish from Balanov (1994). 

Large Pelagic Predators (FVT) 

Albacore tuna (Thunnus alalunga) is the sole contributor to this group. All available 

albacore diets were from relatively small individuals, which are immature according to published 

literature (90 cm, Collette and Nauen 1983). Despite the lack of large adults, the data were used 

49
for both adults and juveniles. The majority of data were collected from the 1950s and 1960s in 

central and southern California by Iverson (1971, n = 905 collected from 1968 to 1969) and 

McHugh (1952, n = 107). In the early 1980s Bernard et al. (1985) examined 94 stomachs from 

the same region. 

Small Demersal Sharks (SHB) 

This group is composed of spiny dogfish (Squalus acanthias) and spotted ratfish 

(Hydrolagus colliei). This group was dominated by dogfish biomass (Keller et al. 2007), which 

in turn makes up the majority of predators sampled. For adults, 185 dogfish (Bonham 1954) 

from Washington and 28 ratfish from Oregon (Wakefield 1984) made up the diet. Juvenile data 

were only available for dogfish. Brodeur et al. (1987) examined 113 stomachs from Washington 

and Oregon. Since this was the only data source for juveniles from within the California 

Current, we also included 3,396 juvenile stomachs from off Vancouver Island (Tanasichuck et al. 

1991). 

Miscellaneous Nearshore Fish (FDE) 

This group contains croakers (Sciaenidae), wrymouths (Cryptacanthodidae), and sculpins 

(Cottidae). Quantitative studies were lacking for this group and subsequently the group was 

excluded from the analysis as a predator, though it is included as a prey diet item. 

Seabirds 

Migrating Seabirds (FVO) 

The migratory bird group consists primarily of sooty shearwaters (Puffinus griseus), but 

also includes black-footed albatross (Phoebastria nigripes), Laysan albatross (P. immutabilis), 

Northern fulmar (Fulmarus glacialis), and black-legged kittiwakes (Rissa tridactyla). There 

were no data differentiating adult and juvenile diets. Hunt et al. (2000) conducted a review of 

bird and mammal diets in the subarctic North Pacific, and subdivided the study area into regions, 

one of which approximates the area of the California Current. Also, Wiens and Scott (1975) 

estimated energetic fluxes to sooty shearwaters in Oregon. Because neither data source had a 

sample size associated with it, estimates from the two sources were averaged to determine the 

final diet for this group. 

Diving Seabirds (SP) 

Diving seabird diets are largely informed by two studies: a review of bird and mammal 

diets in the subarctic North Pacific by Hunt et al. (2000) and a broad survey of bird diets in 

central California by Sydeman et al. (1997). For cormorants (Phalacrocorax spp.), pigeon 

guillemots (Cepphus columba), Cassin’s auklets (Ptychoramphus aleuticus), and rhinoceros 

auklets (Cerorhinca monocerata), the review and the empirical study were given equal weights. 

Ancient murrelet (Synthliboramphus antiquus), marbled murrelet (Brachyramphus marmoratus), 

and tufted puffin (Fratercula cirrhata) diets were only available from Hunt et al. (2000). 

Common murres (Uria aalge) make up the largest proportion of biomass for this group, with 

multiple empirical diet studies existing. Sydeman et al. (1997) described 1,985 chick-feeding 

50
events and Ainley et al. (1996) observed 554 feeding bouts, both in central California. Because 

these two empirical studies existed and had such large sample sizes, we did not include the Hunt 

et al. (2000) review data for common murre. 

Surface Seabirds (SB) 

This seabird group is dominated by gulls and empirical diet data were collected from 

chick feeding at western gull (Larus occidentalis) colonies in California (n = 449, Hunt and 

Butler 1980). Storm petrels (Hydrobatidae) play a relatively small role in this group, but some 

diet data were available for them from a review (Hunt et al. 2000). 

Marine Mammals 

Baleen Whales (WHB) 

Gray (Eschrichtius robustus), blue (Balaenoptera musculus), fin (B. physalus), and 

humpback (Megaptera novaeangliae) whales make up the baleen whale group. Baleen whale 

diets were adapted from a marine mammal diet review by Pauly et al. (1998), who provided diet 

data for all four species. Clapham et al. (1997) analyzed stomach contents from fin (n = 1,355) 

and humpback whales (n = 141) caught from 1919 to 1926. Croll et al. (1998) also analyzed an 

unknown number of blue whale fecal samples. Individual species biomass estimates were 

calculated from California Current abundance estimates from Barlow and Fourney (2007). Gray 

whale biomass estimates were obtained from Angliss and Outlaw (2008). 

Toothed Whales (WHT) 

Large toothed whale diets consist of contributions from sperm whales (Physeter 

macrocephalus), pilot whales (Globicephala macrorhynchus), Baird’s beaked whales (Berardius 

bairdii), Cuvier’s beaked whales (Ziphius cavirostris), mesoplodon beaked whales (Mesoplodon 

spp.), and resident killer whales (Orcinus orca). Data for resident killer whales came from Ford 

and Ellis (2006), who observed 529 feeding events from 1974 to 2005 along the coast of British 

Columbia, and Ford et al. (1996), who recorded 135 confirmed fish kills. All remaining species 

data came from a review of marine mammal diets (Pauly et al. 1998). Species biomass estimates 

were adapted from California Current abundance estimates from Barlow and Fourney (2007). 

Transient Orcas (REP) 

Transient killer whale data came from three sources. The majority of data for this group 

contained only predation observation events. From these predation events, we derived a diet 

proportion by accounting for killer whale feeding behavior and biomass of prey items. Jefferson 

et al. (1991) reviewed historic literature predation events on marine mammals, amounting to 764 

different predation observations. Ford et al. (1998) observed 130 predation events on marine 

mammals and seabirds. Pauly et al. (1998) also reviewed literature to derive a proportion diet 

estimate. 

51
Small Cetaceans (WHS) 

Small cetaceans include eight species: short-beaked common dolphin (Delphinus 

delphis), Dall’s porpoise (Phocoenoides dalli), Pacific white-sided dolphin (Lagenorhynchus 

obliquidens), Risso’s dolphin (Grampus griseus), harbor porpoise (Phocoena phocoena), 

northern right whale dolphin (Lissodelphis borealis), striped dolphin (Stenella coeruleoalba), 

and bottlenose dolphin (Tursiops truncatus). All diet data were obtained from the 1998 review 

by Pauly et al. 

Sea Otters (WDG) 

Sea otter (Enhydra lutris) diets come from the southern regions of the California Current. 

The method of data collection for sea otter diets is visual identification of prey items that animals 

retrieve on each dive. As such, sample size is the number of successful dives observed and diet 

is represented by percent frequency of prey types. Van Blaricom et al. (1988) observed 1,025 

successful dives from central California and the Channel Islands. Twenty years prior, Hall and 

Schaller observed 455 dives (1964), McLean (1962) observed 5,882 dives, and Ebert (1968) 

observed 243 dives in central California. Adults and juveniles diets were not differentiated in 

any of the studies; however, since juveniles are thought to learn feeding preferences directly 

from their mothers (Estes et al. 2003), it can be reasonably assumed that adults and juveniles 

have similar diets. 

Pinnipeds (PIN) 

California sea lion (Zalophus californianus), Steller sea lion (Eumetopias jubatus), 

northern fur seal (Callorhinus ursinus), harbor seal (Phoca vitulina), and northern elephant seal 

(Mirounga angustirostris) comprise this group. Adult California sea lion diets were sampled 

from 3 beached individuals in California (Fiscus and Baines 1966). Adult northern fur seals 

were sampled from the California coast from 1958 to 1966 (n = 2,566, Antonelis and Fiscus 

1980). Perez and Biggs (1986) also described the diets of 3,798 individuals from Washington to 

California. Fiscus and Baines (1966) examined 6 northern fur seals from California and 3 Stellar 

sea lions, 2 from California and 1 from Oregon. Clemens and Wilby (1933) sampled 25 juvenile 

fur seals off Vancouver Island, Sinclair (1994) looked at 20 juvenile elephant seals from the 

Channel Islands, and Fiscus and Baines (1966) examined 1 juvenile Steller and 3 juvenile 

California sea lions from California. 

Invertebrates 

No empirical diet data are available for most invertebrate groups. Most invertebrate diets 

came from Field (2004), adapted to differences in functional group members, where necessary. 

A list of invertebrate groups and their contributing species is in Table 2. 

Benthic Carnivores (BC) 

This group is composed of polychaetes, burrowing crustacea, peanut worms, and 

flatworms. Diets were adapted from Field (2004). 

52
Deposit Feeders (BD) 

Benthic detritivores consist of primarily of small crustacea such as amphipods and 

isopods. Diets came from Field (2004). 

Deep Benthic Filter Feeders (BFD) 

This group spans a broad taxonomic range but consisted primarily of anemones, deep sea 

corals, and sponges. Diet data for anemones came from Kruger and Griffiths (1998), who 

analyzed the diet of single temperate species for a year. Sponge diets came from Ribes et al. 

(1999b). 

Other Benthic Filter Feeders (BFF) 

Bivalves and barnacles make up the majority of this group. Field (2004) constituted the 

only source for this group. 

Shallow Benthic Filter Feeders (BFS) 

Soft corals, gorgonians, tunicates, and sea pens are some of the taxa present in this group. 

Diets came from Ribes et al. (1999a) and Field (2004). 

