Roof felt partially ripped by squirrels

[tellme_why]

Hi,
Sixities house roof has a dark green layer of felt (? not even sure what's its name..) - it's quite sturdy.
I noticed it's ripped in one place and I can see light coming in from a gap in the roof tiles.
No sign of water coming in.
I am pretty sure a squirrel did the job; I have cut a tree the little bugger used to climb to the roof so not coming back, but it left the nasty gift anyway.
Anyone knows how can I repair this?
Picture attached.
Many thanks!

 

[Alastairreid]

You have type 1f tar felt.
Butyl tape would be your best bet.
I would clear the insulation from the eaves to allow for airflow.

 

[tellme_why]

You have type 1f tar felt.
Butyl tape would be your best bet.
I would clear the insulation from the eaves to allow for airflow.

many thanks,
I just found out that one batten is rotten and the tile is precariously hanging on.
How can I fix this without re-roofing the lot?

 

[Alastairreid]

Any repairs like that would need to be done from the roof..stripping out a few tiles and replacing any rotten felt and battens.
Simple enough job to a roofer.