Table 1 Individual identification methods
From: LemurFaceID: a face recognition system to facilitate individual identification of lemurs
Method | Advantages | Disadvantages |
|---|---|---|
Tagging/Collaring | Systematic across studies; opportunities to collect data that require animal to be in hand; precise location of animal known at all times (using GPS collar) | Invasive; poses risks to animals; expensive; less feasible for studies requiring large sample sizes; individual IDs may be unknown with loss of tag/collar |
Manual identification based on physical variation | Non-invasive, low cost | Substantial training required; IDs may differ across studies/researchers; prone to intra- and inter-observer error; time-consuming for large sample sizes when individuals are not recognized instantly (e.g., manual comparisons of photographs are required) |
Face recognition | Systematic across studies; non-invasive; minimal user training; reduces time to make identifications when datasets are large allowing for increased sample size/scale | Requires large dataset for development; currently requires partial knowledge of individual IDs; individual IDs may be unknown to the researcher if the system is unavailable for use |