Oceanography | June 2022
Oceanography
THE OFFICIAL MAGAZINE OF THE OCEANOGRAPHY SOCIETY
VOL. 35, NO. 1, JUNE 2022
OCEANS ACROSS THE SOLAR SYSTEM
Oceanography | Vol.35, No.1
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Oceanography | June 2022
contents
VOL. 35, NO. 1, JUNE 2022
SPECIAL ISSUE ON OCEANS ACROSS THE SOLAR SYSTEM
10
Planetary Oceanography: Leveraging Expertise Among Earth and
Planetary Science
By C.R. German, K.R. Arrigo, A.E. Murray, and A.R. Rhoden
16
Ocean System Science to Inform the Exploration of Ocean Worlds
By C.R. German, D.K. Blackman, A.T. Fisher, P.R. Girguis, K.P. Hand, T.M. Hoehler,
J.A. Huber, J.C. Marshall, K.R. Pietro, J.S. Seewald, E.L. Shock, C. Sotin,
A.M. Thurnherr, and B.M. Toner
23
Leveraging Earth Hydrosphere Science in the Search for Life on
Ocean Worlds
By T.M. Hoehler, J.S. Bowman, K.L. Craft, P.A. Willis, and D.P. Winebrenner
30
Defining and Characterizing Habitable Environments in Ocean
World Systems
By J.B. Glass, H.M. Dierssen, C.R. Glein, B.E. Schmidt, and D.P. Winebrenner
39
Research in Analog Environments to Enable Studies of Ocean Worlds
By K. Arrigo
45
Applying Understanding of Earth Systems, Including Climate Change,
to Exploration of Other Ocean Worlds
By J.M. Grebmeier
54
Oceans Across the Solar System and the Search for Extraoceanic Life:
Technologies for Remote Sensing and In Situ Exploration
By V. Chirayath, E. Bagshaw, K. Craft, H. Dierssen, D. Lim, M. Malaska, O. Pizarro,
S. Purkis, D. Schroeder, P. Sobron, S. Waller, and D. Winebrenner
66
A Young Scientist’s Perspective on the Future of Ocean Worlds Research
By A. Kleinman
REGULAR ISSUE FEATURES
68
Gender Differences in NSF Ocean Sciences Awards
By I.D. Lima and J.E. Rheuban
ROGER REVELLE COMMEMORATIVE LECTURE
76
A Generational Shift in Ocean Stewardship
By A. Giron-Nava and H. Harden-Davies
54
45
16
23
Oceanography | June 2022
Oceanography | Vol.35, No.1
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SPECIAL ISSUE GUEST EDITOR
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Ashley Kleinman, NASA
DEPARTMENTS
03
QUARTERDECK. Oceanography Considers Oceans Across the Solar System
By E.S. Kappel
05
FROM THE TOS JEDI COMMITTEE. Science in Service of Our Communities
By M. Behl
07
RIPPLE MARKS. High-Stakes Mudbank Chase: At Low Tide, US Southeast
Dolphins “Beach” Their Prey
By C.L. Dybas
81
THE OCEANOGRAPHY CLASSROOM. Co-Creating Learning in Oceanography
By M.S. Glessmer and K. Daae
84
CAREER PROFILES. Willy Goldsmith, Executive Director, American Saltwater
Guides Association | Tye L. Kindinger, Research Marine Biologist, Ecosystem
Sciences Division, NOAA Pacific Islands Fisheries Science Center
On the Cover. Artistic rendering of ocean
worlds. Illustration by Jenny Mottar, NASA
This section of Oceanography provides an outlet for short peer-reviewed papers that describe novel
approaches to multidisciplinary problems in oceanography. These provocative papers will pres-
ent findings that are synthetic by design and have the potential to move the field of oceanogra-
phy forward or in new directions. The Associate Editor overseeing Breaking Waves is Ian Brosnan
(ian.g.brosnan@nasa.gov). Authors should submit a brief email to Dr. Brosnan that outlines their ideas
for papers prior to actual manuscript preparation. For more information, see the Author Guidelines at:
https://tos.org/oceanography/guidelines
Breaking Waves CALL FOR MANUSCRIPTS
Oceanography | Vol.35, No.1
Oceanography | June 2022
WITH THIS SPECIAL ISSUE, I am pleased to be able to bring to
Oceanography readers something a little different from the usual fare.
