Results of the Austrian-Ceylonese hydrobiological mission 1970 of the 1st Zoological Institute University of Vienna (Austria) and the Department of Zoology of the University of Ceylon, Vidyalankara Campus, Kelaniya (Sri Lanka). Pt 17. The freshwater gastropods of Ceylon

In the present study the specimens collected by the Austrian-Ceylones hydrobiological mission 1970 are described. The freshwater gastropods in this study were collected from 100 different localities, mostly running waters, but some were also collected from stagnant waters like pools, irrigated paddy fields, swamps and water reservoirs (tanks). Listed from these localities are 31 species (and subspecies) 28 species are Streptoneura (=Prosobranchia), 3 species are Euthyneura-Pulmonata Basommatophora.

Modification to the bilge and sea water pumps fitted in 17.5 metre Jingha type trawlers

This paper brings out the difficulties encountered with the Bilge and sea water circulating pumps which are fitted and drawn in series along with a fresh water pump in the 17.5 m fishing trawlers.

Proximate composition of 17 species of Indian fish

Miscellaneous fish from the catches of shrimp trawlers constitute a major portion of the marine fish catch in India, its quantity in annual landing being of the order of 50,000 tons. At present it is often not brought to the shore since it fetches only very low price. It consists of several species and is a cheap source of animal protein. Attempts are made in India in various centres (Anon. 1972-73) to utilise them effectively by formulating various speciality products acceptable to consumers.

Import substitution of combination wire rope. Part 2. Production and standardisation of 17 mm dia combination wire rope.

The prototype combination wire rope (Cift-CWR 1) developed for deep sea trawling was further studied for improvement, optimisation of efficiency and standardization. A series of improved prototype combination wire ropes (Cift-CWR 2 to 6) were twisted and evaluated their mechanical properties and reported in this paper with recommendations for a standard 17mm dia combination wire rope of 6S (7C+8+1 Scr) + 6 Crs(6+1+1 Crc) construction.

Report on BOBLME Indian mackerel genetic data analysis including final workshop, Phuket, Thailand, 17-19 February 2015

This workshop followed on from two previous workshops held in Colombo, Sri Lanka, 2012 and Kochi, India in 2013. The 14 microsattellite markers had previously been developed for Indian Mackerel (Rastrelliger kanagurta) were used on 31 tissue collections from all eight countries were genotyped in India.

Meeting on BOBLME engagement in the International Indian Ocean Expedition 50th anniversary initiative (IIOE-2), Bangkok, Thailand, 17-18 March, 2015

Objectives included; a contribution to understanding large-scale processes affecting the Bay of Bengal Large Marine Ecosystem Project (BOBLME) and it's living resources; and to align with International Indian Ocean Expedition (IIOE-2) (2015-2020) which will extensively explore and study the Indian Ocean to improve understanding of the ocean and coupled climate processes.

Reproductive physiology of ribbon fish (Trichiurus lepturus)

The ribbon fishes ‘of the family Trichiuridac are represented as one of the most important food resources in Indian ocean. High density of the dominant species of ribbon fish (Trichiurus lepturus) in Oman sea and the 'Tillable catch in last yeas (more than 7000 tones per year) makes a trust area for studing their population biolog and stock assessment. As our knowledge on reproductive biology of this species has an important role on their fisheries management, as well as conservation of this stock from decline or over fishing, this research was held to determine some aspects of reproductive physiology of ribbon fish and the effects of environmental factors in gonadal cycle. The goals of the present thesis is to determine some aspects of reproductive physiology such as gonadosomatic index (GSI) , hepatosomatic index (HSI), condition factor (Ko, fecundity, sex ratio, size at first maturity, size at maturity (LM5O) and their relative hormonal & biochemical fluctuations. In this regards annual variation of sex hormones ic. estradiol 17-B, progestron, cortisol, testostrone and gonadotropins FSH (GTH-I) , LH (GTH-ll)I were measured ; gonadal histological studies were done by light & electron micrography. The research was carried out from April 1995 to January 19% in Ras Nleidani in the north part of Oman sea, and the environmental factors such as temperature, salinity, oxygen, rainfall and pH were measured. The effects of these parameters on reproductive cycle and hormonal fluctuationswere discussed by using correlation and principle component analysis (PCA). Female Ribbon fish reproductive strategy shows the same paterns of nonguarder marine teleosts. T. lepturus has more than one spawning season (existance of egges in different size in each month) and therfore it must have asynchronous ovaries and belong to continious spawners. GSI and HSI are good evidences for this type of reproductive patern. The testis of the lobular type , which is typical of most teleosts , is composed of numerous lobules which are separated from each other by a thin layer of fibrous connective tissue. GSI fluctuations revealed prolong- spawning time in males. There is significant increase in 17-13 estradiol. progestrone , cortisol and gonadotropins with maturity and prespawning period of female T lepturus. Plasma concentration of E2 and GTH II incresaed along with water temperature increasing (3300).. Spawning was observed from Nov. 1995 to Apr. 1996 in this species. Progestrone increased significantly with increasing rainfall in this season (P<0.01). Plasma cortisol levels increased with maturation and vitelpgenesis and also with the peak of spawning. From lenght-weight frequency and size distribution in each age groups and also minimum size at first maturity (52a cm) it would he concluded that T. lepturus must be matured at 2 years of age. Serum cholestrol and triglicerides significantly increased when maturation occured in this species. The relationship between alkaline phosphatase activity and hormonal fluctuations with maturity and vitelogenesis were discussed. Proximate compostion (muscle) shows significant variation with spawning period and maturity. Absolute individual fecundity (17420-159150) increased with body length and weight. Ultrastructural observations show dramatic variation in cell membrane (0ocyte membrane), yolk vesicles and, nucleolus dispersal in relation to maturity stages. fluctuations of gonadal hormones were discused in relation with vitelogenesis. Testosterone increased in males from Nov: to Mar. due to environmental impacts and spawning time. Sex ratio in different depth (10-40 m ,80-110 m) shows significnt differences in this ratio for two depths. In 10-40 m depth female shows dominant abundance to male in each months that may be due to their reproductive migration behaviour. The effects of temperature photoperiod and rainfall to maturity and spawning were discussed. According to -pawning period of T. leptunts in our sampling area it could be suggested that ribbon fish fi,theries must be restricted in the peak of spawning seasons (Feb. to Mar.) and in the spawning grounds (under 40 m depths). Other suggestions for population conservation have been mentioned.