Deep-Sea Coral Research and Technology 

Program: Alaska Deep-Sea Coral and 

Sponge Initiative Final Report

Chris Rooper, Robert Stone, Peter Etnoyer, Christina Conrath, 

Jennifer Reynolds, H. Gary Greene, Branwen Williams, Enrique 

Salgado, Cheryl Morrison, Rhian Waller, and Amanda Demopoulos

U.S. Department of Commerce 

National Oceanic and Atmospheric Administration 

National Marine Fisheries Service 

NOAA Technical Memorandum NMFS-OHC-2 

June 2017 

 

Deep-Sea Coral Research and Technology Program: 

Alaska Deep-Sea Coral and Sponge Initiative Final Report 

Chris Rooper1, Robert Stone2, Peter Etnoyer3, Christina Conrath4, Jennifer Reynolds5, 

H. Gary Greene6

, Branwen Williams7, Enrique Salgado3, Cheryl Morrison8, Rhian Waller9, 

and Amanda Demopoulos10

1 NOAA, National Marine Fisheries Service, Alaska Fisheries Science Center, 7600 Sand Point Way, NE, 

Bldg. 4, Seattle, WA 98115 

2 NOAA, National Marine Fisheries Service, Alaska Fisheries Science Center, 17109 Pt Lena Loop Road, 

Juneau, AK 99801 

3 NOAA, National Ocean Service, National Centers for Coastal Ocean Science, 219 Fort Johnson Rd., 

Charleston, SC 29412 

4 NOAA, National Marine Fisheries Service, Alaska Fisheries Science Center, 301 Research Court, 

Kodiak, AK 99615-7400 

5 College of Fisheries and Ocean Sciences, University of Alaska, Fairbanks, AK 99775 

6 Moss Landing Marine Laboratories, 8272 Moss Landing Road, Moss Landing, CA 95039 

7 W.M. Keck Science Department of Claremont McKenna College, Pitzer College, and Scripps College, 

Claremont, CA 91711 

8

USGS, Leetown Science Center, 11649 Leetown Road, Kearneysville, WV 25430 

9

University of Maine, Darling Marine Center, 193 Clarks Cove Road, Walpole, ME 04573 

10USGS, Wetland and Aquatic Research Center, 7920 NW 71st Street, Gainesville, FL 32653 

NOAA Technical Memorandum NMFS-OHC-2 

June 2017

U.S. Department of Commerce 

Wilbur L. Ross, Jr., Secretary 

National Oceanic and Atmospheric Administration 

Benjamin Friedman, Acting NOAA Administrator 

National Marine Fisheries Service 

Chris Oliver, Assistant Administrator for Fisheries 
ii

Recommended citation:

Rooper, C., R. Stone, P. Etnoyer, C. Conrath, J. Reynolds, H.G. Greene, B. Williams, E. 

Salgado, C. Morrison, R. Waller, and A. Demopoulos. 2017. Deep-Sea Coral Research and 

Technology Program: Alaska Deep-Sea Coral and Sponge Initiative Final Report. NOAA Tech. 

Memo. NMFS-OHC-2, 65 p. 

Copies of this report may be obtained from: 

Heather Coleman 

NMFS Office of Habitat Conservation

National Oceanic and Atmospheric Administration 

1315 East-West Highway, Room 14201 

Silver Spring, MD 20910 

Or online at:

http://spo.nmfs.noaa.gov/tm/ or http://deepseacoraldata.noaa.gov/library 
iii

Table of Contents

List of Figures .......................................................................................................................................iv

Executive Summary.............................................................................................................................vii

Acknowledgments................................................................................................................................. x

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

2. Major Field Research Projects........................................................................................................... 2

2.1 Red tree coral (Primnoa pacifica) thicket habitats in the eastern Gulf of Alaska ...................... 4

2.2. Mapping and modeling coral and sponge distribution in the Aleutian Islands...................... 11

2.3 Productivity of FMP species in coral and sponge habitats in the Alaska region......................13

3. Associated studies ............................................................................................................................17

3.1. Recruitment of red tree coral (Primnoa pacifica) in thicket habitats in the eastern Gulf of 

Alaska ................................................................................................................................................17

3.2 Reproductive ecology of red tree coral (Primnoa pacifica) in thicket habitats in the eastern 

Gulf of Alaska....................................................................................................................................21

3.3 Food-web ecology and trophic ecology of red tree corals (Primnoa pacifica) in the eastern 

Gulf of Alaska................................................................................................................................... 22

3.4. Geological substrate mapping and bathymetry and sediment compilations......................... 25

3.5. Recovery, ages and growth rates of Primnoa pacifica in the Gulf of Alaska ........................... 30

3.6. Distribution models for eastern Bering Sea, Gulf of Alaska and Aleutian Islands deep-sea 

coral and sponge.............................................................................................................................. 37

3.7. Longline Impacts study............................................................................................................. 39

3.8. Genetic connectivity among offshore and emergent fjord-populations of red tree corals 

(Primnoa pacifica) in the Gulf of Alaska.........................................................................................42

3.9. Long-term monitoring of O2 and pH in Alaska waters; a sentinel for global climate change 

and ocean acidification....................................................................................................................46

3.10. Long-term monitoring of oceanographic conditions in Southeast Alaska ...........................48

3.11. Taxonomy of Alaska sponges and corals .................................................................................50

3.12. Marine natural products studies of Alaskan sponge fauna .................................................... 52

4. Conclusions ..................................................................................................................................... 55

5. Suggestions for future implementation/administration................................................................ 57

6. Priorities for future research...........................................................................................................58

7. References........................................................................................................................................59

8. Appendices .......................................................................................................................................61

8.1. Budget expenditures...................................................................................................................61

8.2. Publications to date ..................................................................................................................63

8.3. Electronic resources:.................................................................................................................65
iv

List of Figures

Figure 1. Locations of research cruises funded in FY12-15 by the Deep-Sea Coral Research and 

Technology Program. The Aleutian Islands mapping project was conducted in the area 

outlined by the red border, the fish productivity project was conducted at the two sites 

indicated by orange circles, and the Alaska Primnoa study was conducted at the four of 

the five sites (Cape Ommaney, Prince of Wales, Dixon Entrance and Fairweather Ground) 

in the eastern Gulf of Alaska indicated by green circles. ........................................................ 2

Figure 2. Map of Alaska showing the six study sites. Sites 1–5 (Dixon Entrance, Prince of Wales, 

Shutter Ridge, Fairweather Ground and Edgecumbe Pinnacle) were surveyed with 

remotely operated vehicles in the eastern Gulf of Alaska in 2013 and 2015. Site 6 (Chirikof) 

was not surveyed using remotely operated vehicles. .............................................................. 8

Figure 3. The ROV Zeus II, used during the 2015 expedition, is recovered after a dive at the 

Fairweather Ground (Site 4) where it collected a large red tree coral colony for age and 

paleo-climatological analyses................................................................................................... 9

Figure 4. A large rougheye rockfish (Sebastes aleutianus) in a red tree coral colony at a depth of 

347 m in the Dixon Entrance basin (Site 1). The coral is attached to a large glacial dropstone and is being preyed upon by calliostomatid snails (Otukaia sp.)................................. 9

Figure 5. Longline damage to a large red tree coral at a depth of 193 m at the Shutter Ridge (Site 

3). ..............................................................................................................................................10

Figure 6. Redbanded rockfish (Sebastes babcocki) are common residents in red tree coral thickets, 

this one at 207 m at the Shutter Ridge (Site 3). The large glass sponge (Farrea occa) is also 

common in red tree coral thickets and grow to more than 3 m in diameter........................10

Figure 7. Densities of various benthic invertebrates from the towed camera fieldwork conducted 

in the Aleutian Islands in 2012 and 2014. ................................................................................12

Figure 8. Mean height (and standard error) of coral and sponge observed in the Aleutian Islands.

..................................................................................................................................................13

Figure 9. Example images from the Aleutian Islands. ........................................................................13

Figure 10. Location of study sites for FMP production study in the Gulf of Alaska. .........................14

Figure 11. Preliminary reproductive productivity of northern and dusky rockfish during the month 

of May 2014, measured as a) gonadosomatic index, b) relative fecundity, and c) 

reproductive failure, separated by habitat and site. 49 FP = the 49 Fathom Pinnacle site, 

and SHB = the Snakehead Bank site. ......................................................................................16

Figure 12. Retrieval of array # 8 at Site 4 (Fairweather Ground) at a depth of 140 m........................19

Figure 13. Retrieval of array # 8 at Site 4 (Fairweather Ground) showing heavy growth of hydroids 

after a 22-month deployment.................................................................................................. 19

Figure 14. Re-deployment of array #5 at Site # 4 (Fairweather Ground) at a depth of 143 m. .........20

Figure 15. A new recruit (2-polyp stage) Calcigorgia spiculifera collected on one of the settling 

arrays at Site 3 (Shutter Ridge) in June 2015. .........................................................................20

Figure 16. Relationship of δ13N and δ13C raw data (A) and average values (B) for red tree corals 

collected at Site 3 (Shutter Ridge) in the eastern Gulf of Alaska in 2013 and the particulate 

organic matter (POM) collected at the same collection sites. O1-O4 are coral tissue 

samples and POM01-POM03 are the POM samples. The estimated trophic level arrow 

indicates that all coral samples are approximately 1.5 to 3 trophic levels above the 

measured POM. ......................................................................................................................24
v 

Figure 17. Multibeam bathymetric images of the Chirikof dive site selected for ROV examination 

and sampling of deep-water corals and sponges. Red outlines indicate interesting 

geological features identified for further exploration with underwater cameras or remote 

operated vehicles. ................................................................................................................... 27

Figure 18. Multibeam bathymetric images of the Fairweather Ground dive site selected for ROV 

examination and sampling of deep-water corals and sponges. Red outlines indicate 

interesting geological features identified for further exploration with underwater cameras 

or remote operated vehicles................................................................................................... 27

Figure 19. Marine benthic habitat map of the Cape Ommaney dive site selected for ROV 

examination and sampling of deep-water corals and sponges. ............................................28

Figure 20. Multibeam bathymetric images of the Prince of Wales dive site selected for ROV 

examination and sampling of deep-water corals and sponges. Red outlines indicate 

interesting geological features identified for further exploration with underwater cameras 

or remote operated vehicles...................................................................................................29

Figure 21. Multibeam bathymetric images of the Dixon Entrance dive site selected for ROV 

examination and sampling of deep-water corals and sponges. Red outlines indicate 

interesting geological features identified for further exploration with underwater cameras 

or remote operated vehicles...................................................................................................29

Figure 22. Depth-profile of Shutter Ridge (top, from NNE to SSW), plan view (inset left, red is 

shallow), and perspective view (bottom, yellow is shallow)................................................. 32

Figure 23. In situ stereo images showing the method for estimating Primnoa pacifica colony sizes 

using Sebastes 1.3 software (Williams et al. 2016). Euclidean triangulation is used to 

estimate distance based on the comparison between six measured values in two calibrated 

cameras mounted on a sled.................................................................................................... 32

Figure 24. Size distribution (m size categories) of observed Primnoa pacifica colonies in Shutter 

Ridge. A total of 1,020 colonies were measured.................................................................... 34

Figure 25. Distribution of Primnoa pacifica colony sizes. Black triangles represent survey tracks. 

The largest Primnoa pacifica colonies were generally observed in the deep rocky portion of 

the Shutter Ridge. They were absent from areas shallower than 100 m............................... 35

Figure 26. Radiocarbon results for three Primnoa pacifica colonies. Δ14C values were measured 

across a basal cross-section (top) and a linear transect (bottom) for each specimen. ........ 36

Figure 27. Predicted probability of presence or absence of coral, sponges and sea whips and sea 

pens from a generalized additive model (Sigler et al. 2015).................................................. 38

Figure 28. Predictions of the best-fitting generalized additive model for sponge, coral, 

Primnoidae, and Stylasteridae predicting the abundance (log-transformed catch-per-unitof-effort (CPUE) or CPUE) in the Aleutian Islands (left) and pennatulaceans, corals and 

sponges in the Gulf of Alaska (right) bottom trawl surveys (Rooper et al. 2014, Rooper et 

al. in review)............................................................................................................................ 39

Figure 29. Example accelerometer data (acceleration, velocity, and distance in x, y and z 

directions) for two deployments on longline gear. The left hand deployment shows a 

probable movement of the longline gear during the middle of the deployment, while the 

right hand deployment shows a stationary deployment........................................................41

Figure 30. Map of the eastern Gulf of Alaska showing the five study sites (Site 1, Site 3, Site 4, 

Tracy Arm and Endicott Arm) where samples were collected from red tree corals to study 

genetic connectivity in 2013 and 2015.....................................................................................44

Figure 31. Collecting red tree coral samples for genetics studies with the ROV Zeus II at Site 4 

(Fairweather Ground) in June 2015. .......................................................................................45
vi

Figure 32. Maps of summer distribution of seafloor O2 (left panel) and pH (right panel) during 

trawl surveys of eastern Bering Sea slope (2012), Gulf of Alaska (2013), and Aleutian Islands 

(2014). ......................................................................................................................................47

Figure 33. Scuba divers deploy an oceanographic array in a red tree coral (Primnoa pacifica) 

thicket in Tracy Arm, Holkham Bay, Southeast Alaska. .......................................................49

Figure 34. Hamancantha (Vomerula) cassanoi discovered at a depth of 174 at Site 4 (Fairweather 

Ground) during the 2015 eastern Gulf of Alaska expedition................................................. 52

Figure 35. The demosponge Latrunculia austini at a depth of 94 meters at Site 3 (Shutter Ridge).54

Figure 36. The demosponge Suberites montalbidus, also known as the “stinky sponge”, is very 

abundant in some areas of the southern Bering Sea. Pictured here is the catch of the stinky 

sponge from a bottom trawl survey haul in the eastern Bering Sea..................................... 54

Figure 37.Proportion of expenditures by funding source ($3.17 million for FY12-15 combined) 

during the lifetime of the Alaska Coral and Sponge Initiative. ............................................ 58
vii

Executive Summary

Deep-sea coral and sponge ecosystems are widespread throughout most of Alaska’s marine 

waters. In some places, such as the central and western Aleutian Islands, deep-sea coral and 

sponge resources can be extremely diverse and may rank among the most abundant deep-sea 

coral and sponge communities in the world. Many different species of fishes and invertebrates are 

associated with deep-sea coral and sponge communities in Alaska. Because of their biology, these 

benthic invertebrates are potentially impacted by climate change and ocean acidification. Deepsea coral and sponge ecosystems are also vulnerable to the effects of commercial fishing activities. 

Because of the size and scope of Alaska’s continental shelf and slope, the vast majority of the area 

has not been visually surveyed for deep-sea corals and sponges. NOAA’s Deep Sea Coral Research 

and Technology Program (DSCRTP) sponsored a field research program in the Alaska region

between 2012–2015, referred to hereafter as the Alaska Initiative. The priorities for Alaska were 

derived from ongoing data needs and objectives identified by the DSCRTP, the North Pacific 

Fishery Management Council (NPFMC), and Essential Fish Habitat-Environmental Impact 

Statement (EFH-EIS) process. 

This report presents the results of 15 projects conducted using DSCRTP funds from 2012-2015. 

Three of the projects conducted as part of the Alaska deep-sea coral and sponge initiative 

included dedicated at-sea cruises and fieldwork spread across multiple years. These projects were 

the eastern Gulf of Alaska Primnoa pacifica study, the Aleutian Islands mapping study, and the 

Gulf of Alaska fish productivity study. In all, there were nine separate research cruises carried out

with a total of 109 at-sea days conducting research. The remaining projects either used data and 

samples collected by the three major fieldwork projects or were piggy-backed onto existing 

research programs at the Alaska Fisheries Science Center (AFSC).

The suite of projects that examined P. pacifica habitats and associated species in the eastern Gulf 

of Alaska were important and provided significant new information about these communities. 

The multibeam mapping project extended coverage in the region by an additional ~167 square 

nautical miles to depths of 1300 m in areas of known or suspected P. pacifica habitat. The study 

confirmed that P. pacifica habitat extends significantly beyond the areas currently closed to 

fishing as part of the Habitat Areas of Particular Concern (HAPCs) in the region. At a number of 

the unprotected sites there was evidence of damage to P. pacifica from longline fishing activity. 

Colony sizes were related to depth, with the largest colonies exceeding 2 m in height and found at 

the deeper depths (> 200 m). These large colonies (> 2 m) also formed a significant portion of the 

population, comprising 10% of the total colonies. Overall, almost 70% of the colonies were > 1 m 

in height and the recovery time for the largest colonies was estimated at > 100 years and 50-60 

years for the average size colonies. The samples collected during this study using a remotely 

operated vehicle (ROV) were used to examine reproductive ecology, feeding ecology, and genetic 

connectivity of P. pacifica. As a group, these studies confirmed the gonochorism and multiple 

developing cohorts of oocytes that have been previously observed in shallow-water populations. 

However, the study also found evidence for reduced fecundity in the deeper water populations. 

Recruitment substrates were also deployed in the P. pacifica thickets and the absence of new P. 

pacifica recruits after 22 months confirmed the episodic and rare nature of successful recruitment 

for this species. However, the observed recruitment of another octocoral (Calcigorgia spiculifera) 

was unique and indicated the potential for the success of the experimental design. The settlement 

plates were redeployed for future retrieval. The feeding ecology study indicated that P. pacifica is 
viii

likely feeding on both particulate organic matter (POM) and zooplankton, findings similar for 

other species in other regions of the deep-sea. 

An important accomplishment of the Alaska Initiative was the production of maps of predicted 

occurrence of corals and sponges on a 1 ha scale for each of the three major regions of Alaska. 

These maps and models were confirmed (with the exception of the wider Gulf of Alaska) with 

field studies and indicated that coral and sponge ecosystems occur at predictable locations where 

hard bottom substrate is present. During the course of the project three previously unexplored 

locations were also examined using field observations, Bowers Bank and Ridge and the eastern 

and western Aleutian Islands. These explorations found that dense coral and sponge communities 

are found throughout the western Aleutians, on the shallowest depths of Bowers Bank, and in the 

area from Sequam Pass to Unalaska Island. Areas without coral and sponge communities were 

also identified, especially on the shelf south of Unalaska Island, in the deeper areas of Bowers 

Ridge, and between Aggatu and Attu Islands. One of the important variables to come out of this 

modeling was the effect of current speed (either tidal currents or mean oceanographic currents) 

on the distribution of corals and sponges. The highest densities tended to be in areas where 

currents could be moderate to high (> 50 cm/s). Depth was also an important factor across 

regions controlling benthic invertebrate distribution. An important component of the data from 

this fieldwork was height and density information for corals and sponges in the Aleutian Islands. 

These new data and models will be used in the future to inform management decisions on where 

fishing closures can be most effective in protecting the oldest, most diverse, and densest coral and 

sponge communities. 

