Understanding the dynamics of a disease spread requires information on various aspects of the ecology of vector species. The habitat selection and habitat use of raccoon dogs (Nyctereutes procyonoides), badgers (Meles meles), red foxes (Vulpes vulpes) and domestic cats (Felis silvestris catus) were studied in southeastern Finland between 2000 and 2004. The aim was to find out the habitats where these species are most likely to come into contact and possibly transmit diseases, such as rabies, to each other. Raccoon dogs and badgers showed preference for fields and deciduous forests in all scales studied. Raccoon dogs favoured also watersides in summer and young mixed forests in autumn. Foxes and cats showed more individual variation in their habitat selection/use. Analysis of the overlapping areas of seasonal home ranges further demonstrated the significance of deciduous forests and fields. These, and also young mixed forests and open areas, could be called the risky habitats in terms of rabies spread.

Postglacial northward expansions from distinct southern European refugia have lead to the formation of several secondary contact zones between species. These zones are providing growing insights into the relevance of introgressive hybridization in shaping patterns of genetic diversity, and into the evolutionary processes involved in the completion of reproductive isolation barriers. Using both nuclear (9 allozyme loci) and mitochondrial (PCR-RFLP of a cytochrome b gene fragment) diagnostic markers we investigated the genetic patterns of variation across a zone of parapatry between the two European treefrogs Hyla arborea and H. intermedia. Neither F₁ and F₂ hybrids nor backcrosses were identified, indicating the lack of current gene exchange between the two species. However, introgressed alleles were observed in both species and in all markers analysed, which testifies to the occurrence of past events of introgressive hybridization. A wide variation in the frequencies of introgressed alleles was observed between loci and between the two species, suggesting the action of differential selective filtering. The historical context for the occurrence of secondary contact between the two species and its evolutionary implications are discussed, together with the possible role of human disturbance and/or reinforcing selection in leading to the observed absence of ongoing gene flow between them.

I studied a dataset of surface sediment samples from 80 lakes with zoological macroremain analysis to assess the potential of fossil ceratopogonids (Diptera: Ceratopogonidae), ephemeropterans (Insecta: Ephemeroptera), trichopterans (Insecta: Trichoptera) and oribatid mites (Acarina: Oribatida) as palaeolimnological indicators in Finland. Results showed that late-winter hypolimnetic oxygen and climatic variables were most important in influencing the occurrence and abundance of these taxa. Of the ceratopogonids, the Bezzia type was an indicator of elevated hypolimnetic oxygen conditions, warm climate and oligotrophy, while the Dasyhelea type indicated low hypolimnetic oxygen conditions, moderately cool climate and mild acidity. Ephemeropterans, trichopterans and oribatids indicated warm climatic conditions and oribatids were also indicative of elevated oxygen conditions and small oligotrophic lakes. Results of this study can be useful in palaeolimnological studies because the fauna examined provides a valuable supplementary data source for multiproxy studies.

Some plumage patterns in birds, such as irregularities of feathers, are potential amplifiers because they can reveal damage by conspecifics and therefore social status. We experimentally manipulated the pattern of the white cheeks of male great tits (Parus major) in order to simulate the effects of peckings by others and thus investigate possible changes in dominance during agonistic encounters at artificial feeders exposed to different risks of predation during winter. As predicted, manipulated birds were displaced by controls from safe feeders, and performed a lower number of aggressions and with lower success, although they did not receive more aggressions as expected from the fact that efficient agonistic displays can avoid the occurrence of overt aggressions. Thus, our manipulation changed the social status of birds by converting individuals with manipulated cheeks into subordinates. We propose that cheek colour uniformity acts as an amplifier of the outcomes of aggressions in great tits.

Competition among species with similar ecological requirements may preclude species coexistence. However, species with similar requirements may coexist under determinate environmental conditions. Major effort is being dedicated to conserve the golden eagle (Aquila chrysaetos) and Bonelli's eagle (Hieraaetus fasciatus) in Spain, two raptors with similar ecological requirements. This work analyses how some key ecological factors correlate with the coexistence of the two eagles, which may help to optimize the conservation plannings of the two species. Findings show that low human population density favours eagle coexistence, because human presence is harmful for both eagles. Temperature is an important factor affecting the segregation of the two eagles, with Bonelli's eagle dwelling in warmer zones than the golden eagle, but overlapping in squares with intermediate temperature. High prey diversity facilitates the coexistence of the two eagles, possibly because it encourages trophic segregation. Conservation planning for both species would be enhanced by the protection of zones with low human population density, intermediate temperature, and high prey diversity, which seem to favour the coexistence of the two eagles.

We investigated reproduction and mortality of raccoon dogs (Nyctereutes procyonoides) in the Białowieża Primeval Forest (eastern Poland). The species invaded the forest in 1955 and is more common than native species of medium-sized carnivores. The mean litter size of raccoon dogs, based on placental scars and foetuses was 8.4 (SD = 2.0). Mortality of pups was 61% during the first three months following parturition. Of 82 cases of raccoon dog deaths recorded from 1996 to 2006, 55% were caused by natural factors (predation and diseases), 40% were human-related (vehicle collisions, harvest, poaching), and 5% were indeterminable. Rabies was the most important disease. The main predators of raccoon dogs were wolves (Canis lupus) and domestic dogs (Canis familiaris). Almost all raccoon dogs killed by cars were dispersing juveniles. We did not find differences in causes of mortality between collared and uncollared individuals. The annual survival rate of radio-tracked raccoon dogs (n = 18, 1997–2000) was 0.38 (SD = 0.05), and did not differ between males and females. Survival of raccoon dogs varied seasonally. It was highest in winter (0.82) when raccoon dogs settle in burrows, which may protect them against predation. The life table constructed based on the age at death indicates that mortality was highest in the first year of the raccoon dog life (0.82), and lower in the following years (0.58–0.68). Most raccoon dogs (98%) died during the first three years of their life and the maximum life span was 7 years. Life expectancy at birth was 0.8 years.

The goal of this study was to evaluate the relative role of some central intrinsic and extrinsic factors affecting reproduction in the tawny owl in southern Finland, near the northern limit of the species' range. The data included 153 successful nestings of pairs of birds in which both mates were identified, sexed, aged, and measured. Brood size was constrained by clutch size that, in turn, could be explained by the positive influence of female age. Female condition was positively influenced by both male condition and female age, while male condition was positively related to the age of male. These intrinsic factors outweighed the effects of extrinsic factors examined. However, these probably prominent extrinsic factors, such as general food supply and winter weather conditions, seemed to be inadequately quantified for use in the present study. Therefore, future studies should proceed by evaluating variables that characterize more accurately those environmental conditions where the studied population lives.