Help Pls .... Dead patches on lawn

Hi there. My mum has these dead patches on her lawn and I was wandering if anyone knows whats causing them and how to fix them. I enclose some images. She has no pets.
Many thanks. Clifford.

 

The lawn is behind her bungalow. Its not shaded and gets alot of sun. The photo was taken only a few days ago.
Thanks.

 

Thanks John. Nice talking to you.

 

(wondering) Has your mum got a dog?

 

that's my thoughts aswell, as there are different coloured grass on the outer edges of the rings/bare patches

 

Hi there. Many thanks for all your inputs. This sure is a nice forum.
My mum does not have a dog.
I'm thinking that she may have over-watered it and cut the lawn too short which would encourage the fungi to grow. Any views? :WINK1:

 

Your mothers lawn problem is most likely as already said a fungal disease . Usually caused by the damp autumn weather , shorter daylight ,moisture sitting on the grass throuhout the day ..In most cases the lawn will recover in time ..

Dave