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
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Introducing the
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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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Contributing Writer
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Oceanography
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to disseminate knowledge of oceanography and
its application through research and education, to
promote communication among oceanographers,
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building across all the disciplines of the field.
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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