Instead of focusing on the wonders of Earth’s ocean, articles in this
special issue ask you to consider how ocean scientists’ knowledge and
skills might apply to studies of ocean worlds beyond our own, such
as Jupiter’s moon Europa, Saturn’s moons Enceladus and Titan, and
Neptune’s moon Triton.
Articles discuss how ocean system science—a combination of mod-
eling, laboratory experimentation, and observations—can be used to
predict what processes may act within ocean worlds. Other articles con-
sider how studying extreme environments on Earth, such as the thick
ice at the poles or hydrothermal vents on the seafloor, may provide
insights into whether and where life may exist in other ocean worlds.
Questions posed are: What constitutes habitability in an ocean world
environment? What laboratory and modeling approaches can we use to
investigate habitability in ocean worlds that are currently inaccessible?
The panoply of sophisticated robotic platforms, samplers, and sen-
sors used to explore Earth’s deep ocean and ice sheets are valuable test-
ing grounds for technologies that might be useful to our planetary
science colleagues. The complex expeditions that deploy ocean instru-
ments, while still expensive, come at a far lower cost, and are completed
in far less time, than investigations conducted in extraterrestrial ocean
worlds. Some of the satellite and other airborne sensors refined over
decades to gather a wide variety of data concerning our ocean may be
used on upcoming missions to ocean worlds.
Ocean scientists have made great progress in understanding the
complex and interconnected geological, chemical, biological, and phys-
ical processes that act in Earth’s ocean by working collaboratively across
disciplinary boundaries. Close partnerships among ocean, Earth, cryo-
sphere, and other geoscientists and with our planetary science col-
leagues will no doubt provide additional insights into the workings of
Earth’s ocean—as well as those of oceans across our solar system.
ARTICLE DOI
https://doi.org/10.5670/oceanog.2021.418
QUARTERDECK
OCEANOGRAPHY CONSIDERS
OCEANS ACROSS THE
SOLAR SYSTEM
Ellen S. Kappel, Editor
In this Oceanography section, contributing
authors share all of the relevant information
on a homemade sensor or instrument so that
others can build, or build upon, it. The short
articles also showcase how this technology
was used successfully in the field.
Call for Contributions
Oceanography guest editors Melissa Omand
and Emmanuel Boss are seeking contribu-
tions to DIY Oceanography. Contributions
should include a list of the materials and
costs, instructions on how to build, and any
blueprints and codes (those could be depos-
ited elsewhere). See Oceanography’s Author
Guidelines page for detailed information on
submission requirements.
https://tos.org/oceanography/guidelines
See the Collection
Go to the DIY Oceanography web page to
view the complete collection of articles.
• pySAS: Autonomous Solar Tracking
System for Surface Water Radiometric
Measurements
• An Optical Imaging System for Capturing
Images in Low-Light Aquatic Habitats Using
Only Ambient Light
• A Simple and Inexpensive Method for
Manipulating Dissolved Oxygen in the Lab
• The Pressure of In Situ Gases Instrument
(PIGI) for Autonomous Shipboard
Measurement of Dissolved O2 and N2 in
Surface Ocean Waters
• Inlinino: A Modular Software Data Logger
for Oceanography
https://tos.org/diy-oceanography
Oceanography | Vol.35, No.1
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Oceanography contains peer-reviewed articles that chronicle
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Oceanography | Vol.35, No.1
Oceanography | June 2022
FROM THE TOS JEDI COMMITTEE
Science in Service of Our Communities
By Mona Behl
IN THE GOLDEN ISLES of Georgia, the
Gullah art of braiding sweetgrass into bas-
kets can be traced back over 400 years to
its West African roots. This skill is passed
on from generation to generation, pre-
serving the oral history, sovereignty, and
culture of the Gullah people. Local and
indigenous coastal communities, like the
Gullah-Geechee, have a deep connection
with their natural environment as they
depend on forests, fisheries, and wildlife
resources for their livelihood and culture.
