The garden tiger is an attractive, brown-and-white moth of sand dunes, woodland edges, meadows and hedgerows; it will also visit gardens. In decline, it is suffering from the 'tidying up…

A plant of chalk and limestone grasslands and sand dunes, Yellow-wort has butter-yellow flowers. Its distinctive leaves sit opposite each other, but are fused together around the stem.

Bittersweet is a nightshade, so is toxic; its bright red berries may be tempting, but can cause serious illness. Found in hedgerows and gardens, it has purple flowers with yellow stamens.

The muntjac deer was introduced into the UK from China in the 20th century. It has gained a stronghold in southeast England, where it can cause damage to our woods through browsing.

The oak marble gall wasp produces brown, marble-shaped growths, or 'galls', on oak twigs. Inside the gall, the larvae of the wasp feed on the host tissues, but cause little damage.

A scarce and declining bird, the tree sparrow can be spotted on farmland and in woodlands; it is not an urban bird in the UK. It has a brown cap and black cheek-spots, unlike the similar house…

The common dandelion is a most familiar flower: counting down the 'clock', while blowing the fluffy seeds from its head, is a favourite childhood game. Dandelions are an important early…

Bloody crane's-bill has striking magenta flowers that pepper our rare limestone pavements, grasslands and sand dunes with summer colour. It is a favourite of all kinds of insects, including…

The little grebe is a fantastic diver, but to help it swim underwater, its feet are placed towards the back of its body, making it rather clumsy on land. It only really comes ashore to breed.

The gudgeon is a bottom-dwelling fish, similar to the stone loach, but with only two whisker-like barbels near its mouth. These sensory organs help it to find its prey in the sand and gravel of…