It's a problem of perceptions of long and short-term benefit, "says Keith Highley. He argues that even though there is no precise data on shark numbers, if there are sufficient grounds for suspecting that sharks 'numbers are declining, then action should be taken without delay.
「這是個長遠與近利的觀念問題」，張敬玉說，有關鯊魚的精確數據雖是未知，但如果有證據足以讓人懷疑鯊魚的數量在減少，就應該先採取一些行動了。