science.sciencemag.org/content/366/6465/620/suppl/DC1

Supplementary Materials for

Neonicotinoids disrupt aquatic food webs and decrease fishery yields

Masumi Yamamuro*, Takashi Komuro, Hiroshi Kamiya, Toshikuni Kato, Hitomi Hasegawa, Yutaka Kameda

*Corresponding author. Email: limnologyandoceanography@yahoo.co.jp

Published 1 November 2019, Science 366, 620 (2019)

DOI: 10.1126/science.aax3442

This PDF file includes:

Materials and Methods Figs. S1 to S11 Tables S1 and S2 References

1

Materials and Methods

Methods

Lake Shinji (area 79.2 km2, mean depth 4.5 m) is a eutrophic oligohaline lagoon

with a surface water salinity of between 2 and 6 psu. The water layer above the

halocline (ca. 4 m) is well mixed by wind action. The Hii River (Fig. S1) supplies 70%

of the freshwater inflow to Lake Shinji. The watershed of this river covers an area of

approximately 910 km2. Mountain forests cover 89% of this watershed, while rice

paddy and other crop fields cover 9%, and urban areas cover 2% (Izumo River Office:

http://www.cgr.mlit.go.jp/izumokasen/jimusho/suikei-seibi/files/keikaku_02.pdf).

Nutrient concentrations in the effluent from rice paddies determine the nutrient

concentrations of the Hii River (20). Copepods represent more than 95% of the

zooplankton community, while Sinocalanus tenellus represents 96.9% of copepods,

throughout the year (21).

Long-term water quality assessment. We analyzed monitoring data that was

collected monthly for particulate chemical oxygen demand and chlorinity in the surface

water, and for dissolved oxygen in bottom water layer at the center of Lake Shinji.

Surveys were conducted by the Shimane Prefectural Institute of Public Health and

Environmental Science. The same analytical method for chemical oxygen demand

(Japanese Industrial Standard K 0102 17, 100 °C potassium permanganate method) has

been used since April 1984. Particulate chemical oxygen demand was calculated by

subtracting the chemical oxygen demand of Whatman GF/C filtered water from total

chemical oxygen demand. Chlorinity was determined by the Mohr’s method. Dissolved

oxygen concentration was determined by the Winkler’s method.

Long-term zooplankton assessment. Izumo River Office started monitoring

zooplankton abundance at the center of Lake Shinji each month from January 1981. We

obtained zooplankton monitoring data between 1981 and 2017 from the Izumo River

Office, including their permission to use the data. Because neonicotinoid pesticides are

spread in early May when rice is planted, we examined data starting from May 1981

until April 2005. Some data were missing due to poor sampling conditions (December

1981, March 1982, March, April, May 1985, March 1986, March 1987, March 1996). A

plankton net (mesh size 100 m) was towed vertically from 3 m depth to the surface,

and the filtered water was fixed with 5% formaldehyde solution. The volume of filtered

water was calculated by multiplying the area of the net by the towed distance.

Identification and counts of zooplankton individuals were performed in 1 mL

subsamples placed on a glass slide that was observed under a microscope. This process

was repeated until the total zooplankton count exceeded 300. The standing crop was

2

converted to biomass by measuring the body length of each individual of the various

zooplankton species in microphotographs, and using carbon-body length conversion

factors (22).

Long-term fisheries yield assessments. The annual fisheries yield of nine

categories (Hypomesus nipponensis, Plecoglossus altivelis, Salangichthys microdon,

Cyprinus carpio, Carassius spp., Tribolodon hakonensis, Anguilla japonica, Gobioidei

spp., Mugil cephalus, Lateolabrax japonicus and other fishes) since 1952 are available

at the website of the Lake Shinji Fisheries Cooperative Association

(http://shinjiko.jp/relays/download/?file=/files/libs/96/20150604091741688.xls).

Among those, H. nipponensis, P. altivelis, S. microdon, and A. japonica are very

expensive at market, with consistently high fishery effort being guaranteed. However, P.

altivelis mostly lives in freshwater rivers, with less than 10 tons being caught when they

inhabit Lake Shinji during the seaward migration. No individuals have been caught

since 1982. Thus, we examined the relationship between environmental changes at Lake

Shinji and the annual fisheries yield of smelt (H. nipponensis), ice fish (S. microdon),

and eel (A. japonica).

To detect changes to fishing effort, we compiled data on the amount of released

juvenile eel and eyed eggs of smelt every year from 1981 to 2014 from the business

report of Lake Shinji Fisheries Cooperative Association (23).

