• No results found

Application of remote sensing techniques for locating pelagic fish concentrations along the Kerala coast (SW coast of India) - work done and future prospects

N/A
N/A
Protected

Academic year: 2022

Share "Application of remote sensing techniques for locating pelagic fish concentrations along the Kerala coast (SW coast of India) - work done and future prospects"

Copied!
17
0
0

Loading.... (view fulltext now)

Full text

(1)

Marine

Research and Management

Editors

V.N. Pillai and N.G. Menon

Central Marine Fisheries Research Institute

(Indian Council of Agricultural Research) Tatapuram P.O., Cochin-682 014

Kerala, India

2000

(2)

^ O Application of remote sensing techniques for locating pelagic fish concentrations along the Kerala coast (SW coast of India) - work done and future prospects

V. Narayana Pillai, K.M.Santosh, K.M.Shivaraj and Saji. K.David

ABSTRACT

Intensive validation programme on Potential Fishing Zone fore- casts carried out by the MARSIS, Central Marine Fisheries Research Institute, Cochin, at 17 selectedjish landing centres along the Kerala coast between November 1995 and May 1996 revealed a positive relationship betwen PFZ and occurence/abundance of commercially important pelagic fishes. An attempt is made to identify possible reasons for the above, based on results of oceanographic itivesti- gations undertaken in the area and also taking into consideration fish behaviour in relation to environn-ieni based on past data. Fu-

ture plans for evolving a suitable prediction system for commer- cially important pelagic fishes in the coastal waters of the main- land and skipjack fishery in the Lakshadweep islands based on PFZ forecasts are also discussed in view of its importance to the artisanal and small mechanised sector fishermen for reducing the searching time and thereby effecting an overall reduction in the cost of fishing.

Introduction

Tropical marine fisheries are essentially multispecies and multigear in their char-ictcristics. Tropical fish stocks are distinctly different from their temperate c o u n t e r p a r t s in their behaviour, migration, food and feeding h a b - its, reproduction, recruitment, growth mortality and production.

As a premier nodal institute for marine fisheries research and related biological oceanographic investigations, the Central Marine Fisheries Research Institute (CMFRl) u n d e r Indian Council of Agricultural Research, h a s been

(3)

Marine Fisheries Research and Management

actively collaborating with the Department of Space and the D e p a r t m e n t of O t c a n Development, Govt, of India,in the National Project On "Ocean Related Remote Sensing Programme"

The Marine Satellite Information Service (MARSIS) Programme was ini- tiated by the D e p a r t m e n t of Ocean Development and is being co-ordinated by the National Remote Sensing A g e n c y / D e p a r t m e n t of Space, a s the nodal agency. The other participating agencies are. Space Application Centre (SAC), Ahmedabad, National Institute of Oceanography (NIO) Goa, Centre for Math- ematical Modelling and Computer Simulation (C-MMACS), Bangalore, Orissa State Remote Sensing Application Centre (ORSAC), B h u b a n e s h w a r , Institute for Ocean Management (lOM), Madras and Central Marine Fisheries Research Institute (CMFRI), Cochin. MARSIS h a s the overall objective of developing operational remote sensing capabilities for extraction of coastal zone and oce- anic p a r a m e t e r s and providing d a t a to down s t r e a m u s e r s . Models are to be developed for simulation and prediction of oceanic processes. During the first p h a s e of the programme, which was completed in March 1993, opera- tional p r o d u c t s of sea surface t e m p e r a t u r e (SST) data sets, Potential Fishing Zone (PFZ) advisories and coastal m a p s of Kerala and Tamil Nadu s t a t e s have been g e n e r a t e d a n d d i s s e m i n a t e d . Effective s e a t r u t h d a t a was collected through ship cruises and drifting and moored buoys. The above mentioned MARSIS Centres were implemented and made operational during the first p h a s e . In the second p h a s e , which is u n d e r progress, to be completed in March 1997, operational services such as SST m a p s a n d PFZ advisories have been further s t r e n g t h e n e d .

