What would happen if an adorable 3-day old gosling was placed between two wire enclosures, one containing a sibling, and one containing a same-age gosling from another clutch? Would the baby bird recognize its brother or sister and patter over to its relative?
The answer: yes… at least as often as dentists recommend sugarless gum*. In four out of five trials, the little puffball sidled up to its sibling rather than a stranger’s young’un.
There’s one catch. The youngest goslings (ages 3–9 days) prefer groups. Even if it’s a group of unfamiliar goslings, the little bird almost always waddled over to an unknown group rather than a single relative. By 15 days old though, the youngsters reliably reunite with their kin, no matter how small their family.
p.s. I created this image at an awesome carbon dust workshop, coordinated by GNSI-Carolinas, this weekend. Marlene Hill Donnelly from the Chicago Field Museum was our fearless instructor – she’s wonderful!
*Radesäter, T. 1976. Individual sibling recognition in juvenile Canada geese (Branta canadensis). Canadian Journal of Zoology, 54(7): 1069–1072