Suncus etruscus is an insectivorous species, as are most other shrews. They eat ants and other small insects; in captive studies they have eaten mealworms and crickets. They don’t use their forefeet to aid in consuming food. So, the smaller the food, the easier it can be handled. When captive individuals are given large food pieces, they cannot eat them readily; small pieces need to be detached before they can be eaten. Etruscan shrews rely little on sight in locating food. Sometimes they may even run into their food. They are always looking for food in order to meet their high energy demands.
Animal Foods: insects
Primary Diet: carnivore (Insectivore )
Etruscan shrews are extremely small and therefore little is known about their predation. Owls are known predators. Owl pellets often contain the remains of Etruscan shrews.
Known Predators:
Suncus etruscus may be one of the smallest mammals living today, with most adults weighing between 1.8 and 3 grams and ranging from 35 to 50 mm in length. They tend to be grayish-brown with short soft hair, and they are often recognized by their small hind limbs. There is no apparent sexual dimorphism. The basal metabolic rate of these tiny creatures averages 3.22 cubic centimeters of oxygen per hour.
Range mass: 1.8 to 3 g.
Average mass: 2g g.
Range length: 35 to 50 mm.
Average basal metabolic rate: 3.22 cm3.O2/g/hr.
Sexual Dimorphism: sexes alike
Other Physical Features: endothermic ; bilateral symmetry
Average basal metabolic rate: 0.063 W.
There is little known about the life span of Suncus etruscus, but the lifespans of other species in the genus range from 1.5 to 3 years. Etruscan shrews are hard to keep alive in captivity due to their size and their large energy requirements.
Typical lifespan
Status: wild: 1.5 to 3 years.
Average lifespan
Status: captivity: 2.7 years.
The habitat of Etruscan shrews includes forest, shrub and grassland environments. Suncus hosei, a former subspecies of S. etruscus, has been found in the dipterocarp forests of Asia. Some older accounts report S. etruscus at elevations as high as 4250 meters and as low as 100 meters in Malaysia. However, due to the fact that some subspecies have been elevated to full species, this may not reflect the true elevational range of Suncus etruscus.
Range elevation: 630 to 1000 m.
Habitat Regions: temperate ; tropical
Terrestrial Biomes: savanna or grassland ; forest ; scrub forest
Etruscan shrews, Suncus etruscus, have a wide distribution, but they are mainly confined to the Mediterranean lowlands from Portugal to the Middle East. There are reports of S. etruscus in Africa. Many former subspecies that have since been elevated to species occur in Southeast Asia and Madagascar.
Biogeographic Regions: palearctic (Native ); oriental (Native ); ethiopian (Native )
Shrews are food for predators such as owls, and probably play a large role in controlling insect populations.
The importance of Suncus etruscus to humans in not known, aside from their importance as members of healthy ecosystems.
There are no known negative affects of Suncus etruscus on humans.
The conservation status on Suncus etruscus is of least concern. However, some of the former subspecies are threatened. Suncus fellowgordoni is endangered; Suncus hosei is vulnerable.
CITES: no special status
IUCN Red List of Threatened Species: least concern
Most shrews in the genus Suncus are solitary and territorial. In order to defend their territories, they all make some sort of chirping noises and show aggressive behavior toward any intruders. When Suncus etruscus is in torpor and then suddenly awakened it makes harsh shrieking calls and this noise is usually only made when it is unable to flee the area.
In a study using captive individuals, it was found that these shrews would make clicking sounds that would become more rapid the faster they were moving. When the animals were motionless the clicking sounds were not heard. It was believed that these sounds could be a form of echolocation; however, this behavior has only been observed in one study.
Shrews seem to rely most heavily on their senses of smell and touch to find food, as they have poor vision.
Communication Channels: acoustic
Perception Channels: visual ; tactile ; acoustic ; chemical
There are several former subspecies of S. etruscus that have been elevated to full species. These include Suncus madagascariensis, S. fellowsgordoni, S. hosei, and S. malayanus. There is little to no information on these species and some accounts still treat these as subspecies of S. etruscus. All of these species (or subspecies depending on the author) are extremely similar in size and appearance to S. etruscus.
The mating system of Suncus etruscus is not very well understood. In one study it was found that young pairs of S. etruscus did live peacefully during the mating season. It must be noted that the closely related species Suncus varilla appears to be monogamous, and pairs live together throughout the year. The small size and difficulty of capturing S. estruscus makes it difficult to study. It is not known if its behavioral characteristics are similar to those of S. varilla.
The time in which Suncus etruscus breeds and the information about its young have not been widely studied. However, other species in the genus Suncus have been known to breed at all times of the year, most notably Suncus murinus, which has been widely studied. Most pregnancies occur from October through December. One study of S. etruscus pairs found that the gestation of this species was about 27.5 days and that litter sizes were anywhere from 2 to 6. Weaning in the genus Suncus as a whole is from 17 to 20 days. Suncus varilla apparently reaches sexual maturity about 24 months after birth. Suncus murinus females, however, reach sexual maturity at around 36 days.
