Appendix A 

Living Resources 

August 2012
Appendix A, Yaquina ODMDS Evaluation/EA

Appendix A 

Living Resources 

Table of Contents 

Plankton and Fish Larvae .............................................................................................................. A-2

Zooplankton .............................................................................................................................. A-2

Ichthyoplankton ........................................................................................................................ A-3

Benthic Invertebrates .................................................................................................................... A-4

Benthic Invertebrate Studies by USACE and EPA (1984-2000) .............................................. A-4

Benthic Invertebrate Studies by USACE and EPA (2008) ....................................................... A-7

Fish and Epibenthic Invertebrate Species ................................................................................... A-19

August 2008 EPA Trawl Survey ............................................................................................. A-23

Threatened or Endangered Species ............................................................................................. A-28

Other Wildlife ............................................................................................................................. A-32

Commercial and Recreational Fisheries - Economics................................................................. A-33

Marine Reserves .......................................................................................................................... A-33

References ................................................................................................................................... A-34

LIST OF FIGURES 

Figure A-1. 2008 Sampling Stations at Yaquina ODMDS .......................................................... A-9

Figure A-2. Average Number of Individuals and Species per Grab by Location, June 2008 .... A-10

Figure A-3. Density of Benthic Invertebrates, June 2008 (number per m2

) .............................. A-17

Figure A-4. Density of Benthic Invertebrates, August 2008 (number per m2

) .......................... A-18

Figure A-5. Fishery Resources ................................................................................................... A-20

Figure A-6. Commercial and Recreational Shellfish .................................................................. A-21

Figure A-7. Recreational Dungeness Crab ................................................................................. A-22

Figure A-8. Trawl Locations at Yaquina Ocean Disposal Sites, August 2008 .......................... A-25

Figure A-9. Wildlife Resources ................................................................................................. A-32

LIST OF TABLES 

Table A-1. Disposal Activities at North ODMDS Drop Zone Prior to Sampling ........................ A-9

Table A-2. Number of Benthic Species per Sampling Location, June 2008 .............................. A-11

Table A-3. Number of Benthic Individuals per Sampling Location, June 2008 ........................ A-12

Table A-4. Number of Benthic Species per Sampling Location, August 2008 ......................... A-15

Table A-5. Number of Benthic Individuals per Sampling Location, August 2008 .................... A-16

Table A-6. Summary of Fish Data for Each Trawl Area, August 2008 ..................................... A-26

Table A-7. Dungeness Crab Trawl Data, August 2008.............................................................. A-27

Table A-8. Epibenthic Invertebrate Data, August 2008 ............................................................. A-28

Table A-9. Threatened or Endangered Species that May Occur at North and South ODMDS . A-29

ATTACHMENT 

A. Demersal Fish Data by Location, August 2008 

B. 2011 Yaquina ODMDS Bathymetry 
Appendix A, Yaquina ODMDS Evaluation/EA A-2

Appendix A 

Living Resources 

Information on aquatic resources offshore of Yaquina Bay was obtained from published and 

unpublished reports, peer-reviewed literature, and personal communications. In addition, the U.S. 

Army Corps of Engineers (USACE) and/or U.S. Environmental Protection Agency (EPA) have 

conducted field sampling specifically related to dredge material disposal periodically since 1984 to 

collect information on distribution and abundance of benthic infauna. In 2008, in addition to benthic 

infaunal sampling, EPA conducted benthic trawls to collect presence/absence information on 

epibenthic invertebrates and benthic fish at the Yaquina North and South ocean dredged material 

disposal sites (ODMDS). 

PLANKTON AND FISH LARVAE

Zooplankton 

Published literature within the last decade have examined the zooplankton community dynamics off 

the Oregon coast in relation to the physical oceanographic patterns of the California current and the 

localized nearshore upwelling. Keister and Peterson (2003) provided a discussion of the zooplankton 

community found off the central Oregon coast in the Newport coastal area (along the Newport 

hydrographic line). They indicate that the zooplankton community is influenced strongly by seasonal 

variations in wind and current patterns. During late spring and summer, northwesterly winds set up 

equatorward flow and coastal upwelling. Northwesterly winds dominate from April/May-September; 

periodic relaxations or southwesterly storms rapidly affect the hydrography of nearshore areas, but 

offshore of about 30 kilometers (km), conditions are less variable. Boreal neritic copepods such as 

Pseudocalanus mimus, Calanus marshallae, Centropages abdominalis, Acartia longiremis, and 

Acartia hudsonica dominate the coastal plankton during summer (Peterson and Miller 1977). In early 

fall, winds reverse and upwelling ceases; during autumn and winter, winds are predominantly 

southwesterly, the Davidson current flows poleward and offshore surface waters are transported 

onshore. In winter, the coastal zooplankton is populated by warm-water species such as Mesocalanus 

tenuicornis, Paracalanus parvus, Ctenocalanus vanus, Clausocalanus spp., Acartia tonsa, and 

Corycaeus anglicus (Peterson and Miller 1977). 

Ressler et al. (2005) studied the spatial distribution of euphausiid aggregations in Oregon and northern 

California. Euphausiids, particularly Euphausia pacific and Thysanoessa spinifera, are important prey 

items for juvenile and adult salmonids, spiny dogfish, rockfishes, Pacific hake, seabirds, and marine 

mammals. Seventeen east-west transects were conducted; with the furthest north transect off of 

Newport, Oregon, in water as shallow as 50 meters. Euphausiids were not common in depths 

shallower than 50 meters. The authors found that the distribution of euphausiid patches was not 

uniform or random. They found that euphausiids clustered in two locations, inshore of Heceta Bank 

and off of Cape Blanco. The clusters were found to correlate with near-surface chlorophyll. In 

addition, the interaction of mesoscale circulation patterns, upwelling, shoaling bottom topography, and 

diel vertical migration created these large patches. These findings indicate that these sites are not 

likely an area where euphausiids would concentrate, and hence not likely a priority feeding ground for 

their pelagic predators. 

Reese et al. (2005) examined the community structure, spatial distribution patterns, and environmental 

associations of near-surface zooplankton in summer 2000. Near-surface zooplankton are an important 

food resource for the early life history stages of many fish. Generally, zooplankton assemblages are 
Appendix A, Yaquina ODMDS Evaluation/EA A-3

affected by water temperature, nutrient concentration, and salinity. The authors sampled from 

Newport, Oregon, to northern California. The authors found that during August, higher zooplankton 

concentrations are concentrated offshore whereas in June, zooplankton were concentrated more along 

shore. In addition, near-surface (Neuston net frame with a height of 0.3 meters was towed at the 

surface) zooplankton concentration was relatively low compared to subsurface estimates. The authors 

believe this occurred because all of their sampling took place during the day when it is likely 

zooplankton are found at deeper depths. In terms of species, the authors found that the most common 

groups of zooplankton in their tows were: crab megaloae, hyperiid amphipods, euphausiids, and 

chaetognaths. For the zooplankton species captured, their distribution was most explained by sea 

surface temperature. For the area sampled, the nearshore area off of Newport did not appear to have a 

particularly high concentration of zooplankton (number of individuals per cubic meter) nor did that 

area have high species richness for the sampling efforts in either June or August 2000. 

Brodeur et al. (2008) studied the spatial and trophic overlap of two dominant jellyfish and pelagic 

finfish in August 2002 between Newport, Oregon and Northern California. They sampled as close to 

shore as 3 nautical miles. They found that in spring, pelagic fishes have a greater impact on plankton 

populations whereas by late summer the opposite is true; jellyfish become the dominant zooplankton 

consumer in the system consuming almost twice as much zooplankton production as forage fishes. 

Ichthyoplankton 

Fish larvae are a transient member of the inshore coastal plankton community. Their abundance and 

distribution has been described by Richardson (1973), Richardson and Pearcy (1977), and Richardson 

et al. (1980). In more recent studies, Auth and Brodeur (2006) examined the species composition, 

distribution, and concentration of ichthyoplankton along the Newport hydrographic line from 9 to 84 

km (central Oregon coast) to investigate annual, seasonal, vertical, and cross-shelf variability. Larval 

concentrations were also analyzed in relation to water temperature and salinity. The 281 samples 

collected from five cruises between April and September in 2000 and 2002 yielded 4,944 fish larvae 

comprising 72 taxa in 28 families. The dominant taxa collected were northern anchovy (Engraulis 

mordax), slender sole (Lyopsetta exilis), rockfishes (Sebastes spp.), northern lampfish (Stenobrachius 

leucopsarus), and blue lanternfish (Tarletonbeania crenularis). Total larval concentration increased 

from 49.3 per 1000 cubic meters (m3

) in 2000 to 72.0 per 1000 m3 in 2002, with seasonal 

concentrations highest in August 2000 (90.3 per 1000 m3

) and April 2002 (151.2 per 1000 m3). 

