A vent assembly for attachment to a fluid discharge conduit of the type connected to a clothes dryer, room exhaust fan, or the like includes a mount having an opening received on the conduit and a door pivotally received by the mount. The door includes a first surface portion for covering at least a portion of the opening and a second surface portion joined to the first surface portion and extending from the door and protruding into the opening. The door is operable for displacement with respect to the opening between an open position and a closed position when engaged by a fluid flowing through the discharge conduit. The door is in the open position only after the door pivots sufficiently to move the first and second surface portions fully out of the opening, whereby birds, animals, and the like are restricted from entering the conduit.