Ecological and biological studies of ocean rafting: Japanese tsunami marine debris in North America and the Hawaiian Islands

Full text

Aquatic Invasions (2018) Volume 13, Issue 1: 1–9
DOI:
https://doi.org/10.3391/ai.2018.13.1.01
© 2018 The Author(s). Journal compilation © 2018 REABIC
Special Issue: Transoceanic Dispersal of Marine Life from Japan to North America and
the Hawaiian Islands as a Result of the Japanese Earthquake and Tsunami of 2011
1
Introduction to Special Issue
Ecological and biological studies of ocean rafting: Japanese tsunami
marine debris in North America and the Hawaiian Islands
James T. Carlton
1,2,
*
, John W. Chapman
3
, Jonathan B. Geller
4
, Jessica A. Miller
3
, Gregory M. Ruiz
5
,
Deborah A. Carlton
2
, Megan I. McCuller
2
, Nancy C. Treneman
6
, Brian P. Steves
5
, Ralph A. Breitenstein
7
,
Russell Lewis
8
, David Bilderback
9
, Diane Bilderback
9
, Takuma Haga
10
and Leslie H. Harris
11
1
Maritime Studies Program, Williams College-Mystic Seaport, Mystic, Connecticut 06355, USA
2
Williams College, Williamstown MA 01267, USA
3
Department of Fisheries and Wildlife, Oregon State University, Hatfield Marine Science Center, 2030 SE Marine Science Drive,
Newport, Oregon 97365, USA
4
Moss Landing Marine Laboratories, Moss Landing, California 95039, USA
5
Smithsonian Environmental Research Center, Edgewater, Maryland 21037, USA
6
Oregon Institute of Marine Biology, Charleston, Oregon 97420, USA
7
College of Earth, Oceanic and Atmospheric Sciences in Corvallis, Oregon State University, 104 CEOAS Administration Building
Corvallis, OR 97331, USA
8
P.O. Box 867, Ocean Park, Washington 98640, USA
9
3830 Beach Loop Drive SW, Bandon, Oregon 97411, USA
10
National Museum of Nature and Science, 4-1-1 Amakubo, Tsukuba, Ibaraki 305-0005, Japan
11
Natural History Museum of Los Angeles County, 900 W Exposition Blvd., Los Angeles, California 90007, USA
Author e-mails: james.t.carlton@williams.edu (JTC), john.chapman@oregonstate.edu (JWC), geller@mlml.calstate.edu (JBG),
Jessica.Miller@oregonstate.edu (JAM), ruizg@si.edu (GMR), debcarlton987@gmail.com (DAC), mccullermi@gmail.com (MIM),
ntreneman@gmail.com (NCT), stevesb@si.edu (BPS), ralph.breitenstein@gmail.com (RAB), cheriruss55@centurytel.net (RL),
ddbilderback@gmail.com (DB), haga@kahaku.go.jp (TH), exogone@hotmail.com (LHH)
*
Corresponding author
Received: 12 January 2018 / Published online: 15 February 2018
Co-Editors’ Note:
This is one of the papers from the special issue of Aquatic Invasions on “Transoceanic Dispersal of Marine Life from
Japan to North America and the Hawaiian Islands as a Result of the Japanese Earthquake and Tsunami of 2011." The
special issue was supported by funding provided by the Ministry of the Environment (MOE) of the Government of Japan
through the North Pacific Marine Science Organization (PICES).
The potential ecological and biogeographic signi-
ficance of the Great East Japan Earthquake and
Tsunami of March 11, 2011 was initially unforeseen
for the Eastern North Pacific Ocean. It was not until
June 5, 2012 when possible impacts to the marine
biota of North America became evident. Early that
morning, beach walkers on the central Oregon coast
discovered a massive floating dock densely covered
with marine life (Figure 1). The dock was soon
identified as having been lost from the fishing port
of Misawa in Aomori Prefecture in northeastern
Honshu (Table 1 herein; see also Carlton et al. 2017,
Figure S1). We designated this dock as Japanese
Tsunami Marine Debris Bio-Fouling object number 1
(JTMD-BF-1). The dock was informally named
“Misawa 1,” after we learned that four identical 20
meter long structures had been lost from this port
during the tsunami.
