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Tuyen Up Hi»i nghj KHOA HQC T O A N Q U O C V £ SINH HQC BifeN VA P H A T T R I ^ N B £ N VLfNG

HIEN TRANG KHAI THAC VA PHAN PHOI TOM SU
(PENAEUS MONODON) BO ME VUNG BIEN PHIA NAM
VA TAY NAM DONG BANG SONG CUU LONG
Chau Tai Tao, Hoang Van Siiy, Tran Ngpc Hai va Nguyen Thanh Phirong
Dai hoc Cdn Tha

I. M O DAU
Ca Mau l i mot trong nhiing ngu trudng khai thic bien vao loai dirng diu ca nude, cd tiem
nang ddi dao, vi viy ma nghe khai thac bien hien nay rit da dang va phong phu. Khai thic tdm
sii bd me hien nay cung la mpt trong nhirng nghe quan trpng, vira dem lai Igi nhuan cao cho ngu
dan, vira gdp phan cung cap tdm bd me cho nghe sin xuit tdm gidng va nudi tdm d Ca Mau va
Ddng bang Sdng Cim Long ndi chung. Hien nay, ci nude cd khoang 4.281 trai san xuat ban 28,8
ti con tdm gidng, trong dd, DBSCL cd tren 1200 frai v i sin lugng tren 11 ti tdm bdt cung cap
cho nghe nudi (Bd Thiiy sin 2006). Trong sin xuit gidng tdm sii vin de quan trgng nhit la chit
lupng tdm sii bd me la mgt trong nhiing nguyen nhan chinh se quyet djnh den sy thanh cdng hay
thit bai ciia trai sin xuat gidng. Hien nay, hiu het cac trai sin xuit gidng deu phai le thudc vao
ngudn tdm bd me khai thac ty nhien, mac dii mpt sd trai da sir dung ngudn tdm trong dam de
nudi vd thanh tdm bd me (Le Xuin Sinh, 2002). De dap img dugc nhu ciu dd thi nghe khai thic
tdm su bd mp ngiy cing phat trien hon. Hien tai cd rit it thdng tin ve tinh hinh khai thac va sir
dung tdm sii bd me d DBSCL. Chinh vi the, nghien ciru nay dugc thyc hien nham gdp phin
cung cap thdng tin lien quan den hipn trang khai thic, phin phdi tdm sii bd mp d DBSCL lam ca
sd cho quan ly, bio ve va sir dyng hgp ly ngudn tdm sii bd mp nay cho phat trien san xuat tdm
gidng vi nudi tdm sii ben virng d Ci Mau ndi rieng va DBSCL ndi chung.
II. PHI/ONG PHAP NGHIEN CLTU
1. Dja diem va thdi gian nghien ciru
Dieu fra ve hien frang khai thic vi phin phdi tdm su dugc thyc hien tai cua bien Rach
Gdc, huyen Ngpc Hien, tinh Ca Mau tir nam 2007 din nam 2008.

Sd lieu thir cip dugc thu thip tir cac bao cio ciia co quan ban nganh dja phuong va tram
kiem djch thiiy sin tai Rach Gdc. Sd lieu so cip dugc thu thap bang phuong phap phdng vin
fryc tiep ngiu nhien cic tau khai thic (32 tiu), co sd thu mua tdm sii bd mp (23 dai ly cap 1 va
13 dai ly cip II), sir dyng bang cau hdi da soan sin. Cic thdng tin so cip chinh cin thu thip gdm
ngu trudng, miia vy vi ngu cy khai thic, sd lugng tdm khai thic, each tieu thy, gia ban, tinh hinh
phin phdi tdm su bd mp.
Cic sd lieu so cap va thir cip dugc cap nhit vi tinh toan gia frj trung binh, do lech chuan,
ldn nhat, nhd nhit vi phan tich dya tren phin mem Excel.


