Respiratory distress and Behavioural Anomalies of Indian major carp, Labeo rohita (Hamilton) Exposed to Sodium Cyanide

Sodium cyanide, is highly contaminating aquatic ecosystems as a toxic pollutant, was investigated in the present study for acute toxicity on freshwater fish Labeo rohita. The toxicity tests were conducted by static renewal bioassay method on the juveniles of fish was evaluated. The LC50 value of sodium cyanide to Labeo rohita was found out to be 320 µg/L. One third (106 µg/L) and one fifth (64 µg/L) of the LC50 value was selected for sublethal studies. Behavioural patterns and oxygen consumption were observed in both (1/3rd and 1/5th) sublethal concentrations (1, 5, 10 and 15 days). Sodium cyanide is highly toxic to the animal tested. Fish behaved irregular, erratic, and dartic movements, by followed hyperexcitability, loss of balance, finally settled to the bottom of the test chamber. A decrease in oxygen consumption was observed in 1/3rd (11.62% and -4.52%) and 1/5th (9.11% and -2.82%) sublethal concentrations. Fish under sublethal concentration were found to be under stress but not fatal

Impact of copper cyanide on the key metabolic enzymes of freshwater fish Catla catla (Hamilton)

Short term toxicity experiments were conducted to study the effect of metal cyanide complex (copper cyanide) on the key metabolic enzymes viz., lactate dehydrogenase (LDH), succinate dehydrogenase (SDH), glucose-6 phosphate dehydrogenase (G6PDH), aspartate amino transferase (AST) alanine amino transferase (ALT), acid phosphatase (AcP) and alkaline phosphatase (ALP) activity in Catla catla juveniles. A total of 60 fingerlings were (2±0.5 cm; 1.5±0.2 g) exposed to two sublethal concentrations (0.253 and 0.152 mg/L) for a period of 15 days. Copper cyanide had significant (P> 0.05) effect on the key metabolic enzymes, the highest activities were observed in the group exposed to 0.253 mg/L. Results suggest that metal cyanide complex significantly altered enzyme activities of fish in both the sublethal concentrations

Stranding of spinner dolphin, Stenella longirostris (Gray, 1828) at Karwar, Karnataka

A spinner dolphin, Stenella longirostris , locally called ‘handi meenu’ was noticed in dead condition floating near the marine cage farm of CMFRI, Karwar, approximately 600 m away, from sea shore of Aligadda village in the evening hours on 31st August 2012. The specimen was an adult female of 175 cm total length and 55 kg weight. The animal had a small injury near its left eye probably as a result of getting entangled in fishing nets or got injured in purse-seine operation which resulted in its death

Incidence of whale strandings in Uttara Kannada, Karnataka

Two instances of the whale strandings were observed in the Uttar Kannada district of Karnataka recently. The first one occurred on 06.05.2017 at Mungodlu, Kumta and the second at Karwar on 18.02.2018. The whale stranded at Mungodlu, near Vannalli village of Kumta Taluk, Uttara Kannada district, Karnataka (14° 26' 034" N and 74° 23' 005" E) was washed ashore in highly decayed condition with its dorsal portion upside down and species could not be identified. The total length of the whale was approximately 9 metres. The vertebrae were found exposed in the beach and a few numbers were collected and preserved in the museum of Karwar Research Centre of ICAR- CMFR

Note on the ocean sunfish, Mola mola (Linnaeus, 1758) landed at Karwar, west coast of India

The spine tail devil ray Mobula japanica (Muller & Henle, 1841) is a large zooplanktivorous ray circumglobally distributed within tropical to warm temperate waters. This species belong to the family Mobulidae. In the genus Mobula, the mouth is located ventrally and is currently represented by nine recognised species

Cobia culture in low volume cages in coastal waters of Uttara Kannada, Karnataka

Cobia, Rachycentron canadum is a marine finfish globally favoured for aquaculture. In India, cage culture of cobia was first reported by ICAR-CMFRI in 2013 with better growth rate recorded under conditions of higher salinities (Philipose et al.2013). The present report is on the growth and production of cobia, Rachycentron canadum in Gangavali estuary (14o 61’ 225’’ N and 74 o35’726’’E) of coastal Karnataka during the period 2018-19

Foreign objects observed in the stomach of a cobia (Rachycentron canadum) reared in sea cage at Karwar

Revival of short neck clam Paphia malabarica Chemnitz, 1782 In Kali estuary, Karwar, Karnatak

Risso's dolphin Grampus griseus, (Cuvier, 1812) rescued off Aligadda Beach, Karwar, Karnataka

On 23rd August 2013, a Risso’s Dolphin was nearly stranded on the Aligadda beach, Karwar. The dolphin appeared to be under stress and it was coming towards the shore. On seeing the dolphin, the local fishermen dragged it into the deeper waters to rescue. This dolphin is locally known as “God’s fish”, and hence the rescue operation was carried out by the local fishermen

Observations on variations in physico-chemical water parameters of marine fish cage farm off Karwar

An investigation was undertaken to study the fluctuations in the water quality parameters in a marine fish cage culture site off Karwar during the period 2009-2011. Two stations viz., one from cage site (Station 1) and the other away from the cage site (Station 2) were selected for the study. Water samples were collected at weekly intervals. Temperature of Station 1 varied from 28.5 ± 0.89 oC to 32.5 ± 1.04 oC during the first crop of Asian seabass culture in 2009-10 and it ranged between 26.7 ± 0.83 to 32.5 ± 0.79 oC during the second crop of seabass culture in 2010- 11. The salinity was minimum during July 2010 and maximum in May 2010. There was no significant difference observed between the water quality parameters of the two stations (p>0.05). However, difference in salinity was significant between the two culture periods in Station 1 (p<0.05). No significant difference was observed in the nutrient levels of the cage and reference sites and also between the two crops. No significant difference was observed between the mean weight of the fish and temperature of both the sites and periods. A positive correlation was observed between the weight gain of fish and salinity of water at cage site

Marine cage farming of Asian seabass under participatory mode - A success story

Karwar Research Centre of ICAR-CMFRI in association with the Directorate of fisheries, Govt. of Goa identified Polem village ( 14° 54' 21.12" N ; 74° 04' 32.20" E) in south Goa for the cage culture demonstration under the proejct 'National Innovations on Climate Resilient Agriculture (NICRA)'. Awareness programmes were conducted for the fishermen communities in the village regarding the present status of marine fisheries resources of India and future prospects