APPENDIX AIR10-C Technical Data Reports Containing Habitat Maps at Local and Regional Scales

TDR MF-2 - Marine Benthic Subtidal Study TDR

PORT METRO VANCOUVER | Roberts Bank Terminal 2 Information Request Response

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ROBERTS BANK TERMINAL 2 TECHNICAL DATA REPORT Marine Invertebrates, Marine Fish & Fish Habitat Marine Benthic Subtidal Study

Prepared for: Port Metro Vancouver 100 The Pointe, 999 Canada Place Vancouver, B.C. V6C 3T4

Prepared by: Hemmera Envirochem Inc. 18th Floor, 4730 Kingsway Burnaby, BC V5H 0C6

August 2014

Port Metro Vancouver Hemmera RBT2 – Marine Benthic Subtidal Study August 2014

Technical Report / Technical Data Report Disclaimer

The Canadian Environmental Assessment Agency determined the scope of the proposed Roberts Bank Terminal 2 Project (RBT2 or the Project) and the scope of the assessment in the Final Environmental Impact Statement Guidelines (EISG) issued January 7, 2014. The scope of the Project includes the project components and physical activities to be considered in the environmental assessment. The scope of the assessment includes the factors to be considered and the scope of those factors. The Environmental Impact Statement (EIS) has been prepared in accordance with the scope of the Project and the scope of the assessment specified in the EISG. For each component of the natural or human environment considered in the EIS, the geographic scope of the assessment depends on the extent of potential effects.

At the time supporting technical studies were initiated in 2011, with the objective of ensuring adequate information would be available to inform the environmental assessment of the Project, neither the scope of the Project nor the scope of the assessment had been determined.

Therefore, the scope of supporting studies may include physical activities that are not included in the scope of the Project as determined by the Agency. Similarly, the scope of supporting studies may also include spatial areas that are not expected to be affected by the Project.

This out-of-scope information is included in the Technical Report (TR)/Technical Data Report (TDR) for each study, but may not be considered in the assessment of potential effects of the Project unless relevant for understanding the context of those effects or to assessing potential cumulative effects.

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EXECUTIVE SUMMARY

The Roberts Bank Terminal 2 Project (RBT2 or the Project) is a proposed new three-berth marine terminal at Roberts Bank in Delta, B.C. The Project is part of PMV’s Container Capacity Improvement Program, a long-term strategy to deliver projects to meet anticipated growth in demand for container capacity to 2030.

Hemmera has been retained by PMV to undertake environmental studies related to the Project. This technical data report describes the results of the Marine Benthic Subtidal Study. Roberts Bank and the surrounding waters of the Fraser River estuary support a rich assemblage of species, some of which are of high commercial, recreational, aboriginal or ecological value. A number of these species, including Dungeness crab (Metacarcinus magister) and benthic finfish, namely flatfishes (order: Pleuronectiformes) and Pacific sand lance (Ammodytes hexapterus; PSL), have been consistently documented within the Roberts Bank study area or are expected to occur based on identified habitat preferences.

The purpose of the Marine Benthic Subtidal Study is to improve the current state of knowledge on fish and invertebrate species occurring within, and adjacent to, the proposed RBT2 footprint. Objectives include quantifying the distribution, densities, and habitat preferences of key species or species groups (listed above), and identifying sensitive life history stages. This study consists of a review of available literature and historic data, and two Project-specific field surveys: i) gravid female Dungeness crab SCUBA survey; and ii) remotely-operated vehicle (ROV) survey.

SCUBA surveys were conducted to address existing data gaps on gravid (egg-bearing) female Dungeness crab densities and habitat preferences within shallow subtidal habitat at Roberts Bank during the winter brooding season, which extends approximately from October to March. During this period, female crabs concentrate in high numbers, completely or partially burying themselves in sediment, and remain relatively inactive while brooding their embryos. SCUBA results indicate that gravid female Dungeness crabs are present within the Roberts Bank study area; however, only individual gravid female crabs (i.e., no brooding aggregations) were encountered. The majority of gravid female crabs occurred within the deepest depth zone surveyed (i.e., from −10 to −20 m relative to chart datum; CD), suggesting that females may be residing in deeper water to brood, at depths beyond the reach of safe SCUBA dive limits (≤-18 m). The densities estimated in this study are comparable to gravid female crab densities estimated in previous SCUBA surveys at locations peripheral to brooding aggregations (e.g., <0.02 crabs/m2, O’Clair et al. 1996; <1 crab/m2, Stone and O’Clair 2002). The low density of gravid female crabs within the study area may reflect sampling efforts coinciding with the end of the brooding season, rather than the period of peak aggregations.

Port Metro Vancouver Hemmera RBT2 – Marine Benthic Subtidal Study - ii - August 2014

Transect surveys completed using ROV were performed to quantitatively assess the summer distributions, densities, and habitat associations of Dungeness crabs, PSL, and flatfishes within the Roberts Bank study area. The surveys covered seabed depths greater than were accessible by benthic trawls and/or SCUBA divers (up to −40 m). Results show that depth is a major factor governing Dungeness crab density and total crab density among the surveyed locations, with highest densities occurring within the −10 to −20 m CD depth zone. Flatfish, as a group, were observed at all depths within the study area, and comprised the highest proportion of finfish observations. Flatfish density appeared to be highest within the −20 to −30 m depth zone and in coarse sand; however, no statistically significant differences were noted. ROV video imagery of flatfish species depicted consistent use of depths <−25 m, highlighting the importance of subtidal areas as flatfish habitat at Roberts Bank.

Orange sea pens (Ptilosarcus gurneyi) were not targeted as a focal species by the ROV survey, but rather as a biogenic (i.e., habitat created by a living organism) component of habitat complexity. They were the most abundant invertebrate species recorded and were widely distributed across all transect sites. Orange sea pens were observed at depths ranging from −25 to −40 m CD, extending known sea pen habitat deeper than those documented in previous studies, which were constrained by depth limitations (i.e., −35 m CD) of towed underwater video (SIMS) equipment. Results indicate that orange sea pens preferred coarse sediments over fine sediments and shallow depths (e.g., −5 to −10 m CD) over deeper areas (e.g., −20 to −30; −30 to −40 m CD) (p ≤ 0.05).

A weak negative relationship between total finfish density and sea pen density was noted (r2 = 0.013, p= 0.02), suggesting no obligatory relationship between these species; however, the functional relationships between orange sea pens and associated finfish may involve ecologically complex processes not captured in this study.

Pacific sand lance were not observed during the ROV survey, possibly due to inherent sampling limitations for PSL associated with their small size and complex life history involving alternating benthic burrowing and pelagic foraging behaviours. While their presence and the presence of suitable burying habitat for this species in the subtidal zone at Roberts Bank have been confirmed through other studies, data gaps still exist relating to abundance, densities, and extent of suitable burying habitat within the Roberts Bank study area.

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TABLE OF CONTENTS

EXECUTIVE SUMMARY ...... I 1.0 INTRODUCTION ...... 1

1.1 PROJECT BACKGROUND ...... 1

1.2 MARINE BENTHIC SUBTIDAL STUDY OVERVIEW ...... 1 2.0 REVIEW OF AVAILABLE LITERATURE AND DATA ...... 3

2.1 DUNGENESS CRABS ...... 3 2.1.1 Distribution ...... 3 2.1.2 Life History and Behaviour ...... 3 2.1.3 Habitat Requirements and Limiting Factors ...... 4

2.2 FLATFISH SPECIES ...... 6 2.2.1 Distribution ...... 6 2.2.2 Habitat Requirements and Limiting Factors ...... 6

2.3 PACIFIC SAND LANCE ...... 8 2.3.1 Distribution ...... 8 2.3.2 Habitat Requirements and Limiting Factors ...... 9

2.4 VISUALSURVEYING APPROACHES ...... 11 3.0 METHODS ...... 13

3.1 GRAVID FEMALE DUNGENESS CRAB (SCUBA) SURVEY ...... 13 3.1.1 Overview ...... 13 3.1.2 Study Area ...... 13 3.1.3 Temporal Scope ...... 13 3.1.4 Study Methods ...... 15 3.1.5 Data Analysis ...... 16

3.2 REMOTELY-OPERATED VEHICLE (ROV) SURVEY ...... 18 3.2.1 Overview ...... 18 3.2.2 Study Area ...... 18 3.2.3 Temporal Scope ...... 18 3.2.4 Study Methods ...... 20 3.2.4.1 ROV Transect Survey ...... 20 3.2.4.2 Sediment Sampling ...... 23 3.2.5 Data Analysis ...... 25

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3.2.5.1 ROV Video Analyses ...... 25 3.2.5.2 Sediment Analyses ...... 28 3.2.5.3 Statistical Analyses: Habitat Associations ...... 32 4.0 RESULTS ...... 33

4.1 GRAVID FEMALE DUNGENESS CRAB SURVEY ...... 33 4.1.1 Study Results ...... 33 4.1.1.1 Crab Observations ...... 33 4.1.1.2 Non-target Invertebrates ...... 36

4.2 REMOTELY-OPERATED VEHICLE (ROV) SURVEY ...... 37 4.2.1 Study Results ...... 37 4.2.1.1 ROV Video Analyses ...... 37 4.2.1.2 Statistical Analyses: Habitat Associations ...... 39 5.0 DISCUSSION ...... 46

5.1 DISCUSSION OF KEY FINDINGS ...... 46 5.1.1 Gravid Female Dungeness (SCUBA) Crab Survey ...... 46 5.1.2 ROV Transect Survey ...... 48 5.1.2.1 Dungeness Crabs ...... 48 5.1.2.2 Flatfish ...... 48 5.1.2.3 Finfish ...... 49 5.1.2.4 Orange sea pens ...... 50

5.2 DATA GAPS AND LIMITATIONS ...... 51 6.0 CLOSURE ...... 54 7.0 REFERENCES ...... 55 8.0 STATEMENT OF LIMITATIONS ...... 65

List of In-Text Tables

Table 1 Marine Benthic Subtidal Study Components and Major Objectives ...... 1 Table 2 Species Treatment Response Variables Measured During the ROV Survey...... 32 Table 3 Dungeness Crabs Identified During the Gravid Female Dungeness Crab (SCUBA) Survey ...... 34

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List of In-Text Figures

Figure 1 Marine Benthic Subtidal Study Area Offshore of the Roberts Bank Terminals ...... 14 Figure 2 SCUBA Dive Transect Locations for the Gravid Female Dungeness Crab Survey ...... 17 Figure 3 Remotely-Operated Vehicle Survey Transect Locations ...... 19 Figure 4 Van Veen© Sediment Sample Locations from the Remotely-Operated Vehicle Survey .. 24 Figure 5 Remotely-Operated Vehicle Transect Lines Overlying Fine Resolution Inverse Distance Weighted (IDW) Interpolation of Geometric Mean Sediment Grain Size (mm) within the Study Area ...... 31 Figure 6 Comparison of Mean Numbers of Dungeness Crabs among Depth Strata ...... 35 Figure 7 Comparison of Mean Numbers of Gravid Female Dungeness Crabs among Depth Strata ...... 36 Figure 8 Bar Plots of the Density of each Species Treatment at Various Depth Zones ...... 41 Figure 9 Bar Plots of the Density of each Species Treatment at Different Sediment Grain Size Classifications ...... 42 Figure 10 Bar Plot of the Species Treatment Densities at the Different Geographical Locations (1 to 3) along the Delta-front Slope at Roberts Bank (Figure 3) ...... 43 Figure 11 Bar Plot of Species Treatment Densities Inside and Outside of the Proposed RBT2 Footprint and Dredge Zone (DZ) ...... 44 Figure 12 Linear Regression of the Weak Negative Relationship between Orange Sea Pen Density and Total Finfish Density ...... 45

List of Appendices

Appendix A Figures

Appendix B Tables

Appendix C Photographs

Appendix D Supplementary Information

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Port Metro Vancouver Hemmera RBT2 – Marine Benthic Subtidal Study - 1 - August 2014

1.0 INTRODUCTION

This section provides Project background information and an overview of the Marine Benthic Subtidal Study.

1.1 PROJECT BACKGROUND

The Roberts Bank Terminal 2 Project (RBT2 or Project) is a proposed new, three-berth marine terminal at Roberts Bank in Delta, B.C. that could provide 2.4 million TEUs (twenty-foot equivalent unit containers) of additional container capacity annually. The Project is part of Port Metro Vancouver’s (PMV) Container Capacity Improvement Program, a long-term strategy to deliver projects to meet anticipated growth in demand for container capacity to 2030.

Port Metro Vancouver has retained Hemmera to undertake environmental studies to inform a future effects assessment for the Project. This technical data report (TDR) documents the current seasonal use of the subtidal environment at Roberts Bank by benthic invertebrate and fish species, with a specific focus on Dungeness crab (Metacarcinus magister), flatfish species (order: Pleuronectiformes), and Pacific sand lance (Ammodytes hexapterus; herein PSL).

1.2 MARINE BENTHIC SUBTIDAL STUDY OVERVIEW

A review of existing information and state of knowledge was completed for the Marine Benthic Subtidal Study to identify key data gaps and areas of uncertainty within the general RBT2 area. This TDR describes the study findings for key components identified from this gap analysis. Study components, major objectives, and a brief overview are provided in Table 1.

Table 1 Marine Benthic Subtidal Study Components and Major Objectives

Component Major Objective Brief Overview

 Document gravid female SCUBA surveys were conducted in January 2011 at Dungeness crab 12 transect locations stratified by depth (≤−18 m) 1) SCUBA presence/absence during the within the subtidal area at Roberts Bank. Survey: Gravid winter brood season. Dungeness crabs were enumerated and classified Female Crabs  Quantify gravid female Dungeness by sex. Physical habitat data was qualitatively crab depth distribution, densities, assessed and the presence of other benthic species and habitat preferences. recorded.

 Quantitatively assess summer ROV surveys were conducted in July 2013 at 12 depth distribution, abundance, and transect sites stratified by depth (−5 to −40 m) within the subtidal area at Roberts Bank. Video review was 2) Remotely- densities of three target used to identify and enumerate invertebrate and fish operated species/guilds: Dungeness crabs, species. Sediment sampling was used to vehicle (ROV) flatfishes, and PSL. supplement physical habitat data and characterise Survey  Characterise associated physical sediment grain size. Species’ habitat preference components and quantify species’ was quantitatively assessed using statistical habitat preferences. analyses.

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Roberts Bank and the surrounding waters of the Fraser River estuary support a rich assemblage of marine invertebrate and fish species (Burd et al. 2008, Archipelago 2014c), some of which are of high commercial, recreational, aboriginal or ecological value. A number of these species have been consistently documented within the Roberts Bank study area (Triton 2004, Archipelago 2014b, Hemmera 2014a), including commercially harvested Dungeness crab and benthic fish species (i.e., flatfishes and PSL), or are expected to occur based on identified habitat preferences (Robinson et al. 2013). Although these species are known to spend a portion of their life cycle in the near-shore (i.e., intertidal and shallow subtidal) benthic environment, the current state of knowledge on their abundance, distribution, and density within the subtidal habitat at Roberts Bank is limited, representing a gap in our understanding of species-specific habitat use within the study area and how it relates to the timing of different life history stages (e.g., gravid female Dungeness crabs). The purpose of this study is to document current seasonal use (i.e., timing, location, and habitat preferences) of the benthic subtidal environment at Roberts Bank by the above-listed target species.

Female Dungeness crabs exhibit seasonal patterns in subtidal habitat use and depth distribution related to brooding. During the fall-winter brooding season, gravid female Dungeness crabs are highly dependent on sandy bottom substrate, in which they bury and remain relatively sedentary (Scheding et al. 2001; Stone and O’Clair 2001, 2002). The extent of gravid female presence and use, locations of brooding ‘hotspots’, and behaviour during this sensitive life history stage are not well understood in the Roberts Bank area. To address this data gap, SCUBA surveys were employed to collect site-specific biological and physical information.

Seasonal and life history differences in subtidal habitat use are also expected for PSL and flatfish at Roberts Bank, where they play an important ecological role as prey for many higher trophic level species of fish, marine birds, and marine mammals (Sinclair and Zeppelin 2002). Although benthic fish diversity and use of shallow subtidal habitat at Roberts Bank have been previously documented through seasonal bottom trawl surveys (Archipelago 2014b), distributions and habitat preferences of juvenile and adult life stages of these fish species within deeper ranges of the subtidal (i.e., beyond the maximum depth accessible by trawls, −18 to −22 m relative to Chart Datum; CD) have yet to be investigated. To quantitatively assess summer distributions, abundances, and densities of Dungeness crab, PSL, and flatfishes at Roberts Bank at depths up to −40 m CD, remotely-operated vehicle (ROV) surveys were conducted. Additionally, sediment sampling during the ROV survey enabled quantification of physical components of the species’ habitat, including sediment type, substrate cover, and habitat complexity (i.e., emergent structures).

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2.0 REVIEW OF AVAILABLE LITERATURE AND DATA

This section provides a review of available literature and data considered in the Marine Benthic Subtidal Study.

2.1 DUNGENESS CRABS

2.1.1 Distribution

Dungeness crabs are widely distributed along the western continental shelf of North America, from the Pribolof Islands, Alaska to Santa Barbara, California (Jensen and Armstrong 1987) where they inhabit shallow coastal waters (e.g., estuaries, inlets, and bays) and open coastal habitats (Holsman et al. 2006, Rasmuson 2013). In estuarine habitats, adult Dungeness crabs generally reside in the low intertidal zone, but are also observed in deeper habitats up to −230 m (Jensen 1995, Rasmuson 2013). Because of its widespread distribution, Dungeness crabs exhibit spatial and temporal variation in microhabitat use across different populations (Rasmuson 2013).

2.1.2 Life History and Behaviour

Dungeness crab life history involves distinct stages of development, including pelagic larvae, megalopae1, instars2, older juveniles, and mature adults (Armstrong et al. 1989). Adults migrate to shallow waters in spring to reproduce, where males will embrace females and mate shortly after the female crab moults and is in a softshell state (Jensen et al. 1996). Male crabs often mate with multiple females in the same season (Orensanz and Gallucci 1988), and females can also mate with more than one male in a season (Jensen et al. 1996). Females produce two thousand to two million eggs, depending on their size, and can store sperm up to 2.5 years to fertilise their eggs when their carapace has hardened, usually in October or November (Wild 1980, Hankin et al. 1989, Rasmuson 2013). Frequency of moulting and mating appears to be related to the size of the female. In Alaska, large female crabs (>141 mm carapace width, herein CW) are limited by time required for their gonads to fully develop and therefore spawn every second year, while smaller females (<141 mm CW) moult, mate, and extrude eggs annually (Swiney et al. 2003). Eggs adhere to the abdomen and are protected and aerated by the female throughout the winter for approximately three months of embryonic development. During this time, female crabs are relatively inactive, seldom feed, and remain buried in bottom sediments (Dunham et al. 2011). Eggs hatch during late winter/early spring, depending on location (latitude) and water temperature.

Dungeness crab larvae emerge into the water as pre-zoeae, but moult quickly (within one hour) to the first zoea stage3. The planktonic stage is protracted, lasts for four to five months, and entails five zoeal stages followed by a megaloae stage; therefore, larval transport and survival are largely governed by oceanic

1 Final larval stage in decapod crustaceans where behaviour, morphology, and physiology is transitional between the larval and early juvenile stages (Brown and Terwilliger 1992). 2 Developmental stage between each moult until sexual maturity is reached. 3 Free-swimming crab larval stage

Port Metro Vancouver Hemmera RBT2 – Marine Benthic Subtidal Study - 4 - August 2014 processes and timing of phytoplankton blooms (Gunderson et al. 1990, Jamieson and Phillips 1993, McConnaughey et al. 1995, Roegner et al. 2007, Mackas et al. 2013). As megalopae approach settlement, they migrate back to near-shore environments by swimming into currents and attaching to objects drifting in the plankton, eventually settling in intertidal habitats within shallow coastal zones or estuaries (Gunderson et al. 1990, McConnaughey et al. 1992). Settlement occurs progressively later at higher latitudes, except in the Strait of Georgia, where in most years settlement extends from late June through September, peaking in August (McMillan et al. 1995). In some years, multiple pulses of settlement are reported for inland waters, corresponding to cohorts of early settling coastal stocks and later settling inland stocks (McMillan et al. 1995).

Megalopae settle into complex substrates, such as oyster shell or eelgrass beds, and metamorphose into first instar juveniles after settlement (Pauley et al. 1989). Following settlement from the plankton, juveniles are closely associated with the substrate and appear to remain in the area where they initially settle throughout the first year of life after metamorphosis (Gunderson et al. 1990). Upon reaching a carapace width of approximately 30 mm, considered a size refuge from predation, age 0+1 crabs migrate to subtidal areas (Dumbauld and Armstrong 1987, Fernandez et al. 1993).

Like other crustaceans, Dungeness crabs grow discontinuously by moulting, a process whereby the old shell is shed as a new shell underneath absorbs water, swells to a new size 15 to 30% larger, and hardens over several months. After approximately two years and more than 10 moults, juvenile crabs reach sexual maturity (DFO 2012). Published sizes at maturity are 100 mm CW for females and 120 mm CW for males (Dunham et al. 2011), and life span ranges from 8 to 10 years (DFO 2012).

2.1.3 Habitat Requirements and Limiting Factors

Dungeness crabs exhibit seasonal and diel variation in habitat preferences (e.g., depth) related to activities such as feeding or spawning. Habitat preferences vary with life-history stage. For example, juvenile crabs are most abundant in shallow (<10 m) waters closely associated with secondary refuge habitats such as gravel and rocky substrates covered in macroalgae or silt and sandy bottoms that support dense eelgrass beds (McMillan et al. 1995, Rooper et al. 2002, Burd et al. 2008). Two years of juvenile Dungeness crab studies at Roberts Bank showed that densities are highest in areas with overstories of attached or drift Ulva spp. (either filamentous Ulva hummocks or Ulva sheets), intermediate in eelgrass (native Zostera marina and non-native Zostera japonica), and lowest in open sand/mudflats (Hemmera 2014a). Similar findings for Dungeness crabs were observed in northern Puget Sound (McMillan et al. 1995). Juveniles also seek refuge in intertidal habitats with shell deposits, such as oyster beds, that support large densities of potential prey (Holsman et al. 2003).