Fortuitously, Misawa 1 landed only 5 km from a
marine science research laboratory, the Hatfield Marine

J.T. Carlton et al.
2
Figure 1. Upper photo, “Misawa 1”, a fisheries dock from the Port of Misawa, Aomori Prefecture, washed away March 11, 2011, and
landing on Agate Beach, Newport, Oregon, June 5, 2012. Lower left, sea anemones (Metridium dianthus) from Japan, along with barnacles
(Semibalanus cariosus) and mussels (Mytilus galloprovincialis) on Misawa 1; lower right, S. cariosus, M. galloprovincialis, and the barnacle
Megabalanus rosa. Photographs by Jessica A. Miller.
Science Center (HMSC), in Newport, Oregon. Within
a few hours of the dock’s discovery, HMSC marine
ecologists Jessica Miller, John Chapman, and Gayle
Hansen sampled the dock’s biofouling community.
More than 130 living species of Japanese invertebrates,
protists, and algae were collected (Carlton et al. 2017;
Hanyuda et al. 2017; G. Hansen, personal communi-
cation 2017). These samples represented only a small
fraction of the dock’s more than 75 square meters of
fouling. The 104 species of invertebrates and protists
(Table 1) detected aboard, while an underestimate of
the total species pool, were to represent fully one-third

Ecological and biological studies of ocean rafting
3
Table 1. Examples of some notable Japanese tsunami marine debris (JTMD) objects, relative to patterns of biodiversity and geography.
JTMD-Bio-Fouling (BF)
object number, type,
origin in Japan if known,
and size (in meters)1
L length
H height
W width
Location and date of
landing (all in U.S.A.)2
WA Washington
OR Oregon
CA California
HI Hawaiian Islands
Living Japanese
fauna
(number of species;
from Carlton et al.
2017, except as
noted)
Comments
BF-1: Fisheries floating
dock (Misawa, Aomori
Prefecture)
20.1 L, 2.1 H, 5.8 W
OR: Lincoln Co.:
Newport: Agate Beach
5 June 2012
104 (95 invertebrates,
9 protists) 3
Named “Misawa 1”, this was one of four identical
docks torn away by the tsunami from the Port of
Misawa. It was detected drifting southward past
Yaquina Head on the afternoon of June 4, 2012 by
Cheryl A. Horton of Oregon State University, and
then found ashore to the immediate south on the
morning of June 5. On June 5-7, the dock biota,
including masses of the kelp Undaria pinnatifida
(Harvey) Suringar, 1853 and hundreds of thousands
of mussels (predominately Mytilus galloprovincialis),
were scraped off and buried on the high beach. The
dock was cut up and removed from the beach July–
August 2012. Still alive on the dock on August 3,
2012, inside the seaward bumpers, were the barnacle
Megabalanus rosa and the mussel Mytilus
galloprovincialis. In Science for October 27, 2017
(vol. 358, no. 6362, page 454), a photograph of a
living oyster (Crassostrea gigas) and of living
barnacles (M. rosa and Semibalanus cariosus) from
BF-1 was published.4 Sections of Misawa 1 are on
outside display at the Hatfield Marine Science Center
in Newport, Oregon and on the Newport waterfront.
Fisheries floating dock
(Misawa, Aomori
Prefecture)
20.1 L, 2.1 H, 5.8 W
HI: drifting past
Moloka‘i and Maui
17–19 September 2012
unknown “Misawa 2” drifted at sea offshore of Maui and
Moloka‘i; a local vessel fished approximately 2268 kg
of mahi-mahi (Coryphaena hippurus) from under and
around the dock, which had acted as a fish aggregating
device. The dock continued west past the Islands; it
has not been seen again as of January 2018. No BF
number was assigned as this dock was not sampled.
BF-8: Fisheries floating
dock (Misawa, Aomori
Prefecture)
20.1 L, 2.1 H, 5.8 W
WA: Clallam Co.:
Olympic National Park
18 December 2012
51 (49 invertebrates,
2 protists)
“Misawa 3” was discovered drifting northward on
December 14, 2012, 30 km at sea northwest of Grays
Harbor WA, by the F/V Lady Nancy; it was then
found ashore, 100 km north, by a United States Coast
Guard helicopter crew on December 18 just south of
Mosquito Creek and north of Hoh Head, in the
Olympic National Park. A field team sampled the
dock on December 21. The marine life on the dock
was removed by scraping and bleaching, and by
removal of the biofouled fenders, on January 3–4,
2013 (Barnea et al. 2013). The dock was then cut up
and removed from the beach in March 2013.
