Stock Assessment Methodologies of reef systems: A Case study

Using Yangmeikeng Artificial Reef

Chuanxin Qin Ph. D South China Sea Fisheries Research Institute, CAFSGerard DiNardo Ph.D Pacific Islands Fisheries Science center, NOAAPimao Chen Prof. South China Sea Fisheries Research Institute, CAFS

Hui-Hua Lee Ph.D Pacific Islands Fisheries Science center, NOAA

Contents

2 Results

3 Conclusion

4 Next step plan

Exchange contents1

Exchange contents

1

What did we do in Hawaii？

Contents: what did we do in Hawaii…

The content, method, data require, and data processing software of artificial reef fisheries resource stock assessment.

Introduced to R software for use in stock assessment The fishery resources and resource management status in

Hawaii and South China Sea were discussed. China’s Summer Fishing Moratorium (close season), stocking enhancement, artificial reef construction, MPA and other management strategies for fishery resources recession in China were discussed too.

Some similarities between artificial reef stock assessment and coral reef stock assessments. Thus, the statistics methods used in coral reef stock assessment can apply to artificial reef.

Results

2

What did we get?

1Fisheries and Management in the Guangdong Province, China: Challenges and Recent Developments

2Evaluating the Efficacy of Artificial Reefs in the Guangdong Province, China: A Case study Using Yangmeikeng Artificial Reef

1Fisheries and Management in the Guangdong Province, China: Challenges and Recent Developments

Rich biodiversity, high valuation

Rich biodiversity: fish species – 229, shellfish species – 84 ， cephalopodium species – 17, （ Jia et al. ， 2012 ）

Fishery Production Ecnomic valuation

1% 2%

9%3%

6%

18%

15%

19%

20%

4% 3%

天津 河北

辽宁 上海

江苏 浙江

附件 山东

广东 广西

海南

0%2%

10%1%

5%

23%

14%

21%

13%

6%4%

0% 2%

8%0%

5%

23%

16%

20%

12%

6% 8%

1990

2000

2010

The figure showed the China’s fishery economic valuation from 1990 to 2010

Guangdong

1992

1993

1994

1996

2000

2002

2003

2004

2005

2006

2007

2008

2009

2010

2011

0

20

40

60

80

100

120

140

160

年份 , Year

产值，亿元

Fishery economic valuation of Guangdong province from 1992 to 2011

Ten billions

Commercial fisheries Commercial Fisheries – trawl, gillnet, trap,

landline Fishery species – fish, shrimp, crab, shellfish…

50’ - 70’

80’ – to now

Challenge Environmental pollution

Challenge Fishery resource decrease Sea-related projects Red tide

1980s 起

Year CPUE (kg/h) Catch (104 tons / Year) High value Trash fish 1970s: 207.26 150 90% 5% 2000s: 30.62 340 15% 80%

以南海为例（潜在渔获量 224~260 万吨）：

近海渔业资源质量下降 产卵场栖息地生态恶化

捕捞过度 环境污染 作业破坏

营养级下降

Total catch in Guangdong Province

1950

1953

1956

1959

1962

1965

1968

1971

1974

1977

1980

1983

1986

1989

1992

1995

1998

2001

2004

2007

2010-300000

200000

700000

1200000

1700000

2200000Other species

Macroalgae

Shellfish

Shrimp&Crab

Fish

Year

Catc

h,

tons

The catches of fishery resource in Guangdong province China

Data collection - Fisheries Statistical Yearbook Data – catch from 1950 to 2010

CPUE

1986

1987

1988

1989

1990

1991

1992

1993

1994

1995

1996

1997

1998

1999

2000

2001

2002

2003

2004

2005

2006

2007

2008

2009

2010

0

50

100

150

200

250

300others Line@angle stow net Gill net

Pursue Trawl

Year

CP

UE,

Tons p

er

vessel

The fluctuation of CPUE of different fishing methods

Vessel

1953

1956

1959

1962

1965

1968

1971

1974

1977

1980

1983

1986

1989

1992

1995

1998

2001

2004

2007

2010

0

20000

40000

60000

80000

Unmotorized vessel

Motor vessel

Year

Fis

h V

essel

Conclusion From 1950 to 1980 catch of fishery in Guangdong

Province was growth slowly. The catch have changed dramatically since

1980’s. The steeply increasing was shown from 1981 to

1998. The total catch has more than four times since 1980 to 1954500 Tons in 1998.

Since then, the obvious decrease was shown. In recent years catch increased slightly