1 0+ age class: young-of-the-year, newly settled juvenile crabs; 0 to 1 year of age 1+ age class: older juveniles and sub-adult crabs; 1 to 2 years of age 2+ age class: sexually mature adult crabs; ≥2 years of age

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Adult Dungeness crabs are most abundant on subtidal sand or mud bottoms (Cleaver 1949; Rasmuson 2013), and have been frequently and consistently documented at Roberts Bank down to depths of −25 m (Triton 2004; Archipelago 2014a, 2014b). Sub-adult (i.e., 40 to 100 mm CW) crabs are frequently found in subtidal channels during daily low tides, while adult crabs (100+ mm CW) are frequently inactive and buried in the soft sediment (McGaw 2005). Sub-adult and adult crabs migrate from these deeper refugia into intertidal habitats during nocturnal flood tides to forage for food (Gunderson et al. 1990; Fernandez et al. 1993; Holsman et al. 2003, 2006; Curtis and McGaw 2012).

Field and laboratory studies suggest that adults display physiological and behavioral stress responses to low salinity conditions below 24 practical salinity units (psu) (Curtis and McGaw 2008, 2012), and are unable to tolerate prolonged exposure to salinities below 12 psu (Cleaver 1949). Cooler temperatures and higher salinity levels associated with high tides allow adults to enter and exploit shallow sandy-bottom habitats (Curtis and McGaw 2008). Adult Dungeness crabs are also highly sensitive to fluctuations in dissolved oxygen (DO) levels in bottom waters. Although individual crabs frequently utilise habitats in small bays and inlets subject to episodes of hypoxic or low oxygen conditions, they are relatively poor osmoregulators and will move to shallow near-shore habitats or deeper water to avoid physiological stress associated with oxygen depletion (Chan et al. 2008, Curtis and McGaw 2008).

When Dungeness crabs reach sexual maturity at around two or three years of age (i.e., 100 mm CW), individuals migrate towards near-shore habitats to copulate (Rasmuson 2013). Mating between a recently moulted (soft-shell) female and an already moulted and hardened male generally occurs between April to September in the Strait of Georgia and Puget Sound (Rasmuson 2013). Although published data on timing of copulation is not available for B.C., observations of adults in amplexus (i.e., a part of the mating process in which a female is mounted by a male for a prolonged period) were frequent in late June and early July at Roberts Bank, and associated with the large Zostera marina bed in the low intertidal zone (Hemmera 2014a).

Highly fecund gravid females, each bearing about two million fertilised eggs, remain in subtidal habitat (Armstrong et al. 1988, Scheding et al. 2001) and form dense aggregations (i.e., up to 20 crabs/m2; Stone and O’Clair 2002) during the fall and winter (Jaffe et al. 1987, Dunham et al. 2011). Brooding habitats tend to be characterised by homogeneous coarse sandy substrate that is highly permeable and remains well-oxygenated (Scheding et al. 2001, Stone and O’Clair 2002). Tightly packed sediments (e.g., mud), may lead to fouling of egg clutches by limiting the rate of oxygen and metabolite exchange (Gray 1981, O’Clair et al. 1996). Optimal conditions under which eggs develop normally are suggested to be at a salinity of 25 psu and water temperature of 12 ºC (Mayer 1979). Brooding times range from 65 to 130 days, with the shortest durations corresponding to highest water temperatures (17 ºC) and lowest hatching success (Wild 1980). During this time, females must bury themselves into the sand 5 to 10 cm to maintain attachment of the eggs to their underside (or cephalothorax) (O’Clair et al. 1996). As a result,

Port Metro Vancouver Hemmera RBT2 – Marine Benthic Subtidal Study - 6 - August 2014 most brooding females are found partially or completely buried within the sediment, and their movement becomes relatively limited until the eggs are ready to hatch (i.e., between December and June in B.C.; O’Clair et al. 1996, Scheding et al. 2001, Rasmuson 2013). In addition, brooding female crabs typically do not eat during this time, and results from laboratory studies have shown females are able to survive up to six months without feeding (Schultz et al. 1996).

Gravid females have also been observed in deeper habitats (Stone and O’Clair 2002). Aggregating at greater depths may offer stability in temperature and salinity during the brooding season, particularly in estuarine ecosystems under strong riverine influence (Stone and O’Clair 2002). Females have been shown to return to the same brooding locations annually, where combinations of medium sediment-sized sandy substrates (with or without vegetative cover) and relatively shallow water depths form critical, and potentially limiting, habitats for this life history stage (Diamond and Hankin 1985; Armstrong et al. 1988; Scheding et al. 2001; Stone and O’Clair 2002). Consequently, habitats relating to sensitive brooding life history stage should be considered high management and mitigation priorities during anthropogenic development (Scheding et al. 2001).

2.2 FLATFISH SPECIES

2.2.1 Distribution

North Pacific flatfish as a group include over 35 species that are distributed along the western coast of North America, from the Bering Sea, Alaska to Baja, California (Kramer et al. 1995, McCain et al. 2005). Key species found along the coast of British Columbia include Pacific halibut (Hippoglossus stenolepis), English sole (Parophrys vetulus), Pacific sanddab (Citharichthys sordidus), speckled sanddab (Citharichthys stigmaeus), rock sole (Lepidopsetta bilineata), starry flounder (Platichthys stellatus), Dover sole (Microstomus pacificus), butter sole (Pleuronectes isolepis), sand sole (Psettichthys melanostictus), and flathead sole (Hippoglossoides elassodon). Flatfish are found across a wide range of depths, including the shallow intertidal and subtidal (e.g., English sole and rock sole) to depths of several hundred metres (e.g., Dover sole, flathead sole). Near-shore coastal habitats include bays, inlets, beaches, and estuarine ecosystems (Gibson 1994; Norcross et al. 1995; McCain et al. 2005). Most species also exhibit variation in depth distribution and habitat preferences related to seasonal activities, such as feeding or spawning, and different life history stages (McCain et al. 2005).

2.2.2 Habitat Requirements and Limiting Factors

Most Pacific flatfish species are entirely benthic, both as juveniles (0+ and 1+ age classes) and adults, and are closely associated with soft bottom substrates that range from fine silt and mud, to coarse sand and cobble sediment types (Moles and Norcross 1995, Norcross et al. 1995, Stoner et al. 2007). Several species, including rock sole and Pacific sanddab, are also common on hard bottom or mixed hard and soft bottom substrates (McCain et al. 2005). Previous studies have consistently documented the presence of Pacific flatfish species within the Roberts Bank study area (down to a maximum surveyed depth of −25 m CD) and the surrounding waters of the Fraser River estuary (Greer et al. 1980; Triton

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2004; Archipelago 2014a, 2014b). Initial studies in the 1970s (Greer et al. 1980) and results from subsequent trawl surveys in 2003 and 2004 (Triton 2004) indicate that flatfish species comprise the highest proportion of catches across all depths sampled within the intertidal and subtidal habitats at Roberts Bank. More recent trawl (Archipelago 2014b) and towed video surveys (Archipelago 2014a) have corroborated observations from previous studies, and reported that starry flounder, English sole, rock sole, sand sole, and Pacific sanddab are among the most abundant flatfish species within the Roberts Bank study area.

Generally, flatfish species display a life history in which juvenile stages utilise shallow nearshore habitats as nursery areas for at least the first month after metamorphosis (i.e., when both eyes travel onto one side of the head), even if initial settlement occurs on the open coast (Gunderson et al. 1990, Moles and Norcross 1995, Norcross et al. 1995, Gibson 1997). Some species, such as butter sole remain in offshore areas for the first year of life, and are less likely to utilise subtidal areas occupied by other flatfish species, such as English sole, reducing competition among juvenile life stages (Richardson et al. 2000). In contrast, juvenile starry flounder have been found within large coastal rivers and as far as 70 km upstream in the Fraser River, while adults have been shown to inhabit the lower, tidally-influenced reaches of the watershed (Richardson et al. 2000).

Recruitment by juvenile flatfish into nearshore subtidal habitats generally occurs by the summer (Hurst et al. 2007), which is congruent with site-specific results from Roberts Bank, where trawl surveys consistently showed higher abundance of juvenile flatfishes during the summer months, with decreasing numbers in the fall and winter. Further, the majority of flatfish species sampled at Roberts Bank in previous studies were in the juvenile life stage. These results suggest that Roberts Bank may provide important rearing habitat for flatfish (Triton 2004; Archipelago 2014a, 2014b).

Use of subtidal nursery areas by juvenile flatfish appears to be primarily related to depth and sediment size. Availability of fine-grain sediments such as mud and fine sand in intertidal and shallow subtidal habitats permits young flatfish to bury into the substrate making them less conspicuous to predators (Moles and Norcross 1995, Stoner and Ottmar 2003, Ryer et al. 2008). Predation has been documented as being the major cause of mortality of flatfish during the earliest life stages (Lemke and Ryer 2006). Demersal settlement at shallow depths may also be related to warmer ambient bottom temperatures that promote rapid growth of juvenile fish (Hurst and Abookire 2006), species-specific salinity preferences (Burke et al. 1991), and abundance of benthic prey, such as crustaceans, juvenile bivalves, infaunal worms, and small benthic fish (Gunderson et al. 1990, Gibson 1994, Rooper et al. 2003, Wouters and Cabral 2009). Structural complexity created by emergent vegetation or invertebrates, such as eelgrass (Pearson et al. 1992), tube-forming marine worms (Stoner et al. 2007), or sea pen beds (Archipelago 2014a) may also influence the recruitment, growth, and survival of juvenile flatfish (Rabaut et al. 2013). Recent studies suggest that structurally complex benthic habitats within estuarine ecosystems may serve

Port Metro Vancouver Hemmera RBT2 – Marine Benthic Subtidal Study - 8 - August 2014 as refuge habitats from predation and strong currents, and feeding grounds for juvenile fish, such as Pacific halibut and rock sole, by supporting high densities of potential prey (Stoner and Titgen 2003, Stoner et al. 2007, Pappal et al. 2012, Rabaut et al. 2013).

As juvenile fish grow and disperse from nursery grounds, they typically inhabit deeper offshore waters where they bury in coarser sediments (Moles and Norcross 1995, Gibson 1997). Seasonal migrations back to nearshore habitats to forage (e.g., rock sole, Dover sole) or to spawn (e.g., starry flounder, sand sole) in the summer is common for many north Pacific flatfish species (Gibson 1997, McCain et al. 2005). The majority of flatfish species spawn in the late winter and early spring, in offshore coastal areas (e.g., butter sole), shallow estuaries, or sheltered inshore bays (e.g., English sole, rock sole, sand sole) at variable depths of −5 to about −500 m; however, the exact timing and depth of spawning depends on the species and the geographical location (Hart 1973, McCain et al. 2005).

Most flatfish species broadcast spawn eggs and sperm into the water column, with fertilisation being external and the development of eggs occurring in the plankton (Gibson 1997). An exception is rock sole, which lays eggs that are adhesive and remain close to the bottom sediments (Gibson 1997). Pelagic larvae remain in the plankton, where they actively feed and undergo daily vertical migrations for a period of four weeks to several months depending on the species (Gibson 1997). Larval behaviour and their interaction with tidal currents and oceanic processes promote shoreward migration and recruitment into coastal or estuarine nursery habitats, where they settle on the bottom sediments and metamorphose into juveniles by late spring (Gunderson et al. 1990, Gibson 1997).

2.3 PACIFIC SAND LANCE

2.3.1 Distribution

Pacific sand lance is a small, short-lived schooling fish that is among the more abundant forage fish species in nearshore areas of the northeast Pacific (Therriault et al. 2009). PSL is of ecological importance throughout its range (Agler et al. 1999, Suryan et al. 2002, Hedd et al. 2006), which extends in the eastern North Pacific from California to the Beaufort Sea, and as far west as the Sea of Okhotsk (Russia) and Hokkaido (Japan) (Robards and Piatt 1999). Within the Salish Sea, PSL is heavily preyed upon by birds, fish, and marine and terrestrial mammals (Therriault et al. 2009) and is a key trophic link between plankton and upper trophic level species such as chinook salmon (Oncorhynchus tshawytscha) and the Endangered1 southern resident killer whale (Orcinus orca; SRKW) (Brodeur 1990, Ford and Ellis 2006). Distribution of PSL varies on multiple time scales, with alternations between benthic burying habitat and pelagic foraging habitat occurring both seasonally and diurnally. PSL are commonly found in water <−50 m deep, but can occur in waters down to −100 m (Lamb and Hanby 2005).

1 Status according the Species at Risk Act (2003)

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In B.C., seasonal schools of juvenile and adult PSL have been documented in shallow intertidal and subtidal habitats during spring and summer months along southwestern Vancouver Island (Haynes et al. 2007) including Barkley Sound (Haynes 2006, Haynes et al. 2008). Schools have also been observed in eelgrass habitats during the summer in other regions of B.C., including the Gulf Islands, Haida Gwaii, and Clayoquot Sound (Robinson and Yakimishyn 2013). Spawning has been documented in regions of southeast Vancouver Island (Thuringer 2004) and the lower mainland (CMN 2013), and extensively in Puget Sound and the San Juan Islands in Washington State (Penttila 1995, 2007).

At Roberts Bank, PSL have been caught in beach seine and trawl nets in numerous habitat types in the vicinity of Deltaport (Triton 2004, Archipelago 2014b, 2014c, 2014d). Forage fish beach spawn surveys along the west causeway did not locate PSL eggs; however, suitable habitat was identified based on published preference values (Archipelago 2014e).

2.3.2 Habitat Requirements and Limiting Factors

In the spring and summer along the western coast of North America, PSL has been observed in nearshore waters, alternating between schooling in pelagic waters and burrowing into intertidal or subtidal sand and fine gravel habitat (Haynes 2006; Haynes et al. 2007, 2008; Robinson and Yakimishyn 2013). Burrowing allows PSL avoid predation and conserve energy (Field 1988, Robards and Piatt 1999, Haynes et al. 2007). Evasion by burrowing has been observed by other sand eel species (Ammodytes spp.) in response to predators foraging near the seabed (Pinto et al. 1984). Lacking a swim bladder, it is also energetically costly for sand eels to remain in the water column when not foraging (Reay 1970). PSL will move from suitable sandy refuges to feed, with farther movements offshore (>5 km) during daylight foraging hours (van der Kooij et al. 2008). During the winter when zooplankton prey are scarce, PSL appears to remain in the substrate in a state of dormancy (Robards and Piatt 1999), leaving burying habitat between November and mid-February to spawn in the upper intertidal zone in beaches with sand or a mixture of sand and fine gravel (Penttila 2007, Thuringer 2004).

PSL and other sand eel species prefer seabed habitat for burying based on biophysical characteristics such as sediment grain size (Holland et al. 2005, Ostrand et al. 2005), sediment sorting (Haynes et al. 2008), depth (or elevation) (Ostrand et al. 2005), bottom current velocity (Greenstreet et al. 2010), and other characteristics such as shoreline type, distance to shore, and bottom slope (Ostrand et al. 2005). Re-use of patchy, suitable burying habitat by PSL can occur for extended periods in some locations, such as Barkley Sound off the west coast of Vancouver Island, where individual young-of-the-year (YOY; ≤ 90 mm fork length; Field 1988, Robards et al. 2002) have returned to the same patch for at least eight weeks (Haynes and Robinson 2011). Generally, coarse sand (approximately 0.25 to 2.0 mm) or sand-gravel substrates are preferred for burying by sand eel species (Reay 1970, Dick and Warner 1982, Holland et al. 2005, Ostrand et al. 2005, Haynes et al. 2007). In addition, the higher the silt content of the substrate, the less likely PSL are to bury within the sediment, as they require oxygenated sediment pore water to ventilate their gills (Wright et al. 2000, Holland et al. 2005).

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Within the subtidal zone, PSL are thought to prefer depths <−80 m CD and relatively high bottom current velocities (i.e., 25 to 63 cm/sec) (Robinson et al. 2013), possibly due to decreases in light intensity with increasing depth (Winslade 1974) and increased oxygenation of sediments with higher bottom current velocities (Robards et al. 1999). Pacific sand lance are visual foragers, and light intensity may act as a trigger for emergence from the sediment (Winslade 1974). In the North Sea and off Nova Scotia, PSL are associated with edges of shallow banks where surface sediment oxygenation is well-maintained by strong tidal currents (Macer 1966, Meyer et al. 1979).

Robinson et al. (2013) recently developed a habitat suitability model for PSL in the Strait of Georgia, identifying suitable burying habitat based on a combination of literature preference values and field sampling. Overall, the model identified 6% of the Strait of Georgia study domain as suitable burying habitat, with the southern Strait, including Roberts and Sturgeon banks, as being particularly important in encompassing the largest potential burying areas (Robinson et al. 2013).

Unique habitat constraints for PSL may exist for intertidal versus subtidal regions (Haynes et al. 2008). Specifically, Haynes et al. (2008) modeled intertidal habitat use by YOY PSL in Barkley Sound and hypothesised that PSL may have slightly different sediment requirements between intertidal and subtidal zones. Young-of-year PSL were found using sites with mean sediment size in the gravel range, whereas other studies indicated potential avoidance by PSL (Haynes et al. 2007) and a closely related sand eel species (Ammodytes marinus; Holland et al. 2005) of mean sizes within this range. Haynes et al. (2008) also found that YOY PSL avoided eelgrass in the intertidal zone, but not in the subtidal zone. Quinn (1999) found a significant inverse relationship between density of PSL and elevation in the intertidal, with higher densities below mean lower low water, and theorised that burying at lower elevations in the intertidal zone may reduce the risk of hypoxia and predation. Intertidal aggregations of PSL have been observed near stream or river mouths, and PSL has also been observed in brackish water, indicating a tolerance for low salinities (Dick and Warner 1982).

In recent surveys at Roberts Bank, YOY PSL were caught in the intertidal eelgrass bed north of the causeway in the spring and summer of 2012 and 2013 (Archipelago 2014c, d). Within the subtidal zone, nine PSL were caught in winter 2012 and 2013 in a single tow within the −5 to −10 m depth zone, the majority of which were also YOY (Archipelago 2014b). Purse seining captured PSL within deeper waters in the Inter-causeway Area, and at sites off the existing Roberts Bank terminals (Archipelago 2014c). While these observations confirm the presence of PSL in the nearshore intertidal and subtidal zones of Roberts Bank, presence in the water column is difficult to relate to the suitability of burying habitat within the intertidal or subtidal zones.

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2.4 VISUALSURVEYING APPROACHES

Underwater visual surveys are the most widely used method for rapidly assessing subtidal marine communities (Marliave and Challenger 2009, Assis et al. 2013, Bernard et al. 2013). In situ surveys by SCUBA divers are effective tools for estimating local species distribution, abundance, community diversity, and species-specific habitat use (Parravicini et al. 2010). Direct visual observations by divers also facilitate in-field taxonomic identification and gender classification of conspicuous species that cannot be readily identified by remote video imaging (Parravicini et al. 2010, Assis et al. 2013); however, sampling effort by divers is typically constrained by safe SCUBA dive regulations, such as limited bottom times and shallow dive depths of approximately −18 m (Parry et al. 2003, Parravicini et al. 2010). Moreover, observer-related biases can be large, since individual observers may differ in their ability to accurately estimate distances underwater, and locate or correctly identify rare or cryptic species immediately on-location (Bernard et al. 2013). Multiple diver sampling designs are a common approach used to increase the probability of detecting the range of species that may be present; however, environmental factors such as poor visibility, water temperature (i.e., exposure to cold water), the effect of ocean currents and waves, and habitat complexity can create challenging conditions that limit observational efficiency (Marliave and Challenger 2009, Bernard et al. 2013).

Small ROVs are becoming increasingly valuable tools used to study marine organisms and their habitats (Norcross and Müeter 1999, Johnson et al. 2003, Pacunski et al. 2013). ROVs can be used to conduct visual surveys and collect visual records of biological information on subtidal benthic communities, such as community composition, species associations, and local species richness (Pacunski et al. 2008, 2013). Deployment of underwater cameras mounted on ROVs also allows collection of qualitative to quantitative data on the presence, abundance, distribution, and densities of species, and evaluation of associated abiotic components such as sediment type, substrate cover, and habitat complexity (Norcross and Müeter 1999, Pacunski et al. 2013).

Small ROVs also offer several advantages for characterising biotic and abiotic components of subtidal habitats compared to alternative sampling methods, such as benthic trawls and nets. The utility of benthic trawling and other trapping methods is generally limited by the depth and complexity of bottom substrates (Adams et al. 1996, Norcross and Müeter 1999, Johnson et al. 2003). Small ROVs allow investigating and sampling of relatively complex or rugged ocean bottoms not accessible by trawls or nets, and can also be maneuvered to avoid potential hazards such as crab traps (Pacunski et al. 2008, 2013). Because bottom trawls sweep across seafloors, thereby integrating samples over relatively large areas, they provide limited information on species’ distributions and microhabitat use on smaller spatial scales (Norcross and Müeter 1999). Trawling and trapping methods are also restricted in the information they can collect on substrate type or topographic complexity, unless they are coupled with additional sampling methods such as sediment sampling (Stoner and Titgen 2003). Site-specific video observations through ROV surveying facilitate collection of more precise information on benthic fish and invertebrate microhabitat use or

Port Metro Vancouver Hemmera RBT2 – Marine Benthic Subtidal Study - 12 - August 2014 behavior and can be used to provide greater resolution of substrate preferences of target species (Stoner et al. 2007, Pacunski et al. 2008). Moreover, conducting surveys with ROVs allows non-destructive sampling in areas with potentially rare or fragile species, such as sea pens, which are sessile and highly sensitive to physical disturbance from bottom trawling (Parry et al. 2003, Hixon and Tissot 2007).

While SCUBA is a relatively low-cost method that can be employed in a variety of habitat types, the primary advantage of ROVs is that they are able to work at greater depths than are accessible by SCUBA divers, and for longer periods of time (Parry et al. 2002, Parravicini et al. 2010, Pacunski et al. 2013). ROVs are also able to estimate species diversity and other parameters across wider spatial scales, and are not limited by bottom time constraints (Norcross and Müeter 1999, Parry et al. 2002, Parravicini et al. 2010, Assis et al. 2013). A key limitation of ROVs is a general lack of manoeuverability in comparison with SCUBA divers, and thus decreased ability to detect species across highly-structured habitats where species may be concealed behind rocks or ledges (Marliave and Challenger 2009, Pacunski et al. 2013). Although the effects of water temperature and strong currents can be more easily overcome by ROV than by divers, poor visibility, turbulent underwater conditions, and limited field of view of video cameras may constrain the ability to detect species and estimate their abundance (Pacunski et al. 2013).

Towed underwater video systems (e.g., Seabed Imaging and Mapping Surveying technologies; SIMS) are also frequently used to identify benthic communities (Archipelago 2011, 2014a), and enable video collection at similar depths and speeds as ROV surveying; however, ROV methods allow greater control of in-field movement and observations than towed vehicles (e.g., in-field adjustments during video collection enable detection of subtle changes in bottom topography) (Parry et al. 2002, Pacunski et al. 2013). By manipulating the angle of observation, tilting mounted lights, or focusing the camera close to the sediment, ROV are able to gain more precise information about small cryptic fauna, habitat components such as sediment type, and sediment features associated with burrowing fauna (Norcross and Müeter 1999, Parry et al. 2002, Rooper et al. 2003).

