December 2015

Special Issue: A New Look at the Low-Latitude Western Pacific

Oceanography

THE OFFICIAL MAGAZINE OF THE OCEANOGRAPHY SOCIETY

VOL.28, NO.4, DECEMBER 2015

A NEW LOOK AT THE

LOW-LATITUDE WESTERN PACIFIC

sea-birdscientific.com

Sea Oil-in-Water Locator

Introducing the

SeaOWL UV-A

TM

Oceanography | December 2015

74

54

SPECIAL ISSUE: A NEW LOOK AT THE

LOW-LATITUDE WESTERN PACIFIC

16

FROM THE GUEST EDITORS. A New Look at Circulation in the Western

North Pacific: Introduction to the Special Issue

By D.L. Rudnick, S. Jan, and C.M. Lee

24

The Pacific North Equatorial Current: New Insights from the Origins of

the Kuroshio and Mindanao Currents (OKMC) Project

By B. Qiu, D.L. Rudnick, I. Cerovecki, B.D. Cornuelle, S. Chen,

M.C. Schönau, J.L. McClean, and G. Gopalakrishnan

34

The Mindanao Current: Mean Structure and Connectivity

By M.C. Schönau, D.L. Rudnick, I. Cerovecki, G. Gopalakrishnan,

B.D. Cornuelle, J.L. McClean, and B. Qiu

46

Shifts in Chlorophyll a off Eastern Luzon, Philippines, Associated with

the North Equatorial Current Bifurcation Latitude

By O.C. Cabrera, C.L. Villanoy, I.D. Alabia, and A.L. Gordon

54

The Kuroshio and Luzon Undercurrent East of Luzon Island

By R.-C. Lien, B. Ma, C.M. Lee, T.B. Sanford, V. Mensah, L.R. Centurioni,

B.D. Cornuelle, G. Gopalakrishnan, A.L. Gordon, M.-H. Chang, S.R. Jayne,

and Y.J. Yang

64

Two Mechanisms Cause Dual Velocity Maxima in the Kuroshio

East of Taiwan

By K.-C. Yang, J. Wang, C.M. Lee, B. Ma, R.-C. Lien, S. Jan, Y.J. Yang,

and M.-H. Chang

74

Mean Structure and Fluctuations of the Kuroshio East of Taiwan from

In Situ and Remote Observations

By Y.J. Yang, S. Jan, M.-H. Chang, J. Wang, V. Mensah, T.-H. Kuo,

C.-J. Tsai, C.-Y. Lee, M. Andres, L.R. Centurioni, Y.-H. Tseng, W.-D. Liang,

and J.-W. Lai

84

Mean Structure and Variability of the Kuroshio from Northeastern Taiwan

to Southwestern Japan

By M. Andres, S. Jan, T.B. Sanford, V. Mensah, L.R. Centurioni,

and J.W. Book

contents

VO L . 2 8 , N O. 4 , D E C E M B E R 2 0 1 5

Oceanography

46

Oceanography | December 2015

ON THE COVER

Photo taken from R/V Ocean Researcher I after finishing physical

and biological sampling along a section of the Kuroshio east of

Taiwan in September 2014. The large ocean circulation such as

that of the North Pacific conveys tremendous heat, water mass,

and energy from the equatorial to the mid-latitude ocean and

thus is a vital component of Earth’s climate system. The joint

effort of the US Origins of the Kuroshio and Mindanao Current

and the Taiwan Observations of the Kuroshio Transports and

Variability programs is providing a new look into the variabil-

ity and connectivity of the North Equatorial Current, Mindanao

Current, and Kuroshio in the western Pacific.

CONTACT US

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SPECIAL ISSUE SPONSOR

Production of this issue of Oceanography was

supported by the Office of Naval Research

through a grant to Scripps Institution of

Oceanography.

