Maturity and Spawning of the Marbled Flounder Pseudopleuronectes yokohamae off the Coast of Pohang, East Sea

367

Copyright © 2016 The Korean Society of Fisheries and Aquatic Science pISSN:0374-8111, eISSN:2287-8815

서 론

문치가자미

(Pseudopleuronectes yokohamae)

^{는 가자미목}

(Pleuronectiformes)

가자미과

(Pleuronectidae)

에속하는어종 으로우리나라전해역

,

^{일본북해도}

,

^{동중국해에분포하는연} 안냉수성저서어류로알려져있다

(Kang et al., 1985; Kim and Youn, 1994; Kim et al., 2005; FishBase, 2015).

^{문치가자미}

의학명은우리나라에서과거

Pleuronectes yokohamae

^로통용 되었으나

,

^{최근의계통분류학적연구결과에따라본연구에서} 는

Pseudopleuronectes yokohamae

^{로표기하였다}

(Ji et al., in

press).

우리나라연안의문치가자미는소규모회유성어종으

로남해안문치가자미의경우연안에서산란을하고근해로이 동하는것으로알려져있고

(Seo et al., 2010),

^{서해안문치가} 자미의경우에는여름에북위

37

^{도이북해역에서만분포하다}

동해 포항 연안 문치가자미(Pseudopleuronectes yokohamae)의 성숙과 산란

김소라ㆍ차형기ㆍ이재봉 ¹ ㆍ이해원 ² ㆍ양재형 ³ ㆍ백혜자 ⁴ ㆍ김성태 ⁵ *

국립수산과학원 연근해자원과, ¹국립수산과학원 원양자원과, ²국립수산과학원 연구협력과, ³동해수산연구소 자원환경과,

4부경대학교 자원생물학과, ⁵동해수산연구소 독도수산연구센터

Maturity and Spawning of the Marbled Flounder Pseudopleuronectes yokohamae off the Coast of Pohang, East Sea

So Ra Kim, Hyung Kee Cha, Jae Bong Lee

¹

, Hae Won Lee

²

, Jae Hyeong Yang

³

, Hea Ja Baek

⁴

and Sung Tae Kim

⁵

*

Coastal Water Fisheries Resources Research Division, National Institute of Fisheries Science, Busan 46083, Korea

1

Distant Water Fisheries Resources Research Division, National Institute of Fisheries Science, Busan 46083, Korea

2

Research Cooperation Division, National Institute of Fisheries Science, Busan 46083, Korea

3

Fisheries Resources and Environment Research Division, National Institute of Fisheries Science, Gangneung 25435, Korea

4

Department of Marine Biology, Graduate School, Pukyong National University, Busan 48513, Korea

5

Dokdo Fisheries Research Center, National Institute of Fisheries Science, Pohang 37709, Korea

Marbled flounder Pseudopleuronectes yokohamae is a commercially important flatfish in the coastal waters of the East Sea off Pohang, Korea. Maturity and spawning dynamics of P. yokohamae were investigated based on samples collected by gill net and long line in the coastal waters off Pohang from January 2013 to December 2014. We ana- lyzed monthly changes in maturity stage, gonadosomatic index (GSI), egg diameter, fecundity, and total length at 50% group maturity. We found that the spawning period was December to February, wherein fecundity ranged from 55,760 eggs at 20.40 cm total length (TL) to 1,559,007 eggs at 46.6 cm TL. The relationship between TL and fecun- dity (F) was F = 0.0017 TL ^3.5604 (R ² = 0.6984), and F increased with increasing TL. We estimated the TL at 50% group maturity as 27.4 cm for female and 23.5 cm for male P. yokohamae , respectively. The results from this research will aid in the development of policies on season and minimum catch length for sustainable production of P. yokohamae . We propose that it is necessary to conduct long-term ecological monitoring for this species because biological proper- ties such as spawning ecology and growth performance are being affected by climate change.

Key words: Maturity, Spawning, Marbled flounder, Pseudopleuronectes yokohamae , East Sea

This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial Licens (http://creativecommons.org/licenses/by-nc/3.0/) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.

http://dx.doi.org/10.5657/KFAS.2016.0367 Korean J Fish Aquat Sci 49(3) 367-375, June 2016

Received 5 February 2016; Revised 13 May 2016; Accepted 13 June 2016

*Corresponding author: Tel: +82. 54. 724. 1020 Fax: +82. 54. 724. 1088

E-mail address: [email protected]

김소라

ㆍ

차형기

ㆍ

이재봉

ㆍ

이해원

ㆍ

양재형

ㆍ

백혜자

ㆍ

김성태

368

가

,

^{겨울철에남쪽으로이동하는것으로알려져있다}

(NFRDI,

2004a).

