Human—bear conflicts occur frequently in the Pasvik Valley, Norway. We used a variant of the hair-trapping method with higher densities of traps (2.5 × 2.5 km grid) to detect brown bears moving near human settlements and livestock. We distributed 20 hair traps for one month close to a farm with frequent observations of grazing bears. The study area consisted of one area close to the farm, and one adjacent area without settlements. We collected 85 hair samples and identified 13 different individuals by STR analysis. In the farm area, we detected 4 different males once, and a female that was detected in both areas. In comparison, nine bears (2 males and 7 females) were detected for more than one week in the area without settlements, suggesting lower roaming activity. Conclusively, hair trapping has the potential to survey bears at specific locations of importance to the wildlife management.

The goldcrest (Regulus regulus) and the firecrest (Regulus ignicapilla) are sympatric over a large part of Europe, but with different abundance ratios. We studied the effects of geographical location, vicinity of the species range boundaries, habitat and climate factors on the goldcrest/firecrest abundance ratio. At the continental scale, a weighted multiple linear regression model resulted in four significant covariates: temperature, precipitation, forest type and occurrence rate (representing the vicinity of the species’ range boundaries). The firecrest dominates in warmer and more humid areas and its dominance is more pronounced in mixed forests. The projection of the model showed that in any combination of temperature, precipitation and occurrence rate, the probability to encounter the goldcrest is higher in coniferous forests. Studies in Croatia and the Czech Republic showed regional differences in habitat preferences related to forest type. A significant effect of the seasonal dynamics of precipitation was confirmed in Croatia. Climate change and changes in forestry may influence the distribution and abundance of these two Regulus species in Europe.

The killer whale (Orcinus orca) is a top predator and one of the most contaminated marine mammal species in the world. Due to different prey preferences and life styles, killer whale populations accumulate persistent pollutants differently, and therefore are exposed differently to this stress. Stress may express itself in a population as an increase in the relative number of individuals with asymmetric presentation of a trait that is normally symmetrical. This phenomenon is called fluctuating asymmetry. There are many environmental and genetic factors that can cause fluctuating asymmetry. We have used the symmetry of the killer whale's saddle patch pattern behind the dorsal fin as an indicator of fluctuating asymmetry in six Pacific Ocean populations. The southern resident killer whale population seems to be remarkably more asymmetrical than the other studied populations. Although many possible environmental factors could cause asymmetry, we suggest that small population size, development of reproductively isolated ecotypes and possible inbreeding as genetic factors are causing asymmetry in the southern resident population.

An understanding of the spatial organization of endangered species is particularly important in the light of habitat degradation and fragmentation. In bats, little is known about whether and how space is organized between individuals of the same species. We investigated space use in four maternity colonies of Bechstein's bats. We were able to show for the first time that spatial organization reflects the social organization in Bechstein's bats. We found a strong segregation of foraging ranges within colonies, and an even stronger segregation between different colonies. Our results suggest that the spatial organization of females is determined by foraging efficiency. It is crucial to determine the essential characteristics of both feeding and roosting core areas. We provide a precise prediction of effective population size and space requirements. Thereby, implications for the protection of Bechstein's bats and assumedly also for other bat species with a similar social and spatial organization can be deduced.

Shrews have very high metabolic rates and are often unintentionally starved in rodent live-traps during capture-mark-recapture (CMR) studies. Here, we suggest a shrew exit as a modification to rodent traps. To test whether this modification is (1) saving shrews and (2) not jeopardizing results of rodent captures, we compared captures in Ugglan traps with and without shrew exits, studying bank voles (Myodes glareolus) in a spruce forest in central Finland. Numbers of captured bank voles and body size of smallest juvenile bank voles were not affected by the shrew exit, while the number of captured common shrews (Sorex araneus) was reduced from 31 to 0 individuals per 100 trap nights. However, rare larger shrew species (> 8 g body weight) could not escape through the exit. A shrew exit can, therefore, save smaller shrew species in standard live-trapping of vole-sized rodents without affecting CMR data of the rodent.

The mating success of female spruce budworms was evaluated using the presence—absence of spermatophore in genitalia. Sampling was conducted in the 1970s in Atlantic Canada at 21 locations/years characterized by high budworm densities. More than 99.8% of in-flight females (captured at light or malaise traps) and migrant females (collected while ascending above tree canopies or in the airspace) were mated, which may reflect physiological constraints restricting flight in gravid females. About 85% of resident females (collected using sweep nets or by fogging trees with insecticide) were mated; mating success was low among young females collected early in the season and increased over time to reach a level similar (98%) to that of females that died from natural causes. These findings highlight the importance of unbiased estimates of mating success to evaluate the efficacy of mating disruption and the role of mate-encounter Allee effects on population dynamics.

We tested if within-lake differences in individual growth in an Arctic charr population before and after nutrient enrichment was due to a population bottleneck, for example as a result of strong selection for growth in a limited part of the population. The positive change in growth pattern after treatment was not coincident with a reduction in microsatellite variability, and various genetic estimators of demographic change did not indicate changes in population size. This suggests that the change in growth was not a result of only a limited part of the population responding, but an overall response.