During the 20^th century the hare population in Ireland exhibited a ‘regime shift’ from a state where numbers were stable but cyclic with a periodicity of 8 years, to one in which cyclicity was lost and numbers declined dramatically. This was associated with a distinct ‘tipping point’ linked to early destablisation of the climate and the onset of agricultural intensification.

We incorporated the impacts of two toxicants (DDE and PBDEs) in a stage-based matrix model of a density-dependent peregrine falcon population. At high population densities, toxicant impacts were mitigated by an alleviation of intra-specific competition. This mitigation was absent at low population densities, implying that anthropogenic toxicants may affect wildlife particularly in case of small, hence more threatened populations.

Different stages of reproduction have different energetic demands and the importance of resource availability is likely to change throughout the breeding season and affect life-history decisions. To test for temporal heterogeneity in limitations set by food supply we carried out a supplementary feeding experiment in the field with the Common buzzard (Buteo buteo).

We present an analysis of all major changes observed in abiotic and biotic variables of a limnic and terrestrial biota, within a high Arctic ecosystem in Greenland, over a period of 15 years. Results showed multiple biotic changes, not uniformly distributed across trophic levels and that differ qualitatively and quantitatively between terrestrial and limnic biota.  

Decades of studies on the ecological impacts of non-timber forest products harvest, reveal that harvest can affect population dynamics. However, effects of harvesting such products on life history traits has been largely ignored. We will discuss the management implications of the effects of foliage and bark harvest on the longevity and age at maturity for African mahogany. 

We studied interactions involving three species of cruciferous plants that exhibit different seasonal phenologies on the development of a multivoltine herbivore, the large cabbage white butterfly, and its gregarious endoparasitoid wasp. We found that the effects on development of the herbivores and its parasitoid differed among the plant species more significantly than across different generations.

The release of chemicals following herbivore grazing on primary producers may provide feeding cues to carnivorous predators. Such tritrophic interactions in the plankton release the climate-relevant gas dimethylsulphide (DMS). Our modelling results indicate that infochemical-mediated tritrophic interactions have important consequences for plankton bloom dynamics, potentially impacting climate and food security.