The total marine fish landing in India was provisionally estimated at 2.36 million tons during 1994 (CMFRI, Annual Report, 1994-95). An increase of 3.5% (80,000 t) over 1993 was observed. Pelagic groups contributed 46.7%

and demersal 5 3 . 3 % . Though there was a n increase of a b o u t 80,000 t in landings during 1994 compared to previous year, the catches of oil sardine, whitebait and mackerel decreased by 4 9 , 0 0 0 t, 12,000 t and 45,000 t respec- tively. The total landings along the SW coast of India h a s shown a decline of 60,000 t during 1994 over those of 1993. Major contributors to the decline were oil sardine, whitebait and mackerel.

The above mentioned figures clearly show the large scale fluctuations observed in the occurence and a b u n d a n c e of selected pelagic fishes along the SW coast of India.

(4)

Application of remote sensing techniques for locating pelagic fish Potential F i s h i n g Zone (PFZ) forecasts and validation

Studies conducted both within the country and abroad have revealed t h a t sea water t e m p e r a t u r e , dissolved oxygen content, salinity, phytoplankton and zooplankton concentrations play a n i m p o r t a n t role in the distribution and a b u n d a n c e of fishery r e s o u r c e s , especially t h e pelagic r e s o u r c e s .

Monitoring t h e s e p a r a m e t e r s in space a n d time is prohibitively expen- sive and a real time picture of any one of these p a r a m e t e r s or a combination of the above becomes almost a n Impossibility. Indirect method of monitoring s e l e c t e d o c e a n i c p a r a m e t e r s s u c h a s s e a s u r f a c e t e m p e r a t u r e a n d phytoplankton pigment a t sea surface from satellites is found ideal as it pro- vides high repetitivlty and large spatial coverage. Timely forecasts of Poten- t i a l F i s h i n g Z o n e s b a s e d on s e a s u r f a c e t e m p a r a t u r e or s e a s u r f a c e p h y t o p l a n k t o n pigment concentration can help in minimising the searching time for fish s h o a l s especially among a r t i s a n a l fishing sector thereby bring- ing down the overall coast of fishing operations.

PFZ advisories are being generated by the National Remote Sensing Agency, Hyderabad, twice a week to over 160 centres all along the Indian coast. Validation campaign are regularly u n d e r t a k e n to e n h a n c e the accu- racy, format and dissemination aspects. PFZ a w a r e n e s s / t r a i n i n g programmes are regularly conducted at various fish landing centres. Institutions s u c h a s CMFRI, FSl and ORSAC and State Fisheries D e p a r t m e n t s are being associ- ated for validation. The CMFRI h a s taken u p a special p r o g r a m m e for the Intensive collection of marine fish catch d a t a on exploited fishery r e s o u r c e s in relalion to PFZ forecasts. Marine fish landing data pertaining to a total of 1300 landing centre's distributed in the various maritime s t a t e s a n d Union Territories distributed is being collected systematically t h r o u g h a network of over 120 trained survey personnel attached to the Institute's h e a d q u a r t e r s a t Cochin a n d 12 Regional/Research Centres.

Even though the dissemination of PFZ forecasts to groups of the active fishermen a n d obtaining feedback from the s a m e g r o u p s w a s t a k e n u p on a priority b a s i s since the beginning of 1993, especially along the Kerala Coast, the r e s p o n s e was comparatively poor mainly b e c a u s e of the fact t h a t , the fishermen were not convinced a b o u t the usefulness of the information pro- vided to them t h r o u g h the PFZ forecasts.

(5)

Marine FiaherieB Research and Management

Since 1995, the MARSIS Centre a t CMFRI. Cochin, organised a n Inten- sive dissemination and feedback d a t a collection programme a t 17 selected landing centres along the Kerala coast, between November, 1995 and May, 1996, the period d u r i n g which PFZ forecasts were given out by NRSA. The forecasts received were t r a n s l a t e d Into the local language and p a s s e d on to the active fishermen. A r r a n g e m e n t s were m a d e t h r o u g h t h e local dally,

"Malayala Manorama" to bring out t h i s information twice a week, immedi- ately on receipt of the forecast from NRSA. A blackboard of suitable size was Installed at the Cochin Fisheries Harbour wherein the salient features of each forecast was given in writing In simple local language. The Information was also b r o a d c a s t t h r o u g h the AIR services at Cochin t h e s a m e evening.