Benthic Herbivorous Grazers (BG) 

The benthic herbivorous grazer group consists of primarily gastropods and urchins, but 

also includes herbivorous decapod shrimps. Data from Field (2004) were used for this group’s 

diets. 

Deep Macrozoobenthos (BMD) 

Sea stars, brittle stars, and carnivorous gastropods comprise this group. Data from Field 

(2004) was adapted for this group’s diet. 

Meiobenthos (BO) 

Flagellates, cilliates, and nematodes make up this group. Data were not available for 

their diet, so it was assumed they eat primarily detritus. 

Megazoobenthos (BML) 

Cancer (genus) and tanner (Chionoecetes bairdi) crabs and lobsters are the primary 

components of this group. Large crab diets are based on Field (2004). We assumed that tanner 

and Dungeness crabs (Cancer magister) contribute the majority of biomass for this group, and 

we weighted Field’s (2004) species diets by their relative biomass to obtain a diet for this 

functional group. 

53
54

Shallow Macrozoobenthos (BMS) 

The only species for which diet data are available is giant octopus (Enteroctopus 

dofleini). Vincent et al. (1998) examined 193 octopus dens in the Gulf of Alaska. 

Cephalopods (CEP) 

Only one source is available to inform squid diets. Karpov and Cailliet (1995) examined 

277 squid stomachs from Monterey Bay. 

Shrimp (PWN) 

Crangon and mysid shrimp comprise this group. Diets were derived from Field (2004). 

Gelatinous Zooplankton (ZG) 

Salps, jellyfish, ctenophores, and comb jellies all contribute to this group. Diets were 

adapted from Field (2004). 

Microzooplankton (ZS) 

Ciliates, dinoflagellates, nanoflagellates, etc., make up this group. Diets were solely 

based on Field (2004). 

Mesozooplankton (ZM) 

Copepods and cladocera comprise this group. Diets were adapted from Field (2004). 

Large Zooplankton (ZL) 

Euphausiids, chaetognaths, pelagic shrimp, pelagic polychaetes, etc., make up this group. 

Diets were adapted from Field (2004) to account for multiple taxa. 
Appendix B: Tables of Functional Group Diets 

Here diet composition is summarized in Tables B-1 through B-10 from the literature 

review by percent weight for members of the 10 feeding guilds in Figure 1. Functional groups 

are from Brand et al. (2007) and the species that comprise them are listed in Table 1 and Table 2. 

Vertebrate predator diets can vary between the juvenile and adult stages. Similarly, vertebrate 

prey may be either juveniles or adults. A Microsoft Excel file of the data is online at http:// 

www.nwfsc.noaa.gov/publications/displayinclude.cfm?incfile=technicalmemorandum2009.inc. 

Table B-1. Diet composition by percent weight for members of feeding guild A in Figure 1. 

Prey Deposit feeders Meiobenthos 

Labile detritus in sediment 0.8182 — 

Large phytoplankton 0.1364 — 

Mesozooplankton 0.0455 — 

Sedimentary detritus — 1.0000 

55
Table B-2. Diet composition by percent weight for members of feeding guild B in Figure 1. 

Deep vertical 

migrators

Large 

planktivores

Pacific 

hake

Shallow la

rockfish

Canary rockfish Cephalopods 

Prey Adult Juv. Adult Juv. Adult Juv. Adult Juv. Adult J

Benthic carnivores — — 0.0077 0.0005 0.0005 — — — — — 0.0

Benthic herb. grazers 0.0285 — 0.0420 — — 0.0031 0.0031 0.0107 — 0.0044 

Cephalopods — — 0.0207 — — 0.0182 0.0182 0.0009 0.0001 0.0003 

Deep misc. fish — — — — — — — 0.0004 — — 

Deep small rockfish — — — — — — — 0.0001 — — 

Deep vertical migrators 0.0199 — 0.0106 0.0106 — — 0.0007 — — Deposit feeders — 0.2640 0.0406 0.0948 0.0948 0.0044 0.0044 0.0020 0.0057 0.0094 0.2

Gelatinous zooplankton 0.0004 — — — — 0.0164 0.0164 — — 0.0006 0.Juv. deep misc. fish — — — — — 0.0167 0.0167 — — — 

Juv. canary rockfish — 0.0069 0.0001 — — — — — — — 

Juv. deep large rockfish — 0.0244 0.0002 — — 0.0027 0.0027 0.0001 — — 

Juv. deep small rockfish — 0.0666 0.0006 — — 0.0030 0.0030 — — — Juv. Pacific hake 0.0010 — — — — 0.0200 0.0200 0.0059 0.0401 — 

Juv. large demersal pred. — — — — — 0.0062 0.0062 — — — 

Juv. large flatfish — — — — — — — 0.0002 — — 

Juv. midwater rockfish — 0.0804 0.0007 — — 0.0030 0.0030 0.0001 — 0.0025 

Juv. misc. nearshore fish — — — — — — — — — 0.0071 

Juv. sh. large rockfish — 0.0122 0.0001 — — 0.0006 0.0006 — — 0.0004 

Juv. sh. small rockfish — 0.0095 0.0001 — — 0.0111 0.0111 — — 0.0003 

Juv. small flatfish — — — — — 0.0070 0.0070 — — 0.0062 

Large phytoplankton — — — — — — — — — — 0.

Large zooplankton 0.9461 0.3120 0.6938 0.6670 0.6670 0.5983 0.5983 0.7827 0.8029 0.9500 

Megazoobenthos 0.0001 — 0.0765 — — 0.0373 0.0373 0.0004 — — 0.

Mesozooplankton — — 0.0612 0.2260 0.2260 0.0789 0.0789 — 0.1419 — 0.2Midwater rockfish — — — — — — — — — 0.0019 

Misc. nearshore fish — — — — — 0.0030 0.0030 0.0003 — — 

Other benthic filter feed. — — — — — — — — — — 0.0

Sh. benthic filter feeders — — — 0.0010 0.0010 — — — — — 

Shallow large rockfish — — — — — — — — — 0.0003 Shallow macrozoobenth. — — — — — — — — 0.0004 — 

Shallow small rockfish — — — — — — 0.0005 — 0.0002 

Shrimp — 0.2240 0.0422 — — 0.1395 0.1395 0.0006 0.0015 — 0.0Small flatfish — — 0.0017 — — — — 0.0015 — — 

Small planktivores 0.0040 — 0.0098 — — 0.0305 0.0305 0.1929 — 0.0164 

56
Table B-3. Diet composition by percent weight for members of feeding guild C in Figure 1. 

Large pelagic 

predators Migrating seabirds Chinook salmon Surface seabir

Prey Adult Juv. Adult Juv. Adult Juv. Adult JuBenthic herbivorous grazers — — — — 0.0003 0.0040 — — Carrion — — — — — — 0.0608 0.06Cephalopods 0.0363 0.0363 0.0720 0.0720 0.0534 0.0142 0.1193 0.11Deep misc. fish — — 0.0227 0.0227 — 0.0045 — — 

Deep small rockfish 0.0078 0.0078 — — — — — — Deep vertical migrators 0.0366 0.0366 0.1293 0.1293 0.0025 0.0030 — — 

Deposit feeders 0.0465 0.0465 — — 0.0002 0.0469 — — 

English sole — — — — — 0.0043 — — 

Gelatinous zooplankton 0.0003 0.0003 — — 0.0002 — 0.0264 0.02

Juv. canary rockfish — — 0.0028 0.0028 — — — — Juv. deep large rockfish 0.0029 0.0029 0.0099 0.0099 0.0214 0.0145 0.0163 0.01

Juv. deep small rockfish — — 0.0271 0.0271 0.0584 0.0397 0.0444 0.04

Juv. Pacific hake — — 0.0813 0.0813 — — 0.0439 0.04

Juv. large flatfish 0.0002 0.0002 — — — 0.0011 — — Juv. midwater rockfish — — 0.0327 0.0327 0.0704 0.0479 0.0536 0.05

Juv. misc. nearshore fish — — — — — — 0.0268 0.02

Juv. shallow large rockfish — — 0.0050 0.0050 0.0107 0.0073 0.0082 0.00

Juv. shallow small rockfish — — 0.0039 0.0039 0.0083 0.0091 0.0063 0.00Juv. small flatfish 0.0002 0.0002 — — — 0.0118 — — 

Large planktivores 0.0078 0.0078 — — — — — — Large zooplankton 0.0298 0.0298 0.0347 0.0347 0.2603 0.0859 0.0610 0.06

Megazoobenthos 0.0083 0.0083 — — 0.0262 0.0651 — — 

Mesozooplankton — — — — — 0.0039 — — 

Midwater rockfish 0.0094 0.0094 — — — — — — 

Misc. nearshore fish 0.0016 0.0016 — — 0.0002 0.0558 — — Other benthic filter feeders — — — — — — 0.0200 0.02Pacific hake 0.0012 0.0012 — — 0.0020 0.0064 — — 

