The two oxpecker species reveal the role of movement rates and foraging intensity in species coexistence

The two Buphagus oxpecker species are specialized passerines that forage for ticks and other food particles on the body of ungulates in the African savannas. One of their intriguing features is their ability to coexist despite sharing the same, specialized diet. Using co-occurrence data (photographs of giraffes with oxpeckers on them) and Approximate Bayesian Computing, we demonstrate that yellow-billed oxpeckers changed host faster than red-billed oxpeckers and appeared to displace red-billed oxpeckers from preferred giraffe body parts. Conversely, red-billed oxpeckers exhibited a fuller use of each host and displaced yellow-billed oxpeckers from distal giraffe body parts. These findings highlight that the partition of giraffe hosts in two separate niches was only part of the coexistence story in this species pair. More precisely, the oxpeckers shared resource by exploiting it at different rates. They engaged in different trade-offs between giving-up density, patch discovery rate, and ...