It's lambing season at Norfolk Wildlife Trust reserves. Dave Tallentire, NWT Conservation Grazing Manager, tells us more.

The cold weather during late winter has certainly pushed back the arrival of spring. However, spring is now definitely here, bringing back an abundance of colour and life to our countryside.

Spring is signalled in different ways across our nature reserves - NWT Foxley Woods develops a cover of blue due to the flowering bluebells, at NWT Hickling Broad, spring brings back the booming noise of the bitterns which nest in the reed beds... while at East Wretham Heath, spring is greeted by the arrival of our new lambs.

Livestock grazing is one of the most important tools we have for managing our nature reserves. By munching their way across our nature reserves, the sheep maintain open habitats, allowing a whole range of plants, insects, birds, reptiles and mammals to flourish.

Without this regular removal of vegetation, many of our nature reserves would be at risk of being swamped by just a small handful of the more dominant plant species. Since its humble beginnings 25 years ago, our flock has been through significant changes. It began in the early 1990s when NWT acquired five Hebridean sheep on little more than a whim.

However, the flock has proven itself invaluable to the management of our nature reserves and has grown to

number more than 500. We have trialled numerous different systems and sheep breeds over the years, but now our flock currently consist of two different breeds, Shetlands and Black Welsh Mountains. Whereas most modern sheep farming has switched to more productive, commercial breeds of sheep, NWT has continued to rely on traditional native breeds.

Despite being relatively small, these are very hardy and able to thrive on the nature reserves. As well as helping us with our conservation goals, our breeding flocks also helps to secure the future of these diminishing breeds.

The hardiness of the Shetlands and the Black Welsh Mountain breeds make these sheep ideally suited to thrive on our nature reserves. All the hard work that goes into preparing the sheep for lambing and helping them through this process is well worth it. It is great to watch them skipping around on the breckland heaths knowing that these pint-sized conservationists are helping to protect these special areas for wildlife simply through their grazing.

The Shetland lambs come in a range of colours and markings, and no two ever seem to look alike! The fleeces are very soft and well crimped, making them highly valued by local spinners and craftsmen. The lambs are quickly up on their feet, often giving our shepherd the run around within hours of being born.

The area that they lamb includes lots of shelter, plenty of food, and with minimal disturbance the ewes are free to find a secluded spot to give birth. However, our shepherd is on site as much as possible to assist the odd few ewes that run into difficulty. The new mothers and their lambs are then penned into a separate paddock to encourage a close bond, it also allows the shepherd to keep a close eye on them and make sure the lambs are getting enough milk.

The lambs will spend the summer with their mothers, predominantly grazing on the Breckland heaths and in autumn the ewe lambs will enter into the main flock and ensure that this nibbling for nature continues for years to come.

NWT East Wretham Heath is the base of our sheep flock, and you can see the ewes grazing here all summer alongside their lambs. Alternatively, you can visit the nearby NWT Weeting Heath Visitor Centre, where the flock work to maintain the special flora and fauna of this National Nature Reserve.

NWT Weeting Heath NNR nature reserve and Visitor Centre with refreshments is open until July 31 from 9.30am-4.30pm, and there are Open Weekends during August. Postcode IP26 4NQ.

Call the centre on 01842 827615. NWT East Wretham Heath is open dawn till dusk, every day. Postcode IP24 1RU.