First rangewide density estimate of the endemic and isolated Luangwa giraffe in Zambia

Some Luangwa giraffes were living beyond the edge of their mapped range. This isolated form of Masai giraffe lives only in Zambia’s Luangwa Valley, so overlooking part of its distribution means overlooking part of the entire population. Earlier surveys concentrated on its better-known core, while sightings farther south suggested that the published map was incomplete.

Catherine Sun, Frederike Otten and colleagues drove photographic surveys between August and November 2023, extending their search 120 kilometres south of that mapped boundary. They identified giraffes from their individual coat patterns and analysed 439 encounters with 277 adults and subadults. Repeated sightings fed a model that accounted for uneven search effort and animals missed by observers; calves were excluded because their movements were not independent of adults.

The team identified 55 giraffes beyond the old southern boundary. Across the study area, the model estimated 760 adults and subadults, with a credible range of 651–890. That larger total does not demonstrate population growth: the survey covered more ground and used different methods. Giraffes were concentrated near permanent rivers, including in moderately human-modified areas. The discovery changes where conservation needs to look, not simply how many giraffes it should expect to find.