2.1 Image datasets
To examine whether the performance of feature-based image matching software packages varies for different populations of African wild dogs, we considered image catalogues from two wild dog populations, one that spans Laikipia, Samburu, and Isiolo Counties in Kenya (37°2′E, 0°6′N) and another from the Savé Valley Conservancy in Zimbabwe (32°4’E, 20°3’S). The Kenyan dataset contained images taken between 2004 and 2017 (n = 9139), and the Zimbabwean dataset contained images taken between 2010 and 2013 (n = 2066). In Kenya, these images were taken with ten different cameras (Olympus© C765UZ, Canon© PowerShot A720IS, EOS Digital Rebel XT, 10D, 40D, and 60D, Fujifilm© FinePix S5500, Kodak© Easyshare Z1015IS, Nikon© D70s, and Nikon© Coolpix90). In Zimbabwe, they were taken with five different cameras (Canon© EOS 450D, 20D, and Digital Rebel XT, and Panasonic© DMC-FZ20, and Zoran© Coach). Both datasets were collected as part of long-term monitoring programmes, and contained images of both single wild dogs and groups of wild dogs, ranging in their posture from lying down to walking.