Relatively few larvae were found at depths greater than 100 meters, while highest larval 

concentrations generally occurred from depths of 0 to 50 meters. However, slender sole 

concentrations were highest from depths of 50 to 100 meters. Larval diversity and concentration were 

higher offshore (46-84 km) than in coastal areas (9-28 km). Highest concentrations were normally 

found at an intermediate station 65 km off the coast. Species designated as either coastal or offshore 

species by previous studies were predominantly found in their respective shelf regions. With the 

exception of slender sole, larval concentrations were positively correlated with temperature and 

negatively correlated with salinity. 

Auth et al. (2007) examined diel vertical distribution, concentration, and community structure of 

ichthyoplankton from a single station 69 kilometers off Heceta Head on the central Oregon coast. The 

depth-stratified samples yielded 1,571 fish larvae from 20 taxa, representing 11 families, and 128 fish 

eggs from 11 taxa within 9 families. Dominant larval taxa were rockfishes, northern lampfish, and 

blue lanternfish. The dominant egg taxa were Pacific sardine (Sardinops sagax), medusafish 

(Icichthys lockingtoni), Pacific viperfish (Chauliodus macouni), and Pacific jack mackerel (Trachurus 

symmetricus). Larval concentrations generally increased from the surface to 50 meters, and then 

decreased with depth. Larval concentrations were higher at night than during the day, and there was 

evidence of larval diel vertical migration. Depth stratum was found to be the most important factor 
Appendix A, Yaquina ODMDS Evaluation/EA A-4

explaining variability in larval and egg concentrations. The authors noted that species composition, 

assemblages, and dominant taxa were similar to those found in other studies conducted during the 

summer off the central Oregon coast (Richardson 1973; Richardson and Pearcy 1977; Brodeur et al. 

1985; Auth and Brodeur 2006). This similarity provides evidence to support the hypothesis of Auth 

and Brodeur (2006) that past ichthyoplankton sampling along the Newport hydrographic line during 

summer is representative of ichthyoplankton assemblages elsewhere along the Oregon coast. 

Both of the aforementioned studies were conducted further offshore than the North and South 

ODMDS but likely the findings in Auth and Brodeur (2006) regarding the coastal areas (9 to 28 km) 

can be applied in terms of adults spawning mainly near the coast and the eggs and larvae get carried 

offshore by surface flows associated with coastal upwelling. Coastal spawning fish include osmerids 

(smelts), sculpins, greenlings, and some flatfishes including butter sole, English sole, sand sole. The 

authors results corroborated other findings that there is a peak spring and fall spawning seasons (high 

diversity of ichthyoplankton observed in April and September). 

BENTHIC INVERTEBRATES

Benthic invertebrates play an important role in secondary productivity in nearshore marine systems. 

They are prey items for many demersal fishes, breakdown organic material, and act as key players in 

bioturbation (mixing of sediment particles) of the top few centimeters of the seafloor. 

Benthic Infaunal Studies by USACE and EPA (1984-1989) 

Benthic infaunal studies were conducted within 3 nautical miles of Yaquina Bay in March 1984, May 

1986, October 1989, May and September 1999, and June and September 2000. Most of the studies 

were done in conjunction with the ODMDS program. In 1984, 9 stations were sampled in the vicinity 

of the Interim Site to characterize the benthic resources. In 1986 and 1989, 14 and 12 stations, 

respectively, were sampled to the west and north of the Interim Site to aid in establishing a new site. 

In 1999, 17 stations were sampled that were further west and to the north and south of the previous 

stations. In 2000, 20 stations were sampled to evaluate the proposed North and South ODMDS, which 

were located further offshore than previous sampling. 

The invertebrate fauna collected during these studies were typical of the nearshore, high-energy 

environment found along the Oregon coast. It was similar to the communities found near other 

disposal sites along the Oregon coast, such as Coos Bay sites E and F, Rogue River, Siuslaw River and 

Chetco River (Hancock et al. 1981; USACE 1985, 1988a,b). The community was dominated by 

highly mobile organisms that are adapted to a shifting sand environment. Dominant species and 

groups included gammaridean amphipods, sand dollars (Dendraster eccentricus), surface-dwelling 

gastropods (Olivella spp.) and various species of polychaete worms. 

Invertebrate diversity was fairly constant at comparable stations throughout these studies with the 

exception of one 1986 station south of the Interim Site. Because this station had a rocky and coarseshell substrate, it had a more diverse and different species composition than the sandy substrate 

stations. The dominant molluscs in these studies were the carnivorous gastropod Olivella spp. Three 

species of Olivella occur along the Oregon coast, two of which, O. biplicata and O.pycna, were 

collected off Yaquina Bay. Both of these species were present in significant numbers during 1984, 

1986 and 1989 studies. 

Dominant species of gammaridean amphipods included Mandibulophoxus gilesi, Synchelidium 

shoemakeri, and Psarnrnonyx longimerius. These amphipods are scavengers and feed primarily on 

particles of organic debris found in the sediment. M. gilesi and another species, Eohaustorius 
Appendix A, Yaquina ODMDS Evaluation/EA A-5

sencillus, showed a great deal of variability between stations and over time. The variability seen in 

these studies appears normal when compared to other studies (Hancock et al., 1981; USACE 1985, 

1988a,b). 

Benthic Invertebrate Studies by USACE and EPA (1999-2000) 

Baseline studies for the North and South sites occurred in 1999 and 2000 followed by surveys in 2002 

and in 2008 during the disposal season. These studies included bathymetry, sidescan sonar, benthic 

grabs, and benthic trawl surveys. For the 1999 and 2000 surveys, the USACE took five replicate GrayO’Hara boxcore samples from 17 and 18 stations, respectively (Marine Taxonomic Services (2001). 

These samples were taken within and around the North and South Sites in May and September 1999 

and June and September 2000. The stations discussed here are those that are within the North and 

South Sites. The data gathered outside the designated sites are contained within Marine Taxonomic 

Services 2001 and 2003 reports and will be used in future analyses of changes to species abundance 

and diversity within and outside the disposal sites. 

North Site. The May and September 1999 and the June and September 2000 surveys were similar in 

the number of species found at each sampling location. As for individual abundance, the May and 

September 1999 survey and the June 2000 were similar in abundance while the September 2000 

abundances were orders of magnitude greater. During the September 2000 survey, there appeared a 

large recruitment of opportunistic short-lived polychaetes, (Spiophanes bombyx and Megelona 

sacculate) into the North Site. The third most abundant species was the anthozoan, Halcampoides sp, a 

species that had not previously been one of the 5 most abundant species at the sampling locations. 

Otherwise, the other species with the greatest abundances were polychaetes and a crustacean. 

The benthic infaunal species found at the North Site sampling stations that had the greatest abundance 

were the same in May 1999 (YQ1), September 1999 (YQ1), and June 2000 (YQ1). However, station 

YQ24 in June 2000 only had one species (in the top 5), in common with the other stations mentioned 

(the polychaete Nephtys caecoides). In September 2000, when benthic infaunal abundance increased 

greatly at both YQ1 and YQ24 sites, the infauna was dominated by 3 species that had not been seen in 

1999 or in June 2000 at YQ 1. These species were observed at YQ24 in June 2000 in the top 5 in the 

prior 3 surveys (1 polychaete, 1 crustacean, and 1 anthozoan). It does appear that variation in species 

and their abundance can be fairly site specific. At the two sampling stations in the North Site in June 

2000, only 1 out of the 5 most abundant species were the same at both stations. 

The 1999 and 2000 September surveys at the two stations within the North site indicated that 

dominant species (the polychaete Spiophanes bombys ) were the same at both stations. Another 

polychaete (either Nephtys sp or Magelona sp.) was second most abundant . The third most abundant 

species was either an anthozoan (Halcampoides sp.) or a polychaete (Notomastus sp), and either 

polychaetes or crustaceans filled out the rest of the top 5 most abundant species. 

The dominant mollusc genus at the North Site was the carnivorous gastropod, Olivella. Dendraster 

excentricus, sand dollar, was not found in high abundance at the North Site whereas they were a 

dominant species at the stations in the South Site. 

South Site. The May and September 1999 and the June and September 2000 surveys were similar in 

the number of species found at each sampling location. As for individual abundance, the May and 

September 1999 survey and the June 2000 were similar in abundance while the September 2000 

abundances were orders of magnitude greater. During the September 2000 survey, there appeared a 

large recruitment of opportunistic short-lived polychaetes, (Spiophanes bombyx and Magelona 

sacculate). Another species which showed up in September 2000 in high abundances but was not at 
Appendix A, Yaquina ODMDS Evaluation/EA A-6

such levels was the anthozoan, Halcampoides sp. Otherwise, the other species with the greatest 

abundance were polychaetes, a crustacean, and juvenile razor clams at one station. 

The benthic infaunal species found at the South Site stations that had the greatest abundance were very 

similar in May 1999, September 1999, and June 2000. In September 2000, when benthic infaunal 

abundance increased greatly at all stations, the infauna was dominated by 3 species that had not been 

present at high abundance in 1999 or in June 2000. These species were the same top three most 

abundant species at all 4 stations sampled in September 2000: Spiophanes bombyx, Magelona 

sacculata (polychaetes), Halcampoides sp. (anthozoan). 