“Misawa 4” has not been seen as of January 2018,
leaving the fate of that dock and “Misawa 2” (above)
unaccounted for.
BF-23: Vessel
9 L
OR: Lincoln Co.:
Gleneden Beach
5 February 2013
53 (50 invertebrates,
3 protists)
One of two vessels (see BF-40, below) that supported
the same approximate number of species as on the
much larger Misawa 3 (BF-8), above.
BF-40: Vessel Sai-shou
Maru (Rikuzentakata,
Iwate Prefecture) 6.4 L
WA: Pacific Co.: Long
Beach Peninsula: Long
Beach
22 March 2013
57 (52 invertebrates,
4 protists, 1 fish)
This vessel came ashore upright (rare for most JTMD
boats) with five living Japanese barred knifejaw fish
Oplegnathus fasciatus (Temminck & S chlegel, 1845)
in the stern wet well (Ta et al. 2018). The Sai-shou Maru
is on display at the Columbia River Maritime
Museum, Astoria, Oregon.

J.T. Carlton et al.
4
Table 1 (continued). Examples of some notable Japanese tsunami marine debris (JTMD) objects, relative to patterns of biodiversity and
geography.
JTMD-Bio-Fouling (BF)
object number, type,
origin in Japan if known,
and size (in meters)1
L length
H height
W width
Location and date of
landing (all in U.S.A.)2
WA Washington
OR Oregon
CA California
HI Hawaiian Islands
Living Japanese
fauna
(number of species;
from Carlton et al.
2017, except as
noted)
Comments
post-and-beam timber
(Japanese cedar)
5.5 L
CA: Santa Cruz Co.:
Santa Cruz: Three Mile
Beach, on the northern
shore of Monterey Bay
1 March 2015
unknown The farthest south documented JTMD item on the
Pacific coast of North America
(http://www.santacruzsentinel.com/article/NE/201503
03/NEWS/150309922; accessed January 2018). No
BF number was assigned, as this construction beam
was not sampled.
BF-356: Vessel (name
unknown) (Iwate
Prefecture)
7. 9 (originally 15.2) L
OR: 8 km offshore
(west) of Seal Rock
[16 km south of
Newport]
9 April 2015
22 (18 invertebrates,
2 protists, 2 fish)
One of two (the other being BF-40, above) JTMD
vessels arriving with living Western Pacific fish (this
vessel contained Japanese yellowtail jack Seriola
aureovittata Temminck & Schlegel, 1845 as well as
barred knifejaw Oplegnathus fasciatus). While most
Japanese vessels are composed largely of plastic and
metal, some, such as this vessel, also had wooden
components which supported shipworms.
BF-402: Vessel (name
unknown)
9 L
WA: Pacific Co: Long
Beach Peninsula:
Seaview
10 May 2015
45 (41 invertebrates,
4 protists)
Arriving 4 years and 2 months after the tsunami, this
vessel supported the largest diversity of bivalves of
any JTMD object. Seventeen living (and an additional
7 dead) bivalve species were aboard, showing a very
strong southern species acquisition signature (Carlton
et al. 2017). Of the 17 living bivalves, 7 occur only
south of the Boso Peninsula; all 7 dead species also
occur only south of the Boso Peninsula, suggesting
the transit to the Pacific Northwest was not
sustainable for many of the warmer water species.
BF-667: Rope and float
mass exceeding 15.3 m3
HI: Kauai: Kapa‘a
7 December 2016
13 invertebrates (see
Comments)
“The very best habitat for invasive species that I
recovered [in Hawaii] over (27) years was [this] huge
mass of ropes, nets, and more than 120 floats that
came ashore in Kapa‘a” in December 2016 (Carl
Berg, Surfrider Foundation, Kaua‘i, pers. comm. 16
October 2017). Only a very small area of BF-667 was
possible to sample (C. Berg, pers. comm., 2016). A
photograph of species from this rope-float mass was
on the cover of Science for September 29, 2017 (vol.
