Reproductive biology of carpenter seabream (Argyrozona argyrozona) (Pisces: Sparidae) in a marine protected area

The carpenter seabream (Argyrozona argyrozona) is an endemic South African sparid that comprises an important part of the handline fishery. A three-year study (1998−2000) into its reproductive biology within the Tsitsikamma National Park revealed that these fishes are serial spawning late gonochorists. The size at 50% maturity (L50) was estimated at 292 and 297 mm FL for both females and males, respectively. A likelihood ratio test revealed that there was no significant difference between male and female L50 (P>0.5). Both monthly gonadosomatic indices and macroscopically determined ovarian stages strongly indicate that A. argyrozona within the Tsitsikamma National Park spawn in the astral summer between November and April. The presence of postovulatory follicles (POFs) confirmed a six-month spawning season, and monthly proportions of early (0−6 hour old) POFs showed that spawning frequency was highest (once every 1−2 days) from December to March. Although spawning season was more highly correlated to photoperiod (r = 0.859) than temperature (r = −0.161), the daily proportion of spawning fish was strongly correlated (r= 0.93) to ambient temperature over the range 9−22oC. These results indicate that short-term upwelling events, a strong feature in the Tsitsikamma National Park during summer, may negatively affect carpenter fecundity. Both spawning frequency and duration (i.e., length of spawning season) increased with fish length. As a result of the allometric relationship between annual fecundity and fish mass a 3-kg fish was calculated to produce fivefold more eggs per kilogram of body weight than a fish of 1 kg. In addition to producing more eggs per unit of weight each year, larger fish also produce significantly larger eggs.

An Observed Entanglement of Lagenorhynchus obliquidens in the High Seas Driftnet Area in the North Pacific

In August, 1991, an entanglement event was observed in the High Seas Driftnet area in the North Pacific. This description of an entanglement of Lagenorhynchus obliquidens is the first such documented report of dolphins entangling while bowriding. One of the entangled dolphins was rescued from the driftnet.

The Driftnet Fishery in the Fort Pierce-Port Salerno Area off Southeast Florida

From May through September 1987, observations were made on 38 trips in the driftnet fishery off the Fort Pierce-Port Salerno area off southeast Florida. Of the number and weight of fish landed on observed trips, 91.6 percent consisted of king mackerel, Scomberomorus cavalla, the targeted species. Over 33 species of fishes were observed among the discarded by-catch. The most frequently occurring species in the discards was little tunny, Euthynnus alletteratus, which made up 67.0 percent by number of the discarded by-catch. Total landings for all commercial gear from Saint Lucie and Martin counties (the counties of the study area) increased 516,741 pounds from 1986 to 1987. In 1986, 55 percent of the catch was from handline and 45 percent from driftnet landings. In 1987, 78 percent was from driftnet and 22 percent from handline landings. A comparison of lengths from recreational and commercial landings showed recreationally caught fish to be, on the average, smaller. No marine mammals, birds, or turtles were entangled in the net on observed trips. Data on cost of nets. fuel, and supplies plus the distribution of earnings among the crew were obtained for five driftnet boats.

Technical efficiency in artisanal fisheries (AF) in Badagry local government area of Lagos State, Nigeria

This study examined the technical efficiency in artisanal fisheries in Lagos State of Nigeria. The study employed a two stage random sampling procedure for the selection of 120 respondents. The analytical techniques involved descriptive statistics and estimation of technical efficiency following maximum likelihood estimation (MLE) procedure available in FRONTIER 4.1. The MLE result of the stochastic frontier production function showed that hired labour, cost of repair and capital items are critical factors that influences productivity of artisanal fishermen with the coefficient of hired labour being highly elastic. This implies that employing more labour will significantly increase the catch in the study area. The predicted farm efficiency with an average value of 0.92 showed that there is a marginal potential of about 8 percent to increase the catch, hence the income of the fishermen. The study further examined the factors that influence productivity of fishermen in the study area. Year of education, mode of operation and frequency of fishing have important implication on the technical efficiency of fishermen in the study area.

Northern Area Fisheries Advisory Committee 5th January, 1981

This is the report from the Northern Area Fisheries Advisory Committee meeting, which was held on the 5th January, 1981. It covers information on the review of fisheries byelaws, netting off Flimby Beach and the review of a net limitation order which was due to expire. It also includes the report by the area fisheries officer on fisheries activities which comments on river conditions and fishing for salmon, sea trout and brown trout, and the recorded numbers of fish which passed through Yearl Weir fish counter up to the 9th November. Also covered in the report is an update on Holmwrangle hatchery and the stocking numbers of salmon, sea trout and non migratory trout by the Water Authority. Finally the report adds about fish disease, biological work and the considerations of the River Caldew as a migratory fish river. The Fisheries Advisory Committee was part of the Regional Water Authorities, in this case the North West Water Authority. This preceded the Environment Agency which came into existence in 1996.