In the May 1999, September 1999, and June 2000, the most abundant species was fairly consistent 

between seasons and sampling stations. Dendraster excentricus (sand dollar), Notomastus lineatus

(polychaete), Olivella pycna (gastropod), Nemerteinea sp. (ribbon worm), Nephtys caecoides

(polychaetes), and Eohaustorius sencillus (crustacean) dominated the top five most abundant species. 

In general, the species abundance and diversity at each station was fairly representative of the 

community structure at the other stations. 

The large abundance increases of particular species at the both the North and South Sites in September 

2000 is postulated to have been attributed to upwelling on the Oregon coast (Marine Taxanomic 

Services 2003). Magelona sacculate and Spiophanes bombyx are two species that show a marked 

increase in the population densities in fall 2000. Most of this density increase was attributed to 

juvenile recruitment. 

Benthic Invertebrate Studies by USACE and EPA (2002) 

In June and September 2002, the USACE sampled 10 stations within the disposal area (4 stations) and 

outside the disposal area (6 stations). They took 5 replicate 0.096m2 modified Gray-O’Hara box cores 

at each of the 10 stations (Marine Taxonomic Services 2003). 

When looking at the five most abundant species at each station in the disposal area versus the nondisposal areas, it appears that many of those species which were most abundant at the non-disposal 

areas were also the most abundant species in the disposal area stations (Figure A-1). In the nondisposal areas, there were 4 species (tube-dwelling worm, polychaetes, juvenile razor clams, and 

juvenile brittle stars) which were not found at the disposal stations. Conversely, there were 3 species 

which were found at the disposal areas but were not found at the non-disposal areas (polychaetes). 

From the August 2002 sampling, the benthic infaunal assemblages at the disposal and non-disposal 

areas were dominated by 11 species (Figure A-1). Eight of those eleven species were found at the 

disposal and non-disposal areas. Of the three species that were not found at both the disposal and nondisposal areas, the non-disposal area had two polychaetes which were not found at the disposal area. 

Conversely, the tube-dwelling filter feeder (Phylum - Phoronida) was found at the disposal area and 

not at the non-disposal areas. 
Appendix A, Yaquina ODMDS Evaluation/EA A-7

Figure A-1. June and August 2002. The frequency of occurrence of the top five most abundant species 

at the stations within the disposal area (total of 4 stations sampled) and at stations in non-disposal 

areas (total of 6 stations sampled). 
Appendix A, Yaquina ODMDS Evaluation/EA A-8

Benthic Invertebrate Studies by EPA and USACE (2008) 

The most recent study of benthic infauna in support of EPA and USACE site designation at Yaquina 

was conducted in June and August 2008 by the EPA. The sampling stations were selected based on 

the previous sampling efforts in 1999, 2000, and 2002 (USACE and EPA 2011; Figure A-2). In 2008, 

the USACE disposed of dredge material before and after sampling. The USACE disposed of 135,918 

cubic yards (cy) of material at the North ODMDS drop zone over 18 days between May 20 to August 

6 (Table A-1). Thus, disposal of material occurred 10 days prior to the June 2008 sampling1

. For the 

August 2008 data, material was disposed at the North Site 19 days prior to sampling. 

June 2008 Survey 

The June 2008 survey was composed of 20 samples (18 samples plus two duplicate samples) that 

generated 6,028 specimens (Marine Taxonomic Services 2009). The dominant species in the June 

2008 data set included the polychaetes Chaetozone nr. setosa, Magelona sacculata, Nephtys 

caecoides, Onuphis iridescens, Spio filicornis, and Spiophanes bombyx; the crustaceans Anchicolurus 

occidentalis and Eohaustorius estuarius; and the miscellaneous phylum nemertinea. The number of 

polychaetes, specifically Spiophanes bombyx at a count of 3,313, far exceeded the number of other 

individual organisms. There were a total of 106 taxa of which 46 were polychaetes, 34 were 

crustacean, 18 were mollusca, 3 were echinoderms, and 5 were miscellaneous groups. No Cancer 

magister (Dungeness crab) larvae or juveniles were collected. 

In terms of number of species and density of individuals per grab between the disposal area (also 

referred to as the North ODMDS drop zone) and non-disposal areas, the disposal area had fewer 

species (M = 25; SD = 2; n = 5) and a lower density of individuals (M= 118 individuals/grab ; SD = 

28) than at non-disposal stations (M= 33 species; SD = 8, n=15; M= 362 individuals/grab ; SD = 197; 

n=15 (Figure A-3 and Tables A-2, A-3). The species that differed the most between the disposal area 

and non-disposal areas was polychaetes. Both the overall lower density of individuals and lower 

density of polychaetes at the disposal area was expected because dredged material was deposited 

during the week prior to the June sampling. Thus, these values can be considered to represent what 

occurs to the species and number of individuals immediately after a disposal event. This would 

indicate that the disposal action had an effect of lowering the number of benthic infaunal individuals, 

at least immediately (10 days) after disposal; the impact to the number of species after a disposal event 

is less clear. 

 

1

 June 2008 benthic grabs occurred on June 4 and 5. The August 2008 benthic grabs and trawl survey occurred 

on August 25. 
Appendix A, Yaquina ODMDS Evaluation/EA A-9

Figure A-2. 2008 Sampling Stations at Yaquina ODMDS 

Source: USACE and EPA 2011. 

Table A-1. Disposal Activities at North ODMDS Drop Zone Prior to Sampling 

Year Month Start 

Day 

End 

Day 

# of 

Loads 

Average cy 

per Load 

Total cy per 

Disposal Period 

2007 October 20 29 40 978 39,113 

2008 May 20 25 38 966 36,707 

2008 July 26 31 49 994 48,704 

2008 August 1 6 52 971 50,507 
Appendix A, Yaquina ODMDS Evaluation/EA A-10

Figure A-3. Average Number of Individuals and Species in Disposal Area and Non-Disposal Areas, 

June 2008 
Appendix A, Yaquina ODMDS Evaluation/EA 

Table A-2. Number of Benthic Species per Sampling Location, June 2008 

Station Polychaetes Molluscs Crustacea Nemertina Echinodermata Phoronida Misc Spp Richness Mean 

Number of Species 

North ODMDS Drop Site 

YQ-28 7 3 11 1 1 0 0 23 

25 

YQ-23 9 3 11 1 1 1 0 26 YQ-24 8 3 13 1 0 0 0 25 

YQ-24D 11 6 7 1 2 1 0 28 

YQ-25 9 2 9 1 1 1 1 24 

Background Stations – Southern part of North ODMDS 

YQ-02 13 5 11 1 0 1 0 31 

YQ-02D 15 5 6 1 1 1 0 29 34 

YQ-01 12 6 20 1 2 1 0 42 

Background Stations – South ODMDS 

YQ-13 13 5 13 1 1 1 0 34 

30 

YQ-14 13 6 13 1 1 0 1 35 YQ-29 14 6 10 1 1 1 0 33 YQ-16 6 5 9 1 1 1 0 23 YQ-17 12 6 5 1 1 1 0 26 YQ-18 11 4 9 1 1 0 1 27 

Background Stations – Outside of ODMDSs 

YQ-26 15 4 12 1 1 1 1 35 

35 

YQ-22 32 6 11 1 2 1 2 55 YQ-06 17 5 12 1 1 1 0 37 YQ-10 11 5 11 1 0 1 0 29 YQ-20 12 7 6 1 1 1 0 28 YQ-27 8 6 9 1 2 1 0 27 
Appendix A, Yaquina ODMDS Evaluation/EA 

Table A-3. Number of Benthic Individuals per Sampling Location, June 2008 

Station Polychaetes Molluscs Crustacea Nemertina Echinodermata Phoronida Misc 

Total # of 

Individuals 

per Grab 

Average # o

Individuals 

per Grab 

Number of Individuals 

North ODMDS Drop Site 

YQ-28 39 4 24 10 3 0 0 80 

118 

YQ-23 80 6 40 14 1 1 0 142 YQ-24 28 5 49 43 0 0 0 125 

YQ-24D 38 16 21 65 3 1 0 144 

YQ-25 41 2 29 18 1 7 1 99 

Background Stations – Southern part of North ODMDS 

YQ-02 438 8 41 26 0 1 0 514 

388 

YQ-02D 403 15 14 21 1 8 0 462 

YQ-01 69 13 93 6 4 2 0 187 

Background Stations – South ODMDS 

YQ-13 66 7 78 18 9 1 0 179 

386 

YQ-14 341 16 53 40 4 0 2 456 YQ-29 372 16 37 32 2 3 0 462 YQ-16 28 7 17 22 1 2 0 77 YQ-17 250 9 9 20 1 3 0 292 YQ-18 748 41 32 25 1 0 2 849 

Background Stations – Outside of ODMDSs 

YQ-26 364 17 44 16 1 2 1 445 

325 

YQ-22 312 11 52 94 2 1 1 473 YQ-06 275 11 62 14 1 5 0 368 YQ-10 72 7 25 13 0 1 0 118 YQ-20 275 25 27 7 1 1 0 336 YQ-27 132 9 16 49 3 1 0 210 
Appendix A, Yaquina ODMDS Evaluation/EA A-13

August 2008 Survey

The August 2008 survey was composed of 19 samples (18 samples plus one duplicate) that generated 

5,372 specimens (Marine Taxonomic Services 2009). The data show a high energy benthic 

community structure. The dominant species in the data set included the polychaetes Magelona 

sacculata, Spiofilicornis and Spiophanes bombyx; the mollusca Siliqua sp. juvenile (razor clam); the 

crustacea Anchicolurus occidentalis, Diastylopsis dawsoni and Photis sp. indeterminate; and the 

miscellaneous phylum nemertinea. As in June, the count of Spiophanes bombyx exceeded the number 

of other individual organisms. There were a total of 98 taxa of which 45 were polychaetes, 29 were 

crustacea , 20 were mollusca, 2 were echinoderms, and 2 were miscellaneous groups. There were four 

Dungeness crab larvae or juveniles collected. Juvenile razor clams encountered during this study were 

too immature to identify to the species level. No adult razor clams were collected because they live 

deeper in the sediment than the grab sampler could penetrate. 

