Antarctic skuas recognize individual humans
Recent findings report that wild animals can recognize individual humans. To explain how the animals distinguish humans, two hypotheses are proposed. The high cognitive abilities hypothesis implies that pre-existing high intelligence enabled animals to acquire such abilities. The pre-exposure to stimuli hypothesis suggests that frequent encounters with humans promote the acquisition of discriminatory abilities in these species. Here, we examine individual human recognition abilities in a wild Antarctic species, the brown skua (Stercorarius antarcticus), which lives away from typical human settlements and was only recently exposed to humans due to activities at Antarctic stations. We found that, as nest visits were repeated, the skua parents responded at further distances and were more likely to attack the nest intruder. Also, we demonstrated that seven out of seven breeding pairs of skuas selectively responded to a human nest intruder with aggression and ignored a neutral human who had not previously approached the nest. The results indicate that Antarctic skuas, a species that typically inhabited in human-free areas, are able to recognize individual humans who disturbed their nests. Our findings generally support the high cognitive abilities hypothesis, but this ability can be acquired during a relatively short period in the life of an individual as a result of interactions between individual birds and humans.
KeywordsCognition Human recognition Pre-exposure Brown skua Antarctic bird
We specially thank to Dr. Joseph Covi for English help and Jan Esefeld for comments to improve the manuscript. We thank to Sung-Hoon Kim for helping fieldwork and being the “nest intruder”. This research was supported by the Long-Term Ecological Researches on King George Island to Predict Ecosystem Responses to Climate Change (PE14020) funded by Korea Polar Research Institute.
Compliance with ethical standards
Conflict of interest
The authors declare no conflict of interest.
The experiments comply with the current laws of Republic of Korea.
Discrimination experiment at a brown skua nest (BS03) on January 28, 2015 (ESM_1.mp4). (MP4 6071 kb)
Discrimination experiment at a brown skua nest (BS01) on January 26, 2015 (ESM_2.mp4). (MP4 20094 kb)