This hefty diving bird is a winter visitor to the UK, where it can be seen around the coast or occasionally on large inland lakes.

A low-growing plant of sand dunes, heaths and grassy places, Common centaury is in bloom over summer. Look for clusters of pretty, pink, five-petalled flowers.

A tall plant, purple-loosestrife can form dense stands of bright purple flower spikes in wet habitats like reedbeds, fens and marshes.

Traditionally a coastal species, Lesser sea-spurrey has spread inland, taking advantage of the winter-salting of our roads. Its pink-and-white flowers bloom in summer.