또한문치가자미는 주로이매패류

(Bivalvia),

단각류

(Amphipoda),

^{갯지렁이류}

(Polychaeta)

^{를섭식하고}

,

^그외산호 충류

(Anthozoa),

거미불가사리류

(Ophiuroidea)

등 다양한저 서동물을섭식하는육식성어류

(carnivore)

^{로알려져있다}

(Huh et al., 2012).

동해안의 문치가자미는경상북도 포항연안에서연안자망과 연안연승에의해대부분어획되고있으며

,

^{가자미류활어위} 판량의약

60%

를차지하여상업적으로매우가치가높은어종

이므로

(NFRDI, 2014),

^{대상자원의지속적인이용을위한자}

원관리방안으로금어기및포획금지체장을설정하여관리하 고있다

.

문치가자미생태에관한이전연구동향을살펴보면

,

^난과자 어의초기발달

(Yusa, 1960; Han et al., 2001),

생식특성및개 체군동태

(Lee et al., 1985; Kang et al., 1985),

^식성

(Huh et al., 2012),

^{연령과성장}

(Suzuki, 1967; Solomon et al., 1987;

Kim et al., 1991; Shafieipour et al., 1999; Kooka et al., 2000;

Kume et al., 2006; Lee et al., 2009; Hoshio et al., 2012; Joo and Gwak., 2014; Kim et al., 2015),

재생산

(Kume et al., 2006;

Tanda et al., 2008; Seo et al., 2010)

^{등다양한연구가진행된바} 있다

.

^{하지만이전연구의대부분이일본연안및우리나라서해} 안과남해안에집중되어있어

,

동해안문치가자미에관한생태 학적연구는전무한실정이다

.

문치가자미와 같은 가자미과

(Family Pleuronectidae)

에 속 하는 물가자미

(Eopsetta grigorjewi)

와 홍가자미

(Hippoglos- soides dubius)

^의경우

,

^{해역별서식처에따라산란시기에차} 이를보인다는연구가보고되었다

(Cha et al., 2011; Choi et al.,

2013).

^{이와같이문치가자미또한해역별서식처에따라산란}

특성의차이가있을것이라생각된다

.

문치가자미의효율적인 자원관리를위해서는각해역별산란시기및성숙체장을바탕 으로금어기및금지체장이설정되어야할것으로생각된다

.

따라서

,

본연구는문치가자미의해역별효율적인관리방안을 마련하기위한기초자료로서동해포항연안에서식하는문치가 자미의성숙도

,

생식소숙도지수

(GSI),

난경

,

포란수및군성숙 도등을매월분석하여동해안서식문치가자미의성숙과산란 특성을밝히고자한다

.

재료 및 방법

본연구에사용된문치가자미는

2013

^년

1

^월부터

2014

^년

12

월까지경북포항연안자망어업과연승어업에서어획된것을 매월구입하여조사하였다

(Fig. 1).

^{분석에사용된시료는실} 험실에서암

·

수별로전장

(TL, Total length) 0.1 cm,

체중

(BW, Body weight) 0.01 g

^{그리고생식소중량}

(GW, Gonad weight) 0.01 g

^{단위까지측정하였다}

.

^{문치가자미의월별암}

·

^수성비차 이는

chi-square test

^{를통해유의성검증을하였다}

(X

²

-test).

^문 치가자미의 생식소발달과정은

NFRDI (2004b)

^{를 참고하여}

생식소의크기및모양

,

^색

,

^{난의투명상태}

,

^{난립의크기등을} 기준으로하였으며

,

생식소발달단계는미숙

(immature),

중숙

(maturing),

^완숙

(mature),

^방중

(spawning),

^방후

(spent) 5

^단계 로구별하여월별성숙도비율을나타내었다

.

월별생식소숙도 지수

(Gonadosomatic Index, GSI)

^{는다음의식을이용하여구} 하였다

.

GSI =

^GW_BW

× 10

²

여기서

GW

는 생식소중량

(g, wet weight), BW

는 체중

(g, wet weight)

^{을각각나타낸다}

.

