WATSONVILLE GAS STATION EMPLOYEES HAVE DISCOVERED ILLEGAL CREDIT-CARD-READING DEVICES INSIDE THEIR PUMPS.   THE CARD “SKIMMERS” WERE FOUND AT THE 7-ELEVEN ON FREEDOM BOULEVARD DURING ROUTINE MAINTENANCE. “SKIMMERS” ARE TOOLS USED BY IDENTITY THIEVES THAT SKIM INFORMATION FROM CREDIT AND DEBIT CARDS WHEN THEY ARE SWIPED.   OFFICIALS SAY IT IS DIFFICULT TO DETECT WHAT PUMPS CONTAIN THE DEVICE AND ENCOURAGE CUSTOMERS TO REGULARLY CHECK THEIR ACCOUNTS FOR SUSPICIOUS ACTIVITY.