One of the foundations of the distribution maps for deep-sea corals and sponges is maps based on 

sediment and bathymetry that were developed from the Alaska Initiative. New bathymetry and 

sediment maps for the Aleutian Islands and parts of the Gulf of Alaska were completed during 

this project. These maps mined the NOS charting data as far back as the late 1900s and new 

multibeam bathymetry data from study sites all over Alaska into a single product that was used to 

derive distribution models for deep-sea corals and sponges. Future work will expand geological 

interpretation of these maps and data to provide substrate-based classifications for regions where 

enough supporting data exist.

During the Alaska Initiative, we also tried to document the differences in fisheries productivity 

using a number of measures in different types of habitats (hard substrate with coral, hard 

substrate with no coral, and bare sand habitat). Densities of rockfish, especially juveniles and 

smaller species, was higher in coral habitat than the other types of habitat, which has previously

been shown in other areas by other studies. However, other measures of productivity, such as 

gonosomatic index, relative fecundity, energetic content, and reproductive failure were also 

measured in the different types of habitats, and highest productivity using these measures tended 

to be in the coral habitat. Preliminary results indicate that for rockfish, there may be benefits to 

coral habitat in terms of fish productivity that exceed the benefits of the same type of substrate 

without coral. Further data and results are forthcoming from this project as samples continue to 

be analyzed. 

Because climate change and ocean acidification are expected to have large impacts on high 

latitude systems, such as those found in Alaska, some monitoring programs were set up that used 

existing facilities within the AFSC to collect data. An oceanographic monitoring array was tested 

in Tracy Arm Fjord, Southeast Alaska, and a permanent real-time data delivery station will be 
ix

established at Little Port Walter in Southeast Alaska that will be connected to other 

oceanographic monitoring programs (NESDIS and AOOS). The AFSC bottom trawl surveys also 

have been collecting oceanographic data using equipment purchased by the Alaska Initiative. So 

far, these data have shown distinct breaks and patterns in O2 concentrations in the Gulf of Alaska 

especially. Prior to these collections, no synoptic data sets for summer oceanographic conditions 

throughout Alaska ecosystems were being collected, with the exception of temperature data. Both

these data sets will continue to be monitored and provided to scientists and managers to support 

ecosystem management not only for deep-sea corals and sponges, but for other purposes as well. 

Samples collected during the fieldwork for the Alaska Initiative resulted in the description of 23 

new species of demosponges. Collected samples were also critical to the revision of at least one 

family of demosponge as well as providing geographical range extensions for many species. 

Biochemical analyses and products also have resulted in important and potentially medically 

useful alkaloids. As samples continue to be analyzed, further species and taxonomic revisions are 

likely. These findings highlight the fact that there is still much to be learned about the taxonomy 

of deep-sea corals and sponges in Alaska, but that significant progress has been made partly 

because of the Alaska Initiative. 

In all, the 3-year Initiative provided important new information that addressed both immediate 

management needs for coral and sponge ecosystems (such as the distribution mapping and 

modeling that has already been used by the NPFMC to inform fisheries management), as well as 

longer term goals (such as setting up long-term monitoring stations in Little Port Walter and on 

bottom trawl surveys that will measure the effects of climate change on the ecosystem). Equally as 

important, the Alaska Initiative has raised new questions but provided new techniques that can 

be used to inform future research in Alaska. 
x

Acknowledgments

The Alaska Deep Sea Coral Research Team members are Chris Rooper (AFSC RACE Division), 

Robert Stone (AFSC Auke Bay Laboratories), Peter Etnoyer (NCCOS, Center for Coastal 

Environmental Heath and Biomolecular Research), Jennifer Reynolds (University of Alaska 

Fairbanks), John Olson (NMFS Alaska Regional Office), and John Tomczuk (NOS). We would like 

to thank Kresimir Williams and Rick Towler provided the stereo cameras used in this projects, as 

well as the software used to analyze the stereo camera images. Rachel Wilborn and Pam Goddard 

conducted image analysis for the Aleutian Islands and fish productivity studies. Mark 

Zimmermann, Megan Prescott, Jane Reid and Nadine Golden worked on the bathymetry and 

sediment compilations for the Aleutian Islands and central Gulf of Alaska. Additional funding for 

this project was provided by the Alaska Fisheries Science Center, North Pacific Research Board 

and the Alaska Regional Office.

We thank Captain Jim deLaBruere and the crew of the ADF&G RV Medeia for their assistance 

during the 2013 cruise in the eastern GOA and the 2014 cruise to Holkham Bay to collect genetic 

samples. We thank Julie Nielsen (University of Alaska Fairbanks) for loaning us the acoustic 

release system used during the 2013 cruise. We thank Captain Lou Laferriere and the crew of the 

FV Alaska Provider, Ed Cassano of Ocean Science Service, and the crew at Deep Ocean 

Exploration and Research for their assistance during the 2013 ROV cruise. We thank Ed Cassano 

of Pelagic Research Services and the captain and crew of the RV Dorado Discovery for their

assistance during the 2015 ROV cruise. We thank Captain Dan Foley and the crew of the FV Steller

for their assistance during the 2014 dive cruise to Holkham Bay to deploy equipment for the longterm oceanographic study.

We thank the captains and crew of the commercial fishing vessels that were chartered to 

participate in this research from the F/V GoldRush and the F/V Pacific Storm including B. Ashley, 

D. Ashely, and S. Hockema. We would like to thank D. Benjamin, M. Yang, and A. Vijgen for 

valuable assistance in the field. We also wish to thank the individuals from the Resource Ecology 

and Ecosystem Modeling Food Habitats program including K. Aydin, T. Buckley, R. Hibpshman, 

K. Sawyer, and S. Rohan for their analysis of both the diet and zooplankton data. Additional 

funding sources included North Pacific Research Board and the HEPR Essential Fish Habitat 

program. 

We also thank Tom Hourigan and Fan Tsao at the NOAA DSCRTP whose support was critical to 

the Alaska Initiative.
1

1. Introduction

The Deep Sea Coral Research and Technology Program (DSCRTP) was established under the 

authority of Section 408 of the Magnuson-Stevens Fishery Conservation and Management Act 

(MSA) as reauthorized in 2007 to identify, monitor, and provide information to protect deep-sea 

coral areas. The DSCRTP has supported exploration, research, and management activities critical 

to understanding and managing deep-sea corals and sponges. The objectives of NOAA’s Deep-Sea 

Coral and Sponge Exploration and Research Strategy (NOAA 2010) are to 1) locate and 

characterize deep-sea coral and sponge ecosystems, 2) understand the biology and ecology of 

deep-sea corals and sponges, 3) understand the biodiversity and ecology of deep-sea coral and 

sponge ecosystems, 4) understand the extent and degree of impact to deep-sea coral and sponge

ecosystems caused by fishing and other human activities, and to 5) understand past oceanic 

conditions and predict the impacts of climate change using deep-sea corals. Research activities in 

each of the six NMFS management regions have been supported by the DSCRTP through a series 

of 3-year funding initiatives.

Deep-sea coral and sponge ecosystems are widespread throughout most of Alaska’s marine 

waters. In some places, such as the central and western Aleutian Islands, these may be among the 

most diverse and abundant deep-sea coral and sponge communities in the world. Deep-sea coral 

and sponge communities are associated with many different species of fishes and invertebrates in 

Alaska. Because of their biology, these benthic invertebrates are potentially impacted by climate 

change and ocean acidification. Deep-sea coral and sponge ecosystems are also vulnerable to the 

effects of commercial fishing activities. The challenges facing management of deep-sea coral and 

sponge in Alaska begin with the lack of knowledge of where these organisms occur in high 

abundance and diversity. Because of the size and scope of Alaska’s continental shelf and slope, the 

vast majority of the area has not been surveyed for deep-sea coral and sponge abundance. Since 

the spatial distribution of these communities is not known in Alaska, it is difficult to predict the 

locations and types of human activities and climate impacts that may affect deep-sea coral and 

sponge ecosystems. From 2012-2015, the NOAA Deep Sea Coral Research and Technology Program 

(DSCRTP) sponsored a field research program in the Alaska region. The priorities for Alaska were 

derived from ongoing data needs and objectives identified by the DSCRTP, the North Pacific 

Fishery Management Council and Essential Fish Habitat-Environmental Impact Statement (EFHEIS) process. The objectives of funded research projects were: 

• to identify areas of high abundance of Primnoa corals in the Gulf of Alaska,

• to determine the distribution and areas of high abundance and diversity of sponges and

corals in the Gulf of Alaska and Aleutian Islands,

• to estimate the recovery rates and sustainable impact rates for Primnoa corals in the Gulf 

of Alaska,

• to determine the productivity increases in terms of fish abundance and condition in areas 

with and without corals and sponges,

• to estimate the potential effects of long-line fishing on coral and sponge communities in 

Alaska, 

• to estimate the connectivity of populations of Primnoa in the Gulf of Alaska, British 

Columbia, and the west coast of the U.S. through genetic studies, 

• to collect long-term data sets of O2 and pH from summer bottom trawl surveys, 
2

• to set up long-term monitoring of nearshore and unique populations of coral and sponge 

in SE Alaska fjords, 

• to improve the taxonomy of sponges and corals through special collections of unidentified 

specimens and collect data and specimens for paleoclimatological, microbial, and marine 

natural product studies, and

• to compile a geologically-based substrate map for the Gulf of Alaska and Aleutian Islands.

The research was carried out by AFSC scientists from the Auke Bay Laboratories and the Resource 

Assessment and Conservation Engineering Division, the Alaska Regional Office, as well as 

partners at the University of Alaska Fairbanks, the US Geological Survey, NCCOS, the Tombolo 

Institute, the University of Maine, and the Alaska Department of Fish & Game. Supplemental 

funding was provided by the AFSC and the North Pacific Research Board.

2. Major Field Research Projects

Three of the projects conducted as part of the Alaska deep-sea coral and sponge initiative 

included dedicated at-sea cruises and fieldwork spread across multiple years. These projects were 

the southeast Alaska Primnoa study, the Aleutian Islands mapping study and the Gulf of Alaska 

fish productivity study (Figure 1). In all, there were nine separate research cruises carried out with 

a total of 109 at-sea days (Table 1).

Figure 1. Locations of research cruises funded in FY12-15 by the Deep-Sea Coral Research and Technology 

Program. The Aleutian Islands mapping project was conducted in the area outlined by the red border, the fish 

productivity project was conducted at the two sites indicated by orange circles, and the Alaska Primnoa study 

was conducted at the four of the five sites (Cape Ommaney, Prince of Wales, Dixon Entrance and Fairweather 

Ground) in the eastern Gulf of Alaska indicated by green circles.
3

Table 1. List of cruises by project for the Alaska Coral and Sponge Initiative (FY12-15). 

Project Study sites Cruise dates Vessel Survey tools Purpose Participating scientists

Southeast Alaska 

Primnoa study1

Dixon Entrance, Shutter Ridge, 

Prince of Wales, Chirikof Island

June 1-13, 2012 R/V 

Pacific 

Star

Multibeam 

sounder

Map study areas 

using multibeam 

sounder

J. Reynolds

Dixon Entrance, Shutter Ridge, 

Prince of Wales, Fairweather 

Ground

August 7-21, 

2013

F/V 

Alaska 

Provider

ROV Survey transects, 

collect specimens 

for analysis

R. Stone, J. Reynolds, 

G. Greene, P. Etnoyer, 

C. Morrison, A. Turner

Shutter Ridge, Fairweather 

Ground

August 13-18, 

2013

R/V 

Medeia

Towed 

camera

Deploy settlement 

plates, survey 

transects

C. Rooper

Dixon Entrance, Shutter Ridge, 

Fairweather Ground, 

Edgecumbe Pinnacle

June 1-11, 2015 R/V 

Dorado 

Discovery

ROV Survey transects, 

collect specimens 

for analysis, collect 

settlement plates

R. Stone, J. Reynolds, 

C. Morrison, R. 

Salgado, R. McGuinn, 

K. Feehan

Aleutian Islands 

mapping study

Eastern and central Aleutian 

Islands, Bowers Bank and Ridge

August 14-29, 

2012

F/V Sea 

Storm

Towed 

camera

Occupy random 

stratified survey 

transects

C. Rooper, R. Stone

Central and western Aleutian 

Islands

April 20-May 

14, 2014

F/V 

Alaska 

Endeavor

Towed 

camera

Occupy random 

stratified survey 

transects

C. Rooper, J. Olson

Gulf of Alaska fish 

productivity 

study1,2

Forty-nine fathom pinnacle August 15-21, 

2012

F/V 

Pacific 

Storm

Towed 

camera, 

trawl

Collect fish

samples, survey 

transects

C. Conrath, B. Knoth, 

M-S Yang, D. Benjamin

Forty-nine fathom pinnacle 

and Snakehead Bank

May 10-17, 

2014

F/V Gold 

Rush

Towed 

camera, 

trawl

Collect fish 

samples, survey 

transects

C. Conrath, B. Knoth

Forty-nine fathom pinnacle 

and Snakehead Bank

December 10-

18, 2014

F/V Gold 

Rush

Towed 

camera, 

trawl

Collect fish 

samples, survey 

transects

C. Conrath, A. Vigjen

1

Partially funded by Alaska Fisheries Science Center

2 Funded by North Pacific Research Board
4

2.1 Red tree coral (Primnoa pacifica) thicket habitats in the eastern Gulf of Alaska

Background and Objectives: This research examined the biology and ecology of red tree corals 

(P. pacifica) at five study areas in the eastern Gulf of Alaska (GOA; Figure 2). Red tree corals are 

large gorgonians or sea fans that are the dominant structure forming coral species on the outer 

continental shelf and upper slope between the Alaska Peninsula and the Olympic Coast Marine 

Sanctuary off Washington State. Red tree corals form dense thickets in some areas of the North 

Pacific Ocean but their precise location is largely unknown and can often only be inferred from 

spatially imprecise sources such as fisheries bycatch data. Observations have confirmed the 

presence of thickets at several locations between the Fairweather Ground in the northeastern 

GOA and Bowie Seamount in northern British Columbia. The importance and vulnerability of red 

tree coral thickets has been recognized by the North Pacific Fishery Management Council 

(NPFMC) and some protection has been afforded to known thickets in the region through the 

establishment of five small Habitat Areas of Particular Concern (HAPCs). The HAPCs where all 

fishing activities are prohibited were established in 2007.

Colonies tend to be located on moderate relief bedrock and large boulders (glacial drop stones) 

which are also areas where bottom-contact fishing gear, principally set gear such as longlines, are 

used. Red tree corals are common bycatch in fisheries for demersal species and in stock 

assessment surveys. Colonies are easily damaged or dislodged from the seafloor by natural forces, 

such as landslides and low-level predation and unnatural forces, such as bottom fishing activities. 

Manned submersible observations in the GOA clearly indicate that some thickets have been 

disturbed by past fishing activities (Stone et al. 2014). Derelict longline gear has been observed 

entangled in coral colonies at several sites in the eastern GOA and some thickets have colony 

damage rates exceeding 16% (Stone et al. 2014). Owing to their large size, arborescent growth 

pattern, and reported slow growth rates, red tree corals are highly susceptible to disturbance from 

fishing activities and are likely slow to recover from such disturbance. Red tree corals have 

specifically been identified as important habitat for fishes and invertebrates in the Gulf of Alaska. 

Previous research in eastern GOA thickets indicates that red tree corals are found on bedrock 

where the seafloor is rough and sloped (Masuda and Stone 2015). Otherwise we know little about 

the habitat requirements or the specific geological features that may control the establishment of 

thickets. This lack of basic knowledge inhibits effective management of red tree coral habitats in 

the face of anthropogenic disturbances and the potential effects of climate change and ocean 

acidification. Data collected during this study will provide important insights regarding the most 

appropriate tools available to resource managers to protect sensitive coral habitats and the 

ecosystem services they provide.

The objective of this research was to study the ecology and geology of seafloor habitats at several 

sites known to or suspected of supporting red tree coral thickets in the eastern GOA. We 

produced high-resolution bathymetry and seafloor habitat maps to identify targets of high 

interest and then used remotely operated vehicles (ROVs) to ground-truth and explore those 

targets for coral and sponge habitats. Results of this research will be provided to the NPFMC to 

modify the boundaries of the existing HAPCs and establish new HAPCs in the region if warranted. 

Approach: We conducted a research cruise aboard the R/V Pacific Star between 4–15 June and 11–

12 July 2012 to collect multi-beam and backscatter data at four sites in the Gulf of Alaska (Sites 1, 2, 

4, and 6; Figure 2). Sites 3 and 5 had been mapped during previous research projects. Fugro-
5

Pelagos, Inc. was contracted to collect and process the seafloor imagery data. Each site was 

mapped (100 percent coverage) to ~800 m depth with a Reson Seabat7111 multi-beam sonar 

operating at 110 kHz. Bathymetry and backscatter maps for each of the study areas were produced 

in August 2012. In total, 522.8 linear nautical miles were mapped over an area of 167.2 square 

nautical miles. Mapped areas ranged in depth from approximately 100 to 1287 m. 

Seafloor maps were used to identify hard, rough substrates that were potential targets for the 

presence of red tree coral thickets. Maps were also used to plan ROV dives to explore various 

geographical features for the presence of corals. In August 2013 we used the Deep Ocean 

Exploration and Research H2000 ROV to conduct dive operations at three sites (Sites 1, 2, and 3) 

in the eastern GOA. In June 2015 we used the Pelagic Research Services and Odyssey Marine ROV 

Zeus II to conduct dive operations at four sites in the eastern GOA (Figure 3). Dive Site 6 in the 

western GOA was not explored during either year of this study due to budgetary constraints. The 

ROVs were used to collect video footage of the seafloor along strip transects chosen at random 

locations within the high priority areas that comprised suitable substrate for red tree corals. 

Transects covered a broad depth range spanning 1000 to 80 m at each site. Video footage of the 

seafloor was collected with at least two cameras. The primary camera was mounted with the 

imaging plane directed nearly perpendicular to the seafloor so as to provide a fixed-width (~120 

cm) image area from which counts of biota were made. The width of the image area was be 

delineated by two parallel lasers (wavelength = 532 nm) mounted on the “brow bar” of the ROV. A 

secondary camera with pan, tilt, and zoom functions was mounted forward and controlled by the 

science team to provide close-up imagery of the transect and collected specimens. In addition, all 

video cameras recorded two parallel laser marks (wavelength = 670 nm) 10 cm apart projected 

onto the seafloor to provide calibration for measurements of the dimensions of the image area 

(i.e. transect width and length), and size of fauna. The ROV was equipped with a SeaBird CTD or 

other oceanographic sensors used to collect depth, temperature, and salinity profiles along the 

entire ROV dive track at regular (e.g., 2 second) intervals. All imagery, oceanographic, and 

navigational data was cross-referenced and synchronized with time stamping set to the ROV 

tracking system onboard the support vessel.

