Combat Injuries in Russian Tortoises (Testudo horsfieldii) - Sharon Chancellor MT, Darrell Senneke, and Chris Tabaka DVM
Copyright © 2003 World Chelonian Trust. All rights reserved
Related articles:
Differentiating Male and Female Testudo horsfieldii (Russian tortoise) - Chris Tabaka DVM
Russian Tortoises - Testudo (Agrionemys) horsfieldii Care - Darrell Senneke and Chris Tabaka DVM
ロシアントータス（ホルスフィールドリクガメ） - Testudo (Agrionemys) horsfieldii – ダレル セネーク、 クリス タバカ DVM
It is an oft cited observation that Testudo horsfieldii are very aggressive tortoises towards conspecifics1.. This behavior is often displayed by dominant tortoises viciously biting legs, the neck region, and around the eyes of the tortoises they wish to drive off. Male Russian tortoises will drive off other male tortoises during breeding season and if there is not enough room for the lesser male to escape, wounds such as the ones pictured in this article are very likely to occur. In the wild this does not pose a life threatening situation as the dominated combatant can escape prior to being severely damaged. In the literature density in the wild is given of up to 1800 specimens per square kilometer in prime habitat2. Prime habitat is defined as loamy soil with a high sand content and an abundant food source3. Upon reading this number the novice may think this species can be easily maintained in groups. It is very important to realize that at this density there are 555 square meters, or nearly 6000 square feet for each tortoise. While T. horsfieldii are gregarious in nature and known to share burrows with conspecifics4, the ability to escape aggressive behavior by other tortoises in the wild minimizes the severity of injuries sustained in these situations.
Unfortunately in captivity unless one is making use of a very large habitat, this can lead to very severe injuries as can be seen in the examples below. In addition, in captivity, this behavior is by no means restricted to adult males as it can be seen in adult females and hatchling behavior as well. If this type of behavior is observed the animals must be separated and maintained in separate locations until a larger habitat, preferably equipped with numerous sightline breaks is made available.
The following is an example of what can occur when two adult male Testudo horsfieldii are kept together. In this situation, the animals had been brought inside due to cool weather and were being kept together along with several adult and sub adult females. Once the animals warmed up, the smaller male immediately bit the larger one just above the eye at which point the injured animal was of course separated. While this injury will heal, one may not always be so fortunate.
Female tortoises can and often do receive injuries from the courting male. Males will drive a female into an area or position by biting the tail, legs, and head of the female he wishes to mate. Front limb scale loss and toenail loss are common injuries in captive groups of breeding T. horsfieldii. The damage can be very severe if breeding animals are kept in small spaces where a female cannot get away, or where there is only one breeding sized female. A minimum of one male per three females of similar size and sexual maturity is highly recommended so that no single female has to bear the brunt of the male’s aggressive breeding behavior. Once breeding season tapers off and the time for ovipositioning (egg laying) approaches, gravid females will drive off all other tortoises with the same aggressive biting as well as occasional mounting of the other tortoises. Gravid females can also cause serious injury.
Pictured below are some old injuries in adult female Russian tortoises. Both of these pictures were taken about a year after the injuries were incurred. In the photograph on the left, you can see a toenail that is growing back in. It was completely removed a year ago. In the picture on the right, the scar from an old scale removal injury is circled. Keep in mind these pictures were taken one year after the injuries, unfortunately no pictures were taken when they were “fresh”.
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| toenail lost in combat |
scale removal injury |
Hatchling Russian tortoises are small and considered adorable by their owners. Because of their size and vulnerability one would think that they would be very docile. However, this presumption does not hold true. Below are pictures of neck wounds that occurred during feeding time in a group of T. horsfieldii hatchlings. In this situation plenty of food was provided and spread about the small enclosure 60 X 90 cm (2 x 3 foot) so that all of the hatchlings could eat in peace. A number of sight barriers were also utilized (hide boxes, cage furnishings). As the owner watched, one hatchling stopped eating, stared at its intended victim of similar size, then approached and aggressively bit at its habitatmate's neck, tearing open the skin. It was all done in a matter of seconds stunning the owner of this once "adorable" creature.
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In the above situation there were seven hatchlings in all, after the injury was incurred they were then separated into two small groups of similarly sized hatchlings to give them all more space. A few days later a hatchling had a bloody eye and permanent damage that resulted in blindness to the injured eye (see picture below). The following season's group of hatchlings were kept in smaller groups of 2-3 individuals and again, one hatchling suffered an eye injury. Large enclosures with plenty of sight barriers for hatchlings are just as important as large enclosures for adults.
In captivity it is impossible to perfectly duplicate natural conditions. Animals that, in nature, may only occur at a density of a few per acre are forced into close proximity despite our best efforts at providing what may appear to us to be spacious habitats. It is vitally important that regular observation and examination be conducted to prevent such conflicts from getting out of hand. Hopefully the above pictures and information will help alert Russian tortoise owners as to the nature of the creatures they are keeping and thus prevent similar such injuries in their collections.
