Meet the Eurasian water shrew, nature’s aquatic acrobat! It’s a master of underwater navigation, darting through streams and ponds with ease. Don’t be fooled by its small size—the water shrew has an insatiable appetite. Get ready to be amazed by this remarkable creature’s facts.
Phylum: Chordata
Class: Mammalia
Order: Eulipotyphla
Family: Soricidae
Genus: Neomys
1. They stand out from other species
Like other water shrews, the Eurasian water shrew features a long, pointed snout, teeth with red tips, as well as small eyes and ears. However, it distinguishes itself with its relatively larger size, weighing approximately 12 to 18g and measuring around 2.8 to 3.8 inches in length.
The species possesses a compact, plush coat that comes in shades of gray to black, boasting a velvety feel. Its underbelly is typically white. This coat is thick and waterproof, shielding it from chilly and damp environments. When the shrew dives, the outer hairs of this coat traps the air bubbles inside, helping the water shrew to float. However, the creature requires some form of anchoring if it wants to stay submerged for longer durations.
On their ears, there are white tufts of hair. You can also find stiff white hairs on the undersides of their large feet and long tail.
2. Eurasian water shrews are venomous
Water shrews predominantly hunt beneath the water’s surface, seeking out aquatic invertebrates such as caddisfly larvae, snails, shrimps, mollusks, water skaters, and crayfish. Additionally, they have been observed eating larger prey such as small fish, frogs, and amphibians like Pacific giant salamanders. These carnivores also include certain terrestrial insects, like dipteran larvae, in their diet.
Shrews have a constant need to eat throughout the day in order to prevent starvation, owing to their petite bodies and rapid metabolic rates.
These creatures possess exceptional hunting abilities, excelling in both terrestrial and aquatic environments. They exhibit remarkable speed while swimming and can submerge themselves up to a depth of 70cm, maintaining this position for 20 seconds.
Their navigation in water is facilitated by their fringed hind feet, which aid in propulsion, while their keeled tail functions as a rudder, allowing precise control over their movements. Their ears are sealed off by a pair of valves while underwater. After getting back to the land, they retreat into their burrows and take a brief moment to dry themselves off.
To hunt food, the shrews employ a poisonous secretion from their submaxillary gland to immobilize their prey. These species are one of the few mammals that have venom, just like the platypus.
Despite the iron content in their teeth, Eurasian water shrews, much like their shrew counterparts, are unable to break through the skin of larger creatures, including humans. This intriguing characteristic imparts a reddish hue to the tips of their teeth, thus earning them the moniker “Red-Toothed Shrew.” If a water shrew bites you, you will only get an irritable rash.
Water shrews encounter a variety of predators due to their ability to live in both land and water habitats. They are preyed on by weasels, fish, cats, otters, birds, and foxes.
3. Habitat
The Eurasian water shrew occupies a vast territory across Europe, spanning from the western regions of the UK to the eastern reaches of Mongolia. As a result, it can be found throughout this expansive area, encompassing Great Britain all the way to North Korea.
They live in various wetland environments, including moist grasslands, bogs, wet forests, rivers, sea shores, streams, lakes, marshes, and intertidal wetlands. It shows a preference for clean, swiftly moving water.
4. They live alone
The water shrew, a mammal known for its nocturnal habits, exhibits peak activity during the pre-dawn hours. It is a solitary creature, with both males and females maintaining their own territories, except during the breeding season when males venture into female territories for mating purposes.
These shrews can reside at a minimum distance of 2 miles from water, but it predominantly chooses to inhabit stream banks, where it engages in extensive burrowing. The entrances to its burrows can be found both above and below the water level, and the tunnels are narrow. This allows the shrews to squeeze out water from their fur. In terms of social behavior, these creatures don’t display a typical social hierarchy.
In the winter, they don’t hibernate but maintain their activities throughout the year.
5. Reproduction
The breeding season of Eurasian water shrews occurs throughout the warm season. The females can give birth to multiple litters per season. A typical litter comprises 3 to 8 offspring and can reach up to 12. However, the common litter size usually has about 5 – 6 young.
The females will go through a 24-day gestation period. The young nurse from their mother until they are 37 days old. They will reach sexual maturity at the age between 6 and 8 months. In the wild, these animals have a lifespan of about 3 years, but when kept in captivity, their lifespan is shorter, averaging around 1.6 years.
6. Threats and Conservation status
The Eurasian water shrew is classified as “Least concern” by the International IUCN Red List of Threatened Species. However, the population of these shrews has experienced a significant decline primarily due to habitat loss and degradation caused by pollution and drainage.
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