Wildlife photo-identification

{{short description|Animal tracking method}}

File:Humpback whale flukes variation.png flukes to identify and track the animals]]

Photo-identification is a technique used to identify and track individuals of a wild animal study population over time. It relies on capturing photographs of distinctive characteristics such as skin or pelage patterns or scars from the animal. In cetaceans, the dorsal fin area and tail flukes are commonly used.

Photo-identification is generally used as an alternative to other, invasive methods of tagging that require attaching a device to each individual. The technique enables precise counting, rather than rough estimation, of the number of animals in a population. It also allows researchers to perform longitudinal studies of individuals over many years, yielding data about the lifecycle, lifespan, migration patterns, and social relationships of the animals.

Species that are studied using photo-identification techniques include:

• Killer whales
• Humpback whales
• Whale sharks[http://www.whaleshark.org/ ECOCEAN Whale Shark Photo-identification Library]
• Manta rays[http://www.mantas.org/ The Manta Network] - see Manta Matcher
• Octopuses (Wunderpus photogenicus)[http://calphotos.berkeley.edu/Wunderpix.html Wunderpix Photo ID project]
• Salamanders{{Cite journal |last1=Gamble |first1=Lloyd |last2=Ravela |first2=Sai |last3=McGarigal |first3=Kevin |date=2007-08-29 |title=Multi-scale features for identifying individuals in large biological databases: an application of pattern recognition technology to the marbled salamander Ambystoma opacum: Identifying individual marbled salamanders |journal=Journal of Applied Ecology |language=en |volume=45 |issue=1 |pages=170–180 |doi=10.1111/j.1365-2664.2007.01368.x|doi-access=free }}
• Giraffes{{Cite journal |last1=Lee |first1=Derek E. |last2=Lohay |first2=George G. |last3=Cavener |first3=Douglas R. |last4=Bond |first4=Monica L. |date=2022-09-06 |title=Using spot pattern recognition to examine population biology, evolutionary ecology, sociality, and movements of giraffes: a 70-year retrospective |url=https://doi.org/10.1007/s42991-022-00261-3 |journal=Mammalian Biology |volume=102 |issue=4 |pages=1055–1071 |language=en |doi=10.1007/s42991-022-00261-3 |s2cid=252149865 |issn=1618-1476}}