Did you know that you can listen to many of your favourite podcasts first on BBC Sounds?

Like Desert Island Discs, where you can hear castaways like Cher, Gareth Southgate and Nick Cave,

and enjoy longer versions of the music they've picked. Good things come to those who don't wait.

Listen to your favourite podcasts first on BBC Sounds.

This Scotland Outdoors podcast from BBC Radio Scotland.

Hello and thank you very much for choosing to listen to this. I'm Mark Stephen. In this week's podcast, I'm in the very south of Scotland at the Calaverick Wetland Centre.

It was run by the Wildfell and Wetland Trust.

It's a big nature reserve. It's about 1,500 acres and it sits on the Sawway Firth.

Now the Salt Way Firth is... It's big skies country, really.

It's a very unusual, rather beautiful quality of light,

and the big skies are very often full of birds,

particularly geese.

It's what Kalaverick is really known for.

But that wasn't why I went to visit it on this occasion.

I wanted to explore a particular form of habitat, salt marshes.

My guide for the trip is David Pickett, whose site manager at Calaverick.

Okay, so what I thought we could do is if we could walk down to the salt cut hide,

which is right on the edge of the salt marsh, and then we could go off-piece to bit and go out onto the edge of the salt marsh

and just get a feel for what Calaverroch's all about.

What does Calaverick actually mean?

Well, it means Castle of the Skylark.

So Lavaroch is a Scots name for Skylark,

...