The bleak, Alburnus alburnus, is an invasive fish in the Iberian Peninsula, where this species mainly disturbs the higly endemic fauna via competition and aggression. Despite this impact, information on bleak autecology is scarce in the Iberian Peninsula, with no data on growth and reproduction. The aim of the present study was to compare bleak populations across four Iberian streams: Muga, Fluviá, Cardener and Foix (northeastern Iberian Peninsula).These streams have similar enviromental conditions at the regional scale (e.g. Mediterranean climate, geomorphology). In Muga and Foix streams, bleak showed lower growth rate and back-calculated lenght at age 2. Body condition was lower in Foix streams, whereas lenght at maturity was higher. In Muga stream, the proportiun of females was lower. In Cardener stream, bleak showed higher back-calculated lenght at ages I and 2, growth rate, body condition and reproductive investment. Results showed that bleak populations are able to display wide phenotypic plasticity in small Mediterranean-type rivers. Specifically, bleak population "health" appears to be better in Cardener stream, whereas it is worse in Muga and Foix streams. Present findings suggest that inter-population plasticity allows bleak more successfully to invade Mediterranean fresh waters in the Iberian Peninsula.
Wild boar population structure was studied in two well-preserved forests of western Iberian Peninsula, one located in a typically Mediterranean zone (vegetation mainly holm oak Quercus ilex and various tall-shrubs species), and the other in a more Atlantic area (mainly oak Q. pyrenica but with abundant cork oak Q. suber in some places). Data were colleted during hunts in monterías’ area between the 1994/95 and 2000/2001 hunting seasons (October to February). 972 hunted wild boars were sexed and aged in the field, using growth patterns and tooth attrition. The mean age of hunted wild boars differed in the two zones. 2.11 years old in holm oak forest, and 1.78 years old in oak forest. This difference may result from shurb cover density and its effect on hunting dog, efficiency in rooting out wild boar. However, mean age was similar other zones of Europe. Proportionately more females were taken than males demonstrate the usefulness of Mediterranean hunting in contributing to management and conservation.