Found throughout Britain, the wood mouse is Britain's most common native rodent. Wood mice are naturally shy creatures and are active mostly during the night but they do leave telltale signs if they are in your garden. During October look out for their ball-shaped nests of woven leaves and grass, often in corners of sheds or in garden shrubs. October is also a good time to look for evidence of feeding. During this time of year wood mice use old birds' nests in hedges as places to store food and to eat it in safety.

Foxes are most active at dawn and dusk so during October, as the days shorten, there are opportunities for catching a sight of them as afternoon light fades. They have just finished their late summer moult so they will be in fine condition (glossy coats and bushy tails) at this time of year. They will fatten up for the winter by eating small mammals and hedgerow fruits. Even if you don't see a fox their droppings, with a spiral twist at the pointed end, will let you know they are living in the area.

Ivy is a very important plant, especially during autumn. Ivy’s life cycle is out of step with every British plant. It flowers in the autumn and fruits in the spring. Therefore ivy provides food and shelter to insects and birds when they need them most. Its autumn flowers provide drops of nectar as a last-minute energy resource for hibernating insects. The berries are ripe in March. They are toxic but eaten on a small scale their high fat content provides a valuable early food source for birds such as woodpigeons, starling and thrush.

The holly blue butterfly relies on ivy. They lay white, dimpled, disc-shaped eggs on ivy flower stalks. The green caterpillars that hatch look like segmented slugs and feed on the buds. They are easy to find because they leave holes where they have munched the flower buds. This species spends winter as a chrysalis, hidden in the ivy foliage. The chrysalis stage is a resting period. The adults emerge in April.

An animal to look out for while pond dipping this month is the water louse. They have 14 legs, so are different from spiders (8 legs) and insects (6 legs). Water lice belong to the Crustacean family which includes lobsters and crabs. Water lice are closely related to land-dwelling wood lice, one of just a few land-based crustaceans in the world. However, water lice have a flatter body, which is an adaptation to living in water. The flat body helps the water louse to avoid being washed away by fast moving water.

October is a good month to go on a search for harvestmen. There are plenty about at this time of year. Look for them under old logs. These long-legged animals are not true spiders because they don't have venom nor silk. Their eyes are mounted on little turrets on their circular bodies. Here are three species to look out for:

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