A recently released study by British veterinary charity organization, PDSA, claims that pets suffer from Seasonal Affective Disorder (SAD), a form of depression that tends to occur as days grow shorter and temperatures drop with the changing seasons. One in three of the surveyed pet owners said they see a noticeable downturn in their pet's mood during the winter months, with 50 percent saying their pets slept longer and 20 percent adding they were less active.

I don't know about your pets, but North is pretty hyper all the time. When he's not tearing around the apartment, he's sleeping... but I never paid attention to the mad dash to snoring ratio as the seasons change. What do you think – does your pet seem less energized in the winter? Share your thoughts and interpretations in comments below.