Analysis of the Variations in the Spacial Distribution and Spawning of the Greenland Halibut In Divisions 3LMN (1990-93)

In this paper the geographic, bathymetric and seasonal distribution of the adult Greenland halibut stock exploited in the Flemish Pass area (Div. 3LMN) is analysed for the period 1990 - 1993 using data collected by observers on board the commercial fleet. A southward shift of the fishing area took place and adult fish and spawning activity were recorded in unsual areas. The main areas and seasons of spawning are described. A peak time for spawning has not been found and spawning females appeared evenly represented at any time of the day

Feeding Cycles of Greenland Halibut (Reinhardtius hippoglossoides) in the Flemish Pass Area in Relation to Catch Rates (1991-92)

The seasonal cycle in feeding activity of Greenland halibut shows a maximum in autumn in depths between 700 - 900 m. In deeper waters no seasonality appears at all. A 24-hour cycle in feeding activity is observed which is length related, with a daytime (6-12 hour interval) maximum in smaller fish (<60 cm) and at both sunset and night (18-24 hour and 0-6 hour intervals) in the largest fish (<80 cm). The intermediate length class (60-80 cm) shows a minimum in feeding activity in the afternoon (12-18 h) and in general a maximum in the interval 6-12 h, but in this group significant feeding activity occurs also at night. Catch rates decrease in autumn and reach a maximum in winter. In winter, increased catchs occurs mainly at night (0-6 h interval) and are based mainly in the smallest length class (<60 cm), which feeds least during this time interval. An inverse relationship between feeding intensity and catch rates is been observed

Standardized CPUE Indices for Greenland Halibut and American Plaice in NAFO Divisions 3LMNO Based on Spanish Commercial Catch Rates

Standardized cpue series using a Generalized Linear Model for Greenland halibut and American plaice in Division 3LMNO, based on catch and effort data from the Spanish trawl fleet since 1990 at depth intervals are presented. In the case of the Greenland halibut series, the largest proportion of the variance (45%) is explained by the factor ‘depth’, while in the American plaice on it is the factor ‘vessel’ (51%). The general trend observed in the Greenland halibut standardized CPUE in all divisions is a sharp increase in the indices from about 600 m, attaining maximum values between 900-1 000 m, and then decreasing at depths beyond 1 200 m. American plaice CPUE values at depths less than 500 m are very small in all divisions. The American plaice cpue series show two peaks one between 100-200 m. and the other between 400-500 m, decreasing sharply thereafter. The larger values in this species are observed in Div. 3L and 3N, while very small ones are in Div. 3M at any depth

Sexual Maturity and Spawning of the Greenland Halibut (Reinhardtius hippoglossoides) From Flemish Pass Area

10 páginas, 4 figuras, 3 tablas.-- Scientific Council MeetingPeer reviewe

Non-traditional resources: skate fishery and survey results in Division 3NO

Since 1993 a significant increase in the skate catches from the Spanish trawlers have been reported (Duran et al. 1996; Junquera et al. 1997). It was interpreted as a shift in the fishing strategy towards the exploitation of non-regulated species. Important skate by-catches are often taken in the Greenland halibut fishery, but at present a directed, though temporary, fishery has also been established. In this paper a review of the available information on this subject is presented

Histological Assessment of Sexual Maturity of the Flemish Cap Cod (Division 3M) in 1995

6 páginas, 5 tablas, 2 fisguras.-- Scientific Council Meetin

Sexual Maturity of Cod (Gadus morhua) in Flemish Cap (Div. 3M)

6 páginas, 3 tablas, 2 figuras.-- Scientific Council Meetin

Spanish Pelagic Redfish (Sebastes mentella) Fishery in the NAFO Regulatory Area (Division 1F) in 2000

In early October 2000 an exploratory fishing for oceanic redfish have been conducted by one Spanish pelagic trawler in the NAFO Regulatory Area of Div. 1F. One scientific observer was on board this vessel during the whole fishing period. The seasonal and geographic distribution pattern of the fishing effort in the Spanish oceanic redfish fishery is presented. A shift in the fleet activity towards the south and west is observed between the second and third quarter, approaching the vicinity of the NAFO Convention area. In the fourth quarter no fishing activity occurred in the Irminger Sea, and the fleet activity concentrated in NAFO Div. 1F. The length distribution in NAFO Div. 1F is similar to the one recorded in the NEAFC oceanic redfish fishery by the Spanish and German fleets in the upper 500 m layer. Only 11 % of the females and 5 % of the redfish males caught in NAFO 1F were immature (juveniles). The majority of the adult females were sexually inactive, while 49 % of the adult males were at the fully ripe stage, so it could be a mating concentration

Spawning biomass variation in Atlantic Cod (Gadus morhua) in Flemish Cap in Relation to Changes in Growth and Maturation

Drastic changes in both age- and length-at-maturity of cod (Gadus morhua) on Flemish Cap have been observed during this decade. In the present paper, growth by cohort in this period was analyzed and compared with the observed trend in maturation. Different cohorts displayed different growth rates, the strongest 1990 year-class showing fastest growth. The compensatory response to lower population density alone did not explain the decline in both age- and size-at-maturity. Strong changes in fishing pressure during the period could have provoked a size-selectivity for early maturity, i.e. genetic selection. An estimate of the spawning biomass, accounting for the corresponding size-at-age distributions, on a cohort basis is given. The influence of changes in spawning biomass and spawning stock biomass age structure on the probability of future stock rebuilding is also discussed. It is shown a low spawning biomass composed of young and recruited females will hardly rebuild the stock to historical levels