Seventeen fish landing centres such as Kottekkunnu, Kannur, Thalassery, Cowayl, Perlmba, Chombala, Qullandy, P u t h l a p p a , Vellayll, Beypore, Nattika, Azhikode, Cochin, Valanjavazhl, Ambalapuzha, Needakara / S h a k t i k u l a n g a r a and Vlzhlnjam were selected for the compaign mainly b a s e d on the positive r e s p o n s e received from active fishermen groups operating from t h e s e centres.

The location of the above mentioned centres Is given In Fig. 1

F-io.i.-«wiAr» a t - i o i w i N < a L j o c A r r i o i M O F L A M D I M O o c M T R i I M I O N I T O R E D I N T H E f » R E S E M - r S T U i y V A . I . O t 4 Q T H E

(6)

Application of remote sensing techniqneg for locating pelagic fish The feedback Information with details of craft, fishing methodology adopted, fishing gear employed, fishing effort exRen^fid- haulwlse fish catch, specieswise fish catch, location of fishing activity pifijil with depth, d i s t a n c e from the coast a n d bearing were collected from the s a m e group of fishermen on their r e t u r n from fishing activity.

Detailed analysis a n d processing of the basic d a t a w a s u n d e r t a k e n a t the MARSIS Centre a g a i n s t individual PFZ forecast and the validation r e s u l t s were p a s s e d on to NRSA immediately.

R e s u l t s of PPZ v a l i d a t i o n

It Is well known t h a t , the a d a p t a t i o n of fish to the s u r r o u n d i n g m a r i n e environment Is controlled by various physicochemical a n d biological p a r a m - eters. Fishes are known to react to changes in environmental conditions a n d migrate to a r e a s where favourable conditions of sea water t e m p e r a t u r e , dis- solved oxygen levels a n d salinity exist. Availability of food Is a n I m p o r t a n t factor which controls fish occurence, a b u n d a n c e a n d migration. Sea surface t e m p e r a t u r e Is the most easily observed environmental p a r a m e t e r and is quite often correlated with availability of fish, especially pelagic fishes. F l u c t u a - tions in SfsT r e s u l t from changes occurlng in other factors s u c h a s upwelling, eddies etc. Squire (1982), found t h a t many oceanic pelagic species concen- t r a t e a t c u r r e n t b o u n d a r i e s especially In a r e a s with s h a r p horizontal tem- p e r a t u r e gradient. Laurs etal. (1984) found higher c a t c h r a t e s in the vicinity of t e m p e r a t u r e fronts sometimes extending u p t o 100 km offshore from the b o u n d a r i e s of t h e front.

The E u r o p e a n Commission Fisheries Report published by t h e Nansen Centre (Pettersson, 1989) provides an excellent review of the successful u s e of satellite - b a s e d observations in fisheries applications. Fluza (1990) h a s d i s c u s s e d the application of satellite remote - s e n s i n g to fisheries. In Portu- gal the SATOCEAN project h a s since 1989 been providing operational service to t h e P o r t u g u e s e t u n a a n d swordfish fishermen (Santos a n d Fluza, 1992), wherein, fishermen are provided with c h a r t s with location of t h e r m a l fronts and I s o t h e r m s derived from AVHRR d a t a .

The salient r e s u l t s of PFZ validation u n d e r t a k e n by CMFRI, MARSIS Centre a t t h e above-mentioned 17 landing c e n t r e s along t h e Kerala coast be- tween November 1995 a n d May 1996 are given below.

C 4 8 3 ^

(7)

Marine Figherieg Reaearch and Management

a) Positive relationship between PFZ resulting from comparatively high g r a d i e n t s of SST (2"c & above) a n d fishable c o n c e n t r a t i o n s of commercially important fishes were found only In respect of pelagic a n d column fishing activities s u c h as p u r s e seining, gill - netting and trolling especially during the period November 95 to J a n u a r y 96. In t h e case of bottom trawling activ- ity, the relationship was found Lo be negligible or nil d u r i n g the s a m e period.

For p u r s e seine fishing, the average fish catch / b o a t s varied between 4,480 a n d 3,200 kg for PFZ and non-PFZ respectively at Cochin Fisheries Harbour landing centre during the month of November 9 5 , when t h e maxi- m u m n u m b e r of p u r s e - seine b o a t s were operating off Cochin. In the case of gill-net fishing,the s a m e varied between 480 and 187 kg for the s a m e month (Figs. 2 & 3).

