The incident occurred as the Swiss International Air Lines plane, operating on behalf of Edelweiss Air, was taking off from the Kloten airport.
The plane’s pilot noted suspicious vibrations from one of the jet engines, the SDA news agency reported.
“We had a bird strike during takeoff,” he radioed to Zurich airport.
The pilot decided to return to the Zurich airport, a spokesman for Edelweiss Air said, confirming information reported by Radio Argovia.
However, the pilot had to circle the plane for about an hour above the plateau region of Switzerland to consume enough fuel to allow it to land, SDA reported.
The plane was not designed to vent fuel, the news agency said.
The aircraft finally landed in Zurich shortly after 4pm.
Eidelweiss Air spokesman Andreas Meier told 20 Minuten newspaper that passengers were never in any danger and that such situations were regularly practised by the crew in the flight training simulator.
The 168 passengers were transferred to other flights or put up in hotels after the plane landed.
Bird strikes of aircraft occur up to 100 times a year at the Zurich airport despite efforts made to scare them away.