Fisheries management strategies in Guangdong province:

China’s Summer Fishing Moratorium (Close Season)

Object – Protect the fishery resource, sustainability… Initial - 1999

Fisheries management strategies in Guangdong province:

Stocking enhancement Object: restoration of fishery resource Initial: 1980, large scale from 2001 Species : fish, shrimp, shellfish, sea turtle,

macroalgae… Up to dozens of varieties…

Fish

•Lutianus argentimaculatus, Lutjanus sanguineus, Acanthopagrus schlegel, parus latus, Plectorinchus cinctus

shellfish

•Chlamys nobilis, Meretrix meretrix, Paphia undulata, Mactra antiquata

Macroalge

•Porphyra sp., Gracilaria sp., Laminaria japonica, Sargassum sp.

Shrimp

•Penaeus monodon, Penaeus japonicus, Fenneropenaeus chinensis, Penaeus （ Fenneropenaeus） Penicillatus, Penaeus merguiensis

Why we selected these species

Local species

Economic evaluation

Food web: feed…

SeedBiodiversity

When we stocking…During stocking the fishery is closed Time: China’s Summer Fishing Moratorium in

2008 Why: prevent the larval from fishermen Release fishing festival: Promot, Spur

No. Species Quantity, million per year1 花鲈 Lateolabrax japonicus 4 2 青石斑鱼 Epinephelus awoara 2 3 斜带石斑鱼 Epinephelus coioides 14 卵形鲳鲹 Trachinotus ovatus 25 军曹鱼 Rachycentron canadum 0.56 大黄鱼 Pseudosciaena crocea 2 7 紫红笛鲷 Lutianus argentimaculatus 28 红笛鲷 Lutjanus sanguineus 29 星斑裸颊鲷 Lethrinus nebulosus 210 真鲷 Pagrus major 311 平鲷 Rhabdosargus sarba 412 黑鲷 Acanthopagrus schlegel 413 黄鳍鲷 Sparus latus 314 断班石鲈 Pomadasys hasta 215 三线矶鲈 Parapristipoma trilineatus 416 花尾胡椒鲷 Plectorinchus cinctus 1.8 17 斑节对虾 Penaeus monodon 50 18 日本对虾 Penaeus japonicus 50 19 中国对虾 Fenneropenaeus chinensis 20 20 长毛对虾 Penaeus （ Fenneropenaeus ） Penicillatus 100 21 墨吉对虾 Penaeus merguiensis 100 22 杂色鲍 Haliotis diversicolor 0.5 23 华贵栉孔扇贝 Chlamys nobilis 300 24 文蛤 Meretrix meretrix 400 25 波纹巴非蛤 Paphia undulata 300 26 西施舌 Mactra antiquata 20 27 绿海龟 Chelonia mydas 0.0028 28 中国鲎 Tachpleus tridentatus 4 29 大珠母贝 Pinctada maxima 1.6 30 紫菜 Porphyra sp. 431 宽额鲈 Promicrops lanceolatus 0.232 黄唇鱼 Bahaba flavolabiata 0.233 海萝 Gloiopeltis sp. 234 蜈蚣藻类 Grateloupia sp. 135 江蓠类 Gracilaria sp. 436 麒麟菜类 Eucheumae sp. 237 海带 Laminaria japonica 1.538 马尾藻类 Sargassum sp. 639 蕨藻类 Caulerpa sp. 2

the plan of stocking enhancement in Guangdong province from 2010 to 2015 (Chen et al., 2009)

