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Reproduction
Snakes produce offspring in 2 basic ways. The first involves development of the
fertilized eggs within the body of the female. When the embryos are fully developed, the offspring are born, appearing
like miniature adults. Boa constrictors, water and garter snakes, and rattlesnakes are live-bearing species and
are considered oviparous. The second
method involves deposition of oblong, leathery-shelled eggs within the environment, where the eggs incubate. At
the completion of embryonic development, the eggs hatch, producing miniature adults. Pythons and rat and milk snakes
are egg layers, and are considered
oviparous.
In either case, the newborn or newly hatched can fend for themselves and receive no parental nurturing. Many snake
species readily mate in captivity. One mating may result in up to 3 clutches of eggs or 3 "litters" of
live young. This is because sperm can be stored within the reproductive tract of the female after insemination.
The proper pairing of snakes according to age and sex is essential if reproduction in captivity is to be successful.
Sexing of snakes can be difficult because males generally resemble females. Male pythons and boa constrictors have
a spur on each side of the vent. Some females have spurs but they are usually smaller than those of males. These
observations can be misleading at times. Snakes under 18 inches long can usually be sexed by exerting pressure
on the tissues surrounding the vent Male snakes have paired hemipternal (elongated, spurred structures used during
copulation) that can be extruded with this maneuver. The widely accepted method for sexing most snakes over 18
inches in length requires specialized sexing probes. These elongated, blunt-tipped instruments are gently inserted
into the vent and directed toward the tail. The probe penetrates only a short distance in females and a much longer
distance in males. This procedure should only be attempted by experienced handlers.
Artificial Incubation of Snake Eggs
Artificial incubation of fertile snake eggs is quite easy. A small amount of water
is added to an empty Styrofoam picnic chest Then, a thick layer of peat moss, sphagnum moss, vermiculite, shredded
newspaper, or paper towels is added. The eggs are carefully introduced into this medium. Slightly moistening the
incubation material also helps prevent the eggs' drying out. Too much moisture, however, promotes formation of
mold, which will destroy the eggs' contents. The relative humidity required to incubate snake eggs falls within
the range of 75-85F. The covered Styrofoam chest is then placed on a heating pad, which is set on its lowest heat
setting. The ideal temperature range for most incubation lies between 78 and 84F. The average incubation period
for most snakes ranges between 55 and 60 days.
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