It's messy but for our wildlife it's vital. Carrie Carey of the RSPB on why mud, glorious mud is so vital for our East Anglian birds -– and our own well-being too.

I recently took the grandchildren to a local farm park and despite the enticement of tractor rides and sheep racing, they wanted to stay by the pig pen where a family of hogs were enjoying a very messy mud bath. My youngest granddaughter looked at me knowing and said 'They're really happy, aren't they?' I had to admit, it did seem that way.

Many farmers know that mud aids the animals' thermoregulation, helps with parasite removal and affords sun protection. Whatever the reason, there is no doubt that pigs like to wallow in the mucky stuff (or 'mud, glorious mud' as the old Flanders and Swann song put it).

By definition, mud is simply a mixture of earth, or soil, and water and is the building block for all things organic. On the surface, you might assume that mud is a barren and lifeless substrate, but nothing could be further from the truth; mud habitats form ecosystems that support a diverse community of wildlife.

Around Britain's coast, intertidal mudflats that occur in estuaries and harbours play host to a plethora of marine life. Brittlestars, anemones and spider crabs make their homes on the muddy seafloor, while a vast number of invertebrates and polychaete worms burrow deep into the mud itself and provide a rich diet for overwintering wildfowl and waders. At RSPB Snettisham reserve, the mudflats act as an open diner, supporting an impressive population of knot, dunlin, godwits and other migrant birds throughout the year.

However, it is not just birds that profit from the muddy seabed: our planet does too. The burrowing activities of sea critters allows the exchange of oxygen, nutrients and minerals to take place between seawater and sediment and this plays an important part in Earth's respiratory process. A high moisture content is necessary to support the needs of the plants, animals and organisms that live here. Remove the moisture and the mud reverts to soil which plays an equally vital role in maintaining life on land. Soil acts as a carbon store, filters rainwater, supports vegetation and is the producer of almost all of our antibiotics.

Soil has another positive impact on our health and wellbeing. It contains a bacterium found to trigger the release of serotonin: a group of hormones that regulate mood, social behavior and sleep. So there is good reason to get out in the garden, dig in the dirt and make mud pies! Ancient Egyptians believed that a mud bath helped relieve joint and muscle pains as well as promote relaxation and calmness.

There is also growing evidence that a tactile relationship with soil fills a basic biological need and helps us build a connection with the natural world. The Latin word for soil is 'humus' and the words human and humility come from this same root. No wonder then that we are intrinsically linked to soil, earth, dirt, mud. While we may not be inclined to spend a day wallowing in a mud pit, it is certainly evident that some times, reconnecting with nature's building block can be beneficial on so many levels. So I'm off into the garden to have a root around the compost heap and breathe in the smell of good old-fashioned dirt.