SPECIAL ISSUE GUEST EDITORS

• Daniel Rudnick, Scripps Institution of

Oceanography

• Sen Jan, National Taiwan University

• Craig Lee, University of Washington

DEPARTMENTS

04

QUARTERDECK. The Career Profiles Column: Providing Job-Hunting

Options and Insights for Five Years and Counting

By E.S. Kappel

07

FROM THE PRESIDENT. A Tribute to John A. Knauss (1925–2015)

By M.S. Lozier

08

COMMENTARY. Bathymetric Extent of Recent Trawl Damage to the Seabed

Captured by an ROV Transect in the Alboran Sea

By M.L. Brennan, M. Canals, D.F. Coleman, J.A. Austin Jr., and D. Amblas

12

RIPPLE MARKS. Life in a Tangled Mangal: Turning the Tide for Mangroves

By C.L. Dybas

96

HANDS-ON OCEANOGRAPHY. Mimicking the Rayleigh Isotope Effect

in the Ocean

By E.M. Griffith, J.D. Ortiz, and A.J. Jefferson

102 CAREER PROFILES. Jordan Dawe, Data Engineer, EnerNOC •

Michele Morris, Consultant

Oceanography Special Issues

March 2016

Graduate Education in the Ocean Sciences

June 2016

Bay of Bengal: From Monsoons to Mixing

September 2016

GoMRI Gulf Oil Spill & Ecosystem Science

December 2016

Ocean-Ice Interaction

March 2017

Sedimentary Processes Building a Tropical Delta Yesterday,

Today, and Tomorrow: The Mekong System

June 2017

International Cooperation in Harmful Algal Bloom Science

American Meteorological Society

96th Annual Meeting

January 10–14, 2016, New Orleans, LA, USA

http://annual.ametsoc.org/2016

2016 Ocean Sciences Meeting

February 21–26, 2016, New Orleans, LA, USA

http://meetings.agu.org/meetings/os16

Ocean Optics XXIII

October 23–28, 2016, Victoria, BC, Canada

http://www.oceanopticsconference.org

Oceanography | Vol.28, No.4

Upcoming

Upcoming Events

Oceanography | December 2015

Editor

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Oceanography

http://tos.org/oceanography

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Program

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Sciences

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to disseminate knowledge of oceanography and

its application through research and education, to

promote communication among oceanographers,

and to provide a constituency for consensus-

building across all the disciplines of the field.

OFFICERS

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Oceanography | December 2015

Oceanography Special Issues

Oceanography | Vol.28, No.4

Oceanography published its first “Career

Profiles” column in the June 2010 issue,

with the aim of providing graduate stu-

dents with a window into the array of job

possibilities outside of academia. Over

the past five years, “Career Profiles” has

become one of the most popular pages

on The Oceanography Society website

(http://tos.org/career-profiles). To date,

we’ve published 47 profiles (counting the

two in this issue on pages 102 and 103).

To produce these career profiles, we

ask people to answer a series of questions:

1. Degree: When, where, what, and

what in?

2. Did you stay in academia at all, and if

so, for how long?

3. How did you go about searching for a

job outside of the university setting?

4. Is this the only job (post-academia)

that you’ve had? If not, what else did

you do?

5. What is your current job? What path

did you take to get there?

6. What did your oceanographic educa-

tion (or academic career) give you that

is useful in your current job?

7. Is the job satisfying? What aspects of

the job do you like best/least?

8. Do you have any recommendations for

new grads looking for jobs?

As part of the “Career Profiles” fifth anni-

versary celebration, this column assem-

bles some of the most useful and inter-

esting recommendations for job seekers.

By far the most common piece of advice

concerns the importance of networking.

THE

CAREER PROFILES COLUMN

Providing Job-Hunting Options and Insights for Five Years and Counting

QUARTERDECK

In addition, many of the people we’ve

profiled stressed that the skills gained in

earning a PhD in the ocean sciences qual-

ifies students for an unexpectedly large

variety of rewarding positions outside

of academia—but that students need to

be open to learning about and applying

for those positions.

GENERAL RECOMMENDATIONS

It is important to keep your eyes and mind

open to positions you might not have con-

sidered, while keeping sight of the kind of

work you enjoy and the kind of lifestyle you

would like to lead.

— Kara Lavender Law

Think about what your best skills and special

talents are. If you focus on those areas, you

are most likely to find (or create) opportu-

nities for personal excellence. — Ellen Lettvin

Know that transitioning from your spe-

cialty to something different or with a

broader scope than what you have been

accustomed to in school can be disorient-

ing at times, but can also lead to rewarding

new opportunities.

— Kris Ludwig

Be open to nontraditional opportuni-

ties. Your academic training and related

activities have provided basic skills

that can be applied to a variety of non-

academic positions.

— Mitchell Malone

Have confidence in your abilities, but more

importantly, in your ability to learn on the

job. After all, that is what your training

as a scientist has prepared you for—to

work independently and figure things

out for yourself.