357, no. 6358).
1 For growth, reproduction, and structural and elemental (barium/calcium) shell analyses of the mussel Mytilus galloprovincialis on BF-1, 8,
23, 40, and other JTMD objects, see Miller et al. (2017).
2 Latitude and longitude coordinates (in decimal degrees) in Carlton et al. (2017), Supplementary Materials, Table S1.
3 Total number of species in JTMD-BF-1 (Misawa 1) differs from that (n = 96) shown in Carlton et al. (2017) due to recent updates,
including foraminifera (4 additional species, Finger 2018), sponges (2 additional, Elvin et al. 2018), and hydroids (1 additional, Choong et
al. 2018). In addition, a metagenomic analysis of BF-1 (see McCuller et al. 2018; Elvin et al. 2018; and Choong et al. 2018) revealed the
presence of the Japanese ascidian Styela clava (98.4% sequence match over 305b bp to GenBank KC905099 (New Zealand).
4 For a video of additional species on BF-1, see http://www.sciencemag.org/news/2017/09/japanese-tsunami-transported-hundreds-species-
united-states-and-canada-video-reveals. Included in this video are photographs of living barnacles (Megabalanus rosa), crabs
(Hemigrapsus sanguineus and Oedignathus inermis) and a sea star (Asterias amurensis).
of all the Japanese fauna that was to be documented
on JTMD over the next five years.
While Misawa 1 was not the first JTMD object to
reach North America, it was the first major arrival
available for biological sampling. Several months
earlier, in March and April 2012, a 40 meter long
Japanese fishing boat, the Ryou-un Maru (
漁運丸)
drifted into the coastal waters of North America
(Committee on Commerce, Science, and Transpor-
tation 2013). At about the same time other JTMD
objects were arriving in Alaska and Canada,
including a crated Harley-Davidson motorcycle from

Ecological and biological studies of ocean rafting
5
Miyagi Prefecture that came ashore on the British
Columbia coast (Billock 2016), and now resides in the
Harley-Davidson Museum in Milwaukee, Wisconsin.
In contrast, the Ryou-un Maru a decommissioned
vessel that had been awaiting disposal in Hachinohe,
only 20 km south of Misawa, now resides at the
bottom of the Pacific Ocean. In retrospect, it was a
harbinger of the Misawa 1 dock that would arrive 10
weeks later. Moored in the Port of Hachinohe, the
Ryou-un Maru may have carried a rich biofouling
community into the Northeast Pacific Ocean. Prior
to any sampling being feasible, however, the vessel
was sunk by the U. S. Coast Guard in more than
1800 meters of water 290 km off the coast of Alaska
(https://www.youtube.com/watch?v=C9HW5361bBs;
accessed January 2018).
Between June and December 2012, 15 additional
objects recognized as JTMD and available for sampling
came to our attention (we became aware in 2013 and
2014 of several other JTMD items collected in 2012;
Carlton et al. 2017, Table S2). These objects, found
in Washington, Oregon, California and the Hawaiian
Islands, as well as on Midway, ranged from small
buoys to vessels to another of the four Misawa docks
(Table 1). Based on this pulse of 2012 arrivals, we
established an informal network of private and public
personnel from Alaska to California and Hawaii to
facilitate timely notice of landings, establish samp-
ling protocols, and secure samples to be sent to our
laboratories. Further sampling, processing, analytical,
and data archive details are provided in Carlton et al.
(2017, and Supplementary materials, Materials and
Methods).
Over the next five years, we analyzed samples
and photographs from over 600 JTMD objects.
These objects were identified as JTMD based upon
identification marks, as well as on a broad suite of
historical, biological (bioforensic) and biogeographic
evidence (see Carlton et al. 2017, Supplementary
Materials, Materials and Methods). Underpinning
the identification of this sui generis debris pulse
from the Western to the Eastern Pacific Ocean are
the highly constrained temporal nature and geographic
origin of this megarafting event, which commenced
dramatically in 2012 and was declining by 2017.
