churrs

v.

颤鸣（churr的第三人称单数形式）；

Reed warblers discriminate cuckoos from sparrowhawks with graded alarm signals that attract mates and neighbours
Pattern Analysis of Acoustical Behavior in Four Species of Ground Squirrels
Laryngeal biomechanics and vocal communication in the squirrel monkey (Saimiri boliviensis).
Life Style of Coccyzus pumilus, a Tropical Cuckoo
Vocal Repertoire in the European Badger (Meles meles): Structure, Context, and Function
Drapetomanic Yes I Am
Paradise
Old School on the New
New Nature Trails
Winter behavior and ecology of the Alder Flycatcher (Empidonax alnorum) in Peru