In August 2013 we chartered the Alaska Department of Fish & Game (ADF&G) RV Medeia to place 

settlement arrays on the seafloor at Site 3 (Shutter Ridge) and Site 4 (Fairweather Ground). 

During that cruise we also collected video imagery of the seafloor at both sites along select 

transects using a stereo-video drop camera system deployed from an oceanographic winch. The 

camera system was towed at slow speed along a pre-determined bearing just above the seafloor 

and recorded still images once per second. At Site 3, images were collected along two transects, 

one south and one north of existing surveys to determine if red tree coral thickets extended to 

regions beyond the Shutter Ridge proper. At Site 4, images were collected along several transects 

along the continental slope and shelf previously not explored. 

Preliminary analysis of video footage occurred onboard the support vessel, but the bulk of the 

analysis has and will occur in the videographic laboratories at the Auke Bay Labs and NOS Center 

for Coastal Environmental Health and Biomolecular Research (NOS/CCEHBR). In the laboratory, 

all corals, sponges, fish and large invertebrates (including the predatory seastar Hippasteria

phrygiana) within the strip transect video will be enumerated. Corals and sponges will be

classified as damaged if they have missing or broken branches, are detached from the seafloor, or 

are attached but overturned and lying in contact with the seafloor. Evidence for the nature of the 

disturbance, e.g., natural disturbance by slumps, landslides, or earthquake events, anthropogenic 
6

disturbance by fishing gear, or predation will be noted. Mobile fauna (fish and crabs) will be 

enumerated if they are observed within the bounds of the strip transect and their presence on the 

transect does not appear to be in response to the ROV (Figure 4). Habitat variables will be 

recorded using established criteria for the region (Stone et al. 2014) and will include depth, 

substrate, slope, roughness, and slope aspect. All data will be archived and made available at 

NOAA’s National Database for Deep-Sea Corals and Sponges. 

Significant Results to Date: The August 2013 cruise with the ADF&G RV Medeia produced two 

stereo-video transects at Site 3 (Shutter Ridge) that confirmed the presence of red tree corals 

beyond the existing HAPC to the south and extended the known distribution of red tree coral 

thickets to the north, beyond the Shutter Ridge proper. These data will be a valuable 

consideration should the existing boundaries of the HAPC be re-evaluated by the NPFMC in the 

future. Data collected on two stereo-video transects on the deep slope (740–300 m depth) at Site 4 

(Fairweather Ground) provided valuable information to ground-truth the multi-beam and 

backscatter data previously collected. The video data also revealed that these sites on the 

continental slope were relatively devoid of red tree corals in this region but do contain small 

numbers of black corals (Chrysopathes spp., Bathypathes sp., and Dendrobathypathes boutillieri), 

hydrocorals (Stylaster spp.), bamboo corals (Isidella tentaculum and Keratoisis sp.), and other 

octocorals Paragorgia sp., Psammogorgia simplex, Swiftia pacifica, Halipteris sp., and soft corals 

(Heteropolypus sp.).

ROV dives at Site 1 (Dixon Entrance) in 2013 and 2015 focused on two areas; the deep (~350 m 

depth) basin in soft-sediment habitats with scattered glacial drop-stones and several hard-bottom 

areas along the upper slope and outer shelf of the basin (~165 m depth). The deeper area was the 

site of prior submersible exploration by AFSC scientists in the 1990s (Krieger 2001, Krieger and 

Wing 2002) and 2005 (R. Stone, unpublished data). An important observation during this study 

was that the condition of the red tree corals has markedly degraded since the earlier observations 

with the majority of colonies partially or completely skeletonized. Many colonies had signs of 

damage, likely from longline fishing gear (Figure 5), and predation by the three predators of red 

tree corals documented in the region (Stone et al. 2014). Analysis of all video footage is planned in 

the future to document the apparent demise of the deep corals and investigate possible 

mechanisms that might include ocean warming, ocean acidification, increased fishing activity, 

and shifts in community structure. Observations made during exploration of the two shallow sites 

revealed previously undocumented red tree coral thickets with large numbers of associated 

rockfish (Sebastes spp.) on bedrock outcrop features (Figure 6). 

Five ROV dives were made at Site 2 (Prince of Wales) in 2013 to investigate areas where red tree 

coral bycatch in AFSC longline surveys had previously been documented and to explore 

interesting geological features revealed on the multi-beam and backscatter data. A single dive was 

made in deep water (600–500 m) on the continental slope and revealed mixed-substrate habitats 

with only a few black corals (Bathypathes sp.) and pennatulaceans (Halipteris sp.). Four ROV 

dives were made on the shelf (~250 m depth) and revealed that the interesting “pock marks” 

observed on the seafloor imagery were depressions and mounds, with rims of carbonate crusts, 

and possibly relic cold seeps. The carbonate crusts provided some hard substrate for sponges but 

otherwise the shelf regions were relatively devoid of corals. 
7

ROV dives at Site 3 (Shutter Ridge) in 2013 and 2015 were used to support other aspects of this 

project only. Since the entire ridge had previously been explored (Stone et al. 2014, Masuda and 

Stone 2015) additional reconnaissance dives were not warranted with the ROV. 

ROV dives at Site 4 (Fairweather Ground) were limited to 2015 as inclement weather and high 

seas prevented ROV operations in 2013. A total of six reconnaissance dives were made in 2015 and 

included four dives on volcanic and other bedrock features on the shelf (190–140 m depth) and 

two dives on the slope including submarine canyons (625–320 m depth). The deeper dives 

revealed that the slope in the region is principally composed of unconsolidated sediments. A few 

areas of siltstone and bedrock outcrop provide suitable substrate for black corals (Chrysopathes

spp., Bathypathes sp., and Dendrobathypathes boutillieri), hydrocorals (Stylaster spp.), bamboo 

corals (Isidella tentaculum and Keratoisis sp.), and other octocorals Paragorgia sp., Psammogorgia 

simplex, Swiftia pacifica, Halipteris sp., and soft corals (Heteropolypus sp.). We did find a few red 

tree corals growing at depths of 398 m but no thicket habitat. We found new red tree coral 

thickets on the four ROV dives made on the shelf habitats. These were newly explored areas, not 

within the four existing HAPCs at this site, so will provide valuable data for consideration should 

the existing boundaries of the HAPC be re-evaluated by the NPFMC in the future.

A single ROV dive at Site 5 (Edgecumbe Pinnacle) in 2015 explored a volcanic cone (183–153 m 

depth) discovered in the early 1990s with the submersible Delta during ADF&G groundfish stock 

assessment surveys. The volcanic feature is located off the SW end of Kruzof Island at 57° 05.621' 

N, 136° 07.356' W. We video documented the geological and biological features of the cone by 

conducting a transect from the base of the feature to the summit. First, we circumvented the 

feature in a counterclockwise fashion beginning on the eastern side until we encountered a debris 

field containing shells of the giant barnacle (Chirona evermanni) where they were collected. The 

calcareous plates or “mouthparts” of the barnacles, the terga and scuta, will be aged and used as a 

proxy to reconstruct the volcanic timeline of the feature. Additionally, scattered red tree corals 

were found on pillow basalt from the bottom to the top of the cone.

Funding: DSCRTP funds ($324,352) were used in FY2012 to support the multi-beam mapping 

contract. DSCRTP funds ($498,500) were used in FY2013 to support the ROV and vessel charter, 

the RV Medeia charter, and other project costs. DSCRTP funds ($455,666) were used in FY2014 

and FY2015 to support the ROV and vessel charter and other project costs. Additionally, the AFSC 

provided supplemental funding ($231,717) in FY2015 to make this project whole. Travel, salary and 

benefits costs for the principal investigators and all science team members were in-kind 

contributions by their supporting agencies.

Points of Contact: 

Robert Stone (bob.stone@noaa.gov), NOAA Fisheries, Auke Bay Laboratories

Jennifer Reynolds (jrreynolds@alaska.edu), University of Alaska, Fairbanks

Gary Greene, University of California, Davis & the Tombolo Institute

Additional collaborators: 

Cheryl Morrison (USGS, Leetown Science Center), Ren Salgado (NOAA Fisheries, 

NOS/NCCOS/CCEHBR), Peter Etnoyer (NOAA Fisheries, NOS/NCCOS/CCEHBR), Chris Rooper 

(NOAA Fisheries, AFSC), Robert McGuinn (NOAA Fisheries, NOS/NCCOS/CCEHBR), Alec 

Turner (College of Charleston & Grice Marine Laboratory), Agno Rubim de Assis (University of 

Alaska, Fairbanks), Keri Feehan (University of Maine at Orono) 
8

Figure 2. Map of Alaska showing the six study sites. Sites 1–5 (Dixon Entrance, Prince of Wales, Shutter Ridge, 

Fairweather Ground and Edgecumbe Pinnacle) were surveyed with remotely operated vehicles in the eastern 

Gulf of Alaska in 2013 and 2015. Site 6 (Chirikof) was not surveyed using remotely operated vehicles.
9

Figure 3. The ROV Zeus II, used during the 2015 expedition, is recovered after a dive at the Fairweather Ground 

(Site 4) where it collected a large red tree coral colony for age and paleo-climatological analyses.

Figure 4. A large rougheye rockfish (Sebastes aleutianus) in a red tree coral colony at a depth of 347 m in the 

Dixon Entrance basin (Site 1). The coral is attached to a large glacial drop-stone and is being preyed upon by 

calliostomatid snails (Otukaia sp.).
10

Figure 5. Longline damage to a large red tree coral at a depth of 193 m at the Shutter Ridge (Site 3). 

Figure 6. Redbanded rockfish (Sebastes babcocki) are common residents in red tree coral thickets, this one at 

207 m at the Shutter Ridge (Site 3). The large glass sponge (Farrea occa) is also common in red tree coral 

thickets and grow to more than 3 m in diameter.
11

2.2. Mapping and modeling coral and sponge distribution in the Aleutian Islands

site

Background and Objectives: Effective management of deep coral and sponge ecosystems in 

Alaska requires knowledge of where these organisms occur and patterns in diversity and 

abundance. Because of the size of Alaska’s marine environment it is not possible to assess the 

distribution of coral and sponge at every location in Alaska, so a systematic and statistically 

rigorous methodology was necessary to determine likely coral and sponge habitat throughout 

Alaska. Spatial distribution models based on bottom trawl survey were developed for all regions of 

Alaska where coral are known to occur (Rooper et al. 2014, Sigler et al. 2015, Rooper et al. in 

review, see section 3.3), however, testing of the modeled distribution was necessary to see if 

bottom trawl catches truly were able to capture the distribution of corals and sponges in Alaska. 

The objectives of this fieldwork were to collect density and size estimates for corals and sponges 

at randomly selected sites in the Aleutian Islands and document species associations with fish and 

invertebrates.

Approach: We used a survey design that was depth stratified and incorporated randomly selected 

stations in the Aleutian Islands from Unimak Pass to Stalemate Bank (and including Bowers Ridge 

and Bank). Depths ranged from ~30 to ~900 m. At each station we deployed a stereo camera 

system and collected 15 minutes of on bottom imagery. Images were analyzed by identifying and 

measuring (using stereoscopy) benthic invertebrates and fishes. Substrate type was also recorded.

Significant Results to Date: The groundtruthing observations supported the bottom trawl 

survey models for corals, accurately predicting presence or absence in ~80% of cases (AUC ~ 0.59-

0.81). Predicted and observed coral densities were significantly correlated in all cases (p < 0.001), 

however, the proportion of variance explained was relatively minor (17-30%). For sponges, the 

groundtruthing data provided less support for the modeling, with only about 55% of the 

observations predicted accurately (AUC = 0.59). Sponges were observed at 178 of 216 camera 

stations, corals (including hydrocorals and octocorals) were observed at 139 stations and 

pennatulaceans (sea whips and pens) were observed at 81 stations. Observed sponge densities 

were significantly correlated with predicted sponge densities (p = 0.001) however. This was an 

interesting result in that sponges were observed at 82% of camera stations, a higher number than 

the bottom trawl survey data used in the modeling (Rooper et al. 2014). The model used only 

“upright” sponge morphologies estimated from trawl catches, while all morphologies were 

counted from the image data. This may account for both the higher prevalence of sponge in the 

image data and the relatively poor fit for the observations versus models (Rooper et al. in review).

Corals from the family Primnoidae dominated the species observed in the Aleutians, and these 

corals were found in high densities roughly from Seguam Pass to Tahoma Reef (Figure 7). Sponges 

were widely distributed in high densities across the region, while sea pens and sea whips were not 

as dense as other benthic invertebrates (Wilborn et al. in review). Mean height across all taxa was 

between 20 and 40 cm, except sea whips (Figure 8). Corals were observed almost exclusively on 

hard-bottom substrates (Figure 9)

Funding: DSCRTP funds ($192,783) were used in FY2012 to support a 12 day vessel charter in the 

Aleutian Islands and other project costs. DSCRTP funds ($163,072) were used in FY2013 to support 

a 12 day vessel charter in the Aleutian Islands and other project costs. DSCRTP funds ($205,697) 

were used in FY2014 to support a 14 day vessel charter in the Aleutian Islands and other project 

costs. Travel, salary and benefits for science team members were contributed by the AFSC.
12

Point of Contact: Chris Rooper AFSC-RACE Division (chris.rooper@noaa.gov) 

Site Characterization Report: http://www.afsc.noaa.gov/techmemos/nmfs-afsc-313.htm

Figure 7. Densities of various benthic invertebrates from the towed camera fieldwork conducted in the 

Aleutian Islands in 2012 and 2014.
13

Figure 8. Mean height (and standard error) of coral and sponge observed in the Aleutian Islands. 

Figure 9. Example images from the Aleutian Islands.

2.3 Productivity of FMP species in coral and sponge habitats in the Alaska region. 

Background and Objectives: Associations of rockfish and other species with coral and sponge 

communities is well established in Alaska (Heifetz et al. 2002, Malecha et al. 2005, Rooper and 

Boldt 2005, Rooper et al. 2007, Stone 2014, Laman et al. 2015). The contribution of coral and 

sponge habitat to fish productivity as compared to other non-biotic complex structure (e.g.,

boulders) for the productivity of rockfish and other FMP species remains unknown. These 
14

complex habitats likely provide enhanced food resources, protection from predators, and a refuge 

from strong ocean currents. The vulnerability of these habitats to fishing gear (Heifetz et al. 2009, 

Stone 2014) is of concern and further emphasizes the need to better understand these ecosystems. 

The overarching goal of this study is to examine the productivity of FMP species within coral and 

sponge habitats in the Gulf of Alaska. 

Approach: Two areas within the central Gulf of Alaska were sampled during three seasons

(Figure 10). During each sampling cruise a variety of platforms were used to collect physical and 

biological data from coral, boulder, and bare habitats. A comparative approach was used to 

examine differences in community structure, diet, prey availability, energetic content, growth, 

and reproductive productivity of FMP species within these habitats. 

Figure 10. Location of study sites for FMP production study in the Gulf of Alaska.

Significant Results to Date: Preliminary results indicate that the coral habitat at the 49 Fathom 

Pinnacle site was dominated by Stylaster hydrocorals. Hexactinellid sponges were also frequently 

observed. In contrast, preliminary results indicate the coral habitat at the Snakehead site was 

dominated by the gorgonian corals, including Fanellia frasieri, Plumarella spp. and Plexauridae.

Densities of gorgonian corals and sponges from the coral present sites averaged 0.050 and 0.052 

colonies*m-2 respectively. Preliminary CPUE estimates of rockfish density from the SDC video 

49 Fathom Pinnacle

Snakehead Bank
15

drops indicate significant differences in rockfish density among habitats, with highest densities in 

the boulder and coral habitats at both sampling sites. 

Trawl catches at the 49 Fathom Pinnacle site consisted predominately of adult dusky and 

northern rockfish throughout this sampling area though Pacific ocean perch (POP) occur along 

the deeper edges of this site. Preliminary data from the second sampling site (Snakehead) indicate 

that this area has a much higher abundance of small rockfish including juvenile POP, juvenile 

northern rockfish, juvenile redstripe rockfish, and juvenile and small adult species including 

harlequin and pygmy rockfish. 

Preliminary energetic and reproductive results of dusky and northern rockfish reveal differences 

in productivity of these species across the three habitats. In the low relief habitat, energy content 

was the highest in the winter for both northern and dusky rockfish, while in the high relief coral 

habitat, the energy content in the winter for the same species was the lowest. Energy content of 

all three species in the high relief rocky/boulder and high relief coral/sponge habitats were 

similar, with the northern rockfish having the higher energy content of the two species in both 

habitats. Differences in the gonadosomatic index and relative fecundity varied between the two 

sampling sites and the three habitats within each sampling site with the highest productivity 

measures occurring in the coral habitat for both northern and dusky rockfish (Figure 11). A 

portion of both dusky and northern rockfish sampled for this project had evidence of partial or 

total reproductive failure due to either skip spawning or fertilization failure. Reproductive failure 

was consistent across habitats for northern rockfish but for dusky rockfish was lower in coral 

habitats (Figure 11).

Funding: In FY12, $150,340 in DSCRTP funds were used to support vessel charters, sample 

processing contracts and other project costs. In FY13 funding was received from both the DSCRTP 

($116,020) and a successful proposal to the AFSC Habitat and Ecological Processes Research 

Program (HEPR; $31,800) to support fieldwork. In FY14 only $38,180 was received from the 

DSCRTP to support sample processing for this project. Additional fieldwork on this project in 

FY13 and FY14 was supported by a funded proposal to the North Pacific Research Board ($272,321). 

Travel, salary and benefits for science team members were contributed by the AFSC.

Point of Contact: Christina Conrath AFSC-RACE Division (christina.conrath@noaa.gov) 

Site characterization report: Available at 

https://www.afsc.noaa.gov/Publications/ProcRpt/PR2017-06.pdf. 
16

Figure 11. Preliminary reproductive productivity of northern and dusky rockfish during the month of May 2014, 

measured as a) gonadosomatic index, b) relative fecundity, and c) reproductive failure, separated by habitat 

and site. 49 FP = the 49 Fathom Pinnacle site, and SHB = the Snakehead Bank site. 

0.05

0.06

0.07

0.08

0.09

0.1

0.11

0.12

0.13

0.14

Bare 49 FP Boulder 49 FP Boulder SHB Coral 49 FP Coral SHB

GSI

Habitat

Northern RF

Dusky RF

50

60

70

80

90

100

110

120

130

Bare 49 FP Boulder 49 FP Boulder SHB Coral 49 FP Coral SHB

Relative Fecundity

Habitat

Northern RF

Dusky RF

0

5

10

15

20

25

30

35

Bare 49FP Boulder 49FP Boulder SHB Coral 49FP Coral SHB

Reproductive Failure

Habitat

Dusky RF

Northern RF

a)

b)

c)
17

3. Associated studies

In addition to the three major field research projects, a number of other studies were undertaken 

during the Alaska Coral and Sponge Initiative. Some of these projects involved fieldwork or field 

collection of data, but these projects were piggy-backed onto existing cruises or existing activities 

at the Alaska Fisheries Science Center.