Coupled with this is the observation that all identified
Japanese objects during this period were solely from
the tsunami-stricken coast north of Tokyo. If debris
had been arriving on a regular basis on Northeast
Pacific shores from Japan, independent of the tsunami,
before or during this period, rafted objects from a
broad region of the Japanese coast would have been
observed.
Several examples of notable JTMD objects,
relative to patterns of biodiversity and geography,
are presented in Table 1. Three of the four Misawa
docks were seen (and two acquired) in 2012; the
whereabouts of two docks remain unknown. Misawa 3
(BF-8) landed 6 months after Misawa 1 with appro-
ximately half the number (49 vs. 95) of invertebrate
species, possibly due to increased mortality during
the longer sea voyage. In the next 90 days, two
vessels (BF-23 and BF-40), both much smaller than
Misawa 3, arrived with on-board species diversity
rivaling that of Misawa 3, suggesting that these
vessels may also have had considerably more species
prior to departure from Japan.
One of the most highly publicized vessels (BF-40),
and thus better known JTMD arrivals, is the skiff
Sai-shou Maru (斎勝丸) which rafted across the ocean
right side up with living Japanese fish trapped in the
boat (Ta et al. 2018). The Sai-shou Maru was owned
by Katuo Saito of Rikuzentakata City and used for
abalone and sea urchin fishing. The Saito family,
whose daughter was lost in the tsunami, donated the
boat to the Columbia River Maritime Museum in
Astoria, Oregon, where it is now on display, with
some Japanese barnacles and bryozoans still attached.
A second and much larger vessel (BF-356, arriving
at half its original size) was discovered drifting
offshore off Oregon two years later with additional
Japanese fish aboard (Table 1; Craig et al. 2018).
More than four years after the tsunami, one vessel
(BF-402), which had rafted from the Tōhoku coast
south into tropical waters, arrived in Washington in
May 2015 with a remarkable 24 species of coastal
bivalves in the fouling community. Seven of the
warm-water species on the vessel had succumbed by
the time of their arrival in the cold waters of the
Pacific Northwest. In December 2016, nearly five
years after the tsunami, a mass of rope and buoys
(BF-667) from a Japanese oyster farm, and with
living species still aboard, landed in Kaua‘i, Hawaii.
BF-667 was so large that time and personnel resour-
ces permitted only a small sample of the associated
biota to be secured.
The sampled objects represent only a small fraction
of the debris field and associated Japanese biota that
arrived in North America and the Hawaiian Islands.
We presume that many millions of objects were
washed away from Japan, and that many thousands,
if not tens of thousands, of these objects arrived in
North America and in Hawaii. One outcome of
sampling only a small fraction of the debris is that
many JTMD-sourced species arriving on the Pacific
coast or in the Hawaiian Islands with the potential to
colonize were simply never detected (Carlton et al.
2017). Nevertheless, this research has provided
striking insight into the impressive diversity of
coastal species susceptible to ocean rafting, and their

J.T. Carlton et al.
6
unexpectedly long survival at sea. This includes several
groups of taxa, such as foraminiferans, sponges,
hydroids, bryozoans, peracarid crustaceans, and marine
insects, that passed through multiple generations.
The broad temporal and spatial biological patterns of
JTMD are presented in Carlton et al. (2017).
Contributions to the Knowledge of Japanese
and North Pacific Ocean Marine Biota
Of particular interest in the study of JTMD was the
discovery or resolution of at least 24 species of
invertebrates and algae that represent new records
for either all of Japan or the Japanese Pacific coast
(Table 2). Several of these species were resolved by
molecular genetic studies which also supported
morphological identifications or contributed addi-
tional sequences for selected taxa (Table 3). These
new records include the detection of a sponge,
Haliclona xena de Weerdt, 1986, originally described
from The Netherlands and thought to be introduced
to Western Europe, but whose provenance was
unknown prior to its discovery on JTMD. As noted
by Elvin et al. (2018), the determination of this
sponge as likely being native to the Northwest Pacific
is further in concert with the presence of nearly 30
other species of introduced Japanese invertebrates
and algae in The Netherlands.
