«An assessment of the collection and trade of amphibians in Cambodia July 2010 This report was a joint initative between Fauna & Flora International ...»
Fauna & Flora International
An Investigation into Frog Consumption
and Trade in Cambodia
Species, Habitats and Ecosystems Team
An assessment of the
collection and trade of
amphibians in Cambodia
This report was a joint initative between Fauna & Flora International and
The Angkor Centre for Conservation of Biodiversity.
Prepared by Neang Thy & Toby Eastoe. Species, Habitat and Ecosystems team.
Fauna & Flora International Cambodia Programme 32, Street 282, Bong Keng Kong I Phnom Penh.
Tel: 023 220 534 Email: firstname.lastname@example.org Suggested citation:. Neang, T. 2010. An Investigation into Frog Consumption and Trade in Cambodia. Fauna & Flora International Cambodia Programme.
1. Introduction 3
2. Methods and materials 5
3. Results 5 3.1: Species collected for consumption 5 3.2: Local consumption 8 3.3: Methods used by the collectors 8 3.4: Frog trading 9 3.5: International trade 10 3.6: Estimated quantity brought to markets in Phnom 11 3.7: Value chain and income generation from frogs 12 3.8: Frog Farming 13
4. Conclusion 18
5. Recommendations 19
6. References 20 Appendix I 23 List of Plates Plate 1. Hoplobatrachus rugulosus 7 Plate 2. Fejervarya limnocharis 7 Plate 3. Glyphoglossus molossus 7 Plate 4. Kaloula pulchra 7 Plate 5. Rana lateralis 7 Plate 6. Bufo melanostictus 7 Plate 7. Wooden gill trap 8 Plate 8. Harpoon guns for frog catching 9 Plate 9. Dried Fejervarya along national highway 10 Plate 10. Kangkeb-bauk stall along national highway 10 Plate 11. Skinned Hoplobatrachus in Phnom Penh market 12 Plate 12. Hoplobatrachus cf. in Takeo frog farm 14 Plate 13. Frog farm in Takeo 15 Plate 14. Neang Thy at Takeo frog farm 15 Pla
Report for The Angkor Centre for Conservation of Biology By: Fauna & Flora International Cambodia Programme: Species, Habitats & Ecosystems team.
1. Introduction Amphibians globally are facing a growing crisis, with between a third and one half of all known species threatened with extinction (Stuart et al., 2004; Attenborough, 2008). Although new amphibian species are being discovered and described every year, with 6433 species currently recognised worldwide (Frost, 2009) recent studies have shown that amphibian populations are drastically declining across the planet. This fact has lead to concern within the conservation community and prompted a number of initiatives aimed at highlighting the problem. The International Union for Conservation of Nature decided to declare 2008 the “Year of the Frog”; while the World Association of Zoos and Aquariums established the “Amphibian Ark” – an initiative to start a captive breeding programme for the most threatened species. The major causes of amphibian decline are varied. Human activities such as habitat destruction, pollution, and over-harvesting for food have seriously impacted certain species;
while natural problems like the recent outbreak of chytrid fungus Batrachochytrium dendrobatidis and climate change (both exacerbated by human activities) have caused the extinction of many species (Stuart et al., 2004; Hopkins, 2007; Rowley et al., 2009).
The consumption of frogs worldwide and the impact it has on harvested populations has been well documented in some cases. Over-collection of Rana draytonii during the Californian gold rush of 1849 caused a significant depletion in the abundance of this species within 20 years (Jennings and Hayes, 1985). A similar fate has befallen the Indian bullfrog Rana tigrina, another large-bodied species that is harvested for human consumption. In China a ban on harvesting this frog was imposed after over-collecting resulted falling frog numbers but a reciprocal increase in the agricultural insect pests on which this frog feeds (Fugler, 1985).