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HI. KET QUA VA THAO LUAN
1. San luong khai thac torn sii bo me
1.1. Sdn luang torn su bo me khai thdc qua cdc nam
Theo Sd Thiiy sin Ca Mau (2006) bat diu tir thing 8/2006 thi tat ca tdm su bo me khai thic
tir biln phai dugc kiem djch, sach benh mdi dugc dua vao frai san xuat gidng v i phin phdi ra
cac tinh.
Sd lugng tdm sii bd mp khai thic dugc tang nhanh chdng qua cic nam dac biet li frong nam
2007 vi 2008 (hinh 1). Cu the nam 2008 sd lugng tdm sii bd mp khai thic dugc li 138.631 con
trong dd cd 101.409 con tdm cai va 37.222 con tdm dye. Dieu niy vira phan inh nhu ciu ve tdm
bo me cho cic trai gidng la rit ldn va ngiy cing cao, vira cho thiy boat ddng nang ddng ciia
nghe khai thic. Qua khio sit cho thiy nhirng nam trudc diy ngu din khai thic theo miia va theo
con nude thiiy trieu, cdn hien nay hp khai thic hiu nhu quanh nam. Mgt diem rit quan trpng la
ngu cy vi ky thuat khai thic tdm su bd me ngay cing hien dai hon, ngu din khai thic ngiy cing
nhieu do do sin lupng tdm sii bd me tang cao qua cic nam. Ket qui tren cung cho thiy ip lyc
len ngudn lgi tdm bd me ty nhien cung ngay cing ldn.


Hinh 1. Sy gia tang san lu'O'ng torn sii b6 m? khai thac qua cac nam
Theo Withyachumnamkul (2000) thi sy gia tang khai thic ngudn tdm sii bd me ngoai ty
nhien fren toin the gidi de cung cip cho cac trai sin xuit gidng da lim giim di ngudn lgi tdm sii
bo me ngoai ty nhien va gia tdm sii bd me tang cao lim inh hudng den hipu qua sin xuit cua cac
trai gidng.
1.2. Sdn luang torn su bo me khai thdc duac qua cdc thdng trong nam 2008
So lugng tdm sii bo me khai thic nam 2008 li rit Idn, cy thi la 101.409 con tdm cii v i
37.222 con tdm dye (hinh 2). Ngu din khai thac quanh nam nhung cic thing cd lugng tdm khai
thac nhieu nhit la tir thing 11 din thing 5 nam sau, trong dd thing 2 cd sd lugng tdm khai thic
Idn nhit li 12.868 tdm cii va 5.261 tdm dye cdn so tdm khai thic dugc it nhit la thing 9 vdi
5.311 tdm cai va 1.634 tdm dye.


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Tuyen tJp HOi nghj KHOA HQC T O A N Q U 6 C V ^ SINH HOC B I £ N V A P H A T T R I ^ N B £ N VCTNG

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12000
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8000

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2000
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Hinh 2. SIP bi4n 6gi\g san lu>(7ng tom sii bd mf khai thac nam 2008

Trong tdng sd tdm bd mp khai thac dugc tap trung tai Rach Gdc - Ca Mau nam 2008, so
tdm bin ra cic tinh ngoai Ca Mau cd qua kiem djch la 13.410 tdm cai va 6.624 tdm dye, phin
ldn tdm cdn lai dugc sir dyng cho cic frai gidng trong tinh Ca Mau.
2. Tinh hinh khai thac tom sii bo mf
2.1. Luc luang vd ngu trudng khai thdc
Ket qua dieufracho thiy da sd dan khai thac tdm su bd mp den tir tinh Bac Lieu ma t^p
trung 84% la ngu dan tir thj xa Bac Lieu va sd cdn lai nam rii rac d cic huyen Vmh Lgi (9%),
Hda Binh (3%) va Hp Phdng (3%). Hipn nay ngu trudng khai thic tdm su bd mp chu yeu la vimg
bien phia Nam va Tiy Nam DBSCL, noi cd dp sau khoang 30m vi nen day cat. Theo Motoh
(1981) thi tdm khi den tudi trudng thanh di chuyen den bien siu cd khi den 162m, thudng la 2070m de sinh sin. Theo Pomlerd et al. (2005) thi khi khai thac tdm su bo mp d nhirng viing nude
sach cd nen day cat xa bd, dp siu tir 30-60m thi thu dugc nhiing tdm cd chat lupng tdt va ngu cy
bang ludi re cd the lam giam thieu xay sit dan tdm sii bd mp.
2.2. Ngu cu vd miia vu khai thdc
Loai phuong tien khai thac tdm bo mp chinh la cic tiu cd cdng suit tir 90 CV trd len vdi
ngu cy khai thac la ludi re 3 mang cd chieu dai trung binh 9.372±2.482m va chieu sau frung binh
3,3±0,5m vdi mat ludi ngoai ciing 2a la 28,3±2,4cm, mit ludi thin 2a la 8,6±0,8 cm. Khi ludi
dugc tha xudng bien thi cic mang se hinh thanh tui ludi cd kha nang biy dugc nhieu kich cd tdm
(80-300g/con). Hoat dgng khai thac tdm su bd me cua ngu din dien ra lien tuc cac ngay trong
thing. Mdi ghe khai thac tha va thu ludi mpt lin/ ngay, khi thiiy trieu bit dau len cung la luc ngir

