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h TMEDA (2 mL) was distilled into the reaction flask. All but-3 mL of THF was removed under vacuum, and 30 mL of diethyl ether was distilled into the reaction flask. The solution was filtered, and the solvent was removed by vacuum distillation. The solid product (red-orange) was washed with 40 mL of hexane, and solvent was removed under vacuum, giving a 91 9% yield of 2.2TMEDA. Slow evaporation of a EhO solution of 2-2TMEDA yielded crystals suitable for X-ray diffraction. ' H NMFt (200 MHz,

a b s t r a c tThe recruitment variability of the marine fish species Dicentrarchus labrax, Platichthys flesus and Solea solea was evaluated in the Mondego estuary (Portugal) from 2003 to 2007. The relationships between sea surface temperature, NAO index, coastal wind speed and direction, precipitation and river runoff prior to the estuarine colonization and the abundance of 0-group fish were evaluated using gamma-based Generalized Linear Models. Dicentrarchus labrax and P. flesus 0-group decreased in abundance towards the end of the study period, while S. solea, despite low abundance in 2004, increased in abundance in 2007. For D. labrax, river runoff, precipitation and east-west wind were significant; for P. flesus, precipitation, river runoff and both north-south and east-west wind components were significant parameters, while for S. solea only river runoff was important. Results were compared with recent projections for climate change scenarios, to evaluate their effects on future recruitment levels.

from commercial fishing vessels operating with gill nets and bottom trawls along the Portuguese coast in order to examine feeding habits, age and growth and reproduction. Citharus linguatula (Linnaeus, 1758), Lepidorhombus boscii (Risso, 1810) and Microchirus azevia (de Brito Capello, 1867) fed mainly on crustaceans, whereas Platichthys flesus (Linnaeus, 1758) fed mainly on echinoderms and crustaceans. Feeding activity was highest in spring and summer; females and small individuals showed the lowest vacuity index values. For all the species, significant differences were found in the proportion of prey items according to season, sex and size class. M. azevia had the largest diet spectrum. Ages were determined from sagittal otoliths. The von Bertalanffy growth equation coefficients differed between sexes. The asymptotic length L ∞ of females was higher than that of males, except in C. linguatula. The lowest growth coefficient was obtained for P. flesus (k=0.11 for males and k=0.10 for females) and M. azevia showed the highest growth coefficient estimates (k=0.40 for females and k=0.30 for males). The highest proportion of individuals at spawning stage was recorded in winter for L. boscii, P. flesus and M. azevia, and in autumn for C. linguatula.Keywords: flatfish, diet, growth, otoliths, reproduction, Portuguese coast. RESUMEN: Dieta, crecimiento y reproducción de cuatro especies de peces planos en la costa portuguesa. -Cuatro especies de peces planos fueron capturadas desde enero de 2003 hasta junio de 2005 por embarcaciones comerciales operando con redes de enmalle y arrastre de fondo, a lo largo de la costa portuguesa, con objeto de examinar los hábitos alimenticios, la edad, el crecimiento y el ciclo sexual. Citharus linguatula (Linnaeus, 1758), Lepidorhombus boscii (Risso, 1810) y Microchirus azevia (de Brito Capello, 1867), se alimentaron sobre todo de crustáceos. La dieta de Platichthys flesus (Linnaeus, 1758) estuvo compuesta principalmente por equinodermos y crustáceos. La mayor actividad alimenticia se observó en la primavera y el verano. Las hembras y los individuos más pequeños presentaron valores de índices de vacuidad más bajos. Para todas las especies se encontraron diferencias significativas en la proporción de ítems alimenticios según la estación, el sexo y la talla. M. azevia presentó el espectro más amplio de dieta. Las edades fueron determinadas a partir de los otolitos sagittae. Los coeficientes de la ecuación de crecimiento de von Bertalanffy fueron diferentes para los dos sexos. La talla asintótica L ∞ de las hembras fue mayor que la de los machos, excepto para C. linguatula. El coeficiente de crecimiento más bajo se observó para P. flesus (k=0.11 para los machos y k=0.10 para las hembras), M. azevia presentó el mayor coeficiente de crecimiento (k=0.40 para hembras y k=0.30 para machos). La mayor proporción de individuos maduros en L. boscii, P. flesus y M. azevia se observó en invierno y en C. linguatula en otoño.

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