A few days ago we went to the RSPB reserve of Ynys Hir, not many miles as the Raven flies, but a trip over the Cambrian Mountains to a different habitat, and to what can be a quite different climate. This time the visit was a bit disappointing, though we probably should not have expected much more for January, especially on a dull grey day with snow still in hollows beside the mountain road. Goldeneye and Slavonian grebes on the river were the highlights, though all at the limits of telescope range, and hard to make out in the dull light.
A previous visit in November 2016 was much more successful, with even an apparently wild Red-breasted goose amongst the Barnacle geese, all of which had moved on in January. However what intrigued us most in November was the behaviour of the Teal (Anas crecca) in front of the Ynys-feurig hide. They were apparently feeding amongst the vegetation beside the scrape in front of the hide, but after only a minute or so running down to the water and frantically dipping their beaks, then going back into the vegetation, feeding for a short while, then running back to the water again, repeating the process continually. Eventually we realised they were feeding amongst the dead, seed-laden, plants of Water-pepper (Persicaria hydropiper). The leaves of Water-pepper are, as the name suggests, hot, even burning-hot to taste, similar to raw chilli, but are the seeds also hot? A bit of research suggests they probably are, but I have not found any since to try out.
If they are it would be, I assume, like with the leaves, an adaption to avoid being eaten. So were the Teal eating the seeds because there was nothing else, or through choice? Like a desire for ever hotter curries, can ducks get addicted to the burning taste, and take the dash to the water when it gets too much as part of the experience?