Macrobenthos assessment. Macrobenthos were surveyed at 248 locations on July

18–30 and August 11–12, 1982 at Lake Shinji (24). To compare the macrobenthos

communities in Lake Shinji between 1982 and the present, we sampled 12 locations on

the west coast, which are closer to the mouth of the Hii River, and 27 locations on the

east coast. Sediment samples (0.1 m2) were collected from an anchored boat using a

Smith-McIntyre grab on August 4–5, 2016. The collected sediments were then washed

through a 0.5-mm sieve. Macrobenthos was preserved with 10% formalin, and the

identification and counting of taxa were performed under a binocular microscope.

Long-term monitoring of Chironomus. plumosus. As eutrophication progressed

in 1970’s, midges of Chironomus plumosus emerging from the lake had reached

intolerable densities. To understand the condition of C. plumosus population, Izumo

River Office started monitoring of the midges of C. plumosus at several points in Lake

Shinji from 1989 to 1992. Sampling points and sampling times were different each

years. Since 1993, Izumo River Office started monitoring of macrobenthos including

the midges of C. plumosus mostly every month at the center of the lake (point 3 in Fig.

S3 (C)), and mostly 4 times per year at three points (1, 7, and 8 in Fig. S3 (C)). We

obtained these monitoring data of C. plumosus from the Izumo River Office, including

3

their permission to use the data. Surface sediments were collected with Ekman grab

(1/25m2) four times at one point. Sediments of ca 0.16 m2 per one point were sieved

with 0.5 mm mesh sieve, and the residue was fixed with neutralized formalin.

Macrobenthos was picked up from the fixed residue under binocular microscope.

Identified macrobenthos was counted and weighed by each species or genera. Number

of C. plumosus was converted to the density per m2.

Neonicotinoid concentrations in the water of Lake Shinji. Water from Lake

Shinji was sampled from three locations once a month from April to June 2018 (Fig.

S1). Rice is primarily planted in the watershed from April 29 through May 5, both of

which are public holidays. Station S7 (ca. 4.5 m deep) is a public monitoring station

where sampling occurs at least three days after a rainfall event to avoid turbid lake

water caused by sediment input from swollen rivers. At Station S7, surface water

samples (2 L) were collected April 10, May 8, and June 4 in 2018 from a boat using a

stainless-steel bucket attached to a string. Stations ST and SA were located at the center

of the south and north shores, with being located ST near the mouth of a small stream

and being SA located within a small port used by local fishermen. At ST, water was

sampled with a stainless-steel bucket at about 80 cm depth by a person wearing waders.

At SA, water was sampled from a jetty, at ca. 1 m depth, with a stainless-steel bucket

attached to a string. Sampling dates at ST and SA were April 23, May 10, and June 12

in 2018. In April and May, no rain had fallen on the two days previous to sampling;

however, it rained for the entire day on June 10 and 11. Water samples from all stations

were immediately transferred to plastic bottles on collection, and were transported to the

laboratory in an ice-box.

We analyzed seven neonicotinoids (acetamiprid, clothianidin, dinotefuran,

imidacloprid, nitenpyram, thiacloprid, and thiamethoxam) that are mainly used on

agricultural lands in Japan. Deutilized certified standards were purchased from Hayashi

Pure Chemicals Industries, Ltd. The pesticide standards mixture was obtained from

Fujifilm Wako Pure Chemical Corporation. All pesticide standards were >99%

compound purity and the deutilized standards were >97% isotopic purity.

Water samples were filtered through glass fiber filters. Then, 10 ng of the

deutilized internal standards were added to 250 mL of each filtrate. The samples were

passed through Inertsep Pharma® solid phase, which was cleaned up by methanol and

ultrapure water. The neonicotinoids and the internal standards were extracted from the

solid phase by 5 mL methanol. The extract was concentrated to dryness. Then, 500 µL

of 15% methanol was added before liquid chromatography tandem mass spectrometry

analysis on a Waters Acquity H-Class HPLC system coupled to a Waters Xevo TQD

4

triple quadrupole mass spectrometer. Neonicotinoids were separated by an Acquity

BEH phenyl column (1.7 μm, 2.1 mm × 75 mm, Waters) at 40 °C. Mobile phase

solvents were 1 mM ammonium acetate solution (A) and methanol (B). The initial ratio

(A:B) was 85:15. Separation was performed using a flow rate of 0.4 mL min-1 with a

gradient shifting from 85:15 to 5:95 in 9.5 min, held for 1 min, and then returned to the

initial conditions, and kept at equilibration for 2 min. The mass spectrometer was

operated in multiple reaction monitoring (MRM) and the electrospray ionization mode

selected was the reaction monitoring. The concentrations of neonicotinoids were

calculated by using precursor ions and fragment ions. Quantification limits of

neonicotinoids were 0.1 ng mL-1 for acetamiprid, thiacloprid, and thiamethoxam, 0.2 ng

mL-1 for nitenpyram, 0.3 ng mL-1 for clothianidin and imidacloprid, and 0.5 ng mL-1 for

dinotefuran.