These frontline communities are also
facing a complex web of challenges that
include rising sea levels, coastal erosion,
saltwater intrusion, encroaching develop-
ment and increasing property taxes, and
loss of fisheries and other coastal liveli-
hoods. As communities develop strate-
gies to address these complex challenges,
they need access to place-based research
and education that is unique to their peo-
ple, culture, and ecology.
Scientists have a responsibility (Hooke,
2015) to support their local and indige-
nous communities by providing data and
scientific information that make sense
to them, and to do so with humility and
respect. While climate change is a global
phenomenon, it is at the local scale that
the impacts are most felt. Because the
impacts are local, people who are most
invested in finding solutions are also
from local communities. This includes
students, community leaders, tribal and
local governments, educational insti-
tutions,
nonprofits,
businesses,
and
faith- based institutions, among others.
Scientists must invest time in building
trust and relationships with our commu-
nity members. By listening to insights
that local knowledge holders share about
their local ecology and their relationship
with the environment, we can understand
what matters to the community and how
we might help. We can approach our
research as an opportunity for knowledge
exchange and capacity building within
local communities. By collaborating with
communities, we can co-produce solu-
tions. Co-production not only builds
trust in data, processes, and partners but
also diversifies and democratizes science.
Relationship building with communi-
ties does not always have to begin from
scratch. Our university- based agricul-
tural extension and Sea Grant programs
already have long-standing and trusted
relationships with local and indigenous
communities. We can collaborate closely
with these programs to identify import-
ant issues and needs within communi-
ties and formulate research questions in
appropriate social contexts. We can refine
our research questions and hypotheses
by incorporating traditional and ecolog-
ical knowledge to provide novel insights.
Programs like the American Geophysical
Union’s Thriving Earth Exchange match
scientists with community leaders and
funders to solve local environmen-
tal problems. Scientists can also collab-
orate with programs like the National
Oceanic and Atmospheric Administra-
tion’s Regional Integrated Sciences and
Assessments program to help build com-
munity resilience to weather and climate
events. We can work closely with K–12
schools, aquariums, zoos, and museums
to immerse people in informal learning
environments. We should seek collabo-
rations with scientists and practitioners
outside of our own disciplines and learn
to do so effectively (Bennett and Gadlin,
2012). And our collaborations should not
be limited to colleagues at R1 universi-
ties but must be extended to researchers
at minority-serving institutions as well
(NASEM, 2019b). Lastly, we must serve
as a resource to our political leaders and
learn how to responsibly engage in the
policy process.
In addition to doing socially relevant
research, we must assist our students in
forming habits of heart and mind that pre-
pare them to contribute to the betterment
of the world. This can be done by provid-
ing culturally relevant education (Ladson-
Billings, 1995) and mentorship (NASEM,
2019a), and engaging them in intriguing
local problems. When we create learning
and working environments where people
from diverse backgrounds get seats at the
table, and are heard, seen, and are recog-
nized for their contributions, we instill a
sense of belonging. This sense of belong-
ing is directly linked to improved educa-
tional outcomes, performance, and reten-
tion (e.g., Johnson, 2012). By creating
more supportive and inclusive environ-
ments, we can both increase the diversity
of our scientific workforce and prepare
students for a variety of career pathways
in STEM professions (Batchelor et al.,
2021). We must also increase our own
awareness and understanding of sys-
temic racism and injustices in science and
beyond, and take immediate measures to
address these issues.
