The vocalization behavior of cat ba langur trachypithecus poliocephalus in cat ba national park

MINISTRY OF AGRICULTURE AND RURAL DEVELOPMENT VIETNAM NATIONAL UNIVERSITY OF FORESTRY STUDENT THESIS Title THE VOCALIZATION BEHAVIOR OF CAT BA LANGUR (TRACHYPITHECUS POLIOCEPHALUS) IN CAT BA NATIONAL PARK Major: Natural Resources Management Faculty: Forest Resources and Environmental Management Student: Do Bao Ngoc Student ID: 1453091115 Class: K59A Natural Resources Management Course: 2014 – 2018 Advanced Education Program Developed in collaboration with Colorado State University, USA Supervisor: Assoc Prof Vu Tien Thinh Hanoi, September 2018 ACKNOWLEDGEMENT First of all, I would like to sincerely thank you for my supervisor Assoc Prof Vu Tien Thinh and Mr Tran Van Dung have supported me in my studies, guides science in the research process, their patience, motivation, and extensive knowledge Thanks for two peoples who supported me during the research and writing of this thesis I sincerely thanks to Mr Nguyen Huy Cam (the forest ranger), Mr Mai Sy Luan (CBLCP), Cat Ba Langur Conservation Project Organization, FFI Organization, Cat Ba National Park I extremely thankful and grateful to them for sharing the knowledge, experience, and supported me about the boat and fuel for during this thesis Furthermore, I would like to thanks my family and my friends for supporting me in my research Without their support, I would not be able to complete the study During fieldwork due to time, the weather is not favorable, as well as access to the relatively difficult area Therefore, I will have the inevitable shortcoming in the research process I am looking forward to receiving the sympathy and comment from the teacher and friends to complete the thesis is better Thank you! Hanoi, September 2018 Do Bao Ngoc CONTENT ACKNOWLEDGEMENT PART I INTRODUCTION 1.1 Species overview 1.1.1 Taxonomy 1.1.2 Distribution 1.1.3 Morphological characteristics 1.1.4 The vocalization of trachypithecus 10 1.2 Conservation and threat of Cat Ba Langur 11 1.2.1 Conservation 11 1.2.2 Threat of Cat Ba Langur 13 PART II GOALS AND OBJECTIVE 14 2.1 Goal: 14 2.2 Objective: 14 2.3 Study area 14 PART III STUDY SITE 16 3.1 Natural conditions 16 3.1.1 Geographic location 16 3.1.2 Climate and hydrology 16 3.1.3 Vegetation 17 3.1.4 Fauna 19 3.2 Economy - Society 20 3.2.1 Population and employ 20 3.2.2 Livelihood 21 PART IV METHODOLOGY 24 4.1 Field surveys method 24 4.1.1 Determine the age/sex structure of Cat Ba langur 24 4.2 Data collection 27 4.3 Semi - structure interviews survey 29 4.4 Data analysis 29 PART V RESULTS AND DISCUSSION 30 5.1 Result 30 5.1.1 The status and structure of Cat Ba langur 30 5.1.2 Vocalization of Cat Ba langur 31 5.1.3 Vocalization behavior of Cat Ba Langur 35 5.2 Discussion: 37 5.2.1 Give some solution to improve the conservation and development of Cat Ba Langur 38 PART VI, CONCLUSION AND RECOMMENDATIONS 40 6.1 Conclusion: 40 6.2 Recommendations: 40 REFERENCES APPENDIX LIST OF FIGURES Figure 1.1: Map showing the distribution of Cat Ba langur populations in Cua Dong (southeast), the sanctuary (east), and Hang Cai (northwest) on Cat Ba Island, Vietnam Map, with permission, from Leonard (2014) Figure 1.2: Male Adult Photo by Nguyen Huy Cam 10 Figure 1.3: Female Adult Photo by Nguyen Huy Cam 10 Figure 1.4: Infant Photo by Nguyen Huy Cam 10 Figure 2.1: Cua Dong Photo by Neahga Leonard 14 Figure 2.2: Hang Cai - Gia Luan Commune Photo by Neahga Leonard 15 Figure 2.3: Sanctuary Photo by Neahga Leonard 15 Figure 4.1: Juveniles Photo by Nguyen Huy Cam 26 Figure 4.2 Subadults Photo by Nguyen Huy Cam 26 Figure 4.3: Newborn Photo by Nguyen Huy Cam 27 Figure 1.1: The sound spectrum of the Adult male 31 Figure 5.2: The sound spectrum of Juveniles 32 Figure 5.3: The sound spectrum of Infants 33 Figure 5.4: The behavior of Cat Ba langur 35 Figure 5.5: The vocalization behavior of Cat Ba langur by time 37 LIST OF TABLES Table 3.1: The population situation of the commune, town in Cat Ba island 21 Table 4.1: The characteristic of Cat Ba Langur 25 Table 4.2: The behavior of Cat Ba langurs 28 Table 4.3: Define the behavior of Cat Ba langurs 28 Table 5.1: Population size, age-sex classes