I am a behavioural ecologist with a passion for birds and marine ecosystems. I’m fascinated with understanding why individuals behave the way they do. Known causes of intraspecific variation in behaviour include previous exposure to varying environmental factors and differences in internal state (both the physiologically and psychological state). Understanding an individual’s motivation to act may play a key role in predicting a species response to change.
My research primarily focusses on unraveling causes and consequences of consistent among-individual variation in migratory behaviour in Red Knots (Calidris canutus). Red knots are shorebirds that annually migrate between their arctic breeding grounds and their southern intertidal wintering areas. A major axis of my research is focused on understanding intraspecific variation of their migratory routines. I am especially interested in the role of experience (= a developmental cognitive process) in shaping individual variation in behaviour. Because, understanding the influence of experience in the shaping individual migratory routines may play a key role in predicting the species response to Global Change. To unravel underlying mechanisms leading to individual variation in behaviour I combine experimental work, field observation and satellite tracking of individuals.
Postdoc: ‘Phenological and behavioural responses to climate change in migratory shorebirds’
In my current postdoc project, I joined Jan van Gils and his team to investigate how global warming affects red knots from their Arctic breeding grounds to their tropical wintering areas and back.
All too briefly: Due to global warming, which is especially strong at higher latitudes, the Arctic summer has advanced by almost a month in the past decades. As a result, the emergence of insects (the main prey for red knot chicks) has also advanced and this seems to induce a so-called ‘tropic mismatch’, with red knot chicks growing up after the peak food supply. Read more about this VICI-funded project.
Within this project I focus on unraveling potential ways red knots can mitigate the effects of an Arctic-warming-induced trophic mismatch, with special attention to migration. The most straightforward way to deal with the advanced Arctic phenology for red knots is to advance northward migration. To investigate this possibility, we will focus on the timing of key events during migration (i.e., onset of fueling, departure from wintering and staging sites and arrival at the breeding grounds) and how these are influenced by current changes in climate.
(1) More specifically, we will set up a field experiment in which we manipulate timing of spring migration to investigate the potential constraints which limit advancements in migration. We will manipulate the fuel deposition rates of two groups of individuals (slow, fast) to assess whether timing and duration of stops is flexible, and indeed limited by fueling rate. By means of satellite tracking of the manipulated individuals, and in comparison, with an unmanipulated control group equipped with transmitters, we will be able to pinpoint exactly at what point during migration individuals are most constrained.
(2) Plastic responses to climate may be constrained by inherited circannual rhythms. Consequently, potential mechanism for keeping pace with shifting phenology may require evolutionary adjustments. I will use a large dataset that contains weekly measurements of body mass and plumage to assess changes in onset of fueling and moult over the past 30 years.
(3) Coming back to the role of experience in the shaping individual routines I will investigate potential downstream effects of the tropic mismatch on intraspecific variation in behaviour. To this extend I will relate food conditions experienced during early development to variation in foraging behaviour at a later age.
[image cover thesis]
I recently received my PhD from the University of Groningen. The aim of my thesis ('Why Knot? Exploration of Variation in Long-Distance Migration) was to increase understanding of the development of individual migratory routines. To that extend I first explored individual variation in migratory behaviour present in wild red knots (Calidris canutus) using a novel solar-powered satellite transmitter. Second, I investigated how differences in experience effect the development of physiological and behavioural traits in birds temporarily held in captivity. By combining these results I show that environmental conditions play a key role in shaping individual migratory routines.
2020-current: Postdoctoral researcher at NIOZ
2014-2020: PhD student at NIOZ and University of Groningen (click here for more information).
Please find my complete list of NIOZ-publications at the bottom of this webpage. You can also find all my publications on Research Gate.
2016: Poster Price at the International Wader Study Group conference in Cork, Ireland
2020: Bioscoop film Silence of the Tides
2018: De Eilanden Het Wad, met Midas Dekkers
2018: Tracking Red Knots in the East Asian - Australasian Flyway in NW Australia