In t h e case of bottom trawling, PFZ w a s showing a lesser q u a n t i t y when compared to non-PFZ during the s a m e month (Fig. 4,).

C«tGh/Bott(KgHThouMndt)

NOV96 DECdB JAN'Oe FEB'96 MAR'»e

PURSE SEINE

• PFZ H N Q N - P F Z

FIQ.2.-PFZ VALIDATION, COCHIN FISHERIES HARBOUR

cj8£::>

(8)

Application of remote s e n s i n g t e c h n i q u e s for locating pelagic fish

900

NOVM DECOS JAN'M FEVOe MAFTM

QILL NET

Fia3.-PFZ VIAUOATiOH C60m FI8HCRIi8 HAiRBOUR

Catoh/Boat(Ka)

NOVM DEC^ JArrSS PEB'M MAITM

TRAm. NET

• i P F Z H N O N - P P Z

FIQ.4.-PFZ VALIDATION, COCHIN FISHERIES HARBOUR

(9)

Marine Fisheries Researcband Management

Comparlsln of c a t c h e s obtained for PFZ a n d non-PFZ employing dif- ferent fishing methodologies for t h e m o n t h s Noveml^er 95 j o March 1996 is given in Fig.5.A, to 5.E.

Catch/Boat(Kg) (Thousands)

4 3 2 1 h

4.48

0.48

• | H B 0 ; 1 8 7

I^^Hfcmssssa

GILL NET PURSE SEINE HOOK & LINES NOVEMBER 1996

0.20e 0.26C TRMNL. NET

• • PFZ ^ ^ NON-PFZ

FIQ.5.A.-PFZ VALIDATION. C O C H I N FISHERIES HARBOUR Catoh/Boat(Ko)(Thousand«)

QILLNET PURSE SEINE HOOKS t LINES TR/iVL NET

DECEMBER 1995

• PFZ • NON-PFZ

FiQ.6BrPFZ VALIDATION, COCHIN FISHERIES HARBOUR

(10)

Application of remote aengtng technlqueg for locating pelagic fish Catch/Boat(Ko)

700 600 600 400 300 200 100 0

328 310

GILL NET PURSE SEINE HOOK 4 LINES TR>WL NET

JANUARY 1996

• • P F Z E H N O N - P F Z

FIQ.5.C-PFZ VALIDATION, COCHIN FISHERIES HARBOUR

500 400 300 200 100 0

Catoh/l3oat(Ka)

100 94

370 360

QILL NET PURSE SEINE HOOKS & LINES TRMNl NET

FEBRUARY 1996

• 1 ppz ^ NON-PFZ

Fia5.D,-PFZ VALIDATION, COCHIN FISHERIES HARBOUR

(11)

Marine Flgheries Roearch and Management

GILL NET PURSE SEINE HOOKS & LINES TR««L NET

MARCH 1996

• 1 PFZ ^ NON-PFZ

FIQ.5.E.-PFZ VALIDATION, COCHIN FISHERIES HARBOUR

Details regarding the d u r a t i o n of individual PFZ forecast, total n u m b e r of b o a t s monitored, fishing activity in PFZ a n d non-PFZ, average fish catch / boat in PFZ and non-PFZ, fishing methodology adopted / fishing gear em- ployed a n d catch composition are given in Table 1.

Table 1: Results of the validation of PFZ forecasts carried out by MARSIS Centre of CMFRI, Cochin

Forecast

Date

21-24 N o v ' 9 5 Cochin

21-24 N o v ' 9 5 Cochin

21-24 Nov '95 Cochin

2-4 Dec '95 Cochin

Total no.of Boats

PFZ 1

5

6

I

Monitored non-PFZ

26

9

18

13

Average fish c a t c h / B o a t PFZ

480

4480

208

800

•('""ARR

non-PFZ 187

32000

255

348

Fishing Gear

GN

PS

BT

BT

Fish Catch

Tuna, Seer Fish

Tuna, Seer Fish

Prawn, Sep lA S h a r k s , Carangids, Nemipterus

(12)

