Stake net Catch analysis of Ashtamudi Lake

Jyothilal C.S.<sup>1</sup>; Bennopereira F.G.<sup>2</sup>; Sumesh C.<sup>2</sup>; Sachin S.R.<sup>2</sup>; Binilshijith V.<sup>2</sup>

Stake net Catch analysis of Ashtamudi Lake

Jyothilal C.S.¹

, Bennopereira F.G.²

, Sumesh C.²

, Sachin S.R.²

, Binilshijith V.²

1. Department of Fisheries and Aquaculture, St. Alberts College, Ernakulam, Kerala, India
2. Department of Aquatic Biology and Fisheries, University of Kerala, India

Author

Correspondence author
International Journal of Aquaculture, 2015, Vol. 5, No. 14 doi: 10.5376/ija.2015.05.0014
Received: 21 Feb., 2015 Accepted: 03 Jun., 2015 Published: 16 Jun., 2015

This is an open access article published under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Preferred citation for this article:

Jyothilal C.S., Bennopereira F.G., Sumesh C., Sachin S.R. and Binilshijith V., 2015, Stake net Catch analysis of Ashtamudi Lake, International Journal of Aquaculture, 5(14): 1-5 (doi: 10.5376/ija.2015.05.0014)

Abstract

A general account on the stake net catch of Ashtamudi Lake during 2009 November- 2010 October is given. Estuaries and back waters are the back bone of marine fishery resources as they serve as the nursery for many of the penaeid prawns and fishes. Stake nets are widely used in the back waters, estuaries and coastal areas and it plays an important role in the commercial exploitation of prawns and fishes. The present study was aimed to analyze the stake net catches, which operated along the Ashtamudi lake. Prawns were contributed over 60% of the total catch. Among them, Penaeid prawns was the major contributor (93%). Fishes contributed only 32% of the total catch followed by mollusks (1%). As prawns become the major contributor of this gear, this net can be considered, a typical Prawn Fishing gear.

Keywords

Stake net; Penaeid prawn; Lunar month; Ashtamudi Lake

The back water fishery resources of high magnitude and support a rich fishery. The fishery wealth is composed of several fish species crustaceans and mollusks inhabiting prominently to the marine habit. The Ashtamudi back water system in Kerala is the second largest of its kind in the state next to Cochin back waters. Ashtamudi wetland is famous for its hydrological functions, its biodiversity and its support for fishery with nearly sustaining a lively fishing industry. It is connected with sea through out the year. Sakthikulangara-Neendakara fishing harbours (08030’N, 76053.3’E) are situated at the mouth of the Ashtamudi backwaters and about 9 kms north of Kollam town.These are the most important fishing harbours along the south west coast of India. Neendakara was the head quarters of the Indo-Norwegian community project, which was established in 1953. Although extensive studies have been carried out for the past two decades on the recruitment and biology of prawns of latter environment, the Ashtamudi has virtually remained neglected all these years in spite of the fact that its adjacent coastal waters have emerged as the most productive grounds for prawns in the country (George et al 1980).

The stake nets are, a group of fixed bag nets classified as stow nets on stakes fall under the class of bag nets with fixed mouth (Brandt, 1984) while Nedelec (1982) and Hameed and Boopendranath (2000) grouped them under the class, traps. These conical bag nets are set in streams and tidal waters to filter out small fishes and prawns that are swept along its course. These nets with local modification are widely operated in different parts of the world for the exploitation of prawns and fish resources. The description of stake net and mode of operation were given by Menon and Raman (1961) and Kurian and Sebastian (1986). The design of the stake net in detail along with economics of stake nets operation in the back waters of Kerala were given by Hriidayanathan and Pauly (1993). Set bag nets (Behundi jal) of three types- Small, medium and large are widely used in Bangladesh (Vendeville, 1990). In Srilanka, stake seine nets fixed close to sea mouth are used extensively for catching shrimp that migrate from Negambo estuary to the sea (Amarasinghe et al., 1997). Stake nets known as Hadra nets are operated for fin fish within the tidal and sub tidal zones of the Kuwait coast (Al-Rashoud et al., 1994). The main objective of the present study was to analyse the catches of stake nets operated along the Ashtamudi lake.

