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Marine biogrowth infestation of a seawater intake system was investigated. A digital camera fixed onto a skid was used to record the biogrowth at intervals of 5 m up to a depth of 55 m. Divers inspected the intake shaft and collected the biogrowth samples for biomass estimation. A biomass density of 7.5 kg m-2 and 28.2 kg m-2 was recorded at 5 and 30 m depths respectively. Inspection by the divers revealed that hard-shelled organisms such as oysters and brown and green mussels were observed in plenty up to a thickness of 15 cm and bryozoans grew as epibionts. At lower depths (

Objectives: The main objective of the study was to collect and rear the unmarketable, small sized S.javus which is mostly rejected by the traditional fisherman. During fishing activities, under sized S.javus ranging in sizes from 25 to 40 kg (< 30-40 % of total catch/day) is being captured. Due to very low marketable value these small fishes (

Sea farm cages attract a range of wild fish species by providing shelter and food. The fish aggregation study was carried out around the open sea cages deployed at (9°20′03.95″N; 79°19′53.05″E) Olaikuda, Rameshwaram. A total of 2515 fish representing 51 species from 26 families and 9 orders were recorded by Underwater Visual Census (UVC) method from both sea-cage farm and control site. The genus Siganus was very common in both the cage and the control site and recorded in each sampling. The fish abundance distribution depicted a similar pattern to that of the cluster analysis when subjected to 2D NMDS ordinations and showed a distinct cluster pattern for the cage site. The Shannon Wiener diversity indices illustrated high abundance (224) and richness (7.33) at the cage site compared to the control site (common fishing ground). There was a significant temporal variation (F = 8.9, p

The use of functional information of taxa is a promising approach to uncover the underlying mechanism of ecosystem functioning. We used biological trait analysis (BTA) to assess the functional response of subtidal macrobenthos with multiple stressors. Seventeen environmental variables from 42 stations of five coastal districts were assessed along the southeast coast of India. Dominant fauna was assigned into 20 categories belonging to six functional traits. Additionally, we used five ecological groups (EG) of AMBI as a covariable trait to validate functional traits and EG relationship. The trait composition in the communities showed significant variation between undisturbed and disturbed areas. RLQ/Fourth corner combined approach illustrated the effects of stressors and isolated the corresponding species associated with different stressors. Smaller, short-lived, deposit-feeding, and discretely motile fauna occurred at the disturbed areas, whereas, larger, long-lived, and highly motile at the undisturbed area. Dissolved oxygen, organic enrichment, and metals concentration were the main environmental descriptors influencing the trait composition. The results highlight the importance of the BTA approach to uncover the response of the macrobenthic community to anthropogenic disturbances-driven impacts in multi-stressed near-shore coastal ecosystems.

Coastal brackishwater resources are highly fertile, rich in biodiversity and provide livelihood to traditional fisher families. However, due to natural disturbances and manmade interruptions, its fishery resources are depleted, hence, the livelihoods of dependent fishers are threatened. Aquaculture of fishes in customized cages and pens is a proficient approach for the efficient utilization of this productive natural resource. In this context, a three-tier cage farming system of Asian Seabass fish (Lates calcarifer) comprised of a nursery, pre-grow out and grow-out phases was developed and validated for its techno-economic viability with the participation of fisher folk. The technical indicators viz., fish survival, feed conversion, growth rate, productivity, economic parameters viz., Benefit Cost Ratio, Pay-back period and Internal Rate of Return and the livelihood security pointers have substantially shown that the system is technically feasible, economically viable, socially acceptable and hence, sustainable. Planned interventions in the form of appropriate policy guidelines to undertake community involved cage aquaculture in the coastal brackishwaters, a scheme for periodical flushing of bar mouths to ensure connectivity with the sea, institutional credit and insurance support are outlined to up-scale the adoption of cage farming technology in the brackishwaters across the coastal states of India. It is a win-win approach for the efficient utilization of coastal brackishwaters for augmenting fish production and enhancing the livelihood security of coastal fishers.

