Cherine Jantzen

Cherine Jantzen

PhD Candidate

Bezoekadres

Droevendaalsesteeg 10
6708 PB Wageningen

+31 (0) 317 47 34 00

The Netherlands

Netwerk

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Aiming to understand the heartbeat of the forest - how is beechnut production affecting populations of mice, marten, wild boar and other species in the forest?

Biografie

Background

During my studies, I was first focussing on behavioural biology working with primates, switching to nature conservation and ecology in my masters to finally write my master's thesis about phenology  and selection on reproductive timing of great tits and blue tits. For my PhD, I shifted my focus once more to now study seed production of trees and interaction networks in Dutch forests. 

My PhD project

The annual production of beechnuts, the seeds of European beech (Fagus sylvatica), is highly variable across years and provides a valuable food resource for a variety of species. In my PhD project, I am looking at the beech seeding patterns in the Veluwe, Netherlands and aim to understand how fluctuations in seed availability influence the population dynamics of the species that are relying on the beechnuts. For this, I am looking at the broader interaction network of forest species that are directly or indirectly affected by the seeding patterns.

Since beech seeding is sensitive to climate change, I further want to understand how future climate change will affect the beech seeding dynamics and forecast how these effects will cascade through the species network. 

Other work

In my previous role at NIOO as a FAIR data analyst, I was involved in making different ecological datasets FAIR (Findable, Accessible, Interoperable, Reusable) and use this experince to write a hands-on guide for ecologists to make their own data more FAIR. 

Onderzoeksgroepen

CV

Employment

  • 2024–Present
    PhD Candidate at NIOO-KNAW
  • 2023–2024
    FAIR data analyst at NIOO-KNAW

Education

  • 2020–2023
    MSc Biodiversity, Ecology and Evolution - Georg-August University Göttingen
  • 2017–2020
    BSc Biology - Georg-August University Göttingen

Publicaties

Peer-reviewed publicaties

  • Ecology and Evolution
    06-2026

    Masting Breakdown in European Beech Reduces Fitness Benefits of Masting, Partly Explained by Climate Change

    Masting, highly synchronised but temporally variable seed production, is initiated by weather cues and is thus highly sensitive to climate change. Changes in these cues can lead to a masting breakdown, reducing the fitness benefits of masting through decreasing pollination efficiency and increasing predation risk for seeds. Here, we use 50 years of individual tree data on annual seed production of European beech (Fagus sylvatica) in the Netherlands to assess temporal changes in masting patterns and their consequences for the selective benefits of masting. Additionally, we use a novel approach to identify which weather cues initiate reproduction, assess their temporal changes, and test whether they account for the observed changes in masting. We show that synchrony and inter-annual variation in beechnut production have declined, resulting in a masting breakdown in the late-2000s, since which there has been constant, but low, seed production each year. Consequently, predation risk increased almost three-fold, while pollination became less efficient, together reducing the fitness benefits of masting. Seed production was driven by precipitation and temperatures in the year of seed fall and the two preceding years, but the periods within the year in which trees respond to each climate variable differ in both timing and duration. Interestingly, only temperature, not precipitation, has changed over time, but this change only partly explained the observed changes in masting patterns. Masting breakdown is shown across the species range, but its fitness consequences remain understudied, because detailed, individual-level, long-term data are required but still rare. By using such a dataset, we here provide crucial evidence for the negative consequences of masting breakdown for beeches through reduced pollination efficiency and increasing predation risk. Using a new methodology, we further underline the strong effects of weather cues on reproduction, while showing that changing climate alone cannot be driving the masting breakdown and must interact with currently unidentified factors.

    https://doi.org/10.1002/ece3.73809
  • Ecological Informatics
    19-03-2026

    Putting FAIR into practice for ecologists

    Cherine Jantzen, Stefan Vriend

    Ecological data is highly diverse due to the complex nature of the systems they describe. Proper documentation and management are often lacking or not designed for data reuse by others, making the data difficult to find, understand, and at risk to be lost. Adopting the FAIR (Findable, Accessible, Interoperable, Reusable) principles into data practices is a way to mitigate these problems. However, the FAIR principles are abstract and not easily understood by domain scientists. Despite a growing body of assessment tools and resources about FAIR, applying it in practice remains challenging as clear implementation guidelines are missing. We aim to fill this gap by translating the FAIR principles into four data components (metadata, storage, standard and structure) that can be successively worked on to enhance the FAIRness and structure of data and provide a general workflow together with a hands-on guide to give practical suggestions on how to improve the reusability of ecological data. For every workflow step, we introduce the rationale behind it and point towards implementation solutions tailored to ecology. Additionally, we introduce an evaluation tool that facilitates the entry to this workflow by guiding to only those steps that are necessary for the evaluated dataset. With the workflow, guide and tool introduced here, we lower the threshold for ecologists to start making ecological data FAIR, which will ensure long-term reusability of valuable data sources.

    https://doi.org/10.1016/j.ecoinf.2026.103712
  • Proceedings of the Royal Society B: Biological Sciences
    18-10-2023

    Climate change does not equally affect temporal patterns of natural selection on reproductive timing across populations in two songbird species

    Climate change has led to changes in the strength of directional selection on seasonal timing. Understanding the causes and consequences of these changes is crucial to predict the impact of climate change. But are observed patterns in one population generalizable to others, and can spatial variation in selection be explained by environmental variation among populations? We used long-term data (1955–2022) on blue and great tits co-occurring in four locations across the Netherlands to assess inter-population variation in temporal patterns of selection on laying date. To analyse selection, we combine reproduction and adult survival into a joined fitness measure. We found distinct spatial variation in temporal patterns of selection which overall acted towards earlier laying, and which was due to selection through reproduction rather than through survival. The underlying relationships between temperature, bird and caterpillar phenology were however the same across populations, and the spatial variation in selection patterns is thus caused by spatial variation in the temperatures and other habitat characteristics to which birds and caterpillars respond. This underlines that climate change is not necessarily equally affecting populations, but that we can understand this spatial variation, which enables us to predict climate change effects on selection for other populations.
    https://doi.org/10.1098/rspb.2023.1474

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