Port Metro Vancouver Hemmera RBT2 – Marine Benthic Subtidal Study - 13 - August 2014

3.0 METHODS

Descriptions of the methods employed for the gravid female Dungeness crab survey and ROV survey are provided below. An overview is provided for each survey, as well as a description of the spatial and temporal scope, study methods, and data analysis.

3.1 GRAVID FEMALE DUNGENESS CRAB (SCUBA) SURVEY

3.1.1 Overview

The gravid female Dungeness crab survey seeks to improve the current state of knowledge on gravid female Dungeness crab density and habitat use within the shallow subtidal environment (≤−18 m CD) at Roberts Bank. The brood season for female Dungeness crab in the Strait of Georgia is presumed to occur from October to March (Dunham et al. 2011), during which females remain relatively inactive and are closely associated with subtidal substrate. SCUBA surveys were conducted to document the presence of gravid female crabs within the Roberts Bank study area during the winter brood season, and quantify their densities, depth distributions, and habitat preferences.

3.1.2 Study Area

The study area for the gravid female Dungeness crab survey encompassed the proposed RBT2 footprint area within the subtidal zone of Roberts Bank (Figure 1). Specific study areas included the terminal footprint itself and the adjacent caisson dredge and dredge basin areas, together referred to as the ‘dredge zone’ (DZ), which extends seaward (i.e., southwest) approximately 100 m from the RBT2 footprint (Figure 1). The maximum dive depth for this component of the Marine Benthic Subtidal Study was limited to −18 m in order to comply with Workers Compensation Board of B.C. safe dive regulations.

3.1.3 Temporal Scope

The temporal scope of the gravid female crab survey reflected the timing of the fall-winter brood season in the Strait of Georgia, and was intended to document current baseline conditions for gravid female crabs within the study area. Twelve SCUBA dives were conducted over a three day period from January 27th to 29th, 2013 by Archipelago Marine Research Ltd.

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Port Metro Vancouver Hemmera RBT2 – Marine Benthic Subtidal Study - 14 - August 2014

Figure 1 Marine Benthic Subtidal Study Area Offshore of the Roberts Bank Terminals

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Port Metro Vancouver Hemmera RBT2 – Marine Benthic Subtidal Study - 15 - August 2014

3.1.4 Study Methods

The SCUBA survey was completed using a random-stratified sampling design similar to that outlined in DFO’s ‘Manual for Crab Surveys in British Columbia’ (Dunham et al. 2011). The defined study area was divided into three depth zones or strata (0 to −5 m; −5 to −10 m; and −10 to −20 m), which were further stratified into four geographic locations along the delta-front slope to enable even distribution of transects and sampling effort (Figure 2). Three transect start points (one per depth zone) were randomly chosen within each geographic location, and twelve 100 m transects were plotted roughly parallel to depth contours (Figure 2).

The boat operator located the predetermined start point locations of each transect using GPS and deployed an anchor buoy. At the surface, the following data were recorded:

 Date, start and end time, and GPS coordinates of transect start point;

 Transect number;

 Field measurements of temperature, salinity and dissolved oxygen (DO); and

 Tidal state (ebb, flood, slack).

A weighted YSI Inc. probe was lowered from the vessel and suspended approximately 30 cm off the sea floor at each transect start or end point, and water temperature, salinity, and dissolved oxygen (DO) measurements were recorded.

Transects were surveyed by a team of two divers. Diver One followed a pre-determined bearing using a compass and depth gauge, and gradually unwound a spool line, while Diver Two recorded the presence of all crabs within a 2 m boundary either side of each transect (e.g., 4 x 100 m or 400 m2 corridor). Due to high currents at some deeper transect locations, and associated health and safety concerns, divers set transect lines in the direction of the current, instead of against it.

All crabs visible to the divers were pursued and captured, and the following characteristics were recorded:

 Sex;

 Location along transect;

 Carapace width (mm) for females; and

 Buried or not buried.

Port Metro Vancouver Hemmera RBT2 – Marine Benthic Subtidal Study - 16 - August 2014

General habitat features were characterised for each transect location and recorded at the end of each survey. Water depth (m) was recorded using a depth gauge. Due to time constraints, underwater visibility (m) was measured using transect tape in Transect 7 and estimated based on diver perception for all other transects. Slope was determined by estimating slope rise perpendicular to the transect line over a 4 m length, such that slope was classified as ‘flat’ when there was <0.6 m difference in depth, and classified as ’low’ when the depth difference ranged from 0.6 to 2.1 m. Substrate features including bioturbation and ripple percent cover were estimated across the length of each transect. The number of crab traps and orange sea pens (Ptilosarcus gurneyi) encountered were also recorded.

To record additional biophysical parameters, ten 0.5 x 0.5 m quadrats were placed at pre-determined locations, at every 10 m along each transect line. For each quadrat, the following information was recorded:

 Substrate type: mud, clay, sand, shell hash, shell whole, woody debris (% cover);

 Bioturbation and ripple (% cover);

 Macroalgae: drift algae1, clumped algae1, algal detritus (% cover);

 Sea pens (number); and

 Other fish/ invertebrates encountered (number).

3.1.5 Data Analysis

Very few gravid crabs were observed; therefore, statistical tests could not be conducted.

1 “Drift algae” refers to algae that are in full form, laying on top of, but not attached to, a substrate. “Clumped algae” refers to shredded algae that have been compacted into a clump or mat on top of the substrate.

Port Metro Vancouver Hemmera RBT2 – Marine Benthic Subtidal Study - 17 - August 2014

Figure 2 SCUBA Dive Transect Locations for the Gravid Female Dungeness Crab Survey

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Port Metro Vancouver Hemmera RBT2 – Marine Benthic Subtidal Study - 18 - August 2014

3.2 REMOTELY-OPERATED VEHICLE (ROV) SURVEY

3.2.1 Overview

A ROV survey was conducted with the objective of collecting invertebrate and fish density and habitat use data across all depths and habitats encompassed within the subtidal zone at Roberts Bank. For each transect, benthic invertebrates and fish were identified (where possible) and enumerated, and densities were determined. Habitat variables were also determined along intervals of each transect to assess whether densities of organisms within the subtidal environment differed based on habitat characteristics. Sediment collection was carried out during this survey in conjunction with previous sediment sampling efforts to cross-validate observational data on substrate type. Differences in species’ (or species complex) densities among depth zones and habitats were quantitatively assessed using statistical analyses.

3.2.2 Study Area

The study area for the ROV survey and associated collection of sediment samples was the subtidal zone of Roberts Bank, specifically the deeper waters of the proposed terminal footprint, the adjacent DZ, and subtidal habitat immediately offshore from the DZ, to a maximum depth of −40 m (Figure 3). The maximum depth of this survey extends by approximately double the maximum depth of the DZ, allowing a comparison of subtidal species’ densities inside and outside of the proposed DZ.

3.2.3 Temporal Scope

Benthic invertebrate and fish species at Roberts Bank, specifically Dungeness crabs, PSL, and dominant flatfish species, are expected to exhibit seasonal variation in subtidal depth distribution and habitat use related to timing of key life history stages. Timing of the ROV survey was intended to capture the existing conditions within the study area during the summer season and to supplement data collected during the winter SCUBA survey and previous studies on benthic fish abundance at Roberts Bank (Triton 2004, Archipelago 2009, 2014b). The ROV transect and associated sediment sampling within the study area was conducted during daylight hours over a three day period from July 23 to July 25, 2013.

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Figure 3 Remotely-Operated Vehicle Survey Transect Locations

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Port Metro Vancouver Hemmera RBT2 – Marine Benthic Subtidal Study - 20 - August 2014

3.2.4 Study Methods

3.2.4.1 ROV Transect Survey

The ROV survey transects were generated using a random-stratified sampling design based on four depth zones within the study area: −5 to −10 m, −10 to −20 m, −20 to −30 m, and −30 to −40 m (Figure 3). Each depth zone was additionally stratified into three geographic locations along the delta-front slope to distribute sampling effort evenly throughout the study area. In total, 12 strata (i.e., four depth zones x three locations) were generated for sampling. Random points were then generated (one per stratum) to serve as start locations for each transect, for a total of 12 planned transects. Twelve back-up transect locations were also generated for each zone to account for possible complications, such as the presence of obstructing crab gear along planned transects. Transects were plotted roughly parallel to depth contours, and end points were generated based on a transect length of 400 m (Figure 3).

The ROV survey was conducted using a 34 foot research vessel, the MV ‘Crown Royal’, owned and operated by Ocean Dynamics. The field crew consisted of a boat driver and an ROV pilot, both experienced biologists, and a deck hand to aid in deployment and retrieval of the ROV. Hemmera biologists were on-board to act as additional video reviewers.

A Seaeye© Falcon 12127 ROV model was used, rated to a depth of −300 m (Appendix A: Figure A-1; Appendix C: Photo C-1). The ROV was deployed and retrieved using a hydraulic marine winch system, and remained attached to the support vessel via a 450 m (max) umbilical during surveying (Appendix C: Photo C-2 and C-3). The ROV umbilical was tethered to the winch cable during deployment using duct tape and, an 11.3 kg clump weight, used to absorb current drag, was fixed to the umbilical at the location where the ROV was first tethered, approximately 30 m from the ROV.

Video was recorded using two professional underwater cameras: a high resolution fixed wide angle camera (Seaeye© Colour Camera CAM04N) and a compact colour zoom camera (Kongsberg© OE14-115) with 10:1 zoom capabilities mounted on a 180° tilt platform. Video was relayed in real-time to the support vessel along with date, time (hours: minutes: seconds), compass heading (mag), depth (m), camera tilt angle (degrees), and turn counter. Five LED lights (total 10,000 lumens) mounted on the ROV were used to illuminate the field of view, and scaling lasers set 0.2 m apart were used to ensure that field of view remained as constant as possible during piloting. Complete video files were obtained from Ocean Dynamics upon completion of the ROV Survey and stored as back-ups on the Hemmera file server. Post-field video review was carried out by Ocean Dynamics, and is described in Section 3.2.5.

Underwater positioning of the ROV was monitored using an ORE Trackpoint II Ultra Short Baseline (USBL) navigation system, consisting of an acoustic transducer attached to a pole that reached over the side of the boat, and a transponder attached to the ROV to give the relative position of the ROV as x, y coordinates. Differential Global Positioning System (DGPS) locations were obtained using a Trimble

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TSC1 Asset Surveyor, and ship heading and gyro1 were recorded using a TCM2 3-Axis Compass Module. During piloting, DGPS, TCM2, ROV telemetry (i.e., depth, heading, pitch and roll), and sensor position offsets fed into ‘Workboat’, which is an onboard navigation software by Seanav (www.seanav.com). ROV depth was fed from Workboat back into Trackpoint II to be used as a given depth, and to assist with the relative position solution. Workboat displayed the vessel to scale and ROV position in real time every second. A velocity filter in Workboat was set to 2 m per second (m/sec) and used in real time to help the ROV pilot and vessel skipper maintain ROV location. Raw, unfiltered data including ROV position solution, ROV depth, and heading, were logged every second (Appendix A: Figure A-2). The ROV transect lines for plotting in ArcGIS were created in Workboat using a basic plot interval and then imported into Ozi Explorer DGPS Mapping software. Obvious outliers were filtered out manually by Ocean Dynamics biologists. Appendix A: Figure A-2 shows an example of a filtered transect line, labeled by transect number.

Efforts were made to run all ROV transects at an average speed of 0.2 m/sec. The literature reports ROV speeds between 0.25 and 0.75 m/sec as optimal for identifying larger (>10 cm) benthic fishes, such as lingcod and rockfish (Pacunski et al. 2008). At speeds >0.75 m/s, cryptic fishes are difficult to image or identify, and slower ROV speeds result in longer transect and video processing times, without resulting in greater numbers of fish encountered (Pacunski et al. 2008). Prior to surveying, it was estimated that an average speed of 0.2 m/sec would allow a transect distance of 400 m to be covered in approximately 2,000 sec (or 30 to 35 minutes) and that the total planned distance of 4,800 m should be completed in approximately seven hours of bottom time.

Efforts were also made to survey either during ebb or slack tide, when tidal currents are less severe in the study area. The pilot maintained a constant linear heading where possible; however, extreme currents were occasionally encountered that severely hampered the ability of the pilot to maintain course, and resulted in events were the camera was stopped or was ‘off-bottom’ (i.e., scaling lasers were not visible on the substrate). Repeat transects were run for what were considered to be the most compromised transects (e.g., Transect 16 and Transect 21; Figure 3) using a heavier clump weight (136.0 kg) affixed to the winch wire, and still allowing the ROV 30 m of flying tether (Appendix A: Figure A-1). The extra weight dramatically limited sideways and vertical motion of the ROV.

On-bottom obstructions were minimal, as Roberts Bank is a low gradient, low complexity habitat; however, obstructions such as derelict fishing gear (e.g., crab traps and line) were occasionally encountered. In these instances, slight deviations from the track line were necessary, and were taken into account during video review. Sessile organisms, such as sea pens, were also encountered throughout the survey. Sea pens can pose ‘biological hazards’ to an ROV, capable of fouling thrusters and

1 A measurement of stability provided by a gyroscope that allows maintenance of a reference direction.

Port Metro Vancouver Hemmera RBT2 – Marine Benthic Subtidal Study - 22 - August 2014 preventing the shaft from turning (Pacunski et al. 2008). When sea pens were encountered, the height of the ROV above the bottom was slightly increased. The effects of these in-field adjustments were quantitatively assessed during path width and area calculations post survey, as discussed further in Section 3.2.5.1 below.

Recorded video was used to make post-field observations to obtain the following general and biological data along each transect (please refer to Section 3.2.5.1 for more detail on how each parameter was calculated):

 Interval length (IL) (m);

 Interval width (IW) (m);

 Transect length (TL) (m);

 Mean transect width (TW) (m);  Number of crabs (identified to species level where possible);

 Number of Dungeness crabs (total, buried and non-buried);

 Dungeness crab size (carapace width; mm) for each crab encountered (where measurement was possible);

 Number of finfish (identified to species level where possible);

 Number of flatfish (total, buried and non-buried);

 Flatfish size (total length, TL; mm) for each flatfish encountered (where measurement was possible);

 Number of PSL;

 PSL size (total length, TL) (mm) for each PSL encountered (where possible);

 Number of sea pens; and

 DGPS locations for observed Dungeness crabs and flatfish.

Physical habitat data, including substrate class, substrate cover, and complexity percent cover were also qualitatively characterised from the recorded video (see Appendix B: Table B-1). Incidental observations, such as the presence and absence of algae, derelict gear, and other non-target invertebrates were also made during video review.

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3.2.4.2 Sediment Sampling

Sediment sampling was conducted at selected locations as part of the ROV survey with the objective to quantify grain size and correlate it with species presence (Figure 4). Sampling was carried out over the course of two half days (July 24 and 25) at the start and end points of all transect locations using a Van Veen© grab. The grab was deployed and retrieved using a hydraulic marine winch system. Photos were taken of each sediment grab (Appendix C: Photos C-14 and C-15). Post sampling analyses of grain size were carried out at ALS Laboratories (Vancouver, B.C.). For further details regarding sediment sampling methods and lab analyses, refer to the Hemmera Sediment and Water Quality Characterisation Studies Technical Data Report (Hemmera 2014b).

Grain size results from multiple surveys were combined and used to characterise the substrate within the subtidal environment at Roberts Bank and correlate it with faunal characteristics (e.g., crab, flatfish, and sea pen densities). Methods used for determining mean grain size from laboratory results and for mapping mean grain size are described in detail in Section 3.2.5.2. To verify the accuracy of each method, substrate classes obtained through surface interpolation were compared with those qualitatively estimated during video review.

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Figure 4 Van Veen© Sediment Sample Locations from the Remotely-Operated Vehicle Survey

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3.2.5 Data Analysis

3.2.5.1 ROV Video Analyses

The ROV video files were reviewed by an experienced biologist using Ulead© video analysis software. Video files for each transect were initially reviewed to determine video interval time (t, sec.), such that approximately 10 m of bottom were reviewed for every video interval. Video interval time was determined for each transect using calculations (described below) that took into account both ‘stoppage’ and ‘off bottom’ events (refer to Appendix B: Table B-2). These calculations were necessary due to the difficult field conditions encountered, which resulted in anomalous events during all transect runs. ‘Stoppage’ events were those where forward progress of the ROV was halted for one of the following reasons:

1. due to challenging bottom currents or other environmental factors; 2. to adjust boat location relative to the ROV due to changes in environmental conditions (e.g., current, wind, swell); 3. to make adjustments to the ROV (e.g., thruster wash); or 4. to zoom in on a particular organism for better identification.

‘Off bottom’ events were those where all of the following criteria were met:

1. The ROV was not stopped but instead covered ground along the transect; 2. Bottom was not clearly visible due to a combination of vertical distance of the ROV off the bottom and limited water column visibility;

3. ROV lasers were not visible on bottom due to limited visibility; and 4. No abundance information (by species) was collected due limited visibility.

Periods where the ROV lasers were obscured, but where vertical distance off bottom (and hence field of view) could be extrapolated from similar adjacent frame(s), were included in the analyses.

For each transect, total stoppage time (sec) was determined by summing times for individual stoppage events, and then subtracting this time from the total transect time (Tt) (sec) to obtain a new total transect time minus stoppages (Tt-stop) (sec) for calculation of interval time (t). Interval time was determined using total transect length (TD-DGPS) (m) (i.e., total linear distance travelled, based on GPS shape files) and Tt- stop. Specifically, the number of seconds it took to cover 10 m was determined for each transect, assuming a relatively constant ROV speed during forward movement along the entire transect length.

Where ‘off bottom’ events occurred, these periods were included in calculations of transect speed and interval time, as forward movement was still occurring, with the exception of analyses of species density or habitats because transect width was not calculable. For each transect, total off bottom time (sec) was determined by summing times for individual off bottom events. Total distance off bottom (m) was

Port Metro Vancouver Hemmera RBT2 – Marine Benthic Subtidal Study - 26 - August 2014 determined by dividing the number of seconds it took to cover 1 m by the total off bottom time (sec), and then subtracting this time from total transect length for a new total distance on bottom, or corrected transect length (TL) (m).

With interval time varying slightly among transects, intervals of approximately 10 m were video reviewed for species’ and qualitative habitat class data. Where stoppage event(s) occurred during 10 m intervals, video review time based on the duration of each stoppage was added to the end of each segment to ensure approximately 10 m of bottom was reviewed per interval. Similarly, where off bottom events occurred during 10 m intervals, video review time was added to the end of the interval for a full 10 m of useable data for which species’ densities could be calculated. Intervals at the end of each transect were often less than 10 m. In these cases, interval time was used to calculate approximate interval distance as well as interval area.

2 Area for each interval (IA, m ) was calculated by taking the product of the distance on bottom (or interval distance, i.e., 10 m, with the exception of the last interval; IL) and the interval width (IW). Width was first estimated for each interval by measuring the distance between lasers on the monitor screen (L) at the start, middle, and end of every segment, and using average laser width (Lavg) in the following equation:

IW = (M*0.2)/Lavg (Equation 1)

Where M = width of the view of the monitor (m);

Lavg = distance between the lasers on the monitor screen every 30 seconds (m); and

0.2 = actual width (m) of the lasers reflected on the substrate.

2 Transect area (or swept area) (TA, m ) was calculated by taking the product of the total distance on bottom (or transect length; TL) and the mean transect width (TW). TW was estimated by summing all interval widths (IW) and dividing by the total number of intervals per transect.

Densities of Dungeness crab (total, buried, non-buried, and by size category), finfish (total), flatfish (total, buried, non-buried), and sea pens were calculated using organism counts per interval and per transect, and calculated interval and transect areas.

Approximate GPS locations for each Dungeness crab and flatfish encountered were determined by noting the time stamp at which each organism was encountered and comparing this time stamp with GPS locations from the raw, unfiltered data files provided by Ocean Dynamics. If the time stamp at which an organism was observed fell along the filtered transect line, it was deemed acceptable. Alternately, if the time stamp corresponded to a location that was an outlier, the closest location along the filtered transect line was chosen as representative.

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Invertebrates

All crabs (Dungeness and non-target species) were identified to the lowest taxa possible, usually species, and enumerated for each 10 m video interval along each transect. Efforts were made to identify Dungeness crabs buried in the sediment, as either: 1) a depression left in the substrate for respiration; and/or 2) a visible rostrum and/or antennae. This technique of identifying buried crabs using ROV has been verified in previous studies (Parry et al. 2003, MacKenzie 2010).

Dungeness crab size (i.e., CW in mm) was calculated where possible using the following equation:

CW = (CWscreen*200)/L (Equation 2)

Where CWscreen = carapace width of the crab on screen;

L = distance between the lasers on the monitor screen; and

200 = distance (mm) between laser points on the substrate.

Where the aspect of the crab in relation to the ROV camera did not allow measurement, or the crab was buried in the substrate, the crab was assigned a ‘NM’, or not measurable, code.

Sea pens were enumerated for each 10 m video interval along each transect, and total counts along transects were determined. Incidental observations of other invertebrates, such as anemones and sea stars, were recorded per transect interval, but were sparse in comparison to Dungeness crabs and sea pens and were therefore not included in subsequent density calculations.

Benthic Fish

As with crabs, all finfish (flatfish and forage fish) were identified to the lowest taxa possible, and enumerated for each 10 m video interval along each transect. Finfish were only counted if they originated from between the ROV skids (i.e., field of view), not if they entered from outside of the skids. Identification to species level was difficult in most instances due to poor visibility, an inability to see distinguishing features due to the aspect of the fish relative to the camera, and the relatively quick flight responses of finfish, especially flatfish, from the field of view of the ROV camera.

Where possible, flatfish size (i.e., total length, TL) was calculated using the following equation:

TL = (TLscreen*200)/L (Equation 3)

Where TLscreen = total length of the flatfish on the screen (mm);

L = distance between the lasers on the monitor screen; and

200 = distance (mm) between laser points on the substrate.

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Sizes of flatfish were only estimated from video footage if the body of the fish was oriented perpendicular to the axis of the camera (Norcross and Müeter 1999).

3.2.5.2 Sediment Analyses

To characterise substrate within the study area, including locations where grab samples were not collected, surface interpolation was used to create a continuous (or predicted) surface of sediment grain size. First, a geometric approach was used for calculating mean sediment grain size for each grab sample. Specifically, geometric mean grain size was determined from percentile values obtained from linear interpolation between log-transformed mm sizes (Bunte and Abt 2001). The nth root geometric approach was used to compute mean grain size, based on the percentiles at the point of curvature (Bunte and Abt 2001):

Mean sediment grain size (mm) = √퐷16 + 퐷84 (Equation 4)

where ‘D’ represents grain size, in mm; and subscripts ‘16’ and ‘84’ represent 16% and 84%, respectively.

