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Klerks, M. (2000). Adapting the namaqualand speckled padloper, homopus signatus signatus, to captive conditions. Turtle and Tortoise Newsletter, 6, 30–32.
Added by: Admin (17 Aug 2008 18:17:19 UTC) |
| Resource type: Journal Article BibTeX citation key: Klerks2000 View all bibliographic details  |
Categories: General Keywords: Chelonia, Cheloniidae, Haltung = husbandry, Homopus, Homopus areolatus, Homopus signatus, Malacochersus, Malacochersus tornieri, Schildkröten = turtles + tortoises, Testudinidae Creators: Klerks Collection: Turtle and Tortoise Newsletter |
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| Abstract |
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Testudinidae Homopus s. signatus is the world's smallest terrestrial tortoise (max. male, 87.5 mm carapace length, 96 g; female, 106 mm and 163 g) (Boycott, R.C. and Bourquin, O., 1988) and is endemic to Namaqualand, South Africa. The species is listed in Appendix II of CITES, but is not listed in the South African Red Data Book. In South Africa the species is also called "klipskilpadjie" which means little rock tortoise. This tortoise is found in a region with relatively low rainfall and can be found on rocky outcrops. In October 2001 two male and two female wild-caught Homopus signatus signatus (specimen studbook numbers 0035-0038) where imported from South Africa into the Netherlands (export permit EB2001/432, import permit 33145) to consolidate the studbook for this species within the Homopus Research Foundation. These specimens were from the same area (Springbok, Namaqualand) as previously imported specimens. After capture, during flight and customer transfer a data logger (HOBO temp, Onset computer corporation, Pocasset, USA) was placed in the transport box. While temperatures dropped briefly to less than 5oC during transport, these temperatures are also encountered in the wild at this time of year. Upon arrival, the animals were released into their new enclosures as quickly as possible. One pair (specimens 0035-0036) was placed at my location (Figure 1). Figure 1. Male Homopus exploring his new cage. Since the vast majority of wild specimens are found to carry nematodes (Loehr, 2002a), both animals were immediately treated with fenbendazole (Panacur, Hoechst, Frankfurt) at a dosage of 50 mg/kg body weight. The same dosage was repeated two weeks later. Their indoor enclosure measured 150 x 80 x 80 cm (l x w x h). Flat pieces of rock where positioned to create multiple crevices with soil on the bottom, mimicking natural hiding places (Loehr, 2002a). This is in contrast to another rockdwelling species, the pancake tortoise (Malacochersus tornieri), which prefers rock-rock crevices (Moll and Klemens, 1995). The enclosure was decorated with mopani wood and artificial succulents. The substrate was 8-10 cm deep and consisted of course gravel (diameter 2-3mm). An 80 W spotlight (Philips PAR Flood) and a 150 W halogen spotlight were placed in the enclosure 40 cm above the soil to achieve an initial temperature of approximately 25-30oC. and adjusted to mimic a southern photoperiod, but there were light influences through a blinded window in the room. Water was sprayed 3-4 times a week to stimulate feeding. Water was always present, but no drinking was observed. The front wall of the enclosure is only 18 cm tall. This design was chosen to better mimic natural conditions by allowing temperatures to decrease at night and to facilitate dehydration of the enclosure after spraying water. The enclosure was initially divided in two to separate the male and female. Upon arrival, the female weighed 176 g, the male 86 g. On November 6, 2001, the female produced one egg, weighing 12 g. The egg was deposited in a crevice and was not buried. General behavior Upon arrival both animals showed stress including standing in the corners of the enclosure, digging next to the cage divider, and ignoring food items. The female was less active than the male and spent more time in the retreats. This could have been related to the fact the female was gravid. After two weeks the separation was removed to allow the tortoises to interact and to provide more space, retreats and microclimates for each of them. The high activity level remained the same and the food was still refused, but the male stopped digging. The male and female also switched retreats. No aggression or mating activity was observed. Spraying of water to stimulate feeding resulted in increased activity. The high activity and non-feeding resulted in a rapid weight loss. Between October and late January, the male lost 12 g dropping to only 74 g; the female lost 15 g (though 12 g of this can be accounted for by the egg). Drinking, the syringe method After three weeks without observed feeding or drinking, I started offering them lukewarm tap water from a needleless syringe (Figure 2). I simply let the water drip down onto their nostrils and into their mouth. The first time I tried this with the female she drank over 20 ml of water within 10 minutes. She even pushed her nostrils to a rock where water from the syringe had dripped. This might reflect natural drinking behavior. Within 3 days the male also accepted water. Syringe water was provided daily but it was only accepted about twice a week. Figure 2. The male drinking from a syringe. Note the size in contrast to the author's hand. On advise of another studbook member, electrolyte was added to the water bowl, and irregularly to the water in the syringe (T. Licitra, pers. comm.). Also an estimated 5% Nutrilon Soya solution (milk formula for babies that contains soy protein, vegetable fat and is lactose free) was accepted without problems. Using the syringe to provide fluids had several advantages since it was not necessary to handle the animals and the scale on the syringe allowed