Do Zebra Finches avoid feeding locations used by sick birds?

Abstract

Pathogens play a key role in population dynamics. A number of species avoid the increased risks of infection inherent to group living by avoiding individuals they know to be sick. It would seem that individuals would experience similar fitness benefits by avoiding sharing resources with individuals that they know to be sick. By avoiding these resources, they avoid a possible source of infection. Despite these apparent benefits, a recent study has shown that male House Finches preferentially feed near sick, rather than healthy, conspecifics. There are a number of immunological and social tolls that occur when male finches lose in aggressive interactions, incentivizing the birds to feed near individuals that they perceive to be weaker. In this study we investigated the preference, in the absence of competition, of Zebra Finches for food resources used by a healthy neighbor and a neighbor showing symptoms of infection. We found that, when allowed to feed in the absence of costly social competitions, Zebra Finches appear to select resources at random, despite having observed sick conspecifics using these same food resources.