Testudo hermanniHermann’s Tortoise

Geographic Range

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. (Longepierre, et al., 2001; Mazzotti, 2004)

Habitat

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. (Burke, et al., 1989; Mazzotti, 2004; Rugiero and Luiselli, 2006)

Physical Description

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. (Burke, et al., 1989; Eendebak, 2001; Galeotti, et al., 2007; Girling, 2002; Mafli, et al., 2011)

  • Sexual Dimorphism
  • female larger
  • sexes shaped differently
  • Range mass
    2 to 2.5 kg
    4.41 to 5.51 lb
  • Range length
    120 to 230 mm
    4.72 to 9.06 in

Development

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. (Bartlett, et al., 2006; Bonin, et al., 2006; Eendebak, 2001)

Reproduction

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. (Bonin, et al., 2006; Galeotti, et al., 2005; Galeotti, et al., 2007; Palika, 2006)

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. (Bartlett, et al., 2006; Bonin, et al., 2006; Eendebak, 2001)

  • 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

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. (Bartlett, et al., 2006; Palika, 2006)

  • Parental Investment
  • no parental involvement
  • female parental care
  • pre-fertilization
    • provisioning
    • protecting
      • female
  • pre-hatching/birth
    • provisioning
      • female
    • protecting
      • female

Lifespan/Longevity

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. (de Magalhaes and Costa, 2009)

Behavior

Hermann's tortoises hibernate during the winter and become active again in late February. These tortoises are active during the day, and may aestivate in summer months, if necessary. (Bartlett, et al., 2006; Bonin, et al., 2006; Palika, 2006)

  • Range territory size
    7000 to 74000 m^2

Home Range

The home range of Hermann's tortoises varies from population to population. Females usually have a larger home range, stretching from 0.9 to 7.4 ha. Males have a home range from 0.7 to 4.6 ha. These home range sizes may be limited by habitat loss. (Mazzotti, et al., 2002)

Communication and Perception

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. (Galeotti, et al., 2005; Galeotti, et al., 2007)

Food Habits

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. (Bartlett, et al., 2006; Del Vecchio, et al., 2011)

  • Animal Foods
  • insects
  • mollusks
  • Plant Foods
  • leaves
  • flowers

Predation

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. (Bonin, et al., 2006; Palika, 2006)

  • Anti-predator Adaptations
  • cryptic

Ecosystem Roles

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. (Bartlett, et al., 2006; Del Vecchio, et al., 2011; Martinez-Silvestre, 2011; Neiffer, et al., 2005)

Commensal/Parasitic Species
  • Tachygonetria conica (Family Oxyuridae, Phylum Nematoda)

Economic Importance for Humans: Positive

Hermann's tortoises have entered the pet trade through European exports. Hermann's tortoises are also used for food in some Asian countries. (Jacobson, 1994)

Economic Importance for Humans: Negative

There are no known adverse effects of Hermann's tortoises on humans.

Conservation Status

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. (Bertolero, et al., 2007; Guyot and Clobert, 1997; Rugiero and Luiselli, 2006; Willemsen and Hailey, 2001)

Contributors

Lindsey Lavender (author), Radford University, Karen Powers (editor), Radford University, Kiersten Newtoff (editor), Radford University, Melissa Whistleman (editor), Radford University, Jeremy Wright (editor), University of Michigan-Ann Arbor.

Glossary

Palearctic

living in the northern part of the Old World. In otherwords, Europe and Asia and northern Africa.

World Map

acoustic

uses sound to communicate

agricultural

living in landscapes dominated by human agriculture.

bilateral symmetry

having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends. Synapomorphy of the Bilateria.

chemical

uses smells or other chemicals to communicate

cryptic

having markings, coloration, shapes, or other features that cause an animal to be camouflaged in its natural environment; being difficult to see or otherwise detect.

diurnal
  1. active during the day, 2. lasting for one day.
ectothermic

animals which must use heat acquired from the environment and behavioral adaptations to regulate body temperature

female parental care

parental care is carried out by females

fertilization

union of egg and spermatozoan

folivore

an animal that mainly eats leaves.

food

A substance that provides both nutrients and energy to a living thing.

herbivore

An animal that eats mainly plants or parts of plants.

heterothermic

having a body temperature that fluctuates with that of the immediate environment; having no mechanism or a poorly developed mechanism for regulating internal body temperature.

hibernation

the state that some animals enter during winter in which normal physiological processes are significantly reduced, thus lowering the animal's energy requirements. The act or condition of passing winter in a torpid or resting state, typically involving the abandonment of homoiothermy in mammals.

indeterminate growth

Animals with indeterminate growth continue to grow throughout their lives.

iteroparous

offspring are produced in more than one group (litters, clutches, etc.) and across multiple seasons (or other periods hospitable to reproduction). Iteroparous animals must, by definition, survive over multiple seasons (or periodic condition changes).

motile

having the capacity to move from one place to another.

native range

the area in which the animal is naturally found, the region in which it is endemic.

oviparous

reproduction in which eggs are released by the female; development of offspring occurs outside the mother's body.

pet trade

the business of buying and selling animals for people to keep in their homes as pets.

pheromones

chemicals released into air or water that are detected by and responded to by other animals of the same species

polygynandrous

the kind of polygamy in which a female pairs with several males, each of which also pairs with several different females.

scent marks

communicates by producing scents from special gland(s) and placing them on a surface whether others can smell or taste them

scrub forest

scrub forests develop in areas that experience dry seasons.

