title: Photos provide information on age, but not kinship, of Andean bear.
abstract: Using photos of captive Andean bears of known age and pedigree, and photos of wild Andean bear cubs <6 months old, we evaluated the degree to which visual information may be used to estimate bears' ages and assess their kinship. We demonstrate that the ages of Andean bear cubs ≤6 months old may be estimated from their size relative to their mothers with an average error of <0.01 ± 13.2 days (SD; n = 14), and that ages of adults ≥10 years old may be estimated from the proportion of their nose that is pink with an average error of <0.01 ± 3.5 years (n = 41). We also show that similarity among the bears' natural markings, as perceived by humans, is not associated with pedigree kinship among the bears (R (2) < 0.001, N = 1,043, p = 0.499). Thus, researchers may use photos of wild Andean bears to estimate the ages of young cubs and older adults, but not to infer their kinship. Given that camera trap photos are one of the most readily available sources of information on large cryptic mammals, we suggest that similar methods be tested for use in other poorly understood species.
authors.affiliation: Institute for Conservation Research, San Diego Zoo Global , San Diego, CA , USA.
authors.forename: Russell C
authors.initials: RC
authors.lastname: Van Horn
authors.affiliation: Nelson Institute for Environmental Studies, University of Wisconsin-Madison , WI , USA.
authors.forename: Becky
authors.initials: B
authors.lastname: Zug
authors.affiliation: Department of Forest and Conservation Sciences, University of British Columbia , BC , Canada ; Spectacled Bear Conservation Society , Squamish, BC , Canada.
authors.forename: Robyn D
authors.initials: RD
authors.lastname: Appleton
authors.affiliation: Centro de Biodiversidad y Genética, Universidad Mayor de San Simon , Cochabamba , Bolivia.
authors.forename: Ximena
authors.initials: X
authors.lastname: Velez-Liendo
authors.affiliation: Durrell Institute of Conservation and Ecology, University of Kent , Canterbury, Kent , UK.
authors.forename: Susanna
authors.initials: S
authors.lastname: Paisley
authors.affiliation: Institute for Conservation Research, San Diego Zoo Global , San Diego, CA , USA.
authors.forename: Corrin
authors.initials: C
authors.lastname: LaCombe
keywords: Age estimation; Andean bear; Camera traps; Kinship; Natural markings; Noninvasive; Spectacled bear; Tremarctos ornatus