A geometric mean sediment grain size approach was used, rather than a categorical method based on percentiles, given that sediment grain size preference results for PSL presented in the literature are for mean grain size (Robinson et al. 2013). An analysis of faunal densities, including PSL density, in relation to sediment grain size, was an objective of this study.

A classified seabed mean sediment grain size map was then created using inverse distance weighted (IDW) interpolation. A uniform grid size of 20 m was applied, along with a variable search radius of 500 m and a maximum of 12 sample points. For more details on IDW calculations and limitations, refer to Appendix D: Supplementary Information.

Initially, a seabed map was created using a relatively coarse Wentworth grain size classification (Wentworth 1922):

 Gravel >2.0 mm;  Sand 0.063 mm to 2.0 mm;  Silt 4.0 μm to 0.063 mm; and  Clay <4.0 μm.

The resulting IDW map (Appendix A: Figure A-3) indicated that the predominant mean grain size throughout the study area corresponded to the coarse class ‘sand’, with little substrate differentiation. While this coarse classification verified qualitative substrate class assessments noted during video review (i.e., almost all intervals classified as ‘sand’), it precluded a thorough analysis of faunal densities relative

Port Metro Vancouver Hemmera RBT2 – Marine Benthic Subtidal Study - 29 - August 2014 to grain size. To assess whether relationships existed between faunal densities and mean sediment grain size, a second map was created using a finer scale Wentworth class resolution breaking down sand into multiple classes (based partly on PSL grain size preferences):

 Coarse sand 0.25 to 2.0 mm;  Fine sand 0.125 to 0.25 mm;  Very fine sand 0.0625 to 0.125 mm; and  Silt <0.0625 mm.

This IDW map, presented as Figure 5, reveals multiple sediment classes within the study area and was thus used in subsequent analyses.

To explore the relationship between faunal densities and surface-interpolated mean sediment grain size, there was a need to map interval start and end points along each filtered transect line. Raw ROV position locations were available for every second of ROV travel (as discussed in Section 3.2.4); however, these raw locations could not be used to determine interval start and end points given the relatively high frequency of outliers (e.g., when compared with raw ROV position locations, time stamps for interval start or end points occasionally corresponded to outlier locations; Appendix A: Figure A-2).

To map intervals along filtered transect lines and over IDWs of mean sediment grain size, for each interval, the total ‘stoppage time’ per interval (Istop) (sec) was subtracted from the total interval time (It)

(sec) for a new interval time minus stoppages (It-stop) (sec):

It-stop = It - Istop

‘Off bottom’ times were left in the calculations of approximate interval distances, given that the ROV was moving forward during off bottom events. Approximate distance travelled by the ROV for each interval (ID)

(m) was calculated by multiplying the It-stop by average transect speed (m/sec), with most intervals being approximately 10 m in linear length. Exceptions were intervals containing off bottom events (resulting in greater distances travelled), and the final interval of each transect, which was always less than 10 m.

Average transect speed was based on the total transect length (TD-DGPS) (m) (total linear distance travelled, based on DGPS shape files), and total transect time minus stoppages (Tt-stop):

ID = It-stop*(TD-DGPS/Tt-stop)

To determine approximate start and end points of each interval along each filtered transect line, a ratio interval distance (IDr) was determined for each interval by multiplying ID by the length of the filtered transect line (TD-filtered) (m) and dividing by the total transect length (TD-DGPS):

IDr = (ID*TD-filtered)/TDGPS

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The dominant sediment grain size within each interval was then determined based on the IDW raster grid used to map geometric mean sediment grain size (Figure 5). Where an interval length crossed more than one raster, the interval distance (m) falling within each raster was determined (IDr). The dominant geometric mean sediment grain size within each interval was defined as the geometric mean sediment grain size corresponding to the greatest IDr. The finer Wentworth scale (Wentworth 1922) was then used to classify each dominant geometric mean sediment grain size value per interval into a corresponding sediment class (Figure 5).

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Figure 5 Remotely-Operated Vehicle Transect Lines Overlying Fine Resolution Inverse Distance Weighted (IDW) Interpolation of Geometric Mean Sediment Grain Size (mm) within the Study Area

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3.2.5.3 Statistical Analyses: Habitat Associations

Effects of sediment grain size and depth on the density of the different species treatments (Table 2) were tested using separate two-factor analysis of variance (ANOVAs) on density by interval, while significant effects of depth and sediment grain size were explored using Tukey’s honest significant difference (HSD). Next, a separate one-way ANOVA was used to determine if the density of each species treatment differed among geographical locations: 1) along the delta-front slope; and 2) inside and outside the proposed terminal footprint and DZ. Significant effects of geographical location were also explored using Tukey’s HSD.

Individual linear regressions were run to test whether a relationship exists between orange sea pen density and each species treatment (Table 2). The assumption of normality was tested using a Shapiro- Wilk test. Data were square-root (SQRT) transformed to conform to the assumptions of ANOVA. Data analyses were performed in JMP (SAS) v. 4.0.4.

Table 2 Species Treatment Response Variables Measured During the ROV Survey

Species Treatment Number Species Treatments 1 Total Dungeness crab density 2 Dungeness crab density, buried 3 Dungeness crab density, non-buried 4 Total crab density (all species) 5 Orange sea pen density 6 Total flatfish density 7 Flatfish density, buried 8 Flatfish density, non-buried 9 Total finfish density (all species)

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4.0 RESULTS

This section presents the main findings of the Marine Benthic Subtidal Study for the gravid female Dungeness crab survey and the ROV survey.

4.1 GRAVID FEMALE DUNGENESS CRAB SURVEY

4.1.1 Study Results

Transect depths ranged from −1.70 m CD to a maximum of −14.2 m CD (Appendix B: Table B-3). Estimated underwater visibility was relatively poor and varied from 3 to 13 m (Appendix B: Table B-3). Among all transect sites, temperature ranged from 7.2 ºC to 7.8 ºC, salinity ranged from 26.0 psu to 29.9 psu, and DO concentrations varied from 7.4 mg/L to 9.6 mg/L (Appendix B: Table B-4).

Survey transects were conducted by SCUBA divers over a predominantly sandy substrate, averaging 85 to 100% sand based on qualitative assessments of substrate (Appendix B: Table B-5). No attached macroalgae were present at any of the transect locations; however, drift algae, clumped algae, and algal detritus were observed either as a layer on top of the substrate or covered by a fine layer of sand (Appendix B: Table B-5). Mud was present in four out of the 12 transects surveyed, and to a lesser extent, a ‘clay-like’ fine sediment was observed at Transects 7 and 10.

4.1.1.1 Crab Observations

A total of 38 Dungeness crabs were encountered at 9 of the 12 transect sites. 61% (n=23) were males, and 11% (n=4) and 3% (n=1) were gravid and non-gravid females, respectively (Table 3), while 10 crabs could not be sexed as they quickly scattered away from the divers avoiding capture. All identified female crabs were found buried in the sediment, while the majority of male crabs (74%) were not buried (Table 3). Gravid female crab CW varied from 110 to 131 mm (Table 3).

The majority of Dungeness crabs were observed within the deeper depth zones, with 24% (n=9) and 76% (n=29) of crabs occurring in the −5 to −10 m and −10 to −20 m depth strata, respectively. No crabs were observed within the 0 to −5 m depth strata (Table 3). The mean number of crabs was significantly higher in the −10 to −20 m depth stratum than the 0 to −5 m (p = 0.002) and the −5 to −10 m (p = 0.04) strata, while the 0 to −5 m and −5 to −10 m strata were not significantly different from each other (p = 0.8; Figure 6).

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Only four gravid female Dungeness crabs were encountered (n=4), and these were located along 3 of the 12 surveyed transects (Figure 2 and Table 3). Mean gravid female crab density was 0.0008 crabs/m2 across all transects. The few gravid crabs observed were most abundant (75%, n=3) in the deepest depth zone surveyed (−10 to −20 m), corresponding to a mean density of 0.002 crabs/m2 (Figure 7).

Table 3 Dungeness Crabs Identified During the Gravid Female Dungeness Crab (SCUBA) Survey

Female Male Depth Carapace Width (CW) Transect Unknown Strata (m) (mm) Buried NB1 Buried NB1 Gravid Non-gravid 1 0 to −5 - - 0 0 0 0 0 2 0 to −5 - - 0 0 0 0 0 3 0 to −5 - - 0 0 0 0 0 4 0 to −5 - - 0 0 0 0 0 5 −5 to −10 - - 0 0 0 0 0 6 −5 to −10 - - 0 0 0 1 0 7 −5 to −10 - - 0 0 1 3 1 8 −5 to −10 111 - 1 0 0 2 0 9 −10 to −20 - - 0 0 0 6 4 10 −10 to −20 - 110 1 0 1 0 4 11 −10 to −20 131, 127 - 2 0 1 5 1 12 −10 to −20 126 - 1 0 3 0 0 5 0 6 17 Total 5 23 10

1 Non-Buried

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Figure 6 Comparison of Mean Numbers of Dungeness Crabs among Depth Strata

Note: Error bars indicate 95% confidence intervals. Open circles denote data outside of the 95% confidence intervals.

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Figure 7 Comparison of Mean Numbers of Gravid Female Dungeness Crabs among Depth Strata

Note: Error bars indicate 95% confidence intervals.

4.1.1.2 Non-target Invertebrates

Divers identified other invertebrate and fish species within the study area, including non-target crab species, two species of nudibranchs, plumose anemones (Metridium farcimen), starry flounder, and two species of sea stars (refer to Appendix B: Table B-3); however, species distributions were variable among transects that spanned different combinations of depth strata (Appendix B: Table B-3). Orange sea pens were the most abundant invertebrate species and were widely distributed across all of the

Port Metro Vancouver Hemmera RBT2 – Marine Benthic Subtidal Study - 37 - August 2014 transect sites, with counts ranging from 1 to 200 sea pens/transect (Appendix B: Table B-3). Incidental observations included a longnose skate (Raja rhina) along Transect 8 and a big skate (Raja binoculata) egg case along Transect 10 (Appendix B: Table B-3).

4.2 REMOTELY-OPERATED VEHICLE (ROV) SURVEY

4.2.1 Study Results

All transects were conducted on an ebb tide with the exception of Transect 22, which was started on an ebb and completed during a flood tide (Appendix B: Table B-6). ROV interval depth varied from 8.3 to 41.3 m (Appendix B: Table B-6). ROV speed was relatively constant along all transects (0.2 +/- 0.02 m/s), with a minimum speed of 0.16 m/sec and a maximum of 0.24 m/sec (Appendix B: Table B-6).

After correcting transect length (TL) for ‘off bottom’ events (Appendix B: Table B-2), TL ranged from 382 to 417 m, with an average TL of 401 m (Appendix B: Table B-7). Average transect width (TW) surveyed by the ROV varied between transects from 0.50 to 0.84 m, with an overall average TW of 0.67 m 2 (Appendix B: Table B-7). Total transect area surveyed (TA) was 3,251.6 m (Appendix B: Table B-7).

4.2.1.1 ROV Video Analyses

Invertebrates

Dungeness Crabs

Dungeness crabs (Appendix C: Photo C-4) were found along all 12 transect sites and were the most abundant crab species observed, and second in overall faunal abundance only to orange sea pens, with a total of 102 observations (Appendix B: Table B-8). GPS locations for Dungeness crabs are plotted in Appendix A: Figure A-4. On average, nine Dungeness crabs were found per transect, with an average density of 0.03 crabs/m2 within the total transect area surveyed (Appendix B: Table B-8). Visual identification of buried crabs was obstructed by poor visibility. Generally, buried crabs were only visible when disturbed from the sediment by the ROV (Appendix C: Photo C-5). A total of 22 buried Dungeness crabs (21.5% of total crab observations) were found, with an average density of 0.007 buried Dungeness crabs/m2 (Appendix B: Table B-8). Dungeness crab carapace size calculations were possible for 14 individuals (Appendix B: Table B-9); however, statistical analyses based on size groupings could not be carried out due to low samples sizes.

Orange Sea Pens

Orange sea pens (Appendix C: Photos C-6 and C-7) were widely distributed across 11 out of 12 transect sites and were the most abundant invertebrate species (and overall group of organisms) identified during the ROV survey (n=1,258) (Appendix B: Table B-10). Sea pen distribution was highly variable across transect locations, ranging from zero to 536 sea pens per transect, with an average density of 0.38/m2 among transect locations (Appendix B: Table B-10).

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Other

The ROV video analyses identified at least four non-target crab species across all transects and depth zones: graceful decorator crab (Oregonia gracilis; n=18), tanner crab (Chionoecetes bairdi; n=6), red rock crab (Cancer productus; n=3), and northern kelp crab (Pugettia productus; n=1). Five additional crab observations were made that could not be identified to species (Appendix B: Table B-11). An average of three non-target crabs were observed per transect, with an average density of 0.01 crabs/m2 across transects (Appendix B: Table B-8).

Incidental observations of non-target invertebrates included an anemone species in Transect 17 (order Actiniaria, n=1) (Appendix C: Photo C-8), and sea star species (class Asteroidea, n=4), including sunflower sea stars (Pycnopodia helianthoides, n=3), and an unidentified sea star species in Transect 22 (n= 1) (Appendix B: Table B-11). Other incidental observations along transect sites included five crab traps (Appendix B: Table B-10). Algae were present in all of the transect locations surveyed, with the percentage of intervals within each transect that contained algae ranging from 14 to 100% (Appendix B: Table B-10).

Benthic Finfish

Flatfish

Flatfishes (n= 422) (Appendix C: Photos C-9 to C-11) comprised the highest proportion of total finfish observations (n= 627), and were the second most abundant group of organisms observed across all ROV transects (Appendix B: Tables B-11 and B-12). GPS locations for flatfish are plotted in Appendix A: Figure A-5. On average, 35 flatfish were identified per transect, with an average density of 0.14 flatfish/m2 (Appendix B: Table B-12). Four species of flatfish were identified to species level: Pacific sanddab, Dover sole, rex sole (Glyptocephalus zachirus), and rock sole. The remaining 399 flatfish observations could not be classified past order (Appendix B: Table B-11). A total of 48 flatfish were observed buried in the sediment (11.4% of total flatfish observations), with an average density of 0.016 flatfish/m2 (Appendix B: Table B-12). Flatfish size calculations were possible for 34 individuals observed, (Appendix B: Table B-13), but statistical analyses based on size groupings could not be conducted due to low samples sizes.

Pacific sand lance (PSL)

No PSL were identified in any of the ROV transects.

Other

The ROV video analysis yielded 205 non-target bony finfish (superclass Osteichthyes) observations (Appendix B: Table B-11). Species observed included: Pacific snake prickleback (Lumpenus sagittal), sculpin sp. (superfamily Cottoidae), poacher sp. (family Agonidae), eelpout sp. (family Zoarcidae), brown

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Irish Lord (Hemilepidotus spinosus), goby sp. (family Gobiidae), codfish sp. (family Gadidae), plainfin midshipman (Porichthys notatus), and 38 observations of unknown bony finfish species (Appendix B: Table B-11). On average, the observed density of other bony finfish was 0.06 fish/m2 (Appendix B: Table B-12).

Incidental observations of cartilaginous fish (subclass Elasmobranchii) included 10 observations of egg cases from skate sp. (genus Raja) (Appendix C: Photo C-12). Spiny dogfish (Squalus suckleyi) were present in nine of the 12 transects surveyed (Appendix C: Photo C-13); however, due to their ease of movement they were not enumerated, only classified as present or absent (Appendix B: Table B-11).

4.2.1.2 Statistical Analyses: Habitat Associations

Observations (DGPS locations) of Dungeness crab and flatfish overlying the IDW interpolation map of geometric mean sediment size are presented in Appendix A: Figures A-6 and A-7, respectively.

Based on the two-way ANOVA results, there were statistically significant effects of depth and sediment grain size on orange sea pen densities, as well as a significant interaction of depth and sediment as a predictor of sea pen density (F9,15 = 6.86, P < 0.0001; Appendix B: Table B-14; Figures 8 and 9). Significant interaction effects of depth and sediment grain size were also found for the following species treatments:

 total Dungeness crab density (F9,15 = 2.54, P = 0.008);

 total flatfish density (F9,15 = 3.00, P = 0.002);

 non-buried flatfish density (F9,15 = 2.43, P = 0.011); and

 total finfish density (F9,15 = 4.54, P < 0.0001) (Appendix B: Table B-14).

There was a statistically significant difference in densities of taxa across depth strata for the following components:

 total Dungeness crab density (F3,15 = 5.45, P = 0.001);

 buried Dungeness crab density (F3,15 = 3.31, P = 0.020);

 non-buried Dungeness crab density (F3,15 = 3.26, P = 0.021), total crab density (F3,15 = 4.19, P = 0.006); and

 total finfish density (F3,15 = 3.13, P = 0.025) (Appendix B: Table B-14; Figure 8).

In addition to effects on orange sea pen density, sediment grain size effects were significant on only one other species treatment: total crab density (F3,15= 2.84, P = 0.037, Appendix B: Table 14; Figure 9).

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Orange sea pen densities were significantly higher in shallow depths (−5 to −10 m and −10 to −20 m) than deeper depths (−20 to −30 m and −30 to −40 m) with density generally decreasing with increasing depth (Figure 8 C). Both total Dungeness crab and total crab densities were significantly higher at −10 to −20 m depth (Figure 8 B). While total Dungeness crab and total crab density, which included Dungeness crabs, did not vary significantly with sediment grain size, the general pattern was one of highest crab densities in coarse sand and very fine sand (Figures 9 A and 9 B). Although not statistically significant, total flatfish and total finfish densities were highest at −20 to −30 m depth (Figures 8 D and 8 E) and in coarse sand (Figures 9 D and 9 E). Orange sea pen density was significantly higher in coarse sand (Figure 9 C).

Evidence for a significant effect of geographical location along the delta fore-slope was found for two species treatments (Appendix B: Table B-15 A): orange sea pen density (F2=104.93, P<0.0001) and total finfish density (F2=3.22, P=0.04) were significantly higher in Location 3 (Figure 3) compared to Locations 1 and 2, where densities did not significantly differ from each other (Figure 10). Pairwise comparisons of densities of species treatments inside and outside of the proposed RBT2 footprint and DZ revealed significantly higher densities of total Dungeness crab (driven by non-buried Dungeness crab; Appendix B: Table B-15 B) and orange sea pens inside the proposed RBT2 footprint and DZ, while total finfish density was significantly higher outside of the terminal footprint and DZ (Figure 11).

A weak negative relationship was noted between orange sea pen density and total finfish density (R2=0.013, P = 0.02, Figure 12). No significant relationships were found between orange sea pen density and the remaining species treatments (Appendix B: Table B-15 C).

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Figure 8 Bar Plots of the Density of each Species Treatment at Various Depth Zones

Note: A) Dungeness crabs, B) total crabs (all spp.), C) orange sea pens, D) flatfish, E) total finfish (all spp.). Different letters denote statistically significant differences between the four sediment grain size classifications for each species treatment, as determined by Tukey’s HSD. Absence of letters means no statistically significant differences were found for that species treatment group (e.g. D above). Error bars are standard error.

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Figure 9 Bar Plots of the Density of each Species Treatment at Different Sediment Grain Size Classifications

Note: A) Dungeness crabs, B) total crabs (all spp.), C) orange sea pens, D) flatfish, E) total fish (all spp.). Different letters denote statistically significant differences between the four sediment grain size classifications for each species treatment, as determined by Tukey’s HSD. Absence of letters means no statistically significant differences were found for that species treatment group (e.g., A, B, D, E above). Error bars are standard error.

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Figure 10 Bar Plot of the Species Treatment Densities at the Different Geographical Locations (1 to 3) along the Delta-front Slope at Roberts Bank (Figure 3)

Note: Letters denote statistically significant differences between locations as determined by Tukey’s HSD. Absence of letters means no statistically significant differences were found. Error bars are standard error.

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Figure 11 Bar Plot of Species Treatment Densities Inside and Outside of the Proposed RBT2 Footprint and Dredge Zone (DZ)

Note: Since species treatments 7 and 8 (i.e., buried and non-buried flatfish density, respectively; refer to Table 2) were not significantly different, they were combined as total flatfish density (Appendix B: Table B-15 B). Species treatments 2 and 3 are also combined as total Dungeness crab, the significance of which is driven by non-buried Dungeness crabs (Appendix B: Table B-15 B). *denotes statistically significant differences as determined by ANOVA (Appendix B: Table B-15). Error bars are standard error.

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Figure 12 Linear Regression of the Weak Negative Relationship between Orange Sea Pen Density and Total Finfish Density

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5.0 DISCUSSION

A discussion of the major results of the Marine Benthic Subtidal Study and data gaps are provided below.

5.1 DISCUSSION OF KEY FINDINGS

This study was intended to fill gaps in information about fish and invertebrate species occurring within the Benthic Subtidal Habitat Study area at Roberts Bank. Information is presented on the distribution, densities, and habitat preferences of key species. Results for the gravid female Dungeness crab and ROV surveys are discussed below.

5.1.1 Gravid Female Dungeness (SCUBA) Crab Survey

SCUBA surveys identified Dungeness crabs throughout the study area; however, gravid female crabs were observed at only three of twelve transect locations (Figure 2) and no gravid female aggregations were observed within the study area. Although densities of gravid female crabs occurring within brooding aggregations can be highly variable among populations (Stone and O’Clair 2002), the mean density of gravid crabs observed at Roberts Bank (0.008 crabs/m2) was considerably lower than estimates in other estuarine ecosystems where reported brooding crab densities ranged from 0.75 crabs/m2 (Scheding et al. 2001) to 20 crabs/m2 (Stone and O’Clair 2002). The estimated densities from this study are comparable to estimated gravid female crab densities from previous SCUBA surveys at locations peripheral to brooding aggregations (e.g., <0.02 crabs/m2, O’Clair et al. 1996; <1 crab/m2, Stone and O’Clair 2002).

The low number of gravid female crabs (n = 4) identified at Roberts Bank is unexpected, since the study area is dominated by sand sediments (verified by both direct SCUBA observations, ROV video review, and sediment grab analyses) predicted to support brooding habitats based on previously reported habitat preferences for female crabs (Diamond and Hankin 1985; O’Clair et al. 1996; Scheding et al. 2001; Stone and O’Clair 2001, 2002). While qualitative SCUBA and ROV video observations and quantitative sediment grab analyses indicated appropriate sediment for burying by gravid females, other habitat characteristics may be limiting burying. Alternately, gravid female Dungeness crabs at Roberts Bank may have habitat preferences different from those presented in the literature.

