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Intensive forest management and landscape degradation are threats to amphibian populations. We modelled and compared the extinction and colonization dynamics of the great crested newt in four different spatial contexts that describe landscape change from past to present and future forest landscapes in eastern Finland. In future landscape scenarios, we explored the effects of two forest use intensities with different logging rotation times. The introduction of fish into breeding ponds has been the main cause of local extinctions of the great crested newt. In the future, intensifying land-use and shorter logging rotation will decrease the connectivity between ponds the most. In conservation planning, more attention should be paid to the spatial arrangement of habitat patches, especially if the intensity of human impact will increase. Conservation effort must be targeted towards securing source ponds in the core area and towards enhancing connectivity.

Many amphibian species spend part of their life cycle in terrestrial habitats. However, their exact requirements regarding terrestrial habitats have often remained enigmatic. We aimed to compare the terrestrial habitat use of a common (smooth newt) and a rare newt (great crested newt) species around their breeding ponds, to see whether habitat preferences are linked to the rarity of a species. We tested the effects of forest habitat characteristics on newt populations of seven ponds. The ponds were monitored with terrestrial drift fences at different distances and in different habitats surrounding seven ponds in southeastern Finland during 2 years. We fitted all models using a Poisson generalized linear mixed model. Both newt species distinctly favored forests with high understory vegetation cover. Captures were most numerous in the old forests directly adjacent to the ponds. Both the common species and the rare species showed similar habitat use, but there was an indication that the rare species avoided clear-cut areas and had more need for the shelter provided by canopy and field-layer vegetation, especially when the distance to pond increased. Based on our findings, the maintenance of sheltering vegetation around the ponds is very important, especially for the rare species. However, this requires the retention of both field-layer and canopy coverage, and specific management principles—such as avoiding clear-cuts—should be adopted to maintain favorable conditions.

For centuries, pastoralists have influenced savanna ecology through their construction of settlements, traditional movement patterns in search of forage, water and safety for their livestock. Construction of settlements initiates localised changes in the vegetation due to clearance of vegetation at construction and collection of construction materials. During the occupation period a lot of dung is deposited in and around settlements. When pastoral families abandon settlements and move away, they leave behind mud huts and livestock corrals surrounded by fences. These sites become nutrient-rich patches supporting a different abundance and diversity of plants and large mammals compared to the rest of the savanna. This study aimed to broaden our understanding of how pastoral land use influences plant diversity in East African savannas. Past work on the effects of settlements has been done in dry places (

Amphibian declines have been reported worldwide during the last decades. In this study, we focused on the endangered great crested newt (Triturus cristatus), which has suffered from intensive forestry and past mire ditching in the northern verge of its distribution. We collected data from 46 breeding ponds in eastern Finland during 2005–2011 using dip-netting. We modeled breeding success with cost-effective methods by using site-level forest data. The results highlight the importance of herb-rich forests in the vicinity of breeding ponds. Based on the results possible new breeding sites can now be located based on the presence and size of types of nutrient-rich forest, proportion of deciduous trees, young stands, shading and unfavorable habitats in the vicinity of ponds. Also practical conservation measures, like creating new ponds within a certain area, can now be allocated more accurately using the same variables.