In terms of number of species and density of individuals per grab between the disposal area (also 

referred to as the North ODMDS drop zone) and non-disposal areas, the disposal area had fewer 

species (M = 26; SD = 7; n = 4) and a lower density of individuals (M= 149 individuals/grab ; SD = 

55) than at non-disposal stations (M= 33 species; SD = 5, n=15; M= 318 individuals/grab ; SD = 142; 

n=15 (Figure A-4 and Tables A-4, A-5). This may indicate that the disposal action has an effect of 

lowering the number of benthic infauna. As in June, there were fewer polychaetes at the disposal area. 

Again, polychaetes were often the most numerous organisms, while molluscs, crustaceans and 

nemerteans appear to be close to equally balanced among all sites. 

Density of Benthic Invertebrates

For both June and August 2008, the density of benthic invertebrates generally increased from east to 

west, from shallow to deeper waters (Figures A-3 and A-4). For both June and August, one exception 

was sample YQ-20 (furthest west outside South ODMDS), which had a lower density than the nearest 

sample to the east (YQ-18). Sample YQ-18 had the greatest density of benthic invertebrates in June, 

while YQ-22 (furthest west outside North ODMDS) had the greatest density in August. 
Appendix A, Yaquina ODMDS Evaluation/EA A-14

Figure A-4. Average Number of Individuals and Species in Disposal Area and Non-Disposal Areas, 

Aug 2008 
Appendix A, Yaquina ODMDS Evaluation/EA 

Table A-4. Number of Benthic Species per Sampling Location, August 2008 

Station Polychaetes Molluscs Crustacea Nemertina Echinodermata Phoronida Misc Spp Richness Mean 

Number of Species 

North ODMDS Drop Site 

YQ-28 7 5 8 0 1 0 0 21 

26 YQ-23 10 6 8 0 1 1 0 26 

YQ-24 12 9 13 0 1 1 0 36 YQ-25 7 4 9 1 1 0 0 22 

Background Stations – Southern part of North ODMDS 

YQ-02 16 5 10 1 1 1 0 34 

YQ-QC1 15 5 9 1 1 1 0 32 34 

YQ-01 14 4 15 1 1 1 0 36 

Background Stations – South ODMDS 

YQ-13 11 3 9 1 1 1 1 27 

32 

YQ-14 15 4 14 0 1 1 0 35 YQ-29 14 7 13 1 1 1 0 37 YQ-16 10 5 7 1 1 1 1 26 YQ-17 14 9 12 0 1 1 0 37 YQ-18 12 5 11 2 1 0 1 32 

Background Stations – Outside of ODMDSs 

YQ-26 11 2 8 1 1 1 0 24 

33 

YQ-22 22 4 7 1 1 1 0 36 YQ-06 18 6 13 1 1 1 0 40 YQ-10 12 7 14 1 1 1 0 36 YQ-20 15 8 5 1 1 1 0 31 YQ-27 11 6 12 1 1 1 0 32 
Appendix A, Yaquina ODMDS Evaluation/EA 

Table A-5. Number of Benthic Individuals per Sampling Location, August 2008 

Station Polychaetes Molluscs Crustacea Nemertina Echinodermata Phoronida Misc Total # of Individuals Mean 

Ind

p

Number of Individuals 

North ODMDS Drop Site 

YQ-28 37 18 46 11 0 0 0 112 

149 

YQ-23 151 14 23 14 0 1 0 203 YQ-24 37 46 39 66 0 1 0 189 YQ-25 36 21 31 2 2 0 0 92 

Background Stations – Southern part of North ODMDS 

YQ-02 146 19 55 7 3 1 0 231 

175 

YQ-QC1 92 12 33 9 3 2 0 151 

YQ-01 68 11 55 7 1 2 0 144 

Background Stations – South ODMDS 

YQ-13 99 13 28 18 3 2 1 164 

335 

YQ-14 192 36 43 25 0 1 0 297 YQ-29 256 37 66 47 3 1 0 410 YQ-16 169 8 30 20 1 2 1 231 YQ-17 243 36 89 41 0 4 0 413 YQ-18 362 25 87 14 4 0 1 493 

Background Stations – Outside of ODMDSs 

YQ-26 181 8 49 11 1 6 0 256 

374 

YQ-22 485 19 107 29 1 2 0 643 YQ-06 193 37 85 17 2 3 0 337 YQ-10 93 16 74 15 1 3 0 202 YQ-20 296 42 35 18 1 1 0 393 YQ-27 312 14 49 29 2 5 0 411 
Appendix A, Yaquina ODMDS Evaluation/EA A-17

Figure A-5. Density of Benthic Invertebrates, June 2008 (number per m2) 

Source: USACE and EPA 2011. 
Appendix A, Yaquina ODMDS Evaluation/EA A-18

Figure A-6. Density of Benthic Invertebrates, August 2008 (number per m2) 

Source: USACE and EPA 2011. 
Appendix A, Yaquina ODMDS Evaluation/EA A-19

Summary 

The benthic infaunal information collected by EPA and the USACE for the baseline studies in 1999 

and 2000 and subsequent surveys of disposal and non-disposal areas in 2002 and 2008 provide 

snapshots of the infaunal community within and outside the disposal areas. The surveys show that that 

the species within and outside the disposal areas are typical inhabitants of sandy substrate at these 

depths (112 to 152 feet). Even though EPA and the USACE have not conducted year-round sampling, 

the recent findings in OWET 2011 provide insight into what may be found at these disposal sites 

besides in June and September. They found that benthic invertebrates did not vary across seasons 

which would indicate that the infaunal organisms that were found at the disposal sites prior to disposal 

and those that were found during the 2002 and 2008 sampling at non-disposal locations are likely 

typical of what benthic infaunal community structure is present year-round. Based on the benthic 

infaunal data in 2008, it appears that there may be a decrease in the number of individuals in the 

benthos post-disposal, however the number of species does not appear to be affected. In addition, the 

effect appears to be localized to the dredge disposal site itself which is a discrete area each year. Given 

the continuation of prey resources at the Site post-disposal and the relatively small area of sandy 

substrate that disposal occurs on each year, it is not likely the effects on benthic infauna translate into 

an adverse effect on prey resources for benthic feeding fish or epibenthic invertebrates. 

FISH AND EPIBENTHIC INVERTEBRATE SPECIES

The nearshore area off Yaquina Bay supports a variety of pelagic and demersal fish species and 

epibenthic invertebrate species. Bottom habitats include sand, gravel, pebbles, and rocky reefs. The 

neritic reefs off Yaquina Bay are a unique feature of the coast and are associated with bull kelp 

(Nereocystis leutkeana) beds. 

Pelagic fish species found in the nearshore ocean off of Yaquina River (Figure A-7) include 

anadromous salmonids such as coho salmon (Oncorhynchus kisutch), winter steelhead (Oncorhynchus 

mykiss), and spring and fall Chinook salmon (Oncorhynchus tshawytscha). Other pelagic species 

include the Pacific herring (Clupea harengus pallasi), northern anchovy (Engraulis mordax), and surf 

smelt (Hypomesus pretiosus). 

Demersal fish species present in the nearshore area are mostly residents and include a number of 

sculpins, sea perch, and rockfish species associated rocky habitats, as well as flatfish species occurring 

predominantly over open sandflats. Flatfish include English sole (Parophrys vetulus), sanddab 

(Citharichthys sp.), and starry flounder (Platichthys stellatus). English sole and starry flounder, along 

with the sand sole (Psettichthys melanostictus), spawn in the inshore area in the summer and juveniles 

of these, as well as other marine species, may rear in Yaquina Bay. 

The commercially and recreationally important epibenthic invertebrate species off of Yaquina Bay 

include shellfish and Dungeness crab (Cancer magister) (Figures A-8 and A-9). Razor clam beds are 

located north and south of the jetties along the beach. Recruitment to the inshore beaches comes from 

the subtidal spawning areas. Gaper clams are present in large numbers near the mouth and upriver in 

the estuary proper. Cockles are also present in the intertidal areas near the base of the jetties. Piddock 

clams occur in the sandstone outcroppings north of the estuary mouth. 