Shallow benthic filter feeders — — — — — 0.0004 — — 

Shallow macrozoobenthos 0.0014 0.0014 — — 0.0001 — — — 

Shrimp — — — — 0.0001 0.0328 — — Small flatfish — — — — 0.0006 0.0607 — — 

Small planktivores 0.8097 0.8097 0.5786 0.5786 0.4840 0.4773 0.5130 0.51

57
Table B-4. Diet composition by percent weight for members of feeding guild D in Figure 1. 

Prey 

Benthic 

herbivorous 

grazers 

Large 

zooplankton 

Mesozooplankton Other benthic 

filter feeders 

Deposit feeders — 0.0070 — — 

Labile detritus in sediment 0.2000 — — — 

Gelatinous zooplankton — 0.0245 — — 

Labile detritus — — — 0.2500 

Large phytoplankton 0.7000 0.5557 0.4000 0.2500 

Large zooplankton — 0.1400 — — 

Macroalgae 0.1000 — — — 

Mesozooplankton — 0.2011 — — 

Microzooplankton — 0.0717 0.2000 0.2500 

Small phytoplankton — — 0.4000 0.2500 

58
Table B-5. Diet composition by percent weight for members of feeding guild E in Figure 1. 

Baleen whales Benthic English sole 

Prey Adult Juv. carnivores Adult Juv. Megazoobenthos Benthic carnivores — — — 0.1600 0.1600 — Benthic herbivorous grazers — — — 0.0426 0.0426 — Carrion — — — — — 0.0125 

Cephalopods 0.0049 0.0049 — — — 0.0005 

Deep benthic filter feeders — — — — — — Deep macrozoobenthos — — — 0.0169 0.0169 0.1595 Deep vertical migrators 0.0049 0.0049 — — — — 

Deposit feeders 0.5863 0.5863 0.5000 0.7020 0.7020 0.2613 

Labile detritus in sediment — — 0.2000 — — — Gelatinous zooplankton — — — — — — 

Juv. deep large rockfish — — — — — 0.0001 

Juv. deep misc. fish — — — — — 0.0018 

Juv. deep small rockfish — — — — — 0.0002 

Juv. large demersal predators — — — — — 0.0002 

Juv. midwater fish — — — — — — 

59

Juv. midwater rockfish — — — — — 0.0002 

Juv. misc. nearshore fish — — — — — 0.0017 

Juv. sablefish — — — — — 0.0002 

Juv. shallow large rockfish — — — — — — 

Juv. shallow small rockfish — — — — — — 

Juv. small demersal sharks — — — — — 0.0017 

Juv. small flatfish — — — — — 0.0050 

Labile detritus — — — — — 0.0451 

Large zooplankton 0.3539 0.3539 — — — — 

Megazoobenthos — — — 0.0199 0.0199 — 

Meiobenthos — — 0.3000 — — — 

Mesozooplankton — — — 0.0029 0.0029 — Other benthic filter feeders — — — 0.0356 0.0356 0.3991 

Shallow benthic filter feeders — — — — — — 

Shrimp — — — 0.0201 0.0201 0.0502 

Small flatfish — — — — — 0.0105 

Small planktivores 0.0501 0.0501 — — — 0.0502 
60

Table B-5 continued horizontally. Diet composition by percent weight for members of feeding guild E in Figure 1. 

Misc. nearshore 

fish 

Shallow small 

Prey (Column list is repeated rockfish Small flatfish from previous page.) Adult Juv. Adult Juv. Shrimp Adult Juv. Benthic carnivores 0.1000 0.1000 — 0.0027 0.1550 0.1713 0.1713 Benthic herbivorous grazers — — 0.2570 — — 0.0170 0.0170 

Carrion — — — — 0.0050 — — 

Cephalopods — — 0.0042 — — 0.0021 0.0021 

Deep benthic filter feeders — — — — — 0.0011 0.0011 

Deep macrozoobenthos — — — — — 0.2759 0.2759 

Deep vertical migrators — — 0.0816 — — 0.0005 0.0005 

Deposit feeders 0.4000 0.4000 0.3449 0.0179 0.3800 0.3776 0.3776 

Labile detritus in sediment — — — — — — — 

Gelatinous zooplankton — — 0.0074 0.0364 — 0.0006 0.0006 

Juv. deep large rockfish — — 0.0007 — — — — 

Juv. deep misc. fish — — — — — — — 

Juv. deep small rockfish — — 0.0019 — — — — 

Juv. large demersal predators — — — — — — — 

Juv. midwater fish — — — — — — — 

Juv. midwater rockfish — — 0.0023 — — — — 

Juv. misc. nearshore fish — — — — — 0.0002 0.0002 

Juv. sablefish — — — — — — — 

Juv. shallow large rockfish — — 0.0003 — — — — 

Juv. shallow small rockfish — — 0.0003 — — — — 

Juv. small demersal sharks — — — — — — — Juv. small flatfish — — — — 0.0050 0.0004 0.0004 

Labile detritus — — — — 0.3500 — — 

Large zooplankton — — 0.2716 0.5892 — 0.0393 0.0393 

Megazoobenthos 0.2000 0.2000 0.0122 0.0003 — 0.0512 0.0512 

Meiobenthos — — — — — — — 

Mesozooplankton — — 0.0143 0.3535 — 0.0016 0.0016 

Other benthic filter feeders 0.2000 0.2000 — — 0.1000 0.0501 0.0501 

Shallow benthic filter feeders — — — — — 0.0076 0.0076 

Shrimp 0.1000 0.1000 0.0013 — 0.0050 0.0035 0.0035 Small flatfish — — — — — — — 

Small planktivores — — — — — — — 
Table B-6. Diet composition by percent weight for members of feeding guild F in Figure 1. 

Sea otters 

Prey 

Deep 

macrozoobenthos Adult Juv. 

Shallow 

macrozoobenthos 

Benthic herbivorous grazers — 0.2596 0.2596 0.0238 

Deep benthic filter feeders 0.3000 — — — 

Deep macrozoobenthos — 0.0008 0.0008 — 

Deposit feeders — — — 0.1260 

Labile detritus 0.2000 — — — 

Large zooplankton 0.2000 — — — 

Megazoobenthos — 0.1631 0.1631 0.7305 

Other benthic filter feeders 0.3000 0.5760 0.5760 0.1187 

Shallow macrozoobenthos — 0.0005 0.0005 0.0010 

61
Table B-7. Diet composition by percent weight for members of feeding guild G in Figure 1. 

Midwater rockfish 

Small demersal 

sharks 

Prey 

Deep 

benthic 

filter feeders 

Gelatinous 

zooplankton Adult Juv. Adult Juv. 

Benthic bacteria 0.1429 — — — — — 

Benthic carnivores — — 0.0054 — 0.0016 — 

Benthic herbivorous grazers — — 0.0236 — — — 

Cephalopods — — 0.0233 — 0.0435 0.0001 

Deep misc. fish — — — — 0.0024 — 

Deep vertical migrators — — 0.0763 — — — 

Deposit feeders 0.1429 — 0.0505 0.0016 0.0120 — 

Gelatinous zooplankton — 0.0268 0.2433 0.0016 0.0268 0.0027 

Juv. canary rockfish — — — — 0.0005 — 

Juv. deep large rockfish — — 0.0164 — 0.0017 — 

Juv. deep small rockfish — — 0.0080 — 0.0047 — 

Juv. English sole — — — — — 0.0054 

Juv. large flatfish — — — — — 0.0018 

Juv. midwater rockfish — — 0.0502 — 0.0057 — 

Juv. Pacific hake — — 0.0182 — 0.0452 0.2099 

Juv. sablefish — — 0.0012 — — — 

Juv. shallow large rockfish — — 0.0008 — 0.0009 — 

Juv. shallow small rockfish — — 0.0015 — 0.0007 — 

Juv. small flatfish — — 0.0340 — 0.0997 0.0003 

Labile detritus 0.1429 — — — — — 

Large phytoplankton 0.1429 0.1547 — — — — 

Large planktivores — — 0.0117 — — — 

Large zooplankton 0.1429 0.3323 0.3799 0.3855 0.4282 0.5904 

Megazoobenthos — — — 0.0017 0.1199 — 

Mesozooplankton 0.1429 0.1607 — 0.6035 — — 

Microzooplankton 0.1429 0.1708 — — — — 

Misc. nearshore fish — — — — 0.0095 — 

Other benthic filter feeders — — 0.0503 — 

Shallow macrozoobenthos — — 0.0001 — — — 

Shrimp — — — — 0.0258 — 

Small demersal sharks — — — — 0.0964 — 

Small phytoplankton — 0.1547 — — — — 

Small planktivores — — 0.0929 — 0.0245 0.1894 

62
Table B-8. Diet composition by percent weight for members of feeding guild H in Figure 1. 

Deep large rockfish Deep misc. fish Deep small rockfish 

Prey Adult Juv. Adult Juv. Adult Juv. 