Fisheries management strategies in Guangdong province:

Artificial reef construction History: Rich experiences of artificial reef

achieved in Guangdong during 1981-1985, large scale construction from 2001 - Plan of artificial reef deployment

Construction schedule and scale

2000 2002 2004 2006 2008 2010 20120

50

100

150

200

250

0

20

40

60

80

100

120

140

160

180

200

Reef area

Construction area

Year

Re

ef

vo

lum

e,

10

5 m

3

Co

nstr

ucti

on

are

a,

km

2

Fisheries management strategies in Guangdong province:

Other management strategies

MPA – 1983-1990 (5), 1990 – 1998 (3), 1999 – 2003 (24)…

Fishing license Limit fishing (catch limit) Minimum legal size Gear constraint (mesh size) Buy-back (vessel) and substities (not to fish) Marine ranching combined with habitat

enhancement

1949 1959 1969 1979 1989 1999 20090.00E+00

5.00E+05

1.00E+06

1.50E+06

2.00E+06

2.50E+06

Year

Catc

h,

tons

Close season

Stocking enhancement

Artificial reef

The catch of Guangdong province from 1950 to 2010

Discussion: it works or not…

1985

1987

1989

1991

1993

1995

1997

1999

2001

2003

2005

2007

2009

0

5000

10000

15000

20000

25000

30000

Year

Garo

uper,

Tons

Catch of grouper from 1982 to 2010

1985

1987

1989

1991

1993

1995

1997

1999

2001

2003

2005

2007

2009

0

5000

10000

15000

20000

25000

30000

35000

40000

45000

50000

Year

larg

e y

ellow

cro

aker,

Tons

Catch of large yellow croaker from 1982 to 2010

1978

1980

1982

1984

1986

1988

1990

1992

1994

1996

1998

2000

2002

2004

2006

2008

2010

0

5000

10000

15000

20000

25000

30000

35000

40000

45000

50000

Year

Shri

mp,

Tons

Catch of shrimp

Guangdong’s coastal fishery

was overfishing

Fisheries management strategies in Guangdong province is

working now…

• Fishery resource increasing

• Environmental • Water quality• Others

Which one is best ？

• Stocking enhancement

• Close season• Artificial reef

construction• Others

How and when?

We expected…

2Evaluating the Efficacy of Artificial Reefs in the Guangdong Province, China: A Case study Using Yangmeikeng Artificial Reef

Survey Station design: how to select the station

Reef unit

Difference of reef structure

reef modules

Reef set

The same reef unit or difference reef unit, a large scale

Reef group

Many reef sets, different reef unite and reef set

Reef complexAssembling more than one group into coherent layout

The influence of water current

Water nutrition and fish…

Yangmeikeng Artificial reef

Construction time: Mar 20, 2007 to Dec 25, 2007 Reef Area: 2.65 km2

Construction scale: 12 type reef; 2272 reef, 18 reef group;

Reef volume: 95 100 m3

01号鱼礁

02号鱼礁

03号鱼礁

04号鱼礁

05号鱼礁

06号鱼礁

07号鱼礁

08号鱼礁

09号鱼礁

10号鱼礁

11号鱼礁

12号鱼礁

Reef modulesin Yangmeikeng reef

Reef groupin Yangmeikeng reef

Reef group 1

Reef group 2

Reef group 3

Reef complexin Yangmeikeng reef

Survey station in Yangmeikeng reef

Data source: which style data we need

Survey data: trawl, gill net… Historical data: trawl, gill net Survey time: Mar 2007 (control survey); Mar,

May, Aug, Nov 2008 and May 2009

Trawl data preliminary results

167 species fishery resoruce: 74 fish, 30 crab, 4 shrimp, 8 cephalopod, 35 scallop.

