Hermann's tortoises communicate through a variety of visual, auditory, olfactory, and tactile signals. These signals are used in several different ways in reproduction. Females use vision to choose quality mates based on favorable morphological traits. Males also use high-pitched calls to attract females. If a female accepts the male's call, the male will be allowed to mount the female and mate. Before mating, Hermann's tortoises sniff for olfactory signals emitted by females, although it is not fully known what these olfactory signals represent.
Communication Channels: visual ; tactile ; acoustic ; chemical
Other Communication Modes: pheromones ; scent marks
Perception Channels: visual ; tactile ; acoustic ; chemical
Hermann's tortoises are listed as "Near threatened" on the IUCN red list. Populations have declined due to construction, poaching, wildfires, and herbicides. Construction results in drastic habitat loss and fragmentation. Road construction, especially, separates tortoise populations and leads to vehicular mortality. Wildfires have been reported to have eradicated up to 50% of the population. The effects of these disturbances have a large impact on Hermann's tortoise populations, due to their long lifespans and late age at sexual maturity. Reintroduction programs have been implemented in an attempt to stabilize existing populations.
US Federal List: no special status
CITES: no special status
State of Michigan List: no special status
For Hermann's tortoise eggs to be able to develop and hatch successfully, the temperature must stay in the range of 23 to 34°C, and mortalty rates are still quite high at the extreme ends of this range. Soil temperature directly determines the sex of the hatchling. When the temperature is between 31.5 and 33.5°C, more males than females are born (85 to 90% males at 33°C). However, this patterns follows a bell curve - at 31.5 and 34°C, the sex ratio is nearly 50:50. After hatching, the hatchlings are at a high risk of predation and stay close to their nests, only leaving their hatching sites after their carapace has completely developed and hardened.
Development - Life Cycle: temperature sex determination; indeterminate growth
There are no known adverse effects of Hermann's tortoises on humans.
Hermann's tortoises have entered the pet trade through European exports. Hermann's tortoises are also used for food in some Asian countries.
Positive Impacts: pet trade ; food
Hermann's tortoises prey on small mollusks and insects, and newly hatched young are preyed on by a number of different species. However, adult Hermann's tortoises are prey to very few natural predators. These tortoises are known to host nematode parasites.
Commensal/Parasitic Species:
Hermann's tortoises eat ground vegetation such as grasses, leaves and flowers. When vegetation is scarce, they may also eat small insects, snails, or slugs.
Animal Foods: insects; mollusks
Plant Foods: leaves; flowers
Primary Diet: herbivore (Folivore )
Hermann’s tortoises, are found along the northern coast of the Mediterranean Sea in western Europe, ranging from Romania and Greece to southern Spain. Up to a quarter of the total population is estimated to reside in the Italian peninsula.
Biogeographic Regions: palearctic (Native )
Hermann's tortoises prefer inland and coastal forest habitats. Females build their nests in the forests, which keeps the eggs isolated from predators. Due to habitat destruction within their range, they are also found in habitats such as dry, hilly grasslands or farmland. Despite being suboptimal, these habitats still allow for the tortoises to actively forage in ground vegetation.
Habitat Regions: temperate ; terrestrial
Terrestrial Biomes: savanna or grassland ; scrub forest
Other Habitat Features: suburban ; agricultural
The maximum lifespan of this species in either the wild or in captivity is not currently known. However, other species in the genus Testudo have been documented to live over 120 years in the wild.
Hermann's tortoises range in size from 120 to 230 mm total length and weigh 2 to 2.5 kg. Females tend to be larger than males and reach sexual maturity at a younger age. Hermann's tortoises are unique due to their divided supracaudal scute, which is a scale-like plate located on the tail end of their shell. Another unique feature of Hermann's tortoises is a horny scale located on the tail. The coloration of the shell varies - the western subspecies is very colorful, while the eastern subspecies is relatively dull. Both subspecies have distinct dark bands under the shell. These tortoises can have 4 or 5 front claws/digits, which is apparently strongly influenced by the genetic characteristics of the mother. Females with 4 claws on their front limbs are 4 times as likely to have offspring with the same number of claws. Sex can be identified in juveniles by the combination of a number of subtle differences in the shapes of the tail, carapace, plastron and anal scutes. It takes at least 4 years (ir sometimes up to 10) before carapace differences are obvious, as the carapace length must be 10 cm or more to be useful in sex determination.
Range mass: 2 to 2.5 kg.
Range length: 120 to 230 mm.
Other Physical Features: ectothermic ; heterothermic ; bilateral symmetry
Sexual Dimorphism: female larger; sexes shaped differently
Adult Hermann's tortoises have very few natural predators because of their ability to tuck into their shell to avoid predation. However, young Hermann's tortoises are at risk of predation by a number of species, including rats, birds (particularly magpies), snakes, wild boar, foxes, badgers, and hedgehogs. As a tortoise matures and its shell hardens, the risk of predation decreases.
Known Predators:
Anti-predator Adaptations: cryptic
Hermann's tortoises breed seasonally in February after their winter hibernation. Females use visual cues and high-ptched calls that are made by males to choose quality mates. It appears that olfactory cues are also used in mate selection, although their exact mechanism is still unknown. Males also compete to mate with females by biting the female's legs, but are not as aggressive as other species of tortoises. Females and males both have multiple mates.
Mating System: polygynandrous (promiscuous)
Hermann's tortoises begin mating immediately following hibernation, which ends in late February. Females build nests by digging into the ground, and then deposit their eggs several centimeters deep in the soil. Females may lay more than one clutch of eggs in one breeding season. Incubation lasts an average of 90 days, with the eggs hatching in mid-August to September. Under ideal temperature circumstances, up to 75% of eggs laid will be viable.
Breeding interval: Hermann's tortoises breed once yearly
Breeding season: Breeding occurs at the end of hibernation (late February), with nesting beginning in May and ending in July.
Average number of offspring: 3.
Range gestation period: 80 to 100 days.
Key Reproductive Features: iteroparous ; seasonal breeding ; gonochoric/gonochoristic/dioecious (sexes separate); sexual ; fertilization ; oviparous
There is no parental investment in this species once eggs have been laid. The only protection females give comes from placing her eggs in a nest that is underground. After laying their eggs, females leave them on their own. Hatchlings usually stay near the nest for the first few years of their lives to allow their carapace to completely develop.
Parental Investment: no parental involvement; female parental care ; pre-fertilization (Provisioning, Protecting: Female); pre-hatching/birth (Provisioning: Female, Protecting: Female)
