In his introduction to Yang's Cranes of the World, Jim Harris, president of the International Crane Foundation, agreed that art is a powerful means of changing the world, and argued that Yang's paintings draw on tradition, science, and detailed personal observations and photographs to show cranes as they really are in the living world.
世界鶴類基金會主席吉姆哈里斯在《世界鶴》畫冊序文中寫道：「藝術可以成為改變現況的一項重要力量之一。楊恩生的畫取自傳統、科學，和他親身仔細的觀察及攝影記錄，呈現了生活環境裡鶴的真實面貌。」