It's a sad truth but many once common animals are in trouble and desperately need help.

Over the last 50 years, two thirds of the UK’s plant and animal species have declined in numbers, with some of our much loved garden visitors, such as house sparrows, starlings and frogs becoming increasingly endangered.

The humble hedgehog highlights the plight of our garden wildlife perhaps more than most. Numbers have fallen by 30% since 2002, with the UK population now estimated to be fewer than one million. They have suffered a fate comparable to the loss of tigers globally.

The main reasons for this downward trend are thought to include over-management of parks and green spaces, loss of gardens to paving and decking, less insects to eat because of the use of pesticides, fragmentation of home ranges by fences and roads. The list could go on.

Any species would struggle with odds like these stacked against them.

But it’s not too late to make a positive change, and it only takes a few simple steps to transform your garden, school or community space into a haven for hedgehogs and other wildlife this autumn.

That’s the message for gardeners from the The Wildlife Trusts and the Royal Horticultural Society, who have joined forces with Hedgehog Street for this year’s Wild About Gardens Week, an annual celebration of garden wildlife that runs from 26 October to 1 November.

And with around 15 million gardens in the UK covering an estimated area of half a million hectares, there’s plenty of potential for these gardens, once connected, to act as little nature reserves full of slugs, snails and worms that hedgehogs and other wildlife love to eat, as well as providing comfy places to nest.

Dubbed "gardener’s best friends" because they eat lots of unwelcome species, hedgehogs just need access to lots of our green spaces to survive.

To help them, there are a few easy things that you can do that would have massive benefits, with the added bonus you’ll be helping other wildlife in the process.

One of the most effective things you can do is to cut a small CD-sized hole (13cm x 13cm) in your fence to create "hedgehog highways", because they can travel 1-2km every night, roaming across 20 hectares in search of food, mates and nesting sites. Here is a handy template to printout out and once you’ve done it, you can register the hole on the Hedgehog Street map.

A comfortable and safe house is best situated in a quiet spot against a fence or wall. A warm, dry home is essential for hedgehogs if they are to survive the winter, and it can also turn into a safe space for a female to rear her young in the spring. They don’t have to be three storey mansions, just a simple cottage will do and they don’t have to take long to build. The British Hedgehog Preservation Society have some great designs and helpful hints to get you started, while Hedgehog Street has some neat homes that people have built to give you ideas.

Fallen leaves at this time of year are perfect nesting material for hedgehogs, and gathering them into a heap makes for a simple and comfortable nesting place. Also, by leaving some leaves lying around, you will create a habitat for some of the hedgehog’s food, such as ground beetles.

A simple pile of logs or wood can also make an effective hedgehog nest. As hedgehogs need to feed intensely before hibernating for the winter, log piles can double as a great habitat to encourage a rich feast of earwigs, centipedes and woodlice. Here are five ways to use logs in the garden.

Growing a variety of plants and even letting the grass grow a bit wild in a small area of the garden will attract insects for hedgehogs to feast on. But do check before mowing or strimming in case any animals have taken residence in there.

Ponds are one of a number of varied habitats that are beneficial to lots of garden wildlife. Although hedgehogs can swim, they sometimes need a little helping hand, so some stepping stones or a plank will help all sorts of animals get in, and importantly for hedgehogs, back out of the water. The good news is ponds can only take a weekend to put in.

Reducing the use of pesticides and slug pellets will encourage back all the foods that hedgehogs need to eat to stay healthy, think of them as your natural pest controller. But above all else keep it green and avoid paving or decking over large areas where possible, it’ll benefit all wildlife and not just hedgehogs!

And remember to check for wildlife before lighting any bonfires. If you find a hedgehog and are worried then the British Hedgehog Preservation Society can offer advice.

The full details of Wild About Gardens Week are on the website including events, hints and tips on wildlife gardening and downloadable booklets. There will also be a hedgehog question and answer event on Twitter using #wildgardensQA on 28 October between 1200 and 1300 hours.

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