Breeding interval: Not known for this species
Breeding season: Not known for this species
Range number of offspring: 2 to 6.
Average gestation period: 27.5 days.
Key Reproductive Features: iteroparous ; gonochoric/gonochoristic/dioecious (sexes separate); sexual ; fertilization ; viviparous
Average birth mass: 0.19 g.
Average gestation period: 27 days.
Average number of offspring: 4.
Average age at sexual or reproductive maturity (male)
Sex: male: 365 days.
Average age at sexual or reproductive maturity (female)
Sex: female: 365 days.
All eutherian mammals nurture their young before birth via the placenta, and all mammals provide their newborns with milk. There is little else known about the parental investment of Etruscan shrews. Parental investment by other members of the genus Suncus is quite variable. In the case of Suncus murinus, both parents collect nesting material. Suncus murinus young have been seen caravanning behind their mother when they are learning to find their own food. Suncus varilla young stay with their mother for up to nine months after being weaned, whereas S. murinus young are separated from their parents within a few months.
Parental Investment: pre-fertilization (Provisioning, Protecting: Female); pre-hatching/birth (Provisioning: Female, Protecting: Female); pre-weaning/fledging (Provisioning: Female, Protecting: Female)
The Etruscan shrew (Suncus etruscus), also known as the Etruscan pygmy shrew or the white-toothed pygmy shrew, is the smallest known extant mammal by mass, weighing only about 1.8 g (0.063 oz) on average.[3][4][5][6][7] (The bumblebee bat is regarded as the smallest mammal by skull size and body length.[3][8])
The Etruscan shrew has a body length of about 4 cm (1.6 in) excluding the tail. It is characterized by very rapid movements and a fast metabolism, eating about 1.5–2 times its own body weight per day. It feeds on various small vertebrates and invertebrates, mostly insects, and can hunt individuals of the same size as itself. These shrews prefer warm and damp climates and are widely distributed in the belt between 10° and 30°N latitude stretching from Europe and North Africa up to Malaysia. They are also found in the Maltese islands, situated in the middle of the Mediterranean Sea.[2][5] Although widespread and not threatened overall, they are generally uncommon and are endangered in some countries.
The Etruscan shrew has a slender (not truncated) body, with a length between 3 and 5.2 cm (1.2 and 2.0 in) excluding the tail, which adds another 2.4 to 3.2 cm (0.94 to 1.26 in).[9] The body mass varies between 1.3 g (0.046 oz)[8] and 2.5 g (0.088 oz)[4][9] and is usually about 1.8 g (0.063 oz).[3] In comparison, the related greater white-toothed shrew can be twice as long and weighs four to five times more.[9] The head is relatively large, with a long, mobile proboscis, and the hind limbs are relatively small.[10] The ears are relatively large and protuberant.[9] The Etruscan shrew has a very fast heart beating rate, up to 1511 beats/min (25 beats/s) and a relatively large heart muscle mass, 1.2% of body weight.[3] The fur color on the back and sides is pale brown, but is light gray on the stomach. The fur becomes denser and thicker from fall through the winter.[9] The shrew usually has 30 teeth, but the 4th upper intermediate tooth is very small (rudimentary), and is absent in some individuals.[6] Near the mouth grow a dense array of short whiskers, which the shrew actively uses to search for prey, especially in the night.[7] Dimorphism in body features between males and females is absent.[10]
Etruscan shrews live alone except during mating periods. Their lifespan is estimated at typically around two years, but with a large uncertainty.[9][11] They protect their territories by making chirping noises and signs of aggressiveness.[12] They tend to groom themselves constantly when not eating, and are always moving when awake and not hiding. The hiding periods are short, and typically last less than half an hour. Clicking sounds are heard when these shrews are moving, which cease when they rest.[10] The shrews are more active during the night when they make long trips; during the day, they stay near the nest or in a hiding place.[6] They reach their maximum level of activity at dawn.[2]
Due to its small size and consequent high surface-area-to-volume ratio, the Etruscan shrew is at a constant risk of hypothermia, and would quickly freeze to death if not for its extremely rapid metabolism. Its skeletal muscles contract at a rate of about 13 contractions/sec during respiration alone. In cold seasons and during shortages of food, the shrews lower their body temperatures down to about 12 °C (54 °F) and enter a state of temporary hibernation to reduce energy consumption. Recovery from this state is accompanied by shivering at a frequency of 58 muscle contractions/sec.[3] This induces heating at a rate of up to 0.83 °C/min, which is among the highest values recorded in mammals; the heart rate increases exponentially with time from 100 to 800–1200 beats/min, and the respiratory rate rises linearly from 50 to 600–800 beats/min.[4]
