Individuality and stability in male songs of cao vit gibbons (Nomascus nasutus) with potential to monitor population dynamics.
Vocal individuality and stability has been used to conduct population surveys, monitor population dynamics, and detect dispersal patterns in avian studies. To our knowledge, it has never been used in these kinds of studies among primates. The cao vit gibbon is a critically endangered species with only one small population living in a karst forest along China-Vietnam border. Due to the difficult karst terrain, an international border, long life history, and similarity in male morphology, detailed monitoring of population dynamics and dispersal patterns are not possible using traditional observation methods. In this paper, we test individuality and stability in male songs of cao vit gibbons. We then discuss the possibility of using vocal individuality for population surveys and monitoring population dynamics and dispersal patterns. Significant individuality of vocalization was detected in all 9 males, and the correct rate of individual identification yielded by discriminant function analysis using a subset of variables was satisfactory (>90%). Vocal stability over 2-6 years was also documented in 4 males. Several characters of cao vit gibbons allowed long-term population monitoring using vocal recordings in both China and Vietnam: 1) regular loud calls, 2) strong individuality and stability in male songs, 3) stable territories, and 4) long male tenure. During the course of this research, we also observed one male replacement (confirmed by vocal analysis). This time- and labor-saving method might be the most effective way to detect dispersal patterns in this transboundary population.
Institute of Eastern-Himalaya Biodiversity Research, Dali University, Dali, Yunnan, P. R. China; College of Life Science, Southwest Forestry University, Kunming, Yunnan, P. R. China.
Jun-Juan
JJ
Feng
Key Laboratory of Forest Disaster Warning and Control in Yunnan Province, Southwest Forestry University, Kunming, Yunnan, P. R. China.
Liang-Wei
LW
Cui
Institute of Eastern-Himalaya Biodiversity Research, Dali University, Dali, Yunnan, P. R. China; College of Life Science, Southwest Forestry University, Kunming, Yunnan, P. R. China.
Chang-Yong
CY
Ma
Institute of Eastern-Himalaya Biodiversity Research, Dali University, Dali, Yunnan, P. R. China.
Han-Lan
HL
Fei
Institute of Eastern-Himalaya Biodiversity Research, Dali University, Dali, Yunnan, P. R. China.
Peng-Fei
PF
Fan
D000818:Animals; D002681:China; D016002:Discriminant Analysis; D056727:Endangered Species; D005843:Geography; D006922:Hylobates / Q000502:physiology*; D008297:Male; D011157:Population Dynamics; D013018:Sound Spectrography; D014744:Vietnam; D014828:Vocalization, Animal / Q000502:physiology*