Jobs are being cut at the organisation which runs some of the county’s most important historical sites.

Sussex Archaeological Society, also known as Sussex Past, looks after some of of the best-loved buildings, landmarks and museums in Sussex.

The redundancies could mean the removal of qualified archaeologists from the society prompting fears that the care of sites including Lewes Castle, Anne of Cleves House in Lewes, Michleham Priory, and the Long Man of Wilmington could suffer.

The society is struggling to make ends meet and has made a loss of more than £700,000 during the past three years.

In a letter to members, chairman of trustees Peter Sangster said the society had suffered substantial financial losses in the past three years and predicted the worsening economic climate would reduce visitors numbers in 2009.

He said: “It is with great regret that I have to announce that the trustees have had to instigate a limited number of staff redundancies which will take effect early in 2009. Those members of staff affected are in the process of being individually notified.

“The trustees very much regret that this action has become necessary. However, these redundancies do not form a part of the longer term strategic plan to take the society forward over the next five years.”

The letter stated the society lost about £157,000 in 2006 and a further £186,000 in 2007. The loss for 2008 is estimated to be more than £400,000.

Visitor numbers were also down at attractions across the county and further difficulties were created by the drop in value of the society’s investment portfolio which no longer guaranteed such a good return.

Brigid Chapman, a member of Sussex Archaeology Society for the past 44 years, was critical of the redundancy plan.

She said: “We don’t want to lose academically qualified archaeologists from the society. Other longstanding members are also concerned about this.

“There surely must be some other way to save money rather than lose people. I’m sure members would rather pay extra than see this happen.”

The society, a registered charity, was founded in 1846.

It is the largest county society in the country.

Lewes MP Norman Baker said: “We are in a difficult financial situation and it is affecting all sectors of society wether it is Woolworths or civic societies such as this. It is a concern because the work it does in Lewes and around Sussex is very important.”