The dazzling silver-studded blue is a rare butterfly of heathland habitats, mainly in southern England. It has undergone severe population declines in recent years.

The linnet can be seen on farmland and heathland across the UK. But, like so many other farmland birds, linnets are declining rapidly, mainly due to agricultural intensification.

The sessile oak is so-called because its acorns are not held on stalks like those of the familiar English oak. It can be found in woodlands mainly in the north and west of the UK.

The coal tit is mainly found in coniferous woodland, but can also be spotted in gardens and parks. It is smaller than the great tit, but has a similar bicycle pump-like song.

The adder's-tongue fern is so-named because the tall stalk that bears its spores is thought to resemble a snake's tongue. An indicator of ancient meadows, it can be found mainly in…

As its name suggests, the common crossbill has a large bill that is crossed at the tip - perfect for picking the seeds out of pine cones. Look for it in conifer woodlands, mainly in the north and…