Science - November 19, 2009

No two geese are the same

Geese have personalities. And their personalities influence how they forage. Ralf Kurvers of the Resource Ecology Group has demonstrated this.

What's good for the goose is not necessarily good for the gander - or even for another goose. Sounds obvious but it isn't. 'We always assume that every animal has the same choices. In models simulating how animals spread out over a landscape it is always assumed that they are all the same. But I haven't found any evidence for that', says biology PhD researcher Kurvers.
To the contrary in fact: Personality plays a role. This has emerged from tests with barnacle geese that Kurvers has been doing at the NIOO in Heteren. In this context, personality means a goose displaying consistent behaviour. Kurvers focuses on the variation between individuals and the way the geese gather information. In short: whether they go out looking themselves or whether they wait and see. Geese that go out looking for themselves are bold, those that wait and see are shy.
Boldness scale
Kurvers bases this typology on observations of how a goose approaches an unfamiliar object in an isolated room.  A boldness scale emerges. This personality trait appears to play a role in feeding trials too. Bold geese are the first to reach the feeding place. That sounds logical. But what is more interesting is what happens when you get geese foraging in pairs. 'A goose with a bold mate arrives earlier than one with a shy mate. So it also depends who the goose is with.' A shy goose holds his bolder companion back.
Kurvers' tests show irrefutably that the personality of a barnacle goose determines the role it plays during foraging. Shy geese prefer to follow their bolder fellows. And that is new.
It is not for nothing that Kurvers picked the barnacle goose as his subject. Figuring out the psyche of the goose could be important for tackling the goose overpopulation problem in the Netherlands. The government wants to keep geese is specially designated areas. But in practice that meets with only moderate success. 'So you could train 'bold' geese to go to these areas.' On the assumption that the rest would follow. 'But that is speculative', Kurvers quickly adds.