Bat vacation

Bat vacation

Thursday, October 10th, 2013

Wivenhoe House Hotel, on the University of Essex’s parkland campus, has recently been hosting guests of a different kind…

Wivenhoe House Hotel, on the University of Essex’s parkland campus, has recently been hosting guests of a different kind…

The transforming renovations of the Grade II listed hotel involved demolishing the 1980s extension and building a new wing on its footprint, enabling the first hotel school of its kind in the UK, The Edge Hotel School.

However, before demolition could take place, some unusual guests needed to be carefully moved out.

Three species of bats (common pipistrelle, soprano pipistrelle and brown long-eared bats) were enjoying life in their roosts at this choice location.

Some bat species are rare and endangered owing, mainly, to loss of roosting and foraging habitat, and all bats and their roosts are legally protected. Hence, when extensive works are required where bats are present, measures need to be taken to safeguard bats and to ensure that roosts are still available during and after the works.

A team of experienced staff from The Ecology Consultancy worked at the hotel site to ensure that the bats were able to move  into a newly adapted roost space as well as designing enhanced bat habitat within the site.

It started with a suite of bat surveys carried out at dusk and just before dawn to find out what bat species were present, how many there were, and what type of roost was on the site.Large numbers of bats usually indicate a maternity colony is present as females group together to raise their young and to teach them to fly.

Once we knew what bats were present, we adapted an existing nearby bat roost to be able to accommodate all the species present.

Just prior to demolition, the bats were excluded from the building by installing one way tunnels and plastic sleeves over roosting features and entry points to allow bats to exit but not enter the building. Two brown long-eared bats defiantly stayed put in the rafters for the first few days but, with patience and a methodical approach, they were all successfully excluded.

The exclusion was monitored to ensure that bats left and did not return. During these monitoring visits, bats were often seen flying to and from the nearby adapted roost. One morning, a common pipistrelle was seen trying to re-enter the building through the excluder, with no success, when a pipistrelle from the adjacent roost flew past.

The two bats circled around one another, flew off directly to the alternative roost, and tucked up inside! The clear communication and social attitude of the bats was fascinating to witness, as well as the acceptance of the new roost.

Once the bats had been excluded, the roof materials were removed by hand to ensure that any remaining bats would not be injured or killed during demolition. This was meticulous work as it was imperative that materials were carefully checked.

The new roost required on-going monitoring to measure its success and to see if any adjustments would be needed. We had seen the pipistrelles move in, but brown long-eared bats are typically more selective and can be less adaptable.

Our visits in 2012 confirmed that the brown long-eared bats have taken up residence in the new roost. It is  excellent that the mitigation has been successful and good to see that the roost has met the bats exacting requirements. But we’d expect nothing less than the most discerning of guests feeling right at home at such an auspicious hotel.  After all, if it’s good enough for Major-General Rebow, Constable, and the SAS, it’s surely good enough for our brown long-eared bats!

Richard Halsall, Deputy Director (Capital & Development) of the University’s Estate Management Section said “ I was delighted with the hard work, professional advice and practical solutions that The Ecology Consultancy completed, and which enabled us to open Wivenhoe House hotel on programme, without impacting on the strong environmental credentials of the development”.

Technical details:

A soprano and common pipistrelle roost was adapted to be suitable to support brown long-eared bats. Features were as follows:

– suitable dimensions for long-eared bats, which fly inside buildings prior to emerging at night to hunt.

– designed to be undisturbed by humans, but possible for ecologists to monitor annually.

– thermostatically heated to encourage use as a maternity colony

– roosting features including wedge boards and mortise joints were fitted

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