Benthic carnivores 0.0021 — 0.0447 0.0315 0.0316 0.0316 

Benthic herbivorous grazers 0.1114 — 0.0088 0.0009 0.0150 0.0150 

Canary rockfish — — — — — — 

Carrion 0.0677 — — 0.0975 0.0336 0.0336 

Cephalopods 0.0058 — — 0.3412 0.0880 0.0880 

Chinook salmon — — — — — — 

Deep benthic filter feeders — — — — — — 

Deep large rockfish — — — — 0.0114 — 

Deep macrozoobenthos 0.0001 — 0.0031 0.0053 0.0259 0.0259 

Deep misc. fish 0.0735 — 0.1310 0.0173 0.0141 — 

Deep small rockfish — — — — 0.0118 — 

Deep vertical migrators 0.0137 — 0.0870 0.0773 0.1251 0.1251 

Deposit feeders 0.0919 0.1798 0.2007 0.1847 0.3041 0.3041 

Gelatinous zooplankton — 0.2871 0.0048 0.0004 0.0025 0.0025 

Juv. canary rockfish — — — — — — 

Juv. deep large rockfish 0.0309 — — — — 0.0114 

Juv. deep misc. fish — — — — — 0.0141 

Juv. deep small rockfish 0.0771 — — — — 0.0118 

Juv. large flatfish 0.0020 — — — — — 

Juv. midwater rockfish 0.0405 — — — — 0.0008 

Juv. Pacific hake 0.0773 — — 0.0657 0.0043 0.0043 

Juv. sablefish — — — — — — 

Juv. shallow large rockfish — — — — — — 

Juv. shallow small rockfish 0.0048 — — — — 0.0001 

Juv. small demersal sharks — — — — — — 

Juv. small flatfish 0.0033 — — — — — 

Large demersal predators — — — — — — 

Large demersal sharks — — — — — — 

Large flatfish — — — — — — 

Large pelagic predators — — — — — — 

Large planktivores — — — — — — 

Large zooplankton 0.0867 0.1780 0.1112 0.0457 0.1030 0.1030 

Macroalgae — — — — — — 

Megazoobenthos 0.2830 — 0.0121 0.0371 0.1243 0.1243 

Meiobenthos — — 0.1863 0.0002 — — 

Mesozooplankton 0.0077 0.1083 0.0167 0.0139 0.0045 0.0045 

Midwater fish — — — — — — 

Midwater rockfish — — — — 0.0008 — 

Migrating seabirds — — — — — — 

Misc. nearshore fish — — — — — — 

Other benthic filter feeders — — — 0.0014 — — 

Pacific hake — — — — — — 

Pelagic sharks — — — — — — 

Sablefish — — — — — — 

Shallow benthic filter feeders 0.0006 — 0.0226 — 0.0079 0.0079 

Shallow large rockfish — — — — — — 

Shallow macrozoobenthos 0.0006 — 0.0003 0.0005 — — 

Shallow small rockfish — — — — 0.0001 — 

Shrimp 0.0164 0.2467 0.1707 0.0794 0.0050 0.0050 

Skates and rays — — — — — — 

Small demersal sharks — — — — — — 

Small flatfish — — — — — — 

Small planktivores 0.0029 — — — 0.0870 0.0870 

63
Table B-8 continued horizontally. Diet composition by percent weight for members of feeding guild H 

in Figure 1. 

Diving seabirds Large flatfish 

Large demersal 

Prey (Column list is repeated predators 

from previous page.) Adult Juv. Adult Juv. Adult Juv. 

Benthic carnivores — — 0.0026 — — — 

Benthic herbivorous grazers — — 0.0635 — 0.0326 0.0571 

Canary rockfish — — — — — — 

Carrion — — 0.0075 — — — 

Cephalopods 0.1016 0.1016 0.0119 0.0063 0.0195 0.0058 

Chinook salmon 0.0091 0.0091 0.0033 0.0022 0.0492 — 

Deep benthic filter feeders — — 0.0003 — — — 

Deep large rockfish — — 0.0008 — — — 

Deep macrozoobenthos — — — 0.0347 — — 

Deep misc. fish 0.0084 0.0084 0.0140 0.0090 — 0.0012 

Deep small rockfish — — 0.0022 — — — 

Deep vertical migrators 0.0755 0.0755 0.0057 0.0270 0.0011 0.0062 

Deposit feeders — — 0.0370 0.1277 0.0022 0.0169 

Gelatinous zooplankton — — — — — — 

Juv. canary rockfish 0.0095 0.0095 — — 0.0042 0.0080 

Juv. deep large rockfish — — — — 0.0148 0.0283 

Juv. deep misc. fish — — — — — — 

Juv. deep small rockfish — — — — 0.0404 0.0773 

Juv. large flatfish — — — — — — 

Juv. midwater rockfish 0.1117 0.1117 — — 0.0487 0.0934 

Juv. Pacific hake — — — — — — 

Juv. sablefish — — — — — — 

Juv. shallow large rockfish 0.0170 0.0170 — — 0.0074 0.0142 

Juv. shallow small rockfish 0.0173 0.0173 — — 0.0058 0.0110 

Juv. small demersal sharks — — — — 0.1118 — 

Juv. small flatfish — — — — — — 

Large demersal predators — — — — — — 

Large demersal sharks — — — — — — 

Large flatfish — — 0.0175 — — — 

Large pelagic predators — — — — — — 

Large planktivores — — 0.0045 — — — 

Large zooplankton 0.0823 0.0823 0.0984 0.0956 0.0076 0.0022 

Macroalgae — — — — — — 

Megazoobenthos — — 0.0267 — — — 

Meiobenthos — — — — — — 

Mesozooplankton — — — — — — 

Midwater fish — — — — — — 

Midwater rockfish — — 0.0027 — — — 

Migrating seabirds — — — — — — 

Misc. nearshore fish 0.0910 0.0910 0.0347 0.0259 0.2024 0.2135 

Other benthic filter feeders — — — — — — 

Pacific hake 0.0395 0.0395 0.3752 0.0612 0.0861 0.0612 

Pelagic sharks — — — — — — 

Sablefish — — 0.0003 — — — 

Shallow benthic filter feeders — — 0.0005 — — — 

Shallow large rockfish — — — — — — 

Shallow macrozoobenthos — — 0.0015 — 0.0217 0.0174 

Shallow small rockfish 0.0466 0.0466 — — 0.2067 0.0773 

Shrimp 0.0019 0.0019 0.0489 — — — 

Skates and rays — — 0.0005 — — — 

Small demersal sharks — — — — — — 

Small flatfish 0.0337 0.0337 0.1240 0.0203 0.0763 0.0130 

Small planktivores 0.3549 0.3549 0.1158 0.5901 0.0615 0.2960 

64
65

Table B-8 continued horizontally. Diet composition by percent weight for members of feeding guild H 

in Figure 1. 

Prey (Column list is repeated Pelagic sharks Sablefish Skates and rays 

from previous page.) Adult Juv. Adult Juv. Adult Juv. 

Benthic carnivores — — 0.0032 — — — 

Benthic herbivorous grazers — — 0.0077 0.0325 0.0112 0.0112 

Canary rockfish 0.0027 0.0027 — — — — 

Carrion — — 0.0602 — — — 

Cephalopods 0.0545 0.0545 0.0894 0.0293 0.0444 0.0444 

Chinook salmon 0.0384 0.0384 0.0016 — — — 

Deep benthic filter feeders — — 0.0006 — — — 

Deep large rockfish 0.0096 0.0096 0.0236 — — — 

Deep macrozoobenthos — — 0.0006 — — — 

Deep misc. fish — — 0.0664 0.0470 0.0704 0.0704 

Deep small rockfish 0.0262 0.0262 0.3350 — — — 

Deep vertical migrators — — 0.0109 — 0.0391 0.0391 

Deposit feeders — — 0.0668 0.1183 0.0639 0.0639 

Gelatinous zooplankton 0.0003 0.0003 0.0080 0.1308 — — 

Juv. canary rockfish — — — — 0.0035 0.0035 

Juv. deep large rockfish — — — 0.0051 0.0048 0.0048 

Juv. deep misc. fish — — — — — — 

Juv. deep small rockfish — — — 0.0140 0.0276 0.0276 

Juv. large flatfish — — 0.0016 — — — 

Juv. midwater rockfish — — — 0.0169 0.0173 0.0173 

Juv. Pacific hake — — — — — — 

Juv. sablefish — — 0.0094 — — — 

Juv. shallow large rockfish — — — — 0.0042 0.0042 

Juv. shallow small rockfish — — — — 0.0034 0.0034 

Juv. small demersal sharks — — — — 0.0009 0.0009 

Juv. small flatfish — — — — — — 

Large demersal predators 0.0322 0.0322 — 0.0093 — — 

Large demersal sharks 0.0089 0.0089 — — — — 

Large flatfish 0.1019 0.1019 — — — — 

Large pelagic predators 0.0089 0.0089 — — — — 

Large planktivores 0.0359 0.0359 — — — — 

Large zooplankton — — 0.0339 0.2531 0.0534 0.0534 

Macroalgae — — 0.0025 — — — 

Megazoobenthos — — 0.0073 0.0473 0.0177 0.0177 

Meiobenthos — — — — — — 

Mesozooplankton — — — 0.0006 — — 

Midwater fish — — — — — — 

Midwater rockfish 0.0317 0.0317 0.0086 — — — 

Migrating seabirds 0.0024 0.0024 — — — — 

Misc. nearshore fish 0.2246 0.2246 0.0008 0.0132 0.0032 0.0032 

Other benthic filter feeders — — 0.0015 0.0001 — — 

Pacific hake 0.1156 0.1156 0.1338 — 0.0431 0.0431 

Pelagic sharks 0.0088 0.0088 — — — — 

Sablefish 0.0049 0.0049 — — 0.0002 0.0002 

Shallow benthic filter feeders — — 0.0021 — — — 

Shallow large rockfish 0.0048 0.0048 0.0012 — — — 

Shallow macrozoobenthos 0.0043 0.0043 0.0089 0.0254 0.0456 0.0456 

Shallow small rockfish 0.0037 0.0037 0.0186 — 0.0828 0.0828 

Shrimp — — 0.0043 0.0002 0.2956 0.2956 

Skates and rays 0.0121 0.0121 0.0020 — — — 

Small demersal sharks — — 0.0079 — — — 

Small flatfish 0.0120 0.0120 0.0321 0.0027 0.1659 0.1659 

Small planktivores 0.2556 0.2556 0.0495 0.2542 0.0018 0.0018 
66

Table B-9. Diet composition by percent weight for members of feeding guild I. 

