INTRODUCTION
There are approximately 4,000 snake species across 520 genera and 20 families worldwide, excluding Antarctica and smaller land masses (Uetz et al 2022) Despite their negative reputation, snakes play a crucial role in maintaining ecological balance and controlling pest populations, providing essential services to humans Celebrated in various cultures, many snake species face threats due to human conflict, with 11.7% classified as threatened (Bohm et al 2013) Major threats include habitat loss, road mortality, intentional killings, and poaching (Santos et al 2008; Datta et al 2018).
Vietnam hosts over 200 snake species, primarily found in its tropical forest habitats, with their distribution spanning from the north to the south of the country However, these snakes face significant threats, including habitat loss, hunting, poaching, and the production of snake wine.
Vietnam and Laos share a border exceeding 2,000 km, with limestone mountain ecosystems primarily found in provinces such as Dien Bien, Son La, Thanh Hoa, Nghe An, Ha Tinh, Quang Binh, and Thua Thien-Hue These ecosystems, ranging from sea level to over 2,000 m in altitude, feature diverse structures like terrestrial islands, mountain ranges, and caves, which are biologically rich and highly endemic The unique micro-habitats created by natural islands are crucial for species evolution However, this sensitive mountain ecosystem is vulnerable to human impact, making restoration challenging In Vietnam, limestone ranges have faced unsustainable exploitation for infrastructure development and tourism.
Son La Province is located in the Northwest region of Vietnam bordering with Laos (Houaphanh province) In 2009, Nguyen et al recorded
42 snake species for Son La province In the following years Pham et al
In 2013 and 2014, a total of 11 additional species were documented Notably, in 2015, Vietnam saw the first recordings of two species: Trimerodytes yunnanensis by Le et al and Parafimbrios lao by Teynié et al., both identified at Sop Cop and Copia Nature Reserve.
In 2019, a new species, Achalinus timi, was described in the Copia Nature Reserve by Ziegler et al Additionally, Luu et al reported a new record of Ptyas nigromarginata in Son La The following year, Pham et al identified five more new species of snakes, while in 2021, Dinh et al documented a new record of Naja kaouthia for the province Currently, there is one new species under consideration.
Achalinus vanhoensis have been published in Van Ho district by Ha et al
(2022), combination with the previous data to bringing the total number of snakes to the whole Son La province to 64 species
Tan Xuan, Chieng Tuong and Chieng Khua are three communes of Son
The province bordering Laos has limited specific investigations and studies on the fauna of its communes However, in Tan Xuan commune, there have been two prior research efforts conducted by Nguyen et al (2009) and Nguyen et al.
As of 2010, a total of 32 species have been documented in Xuan Nha commune and Xuan Nha Nature Reserve However, there is a significant lack of information regarding vertebrates in these areas, particularly concerning snakes, which are often overlooked in terms of species diversity, conservation status, and habitat.
This research focuses on the "Taxonomy, Ecology, and Conservation of snakes (Serpentes) in the border area between Laos and Son La Province." The primary aim is to investigate the diversity, ecological roles, and conservation strategies for snake species in this region.
LITERATURE REVIEW
Snake fauna diversity in Southeast Asia
Since 2010, the number of snake species in several Southeast Asian countries has seen a slight increase Timor Leste has added one species, raising its total from 14 to 15 Meanwhile, Myanmar, Malaysia, Laos, the Philippines, and Cambodia have experienced increases of 12, 10, and 8 species, respectively.
6 and 5 species, respectively with total being 223 (Malaysia), 191 (Myanmar),
147 (Philippines), 113 (Laos) and 102 (Cambodia) Thailand and Indonesia have increased 20 species a total of 238 and 371 respectively Vietnam have the highest increases of snakes in Southeast Asia with 37 species and total
262 In two other countries, Singapore and Brunei there were no new species descriptions for snakes (Uetz et al 2022)
Figure 2.1 Diversity of snakes in Southeast Asia countries during 2010 –
Snake fauna research in Vietnam
As of 2022, Vietnam is home to 262 snake species, showcasing a diverse distribution across plains, midlands, mountainous regions, forests, and waterways The discovery of new species has surged, with 32 new snake species identified over the past twelve years, highlighting the rich biodiversity of Vietnam's herpetofauna.
Figure 2.2 Number of snake species descriptions increases over 12 years in Vietnam (Source: Uetz et al 2022)
The book Herpetofauna of Vietnam was published by Nguyen et al
(2009) noted that Vietnam has 190 species of snakes Also in 2009, there are
Five new snake species have been discovered in Vietnam, including Calamaria abramovi and Calamaria sangi in Kon Tum Province, Calamaria gialaiensis in Gia Lai Province, Colubroelaps nguyenvansangi in Lam Dong Province, and Protobothrops trungkhanhensis in Cao Bang Province, all identified in 2009 According to data from Uetz et al (2022), the total number of snake species in Vietnam reached 228 in 2009 when combining these new findings with previous studies.
2010, there was only 1 new species have been found in Thua Thien – Hue,
Orlov et al (2010) identified Calamaria concolor, bringing the total number of snake species in Vietnam to 229 Additionally, Nguyen et al conducted research on species diversity in the Xuan Nha Nature Reserve located in Son La Province.
As of 2010, a total of 28 snake species have been documented in this Nature Reserve In 2011, two new species were discovered in Vietnam: Opisthotropis cucae in Kon Tum Province, reported by David et al., and Emydocephalus szczerbaki in Ba Ria - Vung Tau, identified by Dotsenko.
In a notable study, Geissler et al documented 51 snake species in Cat Tien National Park, located in Dong Nai and Lam Dong Provinces Similarly, Nguyen et al identified 20 snake species in the Cat Ba Archipelago Biosphere Reserve in Hai Phong during the same year.
1 new species have been found in Cao Bang Province Oligodon nagao by
David et al (2012) In 2013, there were 2 new species have been found in Vietnam, Azemiops kharini in Tam Dao Province by Orlov et al (2013) and
In 2013, Vassilieva et al documented Oligodon cattienensis in Lam Dong Province, while Luu et al reported 58 snake species in Phong Nha – Ke Bang National Park Additionally, Hoang et al compiled a checklist of herpetofauna for Kon Ka Kinh National Park, which included 21 snake species, as noted by Nguyen & Hoang.
In recent years, several studies have contributed to the understanding of snake diversity in Vietnam's nature reserves and national parks A checklist by (2013) identified 28 snake species in the Binh Chau – Phuoc Buu Nature Reserve, while Dang & Nguyen (2013) documented 7 snake species in the Phia Oac – Phia Den National Park Additionally, Le et al (2014) reported 46 snake species in Dien Bien, Pham et al identified 51 species in Son La Province, and Ziegler et al published findings on 30 snake species in Ha Giang Province.
10 snakes in Xuan Son National Park, Phu Tho Province In 2015, there were
2 new species Oligodon arenarius in Ba Ria-Vung Tau by Vassilieva, (2015) and Cylindrophis jodiae in Central Vietnam by Amarasinghe et al (2015),
In recent years, significant discoveries in snake species have been reported in Vietnam Pham et al (2015) documented 25 snake species in Son La Province The following year, Nguyen et al (2016) identified a new species, Oligodon condaoensis, on Hon Ba Island, while also reporting 25 snake species in Phu Yen District and 38 species in Xuan Lien Nature Reserve, Thanh Hoa Province In 2017, another new species, Oligodon culaochamensis, was discovered in Quang Nam Province by Nguyen et al Additionally, Tran Thi Hong Ngoc reported 18 snake species in the Trang An World Heritage area, and Nguyen et al documented 21 species in the Muong Bang area of Phu Yen, with Pham et al publishing 20 species from Son La and Dien Bien Provinces The following year, Ziegler et al (2018) identified two new species, Opisthotropis voquyi in Bac Giang and Parafimbrios vietnamensis in Lai Chau, further enriching Vietnam's herpetological diversity.
