Royal Netherlands Institute for Sea Research

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Research interests

My research has focussed on three main themes: Marine mammals, fish & fisheries, and statistical ecology.

Over the years, I have studied several marine mammal species (e.g. harbour and grey seal, harbour porpoise and stellar sea lion). I have a strong interest in solving challenging statistical ecological problems and for example worked on spatial point process models, state-space models for animal movement, distance sampling, Bayesian population models, and statistical models for species distributions.

Currently my research focusses on understanding the spatial distribution of marine mammals. In the coming years, I hope to spend more time studying how the formation of colonies on land is shaped by the surrounding resource landscape. Although most organisms (including humans) have a natural tendency to aggregate because of group benefits, it often leads to increased food competition and local resource depletion. If resource availability declines, it may cause a sudden population collapse or even species extinction. The fact that animal aggregations or human settlements of different sizes occur within a landscape indeed suggests the existence of a balance between group benefits and spatially-varying resource availability. There is however an gap in understanding of how resource availability effects the size and distribution of such settlements. Hence, our ability to predict whether those aggregating species are able to cope with ongoing environmental changes is limited.



From 2018: Postdoc at NIOZ (0.5 FTE, NWO Arctic TopSector Water)

From 2018: Lecturer/assistant professor at Wageningen University (0.2 FTE)

From 2007: Researcher Wageningen Marine Research (0.3-1 FTE) 2011-2015: Postdoc at IMARES/Wageningen University (0.75 FTE, NWO-ZKO program effect of sound on marine mammals)

2009-2011: Postdoc at NIOZ (0.4 FTE). 2006-2007: Lecturer at Biometris, Department of Mathematics and Statistics, Wageningen University

2003-2007: PhD at Sea Mammal Research Unit, St Andrews University, Scotland

2002-2003: Biometrician at Alterra, Texel.


Professional education

2003-2007: PhD at Sea Mammal Research Unit (SMRU), St Andrews University, Scotland

2001-2002: MSc animal ecology at Wageningen University, with thesis/traineeships at SMRU (Scotland), Alaska Department of Fish and Game (Alaska, USA) and NIOZ

1997-2001: BSc Biology at Wageningen University with a specialization in ecology, and BSc Marine biology program at State University Groningen.



Aarts, G., Brasseur, S., Poos, J.J., Schop, J., Kirkwood, R., van Kooten, T., Mul, E., Reijnders, P., Rijnsdorp, A.D., Tulp, I. (2019). Top‐down pressure on a coastal ecosystem by harbor seals. Ecosphere 10(1): e02538.

Aarts, G., Fieberg, J., Matthiopoulos, J. (2012) Comparative interpretation of count, presence-absence and point methods for species distribution models. Methods in Ecology and Evolution 3: 177–187.

Aarts, G., MacKenzie, M., McConnell, B., Fedak, M., Matthiopoulos, J. (2008) Estimating space-use and habitat preference from wildlife telemetry data. Ecography 31: 140–160.

Aarts, G., Fieberg, J., Brasseur, S.M.J.M., Matthiopoulos, J. (2013) Quantifying the effect of habitat availability on species distributions. Journal of Animal Ecology , 82: 1135–1145.

Warton, D., Aarts, G. (2013) Advancing our thinking in presence-only and used-available analysis. Journal of Animal Ecology 82: 1125–1134.

Please find my list of publications at the bottom of this webpage or on Google Scholar

You can download all my publications on ResearchGate


Awards and Prizes

2018: NWO Arctic TopSector Water