for Cat Ba langurs as of July 2018 30 Table 5.2: The vocal frequency of adult males (n=6) 31 Table 5.3: The vocal frequency of juveniles (n=3) 33 Table 5.4: The vocal frequency of Infants (n=4) 34 Table 5.5: The number of vocal by individual 36 ABBREVIATION °C degrees Celsius CBLCP Cat Ba Langur Conservation Project CBNP Cat Ba National Park cm centimeter EPRC Endangered Primate Rescue Center FFI Fauna and Flora International Ha Hectare IUCN International Union for Conservation of Nature km Kilometers mm millimeter $ currency ($) for USA Hz Hertz ABSTRACT This study describes the vocalization behavior of Cat Ba Langur (Trachypithecus poliocephalus) in Cat Ba Island, Hai Phong City, Vietnam This research has never been described before The main objective is to describe and to identify the vocal of Cat Ba Langur Information derived from the recordings of the langur when I go to the field and then I used the Raven Pro software for analyzing the data For the result, I explored the maximum and minimum of the highest spectrum and the lowest spectrum of three individuals (Male adults, Juveniles and Infants), the time in the day them emitted the vocal and structure of the herd We detected groups with 59 individuals in the field and give some solution for conservation and development of Cat Ba Langur In natural, the langur always moving, so the operation of the voice recorder is not fixed and difficult for collected data Therefore, I should have a long time for study, need to collect data of Cat Ba langur on EPRC in Cuc Phuong National Park to compare the differences between the captive and the wildlife PART I INTRODUCTION Vietnam has a high diversity of primates; 25 species and subspecies of primates are known to occur there (Fooden 1996; Roos et al 2007; Van Ngoc Thinh et al 2010) However, a fast-developing economy combined with illegal wildlife trade, habitat degradation, and hunting has led to population declines in all species (Lippold and Vu Ngoc Thanh 1998) According to the result of the Asian Primate Assessment Conference in Singapore (2015), Primate in Vietnam is in particularly serious condition The number of species classified as "Critically Endangered" increased from species in 2008 to 11 species in 2015 One of these 11 species, arguably the most endangered in Vietnam is the Cat Ba langur (Trachypithecus poliocephalus), which occurs only on Cat Ba Island in Northern Vietnam Cat Ba langur (Trachypithecus poliocephalus) is a critically endangered langur Two subspecies are recognized: T p poliocephalus in Cat Ba Island, Vietnam, and T p leucocephalus in Guangxi, China The former (the nominate subspecies), often known as the golden-headed or Cat Ba langur, is among the rarest primates in the world, and possibly the rarest primate in Asia, with a population size estimated at less than 60 individuals Both subspecies are overall blackish, but the crown, cheeks, and neck are yellowish in T p poliocephalus, while they are white in T p leucocephalus, as suggested by its scientific name (ARKive Accessed, 2008) According to the Cat Ba Langur Conservation Project, the Cat Ba langur's skin is black and the pelage color is dark brown; head and shoulder are bright golden to yellowish-white The tail is very long (ca 85 cm) compared with the body size (ca 50 cm) Babies are colored golden-orange; the pelage starts to change its color from about the fourth month on Males and females look alike The Cat Ba Langur, which lives on Cat Ba Island in Vietnam, is one of the 25 most endangered primates Conservation efforts are helping to prevent this, however, and have greatly increased their population since 2003, when there were only 40 Until recently, the Cat Ba Langur was not considered a species but rather a subspecies of other Langurs that live in the Vietnam jungles (Mongabay Environmental News) Cat Ba Langurs are diurnal creatures and travel in groups of about four to eighteen animals They prefer the steep limestone cliffs that make up most of Cat Ba Island Most of the places that they are found are not accessible to humans by foot Cat Ba Langurs spend around 66% of their time resting and the rest moving, foraging, and socializing, with the distribution