After discovering that in fact Coillte now owns the lands in Sralagagh, I wrote to them instead

Dear sir/madam,
I am writing to you in connection with lands owned by Coillte in Sralagagh, Ballycastle, Co. Mayo (folio 647f -the former of estate of John Mennis). Much of this land is under forestry, but there is also an area that is subject to turbary rights which are owned by many people in the locality. The roads in and out of this area are relatively busy for bogland -with turfcutting in the summer, heavy machinery passing up and down and also local tourists using the area for the "Sralagagh loop walk" and also deer spotting.

Unfortunately, one of the bridges into the bog has become dangerous. Despite some well meaning repair attempts by locals, the situation has not improved and the bridge is slowly crumbling. Please see pictures attached. This bridge has been dangerous for some time, and has gotten worse over the winter. I believe it is only a matter of time before there is a serious accident at this bridge and a vehicle will topple into a big gulley (possibly with a heavy cargo on board) creating a serious danger to human life. At the very least there is a risk to the property of visitors.

As the landowner in this location, and conscious of the Occupier's liability acts, and furthermore conscious that previous spontaneous repairs (in this location and elsewhere on the bogs) by locals have been counterproductive at times -I ask you to move quickly to repair this bridge. The rest of the roads on this land would also benefit from a general upgrade (and indeed they are relatively short and would be inexpensive to improve) -however, this spot is an urgent risk to human life and turfcutter's property, and regardless of whether the rest of the road is improved it is vital that this bridge is repaired ASAP..

I attach a map to identify the location of the bridge I speak of.