^{또한본연구에서는한국해양자}

료센터

(KODC)

의포항연안의표층수온 자료를사용하여

,

포

항문치가자미의생식소숙도지수

(GSI)

^{변화와월간수온변화} 의관계를알아보았다

.

산란시기내난경변화를알아보기위하여성숙도와월별로나

누어어체의난소일부를절취하여

, Gilson

^{용액에고정시킨후}

난을분리한뒤

1

개체당

100

개씩을선별하여난경

0.001 mm

까지측정하였다

.

포란수

(F)

^{는산란기로추정되는}

1-2

^{월의성숙개체의난소에} 서일부생식소를절취한뒤실체현미경

(LEICA, MZ-125)

으 로계수하여

,

^{습중량법으로구하였다}

.

F =

^{A - B}_C

× e

여기서

, A

는난소의중량

, B

는난소껍질의중량

, C

는난소일 부의중량

,

^그리고

e

^는

C

^{의난수이다}

.

군성숙도는산란기로 추정되는 시기의중숙 이상의개체를 산란가능군으로 보고 전장계급을

1 cm

단위로 구분하여 성 숙개체의 비율로써 구하였으며

, 50%

^{성숙체장은}

logistic

^식

(Zhang, 2010)

에적용시켜구하였다

.

P

_i

=

_1+e

_(b

¹

× e

1

- b

₂

TL

_i

)

여기서

P

_i^는

i

^{체장계급에서의군성숙비율}

, TL

_i^는

i

^체장계급 의전장

,

^그리고

b

¹

, b

^{2는상수이다}

.

결 과

체장분포 및 암수비율

2013

^년

1

^월부터

2014

^년

12

^{월까지동해포항연안에서자망} 및연승어업으로어획된암

·

^수총

5,024

^{개체의문치가자미를} 측정한결과

(Table 1, Fig. 2),

^총

2,795

^{개체의암컷전장은최} 소

15.0 cm

에서최대

46.6 cm,

평균전장은

27.0 cm

로나타났

으며

, 25.0-25.9 cm

^범위에서

8.2%

^{로가장높은분포를보였다}

.

총

2,229

^{개체의수컷전장은최소}

13.9 cm

^에서최대

40.3 cm,

평균

24.6 cm

^{로나타났으며}

, 23.0-23.9 cm

^범위에서

11.7%

^로 가장높은분포를보였다

.

^{조사기간중채집된암}

·

^{수의성비는}

55.6:44.4

로암컷의비율이수컷보다높았다

(X

²

-test, P<0.05).

체급별성비는

27 cm

^{이하에서수컷이암컷보다높았고}

,

^그이 상의체장에서는암컷의비율이높게나타났다

.

생식소 발달과정

일반적으로 경골어류의 난소는 크게 나상형

(gymnovarian conditon)

과낭상형

(crystovarian conditon)

으로나뉜다

.

문치

가자미의난소는좌우로분리된한쌍의비대칭낭상형

(crys-

tovarian conditon)

^으로

,

^{정소는좌우비대칭의엽상형으로각} 각분리되어있었다

.

^{이는기름가자미}

,

^참가자미

,

^돌가자미

,

^찰 가자미등의가자미류

(Cha et al., 2008; Cha et al., 2006; Jun.,

2003; Byun., 2002)

^{와동일한형태로관찰되었다}

. 암컷

미숙

(Immature)

^{단계의난소는투명한선홍색이며표피가얇}

고육안으로난이거의보이지않았다

(Fig. 3A).

중숙

(Matur-

ing)

^{단계의난소는연한주황색의난이보였지만 그크기는}

아주작았다

(Fig. 3B).

완숙

(Mature)

단계는난의크기가커졌 고

,

^{투명난과진한주황색의난이같이보였다}

(Fig. 3C).

^방중

(Spawning)

^{단계의난소색은어둡고진한주황빛을띠었으며}

,

어체의

1/2

정도가투명난으로가득찼다

.

복부를누르면난이

어체밖으로흘러나왔다

(Fig. 3D).

^방후

(Spent)

^{단계의난소는} 탁한흰색과자색을띠었으며

,

크기가줄고표피가얇아졌다

.

방 란후잔존난을볼수있었다

(Fig. 3E).