In her book Braiding Sweetgrass, Pota-
watomi botanist Robin Wall Kimmerer
writes, “Being naturalized to place means
to live as if this is the land that feeds you,
as if these are the streams from which you
drink, that build your body and fill your
spirit. To become naturalized is to know
Oceanography | Vol.35, No.1
OCEANOGRAPHY
RESOURCES
that your ancestors lie in this ground. Here
you will give your gifts and meet your
responsibilities. To become naturalized is
to live as if your children’s future matters,
to take care of the land as if our lives and
the lives of all our relatives depend on it.
Because they do.”
Let’s become naturalized to the places
where we live and work by listening to,
learning from, and supporting the people
in our communities. And let’s make sure
that we do so in a sustained, respectful,
and consequential manner.
REFERENCES
Batchelor, R.L., H. Ali, K.G. Gardner-Vandy, A.U. Gold,
J.A. MacKinnon, and P.M. Asher. 2021. Reimagining
STEM workforce development as a braided river.
Eos 102, https://doi.org/10.1029/2021EO157277.
Bennett, L.M., and H. Gadlin. 2012. Collaboration and
team science: From theory to practice. Journal of
Investigative Medicine 60(5):768–775.
Hooke, W. 2015. Reaffirming the social con-
tract between science and society. Eos 96,
https://doi.org/ 10.1029/2015EO026333.
Johnson, D.R. 2012. Campus racial climate per-
ceptions and overall sense of belonging among
racially diverse women in STEM majors. Journal
of College Student Development 53(2):336–346,
https://doi.org/ 10.1353/csd.2012.0028.
Ladson-Billings, G. 1995. But that’s just good teach-
ing! The case for culturally relevant pedagogy.
Theory into Practice 34(3):159–165, https://doi.org/
10.1080/00405849509543675.
NASEM (National Academies of Sciences,
Engineering, and Medicine). 2019a. The Science
of Effective Mentorship in STEMM. The National
Academies Press, Washington, DC, 306 pp.,
https://doi.org/10.17226/25568.
NASEM. 2019b. Minority Serving Institutions:
America’s Underutilized Resource for
Strengthening the STEM Workforce. The National
Academies Press, Washington, DC, 254 pp.,
https://doi.org/10.17226/25257.
AUTHOR
Mona Behl (mbehl@uga.edu) is Associate Director,
Marine Extension and Georgia Sea Grant, University
of Georgia, Athens, GA, USA, and a member of the
TOS JEDI Committee.
ARTICLE CITATION
Behl, M. 2021. Science in service of our communi-
ties. Oceanography 35(1):5–6, https://doi.org/10.5670/
oceanog.2021.403.
COPYRIGHT & USAGE
This is an open access article made available under
the terms of the Creative Commons Attribution 4.0
International License (https://creativecommons.org/
licenses/by/4.0/), which permits use, sharing, adapta-
tion, distribution, and reproduction in any medium or
format as long as users cite the materials appropri-
ately, provide a link to the Creative Commons license,
and indicate the changes that were made to the
original content.
Navigating Grad School
This new Oceanography column provides guidance and advice for
grad students.
• Envisioning and Writing a Thesis Proposal > https://doi.org/
10.5670/oceanog.2021.316
• Finding a Thesis Topic > https://doi.org/10.5670/oceanog.2022.211
The Oceanography Classroom
A recurring column in Oceanography, The Oceanography
Classroom provides guidance and insights into teaching
undergraduate and graduate classes in the ocean sciences.
> https://tos.org/classroom
Career Profiles
To date, Oceanography has posted nearly 100 career profiles of
marine scientists. These profiles discuss the career paths taken,
decisions made along the way, and job satisfaction, and provide
advice on job searches. > https://tos.org/career-profiles
Hands-On Oceanography
Hands-On Oceanography articles provide peer-reviewed
activities appropriate for use in undergraduate and/or graduate
oceanography classes.
> https://tos.org/hands-on-oceanography
TOS Grad Student/Early Career Resources Page
On this page you will find the TOS Twitter feed, Oceanography
Student News, and links to fellowship, fieldwork, and employment
opportunities, as well as links to helpful articles and websites.
