Vines on a Violet Sky

Just had our bread, cheese and wine, sitting outside, looking at this, after a fairly hectic day. Utterly peaceful. Perfect temperature, after a too hot day. 

Our grapevines are doing a sterling job of growing and beginning to cover the patio. But something keeps biting the top off the third one, any ideas? Mike thinks it's a rat - but why would it climb up and bite off just the top each night? My guess is ants...

Gratefuls:
- violet skies and a bright moon
- creamy Manchego cheese
- deciding on a roof and ordering it in Spain - sandwiches of foam with a top that looks like the traditional red tiles they have here, but will be a heck of a lot more insulated, maintenance free, and bug proof