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Evolutionary studies on optimal decisions or conservation guidelines are often derived by generalising patterns from a single population, while inter-population variability in life-history traits is seldom considered. We investigated here how survival and recruitment probabilities changed with age at different geographical scales using the encounter histories of 5523 European storm petrels from three Mediterranean colonies, and also how our estimates of these parameters might be expected to affect population growth rates using population matrix models. We recorded similar patterns among colonies, but also important biological differences. Local survival, recruitment and breeding success increased with age at all colonies; the most distant of three colonies (Marettimo Is.) showed the largest differences. Strikingly, differences in recruitment were also found between two adjacent colonies (two caves from Benidorm Is.). Birds marked as adults from Marettimo and Benidorm colonies had a different survival, whereas we found no differences within Benidorm. Differences in survival were no longer apparent between the two islands at the end of the study following a reduction in predation by specialist gulls at Benidorm. Since birds marked as fledglings mostly recruited near the end of the study, their overall survival was high and in turn similar among colonies. Results from our population matrix models suggested that different age-dependent patterns of demographic parameters can lead to similar population growth rates. Variability appeared to be greater for recruitment and the most sensitive parameter was adult survival. Thus conservation actions targeting this vulnerable species should focus on factors influencing adult survival. Differences in survival and recruitment among colonies could reflect the spatial heterogeneity in mortality due to predation and colony-specific density dependent processes. Results highlight the importance of taking into account the potential spatio-temporal heterogeneity among populations in vital rates, even in those traits that life-history theory considers less important in driving population dynamics. © 2009 Ecography., The Spanish Ministry of Science, funded the study through several grants (refs. BOS2003-01960, CGL2006-04325/BOS)

This paper reports on research conducted to elucidate the risk posed to the Sicilian population of the endangered lanner falcon Falco biarmicus feldeggii Schlegel by organochlorine (OC) pesticides and polychlorinated biphenyls (PCBs), as part of a wider study on contaminant risk to the lanner. Seventeen lanner nest sites were studied in northern and central Sicily. Sampling (in 2005)and analysis were carried out for selected OC pesticides and PCB congeners in lanner chick blood (15 chicks from 6 nest sites) and in two of the main lanner prey species, magpie Pica pica (36 individuals from 6 lanner nest sites) and rock dove Columba livia (10 individuals from 2 lanner nest sites). No OC and PCB residues were found in lanner chick blood above the detection limits, except for one solitary congener PCB153 (21.8 ng g 1 wet weight), suggesting that these contaminants do not pose a significant risk to lanner chicks in the study area. Magpie and dove appeared mostly free of contamination with OC pesticides, though contamination levels were significantly higher in magpie than in dove. The presence of exceptional DDE and HEOD values in ;8% of the P. pica sample, and one P. pica sample showing recent DDT contamination, may indicate a local OC pesticide hazard to some lanner. Future research to further elucidate the contaminant risk to lanner in Sicily is suggested.

Le specie alloctone in Italia: censimenti, invasività e piani di azione

The worldwide spread of invasive species is considered to be one of the main causes of global amphibian declines and the loss of biodiversity in general. The African Clawed Frog, Xenopus laevis, shows a strong ability to establish populations and invade various geographic regions. In 2004 X. laevis was found in Sicily for the first time. The Sicilian population is probably the largest in Europe with a range of about 225 km2 in an area characterized by numerous agricultural ponds. This high density of ponds has potentially facilitated the dispersal of X. laevis. The frogs can move far from rivers or watercourses by utilizing the ponds as suitable "islands". The analysis of their diet shows that the aquatic larvae of nektonic insects comprise the major portion in terms of mass while small planktonic crustaceans are the most numerous component. There is a significant difference between the diet of adults and juveniles.

Variation of the Sicilian pond turtle, Emys trinacris, is described, based on morphological data of more than 200 adult and immature turtles and mtDNA sequences of 31 new known-locality specimens. Emys trinacris is morphologically more variable than thought before. There exist pronounced population-specific differences. Adults are barely distinguishable from Emys orbicularis galloitalica. Hatchlings of E. trinacris are, however, significantly different patterned, allowing immediate species determination. Moreover, hatchlings of E. trinacris seem to be on average smaller and lighter than in E. orbicularis. This could be related with different reproductive strategies. Coloration polymorphism of adult Sicilian pond turtles comprises fair part of variation known in E. orbicularis. Thus, adult E. trinacris might have preserved the whole array of variation of the last common ancestor with E. orbicularis.We hypothesize that similarity of certain southern E. orbicularis subspecies and E. trinacris on one hand and pronounced differences in size, coloration and pattern of northern E. orbicularis subspecies on the other result from stabilising selection in the north. While dark coloration and large body-size seem to be beneficial in the north, light coloration and small size could be simply not disadvantageous in the south, allowing coloration polymorphisms in E. trinacris and southern E. orbicularis subspecies. Further, the term ‘cryptic species’ and its meaning in regard to species concepts and bar-coding is discussed. It is concluded that species delineation based on mtDNA barcoding requires application of a Phylogenetic Species Concept. Under the Biological Species Concept, animal mtDNA is not always an ideal tool for delineating species boundaries because taxa with monophyletic mitochondrial gene trees are neither necessarily genetically isolated nor must represent the same Biological Species. Cryptic species are nothing special in nature because difficulties with their identification are due to deficits in cognitive abilities of man. This is illustrated by the fact that distinct live stages of ‘cryptic species’ may differ to various degrees from similar species, as is the case in hatchlings and adults of E. trinacris and E. o. galloitalica.