How many letters does the top answer for “australian and southeastern asian birds with a melodious whistling call” have?

The most common answer is thickhead (9 letters).

Crossword clue: australian and southeastern asian birds with a melodious whistling call

2 answers found in Letterora's clue database (Wikidata facts, Open Trivia DB, WordNet and Webster definitions — all licensed sources).

thickhead 9 letters wn-def

Australian and southeastern Asian birds with a melodious whistling call

whistler 8 letters wn-def

Australian and southeastern Asian birds with a melodious whistling call