din rii ludi va den khi thiiy trieu xudng thi tien hinh len ludi thu tdm. Tdm su bd mp dinh bat
thudng dugc thi vio thiing xop cd chay may syc khi chd cic ghe cua dai ly cap I ra thu gom va
van chuyen vao dit lien. Miia vu khai thic hien nay la quanh nam, nhung nang suit bien dgng
theo miia hay thdi tiet va nhu ciu sir dyng tdm sii bd me tir cac trai gidng.


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3. Gia ban torn sii bo mf tai ngu trudng
Qua kit qiia dieu tra 32 tau khai thic thi gii ban tdm cii tnmg binh li 709.375±588.250
d/con (biln ddng tir 150.000- 3.000.000d) va gii tdm dye frung binhli 34.063±18.608 d'con (tir
10.000-1 OO.OOOd). Gii tdm bd me phy thudc vio thi frudng, miia vu vi chit lugng tdm bd me.
Hien nay tai cira bien Rach Gdc cd 23 dai ly cap I vi 13 dai ly cap II thudng xuyen kinh doanh
tdm su bd me dinh ky 2-3 ngay mgt chuyen di tren bien va mpt vai co sd kinh doanh nhd le
(khdng dang ky hinh nghe).
3.1. Kenh phdn phoi torn su bo me
Nghe khai thic tdm sii bd me ciia C i Mau phit frien khoang tir nam 2003 v i noi cd boat
ddng thi trudng mua bin tdm sii bd me sam uat nhit Ii cira bien Rach Gdc thudc xa Tin An,
huyen Ngpc Hien. Kenh phin phdi tdm sii bd me theo so dd sau:
3.2. Dgi ly cap I
Dai ly Cip I dugc hieu li noi thu gom tdm bd me tir ngu din khai thac va mdi dai ly cd mgt
hoac nhieu ghe (tir 1-3 chiec), hp cd cano vdi cdng suit Idn hoat ddng tren bien, chay ra ngu
frucng mua tryc tiep tir ngu dan khai thic. Hiu het cic ghe khai thic chi vao bd khi cin thiet
nhu cic trudng hgp sira chira miy mdc, ngu cy hay ngu din dau dm benh tit. Nhung nhu ciu
khic nhu luong thyc, thyc phim, nhien lieu dugc mua tryc tiep tir cac ghe thu mua cua dai ly
cip 1 mang ra cung cip ngoii bien. Sd chuyen cua cic tiu dai ly cip I ra bien thu gom tdm vio
khoing 6±1 chuyen/thing (tir 3-18 chuyen/thang) vi lugng tdm mua trung binh 44±12
con/chuyen (25-70 con/chuyen). Nhu viy, trung binh mdi thing mpt tau thu mua dugc 162±63