At least seven new invertebrate and algal species
have been detected on JTMD to date, four of which
remain undescribed (Table 2). The bryozoan Bugula
tsunamiensis McCuller, Carlton and Geller, 2018 is
one of several new contributions to Japanese
bryozoology; along with the recognition of this new
Bugula, McCuller et al. (2018) elevate another
Japanese bryozoan, Bugula constricta Yanagi and
Okada, 1918, to full species status. Previous studies
on the introduced bryozoan Bugulina stolonifera
(Ryland, 1960) had determined that it had reached
Tokyo from southern locations by 2013, but its
presence on JTMD from the Aomori Prefecture
demonstrates it occurred considerably farther north
by 2011. Another bryozoan, Escharella hozawai
(Okada, 1929), last reported in 1929 when it was
first described in Japan, was re-discovered on JTMD
(McCuller and Carlton 2018).
As JTMD drifted across the ocean, indigenous
high seas species settled on debris items. These
included the pelagic gooseneck barnacle Lepas spp.,
the crabs Planes marinus Rathbun, 1914 and P. major
(MacLeay, 1838) and Plagusia spp., the polychaete
worm Amphinome rostrata, the amphipod Caprella
andreae Mayer, 1890, and the nudibranch Fiona pinnata
(Eschscholtz, 1831), as well as the oceanic bryozoans
Jellyella tuberculata (Bosc, 1802), Jellyella eburnea
(Hincks, 1891), and Arbopercula angulata (Levinsen,
1909). Two additional species are now newly added
to this neustonic-pleustonic biota. The red alga
Tsunamia transpacifica West, Hansen, Zuccarello
and Hanyuda, 2016 (West et al. 2016) was described
from plastic JTMD arriving in Oregon and Washington.
Choong et al. (2018) further suggest that the hydroid
Obelia griffini Calkins, 1899 is a probable member
of the North Pacific open ocean community. Obelia
griffini was long held to be a synonym of the wide-
spread Obelia dichotoma (Linnaeus, 1758), no doubt
contributing in part to the delay of its recognition as
a distinct member of the oceanic biota.
Biological and Ecological Future of Japanese
Tsunami Marine Debris Biota
The last documentation of living Japanese inver-
tebrates on JTMD coming ashore in the Central or
Eastern North Pacific was between March and May
2017, during a spring pulse, in concert with the
patterns noted by Carlton et al. (2017). For example,
a JTMD bucket (BF-688) with living mussels
(Mytilus galloprovincialis) landed on March 2, 2017
on Long Beach, Washington; in the same early
March period, a JTMD tray (BF-689) with living
Japanese anemones (Anthopleura sp.) landed in
southern Oregon. A JTMD pulse arrived in Hawaii
in April–May 2017, including several objects
landing on Kaua‘i with living Japanese anemones
(JTMD-BF-691, 702, 705–711) and a JTMD buoy
(BF-696) found off the Kona coast on May 11, with
a living M. galloprovincialis. On April 27, a JTMD
buoy (BF-693) landed on Long Beach with living
Japanese limpets. Between June 2017 and December
2017, no further living Japanese species have been
found on JTMD (including buoys, crates, totes, and
vessels) landing in Washington, Oregon, and Hawaii.
Many questions remain about the fate of the
JTMD debris field, the endurance of associated species,
and the potential for colonization by tsunami-
transported species that have arrived in North
America and the Hawaiian Islands. While 2011
tsunami marine debris will continue to come ashore
in North America and the Hawaiian Islands for a
number of years, whether living Japanese species
will continue to arrive in 2018 or beyond, having
survived for more than seven years in what was long
assumed to be a largely in hospitable oceanic environ-
ment, remains unknown. And, as Carlton et al. (2017)
and Carlton and Fowler (2018) discuss, we also await
any detections of establishments of novel species in
the Central and Eastern Pacific that may be linked to
JTMD ocean rafting transport, even as the debris
field steadily fades away.

Ecological and biological studies of ocean rafting
7
Table 2. Examples of contributions to the knowledge of the Japanese and North Pacific Ocean marine fauna and flora from studies of
Japanese tsunami marine debris (JTMD).