Statistical analyses. Paired and un-paired t-tests were performed in StatView

(SAS Institute Inc., Mac2Win 1990-94 series). Two-sided testing was used with =

0.05.

5

SACenter

STS7

Ohashi River

N

Fig. S1. Study area including the locations of long term water quality and zooplankton

monitoring station (Center) and water sampling stations for neonicotinoid determination

(S7, SA and ST) in Lake Shinji, Japan. Freshwater inflows to the lake are mainly from

the Hii River watershed that includes large areas of rice paddies. The Ohashi River

functions as both an inlet and an outlet depending on sea level. Polyhaline water (18–30

PSU salinity) from Lake Nakaumi flows into Lake Shinji through the Ohashi River

when sea level rises. Urban areas are located to the north and south of the Ohashi River.

6

Fig. S2.

Abundance of the midge, Chironomus plumosus, at 39 sampling locations in Lake

Shinji, Japan, in the summers of 1982 (left) and 2016 (right). The west end of Lake

Shinji receives freshwater inflow from the Hii River, which drains rice paddies that

have been continuously treated with neonicotinoids since 1993. The east end of Lake

Shinji receives polyhaline water from an adjacent coastal lake via the Ohashi River.

1982

4m

2016

4m

0 1.5 3 4.5 6km 0

1 - 100

101 - 500

501 - 1000

1001 - 1500

(/m2)

7

Fig. S3.

Sampling points of the midges of Chironomus plumosus in August 1991 (A), August 1992

(B) and the survey since August 1993 (C). Number of the midges of C. plumosus per m2

collected in August 1991, 1992 and 1993 is shown in parentheses. Sampling occurred

mostly every month at the center of the lake (point 3 in Fig. S3 (C)), and mostly 4 times

per year at three points (1, 7, and 8 in Fig. S3 (C)) after 1993. Data supplied by the Izumo

River Office. See Table S1 (B) for details about numbers of C. plumosus since August

1993.

8

Fig. S4.

Abundance of the mesohaline isopod, Cyathura muromiensis, in Lake Shinji during the

summers of 1982 (left) and 2016 (right). See Fig. S2 for additional details.

1982 2016

0 1.5 3 4.5 6km 0

1 - 100

101 - 200

201 - 300

301 - 400

(/m2)

3m 3m

9

Fig. S5.

Abundance of the oligohaline polychaete Notomastus sp. in Lake Shinji during the

summers of 1982 (left) and 2016 (right). See Fig. S2 for additional details.

1982 2016

0 1.5 3 4.5 6km 0

1 - 200

201 - 400

401 - 800

801 - 1100

(/m2)

5m 5m

10

Fig. S6.

Distribution of Oligochaeta gen spp. in Lake Shinji during the summers of 1982 (left)

and 2016 (right). See Fig. S2 for additional details.

1982 2016

0 1.5 3 4.5 6km 0

1 - 200

201 - 500

501 - 1000

1001 -1500

(/m2)

5m 5m

11

Fig. S7.

Distribution of the mesohaline polychaete, Laonome albicingillum, in Lake Shinji

during the summers of 1982 (left) and 2016 (right). See Fig. S2 for additional details.

1982 2016

0 1.5 3 4.5 6km 0

1 - 20

21 - 40

41 - 60

61 - 80

(/m2)

5m 5m

12

Fig. S8.

Distribution of the mesohaline polychaete, Prionospio japonica, in Lake Shinji during

the summers of 1982 (left) and 2016 (right). See Fig. S2 for additional details.

1982 2016

0 1.5 3 4.5 6km 0

1 - 150

151 - 300

301 - 450

451 - 650

(/m2)

4m 4m

13

Fig. S9. Particulate chemical oxygen demand (mg L-1) and chlorinity in the surface

water and dissolved oxygen of the bottom water at the center of Lake Shinji sampled

every month from May 1984 to April 2005.