Etruscan shrews mate primarily from March to October, though they can be pregnant at any time of the year. Pairs usually form in the spring and may tolerate each other and their young for some time at the nest. The gestation period is 27–28 days, and they have 2–6 cubs per litter.[2][9] Cubs are born naked and blind, weighing only 0.2 g (0.0071 oz). After their eyes open at 14 to 16 days old, they mature quickly. The mother usually moves the young when they are 9 to 10 days old, and if disturbed, she relocates them by leading them with her tail in a train-like formation, with each cub biting the tail of the one in front. The young Etruscan shrews are weaned at 20 days old. By three to four weeks of age, the young are independent and are soon sexually mature.[5][9][10]
The Etruscan shrew inhabits a belt extending between 10° and 40°N latitude across Eurasia.[3] In Southern Europe, it has been found in Albania, Bosnia and Herzegovina, Bulgaria, Croatia, Cyprus, France, North Macedonia, Malta, Montenegro, Greece, Italy, Portugal, Slovenia, Spain, and Turkey, with unconfirmed reports in Andorra, Gibraltar and Monaco; it has been introduced by humans to some European islands, such as Canary Islands.[2]
The shrew also occurs in North Africa (Algeria, Egypt, Libya, Morocco, Tunisia) and around the Arabian Peninsula (Bahrain, Israel, Jordan, Lebanon, Oman, Syria, and Yemen including Socotra). In Asia, it was observed in Afghanistan, Azerbaijan, Bhutan, China (Gengma County only), Burma, Georgia, India, Iran, Iraq, Kazakhstan, Laos, Malaysia (Malaysian part of Borneo island), Nepal, Pakistan, Philippines, Sri Lanka, Tajikistan, Thailand, Turkey, Turkmenistan and Vietnam. There are unconfirmed reports of the Etruscan shrew in West and East Africa (Guinea, Nigeria, Ethiopia) and in Armenia, Brunei, Indonesia, Kuwait and Uzbekistan.[1][5]
Overall the species is widespread and not threatened, but its density is generally lower than of the other shrews living in the area.[2] In some regions it is rare, especially in Azerbaijan, Georgia, Jordan and Kazakhstan (included into the Red Book).[5]
The Etruscan shrew favors warm and damp habitats covered with shrubs, which it uses to hide from predators. Areas where open terrain such as grasslands and scrub meet deciduous forests are usually inhabited.[9] It can be found at sea level but is usually confined to the foothills and lower belts of mountain ranges, though has been found up to 3,000 m (9,800 ft) above sea level.[9] It colonizes riparian thickets along the banks of lakes and rivers, as well as human-cultivated areas (abandoned gardens, orchards, vineyards, olive groves and edges of fields). The shrew, however, avoids intensively cultivated areas, as well as dense forests and sand dunes.[2] It is poorly adapted to digging burrows, so it arranges its nests in various natural shelters, crevices and others' uninhabited burrows.[5][6] They frequent rocks, boulders, stone walls and ruins, darting quickly in and out between them.[9]
Because of its high ratio of surface area to body volume, the Etruscan shrew has an extremely fast metabolism and must eat 1.5–2.0 times its body weight in food per day. It feeds mostly on various invertebrates, including insects, larvae and earthworms, as well as the young of amphibians, lizards and rodents, and can hunt prey of nearly the same body size as itself. It prefers species with a soft, thin exoskeleton, so it avoids ants when given a choice. Grasshoppers, where common, are often regular prey.[9] It kills large prey by a bite to the head and eats it immediately, but takes small insects back to its nest.[5][6][7] When hunting, it relies mostly on its sense of touch rather than vision, and may even run into its food at night.[10]
The largest threat to Etruscan shrews originates from human activities, particularly destruction of their nesting grounds and habitats as a result of farming. Etruscan shrews are also sensitive to weather changes, such as cold winters and dry periods.[5] Major predators are birds of prey.[6][10]
The Etruscan shrew (Suncus etruscus), also known as the Etruscan pygmy shrew or the white-toothed pygmy shrew, is the smallest known extant mammal by mass, weighing only about 1.8 g (0.063 oz) on average. (The bumblebee bat is regarded as the smallest mammal by skull size and body length.)
The Etruscan shrew has a body length of about 4 cm (1.6 in) excluding the tail. It is characterized by very rapid movements and a fast metabolism, eating about 1.5–2 times its own body weight per day. It feeds on various small vertebrates and invertebrates, mostly insects, and can hunt individuals of the same size as itself. These shrews prefer warm and damp climates and are widely distributed in the belt between 10° and 30°N latitude stretching from Europe and North Africa up to Malaysia. They are also found in the Maltese islands, situated in the middle of the Mediterranean Sea. Although widespread and not threatened overall, they are generally uncommon and are endangered in some countries.
