Plans to convert a derelict and abandoned 100 year old hospital into new homes could be delayed by the possible presence of bats.

The news comes after a planning application was made to Folkestone and Hythe District Council (FHDC) to demolish some of the redundant outbuildings and redevelop the Royal Victoria Hospital in Folkestone.

If planning permission is approved, the site, which closed in 2006, will be made into residential use.

But as previous reports from ecologists, made between 2007 and 2012, detected bats roosting at the site, a further study was undertaken this year by Batbox Ltd Surveys on behalf of the site developers Alliance Building Company.

The experts used powerful torches and binoculars to search the site, which included checking inside and out, in basements and in the roof voids.

They were searching for evidence of bats, include droppings, urine stains and 'rub' marks from the oil on the animals' fur.

And while the survey revealed there is 'no fresh evidence of bat use' in the hospital buildings a second, Phase 2, survey has still been recommended.

This is because inspectors found the buildings in such a dilapidated and vandalised state that a proper search could not be carried out.

A report from Batbox states: "The extremely hazardous condition of the hospital buildings precluded a thorough search of all areas, as consideration had to be given to the health and safety of the surveyors."

Additionally the inspection took place in February, which is when British bats remain in their hibernation period and therefore only a day time survey was carried out.

The report added: "It remains a possibility that bats are roosting in soffits or roofs of the former roost building and because bats and their roosts are protected by law, some further precautionary survey work should be undertaken.

"It is therefore recommended that a Phase 2 bat survey is carried out as early in bats' active season as possible to ascertain whether bats continue to roost in the buildings. Following that survey, further advice will be given."

Bats are protected by the Wildlife and Countryside Act 1981 because of their specific roosting requirements.

Disturbing the animal, or so much as obstructing a roost, is a criminal offence.

Therefore Natural England must be told of proposed action likely to disturb the animals or their roosts, and if evidence of bats is found a Natural England Bat Mitigation Licence is required.

Previous bat species spotted at the site in 2007 and 2012 include common pipistrelle and serotine bats.

It is not known when the second survey will be completed.

Redevelopment plans for the former hospital site - which opened in 1890 - include retaining and converting the main building, demolishing outer buildings and erecting new homes in other parts of the site.

It is hoped that work could start in the summer, depending on planning permission being granted.

During the bat survey, honey bees were sighted in one of the buildings at the Radnor Park Avenue site.

The report states: "What appeared to be a colony of honey bees was seen flying around an air vent at a high level."

A recommendation was made to seek the advice of bee experts.

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