Helicopter Instructor reported hitting a kite while climbing out from an airport. Instructor landed and found kite string wrapped around tail section and the helicopter was grounded until maintenance could inspect aircraft.

Narrative

Helicopter departed ONP Runway 34 straight out to the north. Was about 4nm north at 900 ft. msl in climb to 1;500 northbound at 90 kts. IAS (destination ZZZ via the coast and Hightway east) when spotted what initial appeared to be a bird at similar altitude. Was difficult to see because terrain was slightly higher behind it so it blended into the trees in the distance. Started to take evasive maneuvers at which point determined it was in fact a kite; maybe 3 ft. wingspan. Time between seeing the kite and impact with the kite line was less than 15 seconds. It was unclear in flight if collision was made and there were no indications that anything was amiss with the helicopter but decided to land at the next available airport to inspect the helicopter as a precautionary measure. Upon landing discovered kite string wound around the tail rotor blade tight enough to want a mechanic to properly assess and remove so as to not cause any damage during removal. Due to the weekend and mechanic not available the helicopter was left at the airport and pilot and student drove to final destination.