Materials and Methods

The present study was carried out at Ashtamudi lake during a period from November 2009 to October 2010. Four groups of stake nets were selected within 2 kms from the barmouth of Ashtamudi lake. (North east arm, Southern arm and near the bar mouth of the lake). Monthly stake net sample collections were made on the basis of lunar phase owing to the ebb tide. Water current speed was found high during the Lunar phases . One kg random samples were collected from each groups. Samples from each group were collected during each full moon and new moon phase at every month. Live photographs of specimens were taken after each collection and specimens were preserved in common fixative, namely commercial formalin of 37-41 % strength.

Identification of shrimps were based on FAO identification manuals (Holothius, 1980; Fisher and Bianchi, 1984). Identification of fish fauna of stake net catch was done following

Day (1878), Munro (1955), Talwar and Jhingran (1991) and Fish base; (Froese and Pauly, 2007). The mollusk was identified with the help of standard keys (Pinn, 1990).

Results and Discussion

Among the total catch, crustacean contributed 67 %, fishes contributed 32 % and Molluscs recorded 1% of the total catch (Figure 1).

Figure 1 Ordervise catch compostion of fish catch

10 Orders of fishes

33 Families of fishes

48 Species

4 Families of crustaceans

12 species

4 families of Molluscs

5 species

Crustaceans

12 Species of crustaceans belonging to 4 families were identified from the study area. Penaeid prawns are the major groups landed by this gear. Among crustaceans family penaiedae contributed 93% of the catch followed by Sergestidae (4%), Portunidae (2%), Squillidae (1%) and Diogenidae. Among penaeid prawns Metapenaeus dobsonii (54%) and Metapenaeus affinis (33%) are the major contributors which is followed by Metapenaeus monoceros(7%), Penaeus merguensis (4%), Parapeanaeopsis stylifera (1%) and Penaeus indicus (1%). Major contributors of family portunidae were Charybdis cruciata (49%) followed by Scylla serrata (28%) and Portunus pelagicus (23%). Acetes indicus alone contributed to family sergestedae (4%). Orato squilla perpensa and Diogenes costatus contributed to the families Squillidae and Diogenidae respectively. Two peaks of crustacean catches were noted during the study; from March-May and September –November. M.dobsonii was the major species contributed during each peaks followed by M. affinis (Figure 2, 3).

Figure 2 Species composition of Family Penaeidae

Figure 3 Species composition of Family Portunidae

Molluscs

Molluscs contributed 1% of the total catch belonging to 5 families Veneridae, Corbiculidae, Loliginidae and Octopodidae were the families encountered during the present study

Family:Veneridae

Paphia malabarica

Family:Corbiculidae

Villorita cyprinoides

Family:Loliginidae

Loligo duvauceli

Family:Octopodidae

Octopus macropus

Cistopus sp

FISHES

Fishes contributed 32% of the total catch which was merely low when compared with total crustacean catch. 48 species of fishes were identified which belongs to 10 orders and 33 families.

48 genera/species of fishes belong to 10 orders contributed to the stake net catches during the study period. Among the orders,Tetradontiformes (15%) and Anguilliformes (13%). Perciformes was contributed by 24 fish species which is followed by Tetradontiformes (7 species) and Anguilliformes (6 species).