Recent studies have expanded our knowledge of snake species in Vietnam, with Le et al documenting 25 species in Yen Bai Province and Nguyen et al identifying 43 species in Hoa Binh Province In 2019, Hoang Van Ngoc and Pham Van Anh reported 51 snake species in Thai Nguyen Province, while Pham Van Anh and Nguyen Quang Truong noted 26 species in Lai Chau Province Additionally, Nguyen et al published findings on 26 snake species in Binh Dinh Province Notably, nine new snake species have been described, including Opisthotrips haihaensis from Quang Ninh Province, Calamaria dominici from Dak Nong, and Achalinus juliani from Cao Bang.
Province, Achalinus timi in Son La Province, Achalinus emilyae in Quang
Ninh by Ziegler et al (2019), Lycodon namdongensis in Thanh Hoa Province by Luu et al (2019), Calamaria strigiventris in Lam Dong Province and
Recent studies have identified new snake species in Vietnam, including Liopeltis pallidonuchalis in Gia Lai Province (Poyarkov et al., 2019) and Lycodon pictus in Cao Bang Province (Janssen et al., 2019) Additionally, Oligodon rostralis has also been published as a new species.
In 2020, significant contributions to herpetology were made with the identification of various snake species, including Achalinus tranganensis in Trang An, Ninh Binh by Luu et al., and Achalinus zugorum in Ha Giang Province by Miller et al Additionally, Luu et al reported a total of 50 species in BV-NP, comprising 36 snake species, while Pham et al documented 61 snake species in Son La Province The following year, 2021, saw the publication of three new species, including Ahaetulla rufusoculara in Soc Trang Province by Lam et al and Hebius igneus in Tuyen.
Quang province by David et al., Pareas temporalis in Lam Dong province by
Le et al Currently in 2022, there are 5 new species have been published including: Lycodon anakradaya and Lycodon truongi in Khanh Hoa by
Nguyen et al., Pareas abros in Quang Nam, Thua-Thien Hue and Pareas kuznetsovorum in Phu Yen by Poyarkov et al., Achalinus vanhoensis in Son
La by Ha et al
Snake fauna research in Laos
Over the past decade, there has been a significant increase in the understanding of snake species diversity in Laos Initially, Stuart (1999) provided the first checklist, identifying 57 snake species in the region Subsequently, Teynié et al (2004) released an updated checklist of reptiles from southern Laos, further contributing to the knowledge of this diverse fauna.
Over the years, significant progress has been made in documenting snake species in Laos Initially, 27 species were identified, but by 2008, Stuart and Heatwole recorded an additional 13 colubrid and viperid species A comprehensive checklist published by Nguyen et al in 2009 noted a total of 79 snake species in Laos, based on findings from Vietnam In 2010, Das expanded the knowledge further with a field guide that listed 100 snake species, while Teynié and David confirmed 104 species in Laos the same year By 2012, two new species, including Lycodon davidi, were discovered, highlighting the ongoing exploration of Laos' rich herpetological diversity.
In recent years, several new snake species have been identified in Southeast Asia Notably, Vogel et al (2012) and David et al (2012) described Oligodon nagao In 2014, Teynié et al introduced a new species from the Natricidae family, named Opisthotropis durandi, discovered in Louangphabang, Laos Additionally, in 2015, a new species called Parafimbrios lao from the Xenodermatidae family was found.
Louangphabang, Laos, is highlighted in the field guide by Vassilieva et al (2016), which details the amphibians and reptiles of the lowland monsoon forests of Southern Vietnam This guide identifies a total of 43 snake species distributed in Laos, based on the species found in Vietnam Two years later, a new species from the genus was discovered.
Lycodon banksi was discovered in Khammounane, Laos, by Luu et al in 2018 Two years later, Ding et al identified a new species, Pareas geminatus, in the Houaphan and Xaisomboun Provinces of Laos.
Next year, a new species Calamaria nebulosa have been found in Phongsaly Province, Laos by Lee, 2021 At present, the number of snake species from Laos is 113 species (Uetz et al 2022)
- Snake fauna research in north-eastern region of Laos
Houaphan, a northeastern province of Laos bordering Vietnam's Son La province, has limited research on herpetofauna, with only six publications focusing on its snake fauna Notably, in 1998, Bryan Stuart documented six snake species in Nam Et-Phou Louey, including Python bivittatus, Malayopython reticulatus, Elaphe taeniura, Lycodon cf capucinus, Oreocryptophis porphyraceus, and Bungarus candidus.
National Biodiversity Conservation Area, Houaphan province In 2008, Stuart and Heatwole recorded 1 individual of Trimerodytes percarinatus from Phou
Louey National Biodiversity Conservation Area, Houaphanh province In
2015, Teynié et al found a new species Parafimbrios lao from family
In Houaphanh province, the Xenodermatidae family was represented by a second specimen Five years later, Nguyen et al (2020) reported the discovery of five additional species in the region, which include Dendrelaphis cf cyanochloris, Hebius chapaensis, Pareas hamptoni, Pareas macularius, and Pareas margaritophorus.
In 2020, Ding et al identified a new species, Pareas geminatus, in Houaphan The following year, Zuklin et al documented eight additional species in Nam Et Phou Louey National Park, including Ahaetulla prasina, Boiga multomaculata, Ptyas korros, Ptyas multicincta, and Fowlea flavipunctatus.
Ophiophagus hannah, Trimeresurus albolabris, Trimeresurus vogeli
Currently in 2022, a new country record of species Trimerodytes yapingi in this area have been published by Dinh et al., the number of snakes in
Houaphan province is 23 species (temporary).
Snake diversity in border areas with Laos of Son La Province
In 2009, Nguyen et al have been recorded 25 species in Xuan Nha Commune
In 2010, Nguyen et al presented a checklist of amphibians and reptiles, which included a total of 28 snake species However, there has been a lack of recent research or articles concerning herpetofauna in the regions of Chieng Tuong, Chieng Khua, and Tan Xuan Most studies and documentation in Son La have concentrated on the Xuan Nha Nature Reserve and Sop Cop Nature Reserve.
Reserve, Copia Nature Reserve, Thuan Chau District, Song Ma District, Phu
Yen District (Pham et al 2013; Pham et al 2014; Pham et al 2020).
GOAL, OBJECTIVES, AND RESEARCH QUESTIONS11
Goal
This article aims to present essential insights into the diversity of snake species in three study sites located in Son La province, which borders Laos Additionally, it offers recommendations for the conservation of snake fauna in these areas.
Specific Objectives
To investigate the snake species composition in the study sites
To identify the distribution of snake species across habitat types and elevations in the study sites
To assess threats to snake fauna in the study sites
To recommend solutions for conservation and management of snake fauna in the study sites.
Research Questions
- How many snakes are there?
- Which habitat types and elevation does they usually live?
- What factor can be their threats?
- Which solution can be used in order to protect and manage their populations?
STUDY AREA
Location
According to the resolution 155 of Son La Province People's Council
Tan Xuan Commune, as reported by the People's Committee in 2013, covers a total area of 15,819.3 hectares, with 985.1 hectares designated for agricultural use The commune is comprised of nine villages, including Buot and Dong Ta Lao.
