Greylag Goose

It's been such a warm and sunny afternoon (23 degrees) so I called at the lake after work and enjoyed a lovely walk after being indoors all day.
I took lots of photographs of Spindle Berries, a Heron in flight (too blurred), and the three remaining Cygnets but this little Greylag Goose, the only one amongst dozens of Canada Geese and Mallards, caught my eye. I was surprised when I downloaded the pictures to see that he appears to have 'teeth', is this to filter out the food from the water do you think. Those nostrils seem quite awesome too, but I do like his colouring, very autumnal..