Water Vole — an Endangered Semi Aquatic Species Facing Survival Issues

Round-faced, short-tailed and often mistaken as simple rodent, water vole is a European mammal. This mammal loves to reside by the slow river banks, lakes or ponds and has many levels of habitats in the reservoirs. Known as Arvicola amphibious scientifically, these strong swimmers’ floor levels help prevent flooding. And, the sharp decrease in the number of water voles is also one of the reasons why Europe is facing intense situation of flood now and then.

According to one study, in 1990, UK had more than seven million water voles but by 1998 it reached to even less than million. And this pattern of decrease is now so consistent, that since 2008, it has become illegal to kill water voles intentionally. It would be indeed interesting to know that water voles daily eat 80% of their body weight and they survive by eating more than 150 different species of plant.

However, given that these species have declined significantly, water voles are protected in England under the Wildlife and Countryside Act 1981 (as amended) under Section 9. According to this law, it is a criminal offence to intentionally or recklessly disturb water voles whilst occupying a structure or place used for their habitat. Also, it is a criminal offence to intentionally kill, injure or take water voles. Therefore, when you are planning a new habitat or house, ecology consultancy services play an important role. Such service providers have schemes such as passive persuasion which includes using water vole exclusion fencing. This fencing encourages water voles to move to nearby alternative habitats or exclusion from the development area. However, in a situation, when there is no escape from ‘intentional’ damage, an ecology consultancy needs to have a Natural England license. This license allows the ecologist to trap and translocate the animals to an onsite or nearby receptor habitat. This option however is the last resort and faces stringent criteria.

Ecology and surveying of water vole

Also known as water rates, water voles have a blunt nose and are rat-sized. They mostly have black or brown fur and short rounded ears with a tail covered with hair. It is said that a water vole is about 140-220mm in length and has a tail 95-140mm. Its weight varies from 150-300g. They survive by eating grasses and other vegetation found on the waterside. They hardly have a five months life span. Though there are a few species that are found with a lifespan of 2 and half years.

According to ecological consultants water voles are found throughout Britain. They are available on a large range in the northern parts of Scotland and are absent in Ireland. They are mostly found on water sides. They occur on a large scale in vegetated banks and on the water regions like lakes and rivers. This is the reason why it is named as water rats. When discussed about these species it was said that water voles are more active during the day time than at night. A male water vole lives along 130 meters of water bank whereas females live along 70 meters.

Studies say that Water voles mostly have three - four debris a year. But this completely depends on the weather as the first among them can be born in the months of March or April. But under cold conditions the breeding can delay upto May and even June. They take birth under a nest in the ground. These nests are mostly made from grasses and rushes. When born these voles are found to be hairless and blind. But they have a quick growth and are said to be weaned in a period of 14 days.

Water voles are said to be harmless but it Britain they at times destabilize river banks. They are found to be quite different on continents.

Water vole survey and ecological engineering to save the species

Water Vole is a semi aquatic rodent found in Great Britain, Europe and Russia. In Britain, water voles live in burrows excavated within the banks of rivers, ditches, ponds, and streams. They survive up to 2 years and are protected species under UK legislation. As per Wildlife and Countryside Act 1981 (as amended) under Section 9 it is a criminal offense to intentionally kill, injure, take or sell the water vole and damage the places where they have shelter.

Before any development is commenced at riparian zone or areas it is prerequisite to do an environmental assessment to check the presence of the water voles and safeguarding the species from the proposed development. Water vole survey and mitigation can be helpful to meet the purpose.

Ecological consultants who are licensed from Natural England can undertake the Water vole survey. The period between mid April to mid September is the breeding duration when the water voles are more active and it is the best time to conduct water vole survey. As Water voles are shelter underground at the most, it is rare to have an actual sight to them, hence physical evidences are observed such as feeding areas, cutting patterns on vegetation (45 degree angle), burrows, ball nests, latrines, footprints and droppings.

If Water vole survey shows the presence of water voles at the development site, ecological consultants can give practical advice on mitigation techniques to be adopted to commence the development without hurting the species. It has been noticed that the most preferred technique used by ecologists is encouraging the water voles to shift from development area to new alternative habitat using water vole fencing. Depending on the site environmental conditions and development requirements, the water vole exclusion fencing systems are designed by licensed ecological consultants.

Using water vole survey and advanced ecological engineering, the reducing population of water voles can be controlled and saved from any development or amelioration.