수컷

미숙

(Immature)

^{단계의정소는 연한 백색으로 연분홍색의}

Table 1. Monthly size distributions (TL, cm) of marbled flounder Pseudopleuronectes yokohamae in the coast of Pohang, East Sea, January 2013-December 2014

Year Month Female Male

Range (cm) Mean (cm) n Sex ratio (%) Range (cm) Mean (cm) n Sex ratio (%)

2013

Jan. 22.1-43.5 30.4 121 41.0 17.9-35.6 26.2 174 59.0

Feb. 17.8-35.5 25.3 67 48.2 17.6-29.0 24.3 72 51.8

Mar. 17.0-37.7 25.4 70 46.4 15.0-33.0 22.4 81 53.6

Apr. 17.0-35.1 26.4 79 61.7 13.9-30.2 22.9 49 38.3

May 16.3-35.5 25.9 78 53.1 15.4-34.0 23.9 69 46.9

Jun. 15.0-36.5 25.5 91 47.4 17.2-35.5 24.5 101 52.6

Jul. 17.9-36.1 25.2 67 50.0 15.4-31.9 23.7 67 50.0

Aug. 21.7-35.5 28.1 66 54.1 18.5-35.5 26.3 56 45.9

Sep. 17.0-37.5 26.2 108 62.1 17.1-31.5 23.5 66 37.9

Oct. 17.8-36.5 26.0 72 61.0 17.4-30.6 22.2 46 39.0

Nov. 16.0-45.2 27.0 337 61.2 15.5-40.3 24.5 214 38.8

Dec. 15.6-46.6 26.3 367 62.4 15.5-35.5 24.3 221 37.6

2014

Jan. 20.1-36.4 27.6 155 72.4 20.1-33.0 25.0 59 27.6

Feb. 16.8-35.8 25.7 145 60.2 17.5-32.6 23.3 96 39.8

Mar. 15.8-45.5 28.2 153 51.2 18.6-35.5 24.7 146 48.8

Apr. 19.0-45.0 26.8 160 57.8 19.0-37.5 24.8 117 42.2

May 16.4-43.5 27.0 92 55.4 18.3-33.8 24.0 74 44.6

Jun. 18.2-35.0 28.2 67 50.8 18.6-32.8 25.9 65 49.2

Jul. 18.0-43.0 28.4 98 57.0 19.3-33.6 25.6 74 43.0

Aug. 17.5-40.4 27.0 111 56.9 17.3-33.4 25.3 84 43.1

Sep. 19.7-42.1 29.2 47 42.0 20.5-31.9 25.8 65 58.0

Oct. 21.1-36.8 27.3 48 37.2 17.6-31.7 25.7 81 62.8

Nov. 19.2-40.4 26.9 92 48.2 18.5-36.7 26.0 99 51.8

Dec. 16.1-38.1 27.1 104 66.2 17.5-38.7 25.6 53 33.8

Total 15.0-46.6 27.0 2,795 55.6 13.9-40.3 24.6 2,229 44.4

김소라

ㆍ

차형기

ㆍ

이재봉

ㆍ

이해원

ㆍ

양재형

ㆍ

백혜자

ㆍ

김성태

370

혈관이보였다

(Fig. 4A).

^중숙

(Maturing)

^{단계의정소는 유백} 색이며탄력이있다

(Fig. 4B).

^완숙

(Mature)

^{단계의정소는진} 한유백색이고

,

점성이높은유백색으로보였다

(Fig. 4C).

방중

(Spawning)

^{단계의정소는진한백색을보였고}

,

^{어체의복부}

를누르게되면유백색의진액이어체밖으로흘러나왔다

(Fig.

4D).

^방후

(Spent)

^{단계의정소크기는미숙단계의크기였으며}

,

색은연한백색을보였다

(Fig. 4E).

월별 성숙도 비율

본연구에사용된문치가자미암컷의월별성숙도비율을보 면

(Fig. 5A),

^{미숙개체는}

2013

^년

2-12

^월에

36.5-100%, 2014

Fig. 1. Sampling area of the Pseudopleuronectes yokohamae in the

coast of Pohang, East Sea.