Dungeness crab adults occur on sandflat habitat along the entire Oregon coast. They spawn in 

offshore areas and occur in the estuary when conditions are favorable in late summer and fall. There 

are currently no known squid spawning areas offshore of Yaquina Bay. 
Appendix A, Yaquina ODMDS Evaluation/EA A-20

Figure A-7. Fishery Resources 
Appendix A, Yaquina ODMDS Evaluation/EA A-21

Figure A-8. Commercial and Recreational Shellfish 
Appendix A, Yaquina ODMDS Evaluation/EA A-22

Figure A-9. Commercial and Recreational Dungeness Crab 
Appendix A, Yaquina ODMDS Evaluation/EA A-23

August 2008 EPA Trawl Survey 

Seven trawl transects were conducted by EPA in August 2008 (USACE and EPA 2011) to provide a 

snapshot of the fish and epibenthic invertebrates that are found at the North ODMDS, South ODMDS 

(non-disposal), and outside the ODMDS (Figure A-10). The survey conducted two trawls at the North 

ODMDS and baseline area, but conducted three trawls at the South ODMDS. For the purposes of this 

discussion, the last trawl at the South ODMDS is not included; however, the data can be seen in the 

Attachment to this appendix. Disposal at the North ODMDS site occurred 18 days between May and 

August, with the most recent disposal being 20 days prior to the trawl survey. Information collected 

on each trawl included the number and relative age of demersal fish species; number, sex and size of 

Dungeness crab, and the number and the species of epibenthic invertebrates collected for each of the 

seven trawls. 

In total, 840 epibenthic fish were caught and all species were typical for nearshore habitat of the 

Oregon coast (Table A-6 and Attachment). The number of fish collected per trawl ranged from 95 

individuals in the North ODMDS to 177 individuals (outside of ODMDS). The number of species 

ranged from 8 species (South ODMDS) to 15 species (outside of ODMDS). Overall, the number of 

fish collected from North ODMDS trawls (146 and 95 individuals, respectively) were comparable to 

the number of fish collected from baseline trawls (104, 156, 83, 158, and 177 individuals). The 

number of species collected at North ODMDS trawls (10 and 10 species, respectively) also was 

comparable the other trawl sites (8, 10, 9, 11, and 15 species). The percent of the total catch was 

highest north of the North ODMDS site at 17 and 19%. The North ODMDS trawls pulled in 16% and 

10% of the total catch, while the trawls in the South ODMDS pulled in 9%, 11%, and 17% of the total 

catch. 

With regards to average abundance of fish per trawl, trawl YQB-05 (north of the North ODMDS) had 

the greatest number of individual fish collected during each trawl (158 and 177 individuals) with an 

average of 168 fish per trawl. These trawls also caught the greatest number of species (11 and 15 

species). The trawls within the North ODMDS averaged 121 individual fish per trawl (146 and 95, 

respectively). The trawls at the South ODMDS site averaged 130 fish per trawl (104 and 156 

individuals, respectively). The number of species per area did not appear to differ substantially with 

the range of species from 8 to 15 species (South ODMDS and north of North ODMDS). 

The fish species found during this survey likely represent the fish that are present at the Site during the 

summer, and not throughout the entire year (OWET 2011). This survey also found that high densities 

of flatfish characterized the summer trawls while flatfish densities were significantly lower in October. 

The most abundant species of benthic fish which were caught in the OWET study were similar to the 

fish species that dominated the catch in the EPA 2008 trawls. Overall, the OWET 2010 study provides 

additional data that EPA and the USACE can use as baseline and reference stations for future studies 

because of sampling conducted at the same depth and grain size. 

Juvenile Fish 

Juvenile fish were caught in all the trawls. Of all the identifiable fish caught, 75% were juveniles. 

North of the North ODMDS, 13 of the 17 (76%) species caught had at least one juvenile individual in 

the catch. In the North ODMDS, 7 of the 15 species (47%) caught had at least one juvenile individual 

collected in the survey. In the South ODMDS, 9 out of the 12 species (75%) caught had a least one 
Appendix A, Yaquina ODMDS Evaluation/EA A-24

juvenile life history stage present. In terms of which species had the most juveniles present, butter 

sole and English sole were in the top three for most juveniles present in each area. The third species 

was either the Pacific tomcod (north of North ODMDS) or Pacific sanddab (North ODMDS and South 

ODMDS). These numbers demonstrate the use of the site by juvenile benthic fish. Overall, it appears 

that the North drop zone location does not likely support significantly different abundance of adult or 

juvenile fish in comparison to comparable areas not used for dredge material disposal. 
Appendix A, Yaquina ODMDS Evaluation/EA A-25

Figure A-10. Trawl Locations at Yaquina Ocean Disposal Sites, August 2008 

 Source: USACE and EPA 2011 
Appendix A, Yaquina ODMDS Evaluation/EA A-26

Table A-6. Summary of Fish Data for Each Trawl Area, August 2008 

Common Name North of North ODMDS North ODMDS South ODMDS 

Adult Juvenile UD Adult Juvenile UD Adult Juvenile UD 

Big skate 1 4 2 1 1 

Butter sole 7 59 2 29 2 32 

Curl fin 1 

English sole 6 75 3 80 12 53 

Ling cod 1 

Pacific sanddab 6 22 27 41 59 51 

Pacific staghorn 

sculpin 6 2 1 2 

Pacific tomcod 91 13 4 

Petrale sole* 1 1 1 2 

Pricklebreast 

poacher 1 

Rock sole 1 

Sablefish 2 

Sand sole 4 25 2 19 5 22 

Showy snailfish 1 3 

Smelt - unknown sp 1 6 

Snailfish (marbled?) 1 

Speckled sanddab 7 1 

Spotted ratfish 1 1 

Starry flounder 1 1 1 

Tubenose poacher 1 4 

Warty poacher 11 9 1 6 

Unidentified sculpin 1 

Total 44 285 6 54 185 2 98 166 0 

Total # Individuals 

per Area 335 241 264 

% of Total Catch 40 29 31 

 UD = Life stage undetermined 

Dungeness Crab

Dungeness crab data provides support for the trends seen in the demersal fish data, as expected, since 

they were collected from the same trawls. The greatest number of crabs was collected from trawls 

north of the North ODMDS with totals of 17 and 30 crabs (Table A-7). The North ODMDS trawls 

had 6 and 9 adult crabs per trawl while the South ODMDS trawls collected 3, 5, and 6 adult crabs. No 

female crabs were collected at the South ODMDS while only 1 was collected at the North ODMDS. 

The trawls to the north of the North ODMDS collected the most female crabs (6 and 8 females). 

The percentage of legal male Dungeness crab (>5.75 inches) was highest in the trawls collected at the 

South ODMDS. Although there was nearly the same number of legal males north of the North 

ODMDS, they made up a smaller percentage of the overall catch than the percentage of legal males at 

trawls in South ODMDS. Overall, there was a total of 82 Dungeness crab collected of which 38% 

were legal males. 
Appendix A, Yaquina ODMDS Evaluation/EA 

Table A-7. Dungeness Crab Trawl Data, August 2008 + Legally harvestable crabs are males greater than 5.75 inches, approximately 14.7 cm (data collected in cm). ++ Percent legal males relative to the total number of crabs. NA = Not available 

Location North ODMDS South ODMDS O

Trawl 

YQB-01 

N to S in 

North ODMDS, 

Western third 

YQB-02 

S to N in 

North ODMDS, 

Eastern edge 

YQB-03 

N to S in 

South ODMDS, 

Western third 

YQB-04 

N to S in 

South ODMDS, 

Eastern third 

YQB-04 

S to N in 

South ODMDS, 

Eastern third 

YQB-05 

SW to NE 

North of 

North ODM

Replicate 1 1 1 1 2 1 

Crab Data No. 

Mean 

Width No. 

Mean 

Width No. 

Mean 

Width No. 

Mean 

Width No. 

Mean 

Width No. 

Me

Wid

cm in cm in cm in cm in Cm in cm 

Female Crabs 0 NA NA 1 14.5 5.7 1 15.2 6.0 0 NA NA 0 NA NA 6 12.4 Male Crabs 6 14.3 5.6 8 14.2 5.6 6 15.8 6.2 5 15.8 6.2 8 15.9 6.2 11 14.1 Total Crab Count 6 9 7 5 8 17 

+ No. Legal Males 2 2 5 3 6 4 

++ % Legal Males 33.3 22.2 71.4 60.0 75.0 23.5 

 Source: USACE and EPA 2011 
Appendix A, Yaquina ODMDS Evaluation/EA A-28

Epibenthic Invertebrates

The trawls collected 10 different types of epibenthic invertebrates with only Dungeness crab and 

short-spined pink star (Pisaster brevispina) collected in all trawls (Table A-8). The most numerous 

organisms were the Dungeness crab and sea nettles which were caught in the trawls north of the North 

ODMDS. Average number of individuals per area that were caught puts the area north of the North 

ODMDS with the most (47), followed by the South ODMDS (24) and then the North ODMDS (21). 