con (dao ddng tir 80-360 con/thing). Ngudn tdm bd me khdng dn djnh v i ngu trudng khai thic
nam xa bd nen cac dai Iy cip I ludn tiic tryc thu gom va chuyen tdm ve ngay. Tdng sd tdm bd
me mi mdi dai Iy cip I thu mua dugc trung binh li 4.277±3.604 con/nam (1.200-15.480
con/nam). Sd lugng tdm cii dugc dai Iy cip I cung cap cho cic trai gidng va dai ly cip II cung
nhu nhirng ngudi mua khic frung binh li 3.343±2.934 con/nam (800-16.800 con). Sd lugng tdm
dye dugc dai ly cap I phin phdi trung binh 935±702 con/nam (200-3.360 con).. Nhu viy, sd tdm
cii dugc dai Iy cip I phin phoi chilm 78%, v i tdm iuc Ii 22%. Tdm me phan phdi tir cic dai ly
cap I tryc tilp cho cac trai giong la 7.688 con/nam (10%) v i dai ly cip II trung binh 69.192
con/nam (90%). Trong nam 2007 thi tdng sd tdm bo mp ma tat ci cic dai ly cip I phin phdi
khoang 98.375 con/nam trong dd tdm cii la 76.880 con/nam (78,15%) va tdm dye li 21.495
con/nam (21,85%). Gii frung binh mdi tdm cii 826.087±407.771 dong (tir 350.000-3.000.000d),
tdm cii cd gia dudi mirc trung binh chung chiem 61% va fren mu:c trung binh chiem 39%. Gii
moi tdm dye tinng binh 78.043±32.604d (tir 30.000-200.000d), tdm dye cd gii dudi mirc trung
binh chung chiem 48% va fren mirc trung binh chung chiem 52%.


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Tuyen tgp H$i nghj KHOA HQC T O A N Q U Q C Vfe SINH HOC B I £ N V A P H A T T R I E N B £ N VCfNG

";

N g u dan khai t h a c
i

Dai ly cap 1 thu g o m tren bien


•i

Dai ly c a p 2

Trai gidng trong tinh
(Ck Mau)

Trai giong c i c tinh lan can
(Chu yeu la Mien Trung)

Hinh 3. Sa dd kenh phan phoi torn su bd mf

3.3. Dgi ly cap II
La CO sd thu mua tir dai ly cap I de ban cho cac frai gidng hoac phan phdi di cac dja phuang
khac d DBSCL, cho cac thuang Iii va cho cac co sd sin xuit tdm gidng d mien Trung. Dai ly cap
n la noi thu mua tdm phin phdi chu yeu ngoii tinh nen thudng thu tdm cd nhieu ngudn gdc va
nudi giir lai vdi mat do tuong ddi day, dieu niy lam tang khi nang liy nhiem benh ciia tdm bo mp.
Sd lugng tdm cii dugc dai ly cip II cung cip cho cic frai gidng va cac td chirc ca nhin khac
cd nhu ciu trung binh Ii 5.785±4.036 con/nam (tir 1.650-13.500 con/nam). Sd tdm cai dugc
phin phoi ngoai tinh la 4.57I±3.706 con/nam chiem 73,3% vi trong tinh la 1.213±779 con/nam
chiem 26,7%. So tdm dye trung binh la 1.596±1.133 con/nam (325-3.500 con/nam). Lugng torn'
bd mp cua tat ca cac dai ly cap II cung cap la 88.538 con/nam, trong do tdm cai 69.192 con/nam
(78,15%) vatdm dye 19.346 con/nam (21,85%). Gii bin tinng binh 1.321.145d/tdm cai (tir
600.000-2.400.000d/con) va 109.615 d/tdm dye (100.000-125.000d/con). Tdm cai cd gia dudi
mirc trung binh chiem 46% va tren mirc trung binh Ii 54%, ddi vdi tdm dye ty lp nay lan lugt la
62%vi38%.
TV. KET LUAN
Sin lupng tdm sii bo me khai thic dugc tang nhanh trong nhirng nam gin diy va miia vv
khai thic hiu nhu quanh nam tuy nhien sin lugng bien ddng theo cac thing trong nam.
Trong nam 2007 thi dai ly cip mpt thu gom vi phin phdi lai cho dai ly cip hai va cac trai

gidng Ii 76.880 tdm cii vi 21.495 tdm dye vdi gii ban trung binh la 826.087±407.771 ddng/tdm
cii vi 78.043±32.604 ddng/tdm dye. Trong khi dd thi dai ly cip hai phan phoi dugc 69.192 tdm
cii va 19.364 tdm dye vdi gii ban Ii 1.321.154±576.795 ddng/tdm cii vi 109.615±12.659
ddng/tdm dye.
Nim 2008 khai thic dugc 101.409 tdm cii vi 37.222 tdm dye. Trong sd niy, tdm ban ra
ngoii tinh Ca Mau cd qua kiem djch la 13.410 tdm cii vi 6.624 tdm dye, phin Idn tdm cdn lai
dugc sir dung cho cic frai gidng trong tinh.