14

Fig. S10. Concentration of four kinds of neonicotinoids in the surface water of Lake

Shinji sampled at three stations (see Fig. S1) in April, May, and June 2018.

0

0.01

0.02

0.03

0.04

0.05

0.06

0.07

0.08

S7 ST SA S7 ST SA S7 ST SA

Thiamethoxam

Imidacloprid

Clothianidin

Acetamiprid

April May June

Co

ncen

tra

tio

n o

f n

eo

nic

otin

oid

(µ

g/L

)

15

Fig. S11. Amount of released juvenile eel and number of eyed eggs of smelt every year

in Lake Shinji from 1981 to 2014. The vertical dashed line indicates when

neonicotinoid use began in the watershed of the lake.

Start of using

neonicotinoids

Weig

ht

of

rele

ased

ju

ven

ile e

el (k

g)

Nu

mbe

r of

rele

ase

d s

me

lt’s

eg

g (

x1

04)

0

100

200

300

400

500

600

700

800

9001

981

1983

1985

1987

1989

1991

1993

1995

1997

1999

2001

2003

2005

2007

2009

2011

2013

Year

0

10000

20000

30000

40000

50000

60000

Juvenil eel

Smelt's egg

16

Table S1. (A)

Number of the midges of Chironomus plumosus per m2 collected in August at the points

shown in Fig. S3. “NC” denotes no collection was performed. Data supplied by the

Izumo River Office.

1 2 3 4 5 6 7 8

Aug-91 0 67 250 67 167 NC NC NC

Aug-92 325 375 0 0 0 0 NC NC

Aug-93 0 NC 0 NC NC NC 0 0

Sampling pointDate

17

Table S1. (B)

Number of the midges of Chironomus plumosus per m2 collected at 4 points shown in

Fig. S3 (C). Sampling occurred mostly every month at the center of the lake (point 3 in

Fig. S3 (C)), and mostly 4 times per year at three points (1, 7, and 8 in Fig. S3 (C)) after