Table A-8. Epibenthic Invertebrate Data, August 2008 

Location North of North 

ODMDS North ODMDS South ODMDS 

 Trawl YQB-05 YQB-01 YQB-02 YQB-03 YQB-04 

 Replicate 1 2 1 1 1 1 2 

Common Name Latin Name 

Clear jellyfish unknown 2 3 10 6 

Crangon sp. 8 3 2 1 

Dungeness crab Cancer magister 17 30 6 9 7 5 8 

Flat mud star 2 1 5 1 

Short-spined pink star Pisaster brevispina 4 1 5 10 4 2 10 

Sunflower star Pycnopodia helianthoides 1 2 3 5 3 

Sand flea (adult) 1 

Luidia sp. Luidia sp. 1 

Sea nettles 24 3 

Unidentified shrimp 1 

Other 2 bits of 

sponges 

Total Individuals 

per Trawl 56 37 20 21 19 25 27 

Average # of 

Individuals per Area 47 21 24 

THREATENED OR ENDANGERED SPECIES

There are 23 threatened or endangered species protected under the Endangered Species Act that may 

occur in the nearshore area off of Yaquina Bay (Table A-9). Some of these species have a greater 

likelihood of occurrence than others based on their life history characteristics. In addition, given that 

the site designation could be in perpetuity, the likelihood that they may occur at the sites is greater and 

is included in this discussion. 

Salmonids

On February 11, 2008, the NMFS listed the Oregon Coast coho salmon Evolutionarily Significant Unit 

(ESU) as a threatened species under the Endangered Species Act [73 Federal Register (FR) 7816]. 

The listing includes all naturally spawned populations of coho salmon in Oregon coastal streams south 

of the Columbia River and north of Cape Blanco, including the Cow Creek [Oregon Department of 

Fish and Wildlife stock #37] coho hatchery program. Critical habitat also was designated. Yaquina 

Bay and River were designated as critical habitat but ocean waters were not included in this 

designation. 
Appendix A, Yaquina ODMDS Evaluation/EA A-29

Table A-9. Threatened or Endangered Species that May Occur at North and South ODMDS 

Species Listing Status Critical Habitat 

Anadromous Fish 

Oregon Coast Coho salmon 

(Oncorhynchus kisutch) T 6/20/08; 76 FR 35755 2/11/08; 73 FR 7816 

S. Oregon/N. California Coasts (O. kisutch) T 6/28/05; 70 FR 37160 5/5/99; 64 FR 24049 

Lower Columbia River Chinook 

(O. tshawytscha) T 8/15/11; 76 FR 50448 70 FR 52630; 9/2/05 

Upper Willamette River spring run Chinook 

(O. tshawytscha) T 8/15/11; 76 FR 50448 70 FR 52630; 9/2/05 

Snake River spring/summer run Chinook 

(O. tshawytscha) T 8/15/11; 76 FR 50448 64 FR 57399; 10/25/99 

Snake River fall-run Chinook (O. 

tshawytscha) T 6/28/05; 70 FR 37160 6/28/05; 70 FR 37160 

Southern Green sturgeon 

(Acipenser medirostris) T 4/07/06; 71 FR 17757 10/09/09; 74 FR 52300 

Eulachon (Thaleichthys pacificus) T 3/18/10; 75 FR 13012 10/20/11; 76 FR 65324 

Marine Mammals 

Eastern Steller sea lion 

(Eumetopias jubatus) T 5/5/1997; 63 FR 24345 8/ 27/93; 58 FR 45269 

Blue whale (Balaenoptera musculus) E 12/02/70; 35 FR 18319 Not applicable 

Fin whale (Balaenoptera physalus) E 12/02/70; 35 FR 18319 Not applicable 

Humpback whale 

(Megaptera novaeangliae) E 12/02/70; 35 FR 18319 Not applicable 

Southern Resident Killer whale 

(Orcinus orca) E 11/18/05; 70 FR 69903 11/26/06; 71 FR 69054 

Sei whale (Balaenoptera borealis) E 12/02/70; 35 FR 18319 Not applicable 

Sperm whale (Physeter macrocephalus) E 12/02/70; 35 FR 18319 Not applicable 

Marine Turtles 

Green turtle (Chelonia mydas) 

Excludes Pacific Coast of Mexico & Florida ET 7/28/78; 43 FR 32800 9/02/98; 63 FR 46693 

Leatherback turtle 

(Dermochelys coriacea) 

E 6/02/70 ; 39 FR 19320 3/23/79; 44 FR 17710 

1/16/12; 77 FR 4170 

Loggerhead turtle (Caretta caretta) T 7/28/78; 43 FR 32800 Not applicable 

Olive ridley turtle 

(Lepidochelys olivacea) ET 7/28/78; 43 FR 32800 Not applicable 

Birds 

Marbled murrelet 

(Brachyramphus marmoratus) T 10/01/92; 57 FR 45328 61 FR 26255; 05/24/1996 

Short-tailed albatross 

(Phoebastria (=Diomedea) albatrus) E 06/02/70; 35 FR 8491 None designated 

Western snowy plover 

(Charadrius alexandrinus nivosus) T 03/05/93; 58 FR 12864 70 FR 56969; 09/29/2005 

Northern spotted owl 

(Strix occidentalis caurina) T 06/26/90; 55 FR 26114 57 FR 1796; 01/15/1992 

Invertebrates 

Oregon silverspot butterfly 

(Speyeria zerene hippolyta) T 07/02/80; 45 FR 44935 45 FR 44935; 07/02/1980 
Appendix A, Yaquina ODMDS Evaluation/EA A-30

Coho are present in the Yaquina Bay offshore area as both adults and juveniles. Adults hold in the 

offshore area prior to entering the estuary to migrate up river to spawn. Juveniles rear in the nearshore 

ocean area after migrating downstream and transitioning to saltwater. Upstream migration of adult 

coho salmon ranges from August through November. Juvenile outmigration extends from April 

through June and peaks in May. 

In 2005, the Lower Columbia River coho salmon ESU was listed as threatened and includes all 

naturally spawned populations of coho in the Columbia River and its tributaries in Washington and 

Oregon, from the mouth of the Columbia up to and including the Big White Salmon and Hood Rivers, 

and includes the Willamette River to Willamette Falls, Oregon, as well as 25 artificial propagation 

programs (70 FR 37160). While migrating individuals may utilize the coastal habitat off Yaquina Bay 

for migratory purposes, they are likely to be further offshore than the ODMDS. 

Several ESUs of Chinook salmon listed in 2005 (70 FR 37160) could potentially be in the ocean area 

off of Yaquina Bay. These include the Lower Columbia River (threatened), Upper Willamette River 

spring-run (threatened), Upper Columbia River spring-run (endangered), Snake River spring/summer 

run (threatened), and Snake River fall-run (threatened). All of these ESUs have designated critical 

habitat, but critical habitat does not include ocean waters. During their ocean life history residence 

period, these species have been found off of Yaquina Bay (Weitkamp 2009). 

Eulachon

Southern DPS Pacific eulachon was listed as threatened on May 17, 2010 (75 FR 13012). Eulachon 

(commonly called smelt, candlefish, or hooligan) are a small, anadromous fish from the eastern Pacific 

Ocean. Eulachon typically spend 3 to 5 years in saltwater before returning to freshwater to spawn 

from late winter through mid spring. They occur in nearshore ocean waters and to 1,000 feet (300 

meters) in depth, except for the brief spawning runs into their natal (birth) streams. In the continental 

U.S., most eulachon originate in the Columbia Basin. Other areas in the U.S. where eulachon have 

been documented include Sacramento River, Russian River, Humboldt Bay and several nearby smaller 

coastal rivers (e.g., Mad River), and the Klamath River in California; Rogue and Umpqua rivers in 

Oregon; and infrequently in coastal rivers and tributaries to Puget Sound, Washington. Although 

eulachon migrate along the coast, little is known about their use of nearshore and marine habitat. In 

January 2011, critical habitat was proposed (76 FR 515) and does not include any ocean waters. 

According to NMFS analysis supporting their listing, the most significant threat to eulachon and their 

habitats are changes in ocean conditions due to climate change (75 FR 13018). Dredging was 

identified as a low to moderate threat primarily due to spawning-related impacts. However, impacts 

associated with dredged material disposal were not identified as a threat. Even though eulachon are 

found in nearshore waters, the potential for eulachon to be in the area during disposal is low because: 

(1) eulachon are not known to use Yaquina Bay; thus, large numbers of returning outmigrants or 

adults are unlikely to be transiting through the North and South ODMDS; and (2) disposal actions 

occur for a limited number of days per year, which limits the likelihood (in combination with the 

aforementioned reasoning) of fish coming in contact with dredged material disposal. 