Central Area Fisheries Advisory Committee 8th January, 1981

This is the report from the Central Area Fisheries Advisory Committee meeting, which was held on the 8th January, 1981. It covers information on the review of fisheries byelaws, netting off Flimby beach, a large fish mortality in the River Calder and Ribble, and the review of a net limitation order which was due to expire. It also includes the stocking of Worthington Lakes, Rivington Group Reservoirs and the River Wyre, the update on the proposals for the development of angling at Stocks Reservoir and the report by the area fisheries officer on fisheries activities. This comments on river conditions and fishing for salmon, sea trout and brown trout, and migratory fish movement. Also covered in the report is an update on Middleton Hatchery, salmon cages in the River Leven, Langcliffe Hatchery and the pilot hatchery, and stocking numbers of coarse fish and non migratory trout by the Angling Associations. Finally the report adds about fish mortalities, fish disease, poaching and management work. The Fisheries Advisory Committee was part of the Regional Water Authorities, in this case the North West Water Authority. This preceded the Environment Agency which came into existence in 1996.

Southern Area Fisheries Advisory Committee 14th January, 1981

This is the report from the Southern Area Fisheries Advisory Committee meeting, which was held on the 14th January, 1981. It covers information on the review of fisheries byelaws and the proposal of having a separate coarse fish licences. It also includes the report by the area fisheries officer on fisheries activities. This comments on river conditions and fishing and an update on Hollingworth and Pilot hatchery. Finally the report adds about fish mortalities, and lists of stockings carried out for non migratory trout and coarse fish by the North West Water Authority and Angling Associations which gives the size of the fish, the source from which they came from and the receiving water. The Fisheries Advisory Committee was part of the Regional Water Authorities, in this case the North West Water Authority. This preceded the Environment Agency which came into existence in 1996.

Northern Area Fisheries Advisory Committee 30th March, 1981

This is the report from the Northern Area Fisheries Advisory Committee meeting, which was held on the 30th March, 1981. It covers the report by the area fisheries officer on fisheries activities. This comments on river conditions and fishing for salmon and coarse fish, migratory fish movements, and an update on Holmwrangle hatchery. Finally the report adds about stockings by the Angling Associations, and the monthy catches of salmon and sea trout for the 1980 season. The Fisheries Advisory Committee was part of the Regional Water Authorities, in this case the North West Water Authority. This preceded the Environment Agency which came into existence in 1996.

Central Area Fisheries Advisory Committee 1st April, 1981

This is the report from the Central Area Fisheries Advisory Committee meeting, which was held on the 1st April, 1981. It covers information on Rivers Leven and Kent fish distribution and water quality surveys 1980, authority works on Headwater Beck of the River Hodder and the River Douglas, the annual report on match fishing at Skerton and Mitton fisheries and the report by the area fisheries officer on fisheries activities. This comments on river conditions and fishing, migratory fish movement,an update on Middleton hatchery, salmon cages in Dalton-in-Furness, and Langcliffe hatchery. Finally the report adds about stockings by the authority, fish mortalities, fish disease and the monthy catches of salmon and sea trout for the 1980 season. The Fisheries Advisory Committee was part of the Regional Water Authorities, in this case the North West Water Authority. This preceded the Environment Agency which came into existence in 1996.

Southern Area Fisheries Advisory Committee 8th April, 1981

This is the report from the Southern Area Fisheries Advisory Committee meeting, which was held on the 8th April, 1981. It includes the report by the area fisheries officer on fisheries activities between December 1980 to February, 1981. This comments on river conditions and fishing, and an update on Hollingworth and the pilot hatchery, salmon cages in Dalton-in-Furness, and Langcliffe hatchery. Finally the report adds about stockings of coarse fish and non migratory trout added by the Angling Associations, fish mortalities and fish disease. The Fisheries Advisory Committee was part of the Regional Water Authorities, in this case the North West Water Authority. This preceded the Environment Agency which came into existence in 1996.

Northern Area Fisheries Advisory Committee 16th June, 1981

This is the report from the Northern Area Fisheries Advisory Committee meeting, which was held on the 16th June, 1981. It includes information on fisheries in the Solway Firth, fishing licence duties and the minutes of the last meeting held on the 30th March, 1981. The Fisheries Advisory Committee was part of the Regional Water Authorities, in this case the North West Water Authority. This preceded the Environment Agency which came into existence in 1996.

Central Area Fisheries Advisory Committee 7th September, 1981

This is the report from the Central Area Fisheries Advisory Committee meeting, which was held on the 7th September, 1981. It covers information including the consultation paper on the review of Inland and Coastal fisheries in England and Wales, a paper on 'A National Salmon Policy' and information on the response to an application for a professional eel trapper to fish for eels with fyke nets on Lake Windermere. The Fisheries Advisory Committee was part of the Regional Water Authorities, in this case the North West Water Authority. This preceded the Environment Agency which came into existence in 1996.

Northern Area Fisheries Advisory Committee 8th September, 1981

This is the report from the Northern Area Fisheries Advisory Committee meeting, which was held on the 8th September, 1981. It covers information including the consultation paper on the review of Inland and Coastal fisheries in England and Wales, and a paper on 'A National Salmon Policy'. The Fisheries Advisory Committee was part of the Regional Water Authorities, in this case the North West Water Authority. This preceded the Environment Agency which came into existence in 1996.

Southern Area Fisheries Advisory Committee 9th September, 1981

This is the report from the Southern Area Fisheries Advisory Committee meeting, which was held on the 9th September, 1981. It covers information including the consultation paper on the review of Inland and Coastal fisheries in England and Wales, and a paper on 'A National Salmon Policy'. The Fisheries Advisory Committee was part of the Regional Water Authorities, in this case the North West Water Authority. This preceded the Environment Agency which came into existence in 1996.