1993. Data supplied by the Izumo River Office.

18

1 3 7 8 1 3 7 8 1 3 7 8

Aug-93 0 0 0 0 Sep-98 1217 0 233 267 Nov-03 0 0 0 0

Sep-93 NC 0 NC NC Oct-98 NC 250 NC NC Dec-03 NC 0 NC 0

Oct-93 NC 0 NC NC Nov-98 NC 692 NC NC Jan-04 NC 0 NC 0

Nov-93 0 0 0 0 Dec-98 NC 558 NC NC Feb-04 0 0 0 0

Dec-93 NC 0 NC NC Jan-99 NC 92 NC NC Mar-04 NC 0 NC 0

Jan-94 NC 0 NC NC Feb-99 175 50 583 533 May-04 0 0 0 0

Feb-94 0 0 0 0 Mar-99 NC 8 NC NC Jun-04 0 0 0 0

Mar-94 NC 0 NC NC Apr-99 NC 0 NC NC Aug-04 0 0 6 0

May-94 0 0 0 0 May-99 1167 0 150 25 Nov-04 0 0 0 0

Jun-94 NC 0 NC NC Jun-99 NC 0 NC NC Feb-05 0 0 0 0

Jul-94 0 0 0 0 Jul-99 750 0 25 0 May-05 6 0 0 0

Aug-94 NC 0 NC NC Aug-99 NC 0 NC NC Jun-05 NC 0 NC NC

Sep-94 0 0 0 0 Sep-99 25 0 42 0 Jul-05 NC 0 NC NC

Oct-94 NC 0 NC NC Oct-99 NC 8 NC NC Aug-05 0 0 0 0

Nov-94 NC 0 NC NC Nov-99 NC 0 NC NC Sep-05 NC 0 NC NC

Dec-94 NC 0 NC NC Dec-99 NC 0 NC NC Oct-05 NC 0 NC NC

Jan-95 NC 0 NC NC Jan-00 NC 0 NC NC Nov-05 0 0 0 0

Feb-95 0 0 0 0 Feb-00 0 0 200 0 Dec-05 NC 0 NC NC

Mar-95 NC 0 NC NC Mar-00 NC 0 NC NC Jan-06 NC 0 NC NC

Apr-95 NC 0 NC NC Apr-00 NC 0 NC NC Feb-06 0 0 0 0

May-95 0 0 0 0 May-00 0 0 0 0 Mar-06 NC 0 NC NC

Jun-95 NC 0 NC NC Jun-00 NC 0 NC NC Apr-06 NC 0 NC NC

Jul-95 0 0 0 0 Jul-00 0 0 0 0 May-06 0 0 0 0

Aug-95 NC 0 NC NC Aug-00 NC 0 NC NC Jun-06 NC 0 NC NC

Sep-95 0 0 0 0 Sep-00 0 0 0 0 Jul-06 NC 0 NC NC

Oct-95 NC 0 NC NC Oct-00 NC 0 NC NC Aug-06 0 0 0 0

Nov-95 NC 0 NC NC Nov-00 NC 0 NC NC Sep-06 NC 0 NC NC

Dec-95 NC 0 NC NC Dec-00 NC 0 NC NC Oct-06 NC 0 NC NC

Jan-96 NC 0 NC NC Jan-01 NC 0 NC NC Nov-06 0 0 0 0

Feb-96 0 0 0 0 Feb-01 0 0 0 0 Dec-06 NC 0 NC NC

Mar-96 NC 0 NC NC Mar-01 NC 0 NC NC Jan-07 NC 0 NC NC

Apr-96 NC 0 NC NC Apr-01 NC 0 NC NC Feb-07 0 0 0 0

May-96 0 0 0 0 May-01 0 0 0 0 Mar-07 NC 0 NC NC

Jun-96 NC 0 NC NC Jun-01 NC 0 NC NC Apr-07 NC 0 NC NC

Jul-96 0 0 0 0 Jul-01 0 0 0 0 May-07 0 0 0 0

Aug-96 NC 0 NC NC Aug-01 NC 0 NC NC Jun-07 NC 0 NC NC

Sep-96 0 0 0 0 Sep-01 0 0 0 0 Jul-07 NC 0 NC NC

Oct-96 NC 0 NC NC Oct-01 NC 0 NC NC Aug-07 0 0 0 0

Nov-96 NC 0 NC NC Nov-01 NC 0 NC NC Sep-07 NC 0 NC NC

Dec-96 NC 0 NC NC Dec-01 NC 0 NC NC Oct-07 NC 0 NC NC

Jan-97 NC 0 NC NC Jan-02 NC 0 NC NC Nov-07 0 0 0 0

Feb-97 0 0 0 0 Feb-02 0 0 0 0 Dec-07 NC 0 NC NC

Mar-97 NC 0 NC NC Mar-02 NC 0 NC NC Jan-08 NC 0 NC NC

Apr-97 NC 0 NC NC May-02 0 0 0 0 Feb-08 0 0 0 0

May-97 0 0 0 0 Jun-02 NC 0 NC NC Mar-08 NC 0 NC NC

Jun-97 NC 0 NC NC Jul-02 NC 0 NC NC Apr-08 NC 0 NC NC

Jul-97 0 0 0 0 Aug-02 0 0 0 0 May-08 0 0 0 0

Aug-97 NC 0 NC NC Sep-02 NC 0 NC NC Jun-08 NC 0 NC NC

Sep-97 0 0 0 0 Oct-02 NC 0 NC NC Jul-08 NC 0 NC NC

Oct-97 NC 0 NC NC Nov-02 0 0 0 0 Aug-08 0 0 0 0

Nov-97 NC 0 NC NC Dec-02 NC 0 NC 0 Sep-08 NC 0 NC NC

Dec-97 NC 0 NC NC Jan-03 NC 0 NC 0 Oct-08 NC 0 NC NC

Jan-98 NC 0 NC NC Feb-03 0 0 0 0 Nov-08 0 0 0 0

Feb-98 0 0 0 0 Mar-03 NC 0 NC 0 Dec-08 NC 0 NC NC

