Photo Source: Discover Magazine The environmental impact of free ranging domestic cats within the Hooffs Run watershed will be addressed in the post. According to the Audubon Society of Northern Virginia (ASNV), free roaming domestic and feral cats are the second biggest driver of the decline in birds in the US and Canada. Furthermore, “free roaming cats threaten birds and other wildlife, disrupt ecosystems, and spread diseases.” The Wildlife Society notes that free roaming cats “decrease native wildlife abundance and diversity, especially of species that nest on or near the ground”, and are responsible for “at least 33 bird species globally”. Within the Hooffs Run watershed it is difficult to determine exactly which birds are at most risk from free roaming cats, but Mourning Doves, Sparrows, Northern Cardinals, Starlings and Blue Jays are likely to be at high risk given their prevalence. In 2016 the Smithsonian Magazine reported that "Americans own about 86 million cats, o