The National Trust has confirmed there will be 72 redundancies among its staff in Northern Ireland, saying the cuts are "unavoidable" due to the pandemic.
The organisation as a whole is cutting almost 1,300 jobs across the UK as part of a plan to save about £100m a year.
The National Trust's Director for Northern Ireland, Heather McLachlan, said that of the 72 local redundancies, 51 are voluntary and 21 are compulsory.
She said it was a "very sad day" and paid tribute to staff who are leaving.
"This is an unavoidable outcome of the exceptionally challenging times all charities, businesses and wider society are facing due to the pandemic," Ms McLachlan said.
Non-essential businesses and leisure facilities across Northern Ireland were ordered to close in late March as the first wave of coronavirus took hold.
National Trust parks and gardens reopened to the public on 3 June, but new safety measures had to be introduced in its properties to prevent the spread of infection.
This included a requirement for visitors to book in advance in order to guarantee admission to some sites.
The National Trust has a total workforce in Northern Ireland of 570, which means it is losing almost 13% of its employees.
At this stage, the organisation could not yet say how many of the Northern Ireland workers affected by redundancy are full-time staff, but its press spokeswoman did confirm to BBC News NI that "none of our places will close permanently".
The trust looks after a number of historic estates across Northern Ireland including Mount Stewart and Castle Ward in County Down, Florence Court in County Fermanagh and it runs a visitors' centre at the Giant's Causeway in County Antrim.
In a statement, Ms McLachlan said: "Since lockdown measures have eased, we have reopened many of our places across Northern Ireland, where it is safe and practical to do so.
"It's clear from the response from our members and the general public that the access we provide to nature, beauty and history is so important for our health and wellbeing.
"The measures we have had to announce today will ensure that our charity can continue to fulfil this mission for the long term."
'We simply have no other choice'
In July, the National Trust warned that cuts were inevitable as the pandemic had affected almost every area of its income.
At that time, it proposed 1,200 compulsory redundancies across the UK, to save almost £60m of its annual staff budget.
On Thursday, the conservation charity announced that following a consultation with its staff, the number of compulsory redundancies had been reduced to 514.
However, a further 782 staff have agreed to take voluntary redundancy, meaning a total of 1,296 workers are now leaving the organisation.
The trust's director general Hilary McGrady, who is originally from Belfast, said: "No leader wants to be forced into announcing any redundancies, but coronavirus means we simply have no other choice if we want to give the charity a sustainable future.
"We have exhausted every other avenue to find savings, but sadly we now have to come to terms with the fact that we will lose some colleagues."
In addition to the job cuts, the charity aims to save another £41m through efficiencies, such as reducing its office and travel costs, and lowering its spend on IT and marketing.
Ms McGrady said: "In making these changes now, I am confident we will be well-placed to face the challenges ahead, protecting the places that visitors love and nature needs, and ensuring our conservation work continues long into the future."