THE wild geese are back, and one evening last week at Cambus, as the sun began to settle below the western horizon, I watched hordes of greylag and pink-footed geese swoop low over the inner Forth as they descended to their roosting sites on the far bank.

The rhythmic calls of the geese were captivating: the sound of the sub-Arctic. Watching these dusk and dawn flights of geese on the move to and from their roosts is one of nature's special experiences.

It is a cacophony of noise that is part of autumn's being, so spellbinding that one could never tire of listening to their calls sweeping across the wildness of the estuary.

There were other sounds around in this Cambus gloaming, including the soft warbling of a robin perched in a nearby hawthorn.

The tune was more melancholy in manner compared to the brashness of the spring song, and had a subtle beauty tinged with sadness, like a lament to the passing of summer.

Robins are one of the few birds that will sing all year round, and they do so because they are highly territorial, and will maintain a winter territory to keep out intruders that might compete for food.

As I listened to the robin's sweet music, an exhalation of air from the river beside me brought my head spinning round in the other direction.

It was a grey seal, rolling lazily on the surface of the water by the mouth of the Devon estuary.

The tide was sweeping in, and in with the current come salmon, entering the Devon to spawn in its higher reaches.

For the seal, this is a time of plenty, and the salmon provide an easy-to-catch and nutritious source of food.

I walked back down the track towards Cambus and on the top of the weir perched a heron. Interestingly, the heron dangled its right leg down the falls.

I might be wrong, but it looked as if the heron was using the toes on its right foot as a means of detecting any fish ascending the falls.

If this was the heron's ploy, then it is an amazing example of nature's ability to evolve and innovate in the ever-constant battle for survival.