3.1. Recruitment of red tree coral (Primnoa pacifica) in thicket habitats in the 

eastern Gulf of Alaska

Background and Objectives: Recruitment of sedentary fauna is a critical component of seafloor 

habitat recovery. Very little is known about the mechanisms and periodicity of recruitment by 

corals but observations in the Gulf of Alaska indicate that it is episodic and occurs infrequently 

(Stone et al. 2014, Stone et al. 2017). Understanding the dynamics and habitat requirements of 

coral recruitment will provide important information for the management of fisheries habitat. 

The objectives of this study were to determine the periodicity of recruitment for red tree corals 

and examine the dynamics of larval dispersal. 

 

Approach: In August 2013 we chartered the Alaska Department of Fish & Game (ADF&G) RV 

Medeia to place four settlement arrays on the seafloor in two areas of high red tree coral 

abundance (Site 3 - Shutter Ridge, and Site 4 - Fairweather Ground). Arrays were slowly lowered 

to the seafloor with an oceanographic winch. The exact position and depth of each array 

deployment was recorded. The deployment array consisted of an Ixsea Oceano shallow water 

acoustic release system and a stereo camera system. Each array measured 100 cm X 100 cm X 5 cm 

and consisted of four blocks of the same type of rock found at the study sites (granodiorite, 

greenstone, and greywacke). Each array had a stainless-steel lifting point and a location marker 

consisting of a 3-m polypropylene line attached to a small trawl float. A Star-Oddi DST centi-T 

recorder was attached to each polypropylene line and programmed to record temperature and 

depth every six hours for the life of the deployment (up to 4 years). 

In June 2015 we charted the RV Dorado and using the ROV Zeus retrieved two settlement arrays at 

Site 4 and one array at Site 3 (Figure 12). We additionally located but did not retrieve a second 

array at Site 3 and collected detailed video footage of the array. Before each retrieval we videodocumented each array and the surrounding habitat (Figure 13). Samples were collected from 

each adult coral colony (> 40-cm height) within a 10-m radius of each array. From each sample we 

will examine genetics, gender, and reproductive parameters. On deck, all organisms that recruited 

to the blocks were collected. The blocks were thoroughly cleaned, temperature recorders were 

replaced, and the arrays were then redeployed with the ROV in the same approximate location 

and in immediate proximity to adult coral colonies (Figure 14). 

In the laboratory, recruited organisms were examined with a stereo microscope (Leica S8 AP0) 

and photographed with a Moticam 5 camera attachment used to grab images (Figure 15). The 

length of each recruit was determined from each photograph. Samples from each recruit were 

collected for genetics to determine if nearby adults are potentially the parents of the recruits, 

thereby providing us with important larval dispersal distance information. 
18

Significant Results to Date: Three settling arrays were retrieved at two study sites (one at Site 3 

and two at Site 4) in June 2015 using the ROV Zeus. Despite the fact that the three sampling arrays 

had been deployed for about 22 months and in close proximity to large, mature red tree coral 

colonies we found no new red tree coral recruits. We observed several known predators of red 

tree corals (Stone et al. 2014) on and near the settling plates so it is possible that predation is a 

major limiting factor to recruitment as previously noted for the Atlantic congener of P. pacifica in 

the Atlantic (Lacharité and Metaxas 2013). The settling array retrieved at Site 3 did however have 

numerous small recruits of the holaxonian Calcigorgia spiculifera on both the settling blocks and 

the marker buoy line (Figure 15). This was surprising since we observed no potential parent 

colonies in the immediate area of the settling plates, although C. spiculifera is locally abundant 

further upslope on the rocky pinnacles that form the ridge. The settling arrays were cleaned and 

redeployed in the same general areas with the intent to retrieve all arrays during the next 

opportunity.

The three temperature probes retrieved at the two study sites provided valuable data on the 

current thermal regime experienced by red tree corals. Of particular relevance was the high 

temperatures (10°C) experienced by corals during November 2014; temperatures known to be well 

within the lethal range for red tree corals held in the laboratory (R. Stone, unpublished data). The 

annual mean temperature at a depth of 197 m (Site 3) was 0.36°C warmer in 2014 (6.23°C) than in 

2013 (5.87°C) and the annual mean temperature at a depth of 143 m (Site 4) was 0.90°C warmer in 

2014 (7.33°C) than in 2013 (6.43°C). These observations indicate that the “warm blob” experienced 

in the North Pacific Ocean in 2014-2015 reached to depths occupied by red tree corals, possibly 

putting them under severe thermal stress. 

Funding: Deployment of the settlement arrays in 2013 from the ADF&G RV Medeia and recovery 

of two arrays in 2015 with the ROV Zeus were supported with DSCRTP (Alaska 3-year Initiative) 

funds as part of Project 1. DSCRTP (Alaska 3-year Initiative) funds ($5,000) were used in FY2012 

for the construction and purchase of supplies and materials for the settlement arrays and 

oceanographic equipment. 

Points of Contact: 

Robert Stone (bob.stone@noaa.gov), NOAA Fisheries, Auke Bay Laboratories 

Cheryl Morrison (cmorrison@usgs.gov), US Geological Survey (USGS), Leetown Science Center

Rhian Waller (rhian.waller@maine.edu), University of Maine at Orono
19

Figure 12. Retrieval of array # 8 at Site 4 (Fairweather Ground) at a depth of 140 m.

Figure 13. Retrieval of array # 8 at Site 4 (Fairweather Ground) showing heavy growth of hydroids after a 22-

month deployment.
20

Figure 14. Re-deployment of array #5 at Site # 4 (Fairweather Ground) at a depth of 143 m.

Figure 15. A new recruit (2-polyp stage) Calcigorgia spiculifera collected on one of the settling arrays at Site 3 

(Shutter Ridge) in June 2015.
21

3.2 Reproductive ecology of red tree coral (Primnoa pacifica) in thicket habitats in 

the eastern Gulf of Alaska 

Background and Objectives: Understanding the reproductive ecology of red tree corals, the 

largest and often most abundant coral species in the northeast Pacific Ocean, is important to help 

gauge how this species and other cold-water corals may respond to disturbance and their 

capability to recover from seafloor perturbation. Studies of this kind are very difficult to conduct 

given the remote and deep-water environments that most corals inhabit and the large number of 

samples necessary. Fortunately we had year-round access to an emerged population or red tree 

corals in Tracy Arm, Holkham Bay, Southeast Alaska. We conducted a study there on 

reproductive ecology (e.g., reproductive mode, seasonality and fecundity) of red tree corals with 

the intent to use the information as a proxy for the deep-water populations that are subjected 

periodically to fishing disturbance (Waller et al. 2014).

Females within the population developed asynchronously, although males showed trends of 

synchronicity, with production of immature spermatocysts heightened in December/January and 

maturation of gametes in the fall months. Seasonality of individuals varied from a single year 

reproductive event to more than the 16 months and multiple stages of gametes occurred in polyps 

of the same colony during most sampling periods. Mean oocyte size ranged from 50 to 200 μm in 

any season and maximum oocyte size (802 μm) suggest a lecithotrophic larvae. No brooding 

larvae were found during the study, although unfertilized oocytes were found adhered to the 

outside of polyps, where they are presumably fertilized. This species has size-dependent 

reproduction, with gametes first forming in colonies over 42-cm in height (an approximate age of 

23 years), and steady oocyte sizes being achieved after reaching 80-cm in length. The average 

fecundity of this species is 86 (±12) total oocytes per polyp, and 17 (±12) potential per polyp 

fecundity. Sub-lethal injury by removing 21–40% of colony tissue had no significant reproductive 

response in males or females over the course of this study, except for a corresponding loss in 

overall colony fecundity. The reproductive patterns and long gamete generation times observed 

indicate that recruitment events are likely to be highly sporadic increasing its vulnerability to 

anthropogenic disturbances.

Approach: Sub-samples of red tree corals were collected at Study Sites 1, 3, and 4 with the goal of 

sampling at least 15 female and male colonies at each site. Samples were used to determine the 

gender, fecundity (females only) and stage of development for both male and female colonies. 

These data will be used to validate the recent findings from the shallow-water population in Tracy 

Arm regarding seasonality, reproductive schedule, and the relationships of environmental 

variables with development and colony size with fecundity. Data on the reproductive timing and 

larval dynamics, especially the mode of larval dispersal, of deep-water octocorals fills a major void 

in our knowledge of the relationships among the major anthozoan groups. 

Significant Results to Date: All samples collected from the three study sites in the Gulf of 

Alaska have been processed in the laboratory and examination of processed samples for 

reproductive parameters is underway. At Site 1, 16 females and 7 males have been examined. At 

Site 3, 20 females and 23 males have been examined. And at Site 4, 13 females and 9 males have 

been examined. Additional samples at Sites 1 and 4 are being examined so that we have a 

minimum sample size consisting of 15 colonies of each gender. 
22

Preliminary observations indicate that the deep-water populations have similar reproductive 

strategies (i.e. gonochorism and multiple developing cohorts of oocytes) to the shallow-water 

population. The deep-water populations, however, appear to have greatly reduced fecundity as is 

often observed in populations of the same species residing in deeper water. We will also compare 

all reproductive parameters between sites that will allow us to determine differences associated 

with latitude and depth. 

Funding: Collection of the samples was supported with DSCRTP (Alaska 3-year Initiative) funds 

as part of Project 1 in 2013 and 2015. Funding for field work assistance and laboratory analyses by 

the University of Maine was provided by the AFSC ($60,326) through a successful proposal to the 

HEPR program.

Points of Contact: 

Rhian Waller (rhian.waller@maine.edu), University of Maine at Orono 

Robert Stone (bob.stone@noaa.gov), NOAA Fisheries, Auke Bay Laboratories 

Additional Collaborators: 

Keri Feehan, Julia Johnstone, Maggie Halfmann, Jennifer Fields, and Ashley Rossin (University of 

Maine at Orono)

3.3 Food-web ecology and trophic ecology of red tree corals (Primnoa pacifica) in 

the eastern Gulf of Alaska

Background and Objectives: In general, the deep sea is a food-limited environment because 

only a small percentage of organic carbon produced in surface waters settles to the seafloor. In 

contrast, relative to more quiescent slope environments, deep-sea corals such as the red tree coral 

(P. pacifica), often occur in environments that experience dynamic current flow and turbulence

that influence the supply and quality of organic matter to these habitats and enhancing trophic 

complexity (Cartes and Sorbe 1999). Stable isotope analysis (SIA) is a useful method for discerning 

complex food webs, particularly in remote environments where red tree corals occur. Stable 

carbon isotopes (δ13C) closely reflect a consumer’s food source (Peterson and Fry 1987), while 

stable nitrogen isotopes have been used to estimate trophic level, because δ15N values typically 

increase 2–5 ‰ with each trophic level (Minagawa and Wada 1984, Post 2002, McCutchan et al. 

2003). Primary producers exhibit distinct isotopic compositions due to the types of nutrients fixed 

and the associated photosynthetic pathways (Peterson and Fry 1987) and isotopes integrate over 

an extended time frame, recording the assimilated diet of the consumer of long time scales. SIA 

have been used to understand transfer of carbon through systems, including tracing its vertical 

transport from the sea surface to the seafloor. In addition, SIA can help estimate food-chain 

length, trophic level, providing temporally and spatially integrated trophic estimates used to 

understand and define trophic linkages among species and communities (Davenport and Bax 

2002, Harvey et al. 2002). Our objective was to use stable carbon and nitrogen isotope analysis to 

discern primary carbon sources and estimate the trophic level for suspension feeding red tree 

corals.

Approach: Sub-samples of red tree corals collected in 2013 and 2015 with ROVs for the genetics 

and reproduction studies were used to study food-web dynamics and trophic ecology. Stable 

carbon and nitrogen isotope analysis was used to track the trophic transfer of energy from the 
23

primary producers to the corals which reside at intermediate trophic levels. These data will allow 

us to track changes in upstream nutrient conditions and productivity through examining the 

corals occurring downstream (deep sea) fueled by raining surface production on a regional level. 

We will also perform compound specific stable isotope analysis to further define and identify the 

food resources for these corals and whether they feed on primary producers that may be affected 

by ocean acidification. 

Significant Results to Date: Red tree coral tissue and associated water samples were collected 

from three study sites (Site 1 – Dixon Entrance, Site 3 – Shutter Ridge, and Site 4 – Fairweather 

Ground). Estimated trophic levels for all coral samples at Site 3 (2013) are approximately 1.5 to 3 

trophic levels above the measured particulate organic matter (POM) suggesting potential

mixotrophy (i.e. both autotrophic and heterotrophic; Figure 16). These data indicate that the 

corals could be consuming both POM and zooplankton, which in general is consistent with the 

published literature. Interestingly, the POM collected in water samples directly above the corals

was well depleted in 13C relative to the corals, so it is also possible that there is some seasonality in 

the POM source, which can lead to isotopic differences between present POM and past (what the 

corals consumed).

Funding: Collection of the samples was supported with DSCRTP (Alaska 3-year Initiative) funds 

as part of Project 1 in 2013 and 2015. Salary and benefits costs of the principal investigator (A. 

Demopoulos) and laboratory support were an in-kind contribution by the USGS (Wetland & 

Aquatic Research Center).

Points of Contact:

Amanda Demopoulos (ademopoulos@usgs.gov), US Geological Survey (USGS), Wetland & 

Aquatic Research Center, Gainesville, FL. 

Robert Stone (bob.stone@noaa.gov), NOAA Fisheries, Auke Bay Laboratory

Cheryl Morrison (cmorrison@usgs.gov), US Geological Survey (USGS), Leetown Science Center
24

Figure 16. Relationship of δ13N and δ13C raw data (A) and average values (B) for red tree corals collected at Site 

3 (Shutter Ridge) in the eastern Gulf of Alaska in 2013 and the particulate organic matter (POM) collected at 

the same collection sites. O1-O4 are coral tissue samples and POM01-POM03 are the POM samples. The

estimated trophic level arrow indicates that all coral samples are approximately 1.5 to 3 trophic levels above 

the measured POM.

2.0

4.0

6.0

8.0

10.0

12.0

-25.0 -23.0 -21.0 -19.0

δ15N (‰)

δ13C (‰)

Ommaney 1

Ommaney 2

Ommaney 3

Ommaney 4

POM-O1

POM-O2

POM-O3

avg-O1

avg-O2

avg-O3

avg-O4

Primnoa

POM

Arrow=1 trophic 

level

2.0

4.0

6.0

8.0

10.0

12.0

-25.0 -24.0 -23.0 -22.0 -21.0 -20.0 -19.0 -18.0

δ15N (‰)

δ13C (‰)

POM-O1

POM-O2

POM-O3

avg-O1

avg-O2

avg-O3

avg-O4

Primnoa

B.

Arrow = 1 trophic

level
25

3.4. Geological substrate mapping and bathymetry and sediment compilations 

Background and Objectives: Five disparate sites in The Gulf of Alaska were selected for the 

assessment of sponge and corals in regard to substrate types. These sites were located near

Chirikof Island, on Fairweather Ground, on Shutter Ridge, near Prince of Wales Island, and near 

Dixon Entrance (Figure 2). One of the primary informational tools for identifying potential 

locations of deep-sea coral and sponge ecosystems is seafloor substrate maps. In some parts of 

Alaska and in other regions these maps have been constructed using newly available multibeam 

echosounder (MBES) backscatter and bathymetry, as well as NOS bathymetry and sediment data 

from historical charting activities. The objective of this phase of work was to interpret the geology 

from the MBES data and select the most promising hard substrate locations for observation and 

sampling of deep-sea coral and sponges. 

A second objective of this project was to fund research to acquire existing bathymetry and 

sediment data available from NOS smooth sheets, digitize, correct the spatial projections and 

compile these into contiguous maps of the seafloor for the central Gulf of Alaska and Aleutian 

Islands. 

Approach: Using habitat maps constructed for the Alaska Department of Fish and Game for 

Albatross Bank, Portlock Bank, Fairweather Ground, Cape Ommaney, Cape Felix, and Learmonth 

Bank extended the substrate types from these sites into the five sites selected for sampling based 

on backscatter and bathymetry of newly collected and previously uninterpreted MBES and NOAA 

compiled data sets. Hard substrate locations at each of the five sites were selected for examination 

and sampling using a remotely operated vehicle (ROV).

The approach for bathymetry and sediment data compilation is outlined in Zimmermann and 

Benson (2013). Briefly, existing charting data was downloaded from NGDS and other sources. Data 

were digitized and overlapping bathymetries hand checked for errors and agreement. Data were 

compiled to a common projection. The sediment data was compiled using the same approach.

Significant Results to Date: 

Interpretation of newly collected MBES and compiled NOAA data sets provided targets for ROV 

dives in locations where hard or mixed soft over hard substrate appeared to be present. Several 

locations were picked at each of the five sites as explained below:

Chirikof – five locations where hard or mixed substrate appeared to be present were selected and 

consist of possible bedrock or hard mud bottom in interfluve (ridges separating slope gullies, “1” 

in Figure 17) and boulders associated with drop stones at the front of a former ice front (“2” in 

Figure 17). This site is located seaward of a past glacial front and contains extensive glacial 

sediment. Fairweather Ground – six locations where hard substrate appeared to be present, four 

in locations where high relief, rugged bedrock crops out on the continental shelf floor and along 

the ridge of an interflu on the continental slope (“1” in Figure 18), and two along the upper walls of 

submarine canyons or gullies (“2” in Figure 18) on the upper continental slope. This site is not 

glaciated but consists of local areas of glacial deposition. Cape Ommaney – two potential hard 

substrate locations were selected for sampling and are denoted in dark green polygons along the 

western edge of Figure 19, a potential marine benthic habitat map. The primary site known as 

“Shutter Ridge” consist of hard fractured and jointed plutonic (granite) basement rock outcrop on 

the continental shelf and shown as a N-S elongated green polygon along the SW edge of Figure 19. 
26

This is an area that has been locally affected by glaciation. Prince of Wales – eight potential hard 

to soft to hard substrate locations were selected for sampling and consist of possibly five hard 

bedrock outcrops in gully walls and a fault scarp on the upper continental slope and mixed soft 

covered isolated large boulders or bedrock outcrops on the continental shelf (“1” in Figure 20). 

Two linear subtle scarps with rugged (possibly boulders) relief near the distal edge of the 

continental shelf and one isolated boulder or sediment covered bedrock outcrop (“2” in Figure 20) 

were selected for sampling. This is a heavily glaciated area with moraines and an extensive drop 

stone field. Dixon Entrance – seven locations that appear to consist of hard or soft over hard 

substrate were selected for sampling. Two locations where hard substrate appears to be present 

along a fault scarp and rock outcrops or large boulders exist in high relief on the continental shelf 

were selected for sampling (“1” in Figure 21). Three locations consisting of soft over hard substrate 

types, one in a small boulder field on the continental shelf and two on the upper slope were 

selected for sampling (“2” in Figure 21). Two other locations were selected in deeper water and 

consist of poorly defined relatively high relief features (“3” in Figure 21) in a generally subtle 

hummocky to flat seafloor. The site represents a glaciated area on the continental shelf with 

extensive deposition of glacial material over the continental slope. 