estimation of the volume of water that the tortoises drank. A weight increase of 10-12 g after drinking was not unusual for either turtle. After starting to drink water, the animals appeared to stabilize and displayed calmer behavior. Feeding Various food items were offered, including dandelion, clover, endive, chicory, banana, grape, pear, Plantago, and tomato. Following Loehr (1999a) some flowers (Taraxacum officinale, Calendula officinalis and Trifolium repens) were also provided. However, both tortoises refused all food items. In an attempt to provoke feeding and to prevent further loss of weight, the animals were force-fed Nutrilon Soya with a needless syringe. If the animals did not cooperate instantly, they where placed back in the enclosure. Handling of the animals appeared to cause a lot of stress, especially the female, so I stopped force-feeding after only a few attempts. To stimulate their metabolism and to mimic natural temperature changes, the lights were moved closer to the substrate and the 80 W bulb was replaced with a 120 W bulb. On January 26, about two weeks after adjusting the temperature, some endive was eaten. At the same time, two succulent plants (Kalanchoe sp. and Crassula sp.) were placed in the enclosure. Selection of succulents should be done carefully to avoid plants treated with pesticides. Within a day they were feeding on the Kalanchoe sp. The succulents, about 15 cm tall, were completely eaten in a week. Within two days of the initial feeding they started accepting other greens like endive, chicory, alfalfa, and seedlings germinated from clover and katjang idjoe (taugé) seeds. With the exception of one Alöe dichotoma that was not eaten, no additional succulents were placed in the enclosure, but a sedum spp. is offered in the diet. The first feces were found a few days after they started eating. Discussion Survival rates of H. signatus in captivity have been reported to be low, due to its presumably highly specialized habitat and diet requirements (Barzyk, 1994). Yet, neither Boycott and Bourquin (1988) or Loehr (1999b) found them to require a specialized diet. Almost a year after my pair was imported, it is hard to imagine that they were ever difficult to feed. The food items that they initially refused are accepted now. Fruits like banana and pear were not included in the diet since I don't consider these appropriate for Padlopers. My results confirm that H. s. signatus can be adjusted to a captive diet, but that adaptation to captive conditions can be delicate and time consuming. Barzyk's conclusions (1994) may have been based on turtles that were collected commercially or illegally imported. In both cases there can be a long time-span between initial capture and release into stable captive conditions. Furthermore, there may be several housing locations before the tortoises arrive at their final destination. Considering the brief initial time-span during which the condition of my specimens rapidly became worse, it is easy to imagine the negative consequences of long time-spans between capture and release at the final captive location or housing at multiple locations (with different husbandry and climatic regimes) for short periods of time. Therefore I would recommend transferring specimens directly and without delay to new locations. Homopus. s. signatus lives in the Succulent Karoo biome and feeds partially on succulents (Loehr, 2002). It might be useful to include pesticide free succulents in the captive diet of Homopus signatus. With dehydrated tortoises it could be beneficial to prevent further dehydration. Captive hatchling H. s. signatus have been reported to be vulnerable for dehydration (Loehr, 1999a). For non-feeding animals, the succulents might be a trigger to start them feeding. Sufficient heat and lighting appear important for H. signatus to thrive under captive conditions. The increased light intensity and photoperiod might have contributed to the start of feeding. The syringe method worked well to provide fluids and was low stress since the specimens were not handled. This is in contrast to a widely used method like soaking. I assume this method might work for all Homopus species and even others tortoises. This method could also be of use for rehabilitation programs where Homopus may be encountered. There is a single observation of a wild H. signatus drinking from a shallow stream of water on a rock slab after rainfall (V. Loehr, pers. comm.). Literature Cited Palmer, M. 1994. The speckled tortoise, Homopus signatus, in captivity. Tortuga Gazette 30:1-5. Barzyk, J.E. 1994. Husbandry and captive breeding of the parrot-beaked tortoise (Homopus areolatus). Chelonian Conservation and Biology 1:138-141. Boycott, R.C. and Bourquin, O. 1988. The South African tortoise book, a guide to South African tortoises, terrapins and turtles. Johannesburg: Southern Book Publishers, 148 pp. Klemens, M.W. and Moll, D. 1995. An assessment of the effects of commercial exploitation on the pancake tortoise, Malacochersus tornieri, in Tanzania. Chelonian Conservation and Biology 1:197-206. Loehr, V.J.T. 1997. Homopus s. signatus, Namaqualand speckled padloper, captive breeding. African Herp News 26: 23-24. Loehr, V.J.T. 1999a. Dietary requirements of captive hatchling Namaqualand speckled padlopers (Homopus s. signatus). African Herp News 28:23-26. Loehr, V.J.T. 1999b. Husbandry, behavior and captive breeding of the Namaqualand speckled padloper (Homopus s. signatus). Chelonian Conservation and Biology 3(3): 468-473. Loehr, V.J.T. 2002a. Diet of the Namaqualand speckled padloper, Homopus signatus signatus, in early spring. African Journal of Herpetology. Loehr, V.J.T. 2002b. Male aggression in captive Namaqualand speckled padlopers (Homopus s. signatus). Bulletin of the Chicago Herpetological Society 37: 1.
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