15 10 5 0 5 10 15

12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46

Frequency (%)

Total length (cm)

Female N : 2,795 Avg.: 27.0 cm

Male N : 2,229 Avg.: 24.6 cm

Frequency (%)

0 20 40 60 80

100 (A) Female

(B) Male

Immature Maturing Mature Spawning Spent

0 20 40 60 80 100

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

2013 2014

Immature Maturing Mature Spawning Spent

0 5 10 15 20 25 30

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

2013 2014

Water temperature ( ℃ )

F = 0.0025TL

^3.4589

R² = 0.7183

0 200 400 600 800 1000 1200 1400 1600 1800

15 20 25 30 35 40 45 50

Fecundity (×10

3

eg gs)

Total length (cm)

0 25 50 75 100

Female TL

_50%

= 27.4 cm

0 25 50 75 100

0 5 10 15 20 25 30 35 40 45 50

Total Length (cm) Male TL

_50%

= 23.5 cm

Group maturity (%)

0 5 10 15 20 25

30 (A) Female

0 5 10 15 20 25 30

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

2013 2014

(B) Male

Gonadosomatic index

80 60 40 20 0

Immature 14’ OCT, 20.

GSI = 0.52 TL : 23.6 cm

80 60 40 20 0

Maturing 13’ Nov, 15.

GSI = 5.86 TL : 38.6 cm

80 60 40 20 0

Maturing 13’ Dec, 16.

GSI = 13.97 TL : 30.0 cm

60 40 20 0

Mature 14’ Jan, 24.

GSI = 18.73 TL : 28.8 cm

60 40 20 0

Spent 14’ Feb, 21.

GSI = 2.89 TL : 27.0 cm

0 100 200 300 400

Eggs diameter (μm)

Frequency (%)

500 600 700 800

Fig. 2. Length-frequency distribution of marbled flounder Pseudo- pleuronectes yokohamae in the coast of Pohang, East Sea.

Fig. 3. Maturity stages of female marbled flounder Pseudopleu- ronectes yokohamae in the coast of Pohang, East Sea. (A), Im- mature (Sampled in June 2014); (B), Maturing (December 2013);

(C), Mature (February 2014); (D), Spawning (February 2014); (E), Spent (April 2014).

A B

C D

E

Fig. 4. Maturity stages of male marbled flounder Pseudopleuro- nectes yokohamae in the coast of Pohang, East Sea. (A), Immature (Sampled in March 2014); (B), Maturing (December 2014); (C), Mature (December 2013); (D), Spawning (January 2014); (E), Spent (March 2014).

A B

C D

E

동해 포항 연안 문치가자미의 성숙과 산란

371

년

1-12

^월에

31.6-100%

^{로연중출현하였다}

.

^{중숙개체는}

2013

년

10-12

월에

27.6-63.5%, 2014

년

10-12

월에

35.4-53.3%

로 높은비율을 보였다

.

^{완숙개체는}

2013

^년

1

^월에

71.9%

^{로 가} 장높은 비율을나타냈으며

, 2013

^년

12

^월

-

^이듬해

1

^월까지는

22.4-31.0%

^{의비율을보였다}

.

^{방중개체는}

2013

^년

1-2

^월까지

9.0-9.1%

^{의비율을보였으며}

, 2014

^년

1

^월에

2.6%

^{를나타내었} 다

.

방후개체는

2013

년

1-2

월에

18.2-19.4%, 2014

년

1-2

월에

17.9-34.8%

^{의비율을보였다}

.

문치가자미수컷의월별성숙도비율을보면

(Fig. 5B),

^미숙 개체는

2013

^년

2-12

^월에

34.7-100%, 2014

^년

1-12

^월에

37.4- 100%

^{로연중출현하였다}

.

^{중숙개체는}

2013

^년

11-12

^월에

26.0- 54.7%, 2014

년

10-12

월에

6.2-55.6%

의높은비율을보였다

.

완숙개체는

2013

^년

12

^월에

36.8%

^{로높은비율을나타냈으며}

, 2014

^년

11-12

^월에는

3.8-7.1%

^{의비율을보였다}

.

^{방중개체는}

2013

^년

1-2

^월에

33.3-82.8%

^{로높은비율을보였고}

, 2014

^년

1

월에는

52.5%

^{의비율을보였다}

.

^{방후개체는}

2013

^년

1-2

^월에

16.7-31.9%, 2014

년

1-2

월에

3.4-22.9%

의비율을보였다

. 생식소 숙도지수(GSI)의 월 변화

문치가자미암컷의생식소숙도지수

(GSI)

^를보면

(Fig. 6A), 2013

^년

1

^{월에최대값}

18.48

^{을나타낸후급격히감소하여}

3-9

월까지

0.51-2.26

^{의낮은값을보였다}

. 10

^{월부터는점차증가하} 여

12

월에

6.66, 2014

년

1

월에

8.39

로높은값을보이다가

2

월

에급격히감소하였다

.