Harvesting of amphibians is often associated with the rural poor supplementing their diet with any available protein. However, the trade in frogs particularly is a worldwide business. Legs of bullfrogs from Asia, mainly Indonesia, Bangladesh, India and Malaysia are exported to Europe as a gastronomic delicacy. In the Southeast Asian region, Indonesia has historically been the largest exporter of frog’s legs (Warkentin et al., 2009) with 5,600 tons exported in 1992 (Kusrini and Alford, 2006); while in 1981 alone India exported an estimated total of 4,368 tons (http://www1.american.
edu/ted/frogs.htm). It is reported that 6,000 tons of frog legs were imported to Europe each year during the 1990s (Jensen and Camp, 2003) – a figure which rose to 9700 tons in 1999. The chief importers were Belgium, Luxembourg and France (Warkentin et al., 2009; Patel, 1993; Teixeira et al., 2001). Currently the United States is reported to import more than 3000 tons of frog meat a year from abroad (http://amphibiaweb.org/) and harvested 5200 tons of wild caught frogs internally between 1998 and 2002 (Martin et al., 2005). Between 1981-1984, over 6 million rugulose frogs Hoplobatrachus rugulosus, presumably caught from the wild, were exported from Thailand to Hong Kong (Wai-Neng Lau et al., 1999). Such large numbers is likely to be causing an adverse effect among both frog populations and the ecosystems of which they are a fundamental part.
3 Trade in frogs is not restricted to meat. Frogs are also being caught for use in making novelties and curios for the tourist industry such as purses and key chains. Frog skin is used in the leather and glue trade (Pough et al., 1998) and in Sumatra, the depletion of a giant Limnonectes species to make stuffed ornaments is directly attributable to over collecting (Holden, pers. com.). Frogs also have medicinal value: in China thirty two species are recognised as components of traditional Chinese medicine (Carpenter et al., 2007) cited from (Ye et al., 1993) (Pough & Ye, 1993) It is estimated that between 180 million to a billion frogs are currently collected from the wild in Asia alone each year (www.amphibiaweb.org/declines/exploitation.html). While the frog trade has raised concern related to the decline of certain frog populations around the world, the industry has not been properly monitored. To supplement the higher demand for frogs, and to counteract the effects of over-harvesting, some countries have introduced frog farming. Although this initiative may reduce pressure on wild populations, it comes with additional risks: the introduction of non-native and potentially harmful exotic species, and facilitating the spread of chytrid fungus (Jennings and Hayes, 1985).
Frog consumption among local people in Cambodia is widespread, and many communities still depend on collecting frogs to either supplement their limited protein intake or generate additional income (Allen et al, 2008). But the situation remains poorly documented due to a lack of research in the subject. Herpetological studies in Cambodia have been focussed on taxonomic and systematic work (Ohler et al., 2002; Stuart et al., 2006a, 2006b; Grismer et al., 2007a, 2007b, and 2008) with few if any ecological studies. Nao Tuok et al., 2001 did tackle the subject of frog trade, reporting that officially 15 tons of frogs were exported in the past few years, but without stating where these frogs were going, or what species were being collected. If this is an official figure, then the true scale of export from Cambodia is likely to be considerably higher.
The lack of reliable data on this subject from Cambodia is clearly a concern. This report is an initial attempt to address the issue of frog consumption and trade status and how it may have affected local amphibian populations. The information presented aims to be a reference for developing a regional amphibian assessment and will be useful in seeking regional cooperation in developing an action plan to ensure that amphibians are harvested sustainably in Cambodia.
The specific aims of this report are to:
• Identify species collected for local consumption,
• Assess the extent of trade within Cambodia,
• Assess the extent of export from Cambodia,
• Assess whether the current collection volume is sustainable,
• Assess the importance of the income generated from frog harvesting,
• Determine the possible threats arising from collection activities,
• Investigate the status of frog farming in Cambodia and identify farmed species,
• Recommend a strategic plan to monitor the volume of consumption and exports.
Surveys were based on interviews with local participants in the frog trade. These were planned to coincide with the onset of the rainy season May, June and July 2009. This period represents peak activity in both frog populations and harvesting. Initial research was carried out in Takeo, Kampong Speu and Kampong Chhang provinces, and the markets and restaurants of Phnom Penh. A follow up survey investigated the north-western areas bordering Thailand including parts of Battambang, Siem Reap, Banteay Meanchey, and Oddar Meanchey provinces.
The survey team travelled by motorbike and taxi to and around the survey sites. Interviews were conducted across a broad spectrum of locales. In rural areas, local collectors and villagers;
permanent frog sellers along national highways no.2, no.3, no.4 and no.5; frog vendors in provincial market towns; customs officials at the Cambodia-Thailand border; frog middlemen and frog retail sellers in major towns and markets; and restaurant owners in Phnom Penh. Visits were also made to a government vocational training centre in Battambang, which teaches frog farming techniques to local communities, and a frog farm in Takeo province. A standard questionnaire was used for interviews (see annex I).