— Cheryl Peach

Think about what truly floats your boat, talk

to people to better understand what oppor-

tunities exist, and don’t expect to go from

point A to point B in one shot. Be flexible

and take a few chances! — Audrey Rogerson

NETWORK, NETWORK, NETWORK

The best jobs, the best opportunities, and

the best future all lie in the people you

know and what they can do for you. Ask

your friends, colleagues and mentors for

help…they will give it.

— Paul Bunje

Don’t be afraid to email someone you don’t

know who has a job that seems interesting

to you and ask them to spend a few min-

utes talking with you.

— Heather Deese

Use the alumni communities to meet folks

who have the jobs you want. Take them to

lunch, ask all the questions above, and lis-

ten closely. Stay in touch with them even

after you find a job.

— Nick Drenzek

Go to as many interviews and job fairs as

possible to see what’s available. — John A. Farre

Devote significant time and energy to

the care and feeding of your profes-

sional network—both peers and senior-

level mentors… A really critical aspect

of networking is to give as much as you

get—in other words, be on the lookout for

Oceanography | December 2015

Ellen S. Kappel, Editor

opportunities for your colleagues, and pro-

vide support when they need it. Don’t be

that guy or gal who is only in touch when

they need something.

— Maria G. Honeycutt

Feel free to set up informational interviews

with organizations that interest you—

you’ll be amazed at what you can learn

in a half hour.

— Jon Kaye

Talk with as many people from as diverse

a network as possible. After each informa-

tional interview, a good practice is to ask

the person you spoke with to recommend a

few others with whom you can speak…It is

a great way to learn about jobs and career

paths that you may not have known about,

to establish a professional network, and

even to find your potential job. — Winnie Lau

SKILLS

Practice public speaking, learn to write,

and, ideally, take an improvisational act-

ing course—or do all three. I cannot over-

emphasize the importance of being able to

persuasively make an argument or present

a compelling story around a set of data in

person or through writing. These skills are

absolutely essential to success as a researcher

or in most nontraditional career paths for

scientists that I know.

— Heather Deese

If you think you might be interested in oper-

ational oceanography, realize that we do

not do everything in Matlab. Shell script-

ing, command-line-based packages such

as GMT, languages like Perl or Python,

C or Fortran, familiarity with formats like

NetCDF, HDF, and relational databases,

services like OPeNDAP and revision con-

trol systems like CVS, RCS, or git—these

are all valuable skills and well within the

grasp of someone getting a PhD in a quan-

titative science.

— Deirdre Byrne

THE RESUME AND INTERVIEW

I’ve reviewed enough applications for vari-

ous positions to feel the need to include the

following: when applying for a position, be

absolutely certain that your application is

well written, clear, and to the point. Make

certain that there are no typos or gram-

matical errors in your CV and especially

in your cover letter. It’s astounding to me

how many one-page cover letters have glar-

ing errors that reflect a lack of care and will

nearly always disqualify any application.

Finally, if you reach the interview stage,

go in with the attitude that the job is yours

to lose, because, really, it is. Be engaging

and interested, and arrive having done

your homework on the position. Most

importantly, have a very good answer ready

as to why you’re interested in the position,

because that’s one question you’re sure to be

asked. Being interested and personable are

critical to a successful interview—always

remember that those interviewing you are

not only assessing your qualifications for

the position but are also evaluating you as

a potential colleague. In my opinion, the

key to a successful interview is not only to

show why you are the most qualified per-

son for the position but also to come across

as someone with whom the interviewers

would want to work.

— Robert L. Burger

Keep an online version of your professional

self up to date and easily accessible…If you

are seeking a nonacademic position, do

not circulate a CV. Instead, write a resume

with sections detailing your executive/

leadership, scientific, and technical qual-

ifications… When you present your work

to a potential nonacademic employer,

be careful to mention not only the scien-

tific results, but how you got there—did

you have to collaborate widely, strategize

a fallback plan when your original exper-

iments fell through, manage a budget,

organize a cruise?

— Deirdre A. Byrne

Because employers look for people who

know how to work and who demonstrate

that they can get along with others, some-

times in stressful work environments, your

references become one of the most important

parts of any job application. — Carol Janzen

Every time I submit a job application, I

refine my resume to make sure it is aligned

with the job description. The same is true

for cover letters. This step takes time, but

it’s critical in demonstrating that you are

qualified for the position.