Tay Ta Lao, Nga, Bun, Lay, Moc Moc, A Lang, Sa Lai villages
Coordinates: Latitude: 20⁰ 37’56.30” North/ Longitude:104⁰ 44’25.54” East The North border Xuan Nha commune, Chieng Xuan commune, Moc Chau district, Son La Province
The South border Tam Chung commune, Trung Ly commune, Muong Lat district, Thanh Hoa Province
Cun Pheo commune in Mai Chau district, Hoa Binh Province, shares its eastern border with Trung Son commune in Quan Hoa district, Thanh Hoa Province, while its western border is adjacent to Sop Bau district in Laos and Chieng Son commune in Moc Chau district Additionally, Chieng Khua commune is also mentioned in this context.
According to the People's Committee of Chieng Khua Commune (2020): Chieng Khua is a commune in Moc Chau district, Son La province,
Vietnam Chieng Khua commune has an area of 84.36 km²
Coordinates: Latitude: 20⁰ 50’33.46” North/ Longitude:104⁰ 27’38.46” East Chieng Khua commune is located adjacent to:
- The Northeast borders Chieng Hac commune
- The East borders Muong Sang commune
- The West borders Chieng Tuong commune, Yen Chau district
- The South borders the Lao People’s Democratic Republic
- The Southeast borders on Long Sap commune c Chieng Tuong Commune
Chieng Tuong commune, as reported by the People’s Committee in 2021, is a highland area situated along the Long Phieng Chieng Khua inter-commune road, 52 km from the district center and 21 km from the Laos border Covering a total natural area of 6,995.5 hectares, the commune is home to 9 families and consists of 9 villages, including 4 that are located along the border.
Coordinates: Latitude: 20⁰ 50’33.46” North/ Longitude:104⁰ 27’38.46” East
- The Eastern borders Chieng Khua commune
- The Northern borders Long Phieng commune
- The West borders Mong Nam area, Xieng Kho district, Houaphan province, Laos
- The Southern border is adjacent to Mong Nam commune (Laos).
Climate
Tan Xuan commune, situated in Zone II of Son La province, is characterized by a climate influenced by the northwest mountainous region.
- The average temperature in the year is 19.5 o C
- The average annual humidity is 85%
- The total average rainfall is 125mm/month
- Sunny: The average total number of sunshine hours per year is 1,850 hours/year
Tan Xuan experiences significant climatic influences from two primary wind directions: the northeast monsoon during the cold season and the southeast wind in the hot season The cold months see higher evaporation rates than rainfall, leading to drought conditions Temperatures can drop to between 30 and 70 degrees Fahrenheit for extended periods, severely impacting agricultural productivity and livestock in the region.
According to the monitoring data of the hydro-meteorological station in the Moc Chau area, the measured climate and weather factors are as follows:
- The average temperature in the year is 17.5°C
- The average annual humidity is 80%
- Total average rainfall is 130 mm/month
- Total average sunshine hours per year is 1,850 hours/year c Chieng Tuong Commune
Chieng Tuong experiences two distinct seasons: the rainy season, which often leads to floods that damage crops and agricultural products, and the dry season, lasting from December to August, where temperatures can soar to 34-35 degrees Celsius As a highland commune with limited rivers and streams, Chieng Tuong faces significant water scarcity during the long dry season, causing many villages to lack access to daily water for up to a week, forcing residents to wake up early to secure water for their families.
Forestry resources
As of the 2010 inventory, the commune boasts a substantial forest area of 10,178.68 hectares, representing 64% coverage This includes 452.61 hectares designated as protection forest, 2,246.27 hectares as production forest, and 7,479.80 hectares classified as special-use forest The commune's forests are home to numerous rare and valuable species of flora and fauna Moving forward, it is crucial to prioritize the protection of the existing forest areas, particularly the special-use forest.
The natural area of the commune: 15,855.00 ha Which includes:
- Agricultural land 11,100.92 ha, accounting for 69.45% of the total natural area of the commune
+ Land for upland rice cultivation: 340.00 ha
+ Land for growing annual crops: 392.24 ha
+ Land for perennial crops: 34.50 ha
+ Protection of forest land: 452.61 ha
+ Special-use forest land: 7,479.80 ha
- Non-agricultural land: 162.96 ha, accounting for 1.03% of the total natural area
+ Residential land (residential areas): 23.96 ha
+ Land for headquarters, non-business agencies: 0.97 ha
+ Land for public purposes: 45.13 ha
+ Land for cemeteries and graveyards: 3.00 ha
+ Land for rivers, streams and water surface for special use: 62.44 ha
- Unused land 4,705.08 ha, accounting for 29.68% of the total natural area b Chieng Khua Commune
Enhancing the management and protection of existing forests is crucial This involves promoting awareness, conducting inspections, and enforcing regulations to prevent and address violations In 2019, contracts were established with village management boards and local households to ensure the care and protection of these vital forest resources.
In 2019, inspections revealed 5 violations, a decrease of 31 cases from 2018 The primary issue involved illegal forest clearing for cultivation, affecting an area of 5,674 m² The People’s Committee compiled a dossier and decided to suspend 2 cases while transferring 3 cases to the district for further handling.
The terrain of the commune is complicatedly divided, there are 3 types of terrain as follows:
- High mountainous terrain, concentrated in the areas adjacent to Chieng Tuong commune, Yen Chau district and the area bordering Vietnam – Laos, the average altitude is about 1000 – 1200 m a.s.l
- The terrain is a low hill and alluvial, with an average altitude of 700 –
900 m above sea level, this terrain is distributed in Xa Lu, Ong Ly … c Chieng Tuong Commune
Chieng Tuong commune spans a total natural area of 6,993.00 hectares, with 4,203.53 hectares designated for agriculture, 3,362.75 hectares for forestry and industrial crops, and 108.77 hectares for specialized use The terrain is predominantly hilly and rocky, making it suitable for both short- and long-term industrial crop cultivation Despite its mountainous landscape, the area is capable of producing valuable timber, medicinal herbs, and stones for various production and construction materials.
Figure 4.2 Topography map of these three communes that border with Laos
METHODS
Field surveys and data collection
Before conducting a field survey, it is essential to study and identify snake species by gathering information from documents and the internet regarding the investigation and composition of snakes in the area Additionally, preparation includes creating a map of the study area and assembling materials for snake identification Special tools and chemicals necessary for the survey activities include surgical instruments, specimen preservation bottles, cameras, headlamps, labels, GPS devices, ethanol, ethyl acetate, cloth bags, snake tongs, and snake hooks.
- Site selection: Survey sites have been selected at elevation ranges from 400 to 1000 m above sea level (a.s.l.)
- Survey time: from May 17 th 2022 to May 25 th 2022; June 10 th
2022 to June 21 st 2022 and June 25 th 2022 to July 2 nd 2022
Figure 5.1 Map of transects survey in Tan Xuan commune
Figure 5.2 Map of survey transects in Chieng Khua commune
Figure 5.3 Map of transects survey in Chieng Tuong commune
Table 5.1 List of survey transects, survey time and participants
No Location Transect number Transect name Survey time
Transect 1 Lay village – Bun village 2 3
Transect 2 Bamboo forest (Bun village) 3 4
Transect 3 Bun stream (Bun village) 4 4
Transect 4 Rice field (Bun village) 2 4
Transect 9 In stream (Bun village) 3 4
Transect 5 Rice field (Ong Ly village) 3 4
Transect 6 Ong Ly stream (Ong Ly village) 4 4
Transect 11 Huoi Tu forest (Ong Ly village) 1 4 Transect 12 Huoi Luong stream (Ong Ly village) 1 4
Transect 7 Pa Khom Cave (Pa Khom village) 2 4
Transect 8 Pa Khom Stream (Pa Khom village) 2 4 c Data collection
- Main collection time from 19:00 pm to 23:00 pm
Specimens were collected by hand for non-venomous species or using snake tongs and hooks for venomous ones Each specimen was photographed and documented in a survey note, with common species released back into their environment Unidentified individuals or potential new species, consisting of 1-2 specimens each, were collected for taxonomic analysis and identification at the VNUF laboratory.
