Biological characteristics of the catch from the 1990-91 Pacific Herring, Clupea pallasi, roe fishery in California

The Tomales-Bodega Bay catch during the past two seasons has been from the northern part of Bodega Bay, due to the closure of the Tomales Bay fishery. In the Tomales-Bodega Bay area, 4-, 5-, and 6-yr-old herring Clupea pallasi, comprised 79% by number of the 1990-91 season's gill net catch. The number of 4-yr olds (1987 year class) increased to 21% of the gill net catch. Four-yr olds are an indicator of recruitment strength into the gill net fishery. Average length of herring in the Tomales-Bodega Bay area gill net catch decreased due to a shift to younger herring in the catch, as well as, poor growth characteristics during 1990. Herring age and size data obtained from Tomales Bay with a variable mesh research gill net were similar to data from San Francisco Bay obtained with the same net. All age classes were taken and herring ranged in length from 148 mm to 226 mm. In San Francisco Bay, the age composition of the gill net catch was also primarily 4-, 5-, and 6-yr-old herring, which comprised 79% of the catch. In the round haul fishery 2- and 3-yr-old herring dominated, comprising 72% of the catch. The average length of herring in the San Francisco Bay gill net and round haul catches decreased. Both are the lowest recorded average lengths by the respective gear types except for the 1983-84 El Nino season. Observed poor growth characteristics this season are attributed to reduced upwelling off central California in 1990. (26pp.

Ontogenetic changes in cutaneous and branchial ionocytes and morphology in yellowfin tuna (Thunnus albacares) larvae.

The development of osmoregulatory and gas exchange organs was studied in larval yellowfin tuna (Thunnus albacares) from 2 to 25 days post-hatching (2.9-24.5 mm standard length, SL). Cutaneous and branchial ionocytes were identified using Na+/K+-ATPase immunostaining and scanning electron microscopy. Cutaneous ionocyte abundance significantly increased with SL, but a reduction in ionocyte size and density resulted in a significant decrease in relative ionocyte area. Cutaneous ionocytes in preflexion larvae had a wide apical opening with extended microvilli; however, microvilli retracted into an apical pit from flexion onward. Lamellae in the gill and pseudobranch were first detected ~ 3.3 mm SL. Ionocytes were always present on the gill arch, first appeared in the filaments and lamellae of the pseudobranch at 3.4 mm SL, and later in gill filaments at 4.2 mm SL, but were never observed in the gill lamellae. Unlike the cutaneous ionocytes, gill and pseudobranch ionocytes had a wide apical opening with extended microvilli throughout larval development. The interlamellar fusion, a specialized gill structure binding the lamellae of ram-ventilating fish, began forming by ~ 24.5 mm SL and contained ionocytes, a localization never before reported. Ionocytes were retained on the lamellar fusions and also found on the filament fusions of larger sub-adult yellowfin tuna; however, sub-adult gill ionocytes had apical pits. These results indicate a shift in gas exchange and NaCl secretion from the skin to branchial organs around the flexion stage, and reveal novel aspects of ionocyte localization and morphology in ram-ventilating fishes

Myxozoan pathogens in cultured Malaysian fishes. I. Myxozoan infections of the sutchi catfish Pangasius hypophthalmus in freshwater cage cultures

Cage-cultured sutchi catfish Pangasius hypophthalmus (Sauvage, 1878), a favourite food fish in Southeast Asia, proved to be infected by 6 myxozoan species. Three species belonged to the genus Hennegoides (H. berlandi, H. malayensis, and H. pangasii), 1 to Henneguya (H. shariffi) and 2 to Myxobolus (M. baskai, and M. pangasii). Five myxozoans infected the gills and 1 was found on the spleen. Myxozoans infecting the gills were characterised by a specific site selection. H. shariffi sp. n. and H. berlandi sp. n. formed plasmodia in the multi-layered epithelium of the gill filaments. Of the 2 vascular species H. pangasii sp. n. developed in the gin arteries, while M. baskai sp. n. infected the capillary network of the gill lamellae. Plasmodia of H. malayensis sp. n. were found inside the cartilaginous gill rays of the filaments. Large plasmodia of M. pangasii sp. n. were located in a groove of the spleen but they affected only the serosa layer covering the spleen

Britain and the Bomb: Nuclear Diplomacy, 1964- 1970 (Book Review) by David James Gill

Review of Britain and the Bomb: Nuclear Diplomacy, 1964- 1970 by David James Gill

Myxozoan pathogens in cultured Malaysian fishes. II. Myxozoan infections of redtail catfish Hemibagrus nemurus in freshwater cage cultures

