What was found
MODERATE RAIN, ALL ANTI-ICE SYSTEMS ON. DURING DESCENT, RECEIVED IAS COMPARTER ALERT FOLLOWED SHORTLY BY SEL ELEV FEEL MAN AND SEL FLAP LIMIT OVRD LEVEL 2 ALERTS. ALSO RECEIVED A/P AND ATS DISCONNECTED. SUSPECT F/O PITOT STATIC FROZEN. FOLLOWED QRH FOR AIRSPEED UNRELIABLE ONCE IN WARMER TEMPERATURES. RECONNECTED THE A/P AND ATS AND ALL INDICATIONS WERE NORMAL. INSPECTED AND LEAK TESTED THE CAPTAIN`S, AUX & FIRST OFFICER`S PITOT STATIC SYSTEM IAW AMM: 34-11-00-2. FOUND DRAIN HOLES IN F/O'S PITOT TUBE PLUGGED. PURGED THE FIRST OFFICER'S PITOT SYSTEM AND CAPTURED, CONFIRMED PRESENCE OF BIOLOGICAL DEBRIS. REMOVED AND REPLACED THE FIRST OFFICER'S PITOT TUBE IAW AMM 34-11-02-2, AND OPS CHECKED GOOD, ALL PITOT STATIC CHECKS WERE GOOD. HEAT TESTED GOOD IAW AMM 34-16-00-5. ACCOMPLISHED A NR 1 & 2 FCC AFS TESTS AND ALL TESTS PASSED IAW AMM 22-00-00-2.