Proposal: Aiming for maximum sustainability in the harvest of live monitor lizards in Ghana

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1 Proposal: Aiming for maximum sustainability in the harvest of live monitor lizards in Ghana Daniel Bennett Introduction This project aims to improve the quality and sustainability of Ghana s exports of live Varanus lizards. Ranching and captive breeding protocols for African monitor lizards are very poorly defined. Captive breeding of Varanus in Ghana has the potential to provide high quality captive bred offspring for export, and improved husbandry methods would allow protocols to be established for successful ranching of the species. Projects proposed: 1. Explore possibility of creating a prototype farm for the sustainable production and ranching of Varanus lizards. 2. Develop and evaluate methods for temporary housing of juvenile Varanus at high densities. 3. Develop and evaluate methods for husbandry of gravid female Varanus and incubation of their eggs. 4. Investigate the potential for identifying sex in hatchling Varanus lizards. Rational If sustainable captive breeding of Varanus lizards occurs in wildlife trade it has not been documented. This project aims to investigate the feasibility of farming Varanus lizard in Ghana, a major exporter of live V. exanthematicus and V. niloticus for wildlife trade, and improve viability of exported Varanus lizards through improved husbandry and incubation techniques. Introduction Almost quarter of a million live V. exanthematicus were traded internationally between 2008 and 2015 (Figure 1). Five countries within the range of the species reported total exports of 239,237 live animals in that period (Table 1). Almost all animals come from Ghana (66.8%) Benin (15.1%) and Togo (14.6%), with smaller numbers from Mali and Niger. CITES records indicate that about 35% of V. exanthematicus exported from West Africa are declared of ranched or captive bred origin and suggest that the quantity of wild caught animals from Togo and Benin in wildlife trade is minimal as a result (Table 2). However no information is available about the ranching or captive breeding operations since the investigations of de Buffrenil (1993) who did not consider operations he examined to be sustainable.

2 Since 2008 Ghana has reported imports of 12,185 captive bred or ranched V. exanthematicus from Benin and Togo for re-export, accounting for 7.6% of overall exports of the species and 87% of all Ghana s captive bred and ranched exports. Of almost 160,000 specimens exported from Ghana between 2008 and 2015, 88.5% were wild caught. Of the 11.5% of exports declared as captive bred (9.3%) or ranched (2.2%), only 1.5% were captive bred (0.3%) or ranched (1.2%) in Ghana. Since 2003 Ghana has also reported exports of 17,685 live Varanus niloticus, 82% of which originated from Benin (almost all declared ranched or captive bred) with smaller numbers of ranched animals from Togo and Mali. Only 580 live V. niloticus were of Ghanian origin (based on blank origin entries in CITES database), 440 of which were recorded as captive bred. Current taxonomy is poorly understood, with V. niloticus demonstrated to be a cryptic species complex with a distinct West African population that split around 5 million years ago (Dowell et al. 2015). No similar investigations have been conducted on other African species of Varanus. Captive breeding of Varanus lizards At present almost all Varanus breeding is carried out by private individuals in Europe, USA and Australia on a relatively small scale and involving species from at least five subgenera (Odatria, Soterosaurus, Varanus, Polydaedalus, Hapturosaurus) that have been established through multiple generations. Most species bred in captivity are high value (>$300) animals, often species difficult or illegal to obtain from the wild but also species regularly available as wild caught (V. salvator spp.) which are bred for unusual patterns and docile dispositions and typically have a value >$1000. However captive reproduction has been reported very rarely in V. exanthematicus and V. niloticus. Reproductive females rarely, if ever, survive two years and no captive bred populations of the animals exists. The very low retail value of the species (typically $25 for a juvenile) and abundance of specimens in trade means that there is no financial incentive to breed the animals unless they are of unusual appearance. Unpigmented specimens of both species have been sold for very high prices, presumably because of the financial incentive to propagate the animals, but none of these attempts have been successful to date. Ghana s monitor lizards would be ideal species to farm because they are highly fecund, can grow rapidly and of considerable economic importance throughout the continent. In captivity all recognised species of Polydaedalus monitor lizards are known to be capable of producing multiple clutches of eggs per year, and be capable of extremely high growth rates (to 1.3m total length within a year for both V. niloticus and V. exanthematicus). Early sexually maturity (circa. 7 months) has been claimed for V. albigularis but is undocumented in literature. Both species are have very high reproductive output, laying large clutches of small eggs that develop relatively quickly, with clutch sizes of almost 50 eggs for V. exanthematicus (Cisse 1980) and up to 60 eggs for V. niloticus (de Buffrenil & Rimbolt-Baly 1999). V. exanthematicus is capable of producing three clutches of eggs

