The Slavonian Grebe (Podiceps auritus) has its European northern range limit in northern Norway, and is a species of national conservation concern due to its small population size and unknown population trend. Long-term monitoring at the range limit suggests breeding site use is in decline. We used annual occupancy data from 104 breeding lakes monitored since 1991 in northern Norway to investigate ...

<p>1. Outbreaks of herbivorous insects can have large impacts on regional soil carbon (C) storage and nutrient cycling. In northernmost Europe, population outbreaks of several geometrid moth species regularly cause large‐scale defoliation in subarctic birch forests. An improved understanding is required of how leaf C and nutrients are processed after ingestion by herbivores and what this means for ...

Sustainable management of wildlife populations can be aided by building models that both identify current drivers of natural dynamics and provide near-term predictions of future states. We employed a Strategic Foresight Protocol (SFP) involving stakeholders to decide the purpose and structure of a dynamic state-space model for the population dynamics of the Willow Ptarmigan, a popular game species ...

Breeding geese are the preferred prey of the Arctic fox Vulpes lagopus in the high-Arctic Svalbard archipelago. According to the <i>apparent competition hypothesis (ACH)</i>, less-abundant prey species (e.g. ptarmigan, waders and small passerines) will experience higher predation rates when breeding in association with the more common prey (geese), due to spill-over predation by the shared predator. ...

The autumnal moth (Epirrita autumnata) is a cyclically outbreaking forest Lepidoptera with circumpolar distribution and substantial impact on Northern ecosystems. We have isolated 21 microsatellites from the species to facilitate population genetic studies of population cycles, outbreaks, and crashes. First, PCR primers and PCR conditions were developed to amplify 19 trinucleotide loci and two ...

Climate change is expected to shift the boreal biome northward through expansion at the northern and contraction at the southern boundary respectively. However, biome-scale evidence of such a shift is rare. Here, we used remotely-sensed tree cover data to quantify temporal changes across theNorth American boreal biome from 2000 to . 2019. We reveal a strong northsouth asymmetry in tree cover change, ...

The increased spread of insect outbreaks is among the most severe impacts of climate warming predicted for northern boreal forest ecosystems. Compound disturbances by insect herbivores can cause sharp transitions between vegetation states with implications for ecosystem productivity and climate feedbacks. By analysing vegetation plots prior to and immediately after a severe and widespread ...

In this study we investigate the potential for using synthetic aperture radar (SAR) data to provide high resolution defoliation and regrowth mapping of trees in the tundra-forest ecotone. Using aerial photographs, four areas with live forest and four areas with dead trees were identified. Quad-polarimetric SAR data from RADARSAT-2 was collected from the same area, and the complex multilook polarimetric ...

Outbreaks by geometrid moths periodically cause mass mortality of trees and state changes in understorey vegetation in sub-arctic mountain birch forest in northern Scandinavia. In order to assess the short-term impacts of such disturbance on forest bird communities, we took bird censuses in forest where almost all birch trees had been killed by moth outbreaks 2–4 years before the study and in ...

Skogens helsetilstand påvirkes i stor grad av klima og værforhold, enten direkte ved tørke, frost og vind, eller indirekte ved at klimaet påvirker omfanget av soppsykdommer og insektangrep. Klimaendringene og den forventede økningen i klimarelaterte skogskader gir store utfordringer for forvaltningen av framtidas skogressurser. Det samme gjør invaderende skadegjørere, både allerede etablerte arter ...