Philip J. Harrison

Uppsala University | UU · Department of Pharmaceutical Biosciences

Understanding spatiotemporal population trends and their drivers is a key aim in population ecology. We further need to be able to predict how the dynamics and sizes of populations are affected in the long term by changing landscapes and climate. However, predictions of future population trends are sensitive to a range of modeling assumptions. Dead...

Understanding spatiotemporal population trends and their drivers is a key aim in population ecology. We further need to be able to predict how the dynamics and sizes of populations are affected in the long term by changing landscapes and climate. However, predictions of future population trends are sensitive to a range of modelling assumptions. Dea...

Modelling spatio‐temporal changes in species abundance and attributing those changes to potential drivers such as climate, is an important but difficult problem. The standard approach for incorporating climatic variables into such models is to include each weather variable as a single covariate, whose effect is expressed through a low‐order polynom...

Climate change is expected to drive the distribution retraction of northern species. However, particularly in regions with a history of intensive exploitation, changes in habitat management could facilitate distribution expansions counter to expectations under climate change. Here, we test the potential for future forest management to facilitate th...

Understanding the relative importance of different ecological processes on the metapopulation dynamics of species is the basis for accurately forecasting metapopulation size in fragmented landscapes. Successful local colonization depends on both species dispersal range and how local habitat conditions affect establishment success. Moreover, there i...

The extensive spatial and temporal coverage of many citizen science datasets (CSD) makes them appealing for use in species distribution modeling and forecasting. However, a frequent limitation is the inability to validate results. Here, we aim to assess the reliability of CSD for forecasting species occurrence in response to national forest managem...

Quantifying species turnover is an important aspect of biodiversity monitoring. Turnover measures are usually based on species presence/absence data, reflecting the rate at which species are replaced. However, measures that reflect the rate at which individuals of a species are replaced by individuals of another species are far more sensitive to ch...

A key aspect of monitoring regional changes in biodiversity is to quantify the temporal turnover in communities. Turnover has traditionally been assessed by observing range change. However, we are often interested in trends in biodiversity of large regions as opposed to single sites, as with C onvention for B iological D iversity targets. Extinctio...

Partitioning biodiversity change spatially and temporally is required for effective management, both to determine whether action is required and whether it should be applied at a regional level or targeted more locally. As biodiversity is a multifaceted concept, comparative analyses of different indices, focussing on different components of biodive...

Bird populations are seen as useful indicators of the health of wildlife and the countryside because they occupy a range of habitats, they tend to be towards the top of the food chain, and data is provided by long‐term surveys. Hence, many countries apply wild bird indicators ( WBI s), quantifying trends in biodiversity, to monitor environmental he...

The complexity of mathematical models of ecological dynamics varies greatly, and it is often difficult to judge what would be the optimal level of complexity in a particular case. Here we compare the parameter estimates, model fits, and predictive abilities of two models of metapopulation dynamics: a detailed individual-based model (IBM) and a popu...

Evolution of dispersal is affected by context-specific costs and benefits. One example is sex-biased dispersal in mammals and birds. While many such patterns have been described, the underlying mechanisms are poorly understood. Here, we study genetic and phenotypic traits that affect butterfly flight capacity and examine how these traits are relate...

The role of competition in structuring communities of herbivorous insects is still debated. Despite this, few studies have simultaneously investigated the strength of various forms of competition and their effect on community composition. In this study, we examine the extent to which different types of competition will affect the presence and abund...

Herbivores usually consume a mere fraction of available plant biomass. Spatial patterns in feeding damage may be attributable to induced defences by the host plant; a damaged plant reacts by lowering its nutritional value, thereby forcing herbivores to move on before food gets worse. In this study, we test this general hypothesis on a specific mode...

One of the most difficult problems in developing spatially explicit models of population dynamics is the validation and parameterization of the movement process. We show how movement models derived from capture–recapture analysis can be improved by incorporating them into a spatially explicit metapopulation model that is fitted to a time series of...