Funnel traps are an effective solution for enhancing species detection in line transect surveys, particularly for elusive and camouflaged species like snakes Traditional methods often struggle with identifying species in the field due to morphological similarities, necessitating specimen collection for accurate classification Increasing survey frequency and duration can be financially and temporally inefficient, potentially disturbing local wildlife By implementing funnel traps, researchers can improve species recording while minimizing impact on the surrounding environment and optimizing resource use (Scott et al 1994; Fisher & Rochester, 2012).
Figure 5.4 Location of funnel trap in the study area
- Steps for design and set up funnel trap
Trap material: flexible metal mesh, with a mesh size of 1x1 mm; 1 mm diameter ductile steel wire
Cut 2 sheets of material 100 cm x 70 cm and a circle with a diameter of
100 cm, then cut the circle in half (Figure 5.5)
Figure 5.5 Material for trap making (Design by Russell Gray)
To create a compartment from a 100 cm rectangular mesh, first fold down one side by approximately 3 cm Next, fold the remaining 3 cm upwards and secure it with pins to form creases on both sides Finally, press the pinned side down against the fold of the opposite side and fold the other two sides to complete the rectangular shape.
To create the desired shape, first, fold the staples back and pin them flat on the drawer Next, fold the half circle along the straight sides until a hole measuring approximately 6 cm to 10 cm wide is formed, and pin it to the top of the fold Finally, join the two overlapping body and funnel pieces and pin them in place.
Figure 5.6 Funnel and trap body (Design by Russell Gray)
Insert the funnel into the compartment, fold the top of the funnel over the edges of the compartment and pin it in place
Insert compartment 2 (C2) into the funnel of compartment 1 (C1) about
To connect the two compartments, fold the body of C1 into C2 at a length of 10 cm and secure it with a stapler Additionally, a 1 mm diameter flexible steel wire can be threaded between the folds of C1 and C2 for added stability (Figure 5.7).
Figure 5.7 Connecting the two heads of the funnel and the trap compartment (Design by Russell Gray)
To create a triangular fold on both sides of the two compartments, push the edges on the back together, secure them with pins, and then fasten the tail of the trap using flexible iron wire (see Figure 5.8).
Figure 5.8 Fixing and completing the funnel trap (Design by Russell Gray)
Set up the funnel trap in the field survey
Step 1: Select mixed forest habitat with many wooden tree species, slope less than 15-degree, high humidity and few people walking around At least 20 meters from trails
Step 2: Choose the central tree
Look around, choose a tree with a diameter of about 15-20 cm Ensure enough firmness, do not tilt, do not fall by the impact of human or wind
Step 3: shape determination before set up trap
To establish a stable structure, stretch a nylon rope from a central tree to three surrounding trees, creating three grid lines that form approximately 120-degree angles Each line should measure a total length of 10 meters, effectively securing the branches.
To create a sturdy structure, dig a trench that is 20 cm deep and 10 cm wide, ensuring the soil is evenly spread to both sides Simultaneously, take a bamboo stick, split it in half, and drive each half deep into the ground to a depth of 20-25 cm, positioning the pillars 1 meter apart.
To install the net along the trench, first dig the trench to the desired depth, then adjust the net's depth to match that of the trench Secure the net using a small malleable iron wire, measuring 0.5 mm in diameter, to attach it to a bamboo pole and nylon rope.
After making the grid, the 3 grid lines connect together to form a Y shape
To effectively capture targets, position two funnel traps at each end of the net along the grid lines, ensuring that the trap mouths face each other Once the traps are set, secure them to the net using flexible iron wire for stability.
Figure 5.9 Diagram of funnel trap system (Design by Russell Gray)
- Anaesthetization: Within 24 hours after collecting, the selected animals anaesthetized and euthanized in a closed vessel with a piece of cotton wool containing ethyl acetate (Simmons, 2002)
Every specimen collected is labeled with a tag that includes essential information such as the locality (e.g., TX, CK, CT), field number, and date of collection Subsequently, each specimen is assigned a museum number (VNUF) for identification purposes.
- Fixing in 80% ethanol for 4-6 hours, and then transfer to 70% ethanol for permanent storage Tissue samples preserved separately in 95% ethanol for further study.
- Specimen management: Collected specimens deposited in the collection of Vietnam National University of Forestry (VNUF), Hanoi, Vietnam
- The following abiotic data was recorded for every single collected individual
Geographic coordinates and elevation were tracked using a Garmin 62st or GPSmap 78s, while air temperature and humidity were measured with an Atech KW307-CSJ digital thermos-hygro-barometer, which has an accuracy of 0.1% for temperature and 1% for relative humidity Additionally, data on habitat characteristics, ground distance, and the presence of nearby streams or trails were recorded.
All the data in the survey time recorded in a survey note and survey sheet (Table 5.2 & 5.3)
Transect name………; Day… month… year 2022
Species name………; Name of GPS………
Sex Time Coordinate Habitat Date Temperature Humidity Note d Data analysis
The morphological examination of specimens collected from Tan Xuan, Chieng Khua, and Chieng Tuong was conducted at the VNUF laboratory Morphometric measurements were taken using an Etopoo digital caliper with a precision of 0.1 mm, while scale counts were performed with a Leica S6E electron microscope The terminology for morphometric characters adhered to the standards set by Manthey & Grossmann (1997).
Table 5.4 Abbreviations of main morphological characteristics
1 SVL Snout-vent length (from tip of snout to anterior margin of clocal)
2 TaL Tail length (from posterior margin of clocal to tip of tail)
3 TL Total length (from tip of snout to tip of tail)
4 TaL/TL Ratio of tail length divide total length
5 HL Head length (from the tip of snout to the back of mandible)
6 HW Head width (the largest pattern of the head)
Table 5.5 Abbreviations of scales in snake group
Figure 5.10 Scale in head pattern of snake (Manthey & Grossmann, 1997)
Figure 5.11 Body scale count (Manthey & Grossmann, 1997) a) Oblique count, b) V-shape count, c) Alternate count
Figure 5.12: Ventral, subcudal and cloacal scale
The morphological characteristics of specimens from the study sites were compared with existing literature, including species descriptions, identification keys, and reviews from Vietnam and neighboring countries Key references include Smith (1943), Ziegler et al (2007), Nguyen Van Sang (2007), David et al (2011), Ziegler et al (2017), and Luu et al (2019).
Comparisons of the species similarity composition between border
The correlation of species composition between regions is analyzed using PAST Statistic software (Hammer et al 2001) Data is represented in a symmetric format, where 1 indicates presence and 0 indicates absence The Sorensen-Dice index is computed with the formula \$d_{jk} = \frac{2M}{2M + N}\$, where \$M\$ represents the number of species found in both regions, and \$N\$ denotes the total number of species unique to one region.
