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The Hermann's tortoise (Testudo hermanni) is an endangered land tortoise distributed in disjoint populations across Mediterranean Europe. We investigated its genetic variation by typing 1 mitochondrial locus and 9 nuclear microsatellites in approximately 300 individuals from 22 localities. Our goal was to understand the relative impact of natural and human-mediated processes in shaping the genetic structure and to identify the genetic priorities for the conservation of this species. We found that 1) all geographic areas are highly differentiated, mainly as a function of their distance but with a clear genetic discontinuity (F st values larger than 0.4) between the Eastern and the Western subspecies; 2) the contact zone between subspecies is located farthest to the west than previously believed, and it probably coincides with the delta of the largest Italian river; 3) extinction events due to climatic conditions in the Upper Palaeolithic and subsequent human-mediated translocations in the Neolithic possibly explain the unexpected similarity among Spain, Sicily, and Corsica. For conservation purposes, the large majority of genetic pools appears native although hybridization among subspecies, related to extensive 20th century trade of tortoises across Europe, is observed in Spain and some Italian samples. Most populations do not seem at immediate risk of low genetic variation, except the French population, which has very low nuclear genetic diversity (heterozygosity = 0.25) and where 50 out of 51 sampled animals shared the same mitochondrial sequence. In general, restocking and reintroduction plans should carefully consider the genetic background of the individuals.

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We studied nest site selection and breeding success of Black-crowned Night-Herons (Nycticorax nycticorax) and Little Egrets (Egretta garzetta) in the Axios Delta (Greece) from 1988 to 1990. Both species nested above the middle of tamarisks and alders. Nest density varied each year from 333.3 nests/ha to 646.2 nests/ha for Blackcrowned Night-Herons and 291.7 nests/ha to 421.5 nests/ha for Little Egrets. Black-crowned Night-Herons started to breed earlier than Little Egrets, also placing their nests higher (mean nest height: 4.21 ? SD of 0.80 m and 3.54 ? SD of 0.71 m for Black-crowned Night-Herons and Little Egrets, respectively). The nearest neighbors were conspecifics for Black-crowned Night-Herons and heterospecifics (Black-crowned Night-Herons) for Little Egrets. The mean distance of the nearest neighbor was similar in both species (1.02 ? SD of 0.46 m and 1.11 ? SD of 0.37 m for Black-crowned Night-Herons and Little Egrets, respectively). In contrast to late-nesting Little Egrets that located their nests lower, Black-crowned Night-Herons maintained a constant nest distance from the ground. The mean clutch size (3.40 ? SD of 0.60 and 4.32 ? SD of 0.81 for Black-crowned Night-Herons and Little Egrets, respectively) and the mean chick survival per nest (2.48 ? SD of 0.95 and 2.53 ? SD of 1.28 for Black-crowned Night-Herons and Little Egrets, respectively) of both species varied among the study years. No variation was observed in the means of clutch size and chick survival per nest of Black-crowned Night-Herons among the 3 sub-periods of the breeding season. Little Egret clutch size and mean number of eggs hatched was smaller in late nesters, but no difference was observed in chick survival per nest between early and late nesters. Nest placement did not affect chick survival in Black-crowned Night-Herons and only marginally in Little Egrets.

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In the National Park of Dadia-Lefkimi-Soufli Forest (Dadia NP, Greece), seven "target" PCBs and 16 organochlorine pesticides (OCs) were analysed in blood samples of cinereous vultures (Aegypius monachus) and Eurasian griffon vultures (Gyps fulvus). PCB congeners 138, 153 and 180 predominated in both species' blood samples. In both species, no differences were detected in congener levels between successive age classes, but in cinereous vulture, there were significant differences between adult and nestling in levels of PCB 28, 52, 101, 118 and between nestling and immature in levels of PCB 101. Regarding pesticides, p,p'-DDE dominated in both vultures followed by β-HCH, lindane and endosulfan sulphate, but ∑OCs were higher in griffon vulture. Significant differences were detected only between nestling and sub-adult cinereous vultures in heptachlor levels and between nestling and adult in p,p'-DDT. The origin of pollutants differs between the two vulture species and pollution patterns may not reflect those at Dadia NP.