春江水暖鴨先知

春江水暖鸭先知
chūnjiāngshuǐnuǎnxiānzhī
  1. lit. the duck is the first to know if the spring water is warm (idiom)
  2. fig. an expert in the field knows which way the wind blows

CEDICT

Professionals within an industry or profession will be the first to notice a change in circumstances.

Wiktionary

蘇軾晚景之一:「桃花三兩春江水暖鴨先知。」比喻處於環境預先感受環境改變徵兆

重編國語辭典

Entry Composition