New Records for all of Japan or the Tōhoku Coast of Honshu
Taxon Previously known from Comments Reference
Porifera
(sponges)
Haliclona xena de Weerdt,
1986 Eastern North Atlantic Ocean
regarded as introduced to Western
Europe; possible endemic region
unknown until now Elvin et al. 2018
Halisarca “dujardini”
Johnston, 1842 Peter the Great Bay
Hydrozoa
(hydroids)
Plumalecium plumularioides
(Clark, 1877) Kurile Islands and Bering Sea
placed in a new family, Plumaleciidae
Choong and Calder, 2018 in Choong et
al. 2018
Choong et al. 2018
Hydrodendron gracile
(Fraser, 1914) Kurile Islands and Sea of Japan Calder et al. 2014
Polyplacophora
(chitons)
Acanthochitona rubrolineata
(Lischke, 1873) Southern Hokkaido to China a former synonym of A. achates,
revived as a valid species Eernisse et al. 2018
Ostracoda Sclerochilus verecundus
Schornikov, 1981 Shikotan Island to South Korea
may have been mis-identified previously
from the Tōhoku region as Sclerochilus
mukaishimensis Okubo, 1977
Tanaka et al. 2018
Copepoda Harpacticus nicaeensis
Claus, 1866-group
Mediterranean and Ponto-
Caspian Basin may be an undescribed species Cordell 2018
Bryozoa
Biflustra cf. arborescens
(Canu and Bassler, 1928)
Western and Eastern Atlantic
Ocean
McCuller and Carlton
2018
Conopeum nakanosum
Grischenko, Dick and
Mawatari, 2007
South China Sea; introduced to
New Zealand-Australia and
Brazil
may also have been acquired south of
Tōhoku coast
Cribrilina mutabilis Ito,
Onishi and Dick, 2015 Hokkaido
Microporella luellae
Grischenko, Dick and
Mawatari, 2007
Hokkaido
Microporella neocriboides
Dick and Ross, 1988 Hokkaido and Alaska
Watersipora mawatarii
Vieira, Spencer Jones and
Taylor, 2014
Hokkaido may also have been acquired south of
Tōhoku coast
Callopora craticula (Alder,
1856) Hokkaido
Bugulina stolonifera
(Ryland, 1960) Tokyo Bay
northward extension to Tokyo Bay to
2013 (McCuller and Carlton 2018), but
present by 2011 in Misawa (Aomori
Prefecture)
New Records for Central Honshu
Bryozoa Bugula constricta Yanagi
and Okada, 1918 Sagami Bay Elevated to full species status from
Bugula scaphoides constricta McCuller et al. 2018
New Species
Taxon Comments Reference
Polyplacophora
(chitons) Acanthochitona n.sp. Honshu and Ogasawara (Bonin) Islands Eernisse et al. 2018
Ostracoda Sclerochilus n. sp. Tanaka et al. 2018
Bryozoa
Bugula tsunamiensis McCuller et al. 2018
Callaetea n. sp. McCuller and Carlton
2018
Arbocuspis n. sp.
Rhodophyta
(red algae)
Tsunamia transpacifica new genus and new species West et al. 2016
Stylonematophyceae, n. sp. known as a DNA sequence
Rediscovered Species on Tōhoku Coast of Honshu
Taxon History Reference
Bryozoa Escharella hozawai (Okada,
1929) Last collected in 1920s in Mutsu Bay, Aomori Prefecture McCuller and Carlton
2018
Recognition of Novel Member of Oceanic Fauna
Hydrozoa
(hydroids) Obelia griffini Calkins, 1899 Previously considered as a member of the neritic fauna Choong et al. 2018

J.T. Carlton et al.
8
Table 3. Examples of molecular genetic contributions to Japanese tsunami marine debris (JTMD) invertebrate and fish biodiversity
(* detected in JTMD only as a DNA sequence).