Evaluating conservation status of snake species
The conservation status of snake species is assessed using various criteria, including the Vietnam Red Data Book (RBVN, 2007), the IUCN Red List of Threatened Species (IUCN, 2022), and Governmental Decree No 84/2021/ND-CP.
Table 5.9 List of threatened species
Conservation status IUCN (2022) Decree 84 RVBN (2007)
Conservation issues
Several factors significantly affect snake populations, including hunting, poaching, habitat loss and degradation, overexploitation, and livestock breeding To address these issues, an assessment will be carried out through field observations, leading to recommendations aimed at the conservation of snake species.
RESULTS
Snake species composition in the study sites
6.1.1 List of snakes from these three communes
During field surveys, a total of twenty-five specimens were collected, leading to the identification of 19 species across 16 genera and 5 families, namely Colubridae, Natricidae, Pareidae, Viperidae, and Xenodermatidae Notably, this study has documented 9 new snake species for the Van region.
In Ho District, three new snake species have been recorded in Moc Chau District, adding to the 32 species identified in previous studies by Nguyen et al (2009) and Nguyen et al (2010) This discovery increases the total number of snake species in the area to 42.
No Scientific name English name TX CK CT
1 Indotyphlops braminus (Daudin, 1803) Brahminy blind snake 2
2 Python bivittatus Kuhl, 1820 Burmese Python 1,2
III Xenopeltidae Bonaparte, 1845 Sunbeam snakes
3 Xenopeltis unicolor Reinwardt, 1827 Sunbeam Snake 1,2
IV Colubridae Oppel, 1811 Typical snakes
4 Ahaetulla prasina (Boie, 1827)* Asian vine snake 1, 2, S S, I
5 Boiga multomaculata (Boie, 1827) Many-spotted Cat Snake 1, 2
7 Coelognathus radiatus (Boie, 1827) Radiated Ratsnakes 1, 2 1 1
8 Dendrelaphis ngansonensis (Bourret, 1935)* Nganson Bronzeback S
9 Dendrelaphis pictus (Gmelin, 1789)* Painted Bronzeback S
10 Elaphe moellendorffi (Boettger, 1886) Flower Snake 2, I I I
11 Elaphe taeniura (Cope, 1861) Beauty Snake 1, P
12 Euprepiophis mandarinus (Cantor, 1842) Mandarin Ratsnakes 1, 2 I
13 Gonyosoma boulengeri (Mocquard, 1897)* Rhinoceros Snake S
14 Lycodon fasciatus (Anderson, 1879)* Banded Wolf Snake S 1
15 Lycodon futsingensis (Pope, 1928)* Futsing Wolf Snake 2, S
16 Lycodon ruhstrati (Fischer, 1886) Mountain Wolf Snake 1
17 Oligodon chinensis (Günther, 1888)* Chinese Kukri Snake S
18 Oreocryptophis porphyraceus (Cantor, 1839) Red Bamboo Snake 1, 2, S
19 Ptyas korros (Schlegel, 1837)* Chinese Ratsnake 2, S I I
20 Ptyas mucosa (Linnaeus, 1758) Oriental Ratsnake 1, 2
21 Amphiesma stolatum (Linnaeus, 1758) Buff Striped Keelback 2
22 Fowlea flavipunctatus (Hallowell, 1860) Yellow-Spotted Keelback 1, S 1, S 1
23 Hebius chapaensis (Bourret, 1934)* Vietnam Water Snake S
24 Rhabdophis chrysargos (Schlegel, 1837) Specklebelly Keelback 1, 2
25 Rhabdophis helleri (Schmidt, 1925)* Heller’s Red-necked
26 Trimerodytes percarinatus (Boulenger, 1899) Eastern Water Snake 1, 2, S
VI Pareatidae Romer, 1956 Slug snakes
27 Pareas carinatus Wagler, 1830* Keeled Slug Snake S 1
28 Pareas hamptoni (Boulenger, 1905)* Hampton's Slug Snake S
VII Homalopsidae Bonaparte, 1845 Freshwater snakes
29 Hypsiscopus plumbea (Boie, 1827) Rice Paddy Snake 1, 2 1 1
30 Myrrophis chinensis (Gray, 1842) Chinese Mud Snake 1
31 Psammodynastes pulverulentus (Boie, 1827) Common Mock Viper 1, 2
IX Elapidae Boie, 1827 Cobra, Krait, Coral snakes
32 Bungarus fasciatus (Schneider, 1801) Banded Krait 1, 2 I I
33 Bungarus multicinctus Blyth, 1861 Many-banded Krait 1, 2 I I
34 Naja atra Cantor, 1842 Chinese Cobra 1, 2 I I
35 Ophiophagus hannah (Cantor, 1836) King Cobra 2
36 Sinomicrurus macclellandi (Reinhardt, 1844) MacClelland’s Coral Snake 1, 2
37 Ovophis monticola (Günther, 1864) Chinese Mountain Pit Viper 2
38 Protobothrops mucrosquamatus (Cantor, 1839)* Brown spotted pitviper 1, S S
39 Trimeresurus albolabris Gray, 1842 White-lipped pitviper 2
40 Trimeresurus cf guoi Chen, Shi, Vogel & Ding,
41 Trimeresurus stejnegeri Schmidt, 1925 Chinese Green Tree Viper 1, 2
XI Xenodermatidae Gray, 1849 Strange-skinned snakes
42 Parafimbrios cf lao Teynié, David, Lottier, Le,
Note: 1: Nguyen et al 2009; 2: Nguyen at el (2010); this study including (S: specimen, I: interview, P: picture), * new record
The Colubridae family is the most diverse, comprising 17 species across 12 genera, including Ahaetulla, Boiga, and Dendrelaphis Following this, the Natricidae family features 6 species within 5 genera, such as Amphiesma and Rhabdophis The Elapidae family includes 5 species from 4 genera, including Bungarus and Naja Similarly, the Viperidae family consists of 5 species across 3 genera, such as Ovophis and Trimeresurus Lastly, the Homalopsidae family is represented by 2 species and 2 genera.
(including: Hypsiscopus, Myrrophis) Pareatidae with 2 species and 1 genus
(Pareas) Pythonidae with 1 species and 1 genus (Python), Xenopeltidae with
1 species and 1 genus (Xenopeltis), Pseudaspididae with 1 species and 1 genus (Psammodynastes), Xenodermatidae with 1 species and 1 genus (Parafimbrios), Typhlopidae with 1 species and 1 genus (Indotyphlops)
Figure 6.1 Snake diversity in three communes border with Laos by family and genera
18 number of species number of genera
Figure 6.2 Snake species from this study in comparison with previous document
6.1.2 New records of snakes in the study sites a) New records in Van Ho District
Nganson Bronzeback/ Rắn leo cây ngân sơn
Specimen examined (n=1): One dead adult female field number:
TX2.22.44 (20 0 40'103''N/104 0 42'493''E, elevation 797 m a.s.l) collected on June 21 st 2022 in Bun Village, Tan Xuan Commune by Tuong Sy Dinh and Vang A Mua
The specimen from Tan Xuan commune aligns with the morphological descriptions provided by Das (2010), Nemes et al (2013), and Vassilieva et al (2016), featuring a snout-vent length (SVL) of 880 mm and a tail length (Tal) of 430 mm It exhibits a robust body and a head that is distinct from the neck, measuring longer than wide with a head length (HL) of 26 mm and a head width (HW) of 16.5 mm Additionally, it has two loreal scales on each side (2/2).