— Kelly A. Kryc

FELLOWSHIPS

If you are looking to move outside of aca-

demia, there are a few fellowship pro-

grams similar to the AAAS Science and

Technology Fellowship I  received that

can help open doors—such as the Knauss

Fellowship (also known as the Sea Grant

Fellowship), the Presidential Management

Fellowship, and ORISE (Oak Ridge Institute

for Science and Education) Fellowship with

the Environmental Protection Agency.

Even if you are not directly interested in

policy, it might be worthwhile to spend a

year or two in one of these fellowship pro-

grams because it can lead to many non-

policy opportunities, such as working for

a nonprofit organization on conservation

science, for a consulting firm, or for a gov-

ernment agency doing analysis.

— Winnie Lau

In the next issue of Oceanography, I’ll

summarize some of the most helpful

answers provided by the people we’ve pro-

filed to the question about what aspects of

their oceanographic education have been

useful in their jobs.

As a final note, remember that the

“Career Profiles” column requires a

steady stream of new and interesting

people to profile. Please send me sugges-

tions and email contact information (at

ekappel@geo-prose.com) for colleagues

who work “outside of academia” and who

might be willing to submit a profile. Self-

nominations are welcome. If the contri-

butions over the past five years are any

indication, we have not yet covered the

full range of job possibilities nor closed

the book on the wisdom of how to suc-

cessfully seek employment.

The 2015 Munk Award

is Presented to Carl Wunsch

On November 4, 2015, Dr. Carl Wunsch

(Professor Emeritus, Massachusetts Institute

of Technology, and Visiting Professor,

Harvard University) was presented with

the Walter Munk Award for distinguished

research in oceanography related to sound

and the sea. This event took place during

the Acoustical Society of America Meeting

in Jacksonville, Florida. The citation for

Dr. Wunsch that will be included on the cer-

tificate signed by the Secretary of the Navy

is as follows:

Carl Wunsch is honored as one of the fathers

of ocean acoustic tomography and as a princi-

pal contributor to our understanding of the physical processes that affect the propagation

of sound in the sea. He adapted the machinery of inverse methods and ocean state esti-

mation to enable the use of using acoustic data to estimate the ocean sound-speed (and

by inference, temperature) field and to the interpretation of a wide variety of other ocean-

ographic data. He applied inverse methods to the data obtained in pioneering tomo-

graphic experiments and made seminal contributions to the theoretical developments

that underlie the field.

After the award presentation, Dr. Wunsch delivered the Munk Award lecture. He

will also deliver a lecture during the awards session at the Ocean Sciences Meeting in

New Orleans, Louisiana, on Wednesday morning, February 24, 2016.

ABOUT THE MUNK AWARD

http://tos.org/munk-award

The Oceanography Society, the Office

of Naval Research, and the Office of the

Oceanographer of the Navy jointly grant

the Walter Munk Award. Recipients are

selected based on their:

• Significant original contributions to the

understanding of physical ocean pro-

cesses related to sound in the sea

• Significant original contributions to the

application of acoustic methods to that

understanding

• Outstanding

service

that

fosters

research in ocean science and instru-

mentation contributing to the above

The award consists of a medal designed

by Judith Munk, a commemorative lapel

pin, and a certificate bearing the signa-

tures of the Secretary of the Navy and the

President of The Oceanography Society.

The nomination deadline for the next

award is March 31, 2017. All nomi-

nations should be submitted either

in MS Word or Adobe PDF format to

info@tos.org.

Left to right: Robert Headrick, Carl Wunsch,

and Peter Worcester

TOS TOWN HALL AT OSM 2016

What’s Right and What’s Wrong with Graduate Education in the Ocean Sciences?

Please join us for a lively discussion among panelists, grad-

uate students, early career scientists, faculty members, and

deans that will focus on new directions and innovations that

could improve or even transform graduate education in the

ocean sciences. Discussion will focus on potential changes to

graduate student training that would better prepare stu-

dents for a variety of careers in this changing job market, and

on how the ocean science community might work across

institutions and universities to effect these changes. Bring

your ideas for building stronger marine science programs.

Refreshments will be served.