^이후

10

^월까지

0.58-4.56

^{의낮은값을} 보였고

,

다시

11-12

월에점차증가하였다

.

문치가자미수컷의생식소숙도지수

(GSI)

^를보면

(Fig. 6B), 2013

년

1

월에최대값

9.77

을나타내었고이후급격히감소하 여

3-10

^월까지

0.19-0.52

^{의낮은값을보였다}

. 11

^{월부터는점차} 증가하기시작하여

12

^월

-

^이듬해

1

^월까지

8.92-6.54

^로높은값 을나타냈다

.

이후

10

월까지

0.20-0.93

의낮은값을보이며

, 11

월부터다시증가하여

12

^월에

8.77

^로높은

GSI

^{값을보였다}

.

^이 상의월별생식소숙도지수변화를바탕으로추정된문치가자 미의주산란기는

12-2

^월이다

.

포항연안 수온의 월변화와 생식소 숙도지수의 관계 2013-2014

년포항연안의월별수온변화를보면

(Fig. 7), 2013

년

1

^월에

6.8℃

^{로최저수온을보였고}

,

^{봄과여름철수온이점차} 증가하여

9

월에는

23.8℃

로최고수온을보였다

.

그후수온은 점차감소하여

2014

^년

1

^월에다시

7.4℃

^{의연간최저수온을기} 록하였고

,

^{다시점차증가하여}

9

^월에

23.8℃

^{로최고수온을보} 였다

.

포항연안수온의변화는

1

월에최저수온을보이고점차 증가하여

9

^{월에최고수온이보이는패턴을보였다}

.

포항연안의수온과문치가자미의생식소숙도지수

(GSI)

와의 관계를살펴보면

,

^{암컷은수온이가장낮은}

1

^월

(6.8℃)

^에

GSI

^값 이가장높았고수온이점차높아지는

3-9

^월

(10.2-23.8℃)

^에는 낮게나타나고

,

다시수온이낮아지는

10

월

(19.5℃)

부터

GSI

값이서서히높아졌다

.

^수컷은

11

^월

(15.1℃)

^부터

GSI

^값이높

15 10 5 0 5 10 15

12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46

Frequency (%)

Total length (cm)

Female N : 2,795 Avg.: 27.0 cm

Male N : 2,229 Avg.: 24.6 cm

Frequency (%)

0 20 40 60 80

100 (A) Female

(B) Male

Immature Maturing Mature Spawning Spent

0 20 40 60 80 100

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

2013 2014

Immature Maturing Mature Spawning Spent

0 5 10 15 20 25 30

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

2013 2014

Water temperature ( ℃ )

F = 0.0025TL

^3.4589

R² = 0.7183

0 200 400 600 800 1000 1200 1400 1600 1800

15 20 25 30 35 40 45 50

Fecundity (×10

3

eg gs)

Total length (cm)

0 25 50 75 100

Female TL

_50%

= 27.4 cm

0 25 50 75 100

0 5 10 15 20 25 30 35 40 45 50

Total Length (cm) Male TL

_50%

= 23.5 cm

Group maturity (%)

0 5 10 15 20 25

30 (A) Female

0 5 10 15 20 25 30

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

2013 2014

(B) Male

Gonadosomatic index

80 60 40 20 0

Immature 14’ OCT, 20.

GSI = 0.52 TL : 23.6 cm

80 60 40 20 0

Maturing 13’ Nov, 15.

GSI = 5.86 TL : 38.6 cm

80 60 40 20 0

Maturing 13’ Dec, 16.

GSI = 13.97 TL : 30.0 cm

60 40 20 0

Mature 14’ Jan, 24.

GSI = 18.73 TL : 28.8 cm

60 40 20 0

Spent 14’ Feb, 21.

GSI = 2.89 TL : 27.0 cm

0 100 200 300 400

Eggs diameter (μm)

Frequency (%)

500 600 700 800

Fig. 5. Monthly changes in maturity stages of female (A) and male (B) marbled flounder Pseudopleuronectes yokohamae in the coast of Pohang, East Sea.

