BREEDING COLUBRIDS
Elaphe, Pituophis and Lampropeltis sp.
INTRODUCTION
First period: for a 4 month period (i.e. from August to December) females need to gain weight prior to the cooling period. Food is offered weekly. An adult Corn Snake may eat 8-12 mice per months during this period and males generally will need less food than the females. Weights should be monitores and fasting of males during the mating season.
Temperatures should be maintained between 24-28ºC to enable digestion. Females store fat in the caudal body which will later be used during egg production.
Second period: for the following 3 months there is a temperature decrease to initiate vitello-genesis and spermatogenesis. Temperatures are typically kept at 13-18ºC. Males and females are kept separately and no food is offered during this period, only water.
Although temperature is a factor and is considered a trigger of the breeding season, photoperiod should also be considered as a contributing factor, although more studies are needed. These snakes have managed to breed with photoperiods between 13-24h of light without convincing results. A general guideline would be to maintain 12h of light and reduce to 8h during brumation or the cooling period.
Third period: Temperature is increased to 28ºC and feeding starts. Temperature may be reduced to 22-24ºC at night. Ideally a temperature gradient should be offered.
Approximately 20-30 days after temperature increase (around the end of March) they will shed.
During the next couple of weeks the females will reach their maximum vitellogenic development. The best way to tell if a female is ready to mate is to introduce a male. If the female starts abrupt tail movements and stays away then she probably is not ready. The male will either try to overcome the female or will lose interest and they should be separated. If the female initiates slow moves and allows the male to reach on top of her whilst she exposes the cloacal region then she is ready. If there is a effective mating they should be separated and the male introduced a further 2 times 2-3 days apart. Once she is gravid she shall start to reject the male.
Females continue to feed for a few more weeks and then will go off food 3 weeks before oviposition. Egg development and gestation period lasts 28-45 days. She will shed 7-14 days prior to egg laying which generally occurs in May (this may happen later on in the year).
Females will shed prior to egg laying. From the moment this happens it is very important to offer an adequate egg laying area which may contain a soil and moss substrate. If this is a large tub a hole can be made in the lid or top and substrate depth around 7-8cm. Days prior to egg laying females will increase their activity levels and seem slightly nervous or anxious. Care should be taken that the eggs are not laid in the water bowl - this may be removed from the enclosure as long as oviposition is near.
Fourth period: this period counts from the moment the female starts to feed again. Mating may also take place during this period as long as the females body condition is adequate and new follicles will be formed.
INCUBATION AND HATCHING
The eggs are laid containing a substance that hardens and keeps them together after approximately 30minutes. fertile eggs typically are firm and white, whereas infertile eggs are often dull and possibly softer. Often an infertile clutch is laid earlier than expected.
An adequate incubation substrate is a mix of vermiculite and water at a 3/4 ratio placed in a plastic tub with a depth of 7-8cm. Eggs are normally positioned buried 1/2 or 3/4 in the substrate. Small holes may be made in the sides of the tub for ventilation.
Una profundidad de 5-7 cm de vermiculita en el recipiente de incubación que llevará unos pequeños agujeros de unos 3mm de diámetro disponiendo los huevos en la parte opuesta a la zona de ventilación. Si prescindiésemos de esta zona podrían morir por hipoxia los embriones. Los huevos serán enterrados dejando expuesto 1/3 ó 1/2 de su superficie. The tub and the eggs can be weighed weekly and water added to reach the initial weight - very litte water is necessary normally but will depend on the ventilation holes and the incubator relative humidity outside the tub.
Temperatures should be a constant 23.5-27.5ºC, avoiding temperatures over 30.5ºC. With slightly lower temperatures the incubation period time will increase. Hatching normally takes between 12-48h from when the first crack appears.
Average hatching times in commonly kept species:
Lampropeltis getulus y L.triangulum 60-15 days
Lampropeltis mexicana 55-65 days
Elaphe guttata y E.obsoleta 55-65 days
Pituophis melanoleucus ssp. 68-75 days
A few days would be added for each 0.5ºC decrease under 26.6ºC.
GROWTH TO ADULT SIZE
It was previously thought that King and Milk snakes (Lampropeltis sp.) should reach 3-4 years old before reaching sexual maturity. Recent studies show that in the reproductive capacity depends on size and not on age. it has been proven that males at just 9 months of age and females at 18 months can produce offspring. It has also been proven that reduced feeding increases reproductive maturity and some snakes never become sexually mature at all.
A general feeding regime for hatchlings may be pinkie mice every 2 days up to an age of 5-6 months (feeding is interrupted during shedding) and every 4-7 days thereafter. Shedding generally occurs every 21-30 days.
SPECIES SPECIFIC FEEDING
Rats and mice are generally used, although chicks are another option.
Pituophis melanoleucus, Elaphe guttata and E.obsoleta: Increase rodent size at earlier ages up to the size of a rat as adults. A moist substrate and/or moss is generally used for the first 8-10 months and then a drier environment thereafter.
Lamproppeltis getulus and L.calligaster: Prey size is increased proportionately with snake size and they are kept on s a dry substrate from early age up to adults.
Lampropeltis triangulum ssp.: Prey size is increased proportionately. A moist substrate and/or moss is generally used for the first 8-10 months and then a drier environment thereafter.
Lampropeltis mexicana, L.pyromelana, L.zonata and L.triangulum: in their natural environment these hatchling will often feed on small lizards and although small rodents are offered these may be slow starters. If they are poor feeders, scenting the mice may be performed or feeding with or small lizards. A moist substrate and/or moss is generally used for the first 8-10 months and then a drier environment thereafter.