Action

Breed reptiles in captivity: Snakes – Colubrids

How is the evidence assessed?
  • Effectiveness
    not assessed
  • Certainty
    not assessed
  • Harms
    not assessed

Study locations

Key messages

COMMUNITY RESPONSE (0 STUDIES)

POPULATION RESPONSE (18 STUDIES)

  • Reproductive success (18 studies): Seventeen studies in the USA, Costa Rica, the UK, Taiwan, Australia, India and unknown locations reported that 1–2 female colubrid snakes produced 1–12 clutches of 3–16 eggs. Ten of those studies reported hatching success of 67–100%, two reported hatching success of 25% and two reported that hatching success varied from 0–75%. Two of the studies reported that at least 18–20 eggs hatched successfully. One study also found that captive-bred offspring produced two clutches of 3–4 eggs and all hatched successfully. One study in the USA reported that three female San Francisco garter snakes produced broods of 9–35 young.
  • Survival (5 studies): Five studies in the USA and the UK found that 2–20 captive-bred snakes survived for at least 1–3 months and 2–3 years in captivity, and that from six broods of 9–35 captive-bred San Francisco garter snakes, six young died within four months of birth.

BEHAVIOUR (0 STUDIES)

About key messages

Key messages provide a descriptive index to studies we have found that test this intervention.

Studies are not directly comparable or of equal value. When making decisions based on this evidence, you should consider factors such as study size, study design, reported metrics and relevance of the study to your situation, rather than simply counting the number of studies that support a particular interpretation.

Supporting evidence from individual studies

  1. A study in 1968–1976 at Dallas Zoo and Fort Worth Zoo, USA (Tryon 1976) reported that wild-caught trans-pecos ratsnakes Elaphe subocularis and their captive-born offspring reproduced successfully in captivity. In 1973, a wild-caught female produced a clutch of six eggs following five years in captivity. Five of six eggs hatched successfully after an incubation period of 105 days. A female from this clutch produced a clutch of three eggs in 1975, and a clutch of four eggs in 1976. All seven eggs hatched successfully following incubation periods of 73–76 days. In 1968, an adult pair of snakes was acquired by Dallas Zoo. Two offspring from this pair were given to Fort Worth Zoo, where they were housed together in a 3-foot fibreglass cage with a pea gravel substrate, rocks and plastic plants. Eggs were removed and incubated in sealed 1 gallon jars in a medium of vermiculite and water (4 oz to one fluid oz water). Jars were opened at two-week intervals to replenish oxygen levels and temperatures were maintained at 28–32°C.

    Study and other actions tested
  2. A study in 1974–1976 at Fort Worth Zoological Park, USA (Tryon & Hulsey 1976) reported that Nelson's milksnakes Lampropeltis triangulum nelsoni bred successfully in captivity. One female produced one clutch/year for three years and a second female produced a single clutch. Clutch size ranged from 3–5 eggs, and 13 of 16 eggs hatched successfully. Two juveniles that were retained survived at least two years. A male and two females were acquired between 1964–1973 and bred successfully in 1974–1976. All three snakes were housed in a 2-foot fibreglass cage with a substrate of pea gravel. Temperatures fluctuated seasonally between 23–32°C. Groups of 2–3 eggs were transferred to sealed, gallon jars and incubated in vermiculite (1:1 ratio by weight with water). Incubation temperatures were maintained at 23–30°C.

    Study and other actions tested
  3. A study in 1973–1977 at Fort Worth Zoological Park, USA (Simmons 1977) reported that Chinese red snakes Dinodon rufozonatum bred successfully in captivity in two of four years. In 1973–1976, two females produced clutches of three and seven eggs. Two of three eggs from the first clutch and some from the second (number not provided) hatched successfully. Authors report an incubation period of 49 days. In 1977, a clutch of 12 eggs was produced, but these were still incubating at the time of writing. In 1973, a male and two female snakes were housed together in a 2-foot fibreglass cage, with a gravel substrate, rocks, plants and a water bowl. Temperatures ranged from 23–32°C. Gravid females were moved to a separate cage and provided a bowl containing damp vermiculite and/or moss. Eggs were placed in a 5-gallon aquarium in a 1:1 mixture of vermiculite and water, and incubated at 29–35°C.

