10 documents found, page 1 of 1
Assessing the impact of environmental forcing on the condition of anchovy larva...
Teodosio, Maria; Garrido, Susana; Peters, J.; Miguel de Sousa Leitão, Francisco; Re, P.; Peliz, A.; Santos, A.M.P.Understanding the environmental processes affecting fish larvae survival is critical for population dynamics,"conservation purposes and to ecosystem-based fishery management. Using anchovies (Engraulis encrasicolus) of the Cadiz Gulf as a study case and considering the "Ocean Triad" hypothesis, we investigate the larval ecophysiological status and potential survival in relation to oceanographic variables. There...
Effect of temperature on the growth, survival, development and foraging behavio...
Garrido, Susana; Cristovao, A.; Caldeira, C.; Ben-Hamadou, Radhouan; Baylina, N.; Batista, H.; Saiz, E.; Peck, M. A.; Re, P.; Santos, A.M.P.The effect of water temperature on the growth, survival, development and foraging behaviour of European sardine Sardina pilchardus larvae was examined in the laboratory. First, the capability of early sardine larvae to cope with starvation was assessed at temperatures from 10 to 22 degrees C. Second, we examined under ad libitum feeding conditions and across the range of temperatures experienced by sardines dur...
Born small, die young: Intrinsic, size-selective mortality in marine larval fish
Garrido, Susana; Ben-Hamadou, Radhouan; Santos, A. Miguel P.; Ferreira, S.; M A Teodosio; Cotano, U.; Irigoien, X.; Peck, M. A.; Saiz, E.; Re, P.Mortality during the early stages is a major cause of the natural variations in the size and recruitment strength of marine fish populations. In this study, the relation between the size-at-hatch and early survival was assessed using laboratory experiments and on field-caught larvae of the European sardine (Sardina pilchardus). Larval size-at-hatch was not related to the egg size but was significantly, positive...
Larval and juvenile development of dusky grouper Epinephelus marginatus reared ...
Cunha, M. E.; Re, P.; Quental-Ferreira, H.; Gavaia, Paulo J.; Pousão-Ferreira, P.The larval development of the dusky grouper Epinephelus marginatus up to the benthic juvenile stage is described in detail to establish a reference for their larval identification. Development is described in terms of ontogenetic changes in morphology, growth, pigmentation, fin structure and skeletal structure. Larvae were reared in mesocosms at a mean temperature of 24·3◦ C, salinity of 36·5, dissolved oxygen ...
Horizontal spatial and temporal distribution patterns of nearshore larval fish ...
Borges, R.; Ben-Hamadou, Radhouan; Chicharo, Maria Alexandra Teodosio; Re, P.; Gonçalves, Emanuel J.There have been no previous studies of the composition of nearshore larval fish assemblages along the coast of Portugal. We aimed to describe the composition and horizontal distribution patterns of larval fish assemblages and their temporal dynamics near a rocky reef at depths shallower than 13 m (inshore) and at two miles (3.70 km) from shore (offshore), as well as along transects perpendicular to the shorelin...
Physical-biological interactions in the life history of small pelagic fish in t...
Santos, A. Miguel P.; Chicharo, Maria Alexandra Teodosio; Santos, Antonina dos; Moita, Teresa; Oliveira, P. B.; Peliz, A.; Re, P.This paper reviews relevant investigations conducted in the Western Iberia Upwelling Ecosystem (WIUE) on the dynamics of small pelagic fish (SPF), its relationship to climate changes and processes related to the ‘ocean triad’ (enrichment, concentration, transport/retention). In the last decades, a decline in the productivity of several SPF species (e.g., sardine and horse mackerel) was observed in the WIUE, whi...
Vertical distribution and trophic structure of the macrozooplankton in a shallo...
Morgado, F. M.; Pastorinho, M. R.; Quintaneiro, C.; Re, P.The zooplankton of the lower part of Canal de Mira (Ria de Aveiro) was sampled during one lunar month. The sampling programme consisted of nine 25 hour fixed-cycles, separated weekly. In each cycle, samples were collected every two hours at three depths (surface, mid-water and above the bottom) with a 500 µm mesh net. The overall effect of the tidal phase was analyzed, taking into account the day and depth of t...
Are sardine larvae caught off northern Portugal in winter starving? An approach...
Chicharo, Maria Alexandra; Esteves, E.; Santos, A. Miguel P.; Santos, Antonina dos; Peliz, A.; Re, P.Recently, winter upwelling events off western Iberia have become more frequent. This may affect the production and survival of sardines egss and larvae through increased offshore transport. By analysis of RNA: DNA ratios, we investigated the impact of winter upwelling events on the larval conditions of Sardina pilchardus larvaeas a function of oceanographic conditions and food availability. Larvae were collecte...
Estimation of starvation and diet variation of the RNA/DNA ratios in field-caug...
Chicharo, Alexandra; Chícharo, Luís; Valdes, L.; Lopez-Jamar, E.; Re, P.The aim of this study was to analyse the general larval condition, to determine the lncidence of starvation and to investigate the effect of time of day on RNA/DNA ratios among field-caught Sardina pilchardus (L.) larvae. The larvae were collected during 4 research cruises off northern Spain, during March, April, May and June 1992. A highly sensitive fluorometric method for nucleic acid quantification was appli...
Does the nutritional condition limit survival potential of sardine Sardina pilc...
Chicharo, Maria Alexandra; Chícharo, Luís; Valdes, L.; Lopez-Jamar, E.; Re, P.The aim of this study was to determine the nutritional condition of Sardina pilchardus larvae and the percentage of larvae that were starving at the time of capture. The survey was conducted, during the spawning season, in April and May of 1991 and 1992, off the northern coast of Spain. An accepted ¯uorimetric technique was used to determine the concentrations of both RNA and DNA and to calculate RNA/DNA ratio ...