Large demersal 

sharks Pinnipeds Small cetaceans Toothed whales 

Prey Adult Juv. Adult Juv. Adult Juv. Adult Juv. 

Cephalopods 0.3945 0.3945 0.4531 0.3719 0.3334 0.3334 0.6740 0.6740 

Chinook salmon 0.1073 0.1073 0.0116 — 0.0710 0.0710 0.0639 0.0639 

Deep large rockfish — — 0.0109 — — — — — 

Deep small rockfish 0.1073 0.1073 0.0384 — — — — — 

Deep vertical migrators — — — — 0.1580 0.1580 0.0724 0.0724 

Deep. misc. fish 0.0037 0.0037 — 0.0616 — — 0.0397 0.0397 

Deposit feeders — — — 0.0214 0.0276 0.0276 0.0316 0.0316 

Gelatinous zooplankton — — — 0.0060 — — — — 

Juv. Chinook salmon — — — 0.0482 — — — — 

Juv. deep large rockfish — — — 0.0012 — — — — 

Juv. deep small rockfish — — — 0.0034 — — — — 

Juv. midwater rockfish — — — 0.0041 — — — — 

Juv. Pacific hake — — 0.1035 0.0428 — — — — 

Juv. sablefish — — — 0.0086 — — — — 

Juv. shallow large rockfish — — — 0.0006 — — — — 

Juv. shallow small rockfish — — — 0.0005 — — — — 

Juv. skates and rays — — 0.0550 0.0199 — — — — 

Juv. small demersal sharks — — 0.0550 0.0311 — — — — 

Juv. small flatfish — — — 0.0212 — — — — 

Large flatfish — — — — — — <0.00005 <0.00005

Large pelagic predators 0.1073 0.1073 — — — — — — 

Large planktivores — — 0.0018 — 0.0847 0.0847 0.0236 0.0236 

Megazoobenthos 0.0271 0.0271 — — 0.0276 0.0276 0.0316 0.0316 

Midwater rockfish — — 0.0358 — — — — — 

Misc. nearshore fish — — — 0.0207 0.0710 0.0710 — — 

Other benthic filter feeders 0.0542 0.0542 — — — — — — 

Pacific hake 0.0037 0.0037 0.0967 — 0.0710 0.0710 0.0397 0.0397 

Pinnipeds 0.1643 0.1643 — — — — — — 

Sablefish — — 0.0046 — — — <0.00005 <0.00005

Shallow large rockfish — — 0.0054 — — — <0.00005 <0.00005

Shallow macrozoobenthos — — — 0.0172 — — — — 

Shallow small rockfish — — 0.0068 — — — — — 

Shrimp 0.0271 0.0271 — — — — — — 

Small demersal sharks 0.0035 0.0035 — — — — — — 

Small planktivores — — 0.1214 0.3196 0.0847 0.0847 0.0236 0.0236 

Table B-10. Diet composition by percent weight for members of feeding guild J in Figure 1. 

Prey Shallow benthic filter feeders Microzooplankton 

Labile detritus 0.4000 0.2500 

Large phytoplankton 0.2000 0.3750 

Mesozooplankton 0.2000 — 

Microzooplankton 0.2000 — 

Small phytoplankton — 0.3750 
Appendix C: Tables of Fish Species Diets 

Here diet composition for fish species is summarized in Tables C-1 through C-52 from 

the literature review by percent weight. Each table lists prey by descending percent. A 

Microsoft Excel file of the data is online at http://www.nwfsc.noaa.gov/publications/ 

displayinclude.cfm?incfile=technicalmemorandum2009.inc. The predator species appear in 

alphabetical order as follows: 

Albacore tuna (Thunnus alalunga) Table C-1 

Arrowtooth flounder (Atheresthes stomias) Table C-2 

Bering skate (Bathyraja interrupta) Table C-3 

Big skate (Raja binoculata) Table C-4 

Black rockfish (Sebastes melanops) Table C-5 

Blue lanternfish (Tarletonbeania crenularis) Table C-6 

Blue rockfish (Sebastes mystinus) Table C-7 

California headlightfish (Diaphus theta) Table C-8 

Canary rockfish (Sebastes pinniger) Table C-9 

Chinook salmon (Oncorhynchus tshawytscha) Table C-10 

Darkblotched rockfish (Sebastes crameri) Table C-11 

Deepsea sole (Embassichthys bathybius) Table C-12 

Dover sole (Microstomus pacificus) Table C-13 

English sole (Parophrys vetulus) Table C-14 

Garnet lampfish (Tactostoma macropus) Table C-15 

Giant grenadier (Albatrossia pectoralis) Table C-16 

Greenstriped rockfish (Sebastes elongatus) Table C-17 

Jack mackerel (Trachurus symetricus) Table C-18 

Lingcod (Ophiodon elongatus) Table C-19 

Longnose skate (Raja rhina) Table C-20 

Longspine thornyhead (Sebastolobus altivelis) Table C-21 

Northern anchovy (Engraulis mordax) Table C-22 

Northern lampfish (Stenobrachius leucopsarus) Table C-23 

Northern smoothtongue (Bathylagus stilbius) Table C-24 

Pacific grenadier (Coryphaenoides acrolepis) Table C-25 

Pacific hake (Merluccius productus) Table C-26 

Pacific halibut (Hippoglossus stenolepis) Table C-27 

Pacific herring (Clupea pallasii) Table C-28 

Pacific mackerel (Scomber japonicus) Table C-29 

Pacific ocean perch (Sebastes alutus) Table C-30 

Pacific sanddab (Citharichthys sordidus) Table C-31 

Pacific sardine (Sardinops sagax) Table C-32 

Pacific viperfish (Chauliodus macouni) Table C-33 

Petrale sole (Eopsetta jordani) Table C-34 

67
68

Pygmy rockfish (Sebastes wilsoni) Table C-35 

Redstripe rockfish (Sebastes proriger) Table C-36 

Rex sole (Glyptocephalus zachirus) Table C-37 

Rosethorn rockfish (Sebastes helvomaculatus) Table C-38 

Rougheye rockfish (Sebastes aleutianus) Table C-39 

Sablefish (Anoplopoma fimbria) Table C-40 

Sharpchin rockfish (Sebastes zacentrus) Table C-41 

Shortspine thornyhead (Sebastolobus alascanus) Table C-42 

Sixgill shark (Hexanchus griseus) Table C-43 

Sleeper shark (Somniosus pacificus) Table C-44 

Soupfin shark (Galeorhinus galeus) Table C-45 

Spiny dogfish (Squalus acanthias) Table C-46 

Splitnose rockfish (Sebastes diploproa) Table C-47 

Spotted ratfish (Hydrolagus colliei) Table C-48 

Twoline eelpout (Bothrocara brunneum) Table C-49 

Widow rockfish (Sebastes entomelas) Table C-50 

Yelloweye rockfish (Sebastes ruberrimus) Table C-51 

Yellowtail rockfish (Sebastes flavidus) Table C-52 

Table C-1. Diet composition by weight for 

albacore tuna, a member of feeding 

guild B in Figure 11. 

Prey Percent

Small planktivores 0.8097

Deposit feeders 0.0465

Deep vertical migrators 0.0366

Cephalopods 0.0363

Large zooplankton 0.0298

Midwater rockfish 0.0094

Megazoobenthos 0.0083

Deep small rockfish 0.0078

Large planktivores 0.0078

Juv. deep large rockfish 0.0029

Miscellaneous nearshore fish 0.0016

Shallow macrozoobenthos 0.0014

Pacific hake 0.0012

Gelatinous zooplankton 0.0003

Juv. large flatfish 0.0002

Juv. small flatfish 0.0002

Table C-2. Diet composition by weight for 

arrowtooth flounder, a member of 

feeding guild H in Figure 11. 

Prey Percent

Pacific hake 0.4556

Small planktivores 0.1588

Large zooplankton 0.1402

Benthic herbivorous grazers 0.0881

Small flatfish 0.0411

Miscellaneous nearshore fish 0.0331

Shrimp 0.0155

Cephalopods 0.0134

Deep miscellaneous fishes 0.0109

Large flatfish 0.0106

Deposit feeders 0.0069

Deep vertical migrators 0.0064

Carrion 0.0050

Megazoobenthos 0.0044

Large planktivores 0.0037

Benthic carnivores 0.0035

Chinook salmon 0.0026

Shallow benthic filter feeders 0.0001

Gelatinous zooplankton <0.00005

Mesozooplankton <0.00005
Table C-3. Diet composition by weight for 

Bering skate, a member of feeding 

guild E in Figure 11. 

Prey Percent

Shrimp 0.6150

Small flatfish 0.3380

Megazoobenthos 0.0470

Table C-5. Diet composition by weight for 

black rockfish, a member of feeding 

guild B in Figure 11. 

Prey Percent

Small planktivores 0.5076

Large zooplankton 0.1577

Juv. megazoobenthos 0.1158

Gelatinous zooplankton 0.0660

Deposit feeders 0.0346

Shrimp 0.0322

Juv. Pacific hake 0.0272

Juv. Chinook salmon 0.0261

Juv. midwater rockfish 0.0129

Small flatfish 0.0114

Juv. small flatfish 0.0042

Juv. shallow large rockfish 0.0020

Juv. shallow small rockfish 0.0015

Cephalopods 0.0010

Benthic herbivorous grazers 0.0003

Table C-7. Diet composition by weight for 

blue rockfish, a member of feeding 

guild B in Figure 11. 