    Study and other actions tested
  4. A study in 1974–1976 in a captive setting [location unknown] (Assetto 1978) reported that gray-banded kingsnakes Lampropeltis Mexicana alterna bred successfully in captivity. In 1976, a female produced a clutch of eight eggs, seven of which hatched successfully after an incubation period of around 70 days. The 8th egg was infertile. In 1974–1975, an adult pair of snakes was acquired. They were housed separately in 10 gallon tanks with a newspaper substrate, and temperatures were maintained at 24–28°C. In 1976, the female was introduced to the male on three consecutive days and was then moved to a 5.5 gallon aquarium half filled with damp potting soil. Eggs were removed and placed in a plastic box with vermiculite and water, and incubated at 28–32°C.

    Study and other actions tested
  5. A study in 1971 in the USA (Herman 1979) reported that scarlet kingsnakes Lampropeltis triangulum elapsoides bred successfully in captivity. One female produced a clutch of four eggs, and all four hatched successfully after an incubation period of around 66 days. In 1971, a pair of adult snakes was acquired and housed in separate 38 litre aquaria with paper towel substrates and pine bark. Temperatures ranged from 21–28°C. The male was transferred to the female’s aquaria for mating purposes. Eggs were incubated at 25–31°C between layers of damp paper towels in a 1 litre plastic container, sealed with clear plastic wrap. All snakes were released around two months after hatching.

    Study and other actions tested
  6. A study in 1979–1981 at Memphis Zoo and Aquarium, USA (Reichling 1982) reported that black pine snakes Pituophis melanoleucus lodingi bred successfully in captivity. In 1981, a single female produced seven eggs, and all seven hatched successfully. In 1979–1980, two female snakes and one male were obtained from Alabama and housed individually in 113 litre aquaria, with temperatures ranging from 25–32°C in summer and 9–18°C in winter. In March 1980 and April 1981, the first female was paired with the male, but no mating activity was observed. In April 1981, the second female was paired with the male and they mated successfully. Eggs were transferred to an 11 litre, sealed plastic box with small holes drilled in the sides and incubated in vermiculite (1:1 ratio by volume with water). Incubation temperatures were maintained at 24–31°C but dropped as low as 6°C at night.

    Study and other actions tested
  7. A study in 1981–1982 at Cheyenne Mountain Zoo, USA (Connors 1986) reported that a pair of Great Basin gopher snakes Pituophis melanoleucus deserticola bred successfully in captivity. In 1982, the female produced a clutch of seven eggs, and all seven hatched successfully after a 55–58-day incubation period. In 1981, a pair of snakes were acquired, and in 1982 they were placed together in an aquarium (73 x 31 x 28 cm) with a gravel substrate. A plastic container containing damp vermiculite was placed in the aquarium but was ignored by the female. Eggs were collected, wiped clean with zephiran chloride (1:750 solution) and covered with damp vermiculite in a stainless-steel container. They were incubated at 29.5°C.

    Study and other actions tested
  8. A study in 1982–1983 in San José Province, Costa Rica (Martinez & Cerdas 1986) reported that a pair of mussuranas Clelia clelia bred successfully in captivity. The female produced a clutch of 10 eggs, seven of which hatched successfully after 117–120 days of incubation. One egg did not develop, and two eggs contained fully developed but dead young with some physical deformities. In 1982, a pair of snakes were housed together in a wooden cage (122 x 62 x 60 cm). Temperature was 25°C and humidity was 60%. Eggs were incubated at 26–28°C in a fiberglass case (21 x 21 cm) on damp cotton. The case was kept inside a plastic bag and was opened daily for ventilation.