3 in two months and at least four clutches per year (Bennett & Thakoordyal 2004), V. niloticus can produce at least two clutches per year (Faust, personal communication). Projects proposed 1. Explore possibility of creating a prototype farm for the sustainable production of Varanus lizards. Encourage and initiate a documented and verifiable captive breeding program for Varanus lizards in Ghana by exploring the possibility of creating a prototype farm for the sustainable production of Varanus lizards. Apply husbandry techniques developed for species of Varanus lizard that regularly reproduce in captivity to captive populations of V. exanthematicus and V. niloticus. To demonstrate the feasibility of affordable, sustainable farming of monitor lizards and establish basic husbandry techniques for keeping the animals in captivity and breeding insect prey. Farm and enclosure designs would be created in consultation with a team of experienced breeders of Varanus lizards. Proposed founder stock for farm are 20:30 V. exanthematicus and 10:20 V. niloticus. The farm would have to operate for at least 36 months to prove sustainability to CITES standards for captive bred sources. The major expense of farming Varanus is food. In nature V. niloticus is an opportunistic feeder, eating a wide variety of dead and living animal prey, whilst V. exanthematicus apparently specialises on living arthropods. Both species can consume large amounts of prey, with total predator prey mass ratios of around.1 for adults?) and up to.5 for juveniles (data from V. exanthematicus, probably lower in niloticus). On the assumption of 20% of body weight as food per week around 40kg of food per week would be required to maintain 50 adult V. exanthematicus and 30 V. niloticus. In captivity many Varanus lizards (but neither V. exanthematicus nor V. niloticus) reproduce consistently on diets of rodents and insects and some processed food. Obesity is very common among non reproductive captive individuals. The cost of feeding the animals and the importance of ensuring constant supplies of food mean that a self sufficient option is most desirable. Many suitable invertebrate prey can be farmed more efficiently than birds or mammals and the establishment of small scale invertebrate farms for orthopterans, roaches, snails and other invertebrates would be an essential prerequisite to a lizard farm. 2. Develop and evaluate methods for incubation of eggs, maintenance of adult animals in conditions conducive to reproduction and temporary housing of juvenile animals at high densities Optimal husbandry of animals reduces mortality before and after export. Wildlife dealers have to accommodate very large numbers of lizards over periods of weeks or months and suboptimal husbandry is highly detrimental to the quality of exports. Wildlife exporters in Ghana will be offered training and advice in consultation with experienced breeders of

4 Varanus lizards, and the opportunity to collaborate on experiments to evaluate permanent and temporary housing and egg incubation techniques. Husbandry of Varanus lizard underwent a quantum shift in the 1990s which resulted in large numbers of captive bred animals available in trade in Europe, North America and Australia, but has been adopted more slowly by institutions (Retes & Bennett 2001, Mendyk et al. 2014). Consequently most experienced Varanus breeders are private individuals, usually of amateur status. Exporters will be given the opportunity to learn about essential elements of Varanus husbandry and to participate in an attempt to find a suitable standardised enclosure that would be suitable for permanent maintenance of reproductive animals. Enclosures suitable for permanent housing of Varanus lizards within exporter s facilities could be designed and any created evaluated over at least 12 months. Holding of large numbers of hatchlings together prior to export often results in stress. Average number of V. exanthematicus in shipments from Ghana in was 390 lizards (+ 877, range 1-4,860). Hatchling monitor lizards have high surface area to volume ratios and are prone to both dessication and stress which increase mortality. Holding containers for mass exports should allow animals to hide and thermoregulate naturally whilst allowing ease of cleaning and access. Various designs for holding containers could be tested. Incubation of Varanus eggs is notoriously problematic, but recent advances in techniques have greatly increased success rates in many species. To evaluate suitable methods for exporters three methods will be tested using eggs obtained from females collected in December In total up to 300 eggs would be required. Rational for Exporters The aim is to develop methods to produce top quality Varanus offspring that can be verified as captive bred or sustainably ranched and maintain them prior to export in conditions that minimise mortality, dehydration and stress. Hatchling sized monitor lizards are preferred for wildlife trade. There is very little demand for adults and they are common at pet rescue centres in countries that import the juveniles. Earliest hatchlings become available around the beginning of March but eggs continue hatching through April and possibly May. The supply of hatchling sized animals is therefore limited to two or three months of the year. In good conditions V. exanthematicus grow very rapidly in the first year of life, and can attain sexual maturity within 9 months (Bennett & Thakoordyal 2004). Many imported V. exanthematicus die within the first year of life as a result of parasitic infestations thought to be acquired pre export (including nematodes, platyhelminthes,