Two fishing periods of 6 to 8 days were noted in each lunar month. The present observation do agree with Nandakumar (2004) who recorded January-February as the peak season for the stake net for shrimps. The stake net fishery is mainly supported by three species, Metapenaeus dobsonii, M. affinis, M. monoceros and Penaeus indicus. Similar observations were made by Menon and Raman, (1961); George et al., (1974), (1998); and Thomas et al., (1999). During the period of the study, Metapenaeus dobsonii was found the dominant species. Similar observations were made by Menon and Raman, 1961; George 1961; Nandakumar, 2004 and Saly et al., 2007. The Prawn catch in stake nets showed significant variation in different months and two peaks in September-November and March-May were reported. The maximum catch of Metapenaeus dobsonii in September with two peaks, September-October and January-April, is due to two peak breeding season it has, One in June-August and onother in November-December (Saly et al., 2007). Similar observations were noted during this study period. During the study period, maximum catches of prawns were noticed on different days in the new and full moon phases and there was no relationship between catch rate and any particular day in the new moon or full moon. This result coincide with the findings of Nandakumar, (2004). He noted the peak season of penaeid shrimp fishery in Cochin back waters during January-May and the present study conducted at Ashtamudi lake showed similar trend.

During the pre-monsoon period Stolephorus indicus and Sardinella longiceps contributed major share. Stolephorus indicus registered an increase in catch from February (14%), March (39%) and April (40%) which may be associated with spawning migration and increased frequency of stake net operation during these months. Sardinella longiceps also showed similar trends in the catches and a peak of 40% were noticed during May. Monsoon and post monsoon months were dominated by species like Ambassis commersonii, Secutor insidiator, Leiognathus equulus and Tachysurus maculatus. Post monsoon months noticed a peak of catches of Anguilla bicolor, Anguilla bengalensis, Ariosoma anago, Uroconger lepturus and Gymnothorax undulatus. Tetradontiformes showed a marginal increase in catches during post monsoon months which includes Arothron hispidus, A.immaculatus, Lagocephalus inermis, Chelonodon patoca, Triacanthus biaculeatus and Pseudobalistes flavimarginatus which may be associated with the increased rate of rainfall. Perciformes marginally contributed to the stake net fishery which includes , Ambassis commersonii, Epinephalus diacanthus, Apogon quadrifasciatus, Lutjanus argentimaculatus, Chaetodon collare, Scatophagus argus, Heniochus acuminatus, Therapon jarbua, Gerres filamentosus, Etroplus suratensis, Etroplus maculatus, Siganus javus, Acanthurus nigrofuscus, Leiognathus bindus, Leiognathus equulus, Leiognathus daura, Secutor insidiator, Liza parzia, Trichiurus lepturus, Johnius oscius, Trypauchan vagina and Scarus ghobban (Figure 4).

Figure 4 Month vise catch composition of stake net

Monthly Rainfall data (mm)

YEAR	NOV	DEC
2009	258.9	7.9
	JAN	FEB	APR	MAY	JUN	JUL	AUG	SEP	OCT
2010	26.2	0.0	29.6	166.9	262.1	358.8	373.2	229.9	365.0

Low catch contribution of molluscs were noted through out the study period. The major taxa caught in the stake net were Loligo duvauceli, Cistopus sp, Octopus macropus, Paphia malabarica and Villorita cyprinoides.

As demand for prawns in the international market increased, the easy profit from stake nets attracted the peoples including non fishermen. Substantial increase in the number of stake nets and the use of very small meshes in the codend resulted in the trapping of immature prawns, which affects the sustainability of prawn fisheries. The present study also reveals the high frequency of the stake nets in the study area, probably to exploit the prawn fish resources, which fetch an exorbitant price both in international and domestic market. As indicated by earlier workers, small mesh size of the code end of the stake nets calls for some urgent interventions. The concept of infinite fishery resources has already been challenged due to various anthropogenic reasons. The present study also warrants for judicious harvesting of the resources.

References

Al-Rashoud A.K., Siddiqui M.S., Jamal A.H., and Mittu K.T., 1994, Conservation and Management of Coastal Fishery resources of Kuwait, Coastal Zone Canada 1994, Co operation in the Coastal Zone, Conference Proceedings,Vol. 1: 360-374

Amarasinghe U.S., Chandrasekara W.U., and Kithsiri H.M.P., 1997, Traditional Practices for resource sharing in an artisanal fishery of a Sri Lankan estuary, Asian Fish. Sci., 9(4): 311-323

Brandt A.V., 1984, Fish Catching Methods of the World (3^rd Edn.), Fishing News Books Ltd., London, 432 p

Day F., 1878, The Fishes of India: Being a Natural History of Fishes Known to Inhabit the Seas and Freshwaters of India, Burma and Ceylon, Today and Tomorrows Book Agency, New Delhi

Fischer W., and Bianchi G., 1984, FAO Species Identification Sheets for Fishery Purposes, Western Indian Ocean (Fishing Area 51), FAO, Rome

Froese R., and Pauly D., (Eds.), 2007, Fish Base, World Wide Web electronic publication, www.fishbase.org,version (09/2007)

George M.J., Suseelan C., Thomas M.M., and Kurup N.S., 1980, A case of over-fishing: Depletion of shrimp resources along Neendakara coast, Kerala, Mar. Fish. Infor. Serv. T & E Ser., 18: 1-8

George V.C., Nayar S.R., and Iyer H.K., 1974, Mesh regulation in backwater prawn fishing gear, Fish. Techol., 9 (2): 117-128

George V.C., Vijayan V., Mathai P.G., Varghese M.D., and Iyer H.K., 1998, Influence of lunar periodicity on the size composition and abundance of penaeid prawns in stake nets, Fish. Technol., 35 (2): 67-72

Hameed M.S., and Boopendranath M.R., 2000, Modern Fishing Gear Technology, Daya publishing House, Delhi, 186p

Holthius L.B., 1980, Shrimps and Prawns of the World, FAO Species Catelogue, Vol.1. F.A.O., Rome

Hridayanathan C., and Pauly K.V., 1993, Stake nets of Kerala- their present condition and future prospects, Proc. National Workshop on Low Energy Fishing, 8-9 August, 1991, Fishery Technology (Special Issue), 229-233

Kurian C.V., and Sebastian V.O., 1986, Prawn and Prawn Fisheries of India, Hindustan Publishing Corporation (India) Ltd., Delhi: 280pp

Menon M.K., and Raman K., 1961, Observations on the shrimp fishery of the Cochin backwaters with special reference to the stake net catches, Indian J. Fish., 8(1): 1-23

Manro I.S.R., 1955, Marine and Freshwater Fishes of Ceylon, Dept. of External Affairs, Canberra, 349pp

Nandakumar G., 2004, Shrimp fishery by stake nets in Cochin barmouth area with special reference to Metapenaeus monoceros (Fabricius), Indian J. Fish., 51(4): 431-439

Nedelec C., 1982, Defenition and Classification of Fishing Gear Categories, FAO Fish, Tech. Pap., 222: 51p

Pinn F., 1990, Sea Snails of Pondicherry,Nehru Science Centre, Pondicherry, 215 pp

Talwar P.K., and Kacker R.K., 1984, Commercial Sea Fishes of India, Zoological Survey of India, Calcutta, 997 pp

Thomas S.N., Edwin L., George V.C., and Iyer H.K., 1999, Size composition and abundance of penaeid shrimps in stake nets with reference to lunar phase, Proc. 4^th Indian Fisheries Forum, 24-28 Nov. 1996, Kochi: 463-466

Vendeville P., 1990, Tropical Shrimp Fisheries: Types of Fishing Gear used and their selectivity, FAO Fish. Tech. Paper, 261:75 p

George M.J., 1961, Studies on the prawn fishery of Cochin and Alleppey coast, Indian Journal of Fisheries, 8(1): 75-95

Thomas S.N., Edwin L., and Meenakumari B., 2007, Stake nets of Kerala, Central Institute of Fisheries Technology, CIFT golden jubilee Series, Cochin, 35 pp

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