Basset hounds have a tendency to look, well, unimpressed, even when they are fully content. It's the nature of the breed!
In fact, there is a fairly popular dog meme called "unimpressed bassets," which I frequently evoke on my dog blog. Explaining humor is a tad silly, but I'll do so anyway: the point of this meme is to show bassets, who look like they could not care less, in happy settings, from birthday parties full of dog treats to beautiful landscapes.
Here too, my basset appears to be thinking, "Nature...pfffft!"