Marjolijn Christianen

Our new paper that just came out today in Marine Biology research suggests so: Press release by Bureau Waardenburg/WUR: Underwater discovery oyster bed reveals native oyster mysteries The flat oyster, an iconic species that once covered 20.000 square kilometres of the Dutch North Sea bed and then disappeared, was rediscovered in 2016 in the Voordelta. [...]

A new paper by lead author Alan Rees and collegues reviews how we can use drones and other UAVs in sea turtle research and conservation. Here we review the diverse ways in which incorporating inexpensive UAVs may reduce costs and field time while improving safety and data quality and quantity over existing methods for studies [...]

Today our new paper came out in Frontiers of Marine Science. Emerging from the 12th International Seagrass Biology Workshop, held in October 2016, has been the view that grazing marine megafauna may play a useful role in helping to identify previously unknown seagrass habitats. Here we describe this concept, showing how detailed information on the distribution [...]

Today was my first day at the Aquatic Ecology and Water Quality Management group at Wageningen University. This is the official start of my NWO-VENI grant “Global defaunation and plant invasion: cascading effects on seagrass ecosystem services”. Looking forward to work here and expand my research (network)! More on this new research soon!     [...]

What fuels the Wadden Sea food web? This is the question that we addressed  in one of the largest ecological research projects in the Netherlands, the recently finalized “Waddensleutels” program. The answer is surprising, and has been published last month in Ecology. “Benthic primary producers are the solar panels that fuel the Wadden Sea food web” [...]

Seagrasses are often the “ungly duckling” in marine conservation, and receive disproportionally little attention in the media and in scientific studies when compared to mangroves and coral reefs. However, seagrasses are essential components of coastal zones due to their extremely high productivity and the high biodiversity they support. So time for more research! Inside Lac [...]

Our in-water survey of sea turtles and their habitats in St. Eustatius (a.k.a. “Statia”) was very successful. We aimed to collect data to analyse the habitat use and population connectivity of green and hawksbill turtles as part of a larger NWO research program encompassing the 6 Dutch Caribbean Islands. Together with STENAPA (National Park authority of St Eustatius) and volunteers, and support [...]

During our fieldwork on St. Eustatius. Laurent helped as a volunteer to catch turtles. He also made some really nice video footage while free diving. His guest post: “Being a volunteer in a scientific mission is very simple : You just have to listen to the Project Leader, and you have to be available anytime, [...]

Sea turtle sex is not determined at the time of fertilization like in humans, it is set by the temperature level during nest incubation. Recently for some small island rookeries througout the Caribbean researchers reported a shift towards a more female dominated hatchlings/populations as nest temperatures slightly increased in these areas (warmer beaches result in female turtles). At St. [...]

Lisa Becking (Wageningen University and IMARES) and I, together with Sea Turtle Conservation Bonaire (STCB) ; Mabel Nava, Sue Willis and Robert van Dam have shown in a recent publication that sea turtles who breed in Bonaire, Caribbean Netherlands, migrate great distances of up to 3500km to reach their foraging grounds across the Caribbean in 10 different countries. [...]

Bon dia! My name is Moniek and as an Ecology and Evolution student at the University of Groningen I have been doing fieldwork on Bonaire for my MSc internship. Most importantly I have been continuing the turtle exclusion experiment in Lac Bay; going out with a kayak and diving gear to measure and/or clean at [...]

Today 2 papers of our group were published online! This papers are the result of a successful collaboration between the University of Groningen, NIOZ and Radboud University, The Netherlands The first study by Els van der Zee et al. demonstrates that food web structure and complexity can be fundamentally shaped by habitat-modifying species.  This works through facilitation rather than trophic interactions [...]

Within the Dutch Caribbean, green and hawksbill turtle rookeries and foraging grounds are found. Green and hawksbill turtles have been decimated by human exploitation and habitat degradation, calling for knowledge of population structure and demographic history. Here we investigate migration patterns in these highly migratory species and evaluate current population status. In other words: How many turtles were there [...]

You can download my PhD thesis “Seagrass systems under nutrient loads, hydrodynamics and green turtle grazing – Do turtles rule the seagrass world?” here (pdf 88 MB). And the papers of my thesis here. Next friday I will defend my PhD thesis at Radboud University Nijmegen. I still have some paper copies left. So send me [...]