Prey Percent

Gelatinous zooplankton 0.5502

Small planktivores 0.3517

Large zooplankton 0.0586

Deposit feeders 0.0265

Benthic herbivorous grazers 0.0130

Table C-4. Diet composition by weight for big 

skate, a member of feeding guild E in 

Figure 11. 

Prey Percent

Shrimp 0.5879

Megazoobenthos 0.2165

Small flatfish 0.1542

Deep miscellaneous fishes 0.0356

Sablefish 0.0058

Benthic herbivorous grazers <0.00005

Table C-6. Diet composition by weight for 

blue lanternfish, a member of feeding 

guild A in Figure 11. 

Prey Percent

Large zooplankton 0.9467

Deposit feeders 0.0296

Mesozooplankton 0.0237

Table C-8. Diet composition by weight for 

California headlightfish, a member of 

feeding guild A in Figure 11. 

Prey Percent

Large zooplankton 0.6618

Mesozooplankton 0.2206

Deposit feeders 0.1176

69
Table C-9. Diet composition by weight for 

canary rockfish, a member of feeding 

guild A in Figure 11. 

Prey Percent

Large zooplankton 0.9461

Benthic herbivorous grazers 0.0285

Deep vertical migrators 0.0199

Small planktivores 0.0040

Juv. Pacific hake 0.0010

Gelatinous zooplankton 0.0004

Megazoobenthos 0.0001

Table C-11. Diet composition by weight for 

darkblotched rockfish, a member of 

feeding guild A in Figure 11. 

Prey Percent

Large zooplankton 0.7845

Deep vertical migrators 0.1188

Deposit feeders 0.0552

Mesozooplankton 0.0414

Table C-10. Diet composition by weight for 

Chinook salmon, a member of feeding 

guild B in Figure 11. 

Prey Percent

Small planktivores 0.4840

Large zooplankton 0.2603

Juv. midwater rockfish 0.0704

Juv. deep small rockfish 0.0584

Cephalopods 0.0534

Juv. megazoobenthos 0.0262

Juv. deep large rockfish 0.0214

Juv. shallow large rockfish 0.0107

Juv. shallow small rockfish 0.0083

Deep vertical migrators 0.0025

Pacific hake 0.0020

Miscellaneous nearshore fish 0.0008

Small flatfish 0.0006

Benthic herbivorous grazers 0.0003

Deposit feeders 0.0002

Gelatinous zooplankton 0.0002

Shallow macrozoobenthos 0.0001

Shrimp 0.0001

Table C-12. Diet composition by weight for 

deepsea sole, a member of feeding 

guild D in Figure 11. 

Prey Percent

Benthic carnivores 0.5891

Deep macrozoobenthos 0.1790

Deposit feeders 0.1545

Deep benthic filter feeders 0.0343

Benthic herbivorous grazers 0.0229

Shallow benthic filter feeders 0.0131

Shrimp 0.0050

Megazoobenthos 0.0017

Other benthic filter feeders 0.0003

70
Table C-13. Diet composition by weight for 

Dover sole, a member of feeding guild 

D in Figure 11. 

Prey Percent

Benthic carnivores 0.4316

Deep macrozoobenthos 0.3597

Deposit feeders 0.0992

Other benthic filter feeders 0.0635

Benthic herbivorous grazers 0.0216

Shallow benthic filter feeders 0.0096

Megazoobenthos 0.0065

Large zooplankton 0.0040

Cephalopods 0.0027

Deep benthic filter feeders 0.0006

Gelatinous zooplankton 0.0006

Deep vertical migrators 0.0002

Mesozooplankton 0.0001

Macroalgae <0.00005

Microzooplankton <0.00005

Table C-15. Diet composition by weight for 

garnet lampfish, a member of feeding 

guild C in Figure 11. 

Prey Percent

Mesozooplankton 0.7150

Large zooplankton 0.1934

Deposit feeders 0.0415

Shallow benthic filter feeders 0.0334

Benthic carnivores 0.0167

Table C-14. Diet composition by weight for 

English sole, a member of feeding 

guild D in Figure 11. 

Prey Percent

Deposit feeders 0.7020

Benthic carnivores 0.1600

Benthic herbivorous grazers 0.0426

Other benthic filter feeders 0.0356

Shrimp 0.0201

Megazoobenthos 0.0199

Deep macrozoobenthos 0.0169

Mesozooplankton 0.0029

Table C-16. Diet composition by weight for 

giant grenadier, a member of feeding 

guild E in Figure 11. 

Prey Percent

Shrimp 0.3704

Deep miscellaneous fishes 0.2499

Large zooplankton 0.1523

Deposit feeders 0.1299

Cephalopods 0.0743

Benthic herbivorous grazers 0.0198

Deep macrozoobenthos 0.0032

Shallow macrozoobenthos 0.0003

71
Table C-17. Diet composition by weight for 

greenstriped rockfish, a member of 

feeding guild A in Figure 11. 

Prey Percent

Large zooplankton 0.7220

Deep vertical migrators 0.1349

Deposit feeders 0.0826

Benthic herbivorous grazers 0.0272

Cephalopods 0.0141

Megazoobenthos 0.0075

Mesozooplankton 0.0062

Shrimp 0.0056

Table C-19. Diet composition by weight for 

lingcod, a member of feeding guild H 

in Figure 11. 

Prey Percent

Shallow small rockfish 0.2067

Miscellaneous nearshore fish 0.2024

Juv. small demersal sharks 0.1118

Pacific hake 0.0861

Small flatfish 0.0763

Small planktivores 0.0615

Chinook salmon 0.0492

Juv. midwater rockfish 0.0487

Juv. deep small rockfish 0.0404

Benthic herbivorous grazers 0.0326

Shallow macrozoobenthos 0.0217

Cephalopods 0.0195

Juv. deep large rockfish 0.0148

Large zooplankton 0.0076

Juv. shallow large rockfish 0.0074

Juv. shallow small rockfish 0.0058

Juv. canary rockfish 0.0042

Deposit feeders 0.0022

Deep vertical migrators 0.0011

Table C-18. Diet composition by weight for 

jack mackerel, a member of feeding 

guild A in Figure 11. 

Prey Percent

Large zooplankton 0.5674

Shrimp 0.2996

Small planktivores 0.0668

Juv. small flatfish 0.0130

Miscellaneous nearshore fish 0.0066

Benthic herbivorous grazers 0.0061

Juv. Pacific hake 0.0058

Juv. deep miscellaneous fish 0.0057

Juv. megazoobenthos 0.0055

Juv. midwater rockfish 0.0052

Juv. deep small rockfish 0.0051

Juv. deep large rockfish 0.0050

Juv. shallow small rockfish 0.0049

Deposit feeders 0.0016

Cephalopods 0.0010

Juv. shallow large rockfish 0.0003

Mesozooplankton 0.0003

72
Table C-20. Diet composition by weight for 

longnose skate, a member of feeding 

guild E in Figure 11. 

Prey Percent

Shrimp 0.2126

Small flatfish 0.1293

Shallow small rockfish 0.1044

Deep miscellaneous fishes 0.0870

Deposit feeders 0.0803

Large zooplankton 0.0673

Shallow macrozoobenthos 0.0575

Cephalopods 0.0559

Pacific hake 0.0543

Deep vertical migrators 0.0493

Juv. deep small rockfish 0.0348

Juv. midwater rockfish 0.0218

Benthic herbivorous grazers 0.0141

Juv. deep large rockfish 0.0060

Juv. shallow large rockfish 0.0053

Juv. canary rockfish 0.0044

Juv. shallow small rockfish 0.0042

Miscellaneous nearshore fish 0.0040

Surfperch 0.0023

Small planktivores 0.0023

Megazoobenthos 0.0017

Small demersal sharks 0.0011

Table C-22. Diet composition by weight for 

northern anchovy, a member of 

feeding guild A in Figure 11. 

Prey Percent

Large zooplankton 0.6515

Large phytoplankton 0.2855

Shrimp 0.0277

Benthic herbivorous grazers 0.0241

Mesozooplankton 0.0070

Juv. megazoobenthos 0.0035

Deposit feeders 0.0004

Cephalopods 0.0003

Table C-21. Diet composition by weight for 

longspine thornyhead, a member of 

feeding guild H in Figure 11. 

Prey Percent

Deposit feeders 0.2362

Megazoobenthos 0.1966

Small planktivores 0.1375

Cephalopods 0.0869

Deep vertical migrators 0.0812

Carrion 0.0531

Benthic carnivores 0.0499

Deep macrozoobenthos 0.0410

Deep miscellaneous fishes 0.0223

Deep small rockfish 0.0187

Deep large rockfish 0.0180

Large zooplankton 0.0167

Shallow benthic filter feeders 0.0124

Benthic herbivorous grazers 0.0114

Shrimp 0.0080

Pacific hake 0.0068

Gelatinous zooplankton 0.0015

Midwater rockfish 0.0012

Mesozooplankton 0.0002

Shallow small rockfish 0.0001

Table C-23. Diet composition by weight for 

northern lampfish, a member of 

feeding guild C in Figure 11. 