3.1. Species collected for consumption Throughout Cambodia frogs are collected as a food source, and at some time or other, most species are probably gathered for human consumption. Rural communities living near forests will opportunistically utilize frog protein, especially the larger species, such as riverine Ranids and the IUCN listed spine-glanded mountain frog Quasipaa fasciculispina. This type of collecting, although it may be responsible for localized depletion of certain species, is potentially of minimal threat to native amphibian populations. Of greater concern is the wholesale collecting of the larger species found in agricultural landscapes that constitute the bulk of frogs harvested in Cambodia.
A total of six frog species were reportedly harvested on a regular basis for local consumption and
trade (Table 1). In decreasing order of reported volume the species collected were as follows:
Rugulose frog Hoplobatrachus rugulosus (Plate 1) paddy frog Fejervarya limnocharis (Plate 2) truncate-snouted frog Glyphoglossus molossus (Plate 3) Asian bullfrog Kaloula pulchra (Plate 4) Kokarit frog Rana lateralis (Plate 5) and black-spined toad Bufo melanostictus (Plate 6).
Rugulose frog Hoplobatrachus rugulosus. This species is one of the largest found in Cambodia, reaching up to 120 mm in length. They live in agricultural as well as natural environments, and are particularly suited to living around villages. These characteristics make this species one of the most popular for consumption and trade. The Khmer dish Kangke-bauk is made from this species, and it is prized by restaurateurs in Phnom Penh, appearing on the menus of premier restaurants in the capital. Hoplobatrachus has a wide distribution across Southeast Asia and is not currently threatened. However, over-collection could easily change that status, and this is a species that needs monitoring within the region.
Paddy frog Fejervarya limnocharis. An abundant, but small species that ranges across Southeast Asia that utilizes a variety of standing water sources to breed. Fejervarya is valued as a snack frog, often served on sticks as an accompaniment to rice wine. This species can be collected throughout the year. The nature of the Cambodian landscape, with vast areas of the country inundated by the swelling waters of the Tonle Sap, mean that this species is unlikely to suffer depletion from overcollecting.
5 Truncate-snouted bullfrog Glyphoglossus molossus. This unusual frog is perhaps one of the ugliest in Cambodia, but is also reported to be the most delicious, making it highly sought after. Records of frog distribution within Cambodia are still patchy, but this species appears to be restricted to the north western part of the country. Glyphoglossus is a fossorial species, spending most of its life unground or hidden beneath leaves, emerging to breed en masse only after periods of heavy rain.
Given its habit of explosive breeding, large numbers of these frogs can be collected after the first heavy rains of the monsoon. According to interviewees, these frogs are often prepared in a similar way to the fermented fish paste known locally as Phaork in order to preserve the meat for longer periods. The sale of this species can be seen in the markets of Siem Reap (Handschuh pers. com.) and newspaper reports from 2007 describe it as being traded with neighbouring Thailand. IUCN has given this species a Near Threatened designation, reflecting the fact that over-collection in Thailand especially, has caused the mean size of adults frogs to shrink by 30% over the past decade (IUCN, 2010). Given its regionally endemic status, and restricted range within Cambodia, coupled with its over-collection in Thailand, this species requires special attention in Cambodia.
Asian bullfrog Kaloula pulchra is also a popular edible species. As with Glyphoglossus, it spends most of its life underground, emerging after heavy rain. Locals consume this species when only small numbers of frogs are caught. When larger volumes are taken at the onset of the monsoon, or after periods of heavy rain, they are taken for sale in provincial market towns. Kaloula pulchra has a wide distribution across Southeast Asia and is unlikely to become threatened in the near future.
A similar species, Kaloula mediolineata has recently been found in Cambodia (Thy pers. obs.) and appears to be restricted to the northwest of the country. This frog may also be a subject of collection, and given its restricted range is of greater conservation interest.
Kokarit frog Rana lateralis. A pretty species that seems to occur only north of the Mekong river and is collected in small amounts during the wet season in Snoul district of Kratie province for local consumption (Khou Eang Hourt pers. com.).