    Study and other actions tested
  9. A study in 1983–1986 at Dallas Zoo and Fort Worth Zoo, USA (Cover & Boyer 1988) reported that San Francisco garter snakes Thamnophis sirtalis tetrataenia bred successfully in captivity. In 1984–1986, three females produced six broods of 9–35 young/brood, following gestation periods of 79–98 days. Six young died or had to be put down within four months of birth. The male to female sex ratio of broods ranged from 19:16 to 5:12. Snakes were housed in plastic show boxes, 1 gallon glass jars or 5 gallon aquaria (36 x 22 x 26 cm) with a paper substrate and plastic hide boxes, bark and plastic leaves. Ambient temperatures were 27–30°C at Dallas Zoo and 21–32°C at Fort Worth Zoo, and spotlights provided basking spots at 32°C for gravid females.

    Study and other actions tested
  10. A study in 1986–1987 in the USA (Reichling 1988) reported that Louisiana pine snakes Pituophis melanoleucus ruthveni produced a single hatchling in captivity over two years. In 1986, a female produced a clutch of two infertile eggs. In 1987, the same female produced a clutch of four eggs, one of which hatched successfully and three of which did not develop. In 1986, a female and two male snakes were acquired and housed separately in 114 litre aquaria with a substrate of wood shavings. Temperatures ranged from 23–32°C. In March–May, snakes were introduced to each other for mating. Eggs were moved to an 11 litre plastic box containing moist vermiculite and incubated at 25–31°C. The boxes had small holes drilled in the sides and were opened for a few seconds every week.

    Study and other actions tested
  11. A study in 1989–1995 [location unknown] (Mamet & Kurdryavtsev 1997) reported that Mandarin rat snakes Elaphe mandarina bred successfully in captivity. In 1993–1995, a female produced three clutches (at least 5, 6 and 6 eggs/clutch), with 16 eggs hatching successfully. Incubation periods were around 48 days, and the ratio of males to females was 2:1. In 1989, a pair of snakes (recently captive-born) was acquired and housed together in a glass enclosure (40 x 25 x 25 cm). Temperatures were maintained at 22–26°C during the day and 16–18°C at night, and humidity was high. Snakes were then moved to separate enclosures (60 x 40 x 40 cm). The snakes reached maturity in 1992, and in 1993, the female was introduced to the male’s enclosure. Eggs were removed and incubated at 25–28°C in very high humidity on sphagnum moss Sphagnum sp..

    Study and other actions tested
  12. A study in 1993–1996 at the Riverbanks Zoo, South Carolina, USA (Foley 1998) reported that Oates’ twig snakes Thelotornis capensis oatesii bred successfully in captivity. A single female produced two clutches/year of 3–11 fertile eggs/clutch, and at least 20 eggs hatched successfully. Incubation periods ranged from 59–61 days (at 28.9°C) to 72–76 days (at 26.7°C). All hatchlings survived for at least three months. Authors also reported that in 1997, two captive bred females produced seven and five fertile eggs each at St. Louis Zoo, Missouri. In 1993–1994, one wild female and three wild males were acquired and subsequently paired up in a 122 x 107 x 81 cm tank, with basking spots between 29–35°C. Following mating, the female was moved to a smaller tank (61 x 41 x 31 cm). Eggs were incubated in vermiculite (2:1 ratio with water) in a 0.5 litre covered glass jar, and incubation temperatures ranged from 26.7–28.9°C.

    Study and other actions tested
  13. A study in 2007–2009 in a captive setting in Birmingham, UK (Radovanovic 2011) reported that a pair of red-tailed ratsnakes Gonyosoma oxycephala bred successfully during one of two years. In 2007–2008, a female produced four infertile eggs. In 2008–2009, the same female produced a clutch of four eggs, none of which hatched successfully (embryos died during development), and a clutch of four eggs, three of which hatched successfully. All three hatchlings survived for at least a month. In 2007, a pair of ratsnakes were acquired and housed in individual enclosures and only introduced to each other for mating. Ambient temperatures were 25–32°C during the day and 18–20°C at night. Eggs were removed and placed in a plastic container, partially buried in vermiculite (2:1 mix with water) and covered in damp sphagnum moss Sphagnum sp. and incubated at 30°C. The container was opened every two days.