Coastal mariculture is now facing tremendous pressures, especially from the anthropogenic activities, variable environment, and multi-user conflict. Hence, offshore mariculture is envisioned to enhance the production by promoting the commercial farming (floating cages) of cobia (Rachycentron canadum) and other fin fishes. Essential environmental parameters for mariculture have been selected and converted into thematic layers using Geographical Information System (GIS) tool. Weights of relative importance were assigned to each layer and integrated together through overlay analysis to provide a final model suggesting possible offshore floating marine fish cage deployment sites. In the present study, it is estimated that from 368,009 km2 area within 100 m depth of Indian Exclusive Economic Zone available for mariculture activities, about 161,188 km2 area is appropriate for deploying cages. There are 76,396 km2 of highly suitable and approximately 84,792 km2 of suitable areas available for mariculture in India including Andaman & Nicobar and Lakshadweep Islands. Analysis of variance (ANOVA-one way) showed significant (p

Precopulatory mate guarding is a characteristic feature in the mating behaviour of many Malacostraca, and a necessary prerequisite for those species in which female receptivity for males is restricted to a short period of time after the pubertal/reproductive moult. This study deals with the pre-mate guarding behaviour of the semi-terrestrial isopod Ligia dentipes living in the crevices of coral boulders and rocks in the supralittoral region of the Andaman Islands. As in other isopods, moulting in L. dentipes is biphasic, in which the posterior body part invariably moults first. The guarding male aids the female partner in the removal of the moulted exoskeleton. Mating occurs immediately after the posterior body exuviates. The male leaves the female after copulation and goes in search of another receptive female, demonstrating a polygamous mating system in these isopods. The mated females also re-mate with several other males without mate guarding. Females that had mated several times produced more young, ...

Captive broodstock of the spiny lobster, Panulirus homarus, mated successfully and produced more than 105 spawnings over 4 years. Improvements in nutrition and rearing conditions increased the number of spawnings from less than 2, to 4 per year. A single breeder mates three or more times in a year and may spawn more than once following a single mating. An average of four repetitive spawnings per year was recorded. One third of the females spawned 5 times and a single female spawned 7 times in one year. The phyllosoma were released in one or two batches on successive days. The number of phyllosoma larvae released varied from 16 000 to 529 180 with breeder weights ranging from 218 to 696 g.

A pair of subadult Panulirus ornatus was reared in the laboratory from July 2001. The female grew from 0.6 to 1.3 kg and the male from 0.5 to 1.6 kg in 2 years before the first mating in July 2003. In 6 months, from July to December 2003, the pair mated and spawned 3 times, producing 1.6 million eggs and 1.1 million phyllosoma larvae. Mating occurred 25 and 63 days after moulting. The female spawned 2–3 days after mating and the incubation time ranged from 23 to 27 days. The phyllosoma larvae were released over 2 successive days. The growth rate reduced after first mating in both the male and female and the female expended 42% of the total weight gain for egg production.

Coral cover, live-form categories, bleaching and their recovery were monitored in North Bay, South Andaman during pre- and post-tsunami periods. The reef is a fringing type, with a total coral cover of 313,382 m2. The total live and dead coral percentages recorded prior to tsunami were 29.4% and 27%, respectively. A patchy bleaching of 7.5% was recorded in month of April–May 2005. However, the coral reef started to recover quickly, and as much as 4.7% of recovery was recorded, and 2.8% of the bleached coral failed to recover. No significant variations in the physicochemical parameters were recorded prior to and post-tsunami. A sudden change in the water column height due the land subduction caused by the mega earthquake on 26 December 2004 was evident. The sudden change in depth and light penetration might have exerted a stress in the corals, leading to expulsion of zooxanthellae from the gastrodermal layer of cells, causing the bleaching phenomena.