Warbling p. pr. & vb. n. : of Warble

Example:
What's all this about Stalin and his Warbling-barking-dog music?

Taxonomy
Warbling Vireo, Vireo gilvus, species, Birds, free encyclopedia, least concern, nest, Search, breeds, Vireo, Birds of North America, western birds, breeding grounds, IUCN Red List, Conservation status, Passeriformes, Vireonidae, Mexico.

Defination from the web:
warble, similar to that of the Painted Bunting. ... The Brown-capped Vireo (Vireo leucophrys), resident in Central America and northern South America, is sometimes considered conspecific with the Warbling Vireo. ...