The study by Nguyen et al (2009, 2010) provides detailed morphological data, noting that the species has a total of 1 preocular scale, 2 postocular scales, and 2 anterior and posterior temporals The supralabials consist of 9 scales, with the fourth to sixth in contact with the eye, and the seventh being the largest Additionally, there are 9 infralabials, with the first to fifth bordering the first chin shield The dorsal scale arrangement is characterized by 15-15-11 smooth rows, while the ventral scales total 183 The cloacal scale is divided, and there are 134 divided subcaudal scales.
Coloration in preservative: Dorsum bronze-brown, head have a black stripe present along both side of the head Ventral light bronze-brown
Ecological notes: The specimen was collected inside the funnel trap at
9:30 in the morning The surrounding habitat was stream, nature forest and rocky cave The relative temperature was about 29.3 0 C and the humidity was 60%
Distribution: In Vietnam, this species was known Ha Giang and Cao
Bang provinces in the North southwards to Quang Ngai Province Elsewhere, the species is recorded from: Laos, Thailand, China, Cambodia (Nemes et al
Figure 6.3 (A) Dorsal and (B) ventral views of Dendrelaphis ngansonensis (TX2.22.44) Photos by Tuong S Dinh
Common Bronze-back/ Rắn leo cây thường
Specimen examined (n=1): One dead adult female field number:
TX2.22.06 (20 0 38'790''N/104 0 43'109''E, elevation 514 m a.s.l) collected on June 11 th 2022 in Bun Village, Tan Xuan Commune by Vinh Quang Luu
Morphological characters: The specimen from Tan Xuan commune agreed with the descriptions of Das (2010) and Vassilieva et al (2016): SVL
The specimen measures 730 mm in total length, with a tail length of 370 mm It features a robust body and a distinct head separate from the neck The supralabials consist of 10 scales, with the fourth to sixth in contact with the eye and the seventh being the largest The infralabials also have 10 scales, with the first to fifth bordering the first chin shield The dorsal scales are arranged in 15-15-11 rows and are smooth, while the ventral scales total 175 The cloacal scale is divided, and there are 129 divided subcaudal scales.
Coloration in preservative: Dorsum bluish, cream ventrolateral stripe edged with black along flanks, head have a black stripe present along both side of the head Ventral light bronze-brown
Ecological notes: The specimen was accident and collected on the road at 14:00 The surrounding habitat was residential area and milpa The relative temperature was about 29.9 0 C and the humidity was 62%
Distribution: In Vietnam, this species was known Dien Bien and Lao
The Cai provinces in southern Vietnam include An Giang, Kien Giang, and Ca Mau (Pham et al 2013) Additionally, this species has been documented in various countries across Asia, such as India, Nepal, Bangladesh, China, Brunei, Myanmar, Laos, Thailand, Cambodia, Malaysia, Singapore, Indonesia, and the Philippines (Nguyen et al 2009, Uetz et al 2022).
Figure 6.4 (A) Dorsal and (B) ventral views of Dendrelaphis pictus
(TX2.22.06) Photos by Tuong S Dinh
Specimen examined (n=1): One dead adult female field number:
TX2.22.36 (elevation 450 m a.s.l) collected on June 17 th 2022 in Bun Village, Tan Xuan Commune by Vang A Mua
The specimen from Tan Xuan commune aligns with the morphological descriptions provided by Smith (1943), Nguyen Van Sang (2007), and Das (2010), featuring a snout-vent length (SVL) of 670 mm and a tail length (TaL) of 265 mm It exhibits a slender, slightly compressed body, with a head length (HL) of 24.4 mm and a head width (HW) of 11.81 mm, distinctly separated from the neck The specimen has one loreal scale on each side, not in contact with the eyes, one preocular scale, two postocular scales, two anterior temporals, and two to three posterior temporals Additionally, it has nine supralabials, with the fourth and sixth in contact with the eye, and ten infralabials, where the first to fifth border the first chin shield The dorsal scales are arranged in 19-19-13 rows and are smooth, while the ventral scales total 219, with a divided cloacal scale and 136 divided subcaudal scales.
Coloration in preservative: Dorsum pale green; interstitial skin on sides of body dark blue and white; white line on lower flanks; venter pale green
Ecological notes: The specimen was collected on the tree branch at
9:00 The surrounding habitat was residential area and rice field
Distribution: In Vietnam, this species was known from Son La, Thai
Nguyen, Vinh Phuc, Ha Noi, Quang Ninh, Hai Phong, Ha Tinh provinces Elsewhere, the species is recorded from China (Nguyen et al 2009)
Figure 6.5 (A) Dorsal and (B) ventral views of Gonyosoma boulengeri
(TX2.22.36) Photos by Tuong S Dinh
Banded Wolf Snake/ Rắn khuyết đốm
Specimen examined (n=1): One adult male, field number: TX.22.05
(20 0 38'249''N/104 0 43'286''E, elevation 489 m a.s.l) collected on May 18 th
2022 in Bun Village, Tan Xuan Commune by Tuong Sy Dinh and Ha Trung Duc
The specimen from Tan Xuan commune aligns closely with the descriptions provided by Nguyen Van Sang (2007), Das (2010), and Luu et al (2019), featuring a snout-vent length (SVL) of 580 mm and a tail length (Tal) of 140 mm It exhibits a slender, subcylindrical body and a flattened head that is longer than wide, with a head length (HL) of 17.8 mm and a head width (HW) of 11.5 mm, distinctly separated from the neck The specimen has one loreal scale touching the eye, one preocular scale, two postocular scales, two anterior temporals, and two posterior temporals It possesses eight supralabials, with the third to fifth in contact with the eye and the seventh being the largest, as well as eight or nine infralabials that border the chin shields The dorsal scale rows are arranged in a pattern of 17–17–15 with keels, totaling 202 ventral scales, a single cloacal scale, and 61 divided subcaudal scales.
The coloration of this species features a glossy black dorsum adorned with 27 irregular cross-bars on the body and 12 on the tail Its belly displays a white pattern interspersed with dark transverse blotches, while the venter exhibits alternating dark and white cross-bars on both the ventral surface and the tail.
Ecological note: The specimen was found at 21:15 on the forest ground The surrounding habitat was stream, shrub and bamboo forest The relative temperature was about 27°C and the humidity was 60%
Distribution: In Vietnam, this species was reported from Lai Chau,
The species is found in several provinces in Vietnam, including Lao Cai, Son La, Cao Bang, Vinh Phuc, Hai Duong, Ha Tinh, Quang Binh, and Kon Tum Additionally, it is also present in other countries such as India, China, Myanmar, Laos, and Thailand (Nguyen et al 2009).
Figure 6.6 (A) Dorsal and (B) ventral views of Lycodon fasciatus
(TX.22.05) Photos by Tuong S Dinh
Chinese Kukri Snake/ Rắn khiếm trung quốc
Specimen examined (n=1): One adult female, field number: TX2.22.40 (20 0 40'103''N/104 0 42'493''E, elevation 797 m a.s.l) collected on June 18 th 2022 in Bun Village, Tan Xuan Commune by Tuong Sy Dinh and Vang A Mua
The specimen from Tan Xuan commune aligns closely with the descriptions provided by Das (2010), Hecht et al (2013), Ziegler et al (2014), and Gawor et al (2016), featuring a snout-vent length (SVL) of 510 mm and a tail length (Tal) of 120 mm It exhibits a robust, subcylindrical body with a short head that is longer than wide (head length HL 17.8 mm, head width HW 10.6 mm), seamlessly transitioning into the neck The loreal scale is square-shaped and not in contact with the eye, with a configuration of 1/1 The specimen has 2/2 preoculars, 2/2 postoculars, 1/1 anterior temporals, and 1/1 posterior temporals The supralabials total 7/7, with the third and fourth in contact with the eye, and the seventh being the largest Additionally, there are 8/8 infralabials, with the first to fourth bordering the chin shields The dorsal scale rows consist of 17–17–15, are smooth, and the ventral scales number 177 The cloaca is single, and there are 57 divided subcaudals.