Application of remote senglng techniqueg for locating pelagic fish 6-7 Dec'95 1

Cochin

6-7 Dec'95 1 Qullandy

6-7 Dec'95 3 Chombala

6-7 Dec'95 3 Kannur

5-6 J a n ' 9 5 9 Cochin

5-6 J a n ' 9 6 10 Cochin

10-12 J a n ' 9 6 8 Cochin

10-12 J a n ' 9 6 2 Cochin

10-12 J a n ' 9 6 5 Cochin

13-15 J a n ' 9 6 6 Cochin

24-25 J a n ' 9 6 18 Cochin

24-25 J a n ' 9 6 6 Cochin

3-5 Feb'96 2 Beypore

6-9 Feb'96 2 Azhikal

13-15 Feb'96 3 Beypore

150 236

110 89

112 105

18 100 81

13 697 613

422 4 7 5

16 3 5 3 3 0 6

8 375 462

28 539 573

216 450

352 316

14 495 365

14 415 3 5 3

25 132 101

22 380 311

GN Seerfish

RS Sardines

RS Sardines

RS Sardines

BT Nemipterus Priacanthus Perches HL Perches

GN Tuna.Seerfish

HL Perches

BT Nemipterus Saurida

BT Nemipterus

Troll Seerfish T u n a

BT Nemipterus Decapterus Saurida

BT Nemipterus Decapterus BT Decapterus

Nemipterus BT Decapterus

Nemipterus

(13)

Marine Fisheries Research and Management 1 3 - 1 6 F e b ' 9 6 2

C o c h i n

1 3 - 1 6 F e b ' 9 6 5 C o c h i n

1 3 - 1 6 F e b ' 9 6 3 C o c h i n

6 - 8 M a r ' 9 6 2 C o c h i n

1 3 - 1 5 M a r ' 9 6 5 C o c h i n

1 3 - 1 5 M a r ' 9 6 6 C o c h i n

1 3 - 1 5 M a r ' 9 6 4 C o c h i n

1 2 - 1 3 M a r ' 9 6 3

•VFH

1 4 - 1 5 M a r ' 9 6 18 N e e n d a k a r a

2 7 - 2 9 M a r ' 9 6 1 C o c h i n

2 7 - 2 9 M a r ' 9 6 5 C o c h i n

2 7 - 2 9 M a r ' 9 6 5 C o c h i n ,

2 7 - 2 9 M a r ' 9 6 16 C o c h i n

30

3 1

12

3 1 0

1 0 0

590

705

1 0 1

325

VFH= V i z h i n j a m F i s h e r i e s H a r b o u r

2 7 - 2 9 M a r ' 9 6 2 5 11 4 1 8 3 1 2

9 4

3 7 1

386

68

228

HL P e r c h e s

2 3 4 1 1 2 2 8

4 1 3 3

5 6 3 3 1 1

14 3 0 2 4

8 2 9 7

1 9 0 1 6 6

15 2 0 8 1 9 8 ON

BT

BT

S e e r fish, T u n a Nemipterus Decapterus Nemipterus S e p i a , P r a w n s GN T u n a , S e e r f i s h

HL

BT

HL

BT

GN

PS

HL

BT

Epinephelus Pris ti-Pomoides

Nemipterus Decapterus Perches, T u n a

Nemipterus Anchovies Seerfish, T u n a Mackerel

Pristipo- moides.

Kalava Decapterus Nemipterus Squids, Prawns

323 BT Decapterus

(14)

Application of remote s e n s i n g t e c h n i q u e s for locating pelagic fish Neendakara

27-29 Mar'96 Neendakara 30-31 Mar'96 Valanjavazhi 01 APR'96 Thottapalli 01 Apr'96 Chethy 01 Apr'96 Thottapalli 5-6 Apr'96 Beypore 8 Apr'96 Chombala 8 Apr'96 QuUandy

98 101

114 84

143

80 9 3

85 112

15 214 192

2 1 3 150

113 90

HL

MT

HL

DN

GN RS DN

Saurida Anchovies Seerfish Tuna,Perches Decapterus Stoliphores S h a r k s Mackerel RS Decapterus

Mackerel Seerfish,

BT Nemipterus Flatfish

Mackerel Decapterus Decapterus Stoliphores GN : Gill net,PS : Purse Seine, DN : Drift Net,

