Progress report on fish counting on the Rivers Itchen and Test

This progress report summarises work on NSHEB Mark 10 fish counters which are installed at Woodmill on the River Itchen and Nurseling Mill and Connegar Bridge on the River Test. Counters are evaluated and salmon behaviour regarding the counters examined. The report includes a a list of equipment needed for the efficient running of the project in the future.

Biological survey of the River Teign and tributaries, with reference to the effect of ball clay discharges

This is the Biological survey of the River Teign and tributaries, with reference to the effect of ball clay discharges report produced by South West Water Authority in 1979. A survey of the macroinvertebrate riffle fauna in the Ball Clay mining area of the Bovey Basin, following a period of low rainfall, indicated that the River Bovey and the River Teign between Chudleigh and Teign Bridge, Newton Abbot were of good quality. Further downstream, the R. Teign and the lower reaches of the Ugbrooke Stream were identified as being of doubtful quality with the discharge from ECC Broadway continuing to give cause for concern.

Cast-net fishery on northern portion of Lake Victoria and upper Victoria Nile

This project survey on cost-net was conducted at the Northern portion of Lake Victoria and Upper Victoria Nile. The selected fish -Landing sites, where sampling exercises were carried out include: Loco, Jinja pier (covering Lake Victoria) and Railway bridge, New bridge and Kalange (covering upper Victoria Nile). Research was focused on the cast-net design, target commercial fish stocks, impact of cast-net on the fish stocks, mesh-size and techniques ofcast-netting. The research results show that cast-net fishery destroys fish breeding and nursery grounds and other fish ecosystem. The gear targets Oreochromis niloticus and Occassional by catches e.g. Lates niloticus, Mormyrus Kannume Bagrus docmak and Clarias gariepinus. The multi-panel cast-net of mesh-sizes ranging from i (5lmm) to 6' (152mm) were adaptable by fishermen but they mostly caught immature fish. Nevertheless, this gear showed highest efficiency compared to other gears used at the project area. These research results will be useful to researchers, extension workers and Fishenes, students under taking special research or study on this gear.

An analysis of the experimental pole and line fishery conducted around Sri Lanka by Nichiro Fishing Company of Japan

Under a joint agreement the Government of Sri Lanka and the Nichiro Fishing Company of Japan have undertaken an experimental pole and line fishery around Sri Lanka with a view to determining the feasibility of establishing a joint commercial venture. 3 Japanese vessels conducted trials during the period March 1973-October 1974. Details of the vessels and cruises are given. A variety of fish were tried as bait, and the selection of appropriate bait is discussed. Catches and catch and effort statistics are presented, with tables showing distribution of the tuna. The results of the trials were below expectations, and are in part attributed to bait availability, and unfavorable weather conditions. Seasonal variation of the type of fishery is suggested in order to take account of this, and it is concluded that a fishery based on 45/50 ft combined pole and line and drift net fishing vessels might prove feasible.

Grouper, mudcrab and company

The paper discusses aquaculture practices on the three other high-value commodities which can be cultured as an alternative to shrimp. These species are grouper, mud crab and sea bass, it also discusses milkfish aquaculture practices.