The dorsal surface is brown, featuring 12 distinct reddish-brown spots on the body and three on the tail, along with a black band extending from one eye to the other and a V-marking behind the head The ventral side is white, adorned with squarish spots along the outer margins of the ventrals.
Ecological notes: The specimen was collected inside the funnel trap at
14:30 The surrounding habitat was stream, nature forest and rocky cave The relative temperature was about 29.3 0 C and the humidity was 64%
Distribution: In Vietnam, this species was known from Lao Cai, Ha
The species is found in several provinces including Giang, Bac Kan, Lang Son, Vinh Phuc, Quang Ninh, Bac Giang, Hai Phong, Hai Duong, Nghe An, Ha Tinh, Quang Binh, and Gia Lai Additionally, it has been recorded in China (Nguyen et al 2009, Hecht et al 2013, Ziegler et al 2014).
Figure 6.7 (A) Dorsal and (B) ventral views of Oligodon chinensis
(TX2.22.40) Photos by Tuong S Dinh Family Natricidae Bonaparte, 1838
Vietnam Water Snake/ Rắn bình mũi sapa
Specimen examined (n=1): One adult female, field number: TX2.22.30 (20 0 38'692''N/104 0 43'648''E, elevation 417 m a.s.l) collected on June 15 th 2022 in Bun Village, Tan Xuan Commune by Tuong Sy Dinh and Vang A Mua
The specimen from Tan Xuan commune aligns closely with the descriptions provided by Luu et al (2020) and David et al (2021), featuring a snout-vent length (SVL) of 385 mm and a tail length (Tal) of 180 mm It exhibits an elongated body that is slightly laterally compressed, with a head that is elongated and longer than it is wide, measuring 14 mm in head length (HL) and 8 mm in head width (HW), and is slightly distinct.
Distribution of snake species across habitat types and elevations in the
At elevations between 400 and 600 meters, a total of 8 species belonging to 8 genera and 4 families were recorded Notable species include the Asian vine snake (Ahaetulla prasina), Painted Bronzeback (Dendrelaphis pictus), Rhinoceros Snake (Gonyosoma boulengeri), and Banded Wolf Snake (Lycodon fasciatus).
Yellow-Spotted Keelback (Fowlea flavipunctatus), Vietnam Water Snake (Hebius chapaensis), Keeled Slug Snake (Pareas carinatus), Guo’s green pit viper (Trimeresurus cf guoi)
At elevations between 600 and 800 meters, a total of 10 snake species belonging to 10 genera and 4 families have been documented These include the Asian vine snake (Ahaetulla prasina), Collared Reed Snake (Calamaria pavimentata), Nganson Bronzeback (Dendrelaphis ngansonensis), Chinese Kukri Snake (Oligodon chinensis), Red Bamboo Snake (Oreocryptophis porphyraceus), Chinese Ratsnake (Ptyas korros), Heller’s Red-necked Keelback (Rhabdophis helleri), Brown spotted pit viper (Protobothrops mucrosquamatus), Guo’s green pit viper (Trimeresurus cf guoi), and Laotian bearded snake (Parafimbrios cf lao).
At elevations between 800 and 1000 meters, five species belonging to four families and five genera were recorded These species include the Futsing Wolf Snake (Lycodon futsingensis), the Yellow-spotted Water Snake (Fowlea flavipunctatus), the Black-striped Flower Snake (Trimerodytes percarinatus) with two individuals observed, the Hamptoni Rat Snake (Pareas hamptoni), and the Green Tree Viper (Protobothrops mucrosquamatus).
According to the elevation classification by Bain and Hurley (2011), there are 19 species, comprising 14 genera and 5 families, found below 800 m, while above 800 m, there are 7 species belonging to 4 families and 6 genera.
Most of species distribution in the elevation range from 600 - 800 m
Trimeresurus cf guoi is the species that have elevation distribution in both of below 800 m and above 800 m
Figure 6.23: Number of species distribution by elevation ranges
Figure 6.24: Number of family and species distribution by elevation ranges
The figure illustrates the distribution of three snake families—Colubridae, Natricidae, and Viperidae—across all elevation types Additionally, the Pareatidae family is present at elevations of 400-600 m and 800-1000 m, while the Xenopeltidae family is exclusively found at elevations between 600-800 m.
According to the UNESCO vegetation classification from 1973 and the assessment of human impact on vegetation cover outlined in the "Manual Notebook for Biodiversity Survey and Monitoring" (2003), we categorized the current forest status in three areas into five distinct habitat types: stream, hill + milpa, residential area, bamboo forest, and natural forest.
The initial habitat surveyed was a stream, where we identified a total of 7 species across 7 genera The species documented in this habitat include the Asian vine snake (Ahaetulla prasina) with 3 individuals, the Chinese ratsnake (Ptyas korros), the Vietnam water snake (Hebius chapaensis), Guo’s green pit viper (Trimeresurus cf guoi), and the keeled slug.
Snake (Pareas carinatus), Heller’s Red-necked Keelback (Rhabdophis helleri) and Brown spotted pitviper (Protobothrops mucrosquamatus)
The second habitat, a mix of hill and milpa, yielded a total of 6 species across 6 genera Notable species recorded include the Eastern Water Snake (Trimerodytes percarinatus) with 2 individuals, the Futsing Wolf Snake (Lycodon futsingensis), the Rhinoceros Snake (Gonyosoma boulengeri), Guo’s green pit viper (Trimeresurus cf guoi), and the Brown spotted pit viper.
(Protobothrops mucrosquamatus) and Laotian bearded snake (Parafimbrios cf lao)
The third habitat was residential areas In this habitat, we recorded 2 species with 2 generaincluding: Yellow-Spotted Keelback (Fowlea flavipunctatus – 2 individuals), Nganson Bronzeback (Dendrelaphis ngansonensis)
The fourth habitat was bamboo forest We recorded 2 species with 2 genera Species recorded in this habitat are: Collared Reed Snake (Calamaria pavimentata) and Banded Wolf Snake (Lycodon fasciatus)
The fifth habitat, the nature forest, was home to four species across four genera, including the Chinese Kukri Snake (Oligodon chinensis), Hampton's Slug Snake (Pareas hamptoni), Red Bamboo Snake (Oreocryptophis porphyraceus), and Painted Bronzeback (Dendrelaphis pictus).
Figure 6.25: Number of family and species distribution by habitats
Based on the record position on the field, we divided the position of snakes in 4 forms: on the ground, road, under the stream and on the tree branch
The results indicate that there were 9 species located on tree branches, 12 species found on the ground (including 4 species captured in funnel traps), 2 species observed on the road (with 1 instance of roadkill), and 2 species identified underwater.
Stream Hill + milpa Residental area Bamboo forest Nature forest number of species number of genera
The Eastern Water Snake (Trimerodytes percarinatus) has been observed in both aquatic and terrestrial environments Similarly, the Brown Spotted Pit Viper (Protobothrops mucrosquamatus) and Guo’s Green Pit Viper (Trimeresurus cf guoi) inhabit ground and tree branches Notably, our research documented three individuals of the Asian Vine Snake (Ahaetulla prasina) exclusively on tree branches during nighttime, indicating specific behavioral patterns among these species.
