Achievements and challenges of primate conservation in China

The dual impact of climate change and human activities has precipitated a sharp decline in primate biodiversity globally.China is home to the most diverse primate species in the Northern hemisphere,which face severe ecological threats due to the expansion of modern agriculture,extensive exploitation and consumption of natural resources,and excessive land development during its transition from an agricultural to a modern society.In response,China has implemented various ecological conservation measures,including habitat restoration and protection.These efforts have made substantial strides in biodiversity conservation,with certain regions witnessing an increase in primate populations.In the current study,we conducted a systematic review of historical documents and field research data related to Chinese primates,evaluating the endangered status of primate species in China.Despite improvements in the habitats of most primate species and some population growth,many species still face severe threats,including declining and small populations.Species such as the Myanmar snub-nosed monkey(Rhinopithecus strykeri),eastern black crested gibbon(Nomascus nasutus),and Hainan gibbon(N.hainanus)remain particularly vulnerable due to their limited distribution ranges and extremely small populations.Insufficient scientific data,fragmented information,and not enough studies in conservation biology further compound the challenges.Moreover,there is a notable lack of detailed population monitoring data for species such as the Bengal slow loris(Nycticebus bengalensis),pygmy slow loris(N.pygmaeus),Indochinese gray langur(Trachypithecus crepusculus),Shortridge’s langur(T.shortridgei),and capped langur(T.pileatus),which hinders the development of practical and targeted conservation management strategies.Therefore,for national biodiversity conservation,there is an urgent need for specialized primate surveys,enhancing habitat protection and restoration,and increasing focus on cross-border conservation strategies and regional cooperation.There is also a need to establish a comprehensive and systematic research database platform,conduct continuous and in-depth research in primate biology,and actively engage in the scientific assessment of ecotourism.Additionally,strengthening public awareness and education on wildlife conservation remains essential.Such integrated and systematic efforts will provide scientific support for the current and future conservation and management of primate species in China.

Positional behavior and canopy use of black snub-nosed monkeys Rhinopithecus strykeri in the Gaoligong Mountains,Yunnan,China

Studies on positional behavior and canopy use are essential for understanding how arboreal animals adapt their morphological characteristics and behaviors to the challenges of their environment.This study explores canopy and substrate use along with positional behavior in adult black snub-nosed monkeys Rhinopithecus strykeri,an endemic,critically endangered primate species in Gaoligong Mountains,southwest China.Using continuous focal animal sampling,we collected data over a 52-month period and found that R.strykeri is highly arboreal primarily using the high layers of the forest canopy(15–30 m),along with the terminal zone of tree crowns(52.9%),medium substrates(41.5%),and oblique substrates(56.8%).We also found sex differences in canopy and substrate use.Females use the terminal zones(56.7%versus 40.4%),small/medium(77.7%versus 60.1%),and oblique(59.9%versus 46.5%)substrates significantly more than males.On the other hand,males spend more time on large/very large(39.9%versus 22.3%)and horizontal(49.7%versus 35.2%)substrates.Whereas both sexes mainly sit(84.7%),and stand quadrupedally(9.1%),males stand quadrupedally(11.5%versus 8.3%),and bipedally(2.9%versus 0.8%)more often than females.Clamber,quadrupedalism,and leap/drop are the main locomotor modes for both sexes.Rhinopithecus strykeri populations never enter canopies of degenerated secondary forest and mainly use terminal branches in the middle and upper layers of canopies in intact mid-montane moist evergreen broadleaf forest and hemlock coniferous broadleaf mixed forests across their habitat.

Infanticide in golden snub-nosed monkeys with multilevel society

Infanticide,killing unweaned offspring in conspecifics,occurs widely among mammals,such as rodents,ungulates,and carnivores,especially in primates(Lukas and Huchard 2014).Such scenarios are often triggered by intruders that have replaced the former dominant males in nonhuman primates(Borries 1997).It has widely been viewed that infanticide is one of the solutions of sexually driven evolutionary selection:males kill infants to end lactational amenorrhea of the victim's mothers,forcing them to return to estrus and providing infanticidal males with the opportunities to sire their new offspring(Hrdy 1979).There is a broad spectrum regarding the patterns and mechanisms causing such events,referring to alternative breeding behaviors and mating systems-monogamy,polyandry,polygyny,and promiscuity(Qi et al.2020).

Facial expression recognition in golden snub-nosed monkeys

For socialized animals,such as prinlates,emotions arc the expression of internal states,which may be recognized by others to adjust an in dividual's potential actions(Girard and Bellone 2020).Facial expressions are therefore important signals in communication(e.g.,happy or in pain)and can help individuals understand potential meanings between each other(Dolensek et al.2020).Facial expressions can be expressed and processed freely and are useful in social interactions and bonding(Waller et al.2016).