seasonal breeding

breeding is confined to a particular season

sexual

reproduction that includes combining the genetic contribution of two individuals, a male and a female

suburban

living in residential areas on the outskirts of large cities or towns.

tactile

uses touch to communicate

temperate

that region of the Earth between 23.5 degrees North and 60 degrees North (between the Tropic of Cancer and the Arctic Circle) and between 23.5 degrees South and 60 degrees South (between the Tropic of Capricorn and the Antarctic Circle).

terrestrial

Living on the ground.

tropical savanna and grassland

A terrestrial biome. Savannas are grasslands with scattered individual trees that do not form a closed canopy. Extensive savannas are found in parts of subtropical and tropical Africa and South America, and in Australia.

savanna

A grassland with scattered trees or scattered clumps of trees, a type of community intermediate between grassland and forest. See also Tropical savanna and grassland biome.

temperate grassland

A terrestrial biome found in temperate latitudes (>23.5° N or S latitude). Vegetation is made up mostly of grasses, the height and species diversity of which depend largely on the amount of moisture available. Fire and grazing are important in the long-term maintenance of grasslands.

visual

uses sight to communicate

References

Bartlett, R., P. Bartlett, M. Earle-Bridges. 2006. Turtles and Tortoises. Hauppauge, NY: Barron's Educational Series, Inc..

Bertolero, A., D. Oro, A. Besnard. 2007. Assessing the efficacy of reintroduction programmes by modelling adult survival: The example of Hermann's tortoise. Animal Conservation, 10/3: 360-368.

Bonin, F., B. Devaux, A. Dupre. 2006. Turtles of the World. Baltimore, MD: The Johns Hopkins University Press.

Burke, R., IUCN/SSC Tortoise and Freshwater Turtle Specialist Group, P. Harpel-Burke. 1989. The Conservation Biology of Tortoises. Gland, Switzerland: IUCN.

Del Vecchio, S., R. Burke, L. Rugiero, M. Capula, L. Luiselli. 2011. Seasonal changes in the diet of Testudo hermanni hermanni in central Italy. Herpetologica, 67/3: 236-249.

Eendebak, B. 2001. Incubation period and sex ratio of Testudo hermanni boettgeri. International Congress on Testudo Genus: 1-14. Accessed April 24, 2012 at http://www.schildpadden.akkido.com/docs/pub2.pdf.

Galeotti, P., R. Sacchi, M. Fasola, D. Rosa, M. Marchesi, D. Ballasina. 2005. Courtship displays and mounting calls are honest, condition-dependent signals that influence mounting success in Hermann's tortoises. Canadian Journal of Zoology, 83/10: 1306-1313.

Galeotti, P., R. Sacchi, D. Rosa, M. Fasola. 2007. Olfactory discrimination of species, sex, and sexual maturity by the Hermann's Tortoise Testudo Hermanni. Copeia, 2007/4: 980-985.

Girling, S. 2002. Pet Owner's Guide to the Tortoise. Dorking, Surrey: Ringpress Books.

Guyot, G., J. Clobert. 1997. Conservation measures for a population of Hermann's tortoise Testudo hermanni in southern France bisected by a major highway. Biological Conservation, 79/2-3: 251-256.

Jacobson, E. 1994. Causes of mortality and diseases in tortoises: A review. Journal of Zoo and Wildlife Medicine, 25/1: 2-17.

Longepierre, S., A. Hailey, C. Grenot. 2001. Home range area in the tortoise Testudo hermanni in relation to habitat complexity: implications for conservation of biodiversity. Biodiversity and Conservation, 10: 1131-1140.

Mafli, A., K. Wakamatsu, A. Roulin. 2011. Melanin-based coloration predicts aggressiveness and boldness in captive eastern Hermann's tortoises. Animal Behaviour, 81/4: 859-863.

Martinez-Silvestre, A. 2011. Massive Tachygonetria (Oxyuridae) infection in Herman's tortoise (Testudo hermanni). Consulta, none: 409-412. Accessed April 24, 2012 at http://www.amasquefa.com/uploads/105624.pdf.

Mazzotti, S. 2004. Hermann's tortoise (Testudo hermanni): Current distribution in Italy and ecological data on a population from the north Adriatic coast (Reptilia, Testudinidae). Italian Journal of Zoology, 71/1: 97-102.

Mazzotti, S., A. Pisapia, M. Fasola. 2002. Activity and home range of Testudo hermanni in northern Italy. Amphibia-Reptilia, 23/3: 305-312.

Neiffer, D., D. Lydick, K. Burks, D. Doherty. 2005. Hematologic and plasma biochemical changes associated with Fenbendazole administaration in Hermann's tortoises (Testudo hermanni). Journal of Zoo and Wildlife Medicine, 36/4: 661-672.

Palika, L. 2006. Turtles and Tortoises for Dummies. Hoboken, NJ: Wiley Publishing, Inc..

Rugiero, L., L. Luiselli. 2006. Ecological modelling of habitat use and the annual activity patterns in an urban population of the tortoise, Testudo hermanni. Italian Journal of Zoology, 73/3: 219-225.

Willemsen, R., A. Hailey. 2001. Effects of spraying the herbicides 2,4-D and 2,4,5-T on a population of the tortoise Testudo hermanni in southern Greece. Environment Pollution, 113/1: 71-78.

de Magalhaes, J., J. Costa. 2009. A database of vertebrate longevity records and their relation to other life-history traits.. Journal of Evolutionary Biology, 22/8: 1770-1774.