Funding from the DSCRTP partially supported the efforts of AFSC scientists as they proofed, 

corrected, and digitized 1.75 million lead-line and single-beam echosounder soundings from 225 

National Ocean Service (NOS) hydrographic surveys represented as smooth sheets in the central 

Gulf of Alaska. This bathymetry compilation ranged geographically from the Trinity Islands in the 

west to Cape Ommaney in the east, covering an arc of about 1,400 km of shelf. The bathymetry 

maps were compiled for an area of the central Gulf of Alaska near Prince William Sound. In the 

Aleutian Islands, AFSC scientists also digitized 25,000 verbal surficial sediment descriptions from 

234 of the smooth sheets, providing the largest single source of sediment information. Scientists 

from the USGS proofed and digitized ~117K verbal surficial sediment descriptions from the 225 

NOS hydrographic surveys represented as smooth sheets in the central Gulf of Alaska (Golden et 

al. 2016). These bathymetry and sediment layers were a critical data set for coral and sponge 

distribution modeling (Rooper et al. in review).

Funding: Geological substrate verification for this project was completed during the Primnoa 

thickets study in the eastern Gulf of Alaska. Grants and contracts to UAF and UC Davis for 

geological substrate interpretation, fieldwork and coordination ($91,355) were funded in FY12-14. 

Funding to support technicians for sediment and bathymetry compilation ($67,160) was also used 

in FY12-14. 

Points of Contact: 

Jennifer Reynolds, University of Alaska Fairbanks (jrreynolds@uaf.edu), H. Gary Greene, Tombolo 

Institute (greene@mlml.calstate.edu), Robert Stone (bob.stone@noaa.gov), Mark Zimmermann 

(mark.zimmerman@noaa.gov), Jane Reid, USGS, (jareid@usgs.gov)
27

Figure 17. Multibeam bathymetric images of the Chirikof dive site selected for ROV examination and sampling 

of deep-water corals and sponges. Red outlines indicate interesting geological features identified for further 

exploration with underwater cameras or remote operated vehicles. 

Figure 18. Multibeam bathymetric images of the Fairweather Ground dive site selected for ROV examination 

and sampling of deep-water corals and sponges. Red outlines indicate interesting geological features identified 

for further exploration with underwater cameras or remote operated vehicles.
28

Figure 19. Marine benthic habitat map of the Cape Ommaney dive site selected for ROV examination and 

sampling of deep-water corals and sponges.
29

Figure 20. Multibeam bathymetric images of the Prince of Wales dive site selected for ROV examination and 

sampling of deep-water corals and sponges. Red outlines indicate interesting geological features identified for 

further exploration with underwater cameras or remote operated vehicles.

Figure 21. Multibeam bathymetric images of the Dixon Entrance dive site selected for ROV examination and 

sampling of deep-water corals and sponges. Red outlines indicate interesting geological features identified for 

further exploration with underwater cameras or remote operated vehicles.
30

3.5. Recovery, ages and growth rates of Primnoa pacifica in the Gulf of Alaska 

Background and Objectives: Red tree corals (Primnoa pacifica) are common bycatch items in 

fisheries for demersal species and in stock assessment surveys in Alaska (Heifetz et al. 2005). 

Primnoa colonies have a large size and arborescent growth pattern that make them highly 

susceptible to disturbance from fishing activities (Stone et al. 2014). Primnoa pacifica populations 

are presumably slow to recover from such disturbance, because large corals are estimated 100+ 

years old (Andrews et al. 2002, Williams et al. 2007). The importance and vulnerability of red tree 

coral thickets has been recognized by the North Pacific Fishery Management Council and some 

protection has been afforded to known thickets in the region (Stone and Shotwell 2007). The 

Alaska Essential Fish Habitat Research Plan identifies recovery rate information for deep-sea 

corals as a high priority for research in Alaska (Sigler et al. 2012). The plan states that few recovery 

rate studies have been proposed, yet the information is critical for assessing the effects of fishing 

on vulnerable habitat.

A better understanding of population demographics in P. pacifica populations is needed in order 

to estimate recovery rates under various disturbance scenarios. Size class structure, rates of 

growth, rates of injury and mortality, size at maturity, and recruitment rates are all important 

parameters for understanding the vulnerability of populations and their potential for recovery.

This study focuses on size-class structure as a non-invasive means of estimating colony age and 

maturity. The report is combined with another DSCRTP project funded through the National 

Undersea Research Program (NURP) “Ages, Growth Rates, and Climate Reconstructions from 

Deep-Sea Primnoidae Corals” (B. Williams and P. Etnoyer co-PIs).

Primnoa pacifica corals are good subjects of study because their age and growth rate can be 

determined using lead and radiocarbon dating of growth rings visible in cross-sections of the base 

of the colony (Andrews et al. 2002, Aranha et al. 2013). Assuming that age positively correlates to 

vertical and basal radial size, colony height, width, and basal diameter of the holdfast reflect 

population age-structure. Therefore, the age of deep-sea Primnoa corals can be estimated from 

scaled in-situ images. The objective in this study was to establish a baseline for the size class 

distribution on P. pacifica corals on Shutter Ridge and to correlate this with age to infer their age 

class structure.

Approach: Coral observations from three surveys of Shutter Ridge were included in this analysis: 

stereo drop-camera surveys in August 2013 (Table 2). HOV Delta submersible survey in August

2005 (Table 3, Stone et al. 2014); and remotely operated vehicle surveys during August 2013 (Table 

4). Stereo-frame images were collected from a stereo drop-camera sled system towed or drifted 

continuously along linear transects at, or near the seafloor, collecting 17,461 stereo photo-frames 

(Table 2). Delta submersible surveys produced approximately 12 hours of benthic video footage 

within Shutter Ridge from 10 strip transects (Stone et al. 2014). The 2013 ROV survey of Shutter 

Ridge resulted in 15 hours of video footage.

Shutter Ridge is a deep-water geologic feature, in which elongated fault-line ridge rises

dramatically on one side, but gently slopes on the opposite side (Greene et al. 2011). The base of 

the feature lies at 270 m depth, and it reaches 61 m at its highest summit. Several peaks near 150 m 

depth are notable within the 10 km long ridge (Figure 22), with many areas of exposed rock. The 

ridge lies ~26 km from Cape Ommaney and the southernmost point of Baranof Island in 

Southeastern Alaska’s continental shelf. 
31

Table 2. List of 2013 stereo drop camera hauls in Shutter Ridge feature.

Table 3. List of ROV Dives in Eastern Gulf of Alaska shelf feature in 2013.

Table 4. List of dives in the Shutter Ridge feature by the Delta manned submersible.

Stereo frames were enumerated and sized for coral observations using Sebastes 1.3 software 

(Williams et al. 2016). A screenshot of the size analysis method is shown in Figure 23. 

Corals in submersible and ROV images were assessed using software Image-J with lasers to 

calibrate size. Colony counts and size estimates used downward-looking cameras with 20 cm 

lasers, and forward-looking cameras with 10 cm lasers. Data were binned into five size categories: 

10-49 cm; 50-99 cm; 100-149 cm; 150- 199 cm; and 200 + cm. Primnoa pacifica colonies of 

indeterminate size were counted, but not used for size estimation

A total of fifteen whole colony biological samples of various sizes were collected by ROV during 

three surveys from 2013 to 2015 (Table 5). Each colony was measured for five morphometric 

variables (height, width, basal diameter, linear distance to first branch point and mass) wet

weight, and dry weight. Three ~ 0.5 cm thick cross-sectional disks were removed from the base, 

middle, and top portion of specimens 1-3 (Table 5) for radiocarbon analysis.

Locality Dive Type Date EventID Haul Duration Start 

Latitude

Start 

Longitude

End 

Latitude

End 

Longitude

On 

Bottom 

Frames

Max 

Depth

Total 

Frames

Shutter Ridge Drop Cam 8/14/2013 13-226D 1abc 1:21:00 56.1783 -135.1166 56.1798 -135.1151 170 222.1 1384

Shutter Ridge Drop Cam 8/14/2013 na 2a na na na na na na 202.2 0

Shutter Ridge Drop Cam 8/14/2013 13-226E 3a 0:08:00 56.1782 -135.1164 56.1788 -135.1198 122 222.9 459

Shutter Ridge Drop Cam 8/14/2013 13-226F 4ab 0:44:00 56.1785 -135.1146 56.1798 -135.1208 238 224.1 1510

Shutter Ridge Drop Cam 8/14/2013 13-226G 5a 0:45:00 56.1565 -135.1222 56.1595 -135.1187 239 246 2267

Shutter Ridge Drop Cam 8/14/2013 13-226H 6a 0:29:00 56.1716 -135.1172 56.1669 -135.1193 112 225.8 1652

Shutter Ridge Drop Cam 8/14/2013 13-226I 7a 1:27:00 56.2079 -135.1039 56.1959 -135.1082 102 172.2 4961

Locality Dive Type EventID Dive Date Start Time End Time Start 

Latitude

Start 

Longitude

End 

Latitude

End 

Longitude

Min 

Depth

Max 

Depth

Shutter Ridge ROV 13-226A 8/14/2013 10:46:00 13:25:00 56.1725 -135.1360 56.1754 -135.1170 185 225

Shutter Ridge ROV 13-226B 8/14/2013 16:18:00 18:51:00 56.1801 -135.1200 56.1777 -135.1180 196 218

Shutter Ridge ROV 13-227A 8/15/2013 9:34:00 12:31:00 56.1972 -135.1011 56.1967 -135.1020 110 184

Shutter Ridge ROV 13-227B 8/15/2013 16:15:00 19:31:00 56.1808 135.1194 56.1970 -135.1017 201 246

Shutter Ridge ROV 13-228A 8/16/2013 9:14:00 12:35:00 56.1967 -135.1020 56.1979 -135.1020 71 114

Shutter Ridge ROV 13-228B 8/16/2013 16:05:00 19:17:00 56.1783 -135.1184 56.1785 -135.1190 204 231

Locality Dive Type Dive Date EventID Transects Start Time End Time Start 

Latitude

Start 

Longitude

End 

Latitude

End 

Longitude

Min 

Depth

Max 

Depth

Shutter Ridge Delta Sub 2005-08-20 05-232B OM1; OM2 10:40:20 11:49:09 56.1707 -135.1056 56.6372 -135.0969 203 254

Shutter Ridge Delta Sub 2005-08-19 05-231C OM3; OM4 15:23:35 17:20:05 56.1702 -135.1088 56.1878 -135.1154 192 244

Shutter Ridge Delta Sub 2005-08-20 05-232A OM5 8:18:24 9:48:58 56.1878 -135.1154 56.1779 -135.1007 181 218

Shutter Ridge Delta Sub 2005-08-17 05-229C OM6 16:57:16 13:43:35 56.1880 -135.1176 56.1843 -135.1014 81 209

Shutter Ridge Delta Sub 2005-08-19 05-231A OM7 8:00:05 9:17:56 56.1893 -135.0938 56.1954 -135.1115 144 193

Shutter Ridge Delta Sub 2005-08-17 05-229A OM8 11:35:18 12:55:21 56.1949 -135.1084 56.1986 -135.0909 69 175

Shutter Ridge Delta Sub 2005-08-17 05-229B OM9 13:51:35 14:39:38 56.2005 -135.0944 56.2063 -135.1101 158 178

Shutter Ridge Delta Sub 2005-08-19 05-231B OM10 10:07:03 10:59:52 56.2133 -135.1065 56.2049 -135.0921 109 171
32

Figure 22. Depth-profile of Shutter Ridge (top, from NNE to SSW), plan view (inset left, red is shallow), and 

perspective view (bottom, yellow is shallow).

Figure 23. In situ stereo images showing the method for estimating Primnoa pacifica colony sizes using 

Sebastes 1.3 software (Williams et al. 2016). Euclidean triangulation is used to estimate distance based on the 

comparison between six measured values in two calibrated cameras mounted on a sled.
33

The disks were acidified in 5% HCl for one week with daily acid changes to ensure full dissolution 

of the calcite skeleton. Next, the samples were thoroughly washed with Milli-Q water and 

maintained wet in a Milli-Q bath. Under light microscope, growth rings were peeled away from 

each disk using forceps to work from the outside of the disk toward the inside. Growth rings from 

the center of each disk and the middle and outside of the basal disk (n = 5 per colony) were 

isolated, dried at room temperature overnight, and prepared for Accelerated Mass Spectrometer 

dating at the University of California Irvine.

Table 5. List of Primnoa pacifica colony samples obtained during surveys from 2013 to 2015. Specimens were 

collected from the 2013 AFSC bottom trawl survey (AK Vessel 143), the 2013 ROV survey (AK Provider) or the 

2015 ROV survey (Dorado Discovery). Specimens were measured for seven variables. Ring count measures are 

in progress across the basal cross-sections for all specimens, and initial radiocarbon values are available from 

three of the specimens.

Significant results to date: The total number of P. pacifica colonies observed on surveys of 

Shutter Ridge between 2005 and 2013 was n = 5,501. Colonies were observed with a depth range of 

127 to 245 m. They were absent from the depth range 60-126 m. The mean depth for Primnoa

observations on Shutter Ridge was 176 m, and the median 167 m. The mean depth for survey effort 

was 156 m. High densities of large colonies were observed (> 1 colony*m-2

). 

In total, 1,020 in situ size estimates were made for P. pacifica colonies (Figure 24). Nearly 70% of 

colonies were larger than 1 m, and 10% were larger than 2 m (Figure 24). Colony size was 

correlated with depth. The largest colonies were deep and smallest ones were shallow (Figure 25). 

The largest P. pacifica colonies (> 2 m) were present near the base and surrounding perimeter of 

the Shutter Ridge at 200 m depth. Highest abundance of colonies was between 200 and 220 m 

depth. Most colonies were 0.5 to 1.5 m tall. 

Sample Collection 

Date Vessel Locality Event Latitude Longitude Depth 

(m)

Height 

(cm)

Width 

(cm)

BaseD 

(mm)

1st Branch 

dist. (cm)

Mass 

(Kg)

Dry Mass 

(Kg)

GOA 004 07/19/2013 FV Sea Storm Nula Bay Trawl Haul 224 59.3545 -150.5277 290 78 50 15.0 16.0 1.08 0.65

GOA 005 07/26/2013 FV Sea Storm Middleton Ridge Trawl Haul 252 59.6652 -143.2214 248 79 32 13.0 28.0 1.28 na

GOA 003 08/04/2013 FV Sea Storm Dixon Entrance Trawl Haul 290 54.5747 -132.9844 398 64 22 12.5 9.0 0.40 0.23

GOA 011 08/13/2013 FV AK Provider Shutter Ridge ROV Dive 10 56.1749 -135.1165 191 65 24 10.0 8.5 0.62 na

GOA 022 08/14/2013 FV AK Provider Shutter Ridge ROV Dive 11 56.1722 -135.1160 203 72 32 16.0 12.3 1.13 na

GOA 012 08/15/2013 FV AK Provider Shutter Ridge ROV Dive 12 56.1921 -135.1103 165 58 39 13.0 13.0 0.77 na

GOA 060 08/15/2013 FV AK Provider Shutter Ridge ROV Dive 13 56.1785 -135.1180 203 123 44 25.0 32.0 2.13 0.91

GOA 067 08/16/2013 FV AK Provider Shutter Ridge ROV Dive 15 56.1784 -135.1180 214 153 121 45.0 32.0 na 2.13

WPA 001 06/04/2015 Dorado Discovery Fairweather Grd ROV Dive 04 58.2457 -138.9045 141 123 67 32.5 7.0 2.24 0.96

WPA 002 06/04/2015 Dorado Discovery Fairweather Grd ROV Dive 04 58.2458 -138.9044 142 171 60 25.5 62.0 1.25 0.51

WPA 003 06/05/2015 Dorado Discovery Fairweather Grd ROV Dive 05 58.2377 -138.9894 147 110 70 24.0 30.0 na na

WPA 004 06/06/2015 Dorado Discovery Fairweather Grd ROV Dive 08 58.2047 -138.8175 163 223 101 53.0 29.5 20.45 7.27

WPB 005 06/08/2015 Dorado Discovery Dixon Entrance ROV Dive 12 54.6252 -132.8828 335 160 98 49.0 29.0 16.60 na

WPB 006 06/08/2015 Dorado Discovery Dixon Entrance ROV Dive 13 54.6345 -132.8510 164 99 26 19.0 20.0 1.14 na

WPB 007 06/08/2015 Dorado Discovery Dixon Entrance ROV Dive 13 54.6345 -132.8510 164 87 23 15.0 17.0 0.64 na
34

Figure 24. Size distribution (m size categories) of observed Primnoa pacifica colonies in Shutter Ridge. A total 

of 1,020 colonies were measured.

Radio-isotope aging of the colonies showed the radiocarbon content decreasing from the oldest 

part of the skeleton to the youngest part of the skeleton of all three colonies in both the radial and 

vertical directions. This suggests that coral growth could have started after thermonuclear bombtesting peaked in the mid-1970s. Thus the corals are recording the decline in atmospheric 

concentrations of the “bomb” carbon. However, based on the sizes of the coral colonies and 

growth rates from Primnoa sp from other locations, it is likely that these corals exceed several 

decades in age. Thus, the declining radiocarbon content toward the present could also indicate 

increased contributions of old carbon, either via increased upwelling and/or increased 

contribution of terrestrial carbon. 

Radiocarbon values (reported as Δ14C) ranged from -16.5 to 25.3 ‰ over the lifespan of the three 

corals (Figure 26). Particularly in specimens GOA 011 and GOA 0 22, the Δ14C indicate 

contributions of “old” 14C that dilutes the anthropogenic “bomb” carbon signature. This carbon 

could be carbon upwelled from below the surface mixed layer or terrestrial-derived carbon 

entering the ocean via rivers or glacial melt.

The majority of colonies measured in this study (900/1,020 = 88%) were of a mature height (> 42 

cm, Waller et al. 2014). The population appears to be a viable, and potential source of larvae to 

other habitats. The estimated time to recovery is at least 100 years, give the size of the largest 

colonies. Radiocarbon and 210Pb data suggest that the largest colonies are over 100 years old but 

the average size colonies (0.5-1.5 m) tall may be closer to 50-60 years old. 
35

Figure 25. Distribution of Primnoa pacifica colony sizes. Black triangles represent survey tracks. The largest 

Primnoa pacifica colonies were generally observed in the deep rocky portion of the Shutter Ridge. They were 

absent from areas shallower than 100 m.