BT : Bottom Trawling, MT : Minitrawl, RS : Ring Seine, HL : Hooks & Lines

Between the end of February and May '96, with the coastal waters get- ting h e a t e d u p to greater vertical extent caused by s u m m e r h e a t i n g and with the d i s a p p e a r a n c e of high gradients of SST from the area u n d e r s t u d y , m a n y of the commercially important pelagic shoaling fishes like oil sardine [Sardinella lonquiceps], mackerel (RastrelUger kanaqurta) and t u n a s remained in com- paratively deeper w a t e r s thereby getting themselves c a u g h t in bottom trawl- ing gear which cannot be interpreted a s any kind of relationship between sea surface t e m p e r a t u r e and demersal fish. Sloggett et al. (1995) observed that, demersal (Bottom living) fish are equally hkely to thrive at zones of high pelagic production, since their benthic food r e s o u r c e s are directly e n h a n c e d by the high primary production in the euphotic zone.

C i o Q

(15)

Marine Fisherie* Research and Management

b) The s e a t r u t h d a t a collected through the c r u i s e s of FORV Sagar Sampada during different s e a s o n s in the a r e a u n d e r s t u d y clearly revealed factors which contributed towards the formation of high gradients of SST (2°c or more ) characteristics of the m o n t h s , November ' 9 5 , December '95 and J a n u a r y '96,along the Kerala coast. The p r e s e n c e of comparatively strong surface c u r r e n t s caused by the prevailing NE monsoon ( winter monsoon) in the SE Arabian sea which carried comparatively warmer equatorial waters towards n o r t h e r n l a t i t u d e s would have resulted in comparatively high ther- mal gradients in the area u n d e r study. The SST in this area during Novem- ber ' 9 5 - J a n u a r y '96 is comparatively low resulting mainly out of winter cool- ing. When comparatively warmer waters were carried n o r t h w a r d through the winter monsoon circulation, it resulted in strong t e m p e r a t u r e gradients at surface levels in the SE Arabian Sea. This is especially so in the Island terri- tories of Maldives a n d Lakshadweep.

The northerly c u r r e n t became weak and slowly died out during J a n u - ary - February resulting in medium a s well as low t h e r m a l gradients in the locality between February and May. Exceptions were mostly found on the windward side of oceanic islands (Maldives and Lakshadweep) where the di- vergence would have resulted in t h e formation of comparatively high gradi- e n t s of t e m p e r a t u r e . This is clearly revealed from the m a p s of potential fish- ing zones brought out by NRSA between November a n d May, the period dur- ing which the cloud cover w a s comparatively m i n i m u m .

c) Seasonal varitions are characteristic of the thermocline in the e a s t e r n Arabian Sea and western Bay of Bengal bordering the Indian subcon- tinent. In the s o u t h e a s t e r n Arabian Sea the top of the thermocline is deepest between November and April (80-130m) and shallowest between J u l y a n d Sep- tember (10-30 m). During the s o u t h w e s t monsoon s e a s o n in a r e a s of strong upwelling activity, the thermocline r e a c h e s the very surface.

Considering the presence of a well defined s e a s o n a l thermocline which exhibits a periodic u p a n d down movement, t h e correlation of SST with o c c u r e n c e / a b u n d a n c e of pelagic fish Is possible within a r e a s o n a b l e limit.

Correlating SST with the o c c u r e n c e / a b u n d a n c e of demersal fish should be a t t e m p t e d with caution since many of the commercially Important demersal fish are known to be s t e n o t h e r m a l , not capable of tolerating wide variations in sea water t e m p e r a t u r e . They are also known to h a b l t a t e ecosystems below the seasonal thermocline.

(16)

Application of remote sensing techniques for locating pelagic fish Future p r o s p e c t s :

A. The MARSIS Centre of CMFRI is planning to c o n t i n u e t h e PFZ vali- dation programme by extending the activity to more fish landing centres along the Kerala coast d u r i n g the next PFZ forecast season commencing from No- vember 1996 to obtain confirmatory evidence on observations made above.

A r r a n g e m e n t s are also made for the collection of s e a t r u t h d a t a in the area u n d e r study during pre-monsoon, southwest monsoon and post-monsoon sea- s o n s .

