Common Darter (Sympetrum Striolatum) Semi-mature Female on a Bramble in Whiteley Woods
I don't know why Dragonflies perch on Brambles, although in this case it's probably inexperience, as we can tell from her colouring that this female Common Darter is a very young adult. You can see that she has already had a piece torn out of her left hindwing, probably by landing on the very same plant, as dragonflies are such creatures of habit. Unfortunately there are no second chances with this type of incident and if she continues to use this perch she could become unable to fly even before obtaining her full adult colours.