Green Sturgeon

The Southern Distinct Population Segment (DPS) of green sturgeon was listed as threatened on April 

7, 2006 (71 FR 17757). Critical habitat was designated for the species on October 9, 2009 (74 FR 

52300). Green sturgeon that spawn to the north, primarily in the Klamath and Rogue rivers, constitute 

the Northern DPS, which is not federally listed. The two sturgeon DPSs were established because 

they were genetically distinct. According to NMFS analysis supporting the listing of the Southern 
Appendix A, Yaquina ODMDS Evaluation/EA A-31

DPS of green sturgeon, “The principal factor for decline of the Southern DPS is the reduction of the 

spawning area to a limited area of the Sacramento River” (71 FR 17762). The nearest spawning 

habitat is in the Sacramento River. Southern DPS green sturgeon likely occur at the Yaquina ODMDS 

as they migrate north and south to access estuaries during summer and early fall. Designated critical 

habitat for southern green sturgeon includes all U.S. coastal marine waters out to the 60 fathom depth 

bathymetry line from Monterey Bay, California north and east to include waters in the Strait of Juan 

de Fuca, Washington, which encompasses the ODMDS and all tidally influenced areas of Yaquina 

Bay up to the elevation of mean higher high water. 

Marine Mammals

There are many whale and sea turtle species in Oregon’s offshore coastal area that are federally listed 

under the Endangered Species Act. The blue, fin, sei, sperm, humpback, and southern resident killer 

whales are all federally endangered species and occur as migrants off the Oregon coast in waters 

typically farther from shore than within the Yaquina ODMDS. 

Blue whales occur off the Oregon coast in May and June, as well as August through October. Blue 

whales typically occur offshore as individuals or in small groups and winter well south of Oregon. Fin 

whales also winter far south of Oregon and range off the coast during summer. Sei whales also winter 

south of Oregon and probably occur in southward migration off the Oregon coast in late summer and 

early fall. Sperm whales occur as migrants and some may summer off the Oregon coast; they forage 

in waters much deeper than those in the nearshore area. Humpback whales primarily occur off the 

Oregon coast from April to October with peak numbers from June through August. Humpback whales 

are particularly concentrated in Oregon along the southern edge of Heceta Bank and are found 

primarily on the continental shelf and slope. The range of the southern resident killer whale during the 

spring, summer, and fall includes the inland waterways of Puget Sound, Strait of Juan de Fuca, and 

Southern Georgia Strait. Their occurrence in the coastal waters off Oregon has been documented. 

Little is known about their winter movements and range. 

Marine Turtles

The loggerhead, green, leatherback, and olive ridley sea turtles are all federally listed species and have 

been recorded from strandings along the Oregon and Washington coasts. The occurrence of sea turtles 

off the Oregon coast is associated with the appearance of albacore and jellyfish. Albacore occurrence 

is strongly associated with the warm waters of the Japanese current. Because these warm waters 

generally occur 30 to 60+ miles offshore from the Oregon coast, these sea turtle species do not 

typically occur in the nearshore area. However, because of food resources (i.e, jellyfish) that do occur 

closer to shore , NMFS designated critical habitat for the leatherback sea turtle off the coast of Oregon, 

which includes the North and South ODMDS. 

Birds

Federally listed marine birds that may be present in the Yaquina Bay offshore area include the marbled 

murrelet and short-tailed albatross. Threatened marbled murrelets are observed in small flocks or as 

individuals in the ocean throughout the year. The endangered short-tailed albatross may forage in 

open ocean areas off the coast. The Pacific coast population of western snowy plover is a federally 

threatened species that breeds in coastal areas in California, Oregon and Washington. Western snowy 

plover breeding and feeding occur on beaches rather than in open water. 
Appendix A, Yaquina ODMDS Evaluation/EA A-32

OTHER WILDLIFE

Wildlife resources in the vicinity of Yaquina Bay are shown in Figure A-9. Three species of seals and 

sea lions inhabit the Yaquina Bay coastal area. Steller sea lions, a federally threatened species, and 

harbor seals (Pusa vitulina) are year-long residents, while California sea lions (Zalophus 

californianus) are present most of the year. Steller sea lions forage at river mouths and nearshore 

areas along the Oregon coast. The closest Steller sea lion haul out site is located about 7 miles south 

of the Yaquina North Jetty (Seal Rock). Harbor seals breed in the estuary and on nearshore rocks. 

The Yaquina nearshore area and shoreline provides habitat for shorebirds, waterfowl, herons, bald 

eagles (Haliaeetus leucocephalus), hawks, and many other species of birds. Pelagic birds (e.g., 

murres, auklets, cormorants) likely use Yaquina Bay and River and adjacent waters for foraging. 

Figure A-1. Wildlife Resources 
Appendix A, Yaquina ODMDS Evaluation/EA A-33

COMMERCIAL AND RECREATIONAL FISHERIES - ECONOMICS

The major commercial and recreational fishing areas in the vicinity of the Yaquina ODMDS are 

shown in Figure A-5. Based on data from NMFS (2006) for commercial fishing, a total of 393 

vessels, all commercially registered, delivered landings to Newport in 2000. Landings were in the 

following West Coast fisheries (data shown represents landings in metric tons/value of said 

landings/number of vessels making landings; NA = not available): coastal pelagic (158/$14,203/17), 

crab (1,613/$7,474,302/99), groundfish (40,389/$9,382,966/179), highly migratory species 

(1,403/$2,626,906/180), salmon (368/$1,361,844/181), shellfish (NA/NA/2), shrimp 

(3,628/$3,240,124/38), and other species (50/$222,093/106). Newport residents owned 90 vessels in 

2000, of which 9 were a part of the Groundfish Vessel Buyback Program. Community members 

owned 69 vessels that participated in the federal groundfish fishery. In Toledo, community members 

owned 20 vessels, 15 of which participated in the federal groundfish fishery. 

Based on data from NMFS (2006) for recreational fishing, Newport had at least two outfitter guide 

businesses in 2003. Eight licensed charter vessel businesses were located in Newport. Ten licensed 

charter vessel businesses used Newport as their homeport. There were at least six sport fishing 

businesses operating in Newport. Newport has 13 licensing vendors. In 2000, the number of licenses 

sold by active agents was 4,785 at a value of $81,155. Two sport fishing license vendors were 

operating in Toledo in 2000 and a total of 906 angling licenses were sold at a total value of $15,021. 

For Newport, the 2000 recreational salmonid catch in the Ocean Boat Fishery was 1,141 Chinook 

salmon and 9,124 coho salmon. The recreational non-salmonid catch in the Ocean Boat Fishery was a 

total of 125,112 fish. The top species landed include black rockfish, blue rockfish, lingcod, Albacore 

tuna, Pacific halibut, chilipepper rockfish, California halibut, kelp greenling, yelloweye rockfish, and 

yellowtail rockfish. 

MARINE RESERVES

The State of Oregon is engaged in a process to establish a network of marine reserves as part of an 

overall strategy to manage its marine waters and submerged lands. The overall purpose is to protect, 

sustain, or restore the nearshore marine ecosystem, its habitats, and species. A marine reserve is an 

area within Oregon’s state territorial sea or adjacent intertidal area that is protected from all extractive 

activities including the removal or disturbance of living and non-living marine resources. Marine 

reserves are intended to provide lasting protection. The State is moving forward with 

recommendations by the Ocean Policy Advisory Council (OPAC) to establish marine reserves at Otter 

Rock, Redfish Rocks, Cape Perpetua, Cascade Head, and Cape Falcon. Of these, the Otter Rock 

marine reserve is the nearest site to the Yaquina North and South ODMDS. The Otter Rock marine 

reserve is located in Lincoln County between the cities of Newport and Depoe Bay, and encompasses 

approximately 1.3 square miles of nearshore waters. This marine reserve area is located about 8 miles 

north of the Yaquina North and South ODMDS. 
Appendix A, Yaquina ODMDS Evaluation/EA A-34

REFERENCES

Auth, T.D. and R.D. Brodeur. 2006. Distribution and community structure of ichthyoplankton off the 

coast of Oregon, USA, in 2000 and 2002. Marine Ecology Progress Series 319:199-213. 

Auth, T.D., R.D. Brodeur, and K.M. Fisher. 2007. Diel variation in vertical distribution of an offshore 

ichthyoplankton community off the Oregon Coast. Fish Bulletin 105:313-326. 

Brodeur, R.D., D.M. Gadomski, W.G. Pearcy, H.P. Batchelder, and C.B. Miller. 1985. Abundance and 

distribution of ichthyoplankton in the upwelling zone off Oregon during anomalous El Niño 

conditions. Estuarine Coastal and Shelf Science 21:365-378. 

Hancock, D.R., P.O. Nelson, C.K. Sollitt, and K.J. Williamson. 1981. Coos Bay Offshore Disposal 

Site Investigation Interim Report, Phase I, February 1979-March 1980. Report to the U.S. Army 

Corps of Engineers, Portland District. Oregon State University, Corvallis OR. 

Keister, J.E. and W.T. Peterson. 2003. Zonal and seasonal variations in zooplankton community 

structure off the central Oregon Coast, 1998-2000. Progress in Oceanography 57:341-361. 