Ahaetulla prasina is primarily arboreal, with survey results indicating that its main microhabitats are found both on the ground and on tree branches.
Figure 6.26 Graph show the number of species distribution in
Conservation issues
The article examines snake species with conservation status in three communes, comparing them to existing national and international legal frameworks, including the Vietnam Red Data Book (RBVN, 2007) and the IUCN Red List.
Ground Tree branch Road Under water
Threatened Species – IUCN (2022), Governmental Decree No 84/2021/ND-
CP – Decree 84 (2021) Species distributed only in Vietnam are endemic and conserved
Table 6.2 List of threatened species
No English name Scientific name RBVN
1 Burmese Python Python bivittatus CR IIB VU
2 Radiated Ratsnakes Coelognathus radiatus VU
3 Flower Snake Elaphe moellendorffi VU VU
4 Beauty Snake Elaphe taeniura VU
5 Mandarin Ratsnakes Euprepiophis mandarinus VU
6 Red Bamboo Snake Oreocryptophis porphyraceus VU
7 Chinese Ratsnake Ptyas korros EN NT
8 Oriental Ratsnake Ptyas mucosa EN IIB
9 Banded Krait Bungarus fasciatus EN
10 Chinese Cobra Naja atra EN IIB VU
11 King Cobra Ophiophagus hannah CR IB VU
Note: Decree 84 (2021) = Decree No 84/2021/ND-CP dated September 22,
In 2021, the Government amended Decree No 06/2019/ND-CP, which focuses on the management of endangered, precious, and rare forest plants and animals, aligning with the Convention on International Trade in Endangered Species of Wild Fauna and Flora This decree categorizes species into two groups: Group IB includes forest fauna threatened with extinction, prohibiting their commercial exploitation, while Group IIB consists of species not currently endangered but at risk without strict regulatory measures The Vietnam Red Data Book (RBVN, 2007) provides descriptions of nationally endangered wild animal species, highlighting those classified as Critically Endangered (CR) and Endangered (EN).
Endangered, VU = Vulnerable; IUCN (2022) = The IUCN Red List of Threatened Species ver 2021.3 CR = Critically Endangered, EN = Endangered, VU = Vulnerable, LR/nt = Lower Risk/Near Threatened
This research identified 11 threatened snake species, including 6 listed in the IUCN Red List of Threatened Species (2022) The Burmese Python (Python bivittatus), Flower Snake (Elaphe moellendorffi), Beauty Snake (Elaphe taeniura), Chinese Cobra (Naja atra), and King Cobra (Ophiophagus hannah) are classified as Vulnerable (VU), while the Chinese Ratsnake (Ptyas korros) is categorized as Near Threatened (NT) Additionally, 10 snake species are included in the Vietnam Red Data Book (2007), with the Burmese Python and King Cobra listed as Critically Endangered (CR) Other species such as the Radiated Ratsnake (Coelognathus radiatus), Flower Snake, Mandarin Ratsnake (Euprepiophis mandarinus), and Red Bamboo Snake (Oreocryptophis porphyraceus) are classified as Vulnerable (VU), while the Chinese Ratsnake, Oriental Ratsnake (Ptyas mucosa), Banded Krait (Bungarus fasciatus), and Chinese Cobra are categorized as Endangered (EN) Furthermore, 4 species are recognized in the Government’s Decree No 84/2021/ND-CP dated September 22, 2021.
The government is amending Decree No 06/2019/ND-CP, which regulates the management of endangered, precious, and rare forest plants and animals, as well as the implementation of the Convention on International Trade in Endangered Species of Wild Fauna and Flora Notably, the Burmese Python (Python bivittatus), Oriental Ratsnake (Ptyas mucosa), and Chinese Cobra (Naja atra) are classified as threatened in group IIB, indicating they are not currently at risk of extinction but require strict control to prevent future threats due to commercial exploitation In contrast, the King Cobra (Ophiophagus hannah) is categorized in group IB, which includes species that are threatened with extinction and are prohibited from commercial use, as outlined in CITES Appendix I.
6.3.2 Threat to snake fauna in the study site
The habitat of snakes has been narrowed, divided and degraded due to activities of deforestation for milpa, cattle grazing, quarrying, construction
Deforestation for milpa is a prevalent practice among local communities in the three communes, where shifting cultivation is the primary livelihood This clearing of evergreen forests not only leads to the direct death of various snake species and their prey during the burning process but also depletes water sources and disrupts the natural habitats essential for snake survival.
Figure 6.27 Milpa in Tan Xuan Commune
Figure 6.28 Milpa in Chieng Khua Commune
During a field survey in Bun village of Tan Xuan commune and Ong Ly village of Chieng Khua commune, I observed local residents grazing buffaloes, cows, and horses This cattle grazing significantly impacts snake habitats by destroying shrubs and weeds, hindering forest recovery after milpa, and causing environmental pollution, particularly in areas where buffaloes congregate The herding behavior of cows leads to the pollution of natural puddles in the evergreen forest, as buffaloes bathe and discharge waste, severely affecting the local snake population.
Traffic accidents: Although there are no specific statistics, but it is easy to see dead snakes on the road because of roadkill
Figure 6.29 One adult Dendrelaphis pictus dead on road by road kill
Many locals express a fear of venomous snakes, leading them to kill any snake they encounter, despite the fact that many species are non-venomous and pose no threat to humans This widespread reaction not only reflects their fear but also threatens the snake population.
Figure 6.30 One adult male Trimeresurus cf guoi dead on the mipla by human kill in Tan Xuan commnune Photo by Tuong S Dinh
Figure 6.31 One adult Dendrelaphis pictus dead on road by human kill
Figure 6.32 One adult Elaphe taeniura dead on the road by human kill in
Chieng Khua commnune Photo by Thinh L Nghiem
Solutions for conservation and management of snake fauna in the
Priority should be given to the conservation of endangered and rare snakes listed in Decree 84 of the Government (2021), the Vietnam Red Book
The IUCN Red List (2022) highlights several critically endangered (CR) and endangered (EN) species, including the Burmese Python (Python bivittatus), Chinese Ratsnake (Ptyas korros), Oriental Ratsnake (Ptyas mucosa), and Banded Krait (Bungarus fasciatus) It is crucial to prioritize conservation efforts for these threatened species.
Based on the practical situation and assessment of the impact factors above, we propose some solution for the conservation of snakes in these three communes:
- Increasing and maintaining activities of forest patrolling is important and necessary to reduce the impact on forest to protect the habitat of wildlife specially is snakes
The collaboration among police, border guards, forest rangers, and local authorities has intensified inspections to curb deforestation activities associated with milpa farming.
- Priority area: Bun & Lay village (Tan Xuan Commune), Ong Ly village (Chieng Khua Commune), Pa Khom village (Chieng Tuong Commune)
- Patrolling time: Summer season, from May to July (milpa and rice paddy field season)
- Focus on improving the capacity and understanding about biological resources of the staff in the communes, thereby improving the quality of supervision and propaganda to local people
Develop community education programs focused on biodiversity and conservation to raise awareness about the importance of protecting snakes This can be achieved by showcasing specimens and images of various species in the park, emphasizing the need to avoid killing or crushing snakes on the road.
- Priority area: Bun & Lay village (Tan Xuan Commune), Ong Ly village (Chieng Khua Commune), Pa Khom village (Chieng Tuong Commune)