Cage-cultured Asian redtail catfish Hemibagrus nemurus (Valenciennes, 1840), a popular food fish in Southeast Asia, proved to be infected by 3 myxozoan species. All the 3 species belonged to the genus Henneguya: 2 were identified as H. mystusia Sarkar, 1985 and H. hemibagri Tchang et Ma, 1993, while the other was described as H, basifilamentalis sp. n. All plasmodia were found in the gills and were characterised by a specific site selection. H. mystusia formed plasmodia in the multi-layered epithelium between the gill lamellae and in the non-lamellar edge of the gill filaments, while H. hemibagri developed in the capillary network of the lamellae. H. basifilamentalis sp. n. had large oval plasmodia located deep among the filaments just above the gill arch

Biological characteristics of the gill net catch from the 1989-90 Pacific herring, Clupea pallasi, roe fishery in California

The Tomales-Bodega Bay catch this season was from northern Bodega Bay, and the possibility that this season's catch may be from a different stock must be considered. In the Tomales-Bodega Bay area, 5- through 8-yr-old herring, Clupea pallasi, comprised 89% by number of the 1989-90 season's gill net catch. Recruitment of the 1986 year class (4-yr olds) was relatively poor, comprising only 9% of the gill net catch by number. Average length of the Tomales-Bodega Bay area gill net catch increased to 204 mm BL because the number of 3- and 4-yr olds in the catch decreased to 11%, the lowest level since the 1982-83 season. The average weight at age of 4-through 8-yr-old herring did not change significantly this season. In San Francisco Bay, for the first time since the 1982-83 season, 5-, 6-, and 7-yr-old herring were the dominant age groups comprising 79% by number of the gill net catch. This reverses a trend toward younger and smaller herring in the gill net catch. The average length of herring in the San Francisco Bay gill net catch increased to 196 mm BL. The change in the size and age composition is attributed to better enforcement of the 2 1/8 in. gill net mesh regulation. The sex ratio of the gill net catch also improved. Females comprised 53% of the catch in both San Francisco and Tomales bays. (19pp.

Biological characteristics of the catch from the 1985-86 Pacific herring, Clupea harengus pallasi, roe fishery in California

In Tomales Bay, 4-, 5-, and 6-yr-old herring, Clupea harengus pallasi, composed 70% by number of the 1985-86 season's catch. In San Francisco Bay, 2-, 3-, and 4-yr-old herring composed 78% by number of the roundhaul catch, and 4- and 5-yr-old herring composed 64% by number of the gill net catch. The percent of 4-yr-old herring in both the Tomales Bay catch (25% and San Francisco Bay gill net catch (39%) is at a high level for the second year in a row. Recruitment of 2-yr-old herring into the San Francisco Bay roundhaul fishery was about average, with 2-yr-old herring composing 33% of the catch. The mean length of herring in the San Francisco Bay roundhaul catch increased to 178 mm BL, while the mean length of the gill net catch remained 196 mm BL. The mean length of the Tomales Bay catch decreased to 198 mm BL due to the increased number of 3- and 4-yr-old herring in the catch. (18pp.

Investment prospects in inland capture fisheries with special reference to small reservoirs: the exclusive fishing right licence model

The paper discusses simple methods of estimating fish yield from small reservoirs and establishes 2 indices of fish yield based on: 1) the relationship between the catch per boat in artisanal commercial fish landings and the catch per unit effort in experimental gill-net survey; and also, 2) the relationship between standing crop of fish in reservoirs and catch per unit effort in experimental gill-net survey. The paper then elaborates on the methods of utilizing these simple relationships in managing small reservoirs in Nigeria based on the principle of exclusive fishing right licence with the objective of attracting investors into this viable inland fishery investment project hitherto untappe

Negotiating 'Normal': the Management of Feminine Identities in Rural Britain

This paper examines the management of feminine identities in a women\'s rugby team in a rural British community. In so doing, the issue of new, and potentially problematic, forms of femininity are explored, with their attendant social consequences. The team, known as the Jesters, is situated in a social context which is dominantly masculine and heterosexist, with rigidly enforced gender roles. Due to their participation in rugby, a \'man\'s game\', the Jesters are threatened with marginalisation for their apparent failure to conform to, and potential disruption of, established gender norms. This threat is managed through the performance of certain \'inauthentic\' feminine identities (hyper-femininity and heterosexuality) on the part of the entire team. It is this \'team identity\' which lies at the heart of this paper. This paper therefore examines the group dynamics of identity performance and negotiation. In negotiating \'normal\' the Jesters are forced to confront changing gender norms and social contexts within the team itself. This paper also examines the difficulties faced by individuals when their own interests are opposed to the interests of the group of which they are a part. Although largely uncaring about the private lives of team members, the heterosexual members of the Jesters refuse to tolerate the performance of alternative versions of femininity when it may result in the exclusion of the team as a whole. This paper therefore examines the differing interests of heterosexual and lesbian femininities within a potentially marginalised group and some of the coping mechanisms adopted by both groups to develop a coherent team image.Normal, Identity, Gender, Sexuality, Performance