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

ab inito local vibrational modes of light impurities in silicon

We have developed a formulation of density functional perturbation theory for the calculation of vibrational frequencies in molecules and solids, which uses numerical atomic orbitals as a basis set for the electronic states. The (harmonic) dynamical matrix is extracted directly from the first order change in the density matrix with respect to infinitesimal atomic displacements from the equilibrium configuration. We have applied this method to study the vibrational properties of a number of hydrogen-related complexes and light impurities in silicon. The diagonalization of the dynamical matrix provides the vibrational modes and frequencies, including the local vibrational modes (LVMs) associated with the defects. In addition to tests on simple molecules, results for interstitial hydrogen, hydrogen dimers, vacancy-hydrogen and self-interstitial-hydrogen complexes, the boron-hydrogen pair, substitutional C, and several O-related defects in c-Si are presented. The average error relative to experiment for the aprox.60 predicted LVMs is about 2% with most highly harmonic modes being extremely close and the more anharmonic ones within 5-6% of the measured values.Comment: 18 pages, 1 figur

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