Survey depth might also explain the relatively low densities of gravid female crabs observed in this study. The majority of gravid female crabs identified in this study occurred within the deepest depth zone surveyed (−10 to −20 m CD) and at similar depths reported in Alaskan estuaries (Stone and O’Clair 2002); however, published accounts of preferred depths of gravid female aggregations vary widely, with one reporting aggregations in −10 m depth or less (Scheding et al. 2001) and another reporting mean depths of −16 to −26 m (Stone and O’Clair 2002). It is possible, therefore, that gravid females may be brooding in deeper water (i.e., beyond −18 m) at Roberts Bank, at depths beyond the reach of safe SCUBA dive limits. Measurements of water characteristics obtained in this study, including water

Port Metro Vancouver Hemmera RBT2 – Marine Benthic Subtidal Study - 47 - August 2014 temperature and salinity, are consistent with previously reported abiotic conditions within brooding locations (Stone and O’Clair 2002); however, deeper habitats might provide conditions more favorable for brooding eggs, as greater depths provide stability in temperature and salinity, and are typically well- oxygenated compared to shallower areas (Stone and O’Clair 2002).

Qualitative biophysical information collected during this survey (Appendix B: Table B-5) did not reveal major differences in sediment type, sediment features, or algal cover among transect locations with and without gravid crabs, although initial habitat observations indicated that female crabs prefer sand habitats compared to fine, muddy sediments. This observation is consistent with other studies that indicated sediment type is important in determining habitat quality for gravid female crabs and identified sand as the preferred substrate in which to brood eggs (Diamond and Hankin 1985; O’Clair et al. 1996; Scheding et al. 2001; Stone and O’Clair 2001, 2002). Sediments within brooding aggregations observed in southeast Alaska had relatively larger median particle size (0.192 mm) and were more homogenous with smaller proportions of silt and clay compared to sediment collected at locations where crabs did not aggregate (Stone and O’Clair 2002). In contrast, a second study in southeast Alaska (Scheding et al. 2001) identified female aggregations within finer sand sediments and found generally consistent grain size distributions among surveyed habitats with and without gravid crab aggregations, suggesting that habitat preference may vary among crab populations, even across relatively small spatial scales.

Due to small sample sizes, statistical analysis could not be used to assess whether a relationship existed between gravid crab densities (quantified in the SCUBA survey) and mean sediment grain size values estimated from the IDW interpolation map (Figure 5). Gravid females, however, were found in Location 3 along the delta-front slope (defined as a geographical stratum within the ROV survey component; Figure 3), which is characterised by the presence of larger grain sizes (0.25 to 2 mm) and the general absence of silt particles (4 µm to 0.0625 mm) relative to the rest of the study area (Figure 5). Congruent with the literature, this pattern in gravid female distribution suggests that coarser sandy substrates in Location 3 reflect biophysical characteristics that are optimal for gravid females and developing embryos, relative to other geographical strata (i.e., Locations 1 and 2) that are dominated by finer sand sediments (grain sizes 0.125 to 0.25 mm; Figure 5).

Low densities of gravid female crabs within the Roberts Bank study area may reflect a mismatch in the timing of the peak brooding season and the temporal scope of this study. The brood season for female Dungeness crabs in the Strait of Georgia is presumed to occur from October to March, as noted in DFO’s Manual for Crab Surveys in British Columbia (Dunham et al. 2011); however, other authors (Jaffe et al. 1987, Rasmuson 2013) have suggested that Dungeness crab eggs are extruded by females between September and February. While crabs remain relatively inactive during the winter, depth distributions become more variable towards the end of the brooding season as females begin to move into shallow water (<10 m) prior to egg hatching (Stone and O’Clair 2002). Dispersal into the intertidal appears to

Port Metro Vancouver Hemmera RBT2 – Marine Benthic Subtidal Study - 48 - August 2014 coincide with primary annual phytoplankton blooms and accompanying increased DO concentrations in shallow water, which may accelerate embryo development and initiate synchronous larval hatching (Stone and O’Clair 2002). The general lack of gravid female crabs within the study area may reflect sampling efforts coinciding with the end of the brooding season, rather than the peak, when aggregations are presumed to be the most dense (O’Clair et al. 1996, Stone and O’Clair 2002). Nevertheless, this study documented the presence of gravid female Dungeness crabs within the shallow subtidal habitat at Roberts Bank and, despite small sample sizes, has improved the current understanding of adult female crab distribution and relative abundance during the winter egg brooding period.

5.1.2 ROV Transect Survey

The ROV transect survey identified at least 10 macroinvertebrate species within the subtidal zone at Roberts Bank (Appendix B: Table B-11).

5.1.2.1 Dungeness Crabs

Post-survey video analyses indicated that Dungeness crabs were present throughout the study area. While sediment grain size did not play a major role in influencing total Dungeness crab (or total crab) density, depth effects were significant, with the highest densities occurring within the −10 to −20 m depth zone (Figure 8 A). Although depth variation likely accounts for the significant differences in total Dungeness crab density inside and outside the proposed RBT2 footprint and associated DZ, density did not differ significantly between the −10 to −20 m depth zone and the deepest depth zone (−30 to −40 m; Figure 8 A). The observed pattern in Dungeness crab distribution may reflect depth variation associated with diel migrations into the intertidal (i.e., adult crabs migrate daily to shallow intertidal flats to forage during nocturnal high tides) (Holsman et al. 2006, Curtis and McGaw 2012). Thus, sampling carried out during both slack and ebb tides may have captured crabs at intermediate depths, returning to deeper waters from shallow nearshore habitats where foraging typically takes place.

Although previously reported preferred depths of Dungeness adults vary widely among estuarine habitats (−10 to −230 m; Jensen 1995, Rasmuson 2013), the relatively higher densities of Dungeness crabs at intermediate and deep depths may reflect divergent depth-related preferences of male and female crabs. Previous field surveys at Puget Sound observed most non-gravid female Dungeness crabs at depths ranging from −20 to −80 m, while males were confined to shallow depths of −10 to −20 m (Armstrong et al. 1988). Classification of crabs by sex was not possible through ROV video analyses in this study.

5.1.2.2 Flatfish

Flatfish were observed at all depths within the study area (Figure 8 D), and comprised the highest proportion of finfish observations, consistent with previous surveys within the shallow subtidal (<25 m) at Roberts Bank (Triton 2004; Archipelago 2014a, 2014b); however, the survey did not observe or could not taxonomically classify all of the flatfish species known to be abundant in the subtidal area (e.g., starry

Port Metro Vancouver Hemmera RBT2 – Marine Benthic Subtidal Study - 49 - August 2014 flounder, English sole, sand sole, and butter sole) (Triton 2004, Archipelago 2014b). Alternative sampling methods used in previous surveys (i.e., benthic trawls) likely provided more accurate estimates of flatfish diversity. Nevertheless, consistent video observations of flatfish species inhabiting depths <25 m accentuate the importance of the subtidal zone as flatfish habitat at Roberts Bank.

Flatfish had the highest densities within the −20 to −30 m depth zone (Figure 8 D) and in coarse sand (Figure 9 D), although densities among depth zones and sediment types were not significantly different (Appendix B: Table B-14). The absence of significant effects was anticipated since flatfish occupy a wide range of soft bottom substrates including fine silt, mud, coarse sand, and cobble sediments, with preferences varying among species (Moles and Norcross 1995, Norcross et al. 1995, Stoner et al. 2007). In addition to variation among individual species, field studies have also documented intraspecific preferences for sediment grain sizes that vary with sex (e.g., English sole; Becker 1988) or with flatfish size, as it relates to life history stages (Moles and Norcross 1995, Gibson 1997, Phelan et al. 2001; Stoner and Ottmar 2003). Similarly, differences in depth-related habitat preferences have been documented for several species of flatfish (Norcross et al. 1999). For example, species such as adult Dover sole and rock sole are typically found in deeper waters (−200 to −300 m), sanddab species are common in shallower near-shore waters (<−150 m), and rex sole occupy a large bathymetric range (0 to −850 m) (McCain et al. 2005). Previously estimated densities of sanddab species, rock sole, and English sole at Roberts Bank were also shown to vary significantly with depth (Archipelago 2014b). Taken together, statistical analyses on flatfish as a group are unlikely to capture the full effect of habitat on individual flatfish species or specific life history stages.

Behavioral differences of individual flatfish species may have introduced variable detectability among species, thus hindering inference of positive habitat associations. Most of the flatfish observed were closely associated with the bottom sediment (e.g., within the ROV field of view); however, flatfish as a group are typically scattered throughout the water column at any one time. For example, common flatfish species such as English sole and rex sole heavily rely on epibenthic fauna as prey, while Pacific sanddab is mainly a pelagic forager, actively feeding on squid, small fish, shrimp copepods, larvae, and other plankton in the water column (McCain et al. 2005).

5.1.2.3 Finfish

Total density of finfish was highest over coarse sandy substrate (Figure 9 E). Although this difference was not significant, differences in sediment grain size composition among geographical locations along the delta-front slope (i.e., 1 to 3; Figure 3) may account for the significantly higher densities of finfish observed within Location 3 (Figure 10), which had a higher proportion of larger grain sizes (coarse; 0.25 to 2 mm) compared to Locations 1 and 2 (Figure 5). These results are consistent with previous studies at Roberts Bank, where higher densities of benthic finfish were associated with substrates dominated by sand rather than substrates that were a mixture of sand with mud and silt (Archipelago 2014b). Total finfish densities within Location 3 may also reflect higher recruitment from adjacent artificial reefs associated with the existing Westshore Terminals (Figure 3).

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While finfish were documented within all depth zones in the present study, significantly higher densities were found within deeper depths (−20 to −30 m; −30 to −40 m), compared to shallower (−5 to −10 m; −10 to −20 m) depth strata, suggesting that the observed differences in finfish density between areas inside and outside of the RBT2 footprint and associated DZ are likely explained by depth-related habitat associations (Figure 11).

5.1.2.4 Orange sea pens

The ROV surveys improved the current understanding of the geographic extent of sea pen habitat at Roberts Bank within the subtidal zone. Because of better depth capabilities associated with use of ROV for visual surveys, the present study identified sea pens within deeper areas (>−35 m; e.g., Transects 16 to 1, 17, and 24) where they have not been previously documented, due to depth limitations imposed by SIMS (Gartner Lee 1992, Triton 2004, Archipelago 2009, Hemmera and Archipelago 2014).

Orange sea pens exhibited significantly higher densities on coarse sediment substrates (0.25 to 2 mm grain size) within the study area (Figure 9 C). Differences in the composition of sediment grain size among geographical locations along the delta-front slope may account for the significantly higher densities of sea pens within Location 3 (Figure 10). The higher proportion of larger grain sizes (coarse; 0.25 to 2 mm), coupled with the limited distribution of silt particles (4 um to 0.0625 mm) throughout this region may explain the variability in the spatial distribution of orange sea pens. In previous studies at Roberts Bank, orange sea pens were consistently observed within mixed sand and diatom covered bottom substrates, and were largely absent from finer clay and diatom patches (Triton 2004, Archipelago 2009, Hemmera and Archipelago 2014). Laboratory experiments by Chia and Crawford (1973) suggested that although sand particle size did not have a major effect on sea pen larval settlement, the two key factors determining the locations where larvae choose to settle appeared to be availability of coarse sandy sediments and presence of other sea pens (i.e., sediment covered with adult sea pen secretions). Bottom current speeds may also contribute to sea pens habitat choice, as sea pens rely on the speed of ambient water flow for feeding efficiency, such that water flow passing through the body of the sea pen is maximised without causing physically deformation or uprooting (Best 1988). Within the Strait of Georgia, orange sea pens are among the dominant macrofauna along sloped substrates subjected to moderate to strong tidal outflows and oceanic currents (Levings et al. 1983, Burd et al. 2008). Differences in other physical and biological factors not addressed in the present study (e.g., bottom current speed), may also contribute to the sea pen distribution patterns observed along the delta-front slope.

Depth variation also influenced the occurrence of sea pens throughout the study area. Sea pen densities were significantly higher in shallow depths (−5 to −10 m and −10 to −20 m), compared to deeper depths (−20 to −30 m and −30 to −40 m; Figure 8), which is consistent with the depth distribution of previously documented sea pen aggregations observed between depths of −2.5 and −18 m within the terminal footprint (Gartner Lee 1992, Triton 2004, Archipelago 2009). Shallow subtidal habitat

Port Metro Vancouver Hemmera RBT2 – Marine Benthic Subtidal Study - 51 - August 2014 encompassing the terminal footprint may provide favourable conditions for larval settlement and adult persistence across longer temporal scales. Depth–related habitat preferences may explain sea pen densities inside and outside of the RBT2 footprint and associated DZ, which revealed significantly higher densities of sea pens within the Project footprint (Figure 11).

Equivocal evidence was found for significantly lower finfish densities with increasing sea pen density. This relationship was very weak (r2 = 0.013), and potentially reflective of observational techniques that were not specifically designed to examine this relationship. In particular, the highest finfish densities were observed when sea pen densities were in the range of 0.5/m2, with lower finfish densities on average in areas devoid of seapens, and at sea pen densities greater than 1.0/m2 (Figure 12). It is possible that finfish were obscured from view at the highest sea pen densities encountered.

Sea pen beds are known to provide structural complexity offering shelter from seafloor currents and predation for a diversity of benthic species in otherwise open, sand-dominated habitats with little physical refuge (Fuller et al. 2008, Buhl-Mortensen et al. 2010). The observed relationship is inconsistent with previous surveys at Roberts Bank. Towed underwater video and dive surveys in 2003, 2008, and 2011 frequently observed several fish species within areas covered by sea pen beds, including lingcod, kelp greenling, and spiny dogfish (Triton 2004, Archipelago 2009, Hemmera and Archipelago 2014). Likewise, field surveys in 2013 identified positive effects of sea pen distribution on overall fish density, with higher densities in areas with moderate to dense sea pen beds, compared to areas with patchy sea pen distributions (Archipelago 2014b). More specifically, rock sole and sanddab species were the primary species observed in sea pens beds and showed a positive association with sea pens density, while English sole showed no significant associations with sea pen beds (Archipelago 2014b). Indeed, rock sole (Stoner and Ottmar 2003, Stoner and Titgen 2003, Stoner et al. 2007) and sanddab species (Rackowski and Pikitch 1989) are known to be frequently associated with emergent structures, and have been shown to be less vulnerable to predation in these habitats (Ryer et al. 2004).

5.2 DATA GAPS AND LIMITATIONS

Relatively poor visibility and strong currents during the SCUBA survey created challenging conditions for detecting crabs, and likely hampered sampling efficiency. Furthermore, gravid females can be difficult to locate as they tend to bury into the sediment, with only their eye stalks and/or mouth parts visible. It is also possible that crabs were disturbed by the presence of the divers and buried further into the sediment. Gravid females have been found buried as deep as 0.5 m within the sediment (Scheding et al. 2001). As a result, some crab were likely overlooked by the divers and not counted, leading to under estimates of crab density.

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Male crabs are generally more active than females (Schultz et al. 1996), increasing the probability of detection; therefore, crab densities in this study may have been biased towards males., Brooding females have been reported to simultaneously emerge from the sediment, reducing visibility (by stirring sediments into the water column) and rapidly dispersing when disturbed by predators or other disturbance (Scheding et al. 2001, Stone and O’Clair 2002).; therefore, it is possible that the majority of crabs that scattered quickly when approached by divers (and could not be classified by sex; unknown sex category; Table 3) were females.

Although the ROV provided a useful platform for obtaining habitat and species (or species group) density data from subtidal habitat at Roberts Bank, biases inherent with underwater visual surveying, coupled with poor visibility, likely limited detection of burying species. Although numerous long transects were conducted to increase the probability of encountering cryptic species, total counts of flatfish and Dungeness crabs buried within the sediment were consistently lower relative to the number of non-buried observations. This discrepancy may have also resulted from fish avoidance or attraction behaviors associated with ROV lights, which were not accounted for in this study, and may have contributed to an underestimation of the proportion of individuals or species that had a greater tendency to remain buried. Similarly, as smaller juvenile flatfish tend to reside within shallow water (Phelan et al. 2001), lower densities of flatfish observed within the shallower depth zones (−5 to −10 m and −10 to −20 m) may reflect detection bias related to flatfish size, as observations through video recordings may not provide sufficient capacity to detect young flatfish typically buried in the sediments.

The PSL was not observed in the present ROV survey, possibly due to inherent sampling difficulties for PSL associated with their complex life history. Because PSL exhibit alternating benthic burrowing and pelagic foraging behaviors (Haynes 2006, Haynes et al. 2008), the field of view of the ROV camera, which is confined close to the bottom substrate, may have limited observations of PSL feeding higher up in the water column. During daytime in the summer when zooplankton are abundant, PSL occur in foraging schools in the water column, whereas burrowing behaviour occurs mostly during the night and in the winter (Field 1988, Robards and Piatt 1999). Moreover, poor visibility may generally limit the ability of observers to detect small burrowing fish, such as PSL, either in or on the surface of the sediment. Adult PSL are approximately 15 to 20 cm total length (Pinto et al. 1984), and mean burying depth within the sediment is 5.0 cm (range 4.0 to 6.0 cm) (Quinn 1999), leaving only approximately 10 to 15 cm of fish visible for observation. While previous observations confirmed the presence of PSL within the subtidal zone (Archipelago 2014b), significant data gaps remain with regard to PSL abundance, densities, and the extent of suitable PSL burying habitat within the Roberts Bank study area.

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Non-parametric methods were employed to analyse data collected during the gravid female Dungeness crab survey, as the survey data violated the assumption of normal distribution, which is required for parametric statistics. Non-parametric statistics make fewer assumptions, have wider applicability, and are more robust, but in cases where a parametric test would be appropriate, non-parametric tests have less power (higher chance of incurring a Type II error (i.e., a failure to detect an effect that is present)). For example, a larger sample size may be necessary to draw conclusions with the same degree of confidence as a parametric test. Results presented here for the gravid female Dungeness crab survey component of this study should be interpreted with caution, therefore.

For ROV survey data, a series of one-way ANOVAs as used to assess differences in density: 1) between delta-front slope locations; and 2) inside and outside the proposed RBT2 footprint and DZ, as statistical power was lacking to perform multivariate ANOVAs. Thus, the actual level of significance may have been lower than captured in individual probability values as a result of multiple comparisons. Furthermore, interactive effects of delta-front slope location and position inside or outside of the proposed RBT2 footprint were not formally examined.

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6.0 CLOSURE

Major authors and reviewers of this technical data report are listed below, along with their signatures.

Report prepared by: Hemmera Envirochem Inc.

Romney McPhie, M.Sc. Biologist

Iva Popovic, M.Sc. Biologist

Laura White, PhD. Marine Biologist and Technical Specialist

Marina Winterbottom, MMM. Marine Biologist

Report peer reviewed by: Hemmera Envirochem Inc.

Doug Bright, PhD, R.P.Bio., P.Biol. Practice Leader - Environmental Risk Assessment

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7.0 REFERENCES

Adams, P. B., J. L. Butler, C. H. Baxter, T. E. Laidig, K. A. Dahlin, and W. W. Wakefield. 1996. Population estimates of Pacific coast groundfishes from video transects and swept-area trawls. Oceanographic Literature Review 43.

Agler, B. A., S. J. Kendall, D. B. Irons, and S. P. Klosiewski. 1999. Declines in marine bird populations in Prince William Sound, Alaska coincident with a climatic regime shift. Waterbirds 98–103.

Archipelago. 2009. Section 10: Seapen bed interpretation; Section 11; Lingcod egg mass survey. In: Hemmera 2009. T2 environmental baseline montoring report. Prepared for Vancouver Port Authority. Vancouver, B.C.

Archipelago. 2011. CCIP Habitat offsetting: Sea pen survey and literature review. Prepared by Archipelago Marine Research Ltd. for Hemmera Envirochem Inc.

Archipelago Marine Research. 2014a. Roberts Bank Terminal 2 technical data report: Marine fish habitat characterisation. Prepared for Hemmera, Vancouver, B.C. Available at: http://www.robertsbankterminal2.com/

Archipelago Marine Research. 2014b. Roberts Bank Terminal 2 technical data report: Benthic fish trawl survey. Prepared for Hemmera, Vancouver, B.C. Available at: http://www.robertsbankterminal2.com/

Archipelago Marine Research. 2014c. Roberts Bank Terminal 2 technical data report: Juvenile salmon surveys. Prepared for Hemmera, Vancouver, B.C. Available at: http://www.robertsbankterminal2.com/.

Archipelago Marine Research. 2014d. Roberts Bank Terminal 2 technical data report: Eelgrass fish community survey. Prepared for Hemmera, Vancouver, B.C. Available at: http://www.robertsbankterminal2.com/

Archipelago Marine Research. 2014e. Roberts Bank Terminal 2 technical data report: Forage fish beach spawn survey. Prepared for Hemmera, Vancouver, B.C. Available at: http://www.robertsbankterminal2.com/

Armstrong, D. A., L. Botsford, and G. Jamieson. 1989. Ecology and population dynamics of juvenile Dungeness crab in Grays Harbour estuary and adjacent nearshore waters of the southern Washington Coast. Report to the U.S. Army Corps of Engineers, Seattle District.

Armstrong, D., J. Armstrong, and P. Dinnel. 1988. Distribution, abundance and habitat associations of Dungeness crab, Cancer magister, in Guemes Channel, San Juan Islands, Washington. Journal of Shellfish Research 7:147–148.

Assis, J., B. Claro, A. Ramos, J. Boavida, and E. Serrão. 2013. Performing fish counts with a wide-angle camera, a promising approach reducing divers’ limitations. Journal of Experimental Marine Biology and Ecology 445:93–98.

Becker, D. S. 1988. Relationship between sediment character and sex segregation in English sole, Parophrys vetulus. Fishery Bulletin 86:517–524.

Bernard, A., A. Götz, S. Kerwath, and C. Wilke. 2013. Observer bias and detection probability in underwater visual census of fish assemblages measured with independent double-observers. Journal of Experimental Marine Biology and Ecology 443:75–84.

Port Metro Vancouver Hemmera RBT2 – Marine Benthic Subtidal Study - 56 - August 2014

Best, B. A. 1988. Passive suspension feeding in a sea pen: Effects of ambient flow on volume flow rate and filtering efficiency. The Biological Bulletin 175:332–342.

Brodeur, R. D. 1990. A synthesis of the food habits and feeding ecology of salmonids in marine waters of the North Pacific. INPFC Document FRI-UW-9016, Fisheries Research Institute, University of Washington, Seattle, WA.

Brown, A. C., and N. B. Terwilliger. 1992. Developmental changes in ionic and osmotic regulation in the Dungeness crab, Cancer magister. The Biological Bulletin 182:270–277.