0

5

10

15

20

25

30

35

本底调查 1第 次跟踪 2第 次跟踪 3第 次跟踪 4第 次跟踪 5第 次跟踪

()

渔获种数种

游泳生物底栖贝类

Survey fishery species in Yangmeikeng reef

1.5 - 1.8 times

0

500

1000

1500

2000

2500

3000

3500

4000

4500

本底调查 1第 次跟踪 2第 次跟踪 3第 次跟踪 4第 次跟踪 5第 次跟踪

(kg/

km资源密度

2 )

总渔获游泳生物底栖贝类

0

50000

100000

150000

200000

250000

300000

350000

400000

450000

500000

本底调查 1第 次跟踪 2第 次跟踪 3第 次跟踪 4第 次跟踪 5第 次跟踪

(/k

m尾数资源密度尾

2 )

总渔获游泳生物底栖贝类

2.72 – 8.10 times

4.68 – 17.48 times

0

5

10

15

20

25

本底调查 1第 次跟踪 2第 次跟踪 3第 次跟踪 4第 次跟踪 5第 次跟踪

()

渔获种数种

0

5

10

15

20

25

30

本底调查 1第 次跟踪 2第 次跟踪 3第 次跟踪 4第 次跟踪 5第 次跟踪

(kg/

hm渔获率

2 h)

4.17 – 13.26 times

Gill net data;Total 75: 59 fish, 3 shrimp, 7 crab, 4 squila, 2 cephalopod

1.57 – 3.14 times

0

100

200

300

400

500

600

本底调查 1第 次跟踪 2第 次跟踪 3第 次跟踪 4第 次跟踪 5第 次跟踪

(/h

m尾数渔获率尾

2 h)6.16 – 13.04 times

Further analysis: Regression Tree will be used to analysis the catch data. – VERY VERY PRELIMINARY FOLLOW.

Yangmeiken Sampling areas (10-20 m depth)

? ? ? ?

? ?

? ? ?

? ?

? ? ?

大鹏澳

22º 30′

22º 35′

22º 40′

22º 45′

22º 50 ′N

114º 30′ 114º 35′ 114º 40′ 114º 45′ E

亚

大

湾

深

圳

市

惠阳

市 惠

东

县

范

哑 铃 湾

和港

Dapeng Ao

HuiYang City

ShengZhen City

YaLing Bay

HuidongTown

114º 33′

22º 33′

114º 36′

22º 36′

调控礁区1

2

3

4

5

6

7

8

910 12

11

Sampling Station调查站位

礁区

杨梅坑Yangmeiken

? ? ? ?

? ?

? ? ?

? ?

? ? ?

大鹏澳

22º 30′

22º 35′

22º 40′

22º 45′

22º 50 ′N

114º 30′ 114º 35′ 114º 40′ 114º 45′ E

22º 30′

22º 35′

22º 40′

22º 45′

22º 50 ′N

22º 30′

22º 35′

22º 40′

22º 45′

22º 50 ′N

114º 30′ 114º 35′ 114º 40′ 114º 45′ E114º 30′ 114º 35′ 114º 40′ 114º 45′ E

亚

大

湾

深

圳

市

惠阳

市 惠

东

县

范

哑 铃 湾

和港

Dapeng Ao

HuiYang City

ShengZhen City

YaLing Bay

HuidongTown

114º 33′

22º 33′

114º 36′

22º 36′

调控礁区1

2

3

4

5

6

7

8

910 12

11

Sampling Station调查站位

礁区

杨梅坑Yangmeiken

Yangmeiken Artificial reefs were deployed in 2008.

Both trawl and gillnet surveys were conducted before and after the effect.

2007: 1 survey (Apr)2008: 4 surveys (Mar, May, Aug, Nov)2009: 1 survey (May)

Sampling area Trawl Stations: 1, 4, 5, 6, 7 ,10, 11, 12

Gillnet Stations: 4, 7

Note: fishing activities are prohibited in reef areas. Survey was conducted near reef.

? ? ? ?

? ?

? ? ?

? ?

? ? ?