> https://tos.org/opportunities
Ocean Education Articles
Ocean Education articles describe an undergraduate or graduate
program, often funded by government agencies, designed to aid in
a specific educational outcome.
> https://tos.org/ocean-education-articles
FOR STUDENTS
FOR EDUCATORS
Oceanography | Vol.35, No.1
Oceanography | June 2022
High-Stakes Mudbank Chase
AT LOW TIDE, US SOUTHEAST DOLPHINS “BEACH” THEIR PREY
BY CHERYL LYN DYBAS, PHOTOS BY ILYA RASKIN
Captain Sam’s Spit, a sandy inlet at the
southern end of South Carolina’s Kiawah
Island, moves with the winds, the waves,
the tides. Sand grain by sand grain, it
erodes and accretes, erodes and accretes.
The spit’s shifting beaches and mud-
flats are important to species like piping
plovers, diamondback terrapins, and
Atlantic bottlenose dolphins. And to the
dolphins’ prey, mullets. The fish leap out
of the water in straight, clean slices to
escape their predators.
Mullets aren’t the only animals jump-
ing at Captain Sam’s Spit. The inlet is a
showcase for a low-tide bottlenose dol-
phin behavior called strand feeding. It
starts when two or more dolphins work
together to herd a school of mullets into
shallow water and toward the shoreline, in
this case the muddy banks of the Kiawah
River that runs between South Carolina’s
Kiawah and Seabrook islands.
It’s early November when Captain Jake
Feary, assistant director of outdoor pro-
grams at the Kiawah Island Golf Resort,
ferries us in a Boston Whaler to a spot just
off Captain Sam’s Spit. Slowing to an idle,
we quietly bob in small waves, waiting for
the display to start. Pelicans glide over-
head, alerting us to fish below. Where pel-
icans go, so, too, go the dolphins.
Just off the starboard bow, water sud-
denly splashes in all directions. Fins
appear, swirling in tighter and tighter
circles. “The show is about to begin,”
announces Feary. “The dolphins are
herding the fish into a ball they can drive
ashore, then they’ll surge onto the mudflat
right behind them.”
Dolphins corral the fish in a circle of
bubbles left in their wakes, pushing their
prey ever closer to the shore’s edge. All
at once, the dolphins rush the mudbank,
forcing the flopping fish ahead of them. A
wave of water from the lunging dolphins
carries the fish forward.
The dolphins are right on their tails,
heaving as much as two-thirds of their
bodies onto the mudflat. Their prey is
now stuck on the bank, unable to escape.
When almost every fish has become the
dolphins’ breakfast, lunch, or dinner, they
shimmy back into the shallows, there to
search for another school of fish to strand.
ONLY IN THE LOWCOUNTRY
Kiawah residents and visitors are lucky
to witness the spectacle, Feary says.
Dolphin strand feeding happens only
in the Lowcountry and a very few other
places around the globe. Captain Sam’s
is the sole location where strand feeding
doesn’t require a boat to spot. Depending
on the time of day and therefore tide, peo-
ple can watch by walking out to flats along
the Kiawah River.
“Along the East Coast, strand feeding can
be observed only in the tidal creeks and
marshes of South Carolina and Georgia,”
writes Cara Gubbins in The Dolphins of
Hilton Head.
In South America, dolphins strand feed
in Ecuador’s Gulf of Guayaquil. There,
strand feeding occurs at very low tides
in the interior channels of mangroves.
Extreme low tides, such as those at the
full moon, uncover wide mudflat beaches,
creating good conditions for strand feed-
ing, report Pedro Jimenez and Juan Jose
Alava in the Latin American Journal of
Aquatic Mammals.
“Groups of bottlenose dolphins, ranging
RIPPLE MARKS: THE STORY BEHIND THE STORY
Oceanography | June 2022
Oceanography | Vol.35, No.1
from two to eight individuals, were
observed first being very active and tar-
geting fish in the middle of a channel
and nearby mudflats and mangroves,”
Jimenez and Alava write. “Then they
started approaching and chasing their
prey, trapping them against the mud-
banks, onto which at least one or two dol-
phins stranded each time and captured
the prey successfully.”