Prey Percent

Large zooplankton 0.6401

Mesozooplankton 0.2509

Deposit feeders 0.1090

73
Table C-24. Diet composition by weight for 

northern smoothtongue, a member of 

feeding guild G in Figure 11. 

Prey Percent

Shallow benthic filter feeders 0.2779

Deposit feeders 0.2323

Large zooplankton 0.2073

Mesozooplankton 0.1788

Gelatinous zooplankton 0.0592

Benthic carnivores 0.0399

Benthic herbivorous grazers 0.0034

Cephalopods 0.0011

Table C-26. Diet composition by weight for 

Pacific hake, a member of feeding 

guild A in Figure 11. 

Prey Percent

Large zooplankton 0.7827

Small planktivores 0.1929

Benthic herbivorous grazers 0.0107

Juv. Pacific hake 0.0059

Deposit feeders 0.0020

Small flatfish 0.0015

Cephalopods 0.0009

Deep vertical migrators 0.0007

Shrimp 0.0006

Shallow small rockfish 0.0005

Deep miscellaneous fishes 0.0004

Megazoobenthos 0.0004

Miscellaneous nearshore fish 0.0003

Juv. large flatfish 0.0002

Deep small rockfish 0.0001

Juv. deep large rockfish 0.0001

Juv. midwater rockfish 0.0001

Table C-25. Diet composition by weight for 

Pacific grenadier, a member of feeding 

guild F in Figure 11. 

Prey Percent

Cephalopods 0.3490

Deposit feeders 0.2426

Deep miscellaneous fishes 0.2283

Benthic carnivores 0.0980

Megazoobenthos 0.0278

Shrimp 0.0267

Large zooplankton 0.0180

Mesozooplankton 0.0050

Deep macrozoobenthos 0.0040

Shallow macrozoobenthos 0.0005

Table C-27. Diet composition by weight for 

Pacific halibut, a member of feeding 

guild H in Figure 11. 

Prey Percent

Pacific hake 0.3763

Deposit feeders 0.2003

Megazoobenthos 0.1551

Deep miscellaneous fishes 0.0366

Small flatfish 0.0364

Small planktivores 0.0333

Large flatfish 0.0305

Carrion 0.0260

Miscellaneous nearshore fish 0.0208

Cephalopods 0.0128

Large planktivores 0.0125

Shallow macrozoobenthos 0.0098

Benthic herbivorous grazers 0.0096

Chinook salmon 0.0096

Shrimp 0.0085

Deep vertical migrators 0.0079

Large zooplankton 0.0039

Skates and rays 0.0035

Shallow benthic filter feeders 0.0031

Sablefish 0.0021

Benthic carnivores 0.0011

Deep macrozoobenthos 0.0002

Deep benthic filter feeders 0.0001

74
Table C-28. Diet composition by weight for 

Pacific herring, a member of feeding 

guild A in Figure 11. 

Prey Percent 

Large zooplankton 0.8010

Shrimp 0.0833

Deposit feeders 0.0610

Mesozooplankton 0.0325

Juv. megazoobenthos 0.0130

Small planktivores 0.0089

Benthic herbivorous grazers 0.0003

Table C-30. Diet composition by weight for 

Pacific ocean perch, a member of 

feeding guild A in Figure 11. 

Prey Percent

Large zooplankton 0.6452

Deep vertical migrators 0.1605

Deposit feeders 0.0822

Benthic herbivorous grazers 0.0549

Large planktivores 0.0324

Cephalopods 0.0248

Table C-29. Diet composition by weight for 

Pacific mackerel, a member of feeding 

guild A in Figure 11. 

Prey Percent 

Large zooplankton 0.6242

Mesozooplankton 0.1448

Juv. megazoobenthos 0.0640

Cephalopods 0.0326

Juv. Pacific hake 0.0318

Gelatinous zooplankton 0.0301

Juv. deep miscellaneous fish 0.0258

Juv. shallow small rockfish 0.0164

Juv. large demersal predators 0.0115

Deposit feeders 0.0067

Shrimp 0.0055

Juv. small flatfish 0.0019

Juv. deep small rockfish 0.0012

Juv. midwater rockfish 0.0012

Juv. deep large rockfish 0.0009

Juv. shallow large rockfish 0.0008

Benthic herbivorous grazers 0.0006

Table C-31. Diet composition by weight for 

Pacific sanddab, a member of feeding 

guild E in Figure 11. 

Prey Percent

Shrimp 0.4166

Benthic herbivorous grazers 0.2514

Deposit feeders 0.2374

Benthic carnivores 0.0866

Large zooplankton 0.0028

Small flatfish 0.0018

Gelatinous zooplankton 0.0012

Mesozooplankton 0.0010

Miscellaneous nearshore fish 0.0006

Cephalopods 0.0004

Pacific hake 0.0002

75
Table C-32. Diet composition by weight for 

Pacific sardine, a member of feeding 

guild A in Figure 11. 

Prey Percent

Large zooplankton 0.5429

Large phytoplankton 0.2279

Mesozooplankton 0.2157

Shrimp 0.0131

Deposit feeders 0.0005

Table C-34. Diet composition by weight for 

petrale sole, a member of feeding guild 

E in Figure 11. 

Prey Percent

Small flatfish 0.6212

Shrimp 0.2546

Miscellaneous nearshore fish 0.0585

Large flatfish 0.0378

Deposit feeders 0.0122

Deep miscellaneous fishes 0.0056

Benthic herbivorous grazers 0.0041

Cephalopods 0.0041

Deep benthic filter feeders 0.0020

Table C-36. Diet composition by weight for 

redstripe rockfish, a member of 

feeding guild A in Figure 11. 

Prey Percent

Large zooplankton 1.0000

Table C-33. Diet composition by weight for 

Pacific viperfish, not a member of a 

feeding guild. 

Prey Percent

Deep vertical migrators 0.9989

Mesozooplankton 0.0011

Table C-35. Diet composition by weight for 

pygmy rockfish, a member of feeding 

guild A in Figure 11. 

Prey Percent

Large zooplankton 0.9193

Mesozooplankton 0.0568

Deposit feeders 0.0226

Cephalopods 0.0009

Benthic herbivorous grazers 0.0004

Table C-37. Diet composition by weight for 

rex sole, a member of feeding guild D 

in Figure 11. 

Prey Percent 

Benthic carnivores 0.6667

Deposit feeders 0.3189

Other benthic filter feeders 0.0144

76
Table C-38. Diet composition by weight for 

rosethorn rockfish, a member of 

feeding guild G in Figure 11. 

Prey Percent

Deposit feeders 0.4592

Benthic herbivorous grazers 0.3549

Deep vertical migrators 0.0706

Large zooplankton 0.0675

Megazoobenthos 0.0149

Mesozooplankton 0.0135

Gelatinous zooplankton 0.0105

Juv. midwater rockfish 0.0032

Juv. deep small rockfish 0.0027

Cephalopods 0.0011

Juv. deep large rockfish 0.0010

Juv. shallow large rockfish 0.0005

Juv. shallow small rockfish 0.0004

Table C-39. Diet composition by weight for 

rougheye rockfish, a member of 

feeding guild G in Figure 11. 

Prey Percent

Benthic herbivorous grazers 0.4875

Shrimp 0.1129

Large zooplankton 0.0875

Small planktivores 0.0869

Deposit feeders 0.0810

Cephalopods 0.0494

Deep vertical migrators 0.0340

Megazoobenthos 0.0262

Miscellaneous nearshore fish 0.0261

Pacific hake 0.0036

Benthic carnivores 0.0032

Other benthic filter feeders 0.0012

Small flatfish 0.0004

77
Table C-40. Diet composition by weight for 

sablefish, a member of feeding guild H 

in Figure 11. 

Prey Percent

Deep small rockfish 0.3350

Pacific hake 0.1338

Cephalopods 0.0894

Deposit feeders 0.0668

Deep miscellaneous fishes 0.0664

Carrion 0.0602

Small planktivores 0.0495

Large zooplankton 0.0339

Small flatfish 0.0321

Deep large rockfish 0.0236

Shallow small rockfish 0.0186

Deep vertical migrators 0.0109

Juv. sablefish 0.0094

Shallow macrozoobenthos 0.0089

Midwater rockfish 0.0086

Gelatinous zooplankton 0.0080

Small demersal sharks 0.0079

Benthic herbivorous grazers 0.0077

Megazoobenthos 0.0073

Shrimp 0.0043

Benthic carnivores 0.0032

Macroalgae 0.0025

Shallow benthic filter feeders 0.0021

Skates and rays 0.0020

Chinook salmon 0.0016

Juv. large flatfish 0.0016

Other benthic filter feeders 0.0015

Shallow large rockfish 0.0012

Miscellaneous nearshore fish 0.0008

Deep benthic filter feeders 0.0006

Deep macrozoobenthos 0.0006

Table C-41. Diet composition by weight for 

sharpchin rockfish, a member of 

feeding guild A in Figure 11. 

Prey Percent

Large zooplankton 0.4462

Deep vertical migrators 0.3571

Deposit feeders 0.1164

Benthic herbivorous grazers 0.0399

Mesozooplankton 0.0221

Cephalopods 0.0103

Gelatinous zooplankton 0.0080

78
Table C-42. Diet composition by weight for 

shortspine thornyhead, a member of 

feeding guild A in Figure 11. 

