The answer to 'gutter pet stains' is that common causes include pets urinating or defecating in the gutters, as well as pets tracking in dirt and debris. Symptoms include discoloration, odor, and potential clogging of the gutters. Solutions can include cleaning the gutters, using enzymatic cleaners to break down organic matter, and preventing future pet access to the gutters.
For minor stains, homeowners may be able to DIY the cleaning process. However, for more extensive or difficult to remove stains, it's best to call in a professional gutter cleaning service. They have the right equipment and expertise to thoroughly clean and deodorize the gutters, as well as identify and address any underlying issues.