changing between summer and winter (Schneider et al, 2010) They eat less and rest more in the winter and the opposite in the summer The World Conservation Union (IUCN) lists the Cat Ba langur as one of the most critically endangered primate species in the world due to its small population size and restricted range Only about 60 langurs currently survive in the wild The Endangered Primate Rescue Centre at Cuc Phuong National Park is the only facility housing captive Cat Ba langurs (Cat Ba Conservation Project, 2006) In the past, poaching constituted the primary threat to langur survival and resulted in a population decline from an estimated 2,500-2,800 individuals in the 1960s, to a mere 53 individuals by 2000 As a result of this steep decline in numbers, the remaining langur population is now highly fragmented and low reproductive output threatens their future survival The population of the Cat Ba langur is scattered around the island in several isolated sub-populations Some of these include all-female groups with no access to males and are therefore non-reproducing social units Langurs were mainly poached for the preparation of traditional medicine, referred to as “monkey balm”, and only rarely for use as food, as their meat has a very unpleasant smell (Cat Ba Langur Conservation Project, 2004) In the world, there are many types of research about vocalization of Primate Example: "Calling patterns of Western purple-faced langurs (Mammalia: Primates: From the sound spectrum of infants, the sound spectrum of Infants is too large, and the sound of infants is "Chit Chit" It has two different types of shape sound but the sound is the same; the first sound has a shape like the parabolic curve and the second sound has the amplitude varies between the audio frequency and the negative length of the spectrum The vocal is almost the same and there is no big change The results of calculating the parameters of this type of vocal are shown in table 5.3 Table 5.4: The vocal frequency of Infants (n=4) Frequency (Hz) ID Time (s) Number of consecutive vocals Highest spectrum Lowest spectrum Max 21453 13340 1.46 Min 4380 4430 1.31 Average 12916.5 8885 1.38 12072 6300 0 Standard deviation The table 5.4 will provide the vocal frequency of infant with n=4 The results show the maximum of the highest spectrum is 21453 Hz, the minimum of the highest spectrum is 4380 Hz and the average of the highest spectrum is 12916.5 Hz In another hand, the maximum of the lowest spectrum is 13340 Hz, the minimum of the lowest spectrum is 4430 Hz and the average of the lowest spectrum is 8885 Hz So, the frequency of the highest spectrum and the lowest spectrum is too large The length of the vocal in the range from 1.31s to 1.46s 34 5.1.3 Vocalization behavior of Cat Ba Langur 5.1.3.1 The rate of vocalization behavior in the day The results of the monitoring of specific activities in Cat Ba Island area after the actual data collection has identified the operational time of the langur (figure 5.4) as follows: 5% 13% 29% Moving Resting 34% Foraging 18% Vocal Social behavior Figure 5.4: The behavior of Cat Ba langur This figure shows the behavior of Cat Ba langur in activities time of this species In this figure, we can see almost time in the day of Cat Ba langur is foraging with 34%, moving is 29%, resting is 18%, social behavior is 13% and the vocal is 5% So, we can easily see time in vocal in the day is very few, it accounts for 5% of the total daytime activity of this species 5.1.3.2 The appearance of vocalization behavior is related to age and sex 35 Table 5.5: The number of vocal by individual Individual The number of vocals (times) Averages (%) Newborn 0% Infant 32% Juveniles 11% Male Subadults 0% Female Subadults 0% Male Adults 11 58% Female Adults 0% The table shows the number of vocal by an individual when I collected data in the field In table 5.4, we can see the most vocal of Cat Ba langur is a male adult with 58% and after that is infants with 32% and juveniles is 11% In the natural, I did not get the vocal of female adults, newborn, male subadults and female subadults when I go to the field 5.1.3.3 The vocalization behavior of Cat Ba langur by time In the field