The egg shells are a similar density and appearance to a chicken egg, only smaller and more spherical. These full size eggs are then “shelled”, ready for laying. It is believed that tortoises can lay fertile eggs up to four years after mating, although fertility reduces significantly after each season.Īfter fertilisation the tiny eggs are segregated into clutches of two to twelve, depending on the species, then one clutch at a time are allowed to grow to full size. Tortoise gestation is in fact quite remarkable with regards to the time scales involved, because the female can vary the length of the gestation period (from fertilisation to laying) depending on the environmental and nesting conditions. One single mating results in up to 30 eggs being fertilised, although these will not be laid together in one clutch. The male usually mates with a female several times before finally letting her to go free. This is the only time that one will ever hear vocalised sounds made by a tortoise (except for the occasional discontented “hiss”) Each individual species generates a sound which is unique to their own kind. Ejaculation is followed shortly after, simultaneously accompanied by high pitched “squeaking” from the male. This pushes through his ventral opening of the cloaca and enters hers. The male then erects his penis (known as a hemi-penis). After adjusting his positioning, the male shuffles and wiggles his cloaca (tail), until his ventral opening lines up with the females opening. This allows the curvature of the females humped carapace to sit nicely underneath him. Once the male has mounted the female, it succeeds in keeping the stance by a combination of balancing on his rear legs and by possessing a more concave plastron than the female. Male tortoises when defending a territory from another male will resort to this courtship behaviour, even including mounting, but in this situation the ramming and biting is effectively used to dominate and ward off the offending male. This is the cue for the male to mount her. Eventually the female after enduring bites on all of her limbs, will stop attempting to escape and retract into her shell. The type of aggressive behaviour demonstrated by these amorous males varies between differing species, from biting and head bobbing rituals of the Testudo Horsfieldii, to considerable and often wound inflicting biting and shell battering from Testudo Ibera. Unlike other parts of the animal kingdom where partners are affectionately wooed by attractive and colourful displays, female tortoises are bullied into submission though relentless ramming, biting and butting from their male counterparts. Then courtship begins.Ĭourtship techniques vary from species to species, but the common denominating factor between the entire Mediterranean groups is aggression. The mating process begins with the male tortoise picking up on a female’s scent trail and following it until he ultimately reaches his target. In some parts of the Mediterranean coastline, tortoises can often be found mating at chance intervals throughout the year. This is somewhat dependant on the tortoise’s geographical location. Tortoises in the wild usually have stronger mating urges during the spring, after hibernation, though until mid-summer. In certain other cases, female tortoises suddenly became very ill or died during gestation or attempted egg laying efforts. Some eggs seemed to hatch with very little persuasion, while others inevitably went rotten, collapsed or exploded in the incubator. In fact many enthusiast level keepers had very variable results. However, captive breeding success has only quite recently been fully understood. One of the most rewarding and enjoyable aspects of tortoise keeping happens when your charges have offspring.
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