Prey Percent

Megazoobenthos 0.3196

Benthic herbivorous grazers 0.1206

Deposit feeders 0.0955

Juv. Pacific hake 0.0872

Deep small rockfish 0.0871

Deep miscellaneous fishes 0.0830

Carrion 0.0764

Midwater rockfish 0.0457

Deep large rockfish 0.0349

Shrimp 0.0185

Cephalopods 0.0066

Shallow small rockfish 0.0054

Canary rockfish 0.0039

Juv. small flatfish 0.0037

Small planktivores 0.0032

Benthic carnivores 0.0024

Juv. large flatfish 0.0023

Deep vertical migrators 0.0017

Large zooplankton 0.0009

Shallow benthic filter feeders 0.0007

Shallow macrozoobenthos 0.0007

Deep macrozoobenthos 0.0001

Table C-44. Diet composition by weight for 

sleeper shark, a member of feeding 

guild H in Figure 11. 

Prey Percent

Cephalopods 0.3890

Pinnipeds 0.1670

Chinook salmon 0.1110

Deep small rockfish 0.1110

Large pelagic predators 0.1110

Other benthic filter feeders 0.0560

Megazoobenthos 0.0280

Shrimp 0.0280

Table C-43. Diet composition by weight for 

sixgill shark, a member of feeding 

guild F in Figure 11. 

Prey Percent

Cephalopods 0.5689

Deep miscellaneous fishes 0.1143

Pacific hake 0.1143

Small demersal sharks 0.1068

Pinnipeds 0.0888

Other benthic filter feeders 0.0030

79
Table C-45. Diet composition by weight for 

soupfin shark, a member of feeding 

guild H in Figure 11. 

Prey Percent

Small planktivores 0.2556

Miscellaneous nearshore fish 0.2246

Pacific hake 0.1156

Large flatfish 0.1019

Cephalopods 0.0545

Chinook salmon 0.0384

Large planktivores 0.0359

Large demersal predators 0.0322

Midwater rockfish 0.0317

Deep small rockfish 0.0262

Skates and rays 0.0121

Small flatfish 0.0120

Deep large rockfish 0.0096

Large demersal sharks 0.0089

Large pelagic predators 0.0089

Pelagic sharks 0.0088

Sablefish 0.0049

Shallow large rockfish 0.0048

Shallow macrozoobenthos 0.0043

Shallow small rockfish 0.0037

Canary rockfish 0.0027

Migrating seabirds 0.0024

Gelatinous zooplankton 0.0003

Table C-47. Diet composition by weight for 

splitnose rockfish, a member of 

feeding guild A in Figure 11. 

Prey Percent 

Large zooplankton 0.9462

Deep vertical migrators 0.0310

Deposit feeders 0.0207

Cephalopods 0.0021

Table C-46. Diet composition by weight for 

spiny dogfish, a member of feeding 

guild A in Figure 11. 

Prey Percent

Large zooplankton 0.5265

Small demersal sharks 0.1209

Small flatfish 0.0968

Megazoobenthos 0.0569

Cephalopods 0.0535

Pacific hake 0.0465

Gelatinous zooplankton 0.0330

Small planktivores 0.0308

Shrimp 0.0096

Miscellaneous nearshore fish 0.0039

Juv. shallow small rockfish 0.0030

Juv. canary rockfish 0.0030

Juv. deep large rockfish 0.0030

Juv. deep small rockfish 0.0030

Juv. midwater rockfish 0.0030

Juv. shallow large rockfish 0.0030

Table C-48. Diet composition by weight for 

spotted ratfish, a member of feeding 

guild H in Figure 11. 

Prey Percent

Megazoobenthos 0.3945

Other benthic filter feeders 0.2696

Small flatfish 0.1051

Shrimp 0.0965

Deposit feeders 0.0558

Pacific hake 0.0379

Miscellaneous nearshore fish 0.0296

Deep miscellaneous fishes 0.0111

80
81

Table C-49. Diet composition by weight for 

twoline eelpout, a member of feeding 

guild G in Figure 11. 

Prey Percent

Deposit feeders 0.3704

Large zooplankton 0.3704

Deep miscellaneous fishes 0.2111

Cephalopods 0.0482

Table C-51. Diet composition by weight for 

yelloweye rockfish, a member of 

feeding guild H in Figure 11. 

Prey Percent

Small planktivores 0.3273

Deposit feeders 0.1913

Miscellaneous nearshore fish 0.1450

Small flatfish 0.1267

Benthic herbivorous grazers 0.0900

Juv. midwater rockfish 0.0508

Midwater rockfish 0.0382

Juv. shallow large rockfish 0.0077

Cephalopods 0.0066

Juv. shallow small rockfish 0.0060

Shallow large rockfish 0.0058

Shallow small rockfish 0.0045

Large zooplankton 0.0001

Table C-50. Diet composition by weight for 

widow rockfish, a member of feeding 

guild G in Figure 11. 

Prey Percent

Gelatinous zooplankton 0.4829

Large zooplankton 0.3419

Deposit feeders 0.0460

Deep vertical migrators 0.0422

Juv. Pacific hake 0.0422

Benthic carnivores 0.0126

Cephalopods 0.0095

Small planktivores 0.0074

Juv. sablefish 0.0029

Juv. shallow small rockfish 0.0018

Juv. deep large rockfish 0.0018

Juv. deep small rockfish 0.0018

Juv. midwater rockfish 0.0018

Juv. shallow large rockfish 0.0018

Benthic herbivorous grazers 0.0017

Juv. small flatfish 0.0013

Shallow macrozoobenthos 0.0003

Deep miscellaneous fishes <0.00005

Small flatfish <0.00005

Table C-52. Diet composition by weight for 

yellowtail rockfish, a member of 

feeding guild G in Figure 11. 

Prey Percent

Large zooplankton 0.4013

Gelatinous zooplankton 0.2208

Juv. Pacific hake 0.1498

Small planktivores 0.0699

Cephalopods 0.0523

Deep vertical migrators 0.0459

Juv. small flatfish 0.0324

Benthic herbivorous grazers 0.0132

Deposit feeders 0.0046

Juv. midwater rockfish 0.0041

Juv. deep small rockfish 0.0034

Juv. deep large rockfish 0.0012

Juv. shallow large rockfish 0.0006

Juv. shallow small rockfish 0.0005

Most NOAA Technical Memorandums NMFS-NWFSC are available online at the

Northwest Fisheries Science Center web site (http://www.nwfsc.noaa.gov).

NOAA Technical Memorandum NMFS-NWFSC102 Reppond, K.D. 2009. Biochemistry of red king crab (Paralithodes camtschaticus) from different locations in 

Alaskan waters. U.S. Dept. Commer., NOAA Tech. Memo. NMFS-NWFSC-102, 16 p. NTIS number pending.

101 Sands, N.J., K. Rawson, K.P. Currens, W.H. Graeber, M.H. Ruckelshaus, R.R. Fuerstenberg, and J.B. 

Scott. 2009. Determination of independent populations and viability criteria for the Hood Canal summer chum 

salmon evolutionarily significant unit. U.S. Dept. Commer., NOAA Tech. Memo. NMFS-NWFSC-101, 58 p. 

NTIS number pending. 

100 Linbo, T.L. 2009. Zebrafish (Danio rerio) husbandry and colony maintenance at the Northwest Fisheries Science Center. U.S. Dept. Commer., NOAA Tech. Memo. NMFS-NWFSC-100, 62 p. NTIS number PB2009-

113299.

 99 Rawson, K., N.J. Sands, K.P. Currens, W.H. Graeber, M.H. Ruckelshaus, R.R. Fuerstenberg, and J.B. 

Scott. 2009. Viability criteria for the Lake Ozette sockeye salmon evolutionarily significant unit. U.S. Dept. 

Commer., NOAA Tech. Memo. NMFS-NWFSC-99, 38 p. NTIS number PB2009-113298. 

 98 Johnson, L.L., G.M. Ylitalo, M.S. Myers, B.F. Anulacion, J. Buzitis, W.L. Reichert, and T.K. Collier. 

2009. Polycyclic aromatic hydrocarbons and fish health indicators in the marine ecosystem in Kitimat, 

British Columbia. U.S. Dept. Commer., NOAA Tech. Memo. NMFS-NWFSC-98, 123 p. NTIS number 

PB2009-110295. 

 97 Roegner, G.C., H.L. Diefenderfer, A.B. Borde, R.M. Thom, E.M. Dawley, A.H. Whiting, S.A. 

Zimmerman, and G.E. Johnson. 2009. Protocols for monitoring habitat restoration projects in the lower

Columbia River and estuary. U.S. Dept. Commer., NOAA Tech. Memo. NMFS-NWFSC-97, 63 p. NTIS

number PB2009-113671. 

 96 Currens, K.P., R.R. Fuerstenberg, W.H. Graeber, K. Rawson, M.H. Ruckelshaus, N.J. Sands, and J.B. 

Scott. 2009. Identification of an independent population of sockeye salmon in Lake Ozette, Washington. 

U.S. Dept. Commer., NOAA Tech. Memo. NMFS-NWFSC-96, 18 p. NTIS number PB2009-108060. 

 95 Harms, J.H., J.A. Benante, and R.M. Barnhart. 2008. The 2004–2007 hook and line survey of shelf 

rockfish in the Southern California Bight: Estimates of distribution, abundance, and length composition. 

U.S. Dept. Commer., NOAA Tech. Memo. NMFS-NWFSC-95, 110 p. NTIS number PB2009-106740.

Recent NOAA Technical Memorandums

published by the

Northwest Fisheries Science Center