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207

V. TAI LIEU THAM KHAO
1. Bd Thiiy sin. 2006. Bio cio dinh gii ket qui thyc hien chuong trinh phit triln NTTS giai
doan 2000-2005 va bipn phap thyc hien din nam 2010. Ha Ngi, thing 3 nam 2006.
2. Le Xuan Sinh. 2002. Tdm bd me sir dyng frong frai sin xuit gidng. Tap chi Thuy sin so 6,
2002. Bp Thiiy sin, tr.l 1-14.
3. Motoh. 1981. Aquaculture Deparment Southeast Asian Fisheries Development Center,
Iloilo, Philippine.
4. Pomlerd, Chanratchakool, Flavio, Corsin and Matthew Briggs, 2005. Hudng din thyc hanh
quan ly tdt (BMP) frong trai san xuat tdm sii gidng tai Viet Nam. Bp Thiiy sin Viet Nam
phoi hgp thyc hien, thing 12 nam 2005.
5. Sd Thiiy sin Ca Mau, (2006). Mpt sd vin de khai thac, quan ly tdm bd me vi sin xuit gidng
tdm sii tai chd d Ca Mau. Hgi nghj ban ve giai phap phat trien nudi trong thiiy sin ben vimg
cic tinh Nam Bd
6. Withachumnamkul B, P. Plodphai, G. Nash and D. Fegan. 2000. Performances of
domesticated Penaeus monodon broodstock in Thailand. Asian Aquaculture Magazine,
March/ Apnl 2002.


EXPLOITATION AND DISTRIBUTION OF TIGER SHRIMP (PENAEUS
MONODON) BROODSTOCKS THE SOUTH AND SOUTH - WEST SEA
OF THE MEKONG DELTA
Chau Tai Tao, Hoang Van Suy, Tran Ngoc Hai, Nguyen Thanh Phuong
SUMMARY
Demands on wild tiger shrimp (Penaeus monodon) broodstocks for seed production in
Vietnam are increasing rapidly. Rach Goc river mouth of Ngoc Hien District, Ca Mau province
is considered the main place for gathering shrimp broodstocks from fishing boats in the South
and South-West sea of the Mekong Delta and then distribute for seed production on the regional
provinces and the cenfral provinces. This study aims at evaluation of fishing and distribution of
tiger shrimp broodstocks in order to contribute to resources management in the region.
Secondary data were collected from the fisheries station in Rach Goc and primary data were
collected from interviewing 32 fishermen, 23 first distributors and 13 second distributors based
on prepared questionairs.
Results of the study showed that the fishing ground of tiger shrimp broodstocks are in the
South and South - West of the Mekong Delta with sandy bottom and water deptii of about 30m.
Fishermen are mainly from Bac Lieu province. Fishing boats have high capacity of over 90CV
and use drag net as fishing gear. Fishing season is year round, however, production is seasonal.
Number of broodstocks exploited has been increasing rapidly, from totally 40,000 shrimps by
2003 to 101,409 female and 37,222 males by 2008. Of this number, number of shnmp
broodstocks checked for diseases and sold to regional provinces is 13410 female and 6624 male
broodstocks, the most of broostocks are supplied to the hatcheries in Ca Mau province. Average
body weight of the female is 160±14.5g and the male is 96.1±8.30 g. Average selling pnce at


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Tuyln tap HQi nghj KHOA HQC T O A N Q U Q C V t SINH HOC BI^N VA P H A T T R I ^ N B S N VCTNG

fishmg ground is 709,375±588,250 VND/female shrimp and 34,063±18,608 VND/male shrimp.'

By the year 2007, the first distributors sold to the second distributors and the hatchery owners
totally 76,880 female and 21.495 male at average price of 826,087±407,771 VND/female ancj
78,043±32,604 VND/male. Meanwhile, the second distributors sold the broodstocks at
1,321,154±576,795 VND/female and 109,615±12,659 VND/male.
Generally, exploitation and supply of wild shrimp broodstocks are very importance for
shrimp hatchery production in the Mekong Delta. However, this study is calling for more studies
to develop appropriate methods of fishing and conservation while still ensure the development of
shrimp seed production in the region.
^
Keywords: Black tiger shrimp, brood-stock, male, female,
fishing
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