210Pb dating is in progress to verify the ages of the corals as to whether their lifespans pre-date 

peak “bomb” carbon concentrations. This information will either validate the radiocarbon growth 

estimates and the fast rates of growth of these corals or indicate that contributions of old carbon 

are confounding radiocarbon dating at this location. Regardless, the wide variability in 

radiocarbon recorded by the different corals in most recently formed skeleton suggests a 

heterogenic radiocarbon content of the water and organic matter. This supports the latter 

hypothesis of old carbon contributing to the radiocarbon signature at this location. 
36

Radial ring counts are also in progress, which will be used with the 210Pb-derived dates to 

determine growth ring periodicity. Principal component analysis will determine components 

correlated to radial and linear growth and biomass.

Figure 26. Radiocarbon results for three Primnoa pacifica colonies. Δ14C values were measured across a basal 

cross-section (top) and a linear transect (bottom) for each specimen. 

Future surveys should recursively target small-scale features (200-500 m), in order to verify 

absence of P. pacifica from shallow depths and to gain understanding of P. pacifica patch-size and 

the fine-scale influence of aspect, bottom currents, turbulence, and resource availability. More 

information on settlement rates, gender ratio and fecundity of the population would help to 

quantify birth and immigration. More information on fishing intensity, fishing-induced mortality, 

and natural predation would be helpful to quantify death and emigration. The sum of this 

information would allow new types of population dynamic studies and state-and-transition 

-15

-10

-5

0

5

10

15

20

25

30

0 10 20 30 40 50

Δ14C (0/00)

Radial distance from center of basal cross-section (mm)

GOA 004

GOA 22

GOA 011

-25

-20

-15

-10

-5

0

5

10

15

20

25

30

0 20 40 60

Δ14C (0/00)

Distance from Base (cm)

GOA 004

GOA 22

GOA 011
37

models to define tipping points and thresholds in a changing deep ocean environment under 

pressure from commercial fisheries.

Funding: Collection of samples for this project was completed during the Primnoa thickets study 

in the eastern Gulf of Alaska. Funding for image analysis and travel to the fieldwork ($100K total) 

were provided by the Alaska Initiative. Additional funding for analysis of size structure data was 

provided by the AFSC HEPR program through a successful proposal ($52,500). 

Points of contact: 

Peter Etnoyer, NOAA National Ocean Service, National Centers for Coastal Ocean Science, Peter 

Etnoyer, peter.etnoyer@noaa.gov, 

Branwen Williams, Keck Science Department at Claremont, Pitzer, Scripps Colleges, 

BWilliams@kecksci.claremont.edu

3.6. Distribution models for eastern Bering Sea, Gulf of Alaska and Aleutian 

Islands deep-sea coral and sponge

Background and Objectives: Deep sea coral and sponge ecosystems are widespread throughout 

most of Alaska’s marine waters. In some places, such as the western Aleutian Islands, these may 

be among the most abundant cold-water coral and sponge communities in the world. Because of 

the size and scope of Alaska’s continental shelf and slope, the vast majority of the area has not 

been surveyed for the presence of coral and sponge communities. Since the spatial distribution of 

these communities is not known in Alaska, it is difficult to predict the locations and types of 

human activities that may be threats to the deep-sea coral and sponge ecosystems. The objectives 

of this project were to predict the distribution of coral and sponge ecosystems for the eastern 

Bering Sea, Gulf of Alaska and Aleutian Islands.

Approach: Historical bottom trawl surveys conducted by the RACE Division have collected data 

on the presence and abundance of corals and sponges in all areas of Alaska. We used data from 

1996-2012 biennial bottom trawl surveys to examine the distribution and abundance of coral and 

sponge ecosystems. Generalized additive models based on the location (latitude and longitude), 

depth, slope, sediment, ocean current, bottom temperature and ocean color were used to predict 

the probability of presence of sponges corals and sea whips. 

Significant results to date: In the eastern Bering Sea about 61% of coral habitat was predicted to 

occur in slope areas (39% was predicted to occur on the outer shelf of the eastern Bering Sea; 

Figure 27). Of the slope areas, the highest amount of coral habitat was predicted to occur in 

Pribilof Canyon (33% of the predicted coral habitat occurs here). Only 1% of coral habitat was 

predicted for Zhemchug Canyon and the rest occurred primarily in the Pribilof-Zhemchug intercanyon area, in the Zhemchug-Pervenets inter-canyon area and in Navarin Canyon. This implies 

that about one third of the coral habitat predicted for the eastern Bering Sea occurs in Pribilof 

Canyon, an area that comprises only about 10% of the total slope area. In contrast, about twothirds of sponge (64%) and most sea whip (91%) habitat was predicted to occur on the outer shelf, 

an area that comprises about 82% of the total area of the slope and shelf examined. These results 

and analyses were published in Sigler et al. (2015) and validated in Rooper et al. (2016).
38

Figure 27. Predicted probability of presence or absence of coral, sponges and sea whips and sea pens from a 

generalized additive model (Sigler et al. 2015).

In the Aleutian Islands the most important factors in determining coral presence or absence and 

abundance were location, maximum tidal current and slope. For sponges the most important 

factors determining presence or absence and abundance were location, maximum tidal current 

and depth. Coral and sponge were predicted to occur in relatively high abundance throughout the 

Aleutian Islands, but particularly in the areas surrounding Seguam Pass, Petrel Bank, and the area 

just to the east of Kiska Island (Figure 28). In the Gulf of Alaska corals and sponges are predicted 

to occur primarily along the shelf break and in hard-bottom areas of the Gulf, while sea pens and 

whips occur in large areas of the continental shelf (Figure 28).

Funding: This project used existing data and required no funding from the DSCRTP. In kind 

contributions of time for the principal investigator was the only requirement.

Point of Contact: Chris Rooper, AFSC-RACE Division, chris.rooper@noaa.gov

Coral Sponge Sea whips and 

pens
39

Figure 28. Predictions of the best-fitting generalized additive model for sponge, coral, Primnoidae, and 

Stylasteridae predicting the abundance (log-transformed catch-per-unit-of-effort (CPUE) or CPUE) in the 

Aleutian Islands (left) and pennatulaceans, corals and sponges in the Gulf of Alaska (right) bottom trawl 

surveys (Rooper et al. 2014, Rooper et al. in review).

3.7. Longline Impacts study

Background and Objectives: Disturbance from longline fishing to sensitive coral and sponge 

habitats has been documented in Alaska but the extent of and mechanisms of disturbance have 

not been well studied compared to bottom trawling. Observations in red tree coral thickets in the 

eastern Gulf of Alaska indicate that 17% and 20% of the “standing stock” of corals and sponges, 

respectively, have been damaged by longlines (Stone et al. 2014). Corals and sponges are common 

bycatch in both commercial fisheries and stock assessment surveys using longlines clearly 

indicating interactions between the gear and sensitive habitats. Bycatch of branching corals is 

generally higher than that of sponges, presumably due to differences in how easily they can 

become entangled in the gear. The goal of this project was to examine the behavior of longline 

gear in situ during all stages of fishing. 

Approach: This pilot project used two tools to examine longline disturbance of benthic habitat. 

The first tool was a camera system was developed that took intermittent pictures of the seafloor 

during all stages of the set (deployment, on-bottom fishing and retrieval). The second tool was a 

series of accelerometers that were attached to the longline ground gear. Both tools were deployed 

on a longline survey vessel that was conducting stock assessment surveys in 2013 and 2014. The 

camera system was deployed in both years, while the accelerometers were deployed in 2014 only.
40

Significant results to date: Analyses of the images collected in 2013 did not indicate that the 

groundline of the longline moved along the seafloor during deployment. There were only two 

successful tests of the camera system that year, and in both cases the camera was stationary 

throughout the 6 hour set. Both deployments were conducted in sandy benthic habitat. 

In 2014, 12 camera deployments were conducted. Image analyses for these deployments are still 

underway. The accelerometers were deployed on 12 longline sets in six locations along the 

longline in 2014. The accelerometer data are very noisy (Figure 29), and some Kalman filtering is 

necessary to analyze the data. For most cases, the data indicates minimal if any movement of the 

longline during setting, fishing and recovery. However, there were a few cases where there was 

some indication of increased acceleration during the set that could have indicated the longline 

was traveling across the seafloor. These results are very preliminary and analyses are still ongoing 

with this data. 

Funding: Vessel time and personnel time were contributed in kind by the AFSC and the annual 

longline survey. The DSCRTP contributed ($18,125) for the purchase of underwater equipment and 

travel to and from the field locations in FY13 and FY14.

Point of contact: Chris Rooper, AFSC-RACE Division, chris.rooper@noaa.gov
41

Figure 29. Example accelerometer data (acceleration, velocity, and distance in x, y and z directions) for two deployments on longline gear. The left hand 

deployment shows a probable movement of the longline gear during the middle of the deployment, while the right hand deployment shows a stationary 

deployment.
42

3.8. Genetic connectivity among offshore and emergent fjord-populations of red 

tree corals (Primnoa pacifica) in the Gulf of Alaska

Background and Objectives: Knowledge of the degree to which spatially discrete marine 

populations of sedentary fauna are connected through larval dispersal is important for effective 

resource management. Red tree corals (P. pacifica) are the dominant structure forming coral on 

the outer continental shelf and upper slope between the Alaska Peninsula and the Olympic Coast 

Marine Sanctuary off the Washington Coast yet little is known about their larval dispersal 

capability or population connectivity. Red tree corals provide important habitat for fishes and 

invertebrates and are long-lived animals highly susceptible to disturbance from human activities

including interaction with fishing gear. Accordingly, some protection has been afforded to several 

offshore populations through the establishment of Habitat Areas of Particular Concern where all 

fishing activities are now prohibited. The closures were established however without any 

knowledge of how these populations may be connected genetically. Red tree corals are also a 

dominant component of emergent fjord communities in Southeast Alaska, occurring in depths as 

shallow as six meters. The complex combination of extreme tides, strong seasonal storms, 

freshwater discharge, and intricate passageways to the open ocean may restrict larval exchange 

between offshore and fjord populations, or conversely, fjord populations could become important 

larval sources should offshore populations become depleted.

The objective of this study was to examine the genetic connectivity of “distinct” red tree coral 

populations in the eastern Gulf of Alaska. This study builds on ongoing work using microsatellite 

DNA markers to generate data on the spatial scale and pattern of genetic connectivity across a 

large portion of the range of red tree corals in the North Pacific Ocean. These data will provide 

important insights regarding the most appropriate tools available to resource managers to protect 

sensitive coral habitats and the ecosystem services they provide. Using population genetic data for 

a North Pacific Ocean coral species for the first time, will provide important insights regarding 

population sensitivity and the capability of the region’s ecologically most important coral species 

to recover from anthropogenic disturbance.

Approach: As part of an ongoing study on an emerged population of red tree corals in Tracy and 

Endicott Arms, Holkham Bay, Southeast Alaska we had completed much of the preliminary work 

developing microsatellite DNA markers for the species. We collected additional samples with a 

remotely operated vehicle (ROV) at Site 3 (Shutter Ridge) in 2013 (Figure 30, Figure 31) that 

provided for the successful develop of 12 microsatellite markers needed for this study (Morrison et 

al. 2015). Using an ROV in 2013 and 2015, we were able to collect samples from 46 colonies at Site 1 

(Dixon Entrance), 52 colonies at Site 3 (Shutter Ridge), and 53 colonies at Site 4 (Fairweather 

Ground; Figure 30). In June 2014 we chartered the Alaska Department of Fish & Game (ADF&G) 

RV Medeia and using scuba and a small ROV (Phantom XTL) collected samples from 34 colonies 

in an emerged population (depths 14–50 m) in Endicott Arm, Holkham Bay, Southeast Alaska

(Figure 30).

Significant Results to Date: Microsatellite markers were used to characterize the spatial scale 

and pattern of genetic connectivity across a large portion of the range of red tree corals in the 

eastern Gulf of Alaska. More than 240 discreet, geo-referenced samples were collected with ROVs 

and scuba from three offshore populations (Dixon Entrance, Shutter Ridge, and Fairweather 

Ground) and two emerged fjord populations (Tracy and Endicott Arms, Holkham Bay, Southeast 
43

Alaska). A complex pattern of connectivity was recovered with offshore populations being more 

highly connected than fjord populations. 

We also used next generation sequencing technology, specifically restriction site associated DNA 

(RAD), to identify and genotype 700 novel SNP (single nucleotide polymorphisms) markers for 

these same samples of red tree corals. These SNPs will allow for direct comparisons of

connectivity patterns assessed from SNP versus the microsatellite markers.

Funding: Collection of the offshore GOA samples was supported with DSCRTP (Alaska 3-year 

Initiative) funds as part of Project 1 in 2013 and 2015. DSCRTP funds were used to support the 5-

day cruise aboard the ADF&G RV Medeia in FY2014 ($20,000) and purchase laboratory supplies in 

FY2012 ($4,000), FY2013 ($3,200), and FY2014 ($3,000). An in-kind contribution by the Auke Bay 

Laboratory in FY2012 ($2,000) was used for the purchase of additional laboratory supplies. Travel, 

salary and benefits costs for the principal investigator (C. Morrison) and laboratory support were 

an in-kind contribution by the USGS (Leetown Science Center).

Points of Contact: 

Cheryl Morrison (cmorrison@usgs.gov), US Geological Survey (USGS), Leetown Science Center 

Robert Stone (bob.stone@noaa.gov), NOAA Fisheries, Auke Bay Laboratories

Meredith Everett (meredith.everett@noaa.gov), NOAA, Northwest Fisheries Science Center
44

Figure 30. Map of the eastern Gulf of Alaska showing the five study sites (Site 1, Site 3, Site 4, Tracy Arm and 

Endicott Arm) where samples were collected from red tree corals to study genetic connectivity in 2013 and 

2015. 
45

Figure 31. Collecting red tree coral samples for genetics studies with the ROV Zeus II at Site 4 (Fairweather 

Ground) in June 2015.
46

3.9. Long-term monitoring of O2 and pH in Alaska waters; a sentinel for global 

climate change and ocean acidification

Background and Objectives: The effects of global climate change and ocean acidification are 

expected to be more extreme at higher latitudes, such as in Alaska. Deep- coral and some sponge 

communities are especially susceptible to ocean acidification through reductions in calcification 

rates due to reduction in the available carbonate ions. Thus it is important to determine the rates 

of ocean acidification through monitoring pH and to determine shoaling and expansion of O2 

minimum zones in order to predict and understand the effects of climate change on deep coral 

and sponge ecosystems.

Approach: The AFSC RACE Division annually conducts stock assessment surveys in Alaska 

ecosystems aboard chartered fishing vessels. These platforms provide an opportunity for low cost 

monitoring by instrumenting the bottom trawl survey nets to collect additional environmental 

data. We purchased two Aanderra oceanographic units that have sensors that collect depth, 

temperature, salinity, turbidity, pH and O2. 

Significant Results to Date: Beginning in 2012, protocols for data collection were developed and 

the oceanographic equipment was deployed on bottom trawls in the eastern Bering Sea slope 

survey. Environmental variables were collected during 168 trawl hauls from Bering slope to the 

US-Russian border. In 2013, the environmental data was collected on 218 trawl hauls in the Gulf of 

Alaska and in 2014 data was collected on 300 trawl hauls in the Aleutian Islands. 

Oxygen concentrations were higher in shallow areas of the eastern Bering Sea slope, but there 

were also some areas of low oxygen concentration in the middle of Pribilof and Zhemchug 

canyons (Figure 32). pH distribution followed oxygen very closely. Oxygen concentration in the 

Gulf of Alaska was highest in areas to the west of the Shumagin Islands the on the middle and 

inner shelf and was uniformly low in SE Alaska (Figure 32). pH was low in a band across the shelf 

near the Shumagin Islands and generally was low on the outer shelf elsewhere in the Gulf of 

Alaska (Figure 32). pH and oxygen varied spatially in the Aleutian Islands and also changed with 

depth. Both variables exhibited lower values on underwater banks (such as Petral Bank) and 

generally the two values appeared to be correlated. The highest concentrations of oxygen and the 

highest values of pH occurred in the central Aleutian Islands. 

Environmental variables continued to be collected in 2015 and beyond. The on bottom 

environmental data is summarized annually and included in the Ecosystem Considerations 

Chapter of the Stock Assessment and Fisheries Evaluation documents provided to stock 

assessment authors and fisheries managers each year. In the future we plan to use these data to 

document changes in distribution of environmental conditions and model the effects on the 

distribution of deep-sea coral and sponge ecosystems.

Funding: Funding was provided by the DSCRTP to purchase two CTDs ($58,816) in FY12 and for 

calibration and modification in FY14 ($12,140).

Point of contact: Chris Rooper, AFSC-RACE Division, chris.rooper@noaa.gov
47

Figure 32. Maps of summer distribution of seafloor O2 (left panel) and pH (right panel) during trawl surveys of 

eastern Bering Sea slope (2012), Gulf of Alaska (2013), and Aleutian Islands (2014).
48

3.10. Long-term monitoring of oceanographic conditions in Southeast Alaska

Background and Objectives: There are few long-term oceanographic stations in the Gulf of 

Alaska and no sub-tidal stations in the eastern Gulf of Alaska where red tree corals (P. pacifica) 

form dense thickets on the continental shelf and in shallow waters of glacial fjords. Long-term 

oceanographic data are of paramount importance to study the pending effects of ocean warming 

and acidification on the coral resources of Alaska. 

Access with scuba diving to red tree corals that have emerged into shallow water in several glacial 

fjords of Southeast Alaska have been studied year-round since 2004. These coral populations may 

prove to be sentinel populations for studies on the effects of global climate change and ocean 

acidification on marine processes in the North Pacific Ocean. This project was designed to

establish a long-term oceanographic station in Tracy Arm, Holkham Bay, Southeast Alaska were 

studies on the biology and genetics of red tree corals have been ongoing since 2006.

Approach: In 2012 we purchased an oceanographic array from SAtlantic that included sensors 

depth, salinity, temperature, pH, and dissolved oxygen. The oceanographic array was deployed 

January 2013 at a depth of 17 m (MLLW) in Tracy Arm and then retrieved March 2014 (Figure 33). 

Total deployment time was 427 days. 

Significant Results to Date: Unfortunately a series of firmware malfunctions during the 

deployment resulted in the collection of only some of the desired data. Some components in the 

purchased array were “prototypes”, among the first deployed anywhere. The “bugs” were sorted 

out, faulty components replaced, all sensors serviced and rebatteried. One of the problems with 

the Tracy Arm deployment site was that it is very remote and routine maintenance is problematic. 

Accordingly, we have decided to deploy the array at the NOAA Little Port Walter marine station 

at a depth of 28 m (MLLW). This is the site of a previous coral study (Stone et al. in review). The 

data will be live fed to a land-based station, relayed to a GOES (geostationary operational 

environmental satellite) and made available via NOAA’s Satellite and Information Service 

(NESDIS) and the Alaska Ocean Observing System (AOOS). The system is currently being fieldtested and is scheduled for site deployment during the fall 2016 or spring 2017. 