Buhl‐Mortensen, L., A. Vanreusel, A. J. Gooday, L. A. Levin, I. G. Priede, P. Buhl‐Mortensen, H. Gheerardyn, N. J. King, and M. Raes. 2010. Biological structures as a source of habitat heterogeneity and biodiversity on the deep ocean margins. Marine Ecology 31:21–50.

Bunte, K., and S. R. Abt. 2001. Sampling surface and subsurface particle-size distributions in wadable gravel-and cobble-bed streams for analyses in sediment transport, hydraulics, and streambed monitoring. U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fort Collins, CO, USA.

Burd, B. J., R. W. Macdonald, S. C. Johannessen, and A. van Roodselaar. 2008. Responses of subtidal benthos of the Strait of Georgia, British Columbia, Canada to ambient sediment conditions and natural and anthropogenic depositions. Marine Environmental Research 66:S62–S79.

Burke, J., Selden, J. M. Miller, and D. E. Hoss. 1991. Immigration and settlement pattern of Paralichthys dentatus and P. lethostigma in an estuarine nursery ground, North Carolina, USA. Netherlands Journal of Sea Research 27:393–405.

Busby, M. S., K. L. Mier, and R. D. Brodeur. 2005. Habitat associations of demersal fishes and crabs in the Pribilof Islands region of the Bering Sea. Fisheries Research 75:15 – 28.

Chan, F., J. Barth, J. Lubchenco, A. Kirincich, H. Weeks, W. Peterson, and B. Menge. 2008. Emergence of anoxia in the California Current large marine ecosystem. Science 319:920–920.

Chia, F. S., and B. J. Crawford. 1973. Some observations on gametogenesis, larval development and substratum selection of the sea pen Ptilosarcus gurneyi. Marine Biology 23:73–82.

Cleaver, F. C. 1949. Preliminary results of the coastal crab (Cancer magister) investigation. Biological Report, Washington State Department of Fisheries, Olympia, WA.

CMN. 2013. Burrard Inlet Environmental Action Program and Fraser River Estuary Management Program atlas. Community Mapping Network FREMP - BIEAP Habitat Atlas. .

Curtis, D. L., and I. J. McGaw. 2012. Salinity and thermal preference of Dungeness crabs in the lab and in the field: Effects of food availability and starvation. Journal of Experimental Marine Biology and Ecology 413:113–120.

Curtis, D., and I. McGaw. 2008. A year in the life of a Dungeness crab: Methodology for determining microhabitat conditions experienced by large decapod crustaceans in estuaries. Journal of Zoology 274:375–385.

DFO. 2012. Pacific Region Integrated Fisheries Management Plan: Crab by Trap January 1, 2012 - December 31, 2012. Integrated Fisheries Management Plan.

Port Metro Vancouver Hemmera RBT2 – Marine Benthic Subtidal Study - 57 - August 2014

Diamond, N., and D. G. Hankin. 1985. Movements of adult female Dungeness crabs (Cancer magister) in northern California based on tag recoveries. Canadian Journal of Fisheries and Aquatic Sciences 42:919–926.

Dick, M. H., and I. M. Warner. 1982. Pacific sand lance Ammodytes hexapterus Pallas, in the Kodiak Island group, Alaska. Syesis 15:43–50.

Dumbauld, B. R., and D. A. Armstrong. 1987. Potential mitigation of juvenile Dungeness crab loss during dredging through enhancement of intertidal shell habitat in Grays Harbor, WA.

Dunham, J. S., A. Phillips, J. Morrison, and G. Jorgensen. 2011. A manual for Dungeness crab surveys in British Columbia. Canadian Technical Report of Fisheries and Aquatic Sciences 2964.

ESRI. 2014. GIS Dictionary. .

Fernandez, M., O. Iribarne, and D. A. Armstrong. 1993. Habitat selection by young-of-the-year Dungeness crab, Cancer magister, and predation risk in intertidal habitats. Marine Ecology Progress Series 92:171–177.

Field, L. J. 1988. Pacific sand lance, Ammodytes hexapterus, with notes on related Ammodytes species. Species synopsis: Life histories of selected fish and shellfish of the northeast Pacific and Bering Sea 15–33.

Ford, J. K. B., and G. M. Ellis. 2006. Selective foraging by fish-eating killer whales Orcinus orca in British Columbia. Marine Ecology Progress Series 316:185–199.

Fuller, S. D., F. J. Murillo Perez, V. Wareham, and E. Kenchington. 2008. Vulnerable marine ecosystems dominated by deep-water corals and sponges in the NAFO Convention Area. Northwest Atlantic Fisheries Organization.

Gartner Lee. 1992. Environmental appraisal of proposed terminal, Roberts Bank. Prepared by Gartner Lee Ltd., Prepared for Vancouver Port Corporation, Burnaby, B.C.

Gibson, R. N. 1994. Impact of habitat quality and quantity on the recruitment of juvenile flatfishes. Netherlands Journal of Sea Research 32:191–206.

Gibson, R. N. 1997. Behaviour and the distribution of flatfishes. Journal of Sea Research 37:241–256.

Gray, J. S. 1981. The ecology of marine sediments: An introduction to the structure and function of benthic communities. CUP Archive.

Greenstreet, S. P. R., G. J. Holland, E. J. Guirey, E. Armstrong, H. M. Fraser, and I. M. Gibb. 2010. Combining hydroacoustic seabed survey with grab sampling techniques to assess “local” Sandeel population abundance. ICES Journal of Marine Science 67:971–984.

Greer, G. L., C. D. Levings, R. Harbo, B. Hillaby, T. Brown, and J. Sibert. 1980. Distribution of fish species on Roberts and Sturgeon banks recorded in seine and trawl surveys. Canadian Manuscript Report of Fisheries and Aquatic Sciences, No. 1596, Fisheries and Oceans Canada, West Vancouver, B.C.

Gunderson, D. R., D. A. Armstrong, Y.-B. Shi, and R. A. McConnaughey. 1990. Patterns of estuarine use by juvenile English sole (Parophrys vetulus) and Dungeness crab (Cancer magister). Estuaries 13:59–71.

Port Metro Vancouver Hemmera RBT2 – Marine Benthic Subtidal Study - 58 - August 2014

Hankin, D. G. N., N. Diamond, S. Mohr, and J. Ianelli. 1989. Growth and reproductive dynamics of adults female Dungeness crabs (Cancer magister) in northern California. Journal du Conseil et International Exploration de la Mer 46:94–108.

Hart, J. 1973. Pacific fishes of Canada. Bull. Fish. Res. Board Can 180:740.

Haynes, T. B., C. K. L. Robinson, and P. Dearden. 2008. Modelling nearshore intertidal habitat use of young-of-the-year Pacific sand lance (Ammodytes hexapterus) in Barkley Sound, British Columbia, Canada. Environmental Biology of Fishes 83:473–484.

Haynes, T. B., and C. K. L. Robinson. 2011. Re-use of shallow sediment patches by Pacific sandlance (Ammodytes hexapterus) in Barkley Sound, British Columbia. Environmental Biology of Fishes 92:1–12.

Haynes, T. B., R. A. Ronconi, and A. E. Burger. 2007. Habitat use and behavior of the Pacific sand lance (Ammodytes hexapterus) in the shallow subtidal region of southwestern Vancouver Island. Northwestern Naturalist 88:155–167.

Haynes, T. B. 2006. Modeling habitat use of young-of-the-year Pacific sand lance (Ammodytes hexapterus) in the nearshore region of Barkley Sound, British Columbia. M.Sc. Thesis, University of Victoria, Department of Geography, Victoria, B.C.

Hedd, A., D. F. Bertram, J. L. Ryder, and I. L. Jones. 2006. Effects of interdecadal climate variability on marine trophic interactions: Rhinoceros auklets and their fish prey. Marine Ecology Progress Series 309:263–278.

Hemmera and Archipelago. 2014. Roberts Bank Terminal 2 technical data report: Orange sea pens (Ptilosarcus gurneyi). Prepared for Port Metro Vancouver, Vancouver, B.C. Available at: http://www.robertsbankterminal2.com/

Hemmera. 2014a. Roberts Bank Terminal 2 technical data report: Juvenile Dungeness crabs. Prepared for Port Metro Vancouver, Vancouver, B.C. Available at: http://www.robertsbankterminal2.com/

Hemmera. 2014b. Roberts Bank Terminal 2 technical data report: Sediment and water quality characterisation studies. Prepared for Port Metro Vancouver, Vancouver, B.C. in Port Metro Vancouver (PMV). 2015. Roberts Bank Terminal 2 Environmental impact statement: Volume 2. Environmental Assessment by Review Panel. Submitted to Canadian Environmental Assessment Agency.

Hemmera. 2014c. Roberts Bank Terminal 2 technical report: Habitat suitability modelling study. Prepared for Port Metro Vancouver, Vancouver, B.C. in Port Metro Vancouver (PMV). 2015. Roberts Bank Terminal 2 Environmental impact statement: Volume 3. Environmental Assessment by Review Panel. Submitted to Canadian Environmental Assessment Agency.

Hixon, M. A., and B. N. Tissot. 2007. Comparison of trawled vs untrawled mud seafloor assemblages of fishes and macroinvertebrates at Coquille Bank, Oregon. Journal of Experimental Marine Biology and Ecology 344:23–34.

Holland, G. J., S. P. R. Greenstreet, I. M. Gibb, H. M. Fraser, and M. R. Robertson. 2005. Identifying sandeel Ammodytes mainus sediment habitat preferences in the marine environment. Marine Ecology Progress Series 303:269 – 282.

Holsman, K. K., D. A. Armstrong, D. A. Beauchamp, and J. L. Ruesink. 2003. The necessity for intertidal foraging by estuarine populations of subadult Dungeness crab, Cancer magister: Evidence from a bioenergetics model. Estuaries 26:1155–1173.

Port Metro Vancouver Hemmera RBT2 – Marine Benthic Subtidal Study - 59 - August 2014

Holsman, K. K., P. S. McDonald, and D. A. Armstrong. 2006. Intertidal migration and habitat use by subadult Dungeness crab Cancer magister in a NE Pacific estuary. Marine Ecology Progress Series 308:183–195.

Hurst, T. P., and A. A. Abookire. 2006. Temporal and spatial variation in potential and realized growth rates of age-0 year northern rock sole. Journal of fish biology 68:905–919.

Hurst, T. P., C. H. Ryer, J. M. Ramsey, and S. A. Haines. 2007. Divergent foraging strategies of three co- occurring north Pacific flatfishes. Marine Biology 151:1087 – 1098.

Jaffe, L., C. Nyblade, R. Forward, and S. Sulkin. 1987. Phylum or subphylum Crustacea, class Malacostraca, Order Decapoda, Brachyura. Strathmann, M. (Ed.), Reproductive and Development of marine invertebrates of the northern Pacific Coast: Data and methods for the study of eggs, embryos and larvae. University of Washington Press, Seattle, Washington.

Jamieson, G. S., and A. Phillips. 1993. Megalopal spatial distribution and stock separation in Dungeness crab (Cancer magister). Canadian Journal of Fisheries and Aquatic Science 50:416–429.

Jensen, G. C., and D. A. Armstrong. 1987. Range extensions of some northeastern Pacific Decapoda. Crustaceana 215–217.

Jensen, G. 1995. Pacific coast crabs and shrimps. Sea challengers. Inc., Monterey.

Jensen, P. C., J. M. Orensanz, and D. A. Armstrong. 1996. Structure of the female reproductive tract in the Dungeness crab (Cancer magister) and implications for the mating system. The Biological Bulletin 190:336–349.

Johnson, S. W., M. L. Murphy, and D. J. Csepp. 2003. Distribution, habitat, and behavior of rockfishes, Sebastes spp., in nearshore waters of southeastern Alaska: Observations from a remotely operated vehicle. Environmental Biology of Fishes 66:259–270. van der Kooij, J., B. E. Scott, and S. Mackinson. 2008. The effects of environmental factors on daytime sandeel distribution and abundance on the Dogger Bank. Journal of Sea Research 60:201–209.

Kramer, D. E., W. H. Barss, B. C. Paust, and B. E. Bracken. 1995. Northeast Pacific flatfishes. Marine Advisory Bulletin 47, Alaska Sea Grant College Program and Alaska Fisheries Development Foundation.

Lamb, A., and B. P. Hanby. 2005. Marine life of the Pacific Northwest: A photographic encyclopedia of invertbrates, seaweeds and selected fishes. Harbour Publishing, Madeira Park, CB.

Lemke, J. L., and C. H. Ryer. 2006. Relative predation vulnerability of three juvenile (Age-0) North Pacific flatfish species: Possible influence of nursery-specific predation pressures. Morine Ecology Progress Series 328:267.

Levings, C. D., R. E. Foreman, and V. J. Tunnicliffe. 1983. Review of the benthos of the Strait of Georgia and contiguous fjords. Canadian Journal of Fisheries and Aquatic Sciences 40:1120–1141.

Macer, C. 1966. Sand eels (Ammodytidae) in the south-western North Sea; Their biology and fishery.

Mackas, D., M. Galbraith, D. Faust, D. Masson, K. Young, W. Shaw, S. Romaine, M. Trudel, J. Dower, R. Campbell, A. Sastri, E. A. Bornhold Pechter, E. Pakhomov, and R. El-Sabaawi. 2013. Zooplankton time series from the Strait of Georgia: Results from year-round sampling at deep water locations, 1990–2010. Progress in Oceanography 115:129–159.

Port Metro Vancouver Hemmera RBT2 – Marine Benthic Subtidal Study - 60 - August 2014

MacKenzie, C. J. 2010. The Dungeness crab (Metacarcinus magister) fishery in Burrard Inlet, B.C: Constraints on abundance-based management and improved access for recreational harvesters. MRM project report. Simon Fraser University, Burnaby 92.

Marliave, J., and W. Challenger. 2009. Monitoring and evaluating rockfish conservation areas in British Columbia. Canadian Journal of Fisheries and Aquatic Sciences 66:995–1006.

Mayer, D. L. 1979. The ecology and thermal sensitivity of the Dungeness crab, Cancer magister, and related species of its benthic community in Similk Bay, Washington. Ph.D. Thesis, University of Washington.

McCain, B. B., S. D. Miller, and W. W. L. Cheung. 2005. Life history, geographical distribution, and habitat associations of 82 west coast groundfish species: A literature review. Pacific Coast Groundfish Fishery Management Plan for the California, Oregon, and Washington Groundfish Fishery, Appendix B, Part 2, Groundfish Life History Descriptions, Pacific Fishery Management Council, Portland, OR.

McConnaughey, R. A., D. A. Armstrong, B. M. Hickey, and D. R. Gunderson. 1992. Juvenile Dungeness crab (Cancer magister) recruitment variability and oceanic transport during the pelagic larval phase. Canadian Journal of Fisheries and Aquatic Sciences 49:2028–2044.

McConnaughey, R. A., D. A. Armstrong, and B. M. Hickey. 1995. Dungeness crab (Cancer magister) recruitment variability and Ekman transport of larvae. Pages 167–174 in. Volume 199. Copenhagen, Denmark: International Council for the Exploration of the Sea, 1991-.

McGaw, I. J. 2005. Burying behaviour of two sympatric crab species: Cancer magister and Cancer productus. Scientia Marina 69:375–381.

McMillan, R. O., D. A. Armstrong, and P. A. Dinnel. 1995. Comparison of intertidal habitat use and growth rates of two northern Puget Sound cohorts of 0+ age Dungeness crab, Cancer magister. Estuaries 18:390–398.

Meyer, T. L., R. A. Cooper, and R. W. Langton. 1979. Relative abundance, behavior, and food habits of the American sand lance, Ammodytes americanus, from the Gulf of Maine. Fishery Bulletin 77:243–253.

Moles, A., and B. L. Norcross. 1995. Sediment preference in juvenile Pacific flatfishes. Netherlands Journal of Sea Research 34:177–182.

Norcross, B. L., A. Blanchard, and B. A. Holladay. 1999. Comparison of models for defining nearshore flatfish nursery areas in Alaskan waters. Fisheries Oceanography 8:50–67.

Norcross, B. L., B. A. Holladay, and F. J. Müter. 1995. Nursery area characteristics of pleuronectids in coastal Alaska, USA. Netherlands Journal of Sea Research 34:161–175.

Norcross, B. L., and F.-J. Mueter. 1999. The use of an ROV in the study of juvenile flatfish. Fisheries Research 39:241–251.

O’Clair, C. E., T. C. Shirley, and S. J. Taggart. 1996. Dispersion of adult Cancer magister at Glacier Bay, Alaska: Variation with spatial scale, sex, and reproductive status. Pages 209–227 in. High latitude crabs: Biology, management, and economics. University of Alaska Sea Grant, AK-SG-96-02, Fairbanks, Alaska.

Port Metro Vancouver Hemmera RBT2 – Marine Benthic Subtidal Study - 61 - August 2014

Orensanz, J. M., and V. F. Gallucci. 1988. Comparative study of postlarval life-history schedules in four sympatric species of Cancer (Decapoda: Brachyura: Cancridae). Journal of Crustacean Biology 8:187–220.

Ostrand, W. D., T. A. Gotthardt, S. Howlin, and M. D. Robards. 2005. Habitat selection models for Pacific sand lance (Ammodytes hexapterus) in Prince William Sound, Alaska. Northwest Naturalist 86:131–143.

Pacunski, R. E., W. A. Palsson, H. G. Greene, and D. Gunderson. 2008. Conducting visual surveys with a small ROV in shallow water. Marine Habitat Mapping Technology for Alaska 109–128.

Pacunski, R. E., W. A. Palsson, and H. G. Greene. 2013. Estimating fish abundance and community composition on rocky habitats in the San Juan Islands using a small remotely operated vehicle. Washington Department of Fish and Wildlife, Fish Program, Fish Management Division.

Pappal, A., R. Rountree, and D. MacDonald. 2012. Relationship between body size and habitat complexity preference in age‐0 and‐1 year winter flounder Pseudopleuronectes americanus. Journal of fish biology 81:220–229.

Parravicini, V., F. Micheli, M. Montefalcone, E. Villa, C. Morri, and C. N. Bianchi. 2010. Rapid assessment of epibenthic communities: A comparison between two visual sampling techniques. Journal of Experimental Marine Biology and Ecology 395:21–29.

Parry, D. M., M. A. Kendall, D. A. Pilgrim, and M. B. Jones. 2003. Identification of patch structure within marine benthic landscapes using a remotely operated vehicle. Journal of Experimental Marine Biology and Ecology Vol. 285-286:497–511.

Parry, D. M., L. A. Nickell, M. A. Kendall, M. T. Burrows, D. A. Pilgrim, and M. B. Jones. 2002. Comparison of abundance and spatial distribution of burrowing megafauna from diver and remotely operated vehicle observations. Marine Ecology Progress Series 244:89–93.

Pauley, G. B., D. A. Armstrong, R. Van Citter, and G. Thomas. 1989. Species profiles: Life histories and environmental requirements of coastal fishes and invertebrates (Pacific Southwest), Dungeness crab.

Pearson, D., S. Owen, and D. Thomas. 1992. English sole. Page 257 in. California’s living marine resources and their utilization. California Sea Grant College Program, Davis, California. UCSGEP-92-12:99–100.

Penttila, D. E. 1995. Investigations of the spawning habitat of the Pacific sand lance, Ammodytes hexapteru. Pages 855–859 in. Puget Sound Research-95 Conference Proceedings. Volume 2. Puget Sound Water Authority, Olympia, WA.

Penttila, D. 2007. Marine forage fishes in Puget Sound. Technical Report 2007-03, Washington Department of Fish and Wildlife.

Phelan, B., J. Manderson, A. Stoner, and A. Bejda. 2001. Size-related shifts in the habitat associations of young-of-the-year winter flounder (Pseudopleuronectes americanus): Field observations and laboratory experiments with sediments and prey. Journal of Experimental Marine Biology and Ecology 257:297–315.

Pinto, J. M., W. H. Pearson, and J. W. Anderson. 1984. Sediment preferences and oil contamination in the Pacific sand lance Ammodytes hexapterus. Marine Biology 83:193–204.

Port Metro Vancouver Hemmera RBT2 – Marine Benthic Subtidal Study - 62 - August 2014

Quinn, T. 1999. Habitat characteristics of an intertidal aggregation of Pacific sand lance (Ammodytes hexapterus) at a North Puget Sound beach in Washington. Northwest Science 73:44–49.

Rabaut, M., M. A. Calderón, L. Van de Moortel, J. van Dalfsen, M. Vincx, S. Degraer, and N. Desroy. 2013. The role of structuring benthos for juvenile flatfish. Journal of Sea Research 84:70–76.

Rackowski, J. P., and E. K. Pikitch. 1989. Species profiles: Life histories and environmental requirements of coastal fishes and invertebrates (Pacific Southwest): Pacific and speckled sanddabs. Prepared for the US Fish and Wildlife Service.

Rasmuson, L. K. 2013. The biology, ecology and fishery of the Dungeness crab, Cancer magister. Advances in Marine Biology 65:95–148.

Reay, P. 1970. Synopsis of biological data on North Atlantic sandeels of the genus Ammodytes (A. tobianus, A. dubius, A. americanus and A. marinus). Food and Agriculture Organization of the United Nations.

Richardson, J. S., T. J. Lissimore, M. C. Healey, and T. G. Northcote. 2000. Fish communities of the lower Fraser River (Canada) and a 21-year contrast. Environmental Biology of Fishes 59:125– 140.

Robards, M. D., and J. F. Piatt. 1999. Biology of the genus Ammodytes, the sand lances. USDA Forest Service Pacific Northwest Research Station Research Paper 1–16.

Robards, M. D., G. A. Rose, and J. F. Piatt. 2002. Growth and abundance of Pacific sand lance, Ammodytes hexapterus, under differing oceanographic regimes. Environmental Biology of Fishes 64:429–441.

Robards, M. D., M. F. Willson, R. H. Armstrong, and J. F. Piatt. 1999. Sand lance: A review of biology and predator relations and annotated bibliography. Exxon Valdez Oil Spill Restoration Project, PNW- RP 521, U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station, Portland, OR.

Robinson, C. L. K., D. Hrynyk, J. V. Barrie, and J. Schweigert. 2013. Identifying subtidal burying habitat of Pacific sandlance (Ammodytes hexapterus) in the Strait of Georgia, British Columbia, Canada. Progress in Oceanography 115:119–128.

Robinson, C. L., and J. Yakimishyn. 2013. The persistence and stability of fish assemblages within eelgrass meadows (Zostera marina) on the Pacific coast of Canada. Canadian Journal of Fisheries and Aquatic Sciences 70:775–784.

Roegner, G. C., D. A. Armstrong, and A. L. Shanks. 2007. Wind and tidal influences on larval crab recruitment to an Oregon estuary. Marine Ecology, Progress Series 351:177.

