Three inter-linked projects investigated aspects of water vole habitation.
> Habitat creation as a form of mitigation for water voles
> Impacts of landscape structure on water vole population genetics
> Re-establishing water voles
Water voles (Arvicola amphibious) have undergone one of the fastest documented declines of any British mammal during the last century. The main drivers of this decline are the loss and fragmentation of suitable wetland habitats and predation of populations by feral American mink (Neovison vison). The water vole is now protected under European law and a key priority for their conservation is to restore their geographical distribution by securing and enhancing connectivity between populations and by translocating or reintroducing individuals to augment bottlenecked or extirpated populations.
Researchers have been undertaking ecological and genetic research of both natural and reintroduced water vole populations in South East England to help inform on suitable conservation strategies that will help to secure the long term viability of populations.
Habitat creation as a form of mitigation for water voles
This project focused on the ecological and genetic monitoring of water voles following the largest managed coastal realignment scheme in England to evaluate the success of strategies designed to mitigate the impact of the scheme on water voles. The research forms part of the monitoring requirements of the ecological impact transition commissioned by the Environment Agency and managed by Jacobs U.K.
This study aimed to evaluate the success of different mitigation strategies implemented at the Medmerry Coastal Realignment in West Sussex and included:
>The colonisation rate and pattern of establishment of water voles into receptor habitat treated with different planting types.
>The success of passive displacement on water voles, using genetic monitoring and radio-telemetry.
>The impact of the scheme of genetic diversity and connectivity of populations.
Re-establishing water voles
This project focused on the monitoring the distributional changes, demography and genetic connectivity of water voles in the Arun Valley, West Sussex, following a reintroduction of water voles into Arundel Wetland Centre in 2005. A partnership project with the Sussex Wildlife Trust and the Heritage Lottery funded Arun and Rother Connections Project.
The aim of this study was to assess the colonisation rate, demographic stability and genetic connectivity of water voles in the Arun Valley to identify landscape features that influence demographic stability and dispersal rates.
Impacts of landscape structure on water vole population genetics
The main drivers in the decline of water voles described above are habitat loss, fragmentation and predation. However little is understood of the consequences of habitat loss, fragmentation and changes in landscape structure and use on water vole population genetics. One way of investigating population viability is to look at genetic variability within and between populations. One of the limitations in genetic studies is the cost and difficulty of obtaining sufficient samples. Many genetic studies have involved direct sampling from captured individuals. Recent successes in non-invasive sampling using hair tubes have shown potential for obtaining genetic samples remotely.
The project was a comprehensive study that combined genetic and demographic analyses to determine the conservation value of linear and non-linear wetlands for water voles and to establish the factors that have driven the current distribution of genetic variation across the south east of England.
It aimed to adapt and implement a remote non-invasive sampling method alongside a trapping study in various locations in the South East to investigate population demographics and genetic viability of water vole populations in the South East region and investigate the impacts of landscape structure and management on population dynamics.
The three primary aims to this study were:
> To determine whether the sociality, demography and genetic diversity of water vole populations were influenced by habitat linearisation.
> To identify genetically discrete clusters of populations and the contribution of landscape features, ecological processes and reintroductions to these, so that suitable management units and representative founder populations can be used to conserve regional genetic diversity and heritage.
> To establish the effectiveness of non-invasive hair capture tube devices for genetic studies on water vole populations.
Baker, R., King, P., Scott, D. & Southgate, F. (2009) Arun Valley Water Voles Report Summary: A study into the dispersal of water voles along the Arun Valley.
Baker, R. (2015) Demographic and genetic patterns of water voles in human modified landscapes: implications for conservation. PhD Thesis, University of Brighton.
Baker, R., Overall, A. & Scott, D. (2015) University of Brighton Commissioned Report: Water vole monitoring: Medmerry Coastal Realignment.
Baker, R. Overall, A. & Scott, D. (2015) University of Brighton Commissioned Report: Water vole molecular monitoring: Medmerry Coastal Realignment.
|Effective start/end date||1/01/05 → 31/12/15|