This ad in the Chronicle business section this morning caught our eye. It’s a reminder that the top-rated newscast at 6 p.m. is in Spanish. Univision’s KDTV 14 has been winning the news ratings at 6 p.m. since 2002, but the ad serves as a reminder of the size of the Spanish-speaking audience in the Bay Area. No doubt Channel 14’s ratings will be helped by the fact that NBC-owned Telemundo Channel 48 is dropping its local news as part of a company-wide cost cutting move. Channel 48’s newscasts will now come from the network with occassional packages being fed from a five-person bureau at the station in San Jose. Meanwhile, Univision’s second network, Telefutura, is crowing about the fact that it has edged Telemundo out of the No. 2 spot in terms of national ratings.