Marine Taxonomic Services, Ltd. January 2009. Draft Report, Oregon Coast Ocean Dredged Material 

Disposal Site Benthic Survey. Prepared for U.S. Environmental Protection Agency Region 10, 

Seattle, WA. 

NMFS (National Marine Fisheries Service). 2006. Draft Community Profiles for West Coast and 

North Pacific Fisheries - Washington, Oregon, California, and other U.S. States. Socioeconomics 

Program, Northwest Fisheries Science Center and Economics and Social Sciences Research 

Program, Alaska Fisheries Science Center. 

OWET (Oregon Wave Energy Trust). 2011. Baseline characterization and monitoring of the OSU 

mobile ocean test berth site: Benthic habitat characteristics and organisms on the central Oregon 

Coast. 33p. www.oregonwave.org (Accessed February 2012). 

Peterson, W.T. and C.B. Miller. 1976. Zooplankton along the continental shelf off Newport, OR 1969- 

1972: distribution, abundance, seasonal cycle, and year to year variations. Oregon State 

University, Sea Grant College Program Pub. No. ORESU-T-76-002. 

Peterson, W.T. and Miller, C.B. 1977. Seasonal cycle of zooplankton abundance and species 

composition along the central Oregon Coast. Fishery Bulletin 75:717–724. 

Peterson, W.T., C.B. Miller and A. Hutchinson. 1979. Zonation and maintenance of Copepod 

populations in the Oregon upwelling zone. Deep-Sea Research 26A:467-494. 

Richardson, S.L. 1973. Abundance and distribution of larval fishes in waters off Oregon, May-October 

1969, with special emphasis on the northern anchovy, Engraulis mordax. Fishery Bulletin 71:697-

711. 

Richardson, S.L. and W.G. Pearcy. 1977. Coastal and oceanic larvae in an area of upwelling off 

Yaquina Bay, Oregon. Fishery Bulletin 75:125-145. 
Appendix A, Yaquina ODMDS Evaluation/EA A-35

Richardson, M.D., A.G. Carey and W.A. Colgate. 1977. An Investigation of the Effects of Dredged 

Material Disposal on Neritic Benthic Assemblages off the Mouth of the Columbia River. Phase II. 

USACE Portland District for Contract Number DACW57-76-R-0025. 

Richardson, S.L., J.L. Laroche and M.D. Richardson. 1980. Larval fish assemblages and associations 

in the northwest Pacific Ocean along the Oregon coast, winter-spring 1972-1975. Estuarine and 

Coastal Marine Science 11:671-698. 

USACE (U.S. Army Corps of Engineers). 1985. Yaquina Bay Interim Ocean Dredged Material 

Disposal Site Evaluation Study. Portland District, Portland OR. 

USACE. 1988a. Chetco Ocean Dredged Material Disposal Site Evaluation, Final Report. Portland 

District, Portland OR. 

USACE. 1988b. Rogue Ocean Dredged Material Disposal Site Evaluation, Final Report. Portland 

District, Portland OR. 

USACE and EPA. March 2011. 2008 Monitoring Studies at Yaquina Bay Ocean Dredged Material 

Disposal Sites (ODMDS). Final Data Report. Portland District and EPA Region 10. 

Weitkamp, L.A. 2009. Marine distribution of Chinook salmon (Oncorhynchus tshawytscha) from the 

west coast of North America determined by coded wire tag recoveries. Transactions of the 

American Fisheries Society 139:147-170. 
Appendix A, Yaquina ODMDS Evaluation/EA A-36

ATTACHMENT A 

DEMERSAL FISH DATA BY LOCATION, AUGUST 2008 

North ODMDS 

 

Trawl 

YQB-01 

N to S in North ODMDS 

Western third 

YQB-02 

S to N in North ODMDS 

Eastern edge 

 Replicate number 1 1 

Common Name Latin name Adult Juvenile UD Adult Juvenile UD 

Big skate Raja binoculata 2 1 

Butter sole Isopsetta isolepis 1 11 1 18 

Curl fin Pleuronichthys decurrens 1 

English sole Parophrys vetulus 1 50 2 30 

Ling cod Ophiodon elongatus 

Pacific sanddab Citharichthys sordidus 25 28 2 13 

Pacific staghorn sculpin Leptocottus armatus 1 

Pacific tomcod Microdadus proximus 3 10 

Petrale sole* Eopsetta jordani 1 1 

Pricklebreast poacher Stellerina xyosterna 

Rock sole Lepidopsetta sp. 

Sablefish Anoplopoma fimbria 

Sand sole Psettiethys melanostictu 2 16 3 

Showy snailfish Liparis pulchellus 3 

Smelt - unknown sp Atherinops sp. 

Snailfish (marbled?) Liparis (dennyi)? 1 

Speckled sanddab Citharichthys stigmaeus 

Spotted ratfish Hydrolagus colliei 1 1 

Starry flounder Platichthys stellatus 1 

Tubenose poacher Pallasina barbata 1 

Warty poacher Ocella verrucosa 9 1 

Unidentified sculpin 

Subtotals 35 111 0 19 74 2 

Totals 146 95 

% of Total Catch 15.9 10.3 

*The adult petrale sole from trawl YQB-01 had a 2.5 cm dorsal growth; adult fish, 3-4 years. 

UD = Life stage undetermined 

Source: USACE and EPA 2011
Appendix A, Yaquina ODMDS Evaluation/EA A-37

North of North ODMDS 

 

Trawl 

YQB-05 

SW to NE 

North of North ODMDS 

YQB-05 

N to S 

North of North ODMDS 

 Replicate number 1 2 

Common Name Latin name Adult Juvenile UD Adult Juvenile UD 

Big skate Raja binoculata 1 2 2 

Butter sole Isopsetta isolepis 4 28 3 31 

Curl fin Pleuronichthys decurrens 

English sole Parophrys vetulus 4 33 2 42 

Ling cod Ophiodon elongatus 1 

Pacific sanddab Citharichthys sordidus 1 11 5 11 

Pacific staghorn sculpin Leptocottus armatus 4 1 2 1 

Pacific tomcod Microdadus proximus 43 48 

Petrale sole* Eopsetta jordani 1 

Pricklebreast poacher Stellerina xyosterna 1 

Rock sole Lepidopsetta sp. 1 

Sablefish Anoplopoma fimbria 2 

Sand sole Psettiethys melanostictu 2 17 2 8 

Showy snailfish Liparis pulchellus 1 

Smelt - unknown sp Atherinops sp. 1 

Snailfish (marbled?) Liparis (dennyi)? 6 

Speckled sanddab Citharichthys stigmaeus 

Spotted ratfish Hydrolagus colliei 

Starry flounder Platichthys stellatus 1 

Tubenose poacher Pallasina barbata 

Warty poacher Ocella verrucosa 4 7 

Unidentified sculpin 1 

Subtotals 22 136 0 22 149 6 

Totals 158 177 

% of Total Catch 17.2 19.3 

UD = Life stage undetermined 

Source: USACE and EPA 2011
Appendix A, Yaquina ODMDS Evaluation/EA A-38

South ODMDS 

Location South ODMDS 

Trawl 

YQB-03 

N to S in South ODMDS 

Western third 

YQB-04 

N to S in South ODMDS 

Eastern third 

YQB-04 

S to N in South ODMDS 

Eastern third 

Replicate number 1 1 2 

Common Name Latin name Adult Juvenile UD Adult Juvenile UD Adult Juvenile UD 

Big skate Raja binoculata 1 1 1 

Butter sole Isopsetta isolepis 12 2 20 4 4 

Curl fin Pleuronichthys decurrens 

English sole Parophrys vetulus 4 21 8 32 26 

Ling cod Ophiodon elongatus 

Pacific sanddab Citharichthys sordidus 21 29 38 22 20 7 

Pacific staghorn sculpin Leptocottus armatus 2 

Pacific tomcod Microdadus proximus 1 3 3 

Petrale sole* Eopsetta jordani 1 1 

Pricklebreast poacher Stellerina xyosterna 

Rock sole Lepidopsetta sp. 

Sablefish Anoplopoma fimbria 

Sand sole Psettiethys melanostictu 2 10 3 12 3 7 

Showy snailfish Liparis pulchellus 

Smelt - unknown sp Atherinops sp. 

Snailfish (marbled?) Liparis (dennyi)? 

Speckled sanddab Citharichthys stigmaeus 7 1 2 

Spotted ratfish Hydrolagus colliei 

Starry flounder Platichthys stellatus 1 1 

Tubenose poacher Pallasina barbata 4 

Warty poacher Ocella verrucosa 2 4 

Unidentified sculpin 

Subtotals 30 74 0 64 92 0 32 46 5 

Totals 104 156 83 

% of Total Catch 11.3 16.9 9.0 

UD = Life stage undetermined 

Source: USACE and EPA 2011
Appendix A, Yaquina ODMDS Evaluation/EA 

ATTACHMENT B 

Yaquina ODMDS Bathymetry – August 2, 2011.