Butterfly/moth

Butterfly/moth

Observation - Butterfly/moth - UK and Ireland. Description: Saw this on the grassy path at Slimbridge Wetland Centre along near the sea wall. I have no idea what it is but would like to. Thank you for any help.

Saw this on the grassy path at Slimbridge Wetland Centre along near the sea wall. I have no idea what it is but would like to. Thank you for any help.