Rooper, C. N., D. A. Armstrong, and D. R. Gunderson. 2002. Habitat use by juvenile Dungeness crabs in coastal nursery estuaries. Crabs in Cold Water Regions: Biology, Management, and Economics Alaska Sea Grant College Program.

Rooper, C. N., D. R. Gunderson, and D. A. Armstrong. 2003. Patterns in use of estuarine habitat by juvenile English sole (Pleuronectes vetulus) in four eastern North Pacific estuaries. Estuaries 26:1142–1154.

Ryer, C. H., J. L. Lemke, K. Boersma, and S. Levas. 2008. Adaptive coloration, behavior and predation vulnerability in three juvenile north Pacific flatfishes. Journal of Experimental Marine Biology and Ecology 359:62–66.

Port Metro Vancouver Hemmera RBT2 – Marine Benthic Subtidal Study - 63 - August 2014

Ryer, C. H., A. W. Stoner, and R. H. Titgen. 2004. Behavioral mechanisms underlying the refuge value of benthic habitat structure for two flatfishes with differing anti-predator strategies. Marine Ecology Progress Series 268:231–243.

Scheding, K., T. Shirley, C. E. O’Clair, and S. J. Taggart. 2001. Critical habitat for ovigerous Dungeness crabs. Pages 431–445 in G. H. Kruse, B. Nicolas, A. Booth, M. W. Dorn, S. Hills, R. N. Lipcius, D. Pelletier, C. Roy, S. J. Smith, and D. Witherell, Editors. Spatial processes and management of marine populations. University of Alaska Sea Grant, AK-SG-01-02, Fairbanks, Alaska. . Accessed 14 Jan 2014.

Schultz, D., T. Shirley, C. O’Clair, and S. Taggart. 1996. Activity and feeding of ovigerous Dungeness crabs in Glacier Bay, Alaska. High latitude crabs: Biology, management, and economics. University of Alaska Sea Grant, AK-SG-96-02, Fairbanks 411–424.

Sinclair, E. H., and T. K. Zeppelin. 2002. Seasonal and spatial differences in diet in the western stock of Steller sea lions (Eumetopias jubatus). Journal of Mammalogy 83:973–990.

Stone, R., and C. O’Clair. 2001. Seasonal movements and distribution of Dungeness crabs Cancer magister in a glacial southeastern Alaska estuary. Marine Ecology Progress Series 214:167–176.

Stone, R. P., and C. E. O’Clair. 2002. Behavior of female Dungeness crabs, Cancer magister, in a glacial southeast Alaska estuary: Homing, brooding-site fidelity, seasonal movements, and habitat use. Journal of Crustacean Biology 22:481–492.

Stoner, A. W., and M. L. Ottmar. 2003. Relationships between size-specific sediment preferences and burial capabilities in juveniles of two Alaska flatfishes. Journal of experimental marine biology and ecology 282:85–101.

Stoner, A. W., M. L. Spencer, and C. H. Ryer. 2007. Flatfish-habitat associations in Alaska nursery grounds: Use of continuous video records for multi-scale spatial analysis. Journal of Sea Research 57:137–150.

Stoner, A. W., and R. H. Titgen. 2003. Biological structures and bottom type influence habitat choices made by alaska flatfishes. Journal of Experimental Marine Biology and Ecology 232:43–59.

Suryan, R. M., D. B. Irons, M. Kaufman, J. Benson, P. G. Jodice, D. D. Roby, and E. D. Brown. 2002. Short-term fluctuations in forage fish availability and the effect on prey selection and brood- rearing in the black-legged kittiwake Rissa tridactyla. Marine Ecology Progress Series 236:273– 287.

Swiney, K. M., T. C. Shirley, S. J. Taggart, and C. E. O’Clair. 2003. Dungeness crab, Cancer magister, do not extrude eggs annually in Southeastern Alaska: An in situ study. Journal of Crustacean Biology 23:280–288.

Therriault, T. W., D. E. Hay, and J. F. Schweigert. 2009. Biological overview and trends in pelagic forage fish abundance in the Salish Sea (Strait of Georgia, British Columbia). Marine Ornithology 37:3– 8.

Thuringer, P. L. 2004. Documenting Pacific sand lance (Ammodytes hexapterus) spawning habitat in Baynes Sound, east coast Vancouver Island, and the potential interactions with intertidal shellfish aquaculture. M.Sc. Thesis, Royal Roads University, Victoria, B.C.

Triton. 2004. Deltaport Third Berth Project marine resources impact assessment. Prepared by Triton Environmental Consultants Ltd., Prepared for Vancouver Port Authority, Richmond, B.C.

Port Metro Vancouver Hemmera RBT2 – Marine Benthic Subtidal Study - 64 - August 2014

Wentworth, C. K. 1922. A scale of grade and class terms for clastic sediments. The Journal of Geology 30:372–392.

Wild, P. W. 1980. Effects of seawater temperature on spawning, egg, development, hatching success, and population fluctuations of the Dungeness crab, Cancer magister. Temperature and Dungeness Crab Reproductive Biology, CalCOFI.

Winslade, P. 1974. Behavioural studies on the lesser sandeel Ammodytes marinus (Raitt) I. The effect of food availability on activity and the role of olfaction in food detection. Journal of Fish Biology 6:565–576.

Wouters, N., and H. N. Cabral. 2009. Are flatfish nursery grounds richer in benthic prey? Estuarine, Coastal and Shelf Science 83:613–620.

Wright, P. J., H. Jensen, and I. Tuck. 2000. The influence of sediment type on the distribution of the lesser sandeel, Ammodytes marinus. Journal of Sea Research 44:243–256.

Port Metro Vancouver Hemmera RBT2 – Marine Benthic Subtidal Study - 65 - August 2014

8.0 STATEMENT OF LIMITATIONS

This report was prepared by Hemmera Envirochem Inc. (“Hemmera”), based on fieldwork conducted by Hemmera, for the sole benefit and exclusive use of Port Metro Vancouver. The material in it reflects Hemmera’s best judgment in light of the information available to it at the time of preparing this Report. Any use that a third party makes of this Report, or any reliance on or decision made based on it, is the responsibility of such third parties. Hemmera accepts no responsibility for damages, if any, suffered by any third party as a result of decisions made or actions taken based on this Report.

Hemmera has performed the work as described above and made the findings and conclusions set out in this Report in a manner consistent with the level of care and skill normally exercised by members of the environmental science profession practicing under similar conditions at the time the work was performed.

This Report represents a reasonable review of the information available to Hemmera within the established Scope, work schedule and budgetary constraints. The conclusions and recommendations contained in this Report are based upon applicable legislation existing at the time the Report was drafted. Any changes in the legislation may alter the conclusions and/or recommendations contained in the Report. Regulatory implications discussed in this Report were based on the applicable legislation existing at the time this Report was written.

In preparing this Report, Hemmera has relied in good faith on information provided by others as noted in this Report, and has assumed that the information provided by those individuals is both factual and accurate. Hemmera accepts no responsibility for any deficiency, misstatement or inaccuracy in this Report resulting from the information provided by those individuals.

APPENDIX A Figures

Port Metro Vancouver APPENDIX A Hemmera RBT2 – Marine Benthic Subtidal Study - 1 - August 2014

Figure A-1 Diagram Illustrating the Remotely-Operated Vehicle Setup

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Figure A-2 Remotely-Operated Vehicle Survey DGPS Data Illustrating Outliers for Transect 13

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Figure A-3. Inverse Distance Weighted Interpolation of Coarse Sediment Classification for the Remotely-Operated Vehicle Survey

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Figure A-4. Observations of Dungeness Crabs (Metacarcinus magister) from the Remotely-Operated Vehicle Survey

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Figure A-5 Observations of Flatfish (Order Pleuronectiformes) from the Remotely-Operated Vehicle Survey

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Figure A-6 Observations of Dungeness Crabs (Metacarcinus magister) from the Remotely-Operated Vehicle Survey, Overlying the Fine Resolution Inverse Distance Weighted Interpolation of Geometric Mean Sediment Grain Size

Port Metro Vancouver APPENDIX A Hemmera RBT2 – Marine Benthic Subtidal Study - 7 - August 2014

Figure A-7 Observations of Flatfish (Order Pleuronectiformes) from the Remotely-Operated Vehicle Survey Overlying the Fine Resolution Inverse Distance Weighted Interpolation of Geometric Mean Sediment Grain Size

APPENDIX B Tables

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Table B-1 Habitat Characteristics and Classification Indices

Habitat Characteristics Classes

Silt – very fine, and easily disturbed in visible plumes by the ROV thrust propellers and moving organisms Substrate type Mud – noticeably more compact, with a slick appearance and a visible sheen on the surface, and is not disturbed by (dominant, per 30-sec transect interval) ROV movements Sand – is notably coarser with no visible sheen and usually appears as wavy bedforms Absent – completely clear of cover Broken shell hash Substrate cover Gravel-cobble (dominant, per 30-sec transect interval)1 Rocks-boulders Structural biota – macroalgae, sea pens, sponges etc. Simple – smooth, no crevices, bioturbation and/or current ripples Low complexity – less than 25% covered by crevices, bioturbation and/or current ripples Complexity % cover Medium complexity – 25 to 50% covered by crevices, bioturbation and/or current ripples) (per 30-sec transect interval) High complexity – more than 50% covered by crevices, bioturbation and/or current ripples Very high complexity – more than 75% covered by crevices, bioturbation and/or current ripples

1 Methodology derived from Norcross and Mueter 1999, Busby et al. 2005. Busby et al. (2005) used six habitat classifications based on video footage of substrate and cover: 1) silt; 2) mud; 3) sand with no cover; 4) silt, mud, or sand with broken shell hash; 5) silt, mud, or sand with gravel and/or cobble; and 5) silt, mud, or sand with rocks and/or boulders.

Port Metro Vancouver APPENDIX B Hemmera RBT2 – Marine Benthic Subtidal Study - 2 - August 2014

Table B-2 Summary of Remotely-Operated Vehicle Transect Characteristics Determined during Video Analyses and Relating to Calculations of Video Interval Time (t) (see Section 3.2.5.1 for details)

Total Total Total Total Time (Minus Interval Total Off Total Transect Transect Transect Distance On Transect Stoppage Stoppages) (T ) Time (t) Bottom Distance Off Start Time End Time Time (T ) t-stop Bottom (T ) t Time (sec) (sec) (sec) Time (sec) Bottom (m) L (sec) (m) 13 8:21:02 8:57:50 2208 255 1953 48 53 11.2 399.9 14 7:25:47 8:14:38 2931 726 2205 56 65 11.6 382.4 15 7:55:44 8:40:43 2699 246 2453 61 26 4.24 395.8 16-1 12:51:37 13:22:58 1881 22 1859 45 0 0 416.0 17 12:39:24 13:10:00 1836 56 1780 44 0 0 407.0 18 11:09:21 11:54:03 2682 611 2071 51 19 3.70 399.3 19 9:11:13 10:08:24 3435 1181 2254 56 54 9.63 392.4 20 10:49:53 11:20:20 1827 65 1762 44 0 0 404.0 21-1 9:02:19 9:39:10 2211 285 1926 48 32 6.70 396.3 22 12:14:10 12:52:34 2304 152 2152 51 32 6.29 416.7 23 10:05:12 10:35:41 1829 123 1706 42 0 0 402.0 24 11:44:38 12:18:57 2059 159 1900 47 0 0 405.0 Average 2325 323 2002 49 23 4.4 401.4 SD 513.0 346.2 227.4 5.8 24.2 4.6 9.6 Total 27902 3881 24021 593 281 53.3 4816.7

Port Metro Vancouver APPENDIX B Hemmera RBT2 – Marine Benthic Subtidal Study - 3 - August 2014

Table B-3 Summary of Gravid Female Dungeness Crab (SCUBA) Survey Transect Characteristics and Observed Non-target Organisms

Maximum Depth Other Organisms Date Depth Visibility 2 Bioturb/ Crab Sea Pen 3 Transect 1 Slope Observed Surveyed Strata (m) (m) (m CD) (m) Ripple (%) Traps (#) (#) Jan 29 1 0 to −5 4.90 1.70 10 flat 30/70 0 6 - Jan 28 2 0 to −5 5.20 1.90 8 flat 10/90 0 15 - starry flounder, giant Jan 28 3 0 to −5 6.70 3.30 8 low 5/95 0 200 nudibranch starry flounder, sunflower Jan 29 4 0 to −5 5.80 1.90 4 flat 0/100 0 1 sea star Jan 29 5 −5 to −10 12.2 9.10 8 low 10/85 0 7 - Jan 26 6 −5 to −10 8.80 4.90 13 flat 5/95 1 10 sunflower sea star sunflower sea star, pink sea Jan 28 7 −5 to −10 12.5 9.00 3 low 5/95 0 40 star, striped sea star, plumose anemone longnose skate, starry Jan 28 8 −5 to −10 11.6 8.60 8 low 5/95 0 80 flounder, sunflower sea star, lyre crab sunflower sea star, pink sea Jan 27 9 −10 to −20 16.2 13.5 10 low 5/95 0 3 star sunflower sea star, red rock Jan 27 10 −10 to −20 17.1 13.4 4 low 10/90 0 5 crab, big skate (egg case) sunflower sea star, striped Jan 28 11 −10 to −20 17.4 13.4 6 low 10/90 1 60 nudibranch Jan 29 12 −10 to −20 17.4 14.2 5 low 5/90 1 30 sunflower sea star

1 Converted maximum gauge depth (m) to chart datum (m). 2 Slope estimated over 4 m section perpendicular to transect (flat = less than 0.6 m difference in depth, low = 0.6 to 2.1 m difference in depth) 3 Other species observed: starry flounder (Platichthys stellatus); giant nudibranch (Dendronotus iris); lyre crab (Hyas lyratus); striped nudibranch (Armina californica); red rock crab (Cancer productus); longnose skate (Raja rhina); pink sea star (Pisaster brevispinus); sunflower sea star (Pycnopodia helianthoides); striped sun star (Solaster simpsoni); big skate eggcase (Raja binoculata); plumose anemone (Metridium farcimen)

Port Metro Vancouver APPENDIX B Hemmera RBT2 – Marine Benthic Subtidal Study - 4 - August 2014

Table B-4 Summary of YSI Instrument Measurements (temperature, salinity, and dissolved oxygen) at each Transect Location during the Gravid Female Crab (SCUBA) Survey

Depth Strata Salinity Dissolved O2 Depth Transect Tide Temperature (ºC) Dissolved O2 (%) Depth (m) (m) (psu) (mg/L) (m CD) 1 0 to −5 slack 7.3 28.46 8.50 84.8 −4.90 −2.00 2 0 to −5 flood 7.8 29.86 7.78 78.8 −5.50 −2.40 3 0 to −5 ebb 7.5 28.46 9.16 90.6 −6.70 −3.20 4 0 to −5 ebb 7.3 28.94 9.58 96.2 −6.10 −1.90 5 −5 to −10 ebb 7.6 26.03 8.17 80.0 −12.2 −9.10 6 −5 to −10 slack 7.2 28.32 8.33 83.3 −11.6 −7.80 7 −5 to −10 ebb 7.6 29.22 8.07 82.7 −14.0 −10.3 8 −5 to −10 ebb 7.8 29.70 8.49 86.0 −11.0 −8.30 9 −10 to −20 slack 7.8 29.77 8.43 86.0 −14.9 −12.2 10 −10 to −20 ebb 7.7 29.56 7.40 74.9 −16.8 −13.5 11 −10 to −20 ebb 7.6 29.34 8.20 83.5 −19.2 −15.3 12 −10 to −20 slack 7.7 29.49 7.49 76.2 −16.2 −13.0

Port Metro Vancouver APPENDIX B Hemmera RBT2 – Marine Benthic Subtidal Study - 5 - August 2014

Table B-5 Summary of Habitat Features and Dungeness Crab Data Collected at Every 10 m Quadrant Area (along each transect line) during the Gravid Female Crab (SCUBA) Survey

Location Substrate (%) Feature (%) Algae (% cover) No. of Crab Observed T Qu Mud Clay Sand SHHA SHWH WODE Bio Rip ALCL ALDR DETR Female Male Unknown 1 10 95 5 10 90 30 20 100 10 90 30 30 100 10 90 40 40 100 20 80 40 50 100 50 50 10 60 100 50 50 10 70 100 20 80 <5 80 100 20 80 10 90 100 <5 20 80 20 100 100 10 90 20 2 10 95 5 15 85 20 20 100 5 95 10 30 100 <5 10 90 20 40 100 100 40 50 100 100 40 60 100 100 30 70 100 20 80 30 80 100 10 90 40 90 100 10 90 40 100 100 100 30 Note: Location: T= Transect, Qu= Quadrat; Substrate: SHHA= shell hash, SHWH= shell whole, WODE= woody debris; Feature: Bio= bioturbation, Rip= ripple; Algae: ALCL= algae, clump, ALDR= Algae, drift, DETR= detritus.

Port Metro Vancouver APPENDIX B Hemmera RBT2 – Marine Benthic Subtidal Study - 6 - August 2014

Table B-5 continued

Location Substrate (%) Feature (%) Algae (% cover) No. of Crabs Observed T Qu Mud Clay Sand SHHA SHWH WODE Bio Rip ALCL ALDR DETR Female Male Unknown 3 10 95 5 100 20 95 5 100 30 95 5 100 5 40 95 5 100 50 95 5 100 60 95 5 100 70 95 5 10 90 80 75 5 20 5 95 5 90 95 5 5 95 100 95 5 30 70 4 10 <5 95 <5 5 95 10 20 <5 95 <5 100 5 30 <5 95 <5 100 5 40 <5 90 <5 <5 100 5 50 <5 95 <5 100 60 <5 95 <5 100 70 <5 95 <5 100 80 95 5 100 90 95 5 100 100 95 5 100

Port Metro Vancouver APPENDIX B Hemmera RBT2 – Marine Benthic Subtidal Study - 7 - August 2014

Table B-5 continued

Location Substrate (%) Feature (%) Algae (% cover) No. of Crabs Observed T Qu Mud Clay Sand SHHA SHWH WODE Bio Rip ALCL ALDR DETR Female Male Unknown 5 10 80 20 20 80 20 80 20 20 80 30 80 20 10 90 40 90 10 10 90 10 50 90 10 100 60 100 100 5 70 95 5 10 90 80 100 100 5 90 80 20 10 90 100 100 100 6 10 95 5 5 95 20 50 50 5 95 20 30 95 5 5 95 <5 40 5 95 15 85 <5 50 90 5 5 5 95 5 60 90 10 5 95 <5 1 70 90 10 5 95 80 90 10 5 95 90 95 5 5 95 100 95 5 5 95

Port Metro Vancouver APPENDIX B Hemmera RBT2 – Marine Benthic Subtidal Study - 8 - August 2014

Table B-5 continued

Location Substrate (%) Feature (%) Algae (% cover) No. of Crabs Observed T Qu Mud Clay Sand SHHA SHWH WODE Bio Rip ALCL ALDR DETR Female Male Unknown 7 10 NA NA 20 100 100 30 NA NA 40 100 5 95 1 1 50 NA NA 1 60 20 80 5 95 1 70 NA NA 80 20 80 5 95 90 NA NA 100 20 80 100 1 8 10 95 5 100 20 95 5 5 95 30 90 5 <5 100 1 40 95 <5 <5 100 1 50 <5 95 <5 100 60 95 5 100 70 95 5 100 80 95 5 5 95 <5 90 95 5 5 95 <5 100 95 5 100 1

Port Metro Vancouver APPENDIX B Hemmera RBT2 – Marine Benthic Subtidal Study - 9 - August 2014

Table B-5 continued

Location Substrate (%) Feature (%) Algae (% cover) No. of Crab Observed T Qu Mud Clay Sand SHHA SHWH WODE Bio Rip ALCL ALDR DETR Female Male Unknown 9 10 95 <5 <5 10 90 2 20 95 <5 <5 10 90 3 1 30 85 10 5 10 90 10 40 5 90 5 5 95 50 5 90 5 5 95 5 1 60 5 90 5 0 100 5 70 5 90 5 0 100 5 80 10 80 10 10 90 90 50 50 10 90 10 1 100 85 15 15 85 2 10 10 15 85 10 90 15 1 20 100 100 15 30 100 40 60 15 40 5 95 5 95 10 1 50 5 95 5 95 10 1 60 5 90 5 5 95 10 70 5 95 5 95 10 80 5 95 100 5 1 1 90 100 5 95 5 1 100 100 5 95

Port Metro Vancouver APPENDIX B Hemmera RBT2 – Marine Benthic Subtidal Study - 10 - August 2014

Table B-5 continued

Location Substrate (%) Feature(%) Algae (% cover) No. Crab Observed Female Male Unknown T Qu Mud Clay Sand SHHA SHWH WODE Bio Rip ALCL ALDR DETR 11 10 100 10 90 1 20 NA 1 1 30 NA 1 1 40 100 10 90 50 100 10 90 5 60 100 10 90 5 1 70 100 10 90 5 80 100 10 90 5 90 100 10 90 100 100 10 90 3 12 10 95 5 100 20 95 5 100 1 30 100 100 40 100 100 50 95 5 100 60 100 100 20 70 100 25 75 5 1 80 100 25 75 20 90 100 25 75 5 1 1 100 100 25 75

Port Metro Vancouver APPENDIX B Hemmera RBT2 – Marine Benthic Subtidal Study - 11 - August 2014

Table B-6 Summary of Remotely-Operated Vehicle Survey Transect Characteristics

Transect Depth Zone (m, Total Transect No. of Max Interval Min Interval Transect Survey Date Tidal State Speed CD) Length (m) Intervals Depth (m) Depth (m) (m/sec) 13 24/07/2013 Ebb −5 to −10 411 40 −10.4 −9.20 0.21 14 24/07/2013 Ebb −5 to −10 394 39 −9.9 −9.10 0.18 15 23/07/2013 Ebb −10 to −20 400 40 −19.5 −18.1 0.16 16-1 25/07/2013 Ebb −30 to −40 416 42 −40.2 −38.5 0.22 17 24/07/2013 Ebb −30 to −40 407 41 −36.6 −33.6 0.23

18 23/07/2013 Ebb −10 to −20 403 41 −13.6 −10.7 0.20 19 23/07/2013 Ebb −20 to −30 402 40 −30.1 −26.9 0.18 20 25/07/2013 Ebb −20 to −30 404 40 −30.4 −26.6 0.23 21-1 25/07/2013 Ebb −5 to −10 403 40 −9.10 −8.30 0.21

22 23/07/2013 Ebb/Flood −10 to −20 423 42 −13.4 −11.2 0.20 23 25/07/2013 Ebb −20 to −30 402 41 −27.5 −25.5 0.24 24 24/07/2013 Ebb −30 to −40 402 41 −41.3 −38.4 0.21