Mar-98 NC 0 NC NC May-03 0 0 0 0 Jan-09 NC 0 NC NC

Apr-98 NC 0 NC NC Jun-03 0 0 0 0 Feb-09 0 0 0 0

May-98 0 0 0 8 Jul-03 NC 0 NC 0 Mar-09 NC 0 NC NC

Jun-98 NC 42 NC NC Aug-03 0 0 0 0 Apr-09 NC 0 NC NC

Jul-98 1108 17 1842 8 Sep-03 NC 0 NC 0 May-09 0 0 0 0

Aug-98 NC 0 NC NC Oct-03 NC 0 NC 0 Jun-09 NC 0 NC NC

Sampling pointDate Date

Sampling point Sampling pointDate

19

Table S1. (B) Continued

1 3 7 8 1 3 7 8

Jul-09 NC 0 NC NC Jun-13 NC 0 NC NC

Aug-09 0 0 0 0 Jul-13 NC 0 NC NC

Sep-09 NC 0 NC NC Aug-13 0 0 0 0

Oct-09 NC 0 NC NC Sep-13 NC 0 NC NC

Nov-09 0 0 0 0 Oct-13 NC 0 NC NC

Dec-09 NC 0 NC NC Nov-13 0 0 0 0

Jan-10 NC 0 NC NC Dec-13 NC 0 NC NC

Feb-10 0 0 0 0 Jan-14 NC 0 NC NC

Mar-10 NC 0 NC NC Feb-14 0 0 0 0

Apr-10 NC 0 NC NC Mar-14 NC 0 NC NC

May-10 0 0 0 0 Apr-14 NC 0 NC NC

Jun-10 NC 0 NC NC May-14 0 0 0 0

Jul-10 NC 0 NC NC Jun-14 NC 0 NC NC

Aug-10 0 0 0 0 Jul-14 NC 0 NC NC

Sep-10 NC 0 NC NC Aug-14 0 0 0 0

Oct-10 NC 0 NC NC Sep-14 NC 0 NC NC

Nov-10 0 0 0 0 Oct-14 NC 0 NC NC

Dec-10 NC 0 NC NC Nov-14 0 0 0 0

Jan-11 NC 0 NC NC Dec-14 NC 0 NC NC

Feb-11 0 0 0 0 Jan-15 NC 0 NC NC

Mar-11 NC 0 NC NC Feb-15 0 0 0 0

Apr-11 NC 0 NC NC Mar-15 NC 0 NC NC

May-11 0 0 0 0 Apr-15 NC 0 NC NC

Jun-11 NC 0 NC NC May-15 0 0 0 0

Jul-11 NC 0 NC NC Jun-15 NC 0 NC NC

Aug-11 0 0 0 0 Jul-15 NC 0 NC NC

Sep-11 NC 0 NC NC Aug-15 0 0 0 0

Oct-11 NC 0 NC NC Sep-15 NC 0 NC NC

Nov-11 0 0 0 0 Oct-15 NC 0 NC NC

Dec-11 NC 0 NC NC Nov-15 0 0 0 0

Jan-12 NC 0 NC NC Dec-15 NC 0 NC NC

Feb-12 0 0 0 0 Jan-16 NC 0 NC NC

Mar-12 NC 0 NC NC Feb-16 0 0 0 0

Apr-12 NC 0 NC NC Mar-16 NC 0 NC NC

May-12 0 0 0 0 Apr-16 NC 0 NC NC

Jun-12 NC 0 NC NC May-16 0 0 0 0

Jul-12 NC 0 NC NC Jun-16 NC 0 NC NC

Aug-12 0 0 0 0 Jul-16 NC 0 NC NC

Sep-12 NC 0 NC NC Aug-16 0 0 0 0

Oct-12 NC 0 NC NC Sep-16 NC 0 NC NC

Nov-12 0 0 0 0 Oct-16 NC 0 NC NC

Dec-12 NC 0 NC NC Nov-16 0 0 0 0

Jan-13 NC 0 NC NC Dec-16 NC 0 NC NC

Feb-13 0 0 0 0 Jan-17 NC 0 NC NC

Mar-13 NC 0 NC NC Feb-17 0 0 0 0

Apr-13 NC 0 NC NC Mar-17 NC 0 NC NC

May-13 0 0 0 0

Sampling point Sampling pointDate Date

20

Table S2.

List of all zoobenthos collected from 39 sampling locations during August 2016.

Species Number of locations

Mollusca Iravadia elegantula 33

Corbicula japonica 30

Assiminea lutea japonica 7

Trapezium liratum 1

Annelida

Prionospio japonica 38

Laonome albicingillum 35

Hediste sp. 14

Polydora sp. 7

Notomastus sp. 7

Carazziella sp. 5

Sigambra phuketensis 3

Capitella capitata 2

Cistenides okudai 2

Eteone longa 1

Heteromastus sp. 1

Oligochaeta gen. spp. 12

Arthropoda

Tanypodinae spp. 33

Neomysis sp. 10

Leucon simanensis 9

Melita spp. 7

Apocorophium acutum 4

Cyathura muromiensis 2

Ampithoe valida 1

Kamaka sp. 1

Gnorimosphaeroma

naktongense

1

Chironomus sp. 1

Ampithoe valida 1

Others

Nemertea gen. spp. 24

Platyhelminth gen. sp. 23

21

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