Funding: DSCRTP (Alaska Initiative) funds were used to purchase the oceanographic array 

($28,000) and field supplies for the 2013 cruise ($3000). The costs of the field work (e. g. charter 

vessels, personnel support) were provided by the AFSC ($30,000). System upgrades and travel for 

training in 2016 were supported with AFSC funds ($8,000).

Point of Contact:

Robert Stone (bob.stone@noaa.gov), NOAA Fisheries, Auke Bay Laboratories 
49

Figure 33. Scuba divers deploy an oceanographic array in a red tree coral (Primnoa pacifica) thicket in Tracy 

Arm, Holkham Bay, Southeast Alaska.
50

3.11. Taxonomy of Alaska sponges and corals

Background and Objectives: We have made considerable progress with the taxonomy of both 

sponges and corals in Alaska during the past decade but some corals and quite a few sponges have 

not been collected or properly identified. Taxonomic studies are critical for accurate measures of 

biodiversity that are often used to gauge the importance of habitats. Proper taxonomic 

identifications are also important for constructing identification guides to be used in fisheries and 

surveys to record the location of coral and sponge bycatch. These data can be used by resource 

managers to identify the locations of high biodiversity and abundance that might indicate the 

location of vulnerable marine ecosystems. The objective of this study is to properly identify all 

specimens collected and appropriately preserved for all projects during the 3-year Alaska 

Initiative and to continue to support taxonomic cataloging of coral and sponge specimens 

collected during the annual AFSC RACE trawl surveys. 

Approach: This project supported dedicated collections made as part of the Red Tree Coral 

Project (Section 3.1), opportunistic collections as part of the Mapping and Modeling Project 

(Section 3.2), dedicated collections as part of the FMP Project (Section 3.3), and in support of a 

special project requested by the NPFMC to study the taxonomy and species diversity of corals and 

sponges in the Bering Sea. 

Dedicated collections of sponges and corals were made with an ROV during Project 1 in 2013 and 

2015 in the eastern Gulf of Alaska. An opportunistic collection of several sponges was made during 

the Aleutian Island towed camera survey in 2012—a large cobble became entangled in the towed 

array. Several specimens collected from the central Gulf of Alaska as part of Project 5 in 2014 were 

collected to describe seafloor habitat. Sponge and coral specimens were also collected as part of 

the annual RACE groundfish stock assessment trawl surveys to support ongoing taxonomy 

projects. The first project was a general project to inventory the sponge and coral fauna in the 

Alaskan Region and consisted of collections in the Aleutian Islands in 2012 and the Gulf of Alaska 

and Bering Sea shelf in 2013. Special collections continued in 2014 and 2015 on the Bering Sea shelf 

and on the Bering Sea slope in 2016 as part of the NPFMC-requested project.

Significant Results to Date: Corals collected as part of Project 1 in 2013 and 2015 included the 

octocorals P. pacifica, P. pacifica willeyi, Paragorgia sp., Isidella tentaculum, Calcigorgia 

spiculifera, and Halipteris sp. A. Samples of the Paragorgia specimens contributed to an ongoing 

study to examine the taxonomy of Alaskan Paragorgia using DNA PCR-sequencing (Santiago 

Herrera, Centre for Environmental Epigenetics and Development, University of Toronto and 

Robert Stone). Antipatharians collected included Chrysopathes sp. and Bathypathes cf. patula. 

Several Bathypathes specimens contributed to an ongoing study to examine the taxonomy of that 

genus (Mercer Brugler, NYC College of Technology and Robert Stone). Hydrocoral collections 

included Stylaster verrillii, S. brochi, and S. parageus columbienis. The latter collection 

represented a northern range extension for the subspecies. A single scleractinian (Caryophyllia 

arnoldi) was collected. 

Only two corals were collected as part of Project 5, the gorgonian Fanellia fraseri and the 

hydrocoral Stylaster brochi, both previously documented from the study region.

More than 100 sponge specimens were microscopically examined from the 3-year Alaska Initiative 

(2012–2014) collections and included the description of 23 new species and multiple range 
51

extensions from all three geographic regions. Twenty species of demosponges were described 

from the Aleutian Island RACE trawl survey collections: Ancorina buldira, Geodia starki, Stelleta 

anthastra, S. makushina, Dysidea kenkriegeri, Cornulum globosum, Artemisina clavulata, A. 

flabellata, Coelosphaera kigushimkada, Stelodoryx mucosa, S. siphofuscus, Raspailia 

septentrionalis, Callyspongia mucosa, Megaciella lobata, M. pituitosa, M. triangulata, Cladocroce 

attu, C. infundibulum, C. kiska, and C. toxifera. Two species of demosponges were described from 

Project 1 collections in 2015 (Hamacantha cassanoi (Figure 34) and Prosuberites salgadoi) and one 

species was described from the Gulf of Alaska RACE trawl survey collections (Latrunculia 

lincfreesei). The RACE trawl survey collections also provided specimens of Latrunculia hamanni, 

L. oparinae, and L. velera and contributed to a major revision of the family Latrunculiidae, as did 

specimens of L. austini collected as part of Project 1 in 2013 and 2015. 

Funding: Collection of specimens for taxonomic studies was supported with DSCRTP (Alaska 3-

year Initiative) funds as part of Project 1 in 2013 and 2015, Project 2 in 2012, and Project 5 in 2015. 

Special collections for the Bering Sea biodiversity study were supported by the AFSC in 2012–2016. 

Contracts for sponge taxonomy were issued each year during the 3-year Alaska Initiative (2012–

2014) using AFSC funds ($60,250) and DSCRTP funds ($26,150). Follow-up contracts for sponge 

taxonomy were issued for the Bering Sea biodiversity study using AFSC funds in 2015 ($13,222) and 

DSCRTP funds (non-Alaska Initiative) in 2016 ($19,570).

Points of Contact: 

Robert Stone (bob.stone@noaa.gov), NOAA Fisheries, Auke Bay Laboratories

Helmut Lehnert (lehnert@spongetaxonomics.de), GeoBio-Center, Ludwig-Maximilians 

University, München, Germany
52

Figure 34. Hamancantha (Vomerula) cassanoi discovered at a depth of 174 at Site 4 (Fairweather Ground) 

during the 2015 eastern Gulf of Alaska expedition.

3.12. Marine natural products studies of Alaskan sponge fauna

Background and Objectives: Corals and particularly some sponges have evolved the ability to 

produce or accumulate from associated microorganisms a diversity of unique chemical 

compounds or secondary metabolites that they utilize in predator defense, competition for 

resources, and as physiological adaptations to living in extreme environments. Many of the 

compounds are currently in early clinical or late preclinical development for use as treatments for 

cancer, tuberculosis, HIV, asthma, and many other diseases and ailments. Deep-water sponges 

show particular promise in this emerging research area, and several species collected from the 

Aleutian Islands as part of a pilot program in 2004 exhibited near 100% inhibition during primary 

screening for M. tuberculosis. Only a handful of sponge species from the Aleutian Islands have 

been examined for the presence of secondary metabolites, but so far “hit rates” for biomedically 

active compounds are on the order of 10% rather than 1% which is typical for samples collected 

elsewhere.

Opportunistic collections from past expeditions in Alaska have provided samples for important 

studies of marine natural products associated with deep-sea sponges (Na et al. 2010, Kelly et al. 

2016). Corals and particularly some sponges have evolved the ability to produce or accumulate 

from associated microorganisms a diversity of unique chemical compounds or secondary 
53

metabolites that they utilize in predator defense, competition for resources, and as physiological 

adaptations to living in extreme environments. 

Approach: As part of Project 1 in 2013 and 2014 we collected specimens of the demosponge 

Latrunculia austini (Figure 35) with ROVs and specimens of the demosponge Suberites 

montabildus (Figure 36) from the 2014 Bering Sea shelf RACE trawl survey. Specimens were 

shipped frozen to the Department of Bio-Molecular Sciences laboratory at the University of 

Mississippi for processing and examination for the presence of biomedically active compounds. 

Significant Results to Date: Preliminary work with Latrunculia austini collected from the

eastern Gulf of Alaska in 2005 (Stone et al. 2014) isolated a new pyrroloiminoquinone alkaloid 

called atkamine. Atkamine has potent bioactivity towards various types of tumor cell lines and 

with the potential target of mammalian topo-isomerase II (Zou and Hamann 2013). Collections 

made as part of Project 1 provided sufficient material for phase II of that work—a total synthesis 

to further investigate the chemistry and effectively characterize the biological potential of this 

species.

Laboratory work is scheduled to begin on the Suberites montabildus project in summer 2016. This 

species was selected for study since it was abundant enough to provide sufficient material for 

examination and had characteristics typical of sponges housing biomedically active compounds 

(e.g., dark color and odiferous). 

Funding: Collection of samples was supported with DSCRTP (Alaska 3-year Initiative) funds as 

part of Project 1 in 2013 and 2015 and as an in-kind contribution by NOAA’s AFSC as part of the 

annual RACE trawl surveys. Salary and benefits costs of the principal investigator (M. Hamann) 

and laboratory support were an in-kind contribution by the Department of Bio-Molecular 

Sciences, The University of Mississippi.

Points of Contact: 

Mark Hamann (mthamann@olemiss.edu), Department of Bio-Molecular Sciences, The University 

of Mississippi 

Robert Stone (bob.stone@noaa.gov), NOAA Fisheries, Auke Bay Laboratories
54

Figure 35. The demosponge Latrunculia austini at a depth of 94 meters at Site 3 (Shutter Ridge).

Figure 36. The demosponge Suberites montalbidus, also known as the “stinky sponge”, is very abundant in 

some areas of the southern Bering Sea. Pictured here is the catch of the stinky sponge from a bottom trawl 

survey haul in the eastern Bering Sea. 
55

4. Conclusions

The suite of projects that examined P. pacifica and associated species in the eastern Gulf of Alaska 

provided significant new information about these communities. The multibeam mapping projects 

extended coverage in the region by an additional ~167 square nautical miles to depths of 1300 m in 

areas of known or suspected P. pacifica habitat. The study confirmed that P. pacifica habitat 

extends significantly beyond the areas currently closed as HAPCs. The research also documented 

other species of coral (especially black corals) on the surrounding continental shelf. Evidence of 

damage to P. pacifica potentially from longline fishing activity was documented beyond the 

boundaries of existing HAPCs. Colony sizes were related to depth, with the largest colonies 

exceeding 2 m in height and found at the deeper depths. These large colonies (> 2 m) also formed 

a significant portion of the population, comprising 10% of the total colonies. Overall, almost 70% 

of the colonies were > 1 m in height and the recovery time for the largest colonies was estimated 

at > 100 years and 50-60 years for the average size colonies. The samples collected during this 

study using a remotely operated vehicle (ROV) were used to examine reproductive ecology, 

trophic ecology, and genetic connectivity. We confirmed that deep-water P. pacifica are 

gonochoristic and have multiple developing cohorts of oocytes that were previously observed in 

shallow-water populations. However, the study also found evidence for reduced fecundity in the 

deeper water populations. Recruitment plates deployed in P. pacifica thickets found no P. pacifica

recruits after 22 months confirming the episodic and rare nature of successful recruitment for this 

species. However, the observed recruitment of another octocoral (Calcigorgia spiculifera)

indicated the potential for the success of the technique. The settlement plates were redeployed 

for future retrieval. The trophic ecology study indicated that P. pacifica is likely feeding on both 

POM and zooplankton confirming the findings found elsewhere for deep-water octocorals. 

An important accomplishment of the Alaska Initiative was the production of maps of predicted 

occurrence of corals and sponges on a 1-ha scale for three of the four large marine ecosystems of

Alaska. The accuracy of these maps and models were confirmed (with the exception of the wider 

Gulf of Alaska) with field studies and indicated that coral and sponge ecosystems occur at 

predictable locations where hard bottom substrate is present. During the course of the project 

three previously unexplored locations were also examined using field observations, Bowers Bank 

and Ridge and the eastern and western Aleutian Islands. These explorations found that dense 

coral and sponge communities can be found throughout the western Aleutians, on the shallowest 

depths of Bowers Bank, and in the area from Sequam Pass to Unimak Island. Areas without coral 

and sponge communities were also identified, especially on the shelf south of Unalaska Island, the 

deeper areas of Bowers Ridge, and between Aggatu and Attu Islands. One of the important 

variables to come out of this modeling was the effect of current speed (either tidal currents or 

mean oceanographic currents) on the distribution of corals and sponges. The highest densities 

tended to be in areas where currents could be moderate to high (> 50 cm/s). Depth was also an 

important factor across regions controlling benthic invertebrate distribution. An important 

component of the data from this fieldwork was height and density information for corals and 

sponges in the Aleutian Islands. These new data and models will be used in the future to inform 

management decisions on where fishing closures can be most effective in protecting the oldest, 

most diverse, and densest coral and sponge communities. 

One of the foundations of the distribution maps for deep-sea corals and sponges is maps based on 

sediment and bathymetry that were developed during the Alaska Initiative. New bathymetry and 
56

sediment maps for the Aleutian Islands and parts of the Gulf of Alaska were completed during 

this project. Scientists mined the NOS (National Ocean Service) charting data as far back as the 

late 1900s and new multibeam bathymetry data from study sites all over Alaska into a single 

product that was used to derive distribution models for deep-sea corals and sponges. Future work 

will expand geological interpretation of these maps and data to provide substrate-based 

classifications for regions where enough supporting data exists.

During the Alaska Initiative, we also tried to document the differences in fisheries productivity 

using a number of measures in different types of habitats (hard substrate with coral, hard 

substrate with no coral, and bare sand habitat). Density of rockfish, especially juveniles and 

smaller species, was higher in coral habitat than the other types of habitat, which has previously 

been shown in other areas of Alaska and the U.S. West Coast. Other measures of productivity, 

such as gonosomatic index, relative fecundity, energetic content, and reproductive failure were 

also measured in the different types of habitats and highest productivity using these measures 

tended to be in the coral habitat. The preliminary results indicate that for rockfish, there may be 

benefits to coral habitat in terms of productivity that exceed the benefits of the same type of 

substrate without coral. Further data and results are forthcoming from this project as samples 

continue to be analyzed. 

Because climate change and ocean acidification are expected to have large impacts on high 

latitude ecosystems, such as those found in Alaska, monitoring programs were set up that used 

existing facilities within the AFSC to collect data. An oceanographic monitoring station will be 

established at NOAA’s Little Port Walter field station in Southeast Alaska that will interface with

other oceanographic monitoring programs (NESDIS and AOOS). The AFSC bottom trawl surveys 

also have been collecting oceanographic data using equipment purchased through the Alaska

Initiative. So far, these data have shown distinct breaks and patterns in O2 concentrations 

particularly in the Gulf of Alaska. Prior to these collections, no synoptic data sets for summer 

oceanographic conditions throughout Alaska ecosystems were being collected, with the exception 

of temperature data. Both these data sets will continue to be monitored and provided to scientists 

and managers to support ecosystem management not only for deep-sea corals and sponges, but 

for other purposes as well. 

Specimens collected during the fieldwork for the Alaska Initiative resulted in the description of 23 

new species of demosponges. Collected specimens were also critical to a major revision of an

important family of demosponges as well as providing geographical and depth range extensions 

for additional taxa. Biochemical analyses and products also have resulted in important and 

potentially medically useful alkaloids. As samples continue to be analyzed, further species and 

taxonomic revisions are likely. These findings highlight the fact that there is still much to be 

learned about the taxonomy of deep-sea corals and sponges in Alaska but significant progress has 

been made through the support of the Alaska Initiative. 

In all, the 3-year AK Coral and Sponge Initiative has provided important new information that 

addressed both immediate management needs for coral and sponge ecosystems (such as the 

distribution mapping and modeling that has already been used by the NPFMC to inform fisheries 

management), as well as longer term goals (such as setting up long term monitoring stations in 

Little Port Walter and on bottom trawl surveys that will measure the effects of climate change on 

the ecosystem). Almost as important, the initiative has resulted in further questions and 

techniques that can be used to inform future research in Alaska. 
57

5. Suggestions for future implementation/administration

Future research initiatives in Alaska would benefit from expanded consideration for logistical and 

financial challenges of working in an extremely remote location such as Alaska. The success of the 

2012-2014 Alaska Deep-Sea Coral and Sponge Initiative would have been enhanced by greater 

availability of research vessels with appropriate capabilities and additional administrative and 

data analysis support. 

Alaska has not received the NOAA vessel support that has been available for deep-sea coral 

projects in other NOAA regions. This lack of ship availability resulted in high costs for contract 

vessels (see Appendices for cost breakdown), particularly in terms of transit and fuel costs that 

heavily taxed the Initiative budget. We improvised by using commercial fishing vessels under 

contract for bottom trawl survey activities, but these contracted vessels were often not available 

during the short summer research season (when many vessels were busy fishing) or were not set 

up ideally for ROV work. The short field season and remote and difficult field conditions made it 

difficult to contract more capable vessels; several contracts solicited for vessel time received only 

single contract offer. For example, the 2014 Aleutian Islands camera survey was conducted in April 

(outside the optimal weather window), which resulted in about one-half of the total contract days 

being lost to bad weather. Similarly, we were unable to contract a vessel with a dynamic 

positioning system for the 2013 ROV cruise in the eastern Gulf of Alaska, which resulted in the 

loss of approximately 40% of available sea time. This problem will continue in the future without 

access to additional NOAA vessel time or an increased budget to offset these costs unique to the 

Alaska Region.

Administrative duties, such as contracting vessels and other research assets, took up a substantial 

amount of researchers’ time. The amount of funding allocated to hire technicians to assist with 

data processing and logistical support was also inadequate, which further taxed the time of the 

few researchers dedicated to this Initiative. For future initiatives, hiring an assistant to help 

implement administrative tasks and ensuring additional technical support for logistics and data 

processing, even at the expense of conducting new research, would likely be beneficial.

Without the support of the AFSC and other organizations, many of the projects conducted during 

the Alaska Initiative would not have been completed. For some projects, financial and technical 

support was gathered from other places (Figure 37), including AFSC and NPRB providing financial 

support for additional fieldwork (such as the 2015 ROV survey and the May 2014 fish productivity 

survey). Substantial technical support for development of stereo camera technology and analysis 

software was also provided by programs within the AFSC (the MACE Program). These types of 

contributions were very useful in making the overall project a success, but we note that these 

contributions are not always available. 
58

Figure 37. Proportion of expenditures by funding source ($3.17 million for FY12-15 combined) during the lifetime 

of the Alaska Coral and Sponge Initiative.

6. Priorities for future research

• Towed stereo camera survey based on stratified random sampling design in the Gulf of

Alaska to validate coral and sponge distribution models based on bottom trawl survey 

data.

• Assessment of the effectiveness of current fishing closures and potential pathways 

forward with spatial management of coral and sponge ecosystems using a combination 

of spatial analysis tools (such as Zonation) and fieldwork that revisits previous sites to 

assess recovery from fishing impacts.