15 10 5 0 5

12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46

Frequency (%)

Total length (cm)

Male N : 2,229 Avg.: 24.6 cm

Frequency (%)

0 20 40 60 80

100 (A) Female

(B) Male

Immature Maturing Mature Spawning Spent

0 20 40 60 80 100

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

2013 2014

Immature Maturing Mature Spawning Spent

0 5 10 15 20 25 30

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

2013 2014

Water temperature ( ℃ )

F = 0.0025TL

^3.4589

R² = 0.7183

0 200 400 600 800 1000 1200 1400 1600 1800

15 20 25 30 35 40 45 50

Fecundity (×10

3

eg gs)

Total length (cm)

0 25 50 75 100

Female TL

_50%

= 27.4 cm

0 25 50 75 100

0 5 10 15 20 25 30 35 40 45 50

Total Length (cm) Male TL

_50%

= 23.5 cm

Group maturity (%)

0 5 10 15 20 25

30 (A) Female

0 5 10 15 20 25 30

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

2013 2014

(B) Male

Gonadosomatic index

80 60 40 20 0

Immature 14’ OCT, 20.

GSI = 0.52 TL : 23.6 cm

80 60 40 20 0

Maturing 13’ Nov, 15.

GSI = 5.86 TL : 38.6 cm

80 60 40 20 0

Maturing 13’ Dec, 16.

GSI = 13.97 TL : 30.0 cm

60 40 20 0

Mature 14’ Jan, 24.

GSI = 18.73 TL : 28.8 cm

60 40 20 0

Spent 14’ Feb, 21.

GSI = 2.89 TL : 27.0 cm

0 100 200 300 400

Eggs diameter (μm)

Frequency (%)

500 600 700 800

Fig. 6. Monthly variation in water temperature and gonadosomatic index of the marbled flounder Pseudopleuronectes yokohamae in the coast of Pohang, East Sea (Vertical bars represent the standard deviation).

김소라

ㆍ

차형기

ㆍ

이재봉

ㆍ

이해원

ㆍ

양재형

ㆍ

백혜자

ㆍ

김성태

372

아지기시작하여

12

^월

(9.5℃)

^{에가장높았고}

,

^{수온이높아지는}

3-9

^월에는

GSI

^{값이낮았으며}

,

^{수온이낮아지는}

10

^월부터

GSI

값이서서히높아졌다

.

산란기인

12-2

월간수온은

6.8-9.5℃

범 위를나타내었다

.

난경변화

동해포항연안문치가자미의산란시기난경변화를알아보기 위하여

10-2

^{월의난경변화를관찰하였다}

(Fig. 8). 10

^월

GSI

^값

이

0.52

인개체의난경분포를보면

100 µm

이하의난경이주

모드를이루었고

,

^그후

11

^월에

GSI

^값이

5.86

^{인개체의난경} 이

300-400 µm, 12

월에

GSI

값이

13.97

인개체의난경이

400- 600 µm

^{로주모드를이루었다}

. 1

^월에

GSI

^값이

18.73

^인개체의

600-700 µm

^{의완숙난들이주모드를이루었고}

,

^방란후

2

^월에 는

100 µm

이하의난들이분포하였다

.

포란수

포란기에산란경험이없다고판단되는중숙이상개체

97

미를 대상으로포란수를측정한결과

(Table 2),

^{절대포란수}

(absolute fecundity)

^는최소

55,760

^개

(

^전장

20.4 cm),

^최대

1,559,008

^개

(

전장

46.6 cm)

로계수되었다

.

상대포란수

(relative fecundity)

의경우최소

2,733

^개

(

^전장

20.4 cm),

^최대

35,981

^개

(

^전장

46.6 cm)

로나타났다

.

전장

(TL)

^과포란수

(F)

^{간의관계식은}

F =0.0025TL

^3.4589

(R

²

= 0.7183)

^{이며전장이커질수록포란수가증가하는경향을나}

타내었다

(Fig. 9).