Taxon
JTMD sequence match
(98% or better) to GenBank
sequence from:
JTMD sequences
(GenBank deposition
numbers)
Reference
Porifera
(sponges)
*Halisarca “dujardini” White Sea (EU237483) and
North Sea (HQ606143) MG808392 Elvin et al. 2018
*Haliclona xena The Netherlands (JN242209) MG808391 Elvin et al. 2018
Hydrozoa
(hydroid)
*Gonionemus vertens Japan, Russia, New England
(numerous sequences) Choong et al. 2018
Eutima japonica Japan (AB458489) Calder et al. 2014
Bryozoa
*Bugulina stolonifera Galizia, Spain (KC129849-1) McCuller and Carlton
2018
Bugula tsunamiensis,
new species — MF593127 McCuller, Carlton and
Geller 2018
Bivalvia:
Teredinidae
(shipworms)
Bankia bipennata — KY250360
Treneman et al. 2018a, b
Bankia carinata — KY250355
Psiloteredo sp. — KY250324-29; KY250343-49
Teredothyra smithi — KY250357-59
Polyplacophora
(chitons)
Mopalia seta Russia (EU407017,
EU409069)
MG680054-58
MG680083-86
Eernisse et al. 2018
Acanthochitona
achates — MG677923-34
MG679991-6780001
Acanthochitona sp. A — MG79937-53
MG80003-80020
Acanthochitona
rubrolineata — MG679935-36
MG680002
Pisces: Carangidae
(yellowtail jack) Seriola aureovittata Japan (numerous sequences) MF069448–MF069455
MF0609456–MF069462 Craig et al. 2018
Acknowledgements
Facilitating and supporting this Special Issue of Aquatic Invasions
through their guidance and superb editing skills were John Mark
Hanson, Amy Fowler and Vadim Panov. On behalf of the contributors
to this Special Issue, we also thank the many international reviewers
who contributed their expertise and time to the scientific success of
this issue.
As with Carlton et al. (2017), we are indebted to the many scores
of correspondents, collectors, inquisitive beachcombers, and beach
cleanup squadrons who alerted us to potential tsunami debris and
often went the many extra steps to secure samples, if not the objects
themselves. We thank J. Anderson, E. Bakus, R. Barnard, M. Barton,
C. Berg, S. Bertini, C. Braby, D. Breitenstein, C. Burns, A. Burton,
T. Calvanese, T. Campbell, A. Chang, A. Chapman, K. Corbett, D. J.
Courts, B. Cox, F. Custer, R. DiMaria, M. Dumbauld, M. Dundon,
N. Edwards, T. Erben, S. Fradkin, S. Godwin, A. Golay, S. Gorgula,
S. Groth, G. Hansen, C. Havel, S. Holland, L. Humpage, M. Hunter,
A. Hurst, K. Lawrence, M. Lamson Leatherman, B. J. Lee, W. Lilly,
K. Lohan, M. Mekenas, C. Moore, D. Morgan, C. Morishige, K.
Moy, K. Murphy, T. Murphy, B. Neilson, K. Newcomer, N. Osis, R.
Parker, J. Pestana, A. Pleus, C. Plybon, R. Rapalje, M. Reaves, K.
Robison, M. Rogers, S. Rumrill, E. Sanford, S. Santagata, D. Sarver,
C. Schack, J. Schultz, A. Sherwood, J. Sones, S. Steingass, T.
Thompson, M. Volkoff, H. Whalen, M. Wheelock, A. Williams, and
R. Yender for field and laboratory support. We are also grateful to
the many members of the United States Coast Guard who materially
aided in the reporting, tracking, and detection of Japanese tsunami
marine debris.
Without an enduring taskforce of scores of systematists (Carlton
et al. 2017, Supplementary Materials, Table S5) from around the
world, a number of whom have contributed papers to this Special
Issue, we would be unable to speak to the depth and breadth of ocean
rafting biodiversity. Miho Sakuma has, since 2013, provided real-
time translation assistance whether she was in Japan or the United
States. N. Barnea, P. Brady, A. Bychkov, T. Doty, H. Maki, N.
Maximenko, C. C. Murray, T. Therriault, and N. Wallace provided
advice and support. Research support was provided by the Ministry
of the Environment (MOE) of the Government of Japan through the
North Pacific Marine Science Organization (PICES); grants from the
National Science Foundation (Division of Ocean Science, Biological
Oceanography), NSF-OCE-1266417, 1266234, 12667, and 1266406;
Oregon Sea Grant; the Smithsonian Institution, and the Williams
College - Mystic Seaport Maritime Studies Program.
This paper and this Special Issue are dedicated to all those lost,
and all those who lost so much, in the Great East Japan Earthquake
and subsequent tsunami.
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