Broeden in een veranderende arctis: fysiologie en gedrag van Brandganzen
|PhD ceremony:||M.E. (Margje) De Jong|
|When:||September 23, 2021|
|Supervisor:||prof. dr. P.D. (Peter) Jordan|
|Co-supervisor:||dr. M.J.J.E. (Maarten J J E) Loonen|
|Where:||Academy building RUG|
This dissertation combines four years of research and long-term data to gain insight into how Arctic-breeding barnacle geese (Branta leucopsis) cope with changes in their environment. I focused on the little-known effects of a nest parasite on goose behaviour and breeding success, altered timing of goose reproduction with climate warming, effects of exposure to contaminants from a historic coal mine area on gosling physiology and behaviour, and the potential for goose behavioural change.The main insights are: • Nest fleas (Ceratophyllus vagabundus vagabundus) are strikingly present in a barnacle goose colony on Svalbard and we found a negative association between nest flea numbers and goose reproductive success. However, this finding could not be explained by the negative effects of fleas on female behaviour during incubation. • Barnacle geese in the high and low Arctic showed a similar advancement in the timing of egg laying with earlier springs, but they did not fully compensate for the advancement in snowmelt. High-Arctic geese might be especially vulnerable to the negative effects of climate warming, as their advancement in reproduction seems inadequate to reach the optimal level of reproductive success associated with earlier laying dates. • Exposure to contaminants from a historic coal mine increased mercury levels in gosling livers, but there were no strong neurotoxic effects, nor strong negative effects on immune system parameters or plasma corticosterone levels. Grazing in a historic coal mine changed stress-related behaviours and corticosterone metabolite levels measured in faeces. • The nest defense behaviour of female barnacle geese differed consistently between individuals, but increased during the breeding season and with the age of the geese.