As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
CREW REPORTED AFTER TAKEOFF THEY RECEIVED A HYD SYS 1 LOW QTY MSG. THE CREW DECLARED AN EMERGENCY & RETURNED TO FIELD. THE ACFT LANDED WITHOUT INCIDENT. MX SERVICED THE NR 1 HYD SYS. NO LEAKS WERE NOTED & THE ACFT WAS RETURNED TO SERVICE.