What, if any, signals the dolphins use to
coordinate their bow wave is unknown.
“No one has observed any definitive phys-
ical signal that always precedes strand
feeding, nor has any acoustic signal (whis-
tle or echolocation click) been reliably
associated with strand feeding,” Gubbins
states in The Dolphins of Hilton Head.
“There might be a producer-scrounger
effect: One dolphin initiates the rush, judg-
ing the correct time and place, and nearby
dolphins, with their quick reflexes, simply
follow the leader.”
Two dolphins strand feeding together
can make a bigger wave as they rush the
shore, beaching more fish.
At Captain Sam’s, the behavior hap-
pens every day. With bottlenose dolphins
weighing almost 227 kilograms and mullet
just centimeters long, the dolphins need
to eat a lot of fish. That translates to hours
of strand feeding.
“These dolphins are part of the
Charleston estuarine population,” says
Lauren Rust, executive director of the
Lowcountry Marine Mammal Network.
“They live in brackish waters year-round
and spend a majority of their time in small
areas—their home ranges.” That includes
the Kiawah and Stono Rivers. The Stono
flows southwest of Charleston, South
Carolina, its channel running between
the mainland and Wadmalaw Island and
Johns Island.
“We’ve identified six or seven dolphins
that strand feed pretty consistently in the
Kiawah River,” says Rust. The dolphins
usually feed in groups of three, “but I’ve
seen up to five,” Rust recalls, “and some-
times a single animal. Sometimes they
feed once or twice a day, other days up
to 37 times.”
In the Charleston area, strand feeding
happens year-round, but slows in winter
when mullets go offshore.
The best time to see strand feeding at
Captain Sam’s Spit, according to Feary, is
the four-hour period around low tide. Then
the Kiawah River’s main channel is at its
most shallow and most narrow. The water
level is below that of the marsh grasses,
so mullets are more visible to the dol-
phins. They strand feed on both sides of
the river, wherever there are mudbanks.
MEET THE STRAND
FEEDING DOLPHINS
To learn more about the dolphins’ unusual
feeding technique, the towns of Kiawah
and Seabrook are supporting a bottle-
nose dolphin monitoring program coordi-
nated by the Lowcountry Marine Mammal
Network. Rust has recruited more than
20 volunteers to monitor each side of
the Kiawah River at Captain Sam’s Spit
every day during the summer months,
and on weekends and holidays the rest
of the year.
Data collected so far show that there
are about 25 resident dolphins in the
Kiawah River, with more than a dozen
strand feeders.
Tagging and genetic studies have
revealed information about the diet,
age, sex, and health of the dolphins.
Researchers are using photos of the dol-
phins’ dorsal fins, comparing each fin to
those catalogued in a database, to track
the cetaceans over time. “Identifying
individuals allows us to learn about their
home ranges, family units, new calves,
and associations between individuals,”
Rust says. “That information is important
to understanding the health of the popu-
lation and its habitat.”
One mother dolphin in the Kiawah River,
KoKo, taught her calf, Kai, to strand feed.
“On some days,” says Rust, “the pair spent
more than 20% of its time in the inlet play-
ing, feeding, and likely nursing.” Biologists
have seen at least three mother-calf pairs
frequenting the area, so it may be a safe
place for mothers to bring their young.
A dolphin named Step “is one of the
longest- studied near Charleston, having
first been noted in 1995,” says Rust. “Since
then, she has been spotted more than
70 times in the Stono River.” Low Country
Marine Mammal Network staff members
have also seen her in the Kiawah River, and
have confirmed that she’s a strand feeder.
Researchers spotted her there with at
least five calves. Two, named High Scoops
and Rosie, are strand feeders themselves.
The calves are 16 years old and 11 years
old, respectively, and are independent
from Step. But they’ve been glimpsed