25 Years of PICES: Celebrating the Past, Imagining the Future November 2-13, 2016

Session 1: Multiple factors affecting the dynamics of shallow-water corals and other organisms < Jeju Island > < Korea map >

Riman

North-Korea

< Jeju University >

Tushima

Yellow-Sea

Kuroshio Contents 01 Introduction & Objectives

02 Material and method

03 Result

04 Summary

05 Discussion 01 Introduction & Objective

 Global warming -> SST(Surface Sea temperature) has been increased – 0.41 for the past 30yrs / 1.29 increase since 1968 in Korea

 Several℃ coral species have migrated℃ towards higher-latitude (Yamano et al. 2011)

 Increased subtropical species in marine ecosystem of Jeju Island

< Seaweed based > < Coral based >

 In this study, annual reproductive cycle and reproductive strategy of two Screlactininan corals, Alveopora japonica and Oulastrea crispata, were analyzed 01 Introduction & Objective Alveopora japonica

kingdom: Animallia phylum: class: order: family: genus: Alveopora

 In shallow rocky foreshores, usually nested among algae and soft corals

 Hemispherical shape, small and less than 40 mm in diameter

 A hermaphroditic brooding coral with oocytes and spermaries developing on separate mesenteries of the polyp (Harii et al., 2001) 01 Introduction & Objective Oulastrea crispata

kingdom: Animallia phylum: Cnidaria class: Anthozoa order: Scleractinia family: Acroporidae genus: Oulastrea

 In murky water and at low tide, colonies size about 10-15cm

 A hermaphroditic coral with oocytes and spermaries developing on same mesenteries of the polyp (Lam, 2000)

 A broadcast spawner and planula brooder (Lam, 2000) 02 Material and method

• Sampling period : January ~ December in 2015

• Location : North (Geumneung) and South (Bomok), 5-10m depth

• Target species : Alveoprora japonica & Oulastrea crispata

• Sampling frequency : Over than 5 colonies for each specie Monthly 02 Material and method

. Standard Histological work for coral research

Sample collection Directly fixation with 10% formalin solution

10% HCl, 20% citric acid with 50% formic Decalcification acid solution

Embedding paraffin blocks Tissue processor machine and then heated paraffin embedding machine

Sectioning & Staining Tissue was Sectioned in 6~7µm and stained followed by H&E staining method

Identifying organisms of corals and sexual Observation gonads, image analysis 02 Material and method

. Image analysis by “Image J”

1 2 3

2 1 3 90°

1. Maximum diameter, (um) 2. Perpendicular diameter, (um) 3. Surface are (um2) 02 Material and method

. Planulae observation

Water tank

Collecting larvae (with 200µm mesh) (200µm mesh) Light

2% glutaraldehyde

50, 70, 90, 95, 100% Ethanol for dehydration

ZEISS Supra 55VP, Korea Basic Science Institute 30, 50, 70, 100% Isoamyl acetate for substitution

Vacuum dry, Water storage coating

03 Result (SST of sampling sites) North : 24.01 30 South : 25.02 ℃

25 ℃

20

15 North South

10

5

0 M A M J J A S O N D

. SST(Surface Sea Temperature) : 13 ~ 25.02℃ 03 Result (A. japonica & O. crispata Oogenesis)

Alveopora japonica Oulastrea crispata

A B E F O O

C D O G O H N

N O O

. (A) Stage 1(Empty stage) in mesoglea(Scale bar=50µm). (B) Stage 2, early development of oocyte(Scale bar=50µm). (C) Stage 3, developing oocyte(Scale bar=100µm). (D) Stage 4, mature oocyte(Scale bar=100µm).