B. The centre also proposes to evolve a prediction system for Skipjack t u n a { Katsuwonus pelamis) Fishery In the Lakshadweep Islands b a s e d on PFZ forecasts b r o u g h t out by NRSA by organising a regular feedback from the a c t i v e f i s h e r m e n of t h e i s l a n d s t h r o u g h t h e D i r e c t o r a t e of F i s h e r i e s , Lakshadweep. Skipjack t u n a fishery, being pelagic in n a t u r e , mainly em- ploying a single fishing methodology, viz., t u n a pole and line fishing, is ex- pected to give b e t t e r correlation with PFZ forecasts generated out of SST Imageries. Moreover, the fishing activity is aimed at harvesting a single spe- cies Katsuwonus pelamis.

C. In due course, t h r o u g h the 1RS-P3 a n d P4 satellites it would be- come possible to obtain chlorophyll distribution a t sea surface which in t u r n can be correlated with the occurence / a b u n d a n c e of pelagic herbivores like oil s a r d i n e [Sardinella longiceps) in space a n d time along with SST d a t a . The MARSIS Centre of CMFRI is fully Involved in the above mentioned activities t h r o u g h close collaboration with Space Application Centre, A h m e d a b a d a n d National Remote Sensing Agency, Hyderabad.

Evolving a suitable prediction system for the commercially i m p o r t a n t pelagic fisheries In the coastal w a t e r s of t h e Indian s u b c o n t i n e n t a n d the island territories b a s e d on PFZ forecasts will greatly help the a r t i s a n a l a n d small mechanised sector fishermen to reduce the searching time for fish shoals and thereby effecting an overall reduction In the cost of fishing o p e r a t i o n s .

A c k n o w l e d g e m e n t s

The a u t h o r s t h a n k the Dept. of Ocean Development, Govt, of India for sponsoring the project titled "MARSIS" and the National Remote Sensing Agency (NRSA) for co-ordinating the programme at our centre. We also t h a n k Dr.

1[93~

(17)

Marine Fisheries Research and Management

M . D e v r a J , D i r e c t o r , In u n d e r t a k i n g t h e a b o v e m e n t i o n e d s t u d y . R e f e r e n c e s

Fiuza. A.F.G., 1990. Application of satellite remote sensing to fisheries. In : Operations Research and Management In Fishing, Kluwer Academic Publishers.

Laurs, R.M. Fiedler, P.C. and Montgomery, D.R., 1984. Albacore t u n a catch distribu- tion relative to environmental features observed from s a t e l h t e s . Deep SeaRes.. 31 : 1085-1099.

Petterson, L.H., 1992. Application of Remote Sensing to Fisheries, Final Project Report to the JRC at Ispra, Nansen Research Centre.

S a n t o s , A.M.P., and Fiuza, A.F.G., 1992. Supporting the Portuguese Fisheries with satellites. Symposium of the International Space Year. Munich, Germany Sloggett, D.R., Aiken, J, Srokosz, M.. and Boxall,S., 1995. Operational u s e s of ocean

colour data-Perspectives for t h e OCTOPUS Programme, PP : 2 8 9 - 3 0 3 , In : Sensors and Environmental Applications of Remote Sensing. Asken, J . (ed), 1995, Balkema / Rotterdam / Brookfield / 1995.-

Squire, J.L.. 1982. Catch t e m p e r a t u r e s for some Important marine species off Califor- nia, NCAA Tech.Rep.. NMFS-SSRF-759 : 1-19.

References

Related documents

The agencies involved in the validation exercise include the National Remote Sensing Agency, Space Application Centre, Central Marine Fisheries Research Institute, Fishery Survey

(a) Positive relationShip between PFZ resulting out of comparatively high gradients of SST (2C and above) and fishable concentrations of commercially important

Itensive validation programme of Potential Fishing Zone (PFZ) advisories carried ut by the Central Marine Fisheries Research Institute around Minicoy island re- ealed

Secondary data on fish production, exports and strength of fishing fleet were collected from Central Marine Fisheries Research Institute (CMFRI), Marine Products Export

© 1998, Central Marine Fisheries Research Institute, Cochin -14 Printed at PAICO,

© 1998, Central Marine Fisheries Research Institute, Cochin -14 Printed at PAICO,

The Institute with its Headquarters at Cochin and Research and Field centres all along the Indian coast line, conducts mission-oriented researches in important areas of marine

The Institute with its Headquarters at Cochin and Research and Field centres all along the Indian coast line, conducts mission-oriented researches on important areas of marine