    Study and other actions tested
  14. A study in 2010 in Missouri, USA (Penning & Cairns 2012) reported that red cornsnakes Pantherophis guttatus bred successfully in captivity. Two females produced at least 18 hatchlings. All captive offspring came from a single male and two female snakes. Eggs were moved to an incubator where the temperature was 28°C and the humidity was ≤80%.

    Study and other actions tested
  15. A study in 2011–2013 in Taiwan (Dieckmann et al. 2014) reported that a pair of Indo-Chinese rat snakes Ptyas korros reproduced successfully in captivity. In 2013, one female produced a clutch of six eggs, four of which hatched successfully. One egg was infertile, and one contained twin snakes that died before hatching. In 2011, a pair of rat snakes were brought into captivity. Eggs were placed in an incubator, where temperatures varied from 28°C during the day and 24°C at night.

    Study and other actions tested
  16. A study in 1984–1997 at Taronga Zoo, Sydney, Australia (McFadden & Boylan 2014) reported that brown tree snakes Boiga irregularis reproduced successfully after four years in captivity. In 1988–1995, a female produced seven clutches of 10–16 eggs. Authors report hatching data for three clutches, with nine of 12 (75%), zero of 11 (0%) and 13 (clutch size unknown) eggs hatching successfully. Reported incubation periods ranged from 82–92 days. Five of six eggs hatched successfully from an additional clutch that was laid soon after the snakes arrived in captivity, and authors reported that the female was most likely gravid when captured. A pair of snakes were acquired in 1984, and authors reported that incubation was attempted for four clutches of eggs. Details on incubation conditions were not reported.

    Study and other actions tested
  17. A study (year not provided) in a captive setting in Pilikula Biological Park, Karnataka, India (Lobo & Sreepada 2015) reported that montane trinket snakes Coelognathus helena monticollaris bred successfully in captivity. Two females laid one clutch each of eight and 12 eggs respectively, and 100% of eggs hatched successfully. Two pairs of adult montane trinket snakes were acquired and housed in one enclosure (2 x 2 m) with a soil and leaf litter substrate, along with some plants, deadwood, stones and a water pit. Temperatures were maintained at 22–28°C, and humidity was 80–90%. Eggs were removed and incubated in a plastic box with a soil substrate at 25–28°C and 80–90% humidity.

    Study and other actions tested
  18. A study in 2008 and 2013–2016 at London Zoo, UK (Kane et al. 2017) reported that two pairs of rhino rat snakes Gonyosoma boulengeri bred successfully in captivity. Two females laid one clutch each of nine eggs (including one infertile egg from one female). Three eggs from one of the clutches (33%) and six from the other (66%) hatched successfully. At least three of the hatchling snakes survived for at least three years. One pair of snakes was acquired in 2008, and a second pair in 2013. The 2013 pair was housed in an enclosure with a chipped bark substrate, a range of different plants and branches, and a hide box containing damp sphagnum moss Sphagnum sp. Ambient temperatures ranged from 24–28°C in summer and 18–26°C over winter, and a basking spot at 30–34°C was also provided. Eggs were removed and placed in vermiculite (1:1 mix with water by weight) and incubated at 28°C. Hatchlings were moved to individual plastic tanks.

    Study and other actions tested
Please cite as:

Sainsbury K.A., Morgan W.H., Watson M., Rotem G., Bouskila A., Smith R.K. & Sutherland W.J. (2021) Reptile Conservation: Global Evidence for the Effects of Interventions for reptiles. Conservation Evidence Series Synopsis. University of Cambridge, Cambridge, UK.

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Reptile Conservation

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Reptile Conservation
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