Average 406 41 −23.5 −21.0 0.20 SD 7.80 0.90 −12.3 −11.7 0.02

Port Metro Vancouver APPENDIX B Hemmera RBT2 – Marine Benthic Subtidal Study - 12 - August 2014

Table B-7 Summary of Remotely-Operated Vehicle Survey Transect Length (TL), Transect Width (TW) and Transect Area Surveyed (TA), After Correcting for ‘Off Bottom’ Events

2 Transect Transect Length (TL) (m) Transect Width (Tw) (m) Transect Area (TA) (m ) 13 399.9 0.57 227.1 14 382.4 0.50 192.7

15 395.8 0.58 229.5 16-1 416.0 0.73 304.5 17 407.0 0.76 309.7 18 399.3 0.64 256.8

19 392.4 0.57 222.9 20 404.0 0.77 309.5 21-1 396.3 0.73 290.9 22 416.7 0.67 277.1

23 402.0 0.84 338.5 24 405.0 0.72 292.4 Average 401.4 0.67 270.9 SD 9.570 0.10 44.56 Total 4817 8.09 3251

Port Metro Vancouver APPENDIX B Hemmera RBT2 – Marine Benthic Subtidal Study - 13 - August 2014

Table B-8 Summary of Crab (Dungeness and non-target) Data and Densities Collected during the Remotely-Operated Vehicle Survey

% No. of Density Density Density Density Density Transect No. of No. of No. of Intervals Crabs No. of D. of All of D. of Buried of NB D. of Other Transect Area Buried NB2 D. Other w/ D1. (All Crabs Crabs Crabs D. Crabs Crabs Crabs (T ) (m2) D. Crabs Crabs Crabs A Crabs species) (#/m2) (#/m2) (#/m2) (#/m2) (#/m2) 13 227.1 20 13 13 2 11 0 0.057 0.057 0.0088 0.048 0 14 192.7 8 5 3 1 2 2 0.026 0.016 0.0052 0.010 0.010 15 229.5 23 12 9 1 8 3 0.052 0.039 0.0044 0.035 0.013 16-1 304.5 7 6 3 0 3 3 0.020 0.001 0 0.0099 0.0099 17 309.7 32 17 15 0 15 2 0.055 0.048 0 0.048 0.0065 18 256.8 29 17 15 5 10 2 0.066 0.058 0.019 0.039 0.0078 19 222.9 3 8 1 0 1 7 0.036 0.0045 0 0.0045 0.031 20 309.5 28 16 12 5 7 4 0.052 0.039 0.016 0.023 0.013 21-1 290.9 13 6 5 2 3 1 0.021 0.017 0.0069 0.010 0.0034 22 277.1 26 19 14 2 12 5 0.069 0.051 0.0072 0.043 0.018 23 338.5 15 9 7 2 5 2 0.027 0.021 0.0059 0.015 0.0059 24 292.4 12 8 5 2 3 3 0.027 0.017 0.0068 0.010 0.010 Average 270.9 18 11 9 2 7 3 0.042 0.031 0.0067 0.025 0.011 SD 4455.8 10 5 5 2 5 2 0.018 0.019 0.0060 0.017 0.0080 Total 3251.6 n/a 136 102 22 80 34 n/a n/a n/a n/a n/a

1 Dungeness crab 2 Non-buried

Port Metro Vancouver APPENDIX B Hemmera RBT2 – Marine Benthic Subtidal Study - 14 - August 2014

Table B-9 Dungeness Size Calculations from the Remotely-Operated Vehicle Survey

Average Distance b/w Number of D.1 Average Carapace Width D. Crab Carapace Transect SD (cm) Lasers on Screen (L ) SD (cm) SD (cm) Crabs w/ Size on Screen (CW ) (cm) avg Width (CW) (cm) screen (cm) 13 2 3.8 2.6 7.1 0.1 10.6 7.6 15 2 4.8 1.1 6.6 0.8 14.4 1.5 17 2 3.8 0.2 4.8 0.2 15.8 1.6 18 3 3.0 0.5 4.3 0.7 14.1 0.3 20 2 3.9 0.9 5.2 1.6 15.1 1.2 21 1 n/a n/a n/a n/a n/a n/a 22 2 3.2 0.6 4.5 1.2 14.3 1.0

Table B-10 Summary of Habitat Features Data Collected during the Remotely-Operated Vehicle Survey

Total No. of No. of Intervals with Shell No. of Sea Pen Density No. of Crab No. of Intervals % of Intervals Transect Intervals Cover Sea Pens (#/m2) Traps w/ Algae w/ Algae

13 40 40 13 0.057 0 21 53 14 39 39 72 0.37 0 26 67 15 40 40 1 0.0044 0 35 88 16-1 42 2 18 0.059 0 6 14 17 41 41 4 0.013 0 16 39 18 41 41 11 0.043 0 31 76 19 40 40 4 0.018 0 34 85 20 40 40 0 0 0 12 30 21-1 40 40 536 1.8 3 40 100 22 42 42 511 1.8 1 33 79 23 41 41 86 0.25 0 18 44 24 41 41 2 0.0068 1 11 27 Average 41 37.3 105 0.38 0 24 58 SD 1.0 11.0 198 0.69 1 11 28 Total 487 447 1258 4.5 5 283 n/a

1 Dungeness crab

Port Metro Vancouver APPENDIX B Hemmera RBT2 – Marine Benthic Subtidal Study - 15 - August 2014

Table B-11 Summary of Invertebrate and Finfish Species Identified during the Remotely-Operated Vehicle Survey

Species Transect Species (or higher taxa) 13 14 15 16-1 17 18 19 20 21-1 22 23 24 Total Count (Common Name) Latin Name Invertebrate Presence and Count Dungeness crab Metacarcinus magister 13 3 9 3 15 15 1 12 5 14 7 5 102 Graceful decorator crab Oregonia gracilis 2 1 1 5 2 3 2 2 18 Tanner crab Chionoecetes bairdi 1 2 2 1 6 Red rock crab Cancer productus 2 1 3 Northern kelp crab Pugettia productus 1 1 Unknown crab sp. n/a 2 1 1 1 5 Orange sea pen Ptilosarcus gurneyi 13 72 1 18 4 11 4 0 536 511 86 2 1,258 Anemone sp. Actiniaria (order) 1 1 Pycnopodia Sunflower seastar 2 1 3 helianthoides Seastar sp. Asteroidea (class) 1 1

Port Metro Vancouver APPENDIX B Hemmera RBT2 – Marine Benthic Subtidal Study - 16 - August 2014

Species Transect Species (or higher taxa) 13 14 15 16-1 17 18 19 20 21-1 22 23 24 Total Count (Common Name) Latin Name Invertebrate Presence and Count Finfish Presence and Count Pleuronectiformes Flatfish sp. 29 31 53 14 26 60 44 18 28 31 29 36 399 (order) Pacific snake Lumpenus sagitta 2 3 1 2 7 2 5 24 1 5 6 58 prickleback Pacific sanddab Citharichthys sordidus 6 2 1 6 2 17 Spiny dogfish Squalus suckleyi PT1 PT PT PT PT PT PT PT PT n/a Unknown bony fish sp. n/a 4 3 1 1 8 6 3 5 1 2 2 2 38 Cottoidae Sculpin sp. 3 1 1 3 8 11 4 15 1 4 4 1 56 (superfamily) Skate sp. (egg case) Raja (genus) 1 1 2 6 10 Poacher sp. Agonidae (family) 1 3 2 5 6 1 3 7 13 41 Dover sole Microstomus pacificus 1 1 2 4 Eelpout sp. Zoarcidae (family) 2 1 1 4 Glyptocephalus Rex sole 1 1 zachirus Rock sole Lepidopsetta bilineata 1 1 Hemilepidotus Brown Irish Lord 1 1 spinosus Goby sp. Gobiidae (family) 1 1 Codfish sp. Gadidae (family) 1 4 5 Plainfin midshipman Porichthys notatus 1 1 Invertebrates 26 77 13 24 21 30 12 16 542 532 95 10 1,398 Minimum Number Finfish 38 36 63 29 54 88 63 50 54 41 58 63 637 Observed Total 64 113 76 53 75 118 75 66 596 573 153 73 2,035

1 PT=Present Throughout

Port Metro Vancouver APPENDIX B Hemmera RBT2 – Marine Benthic Subtidal Study - 17 - August 2014

Table B-12 Summary of Finfish (flatfish and non-target finfish) Data and Densities Collected during the Remotely-Operated Vehicle Survey

No. of Density Density Density of Density Density Transect % of No. of No. of No. of Fish No. of 1 of All of Buried of NB of Other Transect Area (TA) Intervals Buried NB Other 2 (All Flatfish Flatfish Flatfish Flatfish Flatfish Fish (m ) w/ Fish Flatfish Flatfish Fish 2 2 2 2 2 Species) (#/m ) (#/m ) (#/m ) (#/m ) (#/m ) 13 227.11 55 38 29 1 28 9 0.17 0.13 0.0044 0.12 0.040 14 192.72 72 36 31 6 25 5 0.19 0.16 0.031 0.13 0.026 15 229.54 80 62 54 5 49 8 0.27 0.24 0.022 0.21 0.035 16-1 304.51 52 29 20 3 17 9 0.095 0.07 0.0098 0.056 0.030 17 309.73 71 53 29 4 25 24 0.17 0.094 0.013 0.081 0.077 18 256.75 88 88 62 7 55 26 0.34 0.24 0.027 0.21 0.10 19 222.87 85 61 44 7 37 17 0.27 0.20 0.031 0.17 0.076 20 309.46 70 50 24 5 19 26 0.16 0.078 0.016 0.061 0.084 21-1 290.88 50 54 28 2 26 26 0.19 0.096 0.0069 0.089 0.089 22 277.11 55 41 31 1 30 10 0.15 0.11 0.0036 0.11 0.036 23 338.48 68 52 34 6 28 18 0.15 0.10 0.018 0.083 0.053 24 292.41 76 63 36 1 35 27 0.22 0.12 0.0034 0.12 0.092 Average 27096.6 68 52 35 4 31 17 0.20 0.14 0.016 0.12 0.062 SD 4455.8 13 16 12 2 11 9 0.068 0.060 0.010 0.053 0.028 Total 325158.9 n/a 627 422 48 374 205 n/a n/a n/a n/a n/a

1 Non-Buried

Port Metro Vancouver APPENDIX B Hemmera RBT2 – Marine Benthic Subtidal Study - 18 - August 2014

Table B-13 Flatfish Size Calculations from the Remotely-Operated Vehicle Survey

Average Distance Number of Average Length on Screen Transect SD (cm) between Lasers on SD (cm) Fish Length (TL) (cm) SD (cm) Flatfish w/ Size (TLscreen) (cm) Screen (Lavg) (cm) 15 3 5.5 0.5 6.5 0.5 17.1 2.0 16 3 4.8 1.3 5.5 1.7 19.2 8.3 17 2 4.3 0.1 5.4 0.1 15.7 0.7 19 3 4.3 1.0 7.2 1.1 12.1 2.2 20 3 5.0 1.2 6.2 0.6 16.1 4.6 21 9 3.1 0.5 4.9 0.7 12.7 1.4 22 2 2.4 0.2 4.4 0.4 10.8 0.1 23 3 4.7 1.0 5.3 0.6 17.7 1.8 24 6 3.5 0.8 6.2 1.3 12.0 4.2

Port Metro Vancouver APPENDIX B Hemmera RBT2 – Marine Benthic Subtidal Study - 19 - August 2014

Table B-14 Two Factor ANOVA Test Criterion for the Effects of Sediment Grain Size and Depth on the Species Treatments

Species Treatments df Sum of Squares F P Depth 3 0.403 5.448 0.001* Total Dungeness crab density Sediment grain size 3 0.143 1.938 0.123 Depth x sediment grain size 9 0.563 2.538 0.008* Depth 3 0.066 3.310 0.020* Dungeness crab density (buried) Sediment grain size 3 0.018 0.912 0.435 Depth x sediment grain size 9 0.095 1.576 0.119 Depth 3 0.197 3.260 0.021* Dungeness crab density (non-buried) Sediment grain size 3 0.054 0.898 0.442 Depth x sediment grain size 9 0.454 2.507 0.008 Depth 3 0.396 4.196 0.006* Total crab density Sediment grain size 3 0.268 2.844 0.037* (all crab species) Depth x sediment grain size 9 0.479 1.692 0.088 Depth 3 12.842 23.352 <0.001* Orange sea pen density Sediment grain size 3 11.959 21.746 <0.001* Depth x sediment grain size 9 11.359 6.885 <0.001* Depth 3 0.139 0.458 0.712 Total flatfish density Sediment grain size 3 0.114 0.373 0.772 (all flatfish species) Depth x sediment grain size 9 2.751 3.004 0.002* Depth 3 0.058 0.827 0.479 Flatfish density (buried) Sediment grain size 3 0.038 0.545 0.652 Depth x sediment grain size 9 0.194 0.917 0.509 Depth 3 0.041 0.140 0.936 Flatfish density Sediment grain size 3 0.155 0.530 0.662 (non-buried) Depth x sediment grain size 9 2.128 2.431 0.011* Depth 3 1.057 3.134 0.025* Total finfish density Sediment grain size 3 0.039 0.115 0.952 (all species) Depth x sediment grain size 9 4.594 4.543 <0.001* Note: * denotes statistically significant results at α≤0.05

Port Metro Vancouver APPENDIX B Hemmera RBT2 – Marine Benthic Subtidal Study - 20 - August 2014

Table B-15 Test Criterion for (A) ANOVA along Delta-front Slope Location, and (B) Inside and Outside of the Proposed Dredge Zone, and (C) Linear Regression of Sea Pen Density, on the Species Treatments

(A) 1-ANOVA of Along Delta front slope Location (C) Linear Regression Sea pen Density Species Treatments df Sum of Squares F P R2 P Total Dungeness crab density 2 0.14 2.80 0.06 0.0001 0.81 Buried Dungeness crab density 2 0.03 2.06 0.13 0.001 0.57 Non-buried Dungeness crab density 2 0.07 1.76 0.17 0.00002 0.93 Total crab density (all species) 2 0.10 1.57 0.21 0.00002 0.93 Orange sea pen density 2 40.31 104.93 <.0001* Total flatfish density 2 0.18 0.82 0.44 0.004 0.18 Buried flatfish density 2 0.01 0.19 0.82 0.002 0.38 Non-buried flatfish density 2 0.21 1.01 0.37 0.003 0.27 Total finfish density (all species) 2 0.83 3.22 0.04* 0.01 0.02* (B) 1-ANOVA of Inside and Outside the proposed Dredge Zone (DZ) Total Dungeness crab density 1 0.035 6.041 0.014* Buried Dungeness crab density 1 0.002 1.673 0.196 Non-buried Dungeness crab density 1 0.021 4.481 0.035* Total crab density (all species) 1 0.016 2.091 0.149 Orange sea pen density 1 48.965 69.11 <0.0001* Total flatfish density 1 0.561 3.105 0.079 Buried flatfish density 1 0.067 3.602 0.058 Non-buried flatfish density 1 0.241 1.632 0.202 Total finfish density (all species) 1 2.717 9.481 0.002*

APPENDIX C Photographs

Port Metro Vancouver APPENDIX C Hemmera RBT2 – Marine Benthic Subtidal Study - 1 - August 2014

Photo C-1 The Seaeye Falcon© 12127 ROV on deck prior to deployment.

Photo C-2 The Seaeye Falcon© 12127 ROV being deployed using a hydraulic marine winch system.

Port Metro Vancouver APPENDIX C Hemmera RBT2 – Marine Benthic Subtidal Study - 2 - August 2014

Photo C-3 The Seaeye Falcon© 12127 ROV immediately after deployment prior to decent (left) and at the surface and returning to the boat immediately after surfacing post-transect (right).

Photo C-4 Dungeness crab (Metacarcinus magister) with laser size-indicators, Transect 17. The substrate was classified as sand; the dominant substrate cover was shell hash; and substrate complexity was low.

Port Metro Vancouver APPENDIX C Hemmera RBT2 – Marine Benthic Subtidal Study - 3 - August 2014

A)

B)

C)

D)

Photo C-5 Along transect 20, a small demersal fish and a Dungeness crab (Metacarcinus magister): A) buried in the sediment; B) starting to unbury from the sediment; C) partially unburied from the sediment and almost fully visible; and D) completely unburied and retreating from the ROV. The substrate was classified as sand; the dominant substrate cover was shell hash; and the complexity was low.

Port Metro Vancouver APPENDIX C Hemmera RBT2 – Marine Benthic Subtidal Study - 4 - August 2014

Photo C-6 An orange sea pen (Ptilosarcus gurneyi) in good visibility along Transect 14. The substrate was classified as sand; the dominant substrate cover was shell hash; and the substrate complexity was low.

Photo C-7 Orange sea pens (Ptilosarcus gurneyi) in poor visibility along Transect 22. The substrate was classified as sand; the dominant substrate cover was shell hash; and the substrate complexity was low.

Port Metro Vancouver APPENDIX C Hemmera RBT2 – Marine Benthic Subtidal Study - 5 - August 2014

Photo C-8 A swimming anemone (Stomphia didemon) along Transect 17. The substrate was classified as sand; the dominant substrate cover was shell hash; and the substrate complexity was medium.

Photo C-9 A flatfish close-up, Transect 23. The substrate was classified as sand; the dominant substrate cover was shell hash; and substrate complexity was low.

Port Metro Vancouver APPENDIX C Hemmera RBT2 – Marine Benthic Subtidal Study - 6 - August 2014

Photo C-10 A flatfish, Transect 23, with laser size-indicators visible on the substrate surface. The substrate was classified as sand; the dominant substrate cover was shell hash; and substrate complexity was low.

Photo C-11 Multiple flatfish, Transect 17, in relatively poor visibility. The substrate was classified as sand; the dominant substrate cover was shell hash; and substrate complexity was low.

Port Metro Vancouver APPENDIX C Hemmera RBT2 – Marine Benthic Subtidal Study - 7 - August 2014

Photo C-12 Big skate (Raja binoculata) egg case along Transect 23. The substrate was classified as sand; and dominant substrate cover was shell hash; and substrate complexity was low.

Photo C-13 An orange sea pen (Ptilosarcus gurneyi), a Dungeness crab (Metacarcinus magister), and a spiny dogfish (Squalus suckleyi), Transect 18. The substrate was classified as sand; the dominant substrate cover was shell hash; and the substrate complexity was low.

Port Metro Vancouver APPENDIX C Hemmera RBT2 – Marine Benthic Subtidal Study - 8 - August 2014

Photo C-14 The Van Veen© grab used to collect subtidal sediment samples from the study area.

Photo C-15 Van Veen© grab from Roberts Bank, depth zone −10 to −20 m, site 15S, showing a predominantly sand substrate.

APPENDIX D Supplementary Information

Port Metro Vancouver APPENDIX D Hemmera RBT2 – Marine Benthic Subtidal Study - 1 - August 2014

APPENDIX D: GEOSPATIAL INTERPOLATIONS – INVERSE DISTANCE WEIGHTING (IDW)

Background

Spatial interpolations, which help with spatial pattern analysis, were completed for the Habitat Suitability Modelling TR (Hemmera 2014cHemmera 2014c) using an Inverse Distance Weighting (IDW) method. ESRI defines IDW as follows:

‘An interpolation technique that estimates cell values in a raster from a set of sample points that have been weighted so that the farther a sampled point is from the cell being evaluated, the less weight it has in the calculation of the cell's value’ (ESRI 2014)

There are often good arguments for the use of more sophisticated geospatial interpolation methods, including Kriging; however, such techniques are generally more reliant on assumptions about the underlying data (including for example, the data distribution). Such techniques, therefore, require greater user expertise and prior analysis of the data characteristics (ESRI 2014).

When undertaking IDW interpolations in ArcGIS, Surfer or similar software, there are typically two options available for defining the actual data points used in determining an interpolated value (within a raster, or at each grid vertex): (i) fixed search radius; and (ii) variable search radius (also described as nearest neighbor approach). IDW interpolations for the Habitat Suitability Modelling TR (Hemmera 2014c) were completed using a variable radius approach, since this better accommodates data sets with uneven spatial coverage and provides outputs that are less prone to representation as concentric circles, which are an artefact of the search algorithm (ESRI 2014).

For the Habitat Suitability Modelling TR (Hemmera 2014cHemmera 2014c), IDW parameter settings using ArcGIS 10.2.1 IDW Spatial Analyst tool were:

1) Grid Size – 20 m; 2) Variable search radius – 500 m; 3) Maximum Sample Points – 12; and 4) Power – 2.

Search radius defines which of the input points are used to interpolate the value for each cell in the output raster, and with a variable search radius, the number of points used in calculating the value of the interpolated cell is specified (i.e., maximum sample points). This makes the radius distance vary for each interpolated cell depending on how far the specified input points are from each interpolated cell. In other words, the density of sample locations near each interpolated cell affects the size of each ‘neighborhood’ with some being small (in areas with high sampling density) and others large (in areas with lower sampling density) (ESRI 2014).

Port Metro Vancouver APPENDIX D Hemmera RBT2 – Marine Benthic Subtidal Study - 2 - August 2014

Power is the exponent of distance, and this parameter controls the significance of surrounding points on the interpolated value. A higher power results in less influence from distant points, and a lower power results in a greater influence from distant points. The power value can be any real number greater than 0, but the most reasonable results will be obtained using values from 0.5 to 3. The default is two (ESRI 2014).

Assumptions and Limitations

The key assumption of IDW is that the variable being mapped decreases in influence with distance from its sampled location (ESRI 2014).

Generally, when undertaking IDW interpolations, the power assigned will determine the extent to which closer versus more distant values influence the interpolated value. According to ESRI:

‘IDW relies mainly on the inverse of the distance raised to a mathematical power. The Power parameter lets you control the significance of known points on the interpolated values based on their distance from the output point. It is a positive, real number, and its default value is two. By defining a higher power value, more emphasis can be put on the nearest points. Thus, nearby data will have the most influence, and the surface will have more detail (be less smooth). As the power increases, the interpolated values begin to approach the value of the nearest sample point. Specifying a lower value for power will give more influence to surrounding points that are farther away, resulting in a smoother surface’ (http://resources.arcgis.com/en/help/main/10.2/index.html#/How_IDW_works/009z00000075000000/. ESRI 2014).

For RBT2 surveys, a power of two provides an appropriate level of smoothing for tidal flats commensurate with spatial variation over hundreds of metres, and for a study area that extends seaward and parallel to the shore for > 3 to 5 km. Except in those circumstances where there is a need to understand spatial variation over much small scales (< 100 m), powers higher than 2 should be avoided (ESRI 2014).