• Population assessment for major coral species in each region that integrates existing 

life history information and distribution information to estimate sustainable mortality 

rates (bycatch rates).

• Longline and pot gear impact rates for coral and sponge communities. Despite our 

pilot efforts in this area, impact rates for these gears are still unknown.

• Research into the benthos of Arctic regions of Alaska that are largely unsurveyed, as

research on the east coast of Canada indicates that coral and sponge communities 

exist in the Arctic and could be widespread. Basic research to map the distribution and 

abundance of corals and sponges in Alaska’s Arctic is recommended.
59

• Construction/revision of potential marine benthic habitat maps to represent the 

substrate types found with corals and sponges. This would entail sampling at coral and 

sponges collection sites, and modifying our habitat characterization to include in situ 

observations. There could also be a follow-up sampling program based on predictive 

models developed from this assessment.

7. References

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growth and radiometric age validation of a deep-sea, habitat-forming gorgonian (Primnoa 

resedaeformis) from the Gulf of Alaska. Hydrobiologia 471:101-110 

Aranha R, Edinger E, Layne G, Piercey G (2014) Growth rate variation and potential 

paleoceanographic proxies in P. pacifica Insights from high- resolution trace element 

microanalysis. Deep Sea Research Part II: Topical Studies in Oceanography, 99:213- 226

Cartes JE Sorbe JC (1999) Estimating secondary production in bathyal suprabenthic peracarid 

crustaceans from the Catalan Sea slope (western Mediterranean; 391-1255 m). Journal of 

Experimental Marine Biology and Ecology 239: 195–210

Davenport SR, Bax NJ (2002) A trophic study of a marine ecosystem off southeastern Australia 

using stable isotopes of carbon and nitrogen. Canadian Journal of Fisheries and Aquatic 

Sciences 59: 514–530

Greene HG, O’Connell VM, Brylinsky CK (2011) Tectonic and glacial related seafloor 

geomorphology as possible demersal shelf rockfish habitat surrogates – examples along 

the Alaskan convergent transform boundary. Continental Shelf Research v. 31, p. 539-553. 

Golden NE, Reid JA, Zimmermann M, Lowe EN, Hansen AS (2016) Digitized seafloor 

characterization data from the Gulf of Alaska: U.S. Geological Survey: Santa Cruz, CA, 

http://dx.doi.org/10.5066/F7CV4FT9

Harvey CJ, Hanson PC, Essington TE, Brown PB, Kitchell JF (2002) Using bioenergetics models to 

predict stable isotope ratios in fishes. Canadian Journal of Fisheries and Aquatic Sciences 

59: 115–124

Heifetz J, Wing BL, Stone RP, Malecha PW, Courtney DL (2005) Corals of the Aleutian Islands. 

Fisheries Oceanography 14 (suppl) pp. 131-138

Heifetz J (2002) Coral in Alaska: distribution, abundance, and species associations. Hydrobiologia 

471: 19−28

Kelly M, Sim-Smith C, Stone R, Samaai R, Reiswig H, Austin W (2016) New arrangements within 

Latrunculia (Demospongiae, Poecilosclerida, Latrunculiidae) for North and South Pacific 

species. Zootaxa 4121 (1): 1–48

Krieger KJ (2001) Coral (Primnoa) impacted by fishing gear in the Gulf of Alaska. Pages 106–116 in 

Martin-Willison JH, et al., (eds). Proceedings of the First International Symposium on 

Deep-Sea Corals, Ecology Action Centre and Nova Scotia Museum, Halifax, Nova Scotia.

Krieger KJ, Wing BL (2002) Megafauna associations with deepwater corals (Primnoa spp.) in the 

Gulf of Alaska. Hydrobiologia 471: 83–90

Lacharité M, Metaxas A (2013) Early life history of deep-water gorgonian corals may limit their 

abundance. PLoSONE 8:e65394. doi: 10.1371/journal.pone.0065394
60

Malecha PW, Stone RP, Heifetz J (2005) Living substrate in Alaska: distribution, abundance and 

species associations. Am Fish Soc Symp 41: 289−299

Masuda MM, Stone RP (2015) Bayesian logistic mixed-effects modelling of transect data: relating 

red tree coral presence to habitat characteristics. ICES Journal of Marine Science. DOI: 

10.1093/icesjms/fsv163

McCutchan JH Jr, Lewis WM Jr, Kendall C, McGrath CC (2003) Variation in trophic shift for stable 

isotope ratios of carbon, nitrogen, and sulfur. Oikos 102: 378–390

Minagawa M, WadaE (1984) Stepwise enrichment of 15N along food chains: further evidence and 

the relation between δ15N and animal age. Geochimica et Cosmochimica Acta 48: 1135–1140

Morrison CL, Springmann MJ, Shroades KM, Stone RP (2015) Development of twelve 

microsatellite loci in the red tree corals Primnoa resedaeformis and P. pacifica. 

Conservation Genetics Resources 7: 763–765

Na M, Ding Y, Wang B, Tekwani BL, Schinazi RF, Franzblau S, Kelly M, Stone R, Li X-C, Ferreira

D, Hamann MT (2010) Anti-infective discorhabdins from deepwater Alaskan sponges of 

the genus Latruculia. Journal of Natural Products 73(3):383–387

Peterson BJ, Fry B (1987) Stable isotopes in ecosystem studies. Annual Review of Ecology and 

Systematics 18: 293–320

Post DM (2002) Using stable isotopes to estimate trophic position: models, methods, and 

assumptions. Ecology 83: 703–718

Rooper CN, Boldt JL (2005) Distribution of juvenile Pacific ocean perch (Sebastes alutus) in the 

Aleutian Islands in relation to benthic habitat. Alaska Fish Res Bull 11:102-112

Rooper CN, Boldt JL, Zimmermann M (2007) An assessment of juvenile Pacific Ocean Perch 

(Sebastes alutus) habitat use in a deepwater nursery. Est. Coast. Shelf Sci. 75:371-380

Rooper CN, Sigler M, Goddard P, Malecha PW, Towler R, Williams K, Wilborn R, Zimmermann M 

(2016) Validation and improvement of species distribution models for structure forming 

invertebrates in the eastern Bering Sea with an independent survey. Mar. Ecol. Prog. Ser. 

551:117-130

Rooper CN, Zimmermann M, Prescott M, Hermann A (2014) Predictive models of coral and 

sponge distribution, abundance and diversity in bottom trawl surveys of the Aleutian 

Islands, Alaska. Mar. Ecol. Prog. Ser. 503:157-176

Rooper, CN, Zimmermann M, Prescott MM (in press) Comparison of modeling methods to 

predict the spatial distribution of deep-sea coral and sponge in the Gulf of Alaska. 

Submitted to Deep Sea Research II

Sigler MS, Rooper CN, Hoff GR, Stone RP, McConnaughey RA, Wilderbeur TK (2015) Faunal 

features of submarine canyons on the eastern Bering Sea slope. Mar. Ecol. Prog. Ser. 

526:21-40

Stone RP, Shotwell K (2007) State of the deep coral ecosystems of the Alaska Region: Gulf of 

Alaska, Bering Sea, and the Aleutian Islands. In The State of Deep Coral Ecosystems of the 

United States (Lumsden SE, Hourigan TF, Bruckner AW, Dorr G, eds.), p. 65–108. U.S. 

Dep. Commer., NOAA Tech. Memo. CRCP-3. Silver Spring, MD. 

Stone RP, Masuda MM, Karinen JF (2014) Assessing the ecological importance of red tree coral 

thickets in the eastern Gulf of Alaska. ICES Journal of Marine Science: DOI: 

10.1093/icesjms/fsu190

Stone RP (2014) The ecology of deep-sea coral and sponge habitats of the central Aleutian Islands 

of Alaska. NOAA Prof Paper NMFS 16. US Department of Commerce, Seattle, WA

Stone RP, Malecha PW, Masuda MM (2017) A five-year, in situ growth on shallow-water 

populations of the gorgonian octocoral (Calcigorgia spiculifera) in the Gulf of Alaska.

PLoSOne. DOI:10.1371/journal.pone.0169470
61

Waller RG, Stone R, Johnstone J, Mondragon J (2014) Sexual Reproduction and Seasonality of the 

Alaskan Red Tree Coral, P. pacifica. PLoS One. DOI:10.1371/journal.pone.0090893 

Wilborn R, Rooper CN, Goddard P, Williams K, Towler R (in review) Distribution, abundance, 

diversity and size of cold-water corals and sponges in the Aleutian Islands, Alaska. DeepSea Research II

Williams K, Rooper CN, Towler R (2010) Use of stereo camera systems for assessment of rockfish 

abundance in untrawlable areas and for recording Pollock behavior during midwater 

trawls. Fishery Bulletin. 108:352–362

Williams K, Towler R, Goddard P, Wilborn R, Rooper C (2016) SEBASTES stereo image analysis 

software. AFSC Processed Rep. 2016-03, 42 p. Alaska Fish. Sci. Cent., NOAA, Natl. Mar. 

Fish. Serv., 7600 Sand Point Way NE, Seattle WA 98115.

Zimmermann M, Benson JL (2013). Smooth sheets: How to work with them in a GIS to derive 

bathymetry, features and substrates. U.S. Dep. Commer., NOAA Tech. Memo. NMFSAFSC-249, 52 p.

Zimmermann M, Prescott MM (2014) Smooth sheet bathymetry of the central Gulf of Alaska. U.S. 

Dep. Commer., NOAA Tech. Memo. NMFS-AFSC-287, 54 p.

Zimmermann M, Prescott MM, Rooper CN (2013) Smooth sheet bathymetry of the Aleutian 

Islands. U.S. Dep. Commer., NOAA Tech. Memo. NMFS-AFSC-250, 43 p. 

Zou Y, Hamann MT (2013) Atkamine: a new pyrroloiminoquinone scaffold from the cold water 

Aleutian Islands Latrunculia sponge. Organic Letters 15 (7): 1516–1519

8. Appendices

8.1. Budget expenditures

In total the Alaska Coral and Sponge Initiative received $2,558,812 from FY12-FY15. In FY12, $900K 

was allocated, in FY13 $850K was allocated, in FY14, $800K was allocated and in FY15 we received 

$8,811. The major fieldwork project studying P. pacifica in the eastern Gulf of Alaska required 

about 49% of the total funds over the life of the project (Figure A1). It should be noted that this 

fieldwork supported collections and data from the Primnoa recovery and landscape ecology 

project, the Primnoa genetic connectivity, the geological substrate mapping project, the coral 

recruitment study and the taxonomic and other collections project. These projects were all 

successfully piggybacked onto the eastern Gulf of Alaska P. pacifica project. The other two major 

fieldwork projects required 22% (Aleutian Islands mapping project) and 12% (fish productivity 

study) of the total funds. 
62

Figure A1. Expenditures by project for FY12-15 in the Alaska Coral and Sponge Initiative (DSCRTP contribution 

only).

It is also important to note that support from outside sources was also obtained over the course of 

these projects. In FY12-15 a funded proposal to the North Pacific Research Board paid for 47% 

(~$272K) of the fish productivity study by funding both a portion of the fieldwork and the 

associated laboratory analyses. In FY13 the Primnoa recovery project received $52.5K from a 

successful proposal to the AFSC/AKR HEPR Program. Also in FY13, the fish productivity project 

received $31.8K in additional funds from the AFSC/AKR HEPR Program to support laboratory 

analysis of rockfish fecundity. The sponge and coral taxonomy contracts received $93K from 

outside sources, the southeast Alaska monitoring project and Primnoa genetics projects received 

$38K and $2K respectively from the AFSC. The HEPR Program also provided funding ($60.3K) to 

study the reproductive ecology of Primnoa. Finally, the southeast Alaska ROV project received 

$231.7K in FY15 to support ROV activities and sample collection. In total (not including in-kind 

contributions of personnel time, salary and benefits), the AFSC and NPRB provided ~$612K of 

additional funding for the AKCSI or about 20% of the total cost of the program. 

In terms of items were funding was spent, the largest cost for the project was for vessel charters 

for fieldwork and fuel for those charters (Figure A2). Together these two items accounted for 38% 

of the total funding. ROV contracts (20%) and the multibeam mapping conducted in southeast 

Alaska (13%) accounted for another large portion of the budget. Equipment and supplies 

accounted for 10% of the project cost. Contract personnel, grants to Universities made up 8% of 

the budget. Other contracts (4%), travel (4%), overtime for fieldwork (3%), and transportation of 

equipment (1%) made up the remainder of the budgets. 
63

These values represent only the DSCRTP contribution ($2.55 million). Since much of the external 

funds were used to offset vessel and fuel costs, the percentage of the total budget consumed by 

these two components rises to 47% when the external funds are considered.

Figure A2. Expenditures by type for FY12-15 during the lifetime of the Alaska Coral and Sponge Initiative.

8.2. Publications to date

Goddard P, Wilborn R, Rooper C, Williams K, Towler R (2017) Results of the 2012 and 2014 

underwater camera survey of the Aleutian Islands. US Dept. Commer., NOAA Tech. 

Memo. NMFS-AFSC-351, 509 p. 

Golden NE, Reid JA, Zimmermann M, Lowe EN, Hansen AS (2016) Digitized seafloor 

characterization data from the Gulf of Alaska: U.S. Geological Survey: Santa Cruz, CA, 

http://dx.doi.org/10.5066/F7CV4FT9.Kelly M, Sim-Smith C, Stone R, Samaai R, Reiswig H, 

AustinW (2016) New arrangements within Latrunculia (Demospongiae, Poecilosclerida, 

Latrunculiidae) for North and South Pacific species. Zootaxa 4121 (1): 1–48Lehnert H, Stone 

RP (2013) Four new species of Haplosclerida (Porifera, Demospongiae) from the Aleutian 

Islands, Alaska. Zootaxa 3700 (4): 573–582

Lehnert H, Stone RP (2014) Aleutian Ancorinidae (Porifera, Astrophoridae): description of three 

new species from the genera Stelletta and Ancorina. Zootaxa 3826 (2): 341–355

Lehnert H, Stone RP (2014) Two new species of sponges (Porifera, Demospongiae) from the 

Aleutian Islands, Alaska. Journal of the Marine Biological Association of the United 

Kingdom. DOI:10.1017/S0025315414001131
64

Lehnert H, Stone RP (2015) New species of sponges (Porifera, Demospongae) from the Aleutian 

Islands and Gulf of Alaska. Zootaxa. 4033 (4): 451–483

Lehnert H, Stone RP (2016) A comprehensive inventory of the Gulf of Alaska sponge fauna with 

the description of two new species and geographic range extensions. Zootaxa 4144 (3):365–

382.

Lehnert H, Stone RP (2016) Suggestion of Raspailia (Hymeraphiopsis) septentrionalis as 

replacement name for Raspailia (Hymeraphiopsis) fruticosa Lehnert & Stone, 2015. 

Zootaxa 4092 (1): 139–139.

Lehnert H, Stone RP, Drumm D (2014) Geodia starki sp. nov. (Porifera, Demospongiae, 

Astrophorida) from the Aleutian Islands, Alaska, USA. Journal of the Maine Biological 

Association of the United Kingdom 94 (2): 261–265. 

Morrison CL, Springmann MJ, Shroades KM, Stone RP (2015) Development of twelve 

microsatellite loci in the red tree corals Primnoa resedaeformis and P. pacifica. 

Conservation Genetics Resources 7: 763–765

Rooper CN, Sigler M, Goddard P, Malecha PW, Towler R, Williams K, Wilborn R, Zimmermann M 

(2016) Validation and improvement of species distribution models for structure forming 

invertebrates in the eastern Bering Sea with an independent survey. Mar. Ecol. Prog. Ser. 

551:117-130

Rooper CN, Zimmermann M, Prescott M, Hermann A (2014) Predictive models of coral and 

sponge distribution, abundance and diversity in bottom trawl surveys of the Aleutian 

Islands, Alaska. Mar. Ecol. Prog. Ser. 503:157-176

Rooper CN, Wilborn R, Goddard P, Williams K, Towler R, Hoff GR (in press) Validation of deepsea coral and sponge distribution models in the Aleutian Islands, Alaska. Submitted to 

Fisheries Research

Rooper, CN, Zimmermann M, Prescott MM (in press) Comparison of modeling methods to 

predict the spatial distribution of deep-sea coral and sponge in the Gulf of Alaska. 

Submitted to Deep Sea Research II

Saenger C, Gabitov RI, Farmer J, Watkins JM, Stone R. (2017) Linear correlations in bamboo coral 

13C and 18O sampled by SIMS and micromill: evaluating paleoceanographic potential and 

biomineralization mechanisms using 11B and Δ47 composition. Chemical Geology 454:1–14

Sigler MS, Rooper CN, Hoff GR, Stone RP, McConnaughey RA, Wilderbeur TK (2015) Faunal 

features of submarine canyons on the eastern Bering Sea slope. Mar. Ecol. Prog. Ser. 

526:21-40

Wilborn R, Conrath C, Rooper C, Knoth B (2017) Results from the underwater camera survey of 

the 49 fathom pinnacle and snakehead bank sites near Kodiak Island, Alaska. AFSC 

Processed Rep. 2017-06, 75 p.

Wilborn R, Rooper CN, Goddard P, Williams K, Towler R (in review) Distribution, abundance, 

diversity and size of cold-water corals and sponges in the Aleutian Islands, Alaska. DeepSea Research II

Williams K, Towler R, Goddard P, Wilborn R, Rooper C (2016) SEBASTES stereo image analysis 

software. AFSC Processed Rep. 2016-03, 42 p. Alaska Fish. Sci. Cent., NOAA, Natl. Mar. 

Fish. Serv., 7600 Sand Point Way NE, Seattle WA 98115.

Zimmermann M, Prescott MM (2014) Smooth sheet bathymetry of the central Gulf of Alaska. U.S. 

Dep. Commer., NOAA Tech. Memo. NMFS-AFSC-287, 54 p.

Zimmermann M, Prescott MM, Rooper CN (2013) Smooth sheet bathymetry of the Aleutian 

Islands. U.S. Dep. Commer., NOAA Tech. Memo. NMFS-AFSC-250, 43 p.
65

8.3. Electronic resources:

Site Characterization Reports

• Aleutian Islands - https://www.afsc.noaa.gov/Publications/AFSC-TM/NOAA-TMAFSC-351.pdf

• FMP species productivity sites -

https://www.afsc.noaa.gov/Publications/ProcRpt/PR2017-06.pdf

Image gallery 

• https://deepseacoraldata.noaa.gov/gallery

Sediment and bathymetry maps for EBS, GOA and AI

• http://www.afsc.noaa.gov/RACE/groundfish/Bathymetry/default.htm

2011 - Research Priorities Workshop Report

• http://docs.lib.noaa.gov/noaa_documents/CoRIS/Alaska_DeepSea_Coral_Workshop_Report_Final.pdf