5 protozoa) that stressed animals are particularly susceptible to. Consequently, captive bred or ranched animals from verifiable sources tend to be more valuable in trade than wild caught animals. Female monitor lizards do poorly in captivity and males are much more suitable pet animals. At present it is not possible to differentiate sexes of immature animals with certainty but techniques developed for other Varanus species might work on neonate West African monitor lizards. Ability to differentiate sex of hatchling would allow exporters to guarantee sex of the animals sold, or provide the option to return some females to the wild. Training and Education Many elements of the research proposed would make a suitable study for Msc or PhD candidates. If approval is given by Ghana Wildlife Division local researchers will be invited to collaborate on all aspects of the work. References Bennett, D. 2000a. Preliminary data on the diet of juvenile Varanus exanthematicus (Sauria: Varanidae) in the coastal plain of Ghana. Herpetological Journal. 10: Bennett, D. 2000b. The density and abundance of juvenile Varanus exanthematicus (Sauria: Varanidae) in the coastal plain of Ghana. Amphibia-Reptilia. 21: Bennett, D. 2000c. Observations on Bosc s monitor lizard (Varanus exanthematicus) in the wild. Bull. Chicago. Herp. Soc. 25 (8): Bennett, D. & Sweet, S.S Varanus exanthematicus. The IUCN Red List of Threatened Species 2010: e.t178346a Downloaded on 14 July Bennett, D. & R. Thakoordyal Savannah Monitor Lizards. The Truth about Varanus exanthematicus. Viper Press, Glossop. de Buffrenil, V Les Varans Africains (Varanus niloticus et Varanus exanthematicus) Donnees de synthese sur leur biologie et leur exploitation. CITES Secretariat, Geneva. 162pp. Cisse,M La Diapause chex les Varanides du Senegal. Notes. Africaines. No 131.IFAN Dakar:57-67.

6 Cisse,M L'Alimentaire des Varanides au Senegal. Bull.L'inst. Francais Afr. Noire. ser A. 39: Cisse,M Le cycle genital des Varans du Senegal. Bull L'institute Francais Afr. Noire (Sci.Nat.). 38: Cisse, M Varanus of the Sahel (Sudan). Phd thesis. University of Nice. Mendyk, R. W., L. Augustine & M. Baumer On the thermal husbandry of monitor lizards. Herpetological Review 45(4): Retes, F. & Bennett, D Multiple generations, multiple clutches, and early maturity in four species of monitor lizards (Varanidae) bred in captivity. Herpetological Review 32(4): Yeboah, S Aspects of biology of two sympatric species of monitor lizards Varanus niloticus and Varanus exanthematicus (Reptilia, Sauria) in Ghana. Afr.J.Ecol. 32:

7 Global trade in live Varanus exanthematicus Importer Declared Exporter declared Figure 1. Global trade in Varanus exanthematicus Table 1. Origin of CITES declared international trade in Varanus exanthematicus (Tanzania is outside the range of the species). Declared exports Proportion Ghana Benin Togo Mali Niger (Tanzania) Table 2. Source of V. exanthematicus in trade (*Ghana figures include animals that originate elsewhere) %Wild Caught %Captive Bred %Ranched Ghana* Togo Benin

University of Canberra. This thesis is available in print format from the University of Canberra Library.

University of Canberra. This thesis is available in print format from the University of Canberra Library. University of Canberra This thesis is available in print format from the University of Canberra Library. If you are the author of this thesis and wish to have the whole thesis loaded here, please contact