군성숙도

문치가자미의군성숙체장을알아보기위해산란기로추정되 는

12-2

^{월의중숙이상암컷}

473

^미

(

^전장

20.4-46.6 cm),

^수컷

397

^미

(

^전장

17.9-38.7 cm)

^{를대상으로중숙이상개체들이산} Table 2. Absolute and relative fecundities according to total length of marbled flounder Pseudopleuronectes yokohamae in the coast of Po- hang, East Sea, January 2013-December 2014

Total length (cm) Absolute fecundity (eggs) Relative fecundity (eggs/cm)

No. of specimens

Mean Range Mean Range

20.4-24.9 139,444 55,760-221,334 5,991 2,733-9,146 12

25.0-29.9 261,126 82,345-534,918 9,406 3,107-20,110 31

30.0-34.9 429,193 155,629-753,640 13,343 4,646-22,036 34

35.0-39.9 604,945 236,728-946,502 16,244 6,539-23,962 16

40.0-46.6 1,469,096 1,409,897-1,559,008 34,383 33,455-35,981 4

15 10 5 0 5 10 15

12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46

Frequency (%)

Total length (cm)

Female N : 2,795 Avg.: 27.0 cm

Male N : 2,229 Avg.: 24.6 cm

Frequency (%)

0 20 40 60 80

100 (A) Female

(B) Male

Immature Maturing Mature Spawning Spent

0 20 40 60 80 100

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

2013 2014

Immature Maturing Mature Spawning Spent

0 5 10 15 20 25 30

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

2013 2014

Water temperature ( ℃ )

F = 0.0025TL

^3.4589

R² = 0.7183

0 200 400 600 800 1000 1200 1400 1600 1800

15 20 25 30 35 40 45 50

Fecundity (×10

3

eg gs)

Total length (cm)

0 25 50 75 100

Female TL

_50%

= 27.4 cm

0 25 50 75 100

0 5 10 15 20 25 30 35 40 45 50

Total Length (cm) Male TL

_50%

= 23.5 cm

Group maturity (%)

0 5 10 15 20 25

30 (A) Female

0 5 10 15 20 25 30

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

2013 2014

(B) Male

Gonadosomatic index

80 60 40 20 0

Immature 14’ OCT, 20.

GSI = 0.52 TL : 23.6 cm

80 60 40 20 0

Maturing 13’ Nov, 15.

GSI = 5.86 TL : 38.6 cm

80 60 40 20 0

Maturing 13’ Dec, 16.

GSI = 13.97 TL : 30.0 cm

60 40 20 0

Mature 14’ Jan, 24.

GSI = 18.73 TL : 28.8 cm

60 40 20 0

Spent 14’ Feb, 21.

GSI = 2.89 TL : 27.0 cm

0 100 200 300 400

Eggs diameter (μm)

Frequency (%)

500 600 700 800

Fig. 7. Monthly mean sea surface temperatures in the coast of Po- hang, East Sea, January 2013 ~ December 2014.

15 10 5 0 5 10 15

12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46

Frequency (%)

Total length (cm)

Female N : 2,795 Avg.: 27.0 cm

Male N : 2,229 Avg.: 24.6 cm

Frequency (%)

0 20 40 60 80

100 (A) Female

(B) Male

Immature Maturing Mature Spawning Spent

0 20 40 60 80 100

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

2013 2014

Immature Maturing Mature Spawning Spent

0 5 10 15 20 25 30

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

2013 2014

Water temperature ( ℃ )

F = 0.0025TL

^3.4589

R² = 0.7183

0 200 400 600 800 1000 1200 1400 1600 1800

15 20 25 30 35 40 45 50

Fecundity (×10

3

eg gs)

Total length (cm)

0 25 50 75 100

Female TL

_50%

= 27.4 cm

0 25 50 75 100

0 5 10 15 20 25 30 35 40 45 50

Total Length (cm) Male TL

_50%

= 23.5 cm

Group maturity (%)

0 5 10 15 20 25

30 (A) Female

0 5 10 15 20 25 30

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

2013 2014

(B) Male

Gonadosomatic index

80 60 40 20 0

Immature 14’ OCT, 20.

GSI = 0.52 TL : 23.6 cm

80 60 40 20 0

Maturing 13’ Nov, 15.

GSI = 5.86 TL : 38.6 cm

80 60 40 20 0

Maturing 13’ Dec, 16.

GSI = 13.97 TL : 30.0 cm

60 40 20 0

Mature 14’ Jan, 24.

GSI = 18.73 TL : 28.8 cm

60 40 20 0

Spent 14’ Feb, 21.

GSI = 2.89 TL : 27.0 cm

0 100 200 300 400

Eggs diameter (μm)

Frequency (%)

500 600 700 800

Fig. 8. Frequency distributions in egg diameter of marbled floun- der Pseudopleuronectes yokohamae in the coast of Pohang, East Sea.