Proximity to humans affects local social structure in a giraffe metapopulation

Female giraffes' social boundaries can exist without fences between them. Animals using overlapping stretches of the same landscape repeatedly associated with different sets of females. Their groups split and reformed, but beneath that daily turnover were recognisable communities. The researchers then asked whether living close to people was associated with changes inside those communities.

Monica Bond, Barbara König and colleagues photographed adult female Masai giraffes in Tanzania's Tarangire ecosystem between 2011 and 2016. From 1,139 identified females, they built a network using 540 seen at least six times. They detected 14 communities and compared 11 with sufficient membership, examining how often females appeared together alongside vegetation, giraffe density and distance from human settlements.

Communities nearer traditional pastoralist homesteads had weaker relationships on average, with associations concentrated more unevenly among particular companions. Distance to towns did not show the same relationship. Repeated disturbance or changes in food availability could help explain the pattern, but the study did not experimentally separate those causes. The discovery is therefore both social and spatial: sharing habitat does not mean sharing one society, and human proximity can coincide with changes that a simple giraffe count would never reveal.