There are lots of resources on the web to help you green up your pet. One, Planet Green, says to keep your cat inside, and your dog on a leash.
Says the site: “Topped only perhaps by habitat destruction, cats are the biggest, baddest bird killers of all time. Even wind turbines have got nothing on them. While you may poo-poo high cat-related bird-mortality rates as collateral damage in the great Circle of Life, domestic cats do have an unfair advantage. Unlike wild predators, house cats are always well fed, well rested and in tip-top fighting shape.” The site also points out that indoor cats live a lot longer.