Supervisor Ron Roberts represents the Fourth Supervisorial District, considered the most ethnically diverse district in San Diego County. Approximately 630,000 people reside in the district, which encompasses a majority of the City of San Diego. Since his election to the Board of Supervisors in 1994, Supervisor Roberts has focused his energy on a wide variety of issues, from improving the plight of foster youth, assisting vulnerable seniors and enhancing public safety, to supporting growing the regional economy and making sure that the County of San Diego remains one of the best-managed counties in America. Because all of the Fourth Supervisorial District is located within the City of San Diego, the bulk of municipal services, like street improvements, trash collection and tree trimming, fall under the jurisdiction of the San Diego City Council. In general, the Board of Supervisors is responsible for issues that are more regional in nature, such as public health, animal control, air quality, water quality, probation and operation of the jail system. The Fourth Supervisorial District spans 100 square miles, extending north to UC San Diego, west to the Pacific Ocean, east to Encanto and south to Paradise Hills. The district also includes the neighborhoods of Adams North, Alta Vista, Bay Ho, Bay Park, Birdland, Castle, Cherokee Point, Chollas Creek, City Heights (where more than 30 languages are spoken), Clairemont Mesa, Colina Del Sol, Corridor, Cortez, Crown Point, El Cerrito, Emerald Hills, Encanto, Fairmount Park, Fairmount Village, Golden Hill, Hillcrest, Jamacha Lomita, Kearny Mesa, Kensington, La Jolla, Linda Vista, Little Italy, Loma Portal, Middletown, Midway, Mission Beach, Mission Hills, Mission Valley, Morena, Normal Heights, North Park, Oak Park, Ocean Beach, Pacific Beach, Park West, Redwood Village, Serra Mesa, Skyline, South Park, Swan Canyon, Talmadge Park, University Heights, Valencia Park, Webster and northeastern downtown San Diego. Points of interest within the district include Old Town State Historic Park, Balboa Park and the world-famous San Diego Zoo.