. (E) Stage 1(Empty stage) in mesoglea in January(Scale bar=50µm). (F) Stage 2, early development of oocyte(Scale bar=50µm). (G) Stage 3, late development of oocyte(Scale bar=50µm). (H) Stage 4, Mature oocyte(Scale bar=100µm). N: nucleus, O: oocyte. 03 Result (A. japonica & O. crispata Spermagenesis)

Alveopora japonica Oulastrea crispata

A B E F

mf mf C D G H

S

S

. (A) Stage 1(Empty stage)(Scale bar=100µm) (B) Stage 2, Primordial spermary(Scale bar=50µm) (C) Stage 3, Developing spermary(Scale bar=50µm) (D) Stage 4, Mature spermary(Scale bar=50µm)

. (E) Stage 1 in mesoglea(Scale bar=100µm) (F) Stage 2, Primordial spermary(Scale bar=100µm) (G) Stage 3, Developing speramry(Scale bar=50µm) (H) Stage 4, Mature spermary(Scale bar=200µm) mf: mesenterial filament, S: spermary 03 Result

. Frequency of reproductive stages of A. japonica from North, (A) Oocyte, (B) Spermary

Early Empty Late Ripe Spawning Spawning 100% 100%

90% 90%

80% 80%

70% 70%

60% 60%

50% 50%

40% 40% Frequency(%) 30% 30%

20% 20%

10% 10%

0% 0% Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

2015 2015 03 Result

. Frequency of reproductive stages of A. japonica from South, (A) Oocyte, (B) Spermary

Early Empty Late Ripe Spawning Spawning 100% 100%

90% 90%

80% 80%

70% 70%

60% 60%

50% 50%

40% 40% Frequency(%) 30% 30%

20% 20%

10% 10%

0% 0% Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

2015 2015 03 Result

. Frequency of reproductive stages of O. crispata from South, (A) Oocyte, (B) Spermary

Early Empty Late Ripe Spawning Spawning 100% 100%

90% 90%

80% 80%

70% 70%

60% 60%

50% 50%

40% 40% Frequency(%) 30% 30%

20% 20%

10% 10%

0% 0% Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

2015 2015 03 Result (North, GMD & SA of A. japonica )

200 180 160 140 120 Spawning period 100

GMD(um) 80 60 40 20 0 30000 1 2 3 4 5 6 7 8 9 10 11 12

25000

20000

15000

10000 Surface (um^2)area

5000

0 1 2 3 4 5 6 7 8 9 10 11 12 03 Result (South, GMD & SA of A. japonica )

450

400

350

300

250

200 Spawning period GMD (um) 150

100

50

0 160000 1 2 3 4 5 6 7 8 9 10 11 12

140000

120000

100000

80000

60000 Surface (um^are 2) 40000

20000

0 1 2 3 4 5 6 7 8 9 10 11 12 03 Result (South, GMD & SA of O. crispata )

100 90 80 70 60 50 Spawning period

GMD (um) 40 30 20 10 0 7000 1 2 3 4 5 6 7 8 9 10 11 12

6000

5000

4000

3000

Surface (um^2)are 2000

1000

0 1 2 3 4 5 6 7 8 9 10 11 12 03 Result

. Planulae of A. japonica (South) • From July and Aug A. japonica samples 637 μm

• Size : About 600~700µm for each

• Ability to mobile (Swimming)

• Symbiodiniums which 498.1 μm facilitate photosynthesis were symbiodinium found at endotherm

,, Pictures by digital optical microscope, (Scale bar= 100µm, 200µm), , SEM picture of Planulae,(Scale bar= 20µm, 10µm) 04 Summary

 Slightly difference in maturation period between A. japonica from North and South

Oocytes: March ~ August Spermaries: May ~ July

Oocytes: April ~ August Spemaries: May ~ August, September

 Planulae of A. japonica were collected from July to August (at South site)  The average size - 600µm, possessed motility

Oocytes: May ~ September Spermaries : May ~ October 05 Discussion

 A. japonica and O. crispata are a hermaphroditic brooding coral with oocytes and spermaries developing on separate mesenteries of the polyps

 Seasonal patterns of gametogenesis were shown from those species

 Gonial mitosis occurring in late January

 The major spawning of those two species appeared to followed a period of rising the water temperature in September in Jeju Island

 More research on physiology and ecology of those species are required in various area

 Long-term environmental monitoring is also necessary to prepare for climate changes ありがとうございます。 谢谢您。 Merci. ًﺷﻛﺭﺍ Благодарю вас La ringrazio!