Leo obtained his PhD entitled "Search, settle, reside & resign: territory acquisition in the (Eurasian) Oystercatcher" at the University of Groningen in 2004 (Supervised by Rudi Drent). His PhD focussed on floaters, mature birds struggling to find a vacant breeding slot in the population. His research was one of the first to show experimentally that being familiar with a site is a crucial prerequisite for successful settlement (Behav. Ecol. 15: 278-285). Besides that, he studied intensively the cost and benefits of divorce in this species (Anim. Behav. 66: 178-184) and the effects of raising conditions on future settelement (in press).

Before starting his Phd, Leo spent some time working at Alterra Green World research in the Netherlands, conducting a survey on the effects of human disturbance on waders, and doing offshore field work (counting seaducks and performing pelagic benthos sampling). He also spent one summer at the Taymyr Peninsula, Siberia, studying the breeding biology and breeding energetics of Little Stints and Curlew sandpipers. His masters projects were all carried out at the University of Groningen, with field work on Svalbard (experimental manipulation of brood size in Barnacle geese, J. Anim. Ecol. 68: 753-768), laboratory work on the cost of locomotion in waders (training knots and turnstones to run a treadmill, Ibis 140: 323-328, Ardea 87: 199-205) and field work in Langebaan Lagoon (together with Theunis Piersma, Les Underhill and Popko Wiersma). The project in Langebaan was focussed on Basal Metabolic Rates of Afro-eurasian migrant waders and was very successful: resulting in two often cited papers in Ardea (86: 71-80) and Physiological Zoology (69: 191-217) and a wonderful field trip.

After his PhD, Leo got a position as ecologist at Altenburg & Wymenga ecological consultants in the Netherlands (www.Altwym.nl), where he was mainly involved in the acquisition of new projects and carrying out various projects often with respect to EU legislation. This ecological consultancy is carrying out ecological research in eastern Europe, The Netherlands and in Sahelian Africa (currently focus on Mali and Senegal). Last February he made a short assessment of the biodiversity value of Typha vegetation of the Senegal river (together with Wetlands International Dakar) in Mauretania and Senegal.

His post-doc research at the ADU will be focussed on Terns, and especially on the migration system of Sandwich Terns. Central in his studies will be the use of stable isotopes to investigate migratory connectivity and trophic relations.