Wednesday, February 24, 2016

6:30–7:30 pm

Morial Convention Center Rooms 211–213

Oceanography | December 2015

I met John Knauss only once, in passing, over 20 years ago, after I

had given a seminar at the University of Rhode Island. Reflecting

on that encounter later that evening, I was chagrined that I had

squandered the opportunity to ask him how it was possible to

do so many things so well for so long. The list is exhaustive:

educator, researcher, seagoing oceanographer, program man-

ager, government and university administrator, founding dean,

and author. Most oceanographers, even with careers stretching

the length of Knauss’s, can check just a couple of those boxes.

In fact, are there oceanographers like John Knauss anymore?

Contemplating this question reminds me of how baseball has

evolved over the past few decades. Where once there were start-

ing and relief pitchers, today there are starting pitchers, mid-

dle relief and long relief pitchers, setup pitchers and closers, as

well as left-hand specialists and, seemingly, some pitchers to

simply warm the bench. Few pitch the whole game today. But

John Knauss—he pitched the whole game. He started, he was the

relief, he closed, and he pitched the extra innings. Going the dis-

tance meant that his reach was tremendous, as evidenced by the

titles of the articles in the 2001 issue of Oceanography honoring

John’s 50 years of service to ocean science.

On the research front, as a graduate student at Scripps

Institution of Oceanography, John made the first comprehensive

measurements of the Pacific Equatorial Undercurrent. As his

career progressed, he increasingly turned his attention to marine

policy and management. He played an instrumental role in the

formation of the National Sea Grant Program in 1966. He was

the only academic oceanographer on the Stratton Commission,

authorized by Congress in 1966 to make recommendations for

the “full and wise use of the marine environment.” Those rec-

ommendations included creation of the National Oceanic and

Atmospheric Administration and the formulation of the Coastal

Zone Management Act. His strong belief in freedom of research

on the high seas led to his appointment as a delegate to confer-

ence discussions that culminated in the Law of the Sea Treaty,

negotiated in the 1970s and adopted in 1982. John’s passion and

talent for marine policy and management were evident during

his tenure as Under Secretary for Oceans and Atmosphere in

the Department of Commerce and administrator of the National

Oceanic and Atmospheric Administration (1989–1993). His

contributions to marine science, policy, and management were

recognized by a National Sea Grant Award, an Ocean Sciences

Award from the American Geophysical Union, and fellowship in

the American Geophysical Union, the American Association for

the Advancement of Science, and the Marine Technology Society.

M. Susan Lozier, TOS President

A Tribute to John A. Knauss

(1925–2015)

And there’s more. John was deeply interested in graduate edu-

cation. His graduate study at Scripps impressed upon him the

importance and utility of a multidisciplinary core education, a

priority he brought to the University of Rhode Island in 1962

when he was appointed as the founding dean of the Graduate

School of Oceanography. John’s interest in graduate education

extended beyond preparing students for academic research into

the realm of what today we would call public scholarship. His

accomplishments in marine policy and management, built upon

a background as a research oceanographer, were a strong testa-

ment to the contributions that PhD oceanographers could make

outside the walls of the academy. Fittingly, the Washington, DC,

internships created as part of the Sea Grant program are named in

his honor. Since 1979, John A. Knauss Marine Policy Fellowships

have been awarded to hundreds of graduate students interested in

applying their training as oceanographers to the service of federal

agencies focused on ocean, coastal, and Great Lakes resources. It

is fair to say that his efforts have not only helped shape graduate

programs in ocean sciences, but have also opened many doors for

graduates of those programs.

John Knauss inspired our generation. What are we doing to

inspire and prepare the next generation? Are our graduate stu-

dents prepared to meet the science goals outlined in the recent

report Sea Change: 2015–2015 Decadal Survey of Ocean Sciences

and the needs of public scholarship, including outreach and edu-

cation? Are we giving these students the leadership and commu-

nication skills they need for careers in industry and the govern-

ment? In short, are we serving our students well? If not, perhaps

we also need a sea change in graduate education. Please con-

sider attending the TOS Town Hall at the 2016 Ocean Sciences

meeting where there will be a discussion focused on the future

of graduate education in ocean sciences. The conversation will

be enriched by many voices.

More than what we write or say about John Knauss, the most

fitting tribute to his legacy is to continue his tradition of con-

tributing to the ocean sciences community. Thinking carefully

about how we educate the next generation of oceanographers is

a step in that direction. One might call it an opening pitch. Few

of us will go the distance that John did, but he certainly provides

inspiration to all of us to step to the mound for a few innings and

pitch some new ideas.