大鹏澳

22º 30′

22º 35′

22º 40′

22º 45′

22º 50 ′N

114º 30′ 114º 35′ 114º 40′ 114º 45′ E

亚

大

湾

深

圳

市

惠阳

市 惠

东

县

范

哑 铃 湾

和港

Dapeng Ao

ShengZhen City

YaLing Bay

HuidongTown

114º 33′

22º 33′

114º 36′

22º 36′

调控礁区1

2

3

4

5

6

7

8

910 12

11

Sampling Station调查站位

礁区

杨梅坑Yangmeiken

? ? ? ?

? ?

? ? ?

? ?

? ? ?

大鹏澳

22º 30′

22º 35′

22º 40′

22º 45′

22º 50 ′N

114º 30′ 114º 35′ 114º 40′ 114º 45′ E

22º 30′

22º 35′

22º 40′

22º 45′

22º 50 ′N

22º 30′

22º 35′

22º 40′

22º 45′

22º 50 ′N

114º 30′ 114º 35′ 114º 40′ 114º 45′ E114º 30′ 114º 35′ 114º 40′ 114º 45′ E

亚

大

湾

深

圳

市

惠阳

市 惠

东

县

范

哑 铃 湾

和港

Dapeng Ao

ShengZhen City

YaLing Bay

HuidongTown

114º 33′

22º 33′

114º 36′

22º 36′

调控礁区1

2

3

4

5

6

7

8

910 12

11

Sampling Station调查站位

礁区

杨梅坑Yangmeiken

Sampling methodTrawl Gillnet

Identify species

All catch All catch

Sampling catch (in no and weight)

Most fish were 100% sampled or subsample (25%).Crustacean were either 100% sampled or subsampled (6%, 12.5%, or 25%)

100% sampled

Individual length and weight

Max and min Max and min

Trawl survey data

Gillnet survey data

Trawl survey data – Regression Tree

Fish sets (included all species)CPUE ~ Year + season + Station, CPUE=no/swept_area(km2)

S1,S4,S5,S7,S10,S11,S12

S1,S4,S5, S11,S12

S7, S10

S6

S6, 2007

S6 2008, 2009,Season 1, 2 ,3

S6 2008, 2009,Season 4

Fit all data (largest tree)

Cross-validation

Pruned tree based on the min deviance

Gillnet survey data – Regression Tree

S4

S4

S7, 2007

S7

S7, 2008, 2009,Season 1, 2

S7, 2008, 2009,Season 3, 4

Fit all data (largest tree)

Cross-validation

Pruned tree based on the min deviance

Fish sets (included all species)CPUE ~ Year + season + Station, CPUE=kg/swept_area(km2)

Conclusion

3

What will we get from the data？

Conclusion

Management measures were taken to protect the fishery resources – closed season, habitat enhancement, stock enhancement.

The catch of three species of fish increased after the manage measures were adopted.

Preliminary regression tree analyses also detect changes in catch associated with the implementation of habitat and stock enhancements. Further analyses on the full data set are required to look for benefits.

Additional modifications to the existing surveys may be required to collect necessary data to assess benefits (e.g. size data).

Work plan

4

What will we do next step？

Future work plan Complete paper describing fisheries management

in Guangdong Province – publish in scientific journal

Conduct additional data mining of the Guangdong Prov. artificial reef survey data as well as fishery data.

Extend Regression Tree analyses to determine effects of the adopted fisheries management measures (habitat and stock enhancement)

Publish results of analysis in scientific journal. Develop stock assessment models for reef

species in Guangdong province that specifically account for habitat and stock enhancements.

Bottlenecks Based on the Hawaii experience:

o Time – one month exchanges is not long enough to conduct the work. Exchanges should be three months.

o Support – sufficient financial support will be required to conduct exchanges.

o Data – a data exchange-sharing agreement should be established

o Monitoring – monitoring of existing reefs is not conducted. To conduct assessments a long-term monitoring program should be established.

Thanks!