Grayling migration in large Norwegian rivers

Shorebird fieldwork Alaska

Past and present fieldwork 

  • Fish movement and foraging ecology
    • with Dr. E.S. Bakker (Netherlands Institute of Ecology)
    • We study fish movements, reproduction, foraging and habitat selection of the key species in lake Markermeer, in relation to the construction of new islands "the Marker Wadden" in this lake. How do the fish and the rest of the food web respond to the construction of these islands with sheltered, shallow, and warm waters? What are potential effects on the fish populations and community in the lake?
  • Dispersal of seeds and aquatic invertebrates by piscivorous birds
    • with Prof. A.J. Green (Doñana Biological Station, Sevilla, Spain)
    • We sampled pellets regurgitated by great cormorants to investigate their potential to secondarily disperse plant seeds and aquatic invertebrates fist ingested by fish. Read more in Biology Letters.
  • Grayling migration ecology in large Norwegian rivers
    • with Prof. A. Vøllestad (UiO, Oslo, Norway) & Dr. J. Museth (NINA, Lillehammer, Norway).
    • We set up a large scale field experiment to determine to what extent small European grayling (Thymallus thymallus) larvae (< 20 mm) may drift downstream due to high discharges in large river systems. Voluntary or involuntary downstream drift may be an important driving factor for adult upstream spawning migration. Read more in Journal of Fish Biology
  • Seed dispersal by Song Thrushes (Turdus philomelos), Balearctic Islands, Spain
    • with Dr. L. Santamaría (IMEDEA, Spain).
    • We monitored seed removal by Thrushes over time, to make a spatially explicit model of seed predation and subsequent endozoochorous seed dispersal in a remote small island system.   
  • Shorebird migration ecology, Australia
    • with Prof. M. Klaassen (Deakin University, Australia).
    • We captured, measured and banded migratory shorebirds to retrieve geolocators containing information on migration. 
  • Population genetics of aquatic snails, Parque Nacional de Doñana, Spain
    • with Dr. J. Figuerola (Doñana Biological Station, Sevilla, Spain).
    • We sampled the invasive aquatic snail Physa acuta throughout and around Doñana National Park, in order to perform population genetic analyses that informed on the potential dispersal vectors used by this invasive species. Read more in Freshwater Biology 
  • Breeding ecology Brentgeese (Branta bernicla), Taimyr, Siberia
    • with Yu. L. Mazurov (Heritage institute, Russia), Dr. B.S. Ebbinge (Alterra, The Netherlands), Dr. B.A. Nolet (NIOO, The Netherlands).
    • Within a long term monitoring framework we investigated the breeding succes and choices of Arctic breeding Brentgeese (Branta bernicla) in relation to lemming cycles and the presence of gulls and snowy owls on the breeding sites.
  • Shorebird breeding ecology, Yukon-Kuskokwim Delta, Alaska, US
    • with Dr. S.E. Jamieson (Simon Fraser University, Canada), B. McCaffery (U.S. Fish & Wildlife Service, US).
    • By catching, color banding and following individual Dunlin (Calidris alpina pacifica) we could determine how individuals make decisions on mate choice and choice of nesting sites when arriving to Arctic breeding grounds after their long-distance migration. Read more in The Wilson Journal of Ornithology

Seed dispersal by Song Thrushes

Fieldwork Doñana National Park, Spain