FROM THE PRESIDENT

Oceanography | Vol.28, No.4

COMMENTARY

Bathymetric Extent of Recent Trawl Damage to the

Seabed Captured by an ROV Transect in the Alboran Sea

By Michael L. Brennan, Miquel Canals, Dwight F. Coleman, James A. Austin Jr., and David Amblas

Bottom trawl fishing is among the most destructive anthropogenic pressures acting

on benthic ecosystems, but the full extent of the damage is undocumented because

of the limited number of deep-sea observations of impacted regions (e.g., Brennan

et al., 2012, 2016). As part of its continuing ocean exploration mission, in 2011,

E/V Nautilus conducted a remotely operated vehicle (ROV) survey along a tran-

sect in a submarine canyon in the Mediterranean’s Alboran Sea off southern Spain

at depths ranging from 1,200 m to <300 m (Coleman et al., 2012). This exploration

along the South Alboran Ridge offered the opportunity to directly observe with

video the bathymetric extent and intensity of recent trawling damage to the seafloor

in this area. This dive revealed large furrows running in multiple directions caused

by trawl doors scraping across the seabed. Little biological activity was evident in

the depth ranges where these scars were observed. The destructive nature of bot-

tom trawl fishing should be viewed with the same public affront as subaerial clear-

cutting of forests and strip-mining. The only difference is that the ocean hides trawl

damage from the public eye. The more we explore the deep sea, repeatedly map the

seafloor with sonar, and observe the seabed and its ecosystems with video captured

by ROVs, the greater we can understand the full impacts of trawling.

The deleterious and nonselective damage that trawling operations cause to the

seabed has been a subject of concern and debate among ecologists and fisheries man-

agers for decades (e.g., Caddy, 1973; Jones, 1992; DeAlteris et al., 1999; Demestre

et al., 2015). Bottom trawls have a long-lasting impact beyond their removal of

large quantities of fish from the ecosystem, including bycatch. Trawling destroys

benthic habitats and hard ground for invertebrates, smooths over seabed morphol-

ogy, and resuspends sediments (e.g., Watling and Norse, 1998; Ivanović et al., 2011;

De Juan and Demestre, 2012; Lucchetti and Sala, 2012; Norse et al., 2012; Martín

et al., 2014a). In the Mediterranean, the trawl fleet works along both the conti-

nental shelf and the continental slope. Trawls catch many species, although only

some of them are targeted, including blue whiting (Micromesistius poutassou), hake

(Merluccius merluccius), red mullet (Mullus spp.), octopus (Octopus vulgaris and

FIGURE  1. The ROV transect began at

nearly 1,200 m on flat, muddy seabed, with

small mounded burrows and clear bioturba-

tion. Below 850 m, no trawl marks are evi-

dent. Macrofauna, including rattail fish, sea

urchins, crabs, and blackmouth catshark, were

observed in the area.

FIGURE  2. At 0530 GMT, Nautilus crossed

paths with a trawling vessel and caused the

team to slow the ROV transect. When the vehi-

cles reached the area the where the fishermen

were operating, fresh trawl marks were visi-

ble on the seabed. New trawl marks are criss-

crossed with older scars, although all appear

recent, with rectangular-shaped edges rather

than the U-shaped scars that develop once

they become partially filled in with sediment.

FIGURE 4. This picture of fresh, deep trawl fur-

rows in the sediment shows larger clumps of

sediment that have settled next to the scar.

Smaller particles are resuspended into the

water column and can be transported further

downslope as a sediment cloud caused by the

turbulence of the weighted net and gear pass-

ing by (Jones, 1992; Puig et al., 2012).

FIGURE 5. Isolated bedrock outcrops com-

monly found on flatter slopes create habitat for

a variety of fauna that live on and around them.

Here, an outcrop is inhabited by corals as well

as a siphonophore and a visiting Conger eel

(Conger conger). Both of the latter were com-

monly seen during this transect.

FIGURE 3. Many ridges in the sediment were

observed during the ROV transect when mov-

ing upslope; steeper terrain indicates slope fail-

ures. Trawl operations can smooth over such

sedimentary features and also trigger slope

failures, as has been noted in the Black Sea

(Brennan et al., 2013).

1,187 m

823 m

814 m

781 m

692 m

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