The otter is such an enigmatic species. In the 1960s it wasn’t an enigma – it was just rare, driven from most of its lowland haunts by the pernicious effects of organophosphate pesticides at the top of the food chain. At the time Scotland, and in particular the Hebrides, became one of the places where the population remained at prewar levels. They were also easier to see as they were both confiding and tended to stick to very open habitats.

Following the ban on the worst of the pesticides, otter numbers have taken forty years to recover, but they can now be found in every county in the UK. Not that you would know unless you are extremely lucky – they seem to have the uncanny ability to slink away in the most unbelievable way. Their ability to hide makes me think that you only really see an otter, when the otter wants you to see it. I have had the great joy to fish with otters quite a few times – they always seem indifferent to my presence, until I cross some invisible line and they decide that is enough and they simply disappear.

An otter is also quite a large animal to just simply disappear. Forget the idea that it is just a rather large stoat, most otters are impressively big, especially the male dog otters. This was driven home to me when we were on a walk over to Roisinis, where Bonny Prince Charlie had waited patiently for Flora MacDonald to appear with his sex change disguise before she had to row him over to Skye (thankfully not on her own). Two archaeologists appeared saying that they had just seen an otter that was bigger than the border collie sized dog that they had with them. So think labrador size and you’ll have the right idea. This is the other problem with otters – people are always appearing saying did you just see the otter. Otter, where? They will point in a general direction and lo and behold another otter has pressed the hyperspace button and completely disappeared.

In North Uist, there are otters everywhere, or should I say signs of otters everywhere. Otter prints, with telltale tail mark and their lopping double paw impression are on the beaches. You can find otter roads leading off the beaches onto the machair, usually heading for a freshwater loch where they wash off the saltwater and thus restore their fur to sleak and insulating cleanliness. Otter scats, are all over the place, not just on preferred areas demarcating their territory. Otters are just everywhere. Even around the house, with a holt in the loch and a trail leading down to the tidal loch, where Kate disturbed one whilst I was away.

So I had been waiting for an otter to decide to put in an appearance. As usual for me, I needed to have a fishing rod in hand to prove I was a fisherman for the supreme fisherman to allow a view.

A short walk across the soft sand of Geirran Mill and hidden behind a small promontory is one of the largest sea pools on the island. Standing at the top willing a fish to put in appearance to raise our hopes after a rather dour season so far, a large head appeared about halfway down. So large that my immediate impression was seal – even I was lulled into a false sense of perspective. A sublime, rippleless dive was followed by the appearance of a long, thick tail – that otter is the size of a seal. Forget labrador size, readjust the scale. This otter was huge. And quite unperturbed. It looked at me the next time it surfaced and then went back to fishing. Later I was to discover that the place it was fishing was rammed with small pollack, but I like to think that it was after the tastier sea trout that would occasionally launch themselves out of the water in a just you try and catch me aerobatic display. The otter just kept surfacing and diving, occasionally looking over to see if I was going to fish or not. Finally it simply bobbed on the surface looking at me, swam towards me and out on to the beach, shook itself dry and scamped towards me, like a lithe, four footed seal. It really was a king-sized otter. It scampered behind a boulder and completely disappeared. How do they do that?