trip, I collected three vocals from Cat Ba Langur I focused on three individuals were male adults, juveniles, and infants when I collecting data in the day So, the figure 5.5 will show the vocalization behavior of Cat Ba langur by the time of the day: 36 3,5 2,5 Male Adult Juveniles Infant 1,5 0,5 5h00-7h00 7h00-9h00 15h00-17h00 17h00-19h00 Figure 5.5: The vocalization behavior of Cat Ba langur by time Figure 5.5 shows the vocalization behavior of Cat Ba langur by the time of the day In this figure, we can see the male adults will vocal many times during the day such as 5h00 - 7h00 to calling the herd leaves the cave to go to the foraging; 7h00 - 9h00 it calling the herd moving to the valley or warning boundary and 17h00- 19h00 it calling the herd to go back the caves to sleep or warning boundary The infant is also vocal many times during the day in 7h00 - 9h00 and 17h00 - 19h00 because at this time, the infant usually shows the social behavior like jumping and playing with other individuals in the herd; and the juveniles vocal in 17h00-19h00 because it shows the social behavior in the herd 5.2 Discussion: The research results of the study showed in nature, Cat Ba Langur has three main types of vocalization including "Oc Oc", "Rit Rit" and "Chit Chit" The "Oc Oc" is often heard early in the morning and in the evening The male adults often emit a vocal of repetition two to three times It has the role of warning the boundary of the herd avoiding 37 the other herds invading the territory and it is the signal for the preparation to leaves the cave for a wake up to foraging in the morning or go to the cave for sleep in the evening The "Rit Rit" of the juveniles often emits when it was playing with another individual in the herd The "Chit Chit" of the infants often emits when it was playing with another individual in the herd or it needs your help when the herd moving to the difficult place or when the weather is heavy rain and cold However, in the morning when the herd was moving along the rocks and the trunk down to the foraging The male adults were emitted "Oc Oc" to warning the herd to stop all activities because it perceives danger The male adults were emitted much time to warn other herds not to encroach on its territory Moreover, when the two heads meet the male adults will emit a continuous sound until one of the two must leave or they will fight until one must die or go away in another place However, due to the research time and tools are limited, the ability to approach the primate is very difficult, so there may be many other forms of vocal of the adult male as well as the female adults, the subadults and newborn has not been recorded 5.2.1 Solutions to improve the conservation and development of Cat Ba Langur Conservation of the distribution of Cat Ba langurs in Cat Ba island, Cat Hai district, Hai Phong city It is necessary to strengthen the force of forest rangers and local people to jointly patrol and detect illegal hunting practices in this area In the study area, there are some issues such as firearms, hunting, trapping, wildlife trade, and forest product exploitation Therefore, it is necessary to implement the following programs: Strengthening patrolling activities of forest rangers in the core zone of the national park and the areas where langurs live Implement a voluntary weapon delivery program Execution of objects and penalties for violations 38 Strengthening propaganda measures to protect and educate the local people, especially the people living in the buffer zone around the live langur population Introduce many extracurricular activities to educate children about the biodiversity of the species in Cat Ba National Park Encourage further intensive research into the characteristics of Cat Ba species in the future for zoologists, students, and interns 39 PART VI CONCLUSION AND RECOMMENDATIONS 6.1 Conclusion: This thesis collected three types of vocalization behavior of Cat Ba Langur in three locations of Cat Ba islands like Cua Dong, Gia Luan Commune, and Sanctuary In this place, I collected three types of the vocal is "Oc Oc", "Rit Rit", "Chit Chit" of three ages is male adults, juveniles and infants For each type of vocal of each individual, there is information about the frequency, number of beeps and different vocal lengths In the vocals the frequency of the infant vocal is highest, then the frequency of the juveniles and the end of the adult male In behavioral activities, the vocal activity of the species is very low, accounting for 5% of all activities The vocalization behavior was emitted almost of male adults in the herd the percentage of vocalization behavior in male adults is highest with 58%, then infants with 32% and the last are juveniles with 11% The vocalization behavior of Cat Ba Langur by the time show us the time of three individual vocals by the time of the day For male adults, time vocal in the day from 5h00 to 7h00 and from 17h00 to 19h00 is the most And for the juveniles and infants, time vocal in the day from 17h00 to 19h00 is the most Give solutions to improve the conservation of Cat Ba Langur in the study site 6.2 Recommendations: The process of fieldwork in natural conditions in Cat Ba island, Cat Hai district, Hai Phong city due to the short time of research, the weather is rainy many days, the conditions of the study area are islands (including the marine ecosystems and forest ecosystems), close access to the langur is relatively difficult during the survey Therefore, the results obtained by the group are relative Due to the natural activities of the herd always moving, so the operation of the voice recorder is not fixed The sound of each 40 individual in the vocal is difficult to obtain due to the relatively high mountain terrain with low recording ability Therefore, we should have a long time for this research, need to collect data of Cat Ba Langur on EPRC in Cuc Phuong National Park It is necessary to collect more data on the sound of each individual Cat Ba langur to get more accurate results on individual voice characteristics of each 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Engineer thesis, Forestry University of Vietnam, Xuan Mai, Ha Tay, Vietnam APPENDIX Table 1: The vocal frequency of Juveniles Frequency (Hz) ID Maximum of highest spectrum Minimum of highest spectrum Maximum of lowest spectrum Minimum of lowest spectrum 14868 1114 13030 3787 13754 1392 10580 1671 15591 2339 7239 1225 Max/Min 15591 1114 13030 1225 Average 14737.7 1615.0 10283 2227.666667 Standard deviation 925.41 642.23 2906.90 1368.71 Table 2: The vocal frequency of Infant Frequency (Hz) ID Maximum of highest spectrum Minimum of highest spectrum Maximum of lowest spectrum Minimum of lowest spectrum 21403 4977 13340 4878 20656 4828 12643 5177 20507 5077 12842 4430 21453 4380 12294 5276 Max/Min 21453 4380 13340 4430 Average 21004.8 4815.5 12779.75 4940.25 Standard deviation 492.92 307.83 436.81 379.92 Table 3: The vocal frequency of male adult Frequency (Hz) ID Maximum of highest spectrum Minimum of highest spectrum Maximum of lowest spectrum Minimum of lowest spectrum 2534 2006 405 229 2904 2024 774 546 2492 2099 248 206 2450 1890 273 188 2730 2015 141 61 2432 1993 250 198 Max/Min 2904 1890 774 61 Average 2590.3 2004.5 348.5 238 187.35 67.33 224.86 162.11 Standard deviation Table 4: List of people interviewed ID Name Study area Job Vu Duc Tang Cua Dong Fishermen Tran Van Lenh Cua Dong Fishermen Pham Van Day Viet Hai/ Cai Minh Tu Fishermen Vu Van Chau Hang Cai/ Gia Luan Fishermen Vu Van Chu Hang Cai/ Gia Luan Fishermen Pham Ngoc Son Ranger Station of Van Ta/ Sanctuary Forest Ranger Nguyen Van Thiet Ranger Station of Gio Cung/ Sanctuary Forest Ranger Pham Van Man Ranger Station of Ang Ke/ Gia Luan Forest Ranger SOME PICTURE IN THE FIELDWORK ... Cat Ba National Park, 2006) 1.2.2 Threat of Cat Ba Langur Hunting of the Cat Ba langur used to be common The primary reason for hunting was to supply the traditional medicine industry Cat Ba langurs... species of crustaceans One of the rare species of Cat Ba is the large Dolphin, and Dolphin baby In the total number of marine species in the area of Cat Ba has found there are 21 rare species, including... repertoire of Cat Ba Langur - Identifying the calling pattern of Cat Ba Langur - Give solutions to improve the conservation of Cat Ba Langur 2.3 Study area - This research focus on locations in Cat Ba