Fishery, population dynamics and stock assessment of the spotted seer in gill net fishery at Veraval

The fishery and population characteristics of Scomberomorus guttatus (Bloch & Schneider) from Veraval was studied for the period 2003 – 2006. The average annual catch was 378 t, forming 14.4% of the total gill net catches at Veraval. The postmonsoon and winter seasons (September to January) were the most productive seasons in terms of catch and catch rate. The length–weight relationship showed that growth was isometric for the species. The von Bertalanffy growth equation was: Lt = 61.27 [1 – e - 1.4 (t + 0.0046)] and length attained at the end of 1 and 2 years were 46.3 cm and 57.6 cm respectively. The growth performance index was 3.721 and longevity was 2.138 years. Recruitment pattern was unimodal with peak recruitment from February - July and the length at first capture was 21.1 cm. The natural mortality, fishing mortality and total mortality were 1.79, 2.92 and 4.71, respectively and exploitation ratio was 0.62. The maximum sustainable yield was 305 t, which was lower than the average annual catch indicating over-exploitation of the species. The yield per recruit and biomass per recruit was 198.9 g and 66.9 g respectively. An increase in relative yield to 101.8% would be obtained by decreasing the present level of fishing by 20%

Fishery and population dynamics of Harpadon nehereus (Ham.) off the Saurashtra coast

The fishery and population dynamics of Bombay duck (Harpadon nehereus Ham.) from Nawabunder, Rajpara and Jaffrabad were studied for the period from 2003 to 2006. The average annual landings of Harpadon nehereus was 25,079 t, which contributed 31.12 % to the total dol net catches. The seasonal peak in catch was recorded during September – January and in May. The length–weight relationship showed that growth was isometric and there was no significant variation between the sexes. The overall sex ratio was 1:0.99 with gravid and ripe females encountered in most months with a peak during September – December. The length at first maturity of female was 20.2 cm. The growth parameters were estimated as L = 35.39 cm and K = 0.86 and the length attained at the end of 1, 2 and 3 years were 20.66 cm, 29.16 cm and 32.75 cm respectively. The length at first capture was 3.42 cm with recruitment occurring in most months of the year with a peak during February – June. The natural mortality, fishing mortality and total mortality were 1.52, 1.73 and 3.25 respectively and the exploitation ratio was 0.53. The maximum sustainable yield was 23,557 t, which was lower than the average annual catch indicating overexploitation of the species. The yield per recruit and biomass per recruit was 6.565 g and 3.79 g and increase in relative yield by 111.45 % would be obtained by decreasing the present level of fishing by 40 %

Record landings of cephalopods by trawlers at Veraval during first quarter of 2009

Cephalopods represent one of the most important exploited marine fishery resources at Veraval. The cephalopod landings in Gujarat increased by more than two folds from 0.234 lakh t in 2002 to 0.49 lakh t in 2006 (Mohanraj et al., 2009), with a concomitant increase in catch rate from 5.05 kg h-1 in 2003 to 14.74 kg h-1 in 2006. The cephalopod resource was constituted mainly by Loligo duvauceli, Sepia pharaonis and S. aculeat

By-catch of the gastropod Tibia spp. in gillnets operated along Gujarat coast

The rocky coastal belt of Gujarat possesses an enormous potential resource of lobsters. Gillnets are regularly operated for lobster along the coast of Mangrol, Porbunder and Muldwarka. Gastropods such as Tibia maculata and Tibia curta occurred in large quantities as by-catch along with lobsters. Other gastropods such as Archipecten sp. and Murex sp. also make their occurrence in small quantities

Industrial fisheries off Saurashtra coast based on exploratory survey during 1985-'88

In Saurashtra waters, where fishery resource is currently being well exploited by private sector, exploratory survey programmes are being conducted by Government of India. The analysis, based on 4 year survey (1985-'88), with a view to provide information and to extend our knowledge about the spatial and seasonal distribution of various industrially important fishes along the Saurashtra coast. Ribbon fish and sciaenids which constituted the bulk of the catch together formed more than 60% of the total catch and catch rate were 14.7 and 14.5 kg/hr respectively. Area-wise analysis of data revealed that maximum effort was expended in 21° 69 0 and the effort was very low in 21° 70° and 23° 68° Depth wise analysis revealed that the maximum catch rate of ribbon fish and other sciaenids was obtained at 21-30 m depth. The catch rate of elasmobranch, carangid and Lactarius lactarius was maximum at 41-50 m, cat fish, pomfret and perch at 51-60 m and carangid and cephalopod at 61-70 m depth

Flourishing trade of air bladders at Okha, Gujarat

The swim bladders of eels (Muraenesox talabonoides Bleeker), ghol (Protonibea diacanthus Lacepede) and koth (Otolithoides biauritus Cantor) are of best quality and fetch very high market price owing to the huge export demand. Fish air bladder is mainly used for making isinglass. Considerable quantity of eel, ghol and koth are landed at Okha by trawlers operating on the rocky bottom (18 m depth) off Jakhau. Around 500 trawlers having an overall length of 40 to 45 ft, powered with 80 - 105 HP engines are actively engaged in the fishing of eel, ghol and koth. The fishing trip lasts for 7 - 10 days with 4 - 6 hauls of 3 h duration per day depending on whether they fish during only day or both day and night. The trawlers carry on an average 10 to 12 nets having length of 35 - 40 m with cod end mesh size varying between 8 and 15 mm

Bumper catch of spiny lobsters by trawlers and gill netters at Okha, Gujarat

During the post-monsoon months of September and October in 2007, an estimated 900 t of spiny lobsters Panulirus polyphagus worth of Rs. 67 crores was landed by trawlers and gill netters at Okha and Rupenbander

Fishery and stock estimates of the silver pomfret, Pampus argenteus (Euphrasen), landed by gill netters at Veraval

The fishery and population characteristics of silver pomfret Pampus argenteus (Euphrasen) caught by gillnetters off Veraval were studied for the period from 2003 to 2007. The average annual landing of P. argenteus was 114.5 t, which contributed 4.5% to the total gill net catches. The period from July to September was the most productive in terms of catch and catch rate. The length–weight relationship showed that the growth was isometric. The sex ratio was 1.75 in favour of females. Mature females occurred throughout the year, with maximum during June – November. The length at first maturity of female was 27.5 cm. The von Bertalanffy growth equation was: Lt = 41.57 [1 – e - 0.64 (t + 0.0315)]. The length at first capture (Lc) was 8.2 cm with recruitment taking place throughout the year with two peaks during February-March and in August. The natural mortality (M), fishing mortality (F) and total mortality (Z) were 1.20, 2.11 and 3.31 respectively. The exploitation ratio (E) was 0.64. The Maximum Sustainable Yield (MSY: 90 t) was lower than the average annual catch indicating over-exploitation of the species. The yield per recruit (Y/R) and biomass per recruit (B/R) was 38.31 g and 18.16 g respectively. An increase in relative yield by 17.18% would be obtained by decreasing the present level of fishing by 60%

Record size landing of blackbanded trevally Seriolina nigrofasciata at Veraval

On the 4th of January 2008, two giant sized female blackbanded trevally Seriolina nigrofasciata Ruppell caught by hooks and line were landed at Bhidiya, Veraval (Fig. 1). This is the first report on the landing of black banded trevally at Veraval. The hooks hook no. 6) were suspended at a depth of 80 - 90 m from the trawler having overall length of 14 m and powered with 105 HP engine

Status of longtail tuna, Thunnus tonggol fishery along the Northwest coast of India

Longtail tuna, Thunnus tonggol, is a neritic species with continuous distribution along the continent of Asia from Iran to mainland China (Yesaki, 1993). The average landings during the 1995-2002 period along the Indian coast was about 5970 t of which 78% was contributed from the North-west region. Although the species has so far been reported to be exploited marginally only, since 1998 there has been a perceptible intensification of fishing activities mainly due to technological advancements all along the Indian coast and especially so along the North-west coast (Anon., 1996). Catches of T. tonggol which has shown an increasing trend along the North-west coast since the early 90s peaked during 2000 and subsequently showed a sudden decline with catches as low as when the fishery was just developing during 1990-92 period