Cats' threat to wildlife in San Diego County

(from http://www.utsandiego.com)

...In San Diego County, the potential threat feral cats pose to wildlife is particularly troublesome. Our county is within one of the world’s biodiversity hot spots. Our ocean, beaches, bays, mountains and desert landscapes, and unique coastal sage scrub and chaparral plant communities, support a wide diversity of plant and animal life, including more than 500 species of birds.

San Diego County is home to more endangered species than any other county in the nation.

Many of these species exist in small islands of habitat surrounded by urban development. At the edges of these small habitat patches, urban predators — animals that thrive in developed landscapes and prey on native species — pose a significant threat to their survival. Some of the urban predators that disturb or kill sensitive bird species in our county include crows, ravens, raccoons, opossums, rats — and feral cats.

One example of this situation can be found at the Kendall-Frost Marsh in Mission Bay. The marsh is home to a population of federal- and state-listed endangered light-footed clapper rails, a secretive bird that relies on coastal wetland habitats. Urban predators are trapped in the marsh as part of management efforts to protect clapper rails. Feral cats have been trapped at the marsh and brought to San Diego County’s animal shelter. This co-occurrence of feral cats and light-footed clapper rails creates the possibility of a predation problem. Biologists who monitor this species counted fewer than 600